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SDLRC - Scientific Articles all years by Author - Mar-Mh


The Sheahan Diamond Literature Reference Compilation
The Sheahan Diamond Literature Reference Compilation is compiled by Patricia Sheahan who publishes on a monthly basis a list of new scientific articles related to diamonds as well as media coverage and corporate announcementscalled the Sheahan Diamond Literature Service that is distributed as a free pdf to a list of followers. Pat has kindly agreed to allow her work to be made available as an online digital resource at Kaiser Research Online so that a broader community interested in diamonds and related geology can benefit. The references are for personal use information purposes only; when available a link is provided to an online location where the full article can be accessed or purchased directly. Reproduction of this compilation in part or in whole without permission from the Sheahan Diamond Literature Service is strictly prohibited. Return to Diamond Resource Center
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
Sheahan Diamond Literature Reference Compilation - Media/Corporate References by Name for all years
A B C D-Diam Diamonds Diamr+ E F G H I J K L M N O P Q R S T U V W X Y Z
Tips for Users
Posted/Published Reference CodesThe SDLRC provides 3 types of references identified in the reference code. DS for scientific article, DM for a media article, and DC for a corporate announcement. Consider DS0512-0001. The DS stands for "diamond scientific". 05 stands for 2005, the year the reference was posted. 12 represents the month the reference was posted. For all years prior to 2015 the default month is 12. -0001 is the reference's identifier and it does not mean anything. The number below the refence code, ie 2015, is the year the article was published. Note that the posted year may sometimes be later than the published year.
Sort OrderReferences are sorted by the "author" name and when the reference was posted to the compilation.
Most RecentIf the reference code is highlighted yellow, the reference was made available through the most recent monthly compilation of new literature. Use this to check out new references. When new references are posted, we make it our priority to track down an online link and obtain an abstract. With regard to older references, tracking down an abstract and an online link is a work in progress.
Link to external location of article: If the title has a link, it means we have found a location online where you can either retrieve the full article free, or purchase access to it. The Sheahan Diamond Literature Service is not a technical article procurement service; if you want a restricted article, you must deal directly with the vendor who controls the copyright to the article.
Searching this page for a specific term or authorIn your Firefox browser click Edit in the menu bar and then Find. In the Find box that shows up at the bottom of the web page enter your search term. Firefox will highlight all occurrences. This is particularly helpful when the author you are seeking was not the lead author by whom the compilation is sorted.
Sending or sharing a referenceThe left column (Posted/Published) has an embedded hyperlink for each reference. In Firefox, if you right click on it, you can obtain the link url for that reference's location within the page, which you can copy and paste into an email or any other document. You can also use the "share this link" option to tweet, facebook etc the link.
Author Index
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years - Mar-Mc
Posted/
Published
AuthorTitleSourceRegionKeywords
DS201012-0574
2010
Maraeschal, J-C.Perry, C., Rosieanu, C., Maraeschal, J-C., Jaupart, C.Thermal regime of the lithosphere in the Canadian shield.Canadian Journal of Earth Sciences, Vol. 47, 4, pp. 389-408.Canada, Northwest TerritoriesGeothermometry
DS201312-0573
2013
Maragoni, Y.R.Maragoni, Y.R., Mantovani, M.S.M.Geophysical signatures of the alkaline intrusions bordering on the Parana Bain.Journal of South American Earth Sciences, Vol. 41, pp. 83-98.South America, BrazilGeophysics - alkaline
DS1994-1100
1994
Marahushev, A.A.Marahushev, A.A., et al.Polyfacial characteristics of the Diamondiferous rocks in kimberlite and lamproite pipes.(Russian)Doklady Academy of Sciences Nauk., (Russian), Vol. 337, No. 4, August pp. 490-493.RussiaPetrology, Kimberlite, lamproite
DS1960-0862
1967
Marais, D.Marais, D.The Diamond Industry in South Africa Will Virtually Come Toa Standstill in 20 Years Unless New Sources of Diamonds Are found Soon.Mining And Minerals, FEBRUARY.South AfricaProspecting
DS1985-0411
1985
Marais, J.Marais, J.Namaqualand; Where It All Began 300 Years AgoSth. Afr. Mining, Coal, Gold and Base Metals, October pp. 33-39South AfricaHistory
DS1990-1294
1990
Marais, M.G.Salter, J.D., Downing, B.J., Rix, G.M., Marais, M.G.Development of rock pass level monitors for Finsch diamond mine, SouthAfrica14th. Cmmi Congress Held Edinburgh, Scotland July 2-6, 1990 Institute Of Mining And Metallurgy (imm) Proceedings, pp. 107-111South AfricaMining, Finsch mine
DS1995-1159
1995
Marajushev, A.A.Marajushev, A.A.Geological position, geochemistry and thermodynamics of diamondiferousimpactogenesis.Moscow University Geology Bulletin, Vol. 30, No. 1, pp. 1-19.RussiaGeochemistry, Meteorites, craters
DS1996-0882
1996
Marajushev, A.A.Marajushev, A.A., et al.The origin of diamonds in meteoritesDoklady Academy of Sciences, Vol. 344 No. 7, August pp. 165-171.GlobalMeteorites, Diamond genesis
DS1981-0281
1981
Marakushev, A.A.Marakushev, A.A.The Problem of Fluid Regime in the Formation of Diamondifero united States Rocks.Geol. Rudn. Mestorezhd., Vol. 23, No. 4, PP. 3-17.RussiaDiamond, Genesis
DS1982-0392
1982
Marakushev, A.A.Marakushev, A.A.The Diamond Bearing Igneous Rocks of Kimberlite PipesDoklady Academy of Sciences ACAD. NAUK USSR, EARTH SCI. SECTION., Vol. 256, No. 1-6, PP. 91-94.RussiaGenesis
DS1982-0393
1982
Marakushev, A.A.Marakushev, A.A.The Volcanic Nature of the Diamond Bearing Rocks of Kimberlite Pipes.Soviet Geology and GEOPHYSICS, Vol. 23, No. 8, PP. 13-23.RussiaKimberlite Genesis
DS1982-0394
1982
Marakushev, A.A.Marakushev, A.A.Problems of Genesis of Rocks With Plagioclase and DiamondsMineral. Zhurnal, Vol. 4, No. 4, PP. 14-22.RussiaBlank
DS1982-0395
1982
Marakushev, A.A.Marakushev, A.A.The Fluid Regime in the Formation of Diamond Containing RockInternational Geology Review, Vol. 24, No. 11, PP. 1241-1252.Russia, YakutiaMir, Mineral Inclusions, Mineralogy, Petrography, Diamond, Pyroxene
DS1983-0432
1983
Marakushev, A.A.Marakushev, A.A., Garanin, V.K., Kudryavtseva, G.P.The Mineralogy and Petrology of Kimberlite Pipes and Diamond Bearing Rocks.Annales Scientifiques De L' Universite De Clermont-ferrand Ii, No. 74, PP. 47-54.RussiaPetrography, Genesis, Magma
DS1984-0477
1984
Marakushev, A.A.Marakushev, A.A.Peridotite nodules in kimberlites and basalts as indicators for lithosphere deep seated structureIn: Proceedings of the 27th. International Geological Congress held Moscow, August, Vol. 9, Petrology pp. 327-342RussiaTectonics, Mantle
DS1984-0478
1984
Marakushev, A.A.Marakushev, A.A.The Petrography of Plutonic Inclusions in Kimberlites and BasaltsIzvest. Vyssh. Uchebn. Zaved. Geol. I. Razv., No. 1, PP. 37-54.RussiaBlank
DS1984-0479
1984
Marakushev, A.A.Marakushev, A.A.The Petrography of Deep Seated Nodules in Kimberltes and Basalts.International Geology Review, Vol. 26, No. 6, JUNE PP. 635-650.RussiaBlank
DS1984-0480
1984
Marakushev, A.A.Marakushev, A.A., Bezmen, N.I., Skufin, P.K., Smolkin, V.F.Layered Nickel Bearing Intrusions and Volcanic Series of Pechenga.(russian)Ocherki Fiz. Khim. Petrol., (Russian), Vol. 1, pp. 39-63RussiaBlank
DS1985-0412
1985
Marakushev, A.A.Marakushev, A.A.Mineral associations of diamond and the formation of diamondbearingmagmas.(Russian)Ocherki. Fiz. Khim. Petrol., (Russian), Vol. 13, pp. 5-53RussiaBlank
DS1986-0523
1986
Marakushev, A.A.Marakushev, A.A.Mineral associations of diamond and the problem of the formation of diamond containing magmas. (Russian)Ocherki Fiz. Khim. Petrol. Moskva, (Russian), Vol. 13, pp. 50-53RussiaDiamond morphology
DS1987-0235
1987
Marakushev, A.A.Garanin, V.K., Kudrryavtseva, G.P., Marakushev, A.A., CherenkovaA new variety of deep seated high alumin a rock in kimberlite pipesInternational Geology Review, Vol. 29, No. 11, November pp. 1366-1376RussiaFerroalkremite, analyses, Anabar region
DS1991-1048
1991
Marakushev, A.A.Marakushev, A.A., Yemelyanenko, Ye.P., et al.Formation of the concentrically zoned structure of the Konderalkalic-ultrabasic plutonDoklady Academy of Science USSR, Earth Science Section, Vol. 311, Nove. 1-6, pp. 69-72RussiaAlkaline rocks, Konder
DS1993-0970
1993
Marakushev, A.A.Marakushev, A.A.Geodynamic regions of diamond formation.(Russian)Bulletin. Mosk. Obschestva Ispyt. Prirody Otdel Geol.(Russian), Vol. 68, 2, pp. 3-18.Russia, YakutiaTectonics
DS1995-1160
1995
Marakushev, A.A.Marakushev, A.A., Mitreiki, O.B., et al.Origin of diamonds in meteorites. (Russian)Doklady Academy of Sciences Nauk. (Russian), Vol. 341, No. 3, March pp. 106-109.RussiaMeteorites
DS1995-1161
1995
Marakushev, A.A.Marakushev, A.A., Mitreikina, O.B., Zinolieva, GranovskyDiamondiferous meteorites and their genesisPetrology, Vol. 3, No. 5, Sept-Oct. pp. 407-423.RussiaMeteorites
DS1995-1162
1995
Marakushev, A.A.Marakushev, A.A., Pertsev, N.N., Zotov, I.A., Paneyakh, N.Some petrological aspects of diamond genesisGeology of Ore Deposits, Vol. 37, No. 2, March-April pp. 88-102.RussiaDiamond genesis, lamproite, Petrology
DS1995-1163
1995
Marakushev, A.A.Marakushev, A.A., Pertsev, N.N., Zotov, I.A., Paneyakh, N.A.Petrology of Diamondiferous magmatismProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 350-351.MantleMagmatism, Metamorphic complexes
DS1996-0883
1996
Marakushev, A.A.Marakushev, A.A., et al.Polyfacies nature of diamond bearing rocks from kimberlite and lamproitepipes.Doklady Academy of Sciences, Vol. 339A, No. 9, Feb., pp. 64-69.RussiaPeridotites, eclogites, Magma
DS1996-0884
1996
Marakushev, A.A.Marakushev, A.A., Pertsev, N.N., Zotov, I.A., PaneyakhSome petrological aspects of genesis of diamondInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 400.RussiaPetrology, Diamond genesis
DS1997-0729
1997
Marakushev, A.A.Marakushev, A.A.Ore bearing potential of impact ring structureGeology of Ore Deposits, Vol. 38, No. 6, pp. 442-453.RussiaImpact structure, Puchezh-Katun, Popigai, Diamond
DS1998-0937
1998
Marakushev, A.A.Marakushev, A.A., Bobrov, A.V.Specific features of crystallization of eclogite magmas at the diamond facies depths.Doklady Academy of Sciences, ol. 358, No. 1, pp. 142-5.RussiaEclogite, Crystallography
DS1998-0938
1998
Marakushev, A.A.Marakushev, A.A., Bobrov, A.V.Crystallization of eclogite and pyroxenite magmas in diamond depth facies:evidence from garnet-clinopyrox.7th International Kimberlite Conference Abstract, pp. 546-8.Russia, YakutiaDiamond inclusions, Deposit - Udachnaya
DS1998-0939
1998
Marakushev, A.A.Marakushev, A.A., Paneyakh, N.A., Rusinov, PertsovPetrological model of giant ore depositsGeology of Ore Deposits, Vol. 40, No. 3, May-June pp. 211-227RussiaMetallogeny, Petrology
DS1998-0940
1998
Marakushev, A.A.Marakushev, A.A., Suk, N.I.Carbonate silicate magmatic immiscibility and carbonatite genesisDoklady Academy of Sciences, Vol. 361, No. 5, pp. 696-99.GlobalCarbonatite - genesis
DS2001-0731
2001
Marakushev, A.A.Marakushev, A.A., Shakhotko, L.I.Formation stages and nature of the Popigai Diamondiferous ring structureDoklady Academy of Sciences, Vol. 3771, March/April pp. 274-77.RussiaTectonics - structure, Deposit - Popigai
DS200512-0685
2003
Marakushev, A.A.Marakushev, A.A., Lonkan, S., Bobrov, A.V., Hengweng, Z., Fu, L.Evolution of the SuLu eclogite ultramafic foldbelt in East China.Moscow University Geology Bulletin, Vol. 58, 6, pp. 33-46.ChinaUHP
DS200612-0864
2005
Marakushev, A.A.Marakushev, A.A., Bobrov, A.V.Problems of primary magma and the depths of Diamondiferous magmatism.Doklady Earth Sciences, Vol. 403A, 6, pp. 901-904.MantleMagmatism
DS201606-1086
2016
Maram, P.S.Feng, D., Maram, P.S., Mielewczyk-Gryn, A., Navotsky, A.Thermochemistry of rare earth perovskites Na3xRE.067-xTiO3 ( Re=La, Ce)American Mineralogist, Vol. 101, 5, pp. 1125-1128.TechnologyPerovskite
DS201112-0269
2010
Maran, N.Dinesh, A.C., Maran, N., Shareef, N.M., Chandrasekaraiah, K.C., Jayaprakash, C.Observations on the reported incidence of micro-diamonds in the beach sands of the Kanyakumari Coast, Tamil Nadu.Journal of the Geological Society of India, Vol. 76, 6, pp. 587-588.IndiaAlluvials
DS201112-0270
2010
Maran, N.Dinesh, A.C., Maran, N., Shareef, N.M., Chandrasekaraih, K.C., Jayaprakash, C.Observations on the reported incidence of micro-diamonds in the beach sands of the Kanyakumari coast, Tamil Nadu.Journal of the Geological Society of India, Vol. 76, pp. 587-588.India, Tamil NaduMicrodiamonds
DS201212-0442
2012
Marangoni, Y.R.Marangoni, Y.R., Mantovani, M.S.M.Geophysical signatures of the alkaline intrusions bordering the Parana Basin.Journal of South American Earth Sciences, in press available, 48p.South America, Paraguay, BrazilGeophysics - magnetics
DS200412-2012
2003
Marani, M.P.Trua, T., Serri, G., Marani, M.P.Lateral flow of African mantle below the nearby Tyrrhenian plate: geochemical evidence.Terra Nova, Vol. 15, 6, pp. 433-440.AfricaGeochemistry
DS200412-1223
2004
Maraschal, J.C.Maraschal, J.C., Nyblade, A., Perry, H.K.C., Jaupart, C., Bienfait, G.Heat flow and deep lithospheric thermal structure at Lac de Gras Slave Province, Canada.Geophysical Research Letters, Vol. 31, 12, June 28, 10.1029/2004 GLO20133Canada, Northwest TerritoriesGeothermometry
DS200412-0071
2004
Maraschal, J-C.Audet, P., Maraschal, J-C.Variations in elastic thickness in the Canadian Shield.Earth and Planetary Science Letters, Vol. 226, 1-2, Sept. 30, pp.17-31.Canada, Saskatchewan, Manitoba, OntarioGravity, isostasy. Hudson Bay, Williston Basin
DS1992-0993
1992
Maraschal, M.Maraschal, M., Fyfe, W.S., Percival, J., Chan, T.Grain-boundary graphite in Kapuskasing gneisses and implications for lower-crustal conductivityNature, Vol. 357, No. 6380, June 25, pp. 674-676OntarioGeophysics, Kapuskasing uplift
DS1986-0524
1986
Maraukshev, A.A.Maraukshev, A.A., Taskaev, V.I.Composition variations in minerals from garnetiferous peridotites and eclogites and their genetic significance.(Russian)Izv. Vyssh. Uchebn. Zaved. Geol. Razved., (Russian), No. 5, pp. 9-41RussiaEclogite
DS1989-0931
1989
Maravic, H.v.Maravic, H.v., Mortenai, G., Roethe, G.The cancrinite-syenite/carbonatite complex of Lueshe,Kivu/northeast Zaire:petrographic and geochemical studies and its economic significanceJournal of African Earth Sciences, Vol. 9, No. 2, pp. 341-355Democratic Republic of CongoCarbonatite, Geochemistry, petrography
DS1997-0631
1997
Maravic, H.V.Kramm, U., Maravic, H.V., Morteani, G.Neodynium and Strontium isotopic constraints on the petrogenetic relationships between carbonatites...Journal of African Earth Sciences, Vol. 25, No. 1, July pp. 55-76.Democratic Republic of CongoCarbonatite, Cancrinite syenites, Lueshe alkaline complex
DS201012-0460
2010
Marazzo, M.Lustrino, M., Marazzo, M., Melluso, L., Tassinari, C.C.G., Brotzu, P., Gomes, C.B., Morbidelli, RubertiPetrogenesis of early Cretaceous silicic volcanism in se Uruguay: the role of mantle and crustal sources.Geochemical Journal, Vol. 44, 1, pp. 1-22.South America, UruguayRhyolites - not specific diamonds - backgrounder
DS1989-0932
1989
Marbeau, J-P.Marbeau, J-P.The importance of modeling. the microcomputer can now model deposits sowell that it has become a basic tool of explorationEngineering and Mining Journal, Vol. 190, No. 11, November pp. 22-25GlobalComputer, Deposit modeling -overview
DS1999-0443
1999
Marcano, M.C.Marcano, M.C., Van Der Voo, R., MacNiocaill C.True polar wander during the Permo-TriassicJournal of Geodynamics, Vol. 28, No. 2-3, Sept. 2, pp. 75-95.MantleGeophysics - thermodynamics, Lithosphere
DS1990-0365
1990
Marcantonio, F.Corriveau, L., Heaman, L.M., Marcantonio, F., Vanbreemen, O.1.1 GA potassium-rich alkaline plutonism in the southwest Grenville province-Contributions to Mineralogy and Petrology, Vol. 105, No. 4, pp. 473-485OntarioAlkaline rocks, Geochronology
DS202012-2206
2020
Marcelli, M.Borisova, A.Y., Bindeman, I.N., Toplis, M.J., Zagrtdenov, N.R., Guignard, J., Safonov, O.G., Bychkov, A.Y., Shcheka, S., Melnik, O.E., Marcelli, M., Fehrenbach, J.Zircon survival in shallow asthenosphere and deep lithosphere.American Mineralogist, Vol. 105, pp. 1662-1671. pdfMantlemelting

Abstract: Zircon is the most frequently used mineral for dating terrestrial and extraterrestrial rocks. However, the system of zircon in mafic/ultramafic melts has been rarely explored experimentally and most existing models based on the felsic, intermediate and/or synthetic systems are probably not applicable for prediction of zircon survival in terrestrial shallow asthenosphere. In order to determine the zircon stability in such natural systems, we have performed high-temperature experiments of zircon dissolution in natural mid-ocean ridge basaltic and synthetic haplobasaltic melts coupled with in situ electron probe microanalyses of the experimental products at high current. Taking into account the secondary fluorescence effect in zircon glass pairs during electron microprobe analysis, we have calculated zirconium diffusion coefficient necessary to predict zircon survival in asthenospheric melts of tholeiitic basalt composition. The data imply that typical 100 micron zircons dissolve rapidly (in 10 hours) and congruently upon the reaction with basaltic melt at mantle pressures. We observed incongruent (to crystal ZrO2 and SiO2 in melt) dissolution of zircon in natural mid-ocean ridge basaltic melt at low pressures and in haplobasaltic melt at elevated pressure. Our experimental data raise questions about the origin of zircons in mafic and ultramafic rocks, in particular, in shallow oceanic asthenosphere and deep lithosphere, as well as the meaning of the zircon-based ages estimated from the composition of these minerals. Large size zircon megacrysts in kimberlites, peridotites, alkali basalts and other magmas suggest the fast transport and short interaction between zircon and melt.The origin of zircon megacrysts is likely related to metasomatic addition of Zr into mantle as any mantle melting episode should obliterate them.
DS201711-2510
2017
MarceloAssumpcao, P.M.Farrapo Albuquerque, D., SandFranca Lucas, G., MarceloAssumpcao, P.M., Lucas, M.B., CondoriQuispe, C., Oliveira, M.E.Crustal structure of the Amazonian craton and adjacent provinces in Brazil.Journal of South American Earth Sciences, Vol. 79, pp. 431-442.South America, Brazilcraton

Abstract: The study of the crust using receiver functions can provide valuable geological information, such as average crustal composition, its formation dynamics and the tectonic evolution of a region, as well as serve as an initial reference for the generation of seismic wave velocity models to improve earthquake location. To fill in gaps in information on the crust of the Amazonian Craton and adjacent provinces in Brazil, we used receiver functions and H-k stacking to estimate crustal thicknesses and the VP/VS ratios. The results indicate that the crust of the study region is predominantly felsic, with an average VP/VS around 1.73 and an average thickness of 38.2 km, with a range of 27.4-48.6 km. Minimum curvature interpolation of the crustal thickness values has made it possible to delimitate of the Amazonian Craton, which corresponds to the area with an average thickness equal to or greater than 39 km. In addition, it was possible to identify its potential cratonic blocks, as well as the Paranapanema Block of Paraná Basin. The geometry of the craton, defined by its crustal thickness, is corroborated by the distribution of natural seismicity that accompanies its edges. These are related to suture zones between the Amazonian, São Francisco/Congo and Paranapanema paleocontinents. The sedimentary basins that have undergone rifting processes have a thinner crust, usually less than 37 km thick. Due to the great variability of the results, it was not possible to determine a characteristic value of c
DS1989-0933
1989
Marcelot, G.Marcelot, G., Dupuy, C., Dostal, J., Rancan, J.P., Pouclet, A.Geochemistry of mafic volcanic rocks from the Lake Kivu (Zaire and Rwanda)section of the western branch Of the African riftJournal of Volcanology and Geothermal Research, Vol. 39, No. 1, October pp. 73-88Democratic Republic of CongoTectonics, Rifting
DS202003-0354
2020
March, S.O'Neill, C., March, S., Bottke, W., Fu, R.The role of impacts in Archean tectonics.Geology, Vol. 48, pp. 174-178.Australia, Africa, South Africacraton

Abstract: Field evidence from the Pilbara craton (Australia) and Kaapvaal craton (South Africa) indicate that modern tectonic processes may have been operating at ca. 3.2 Ga, a time also associated with a high density of preserved Archaean impact indicators. Recent work has suggested a causative association between large impacts and tectonic processes for the Hadean. However, impact flux estimates and spherule bed characteristics suggest impactor diameters of <100 km at ca. 3.5 Ga, and it is unclear whether such impacts could perturb the global tectonic system. In this work, we develop numerical simulations of global tectonism with impacting effects, and simulate the evolution of these models throughout the Archaean for given impact fluxes. We demonstrate that moderate-size (?70 km diameter) impactors are capable of initiating short-lived subduction, and that the system response is sensitive to impactor size, proximity to other impacts, and also lithospheric thickness gradients. Large lithospheric thickness gradients may have first appeared at ca. 3.5-3.2 Ga as cratonic roots, and we postulate an association between Earth’s thermal maturation, cratonic root stability, and the onset of widespread sporadic tectonism driven by the impact flux at this time.
DS200412-0331
2004
Marchand, J.Ciesielski, A., Marchand, J., Vaillancourt, C.Volcanic hosted diamonds from northern Ontario: a non-kimberlitic origin.Geological Association of Canada Abstract Volume, May 12-14, SS14P02, p. 274.abstractCanada, OntarioVolcaniclastic breccias
DS1960-1110
1969
Marchand, M.Gold, D.P., Marchand, M.The Diatreme Breccia Pipes and Dykes and the Related Alnoite,kimberlite and Carbonatite Intrusions Occur in the Montreal Area and Oka Areas, Quebec.Geological Association of Canada (GAC)-Mineralogical Association of Canada (MAC) GUIDEBOOK, GEOLOGY of THE MONTREGIAN HILLS, PP. 5-42.Canada, QuebecRelated Rocks
DS1970-0130
1970
Marchand, M.Marchand, M.Ultramafic Nodules from Ile Bizard, QuebecMsc. Thesis, Mcgill University, 73P.Canada, QuebecAlnoite, Kimberlite
DS1993-0971
1993
Marchand, M.Marchand, M.Diamond exploration in the Peace River Arch, AlbertaThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) , Annual Meeting Abstracts approximately 10 lines, Vol. 86, No. 968, March POSTER ABSTRACT p. 68.AlbertaCraton, Tectonics
DS1995-1164
1995
Marchand, M.Marchand, M.Metallic and industrial mineral assessment report on the Horseshoe Peace River area, Alberta.Alberta Geological Survey, MIN 1995006AlbertaExploration - assessment, Ridgeway Petroleum, Horseshoe Gold Mining
DS1995-1165
1995
Marchand, M.Marchand, M.Diamond exploration in the Peace River area, AlbertaCalgary Mineral Eploration Group, Meeting April 6, 7 Abstract p. 4.AlbertaPeace River area, Geophysics
DS1997-0730
1997
Marchand, M.Marchand, M.Metallic and industrial mineral assessment report on the exploration program Horseshoe project Peace RiverAlberta Geological Survey, MIN 19970005AlbertaExploration - assessment, Ridgeway Petroleum, Horseshoe Gold
DS2003-0468
2003
Marchand, P.Girard, R., Moorhead, J., Marchand, P.Kimberlites in Quebec: current statusQuebec Exploration Conference, Nov. 25-27, 1p. abstractQuebecBrief overview
DS200412-0668
2003
Marchand, P.Girard, R., Moorhead, J., Marchand, P.Kimberlites in Quebec: current status.Quebec Exploration Conference, Nov. 25-27, 1p. abstractCanada, QuebecBrief overview
DS201412-0184
2014
Marchant, D.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, pp. 1790-1794 extended abstractCanada, Northwest TerritoriesGeophysics - Tli Kwi Cho
DS201412-0250
2014
Marchant, D.Fournier, D., Heagy, L., Corcoran, N., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, pp. 1795-1798. Extended abstractCanada, Northwest TerritoriesGeophysics - Tli Kwi Cho complex
DS201501-0006
2014
Marchant, D.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO-18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS201501-0009
2014
Marchant, D.Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS201611-2103
2014
Marchant, D.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, pp. 1790-1794. pdfCanada, Northwest TerritoriesDeposit - Tli Kwi Cho

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO- 18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS201611-2107
2014
Marchant, M.Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Marchant, M., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, pp. 1795-1799. pdfCanada, Northwest TerritoriesDeposit - Tli Kwi Cho

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS200912-0472
2009
Marcheggiani-Croden, V.Marcheggiani-Croden, V., Hunt, L., Stachel, T., Muehlenbachs, K., Eichenberg, D.Diavik boart - unrelated to gem diamond and fibrous coats?37th. Annual Yellowknife Geoscience Forum, Abstracts p. 81-2.Canada, Northwest TerritoriesBoart diamond
DS201212-0319
2012
Marcheggliani-Croden, V.Hunt, L., Marcheggliani-Croden, V., Stachel, T., Muehlenbachs, K., Eichenberg, D.Polycrystalline and fibrous diamonds from the Diavik mine, Canada.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Northwest TerritoriesDeposit - Diavik
DS201802-0252
2017
Marchenko, E.I.Marchenko, E.I., Eremin, N.N., Bychkov, A.Y., Grechanovskii, A.E.Ca and Mg perovskite phases in the Earth's mantle as a probable reservoir of Al: computer simulated evidence.Moscow University Geology Bulletin, Vol. 72, 5, pp. 299-304.Mantleperovskite

Abstract: Semi-empirical and quantum chemical studies of Al atom energy in CaSiO3 and MgSiO3 with the perovskite-type structure at pressures and temperatures of the Earth’s mantle are reported. The phase diagram for CaSiO3 is reproduced and refined. Probable mechanisms of Al incorporation in the structures studied are considered. According to the results of the calculations, Al is preferably incorporated into MgSiO3, rather than into CaSiO3. Evaluation of the isomorphic capacity of perovskite phases in relation to Al shows that the Al content in MgSiO3 may reach 2.4 mol % at 120 GPa and 2400 K. CaSiO3 cannot be a source of Al atoms in the Earth’s mantle.
DS202004-0537
2020
Marchenko, E.I.Tamarova, A.P., Marchenko, E.I., Bobrov, A.V., Eremin, N.N., Zinovera, N.G., Irifune, T., Hirata, T., Makino, Y.Interphase REE partitioning at the boundary between the Earth's transition zone and lower mantle: evidence from experiments and atomistic modeling.Minerals MDPI, Vol. 10, 10030262 14p. PdfMantleREE

Abstract: Trace elements play a significant role in interpretation of different processes in the deep Earth. However, the systematics of interphase rare-earth element (REE) partitioning under the conditions of the uppermost lower mantle are poorly understood. We performed high-pressure experiments to study the phase relations in key solid-phase reactions CaMgSi2O6 = CaSiO3-perovskite + MgSiO3-bridgmanite and (Mg,Fe)2SiO4-ringwoodite = (Mg,Fe)SiO3-bridgmanite + (Mg,Fe)O with addition of 1 wt % of REE oxides. Atomistic modeling was used to obtain more accurate quantitative estimates of the interphase REE partitioning and displayed the ideal model for the high-pressure minerals. HREE (Er, Tm, Yb, and Lu) are mostly accumulated in bridgmanite, while LREE are predominantly redistributed into CaSiO3. On the basis of the results of experiments and atomistic modeling, REE in bridgmanite are clearly divided into two groups (from La to Gd and from Gd to Lu). Interphase REE partition coefficients in solid-state reactions were calculated at 21.5 and 24 GPa for the first time. The new data are applicable for interpretation of the trace-element composition of the lower mantle inclusions in natural diamonds from kimberlite; the experimentally determined effect of pressure on the interphase (bridgmanite/CaSiO3-perovskite) REE partition coefficients can be a potential qualitative geobarometer for mineral inclusions in super-deep diamonds.
DS202009-1632
2020
Marchenko, E.I.Iskrina, A., Spivak, A.V., Bobrov, A.V., Eremin, N.N., Marchenko, E.I., Dubrovinsky, L.S.Synthesis and crystal structures of new high-pressure phases CaAl2O4 and Ca2Al6O11.Lithos, Vol. 374-375, 6p. PdfMantlegarnet

Abstract: The phases of CaAl2O4 and Ca2Al6O11 were synthesized at 15 GPa and 1600 °C. Microprobe data gave formulae Ca1.003Al1.998O4 and Ca2.05Al5.97O11, on the basis of 4 and 11 oxygen atoms. The crystal structures have been refined by single-crystal X-ray diffraction. Orthorhombic unitcell parameters for CaAl2O4 are a = 8.8569(10) Å; b = 2.8561(4) Å; c = 10.2521(11) Å; V = 259.34(5) Å3; Z = 8 (space group Pnma). The Ca2Al6O11 phase was obtained for the first time. It crystallizes with a space group P42/mnm and has lattice parameters a = b = 11.1675(4) Å; c = 2.83180(10) Å; V = 353.16(2) Å3; Z = 2. A Raman spectrum was obtained for a new phase for the first time. Our results suggest that both studied phases are stable under the condition of the transition zone and can be considered as potential aluminum concentrators in the Earth's deep geospheres.
DS1986-0233
1986
Marchenko, E.Ya.Faizullin, R.M., Sadykov, I.S., Marchenko, E.Ya.A geologic and technological model of the carbonatite type of apatite oredepositsSoviet Geology and Geophysics, Vol. 27, No. 11, pp. 24-31RussiaCarbonatite, Apatite
DS1960-0296
1962
Marcher, M.V.Stearns, R.G., Marcher, M.V.Late Cretaceous and Subsequent Structural Development of The Northern Mississippi Embayment Area.Geological Society of America (GSA) Bulletin., Vol. 73, PP. 1387-1394.GlobalMid-continent
DS201112-1081
2010
Marchese, C.Vasconcellos, E.M.G., Lopes, A.P., Fischer, G., Marchese, C., Reis Neto, J.M.Microtomografia de raios x applicada ao estudo de inclusoes em diamantes.5th Brasilian Symposium on Diamond Geology, Nov. 6-12, abstract p. 44-45.South America, BrazilTomography - inclusions
DS201012-0473
2010
Marchesi, C.Marchesi, C., Griffin, W.L., Garrido, C.J., Bodinier, J-L., O'Reilly, S.Y., Pearson, N.J.Persistence of mantle lithospheric Re-Os signature during asthenospherization of the subcontinental lithospheric mantle: insights in situ sulphides....Contributions to Mineralogy and Petrology, Vol. 159, 3, pp. 315-330.Europe, SpainRonda peridotite
DS201312-0320
2013
Marchesi, C.Gonzalez-Jimienez, J.M., Marchesi, C., Griffin, W.L., Gutierrez-Narbona, R., Lorand, J-P., O'Reilly, S.Y., Garrido, C.J., Gervilla, F., Pearson, N.J., Hidas, K.Transfer of Os isotopic signatures from peridotite to chromitite in the subcontinental mantle: insights from in situ analysis of platinum-group and base metal minerals (Ojen peridotite massif, southern Spain.Lithos, Vol. 164-167, pp. 74-85.Europe, SpainChromitite
DS201312-0574
2013
Marchesi, C.Marchesi, C., Garrido, C.J., Bosch, D., Bodinier, J-L., Gervilla, F., Hidas, K.Mantle refertilization by melts of crustal derived garnet pyroxenite: evidence from the Ronda Peridotite massif, southern Spain.Earth and Planetary Interiors, Vol. 362, pp. 66-75.Europe, SpainRonda - pyroxenite. Melts
DS201412-0548
2014
Marchesi, C.Marchesi, C., Dale, C.W., Garrdo, C.J., Pearson, D.G., Bosch, D., Bodinier, J-L., Gervilla, F., Hidas, K.Fractionation of highly siderophile elements in refertilized mantle: implications for the Os isotope composition of basalts.Earth and Planetary Science Letters, Vol. 400, pp. 33-44.MantleRonda peridotite
DS201610-1850
2016
Marchesi, C.Chetoumani, K., Bondinier, J-L., Garrido, C.J., Marchesi, C., Amri, I., Targusiti, K.Spatial variability of pyroxenite layers in the Beni Bousera orogenic peridotite ( Morocco) and implications for their origin.Comptes Rendus Geoscience, in press available 11p.Africa, MoroccoPeridotite

Abstract: The Beni Bousera peridotite contains a diversity of pyroxenite layers. Several studies have postulated that at least some of them represent elongated strips of oceanic lithosphere recycled in the convective mantle. Some pyroxenites were, however, ascribed to igneous crystal segregation or melt-rock reactions. To further constrain the origin of these rocks, we collected 171 samples throughout the massif and examined their variability in relation with the tectono-metamorphic domains. A major finding is that all facies showing clear evidence for a crustal origin are concentrated in a narrow corridor of mylonitized peridotites, along the contact with granulitic country rocks. These peculiar facies were most likely incorporated at the mantle-crust boundary during the orogenic events that culminated in the peridotite exhumation. The other pyroxenites derive from a distinct protolith that was ubiquitous in the massif before its exhumation. They were deeply modified by partial melting and melt-rock reactions associated with lithospheric thinning.
DS201704-0650
2016
Marchesi, C.Varas-Reu, M.I., Garrido, C.J., Marchesi, C., Bodinier, J-L., Frets, E., Bosch, D., Tommasi, A., Hidas, K., Targuisti, K.Refertilization processes of the subcontinental lithospheric mantle: the record of the Beni Bousera orogenic peridotite ( Rif Belt, northern Morocco).Journal of Petrology, Vol. 57, 11-12, pp. 2251-2270.Africa, MoroccoDeposit - Beni Bousera

Abstract: Correlations between major and minor transition elements in tectonically emplaced orogenic peridotites have been ascribed to variable degrees of melt extraction and melt-rock reaction processes, leading to depletion or refertilization. To elucidate how such processes are recorded in the subcontinental lithospheric mantle, we processed a large geochemical dataset for peridotites from the four tectono-metamorphic domains of the Beni Bousera orogenic massif (Rif Belt, northern Morocco). Our study reveals that variations in bulk-rock major and minor elements, Mg-number and modal mineralogy of lherzolites, as well as their clinopyroxene trace element compositions, are inconsistent with simple partial melting and mainly resulted from different reactions between melts and depleted peridotites. Up to 30% melting at <3 GPa and cryptic metasomatism can account for the geochemical variations of most harzburgites. In Grt-Sp mylonites, melting and melt-rock reactions are masked by tectonic mixing with garnet pyroxenites and subsolidus re-equilibration. In the rest of the massif, lherzolites were mostly produced by refertilization of a refractory protolith (Mg-number = 91, Ol = 70%, Cpx/Opx = 0.4) via two distinct near-solidus, melt- rock reactions: (1) clinopyroxene and orthopyroxene precipitation and olivine consumption at melt/rock ratios <0.75 and variable mass ratio between crystallized minerals and infiltrated melt ®, which are recorded fairly homogeneously throughout the massif; (2) dissolution of orthopyroxene and precipitation of clinopyroxene and olivine at melt/rock ratios <1 and R = 0.2-0.3, which affected mainly the Arie` gite-Seiland and Seiland domains. The distribution of secondary lherzolites in the massif suggests that the first refertilization reaction occurred prior to the differentiation of the Beni Bousera mantle section into petro-structural zones, whereas the second reaction was associated with the development of the tectono-metamorphic domains. Our data support a secondary, refertilization-related origin for most lherzolites in orogenic peridotite massifs.
DS201707-1314
2016
Marchesi, C.Chetouani, K., Bodinier, J-L., Garrido, C.J., Marchesi, C., Amri, I., Targuisti, K.Spatial variability of pyroxenite layers in the Beni Bousera orogenic peridotite ( Morocco) and implications for their origin.Comptes Rendus Geoscience, Vol. 348, pp. 619-629.Africa, Moroccoperidotite

Abstract: The Beni Bousera peridotite contains a diversity of pyroxenite layers. Several studies have postulated that at least some of them represent elongated strips of oceanic lithosphere recycled in the convective mantle. Some pyroxenites were, however, ascribed to igneous crystal segregation or melt–rock reactions. To further constrain the origin of these rocks, we collected 171 samples throughout the massif and examined their variability in relation with the tectono-metamorphic domains. A major finding is that all facies showing clear evidence for a crustal origin are concentrated in a narrow corridor of mylonitized peridotites, along the contact with granulitic country rocks. These peculiar facies were most likely incorporated at the mantle–crust boundary during the orogenic events that culminated in the peridotite exhumation. The other pyroxenites derive from a distinct protolith that was ubiquitous in the massif before its exhumation. They were deeply modified by partial melting and melt–rock reactions associated with lithospheric thinning.
DS201806-1258
2018
Marchesi, C.Varas-Reus, M.I., Garrido, C.J., Marchesi, C., Bosch, D., Hidas, K.Genesis of ultra-high pressure garnet pyroxenites in orogenic peridotites and its bearing on the compositional heterogeneity of the Earth's mantle. Ronda, Beni BouseraGeochimica et Cosmochimica Acta, Vol. 232, pp. 303-328.Africa, Morocco, Europe, SpainUHP

Abstract: We present an integrated geochemical study of ultra-high pressure (UHP) garnet pyroxenites from the Ronda and Beni Bousera peridotite massifs (Betic-Rif Belt, westernmost Mediterranean). Based on their Sr-Nd-Pb-Hf isotopic systematics, we classify UHP garnet pyroxenites into three groups: Group A pyroxenites (Al 2 O 3 : 15-17.5 wt. %) have low initial 87 Sr/ 86 Sr, relatively high ? Nd , ? Hf and 206 Pb/ 204 Pb ratios, and variable 207 Pb/ 204 Pb and 208 Pb/ 204 Pb. Group B pyroxenites (Al 2 O 3 < 14 wt. %) are characterized by high initial 87 Sr/ 86 Sr and relatively low ? Nd , ? Hf and 206 Pb/ 204 Pb ratios. Group C pyroxenites (Al 2 O 3 ~ 15 wt. %) have depleted radiogenic signatures with relatively low initial 87 Sr/ 86 Sr and 206 Pb/ 204 Pb, high ? Nd and ? Hf , and their 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios are similar to those of Group B pyroxenites. The major and trace element and isotopic compositions of UHP garnet pyroxenites support their derivation from ancient (1.5-3.5 Ga) oceanic crust recycled into the mantle and intimately stirred with peridotites by convection. However, the genesis of these pyroxenites requires also the involvement of recycled continental lower crust with an isotopic composition akin to the lower crustal section of the lithosphere where these UHP garnet pyroxenites now reside in. These oceanic and continental crustal components were stirred in different proportions in the convective mantle, originating pyroxenites with a more marked geochemical imprint of either oceanic (Group A) or continental lower crust (Group B), or hybrid compositions (Group C). The pyroxenite protoliths likely underwent several melting events, one of them related to the formation of the subcontinental lithospheric mantle and continental crust, generating restitic UHP garnet pyroxenites now preserved in the Ronda and Beni Bousera orogenic peridotites. The extent of melting was mostly 3 controlled by the bulk Mg-number (Mg#) of the pyroxenite protoliths, where protoliths with low Mg# experienced higher degrees of partial melting than sources with higher Mg#. Positive Eu and Sr anomalies in bulk rocks, indicative of their origin from cumulitic crustal gabbros, are preserved mostly in high Mg# pyroxenites due to their higher melting temperatures and consequent lower partial melting degrees. The results of this study show that the genesis of UHP garnet pyroxenites in orogenic peridotites requires a new recipe for the marble cake mantle hypothesis, combining significant recycling and stirring of both oceanic and continental lower crust in the Earth's mantle. Furthermore, this study establishes a firm connection between the isotopic signatures of UHP pyroxenite heterogeneities in the mantle and the continental lower crust.
DS201808-1794
2018
Marchesi, C.Varas-Reu, M.I., Garrido, C.J., Marchesi, C., Bosch, D., Hidas, K.Genesis of ultra high pressure garnet pyroxenites in orogenic peridotites and its bearing on the compositional heterogeneity of the Earth's mantle.Geochimica et Cosmochimica Acta, Vol. 232, pp. 303-328.Mantledeposit - Ronda, Beni Bousera

Abstract: We present an integrated geochemical study of ultra-high pressure (UHP) garnet pyroxenites from the Ronda and Beni Bousera peridotite massifs (Betic-Rif Belt, westernmost Mediterranean). Based on their Sr-Nd-Pb-Hf isotopic systematics, we classify UHP garnet pyroxenites into three groups: Group A pyroxenites (Al2O3: 15-17.5?wt.%) have low initial 87Sr/86Sr, relatively high ?Nd, ?Hf and 206Pb/204Pb ratios, and variable 207Pb/204Pb and 208Pb/204Pb. Group B pyroxenites (Al2O3?
DS201904-0744
2019
Marchesi, C.Hidas, K., Garrido, C.J., Booth-Rea, G., Marchesi, C., Bodinier, J-L., Dautria, J-M., Louni-Hacini, A., Azzouni-Sekkal, A.Lithosphere tearing along STEP faults and synkenetic formation of lherzolite and wehrlite in the shallow subcontinental mantle. OranSolid Earth, https://doi.org/10.5194 /se-2019-32 36p.Mantle, Africa, Algeriasubduction

Abstract: Subduction-Transform Edge Propagator (STEP) faults are the locus of continual lithospheric tearing at slab edges, resulting in sharp changes in the lithospheric and crustal thickness and triggering lateral and/or near-vertical mantle flow. However, the mechanisms at the lithospheric mantle scale are still poorly understood. Here, we present the microstructural study of olivine-rich lherzolite, harzburgite and wehrlite mantle xenoliths from the Oran volcanic field (Tell Atlas, NW Algeria). This alkali volcanic field occurs along a major STEP fault responsible for the Miocene westward slab retreat in the westernmost Mediterranean. Mantle xenoliths provide a unique opportunity to investigate the microstructures in the mantle section of a STEP fault system. The microstructures of mantle xenoliths show a variable grain size ranging from coarse granular to fine-grained equigranular textures uncorrelated with modal variations. The major element composition of the mantle peridotites provides temperature estimates in a wide range (790-1165?°C) but in general, the coarse-grained and fine-grained peridotites suggest deeper and shallower provenance depth, respectively. Olivine grain size in the fine-grained peridotites depends on the size and volume fraction of the pyroxene grains, which is consistent with pinning of olivine grain growth by pyroxenes as second phase particles. In the coarse-grained peridotites, well-developed olivine crystal preferred orientation (CPO) is characterized by orthorhombic and [100]-fiber symmetries, and orthopyroxene has a coherent CPO with that of olivine, suggesting their coeval deformation by dislocation creep at high-temperature. In the fine-grained microstructures, along with the weakening of the fabric strength, olivine CPO symmetry exhibits a shift towards [010]-fiber and the [010]- and [001]-axes of orthopyroxene are generally distributed subparallel to those of olivine. These data are consistent with deformation of olivine in the presence of low amounts of melts and the precipitation of orthopyroxenes from a melt phase. The bulk CPO of clinopyroxene mimics that of orthopyroxene via a topotaxial relationship of the two pyroxenes. This observation points to a melt-related origin of most clinopyroxenes in the Oran mantle xenoliths. The textural and geochemical record of the peridotites are consistent with interaction of a refractory harzburgite protolith with a high-Mg# melt at depth (resulting in the formation of coarse-grained clinopyroxene-rich lherzolite and wehrlite), and with a low-Mg# evolved melt in the shallow subcontinental lithospheric mantle (forming fine-grained harzburgite). We propose that pervasive melt-peridotite reaction - promoted by lateral and/or near-vertical mantle flow associated with lithospheric tearing - resulted in the synkinematic crystallization of secondary lherzolite and wehrlite and played a key effect on grain size reduction during the operation of the Rif-Tell STEP fault. Melt-rock reaction and secondary formation of lherzolite and wehrlite may be widespread in other STEP fault systems worldwide.
DS202008-1396
2020
Marchesi, C.Gonzales-Jiminez, J.M., Tassara, S., Schettino, E., Roque-Rosell, J., Farre-de-Pablo, J., Saunders, J.E., Deditius, A.P., Colas, V., Rovira-Medina, J.J., Guadalupe Davalos, M., Schilling, M., Jiminez-Franco, A., Marchesi, C., Nieto, F., Proenza, J.A., GerMineralogy of the HSE in the subcontinental lithospheric mantle - an interpretive review.Lithos, in press available, 44p. PdfMantleHSE

Abstract: The highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au) exist in solid solution in accessory base-metal sulfides (BMS) as well as nano-to-micron scale minerals in rocks of the subcontinental lithospheric mantle (SCLM). The latter include platinum-group minerals (PGM) and gold minerals, which may vary widely in morphology, composition and distribution. The PGM form isolated grains often associated with larger BMS hosted in residual olivine, located at interstices in between peridotite-forming minerals or more commonly in association with metasomatic minerals (pyroxenes, carbonates, phosphates) and silicate glasses in some peridotite xenoliths. The PGM found inside residual olivine are mainly Os-, Ir- and Ru-rich sulfides and alloys. In contrast, those associated with metasomatic minerals or silicate glasses of peridotite xenoliths consist of Pt, Pd, and Rh bonded with semimetals like As, Te, Bi, and Sn. Nanoscale observations on natural samples along with the results of recent experiments indicate that nucleation of PGM is mainly related with the uptake of HSE by nanoparticles, nanominerals or nanomelts at high temperature (> 900?°C) in both silicate and/or sulfide melts, regardless of the residual or metasomatic origin of their host minerals. A similar interpretation can be assumed for gold minerals. Our observations highlight that nanoscale processes play an important role on the ore-forming potential of primitive mantle-derived magmas parental to magmatic-hydrothermal deposits enriched in noble metals. The metal inventory in these magmas could be related with the physical incorporation of HSE-bearing nanoparticles or nanomelts during processes of partial melting of mantle peridotite and melt migration from the mantle to overlying continental crust.
DS1990-0180
1990
Marchesi, S.Beccaluva, L., Coltori, M., Marchesi, S.Lithospheric oceanic mantle beneath the Canary Islands: evidence from ultramafic xenoliths from LanzaroteTerra, Abstracts of International Workshop Orogenic Lherzolites and Mantle Processes, Vol. 2, December abstracts p. 125GlobalBasanite, Alkaline rocks
DS1991-1055
1991
Marchetto, M.Mariano, A.N., Marchetto, M.Serra Negra and Salitre-carbonatite alkaline igneous complexFifth International Kimberlite Conferences Field Excursion Guidebook, Servico Geologico do Brasil (CPRM) Special, pp. 75-82BrazilCarbonatite, Alkaline rocks
DS1992-0994
1992
Marchev, P.Marchev, P., et al.Petrology of neogene basanites and included ultramafic xenoliths of the Moesian Platform north Bulgaria.Neues Jahrbuch Miner. Abh., Vol. 164, No. 2-3, pp. 113-137.GlobalXenoliths, Basanites
DS201412-0549
2014
Marchi, S.Marchi, S., Bottke, W.F., Elkins-Tanton, M., Bierhaus, K., Wuennemann, A., Morbidelli, Kring, D.A.Wide spread mixing and burial of Earth's Hadean crust by asteroid impacts.Nature, Vol. 511, July 31, pp. 578-582.GlobalGeochronology - zircons
DS201710-2252
2017
Marchi, S.O'Neill, C., Marchi, S., Zhang, S., Bottke, W.Impact driven subduction on the Hadean Earth.Nature Geoscience, Vol. 10, 10, pp. 793-797.Mantlesubduction

Abstract: Impact cratering was a dominant geologic process in the early Solar System that probably played an active role in the crustal evolution of the young terrestrial planets. The Earth’s interior during the Hadean, 4.56 to 4 billion years ago, may have been too hot to sustain plate tectonics. However, whether large impacts could have triggered tectonism on the early Earth remains unclear. Here we conduct global-scale tectonic simulations of the evolution of the Earth through the Hadean eon under variable impact fluxes. Our simulations show that the thermal anomalies produced by large impacts induce mantle upwellings that are capable of driving transient subduction events. Furthermore, we find that moderate-sized impacts can act as subduction triggers by causing localized lithospheric thinning and mantle upwelling, and modulate tectonic activity. In contrast to contemporary subduction, the simulated localized subduction events are relatively short-lived (less than 10?Myr) with relatively thin, weak plates. We suggest that resurgence in subduction activity induced by an increased impact flux between 4.1 and 4.0 billion years ago may explain the coincident increase in palaeointensity of the magnetic field. We further suggest that transient impact-driven subduction reconciles evidence from Hadean zircons for tectonic activity with other lines of evidence consistent with an Earth that was largely tectonically stagnant from the Hadean into the Archaean.
DS1989-1509
1989
Marchildon, N.Trcienski, W.E., Marchildon, N.Kyanite-garnet bearing Cambrian rocks and Grenvilleg ranulites from theAyer's Cliff, Quebec, Canada,lamprophyre dike suite: deep crustal fragmentsGeology, Vol. 17, No. 7, July pp. 637-640QuebecLamprophyre
DS1993-0548
1993
Marchildon, N.Girard, R., Birkett, T., Moorhead, J., Marchildon, N.Geologie de la region de Press ClovaQuebec Department of Mines, MB 93-04, 54p.QuebecGeology
DS1992-0125
1992
Marchilfon, N.Birkett, T.C., Girard, R., Moorhead, J., Marchilfon, N.Carte geologique de la Province Grenville a l'est de l'axe LouvicourtVald'Or Senneterre.Quebec Department of Mines, MB 92-15, 15p.QuebecMap - geology
DS2001-0169
2001
Marcia, K.Challis, J., Marcia, K.The Star kimberlite 2001Saskatchewan Open House abstracts, Nov. p.55.SaskatchewanNews item, Shore Gold
DS2003-0651
2003
Marcia, K.Jellicoe, B.C., Zonnenveld, J.P., Marcia, K.Discovery and evolution of exploration methods at the Fort a la Corne kimberlite fieldGeological Association of Canada Annual Meeting, Abstract onlySaskatchewanTechniques
DS200412-0910
2003
Marcia, K.Jellicoe, B.C., Zonnenveld, J.P., Marcia, K.Discovery and evolution of exploration methods at the Fort a la Corne kimberlite field, Saskatchewan.Geological Association of Canada Annual Meeting, Abstract onlyCanada, SaskatchewanTechniques
DS2002-0993
2002
Marcia, K.Y.Marcia, K.Y., Chalis, J.The Diamondiferous Star kimberlite - a completely preserved kimberlite volcanoGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.73., p.73.SaskatchewanGeochemistry - petrology
DS2002-0994
2002
Marcia, K.Y.Marcia, K.Y., Chalis, J.The Diamondiferous Star kimberlite - a completely preserved kimberlite volcanoGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.73., p.73.SaskatchewanGeochemistry - petrology
DS2003-1566
2003
Marcia, K.Y.Zonneveld, J.P., Kjarsgaard, B.A., Harvey, S.E., Marcia, K.Y., McNeil, D.Sedimentologic and stratigrahic constraints on emplacement of the Star kimberlite, east8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractSaskatchewanGeology, economics, Deposit - Star
DS200412-2238
2003
Marcia, K.Y.Zonneveld, J.P., Kjarsgaard, B.A., Harvey, S.E., Marcia, K.Y., McNeil, D., Heaman, L.M., White, D.J.Sedimentologic and stratigrahic constraints on emplacement of the Star kimberlite, east central Saskatchewan.8 IKC Program, Session 1, AbstractCanada, SaskatchewanGeology, economics Deposit - Star
DS202008-1382
2020
Marcon, V.H.Conceicao, R.V., Marcon, V.H., Souza, M.R.W., Carniel, L.C., Quinteiro, R.V.S., Rovani, P., Mizusaki, A.M.P., Spitzenberger, M.S.Carbonatite/lamproite liquid imissibility in the Earth's mantle through the nefeline-diopside-kalsilite+-CO2, CH4, H2O diagram.Goldschmidt 2020, 1p. AbstractMantlelamproite

Abstract: The presence and speciation of volatile C-H-O elements in the silicate systems play an important role in the genesis of magmas on the Earth’s mantle, due to the fact that these elements, mainly in the form of H2O, CO2, CH4 and CxHy, decrease the solidi temperatures of source rocks, making magmatism possible in Earth’s present day thermal conditions [1]. Among those elements, carbon is the only element that changes its valence according to the oxygen fugacity (fO2) conditions of the environment, resulting in different speciation, as: CO3 -2, CO2, Cgraphite/diamond, CH4 or heavier hydrocarbons. In the present work, we are determining phase stability of minerals, water, CO2 and CH4 in the system Nefeline-Kalsilite-Diopside. Our experiments are conducted under 4.0 GPa and temperatures up to 1300°C, using a 1000 tonf hydraulic press coupled with toroidal chambers. Preliminary experiments performed at 1300°C and 4.0GPa (initial composition in the Olivine-Quartz- Kalsalite/Nepheline system: 40mol% Ol90, 40mol% Nph50Kls50 and 20mol% Qz, PH2O,CO2=Ptotal) resulted in the formation of forsterite (Fo90) in equilibrium with phlogopite (Phl), melt and volatile phases (CO2 and CH4). Closer to the Diopside vertice, the addition of CO3 to the sample resulted in a imisibility of a carbonatitic and a silicatic melt, in which the carbonititic melt is enriched in sodium, while the silcate melt is enriched in potassium. Appart from that, experiments in different parts of the diagram suggest compositions from nephelinite-kalsilitite to lamproites composition for the silicate melt in equilibrium with diopside (solid solution with omphacite) and phlogopite. This work is a continuation of previous work in the anhydrous diagram and future works will provide the addition of CH4 as the volatile phase
DS201901-0072
2018
Marcondes, M.L.Santos, S.S.M., Marcondes, M.L., Justo, J.F., Assali, L.V.C.Stability of calcium and magnesium carbonates at Earth's lower mantle thermodynamic conditions.Earth and Planetary Science Letters, Vol. 506, pp. 1-7.Mantlegeodynamics

Abstract: We present a theoretical investigation, based on ab initio calculations and the quasi-harmonic approximation, on the stability properties of magnesium (MgCO3) and calcium (CaCO3) carbonates at high temperatures and pressures. The results indicate that those carbonates should be stable in the Earth's lower mantle, instead of dissociating into other minerals, in chemical environments with excess of SiO2, MgO, or MgSiO3. Therefore, considering the lower mantle chemical composition, consisting mostly of the MgSiO3 and MgO minerals, calcium and magnesium carbonates are the primary candidates as carbon hosts in that region. For the thermodynamic conditions of the mantle, the results also indicate that carbon should be primarily hosted on MgCO3, contrasting with what was found by other theoretical studies, which neglected temperature effects. Finally, the results indicate that carbon, in the form of free CO2, is unlikely in the lower mantle.
DS1991-0157
1991
Marcotte, D.Bourgault, G., Marcotte, D.Multivariable variogram and its application to the linear model ofcoregionalizationMath. Geol, Vol. 23, No. 7, pp. 899-928GlobalGeostatistics, Variograms
DS1991-1049
1991
Marcotte, D.Marcotte, D.Cokriging with MatlabComputers and Geosciences, Vol. 17, No. 9, pp. 1265-1280GlobalComputer, Program -Matlab
DS1992-0150
1992
Marcotte, D.Bourgault, G., Marcotte, D., Legendre, P.The multivariate (Co) variogram as a spatial weighting function in classification methodsMathematical Geology, Vol. 24, No. 4, pp. 463-478GlobalComputer, cobalt, Program -Multivariate variograM.
DS1992-1224
1992
Marcotte, D.Posa, D., Marcotte, D.Robustness of kriging weights to non-bias conditionsMathematical Geology, Vol. 24, No. 7, pp. 759-774GlobalGeostatistics, Kriging
DS1995-0068
1995
Marcotte, D.Asli, M., Marcotte, D.Comparison of approaches to spatial estimation in a bivariate contextMathematical Geology, Vol. 27, No. 5, pp. 641-658OntarioGeostatistics, Volcanics
DS1995-1166
1995
Marcotte, D.Marcotte, D.Generalized cross validation for covariance model selectionMathematical Geology, Vol. 27, No. 5, pp. 659-672GlobalGeostatistics
DS1997-0731
1997
Marcotte, D.Marcotte, D., Groleau, P.A simple and robust log normal estimatorMath. Geol, Vol. 29, No. 8, Nov. pp. 993-1010GlobalComputer, Lognormal, geostatistics
DS201012-0324
2010
Marcotte, D.Ji, S., Quia,S.S., Marcotte, D.Lam parameters of common rocks in the Earth's crust and upper mantle.Journal of Geophysical Research, Vol. 115, B6, B06314.MantleGeophysics - seismics
DS1992-0995
1992
Marcotte, D.L.Marcotte, D.L., Hardwicke, C.D., Nelson, J.B.Automated interpretation of horizontal magnetic gradient profile dataGeophysics, Vol. 57, No. 2, February pp. 288-295GlobalGeophysics, Magnetics
DS2002-0608
2002
MarcouxGrancea, L., Bailly, L., Leroy, Banks, Marcoux, MilisiFluid evolution in the Baia Mare epithermal gold/polymetallic district, Inner CarpathiansMineralium deposita, RomaniaGold, copper, zinc, Deposit - Baia Mare
DS1993-0972
1993
Marcoux, E.Marcoux, E., Milesi, J.P.Lead isotope signature of Early Proterozoic ore deposits in Western Africa:comparison with gold deposits in French GuianaEconomic Geology, Vol. 88, No. 7, November pp. 1862-1879West AfricaGeochronology, Deposits -regional geology
DS1990-0981
1990
Marcus, J.Marcus, J.Mining environment - California exampleEngineering and Mining Journal, Vol. 191, No. 7, July pp. 16E, G, I, J.CaliforniaMining, Environment -legal
DS1990-0982
1990
Marcus, J.Marcus, J.Mining environment -financial ratios for mine analysisEngineering and Mining Journal, Vol. 191, No. 9, September pp. 16CC, 16EE, 16GG, 16II, 16KKUnited StatesLegal, Economics -mining environment
DS1990-0983
1990
Marcus, J.Marcus, J.Mining environment -financial assurances for mine closure; a discussion Of the issuesEngineering and Mining Journal, Vol. 191, No. 8, August pp. 16E, g, i, kUnited StatesLegal, Mining environment
DS1990-0984
1990
Marcus, J.Marcus, J.Mining enviornment- regulatory control of mining at the federal level, partoneEngineering and Mining Journal, Vol. 191, No. 6, June p. 16U, W, Y, Z, 16AA, BB.United StatesMining, Environment
DS1996-0885
1996
Marcus, J.J.Marcus, J.J.A long needed tome, , ,the mining environmental handbook.BriefdescriptionEngineering and Mining Journal, Vol. 197, No. 10, Oct. pp. 37, 39, 40, 42United StatesEnvironment, Mining industry book
DS1997-0732
1997
Marcus, J.J.Marcus, J.J.Mining environmental handbookImperial College Press, SummerGlobalBook - ad, Environment
DS202106-0958
2021
Mare, E.R.Mikhail, S., Rinaldi, M., Mare, E.R., Sverjensky, D.A.A genetic metasomatic link between eclogitic and peridotitc diamond inclusions.Geochemical Perspectives Letters, Vol. 17, pp. 33-38. pdfMantlediamond inclusions

Abstract: Diamond inclusions sample the otherwise inaccessible archive of Earth’s deep interior. The geochemical and petrological diversity of diamond inclusions reflects either pre-metasomatic upper mantle heterogeneity or metasomatism coeval with diamond formation. We focus on the origin of lithospheric garnet and clinopyroxene inclusions by simulating metasomatic reactions between eclogitic fluids and mantle peridotites at 5 GPa, 1000 °C, and across a range of redox conditions (logfO2?=??1 to ?6 ?FMQ). Our results demonstrate that fluid-rock interaction can result in the formation of eclogitic, websteritic, and peridotitic silicates from a single fluid during a single diamond-forming metasomatic event. Ergo, the petrogenesis of diamond and their inclusions can be syngenetic, and the petrological diversity of diamond inclusions can reflect metasomatism coeval with diamond formation. Furthermore, during the metasomatism, refractory peridotite can be converted to fertile websterite which could become a pyroxenitic mantle source for oceanic basalts.
DS1997-0733
1997
Mare, L.P.Mare, L.P., Thomas, R.J.Paleomagnetism and aeromagnetic modelling of the Mesoproterozoic Ntimbankulu Pluton, KwaZulu-Natal.Journal of African Earth Sciences, Vol. 25, No. 4, Nov. pp. 519-538.South AfricaDiapirs, Geophysics - palemagnetics
DS1960-0705
1966
Maree, B.D.Maree, B.D.Die Voorkoms Van Diamante Op Land En Onder die See Langs Die Weskus Van Suidelike Afrika.Tegnikon., Vol. 15, No. 4, PP. 149-159.South Africa, Southwest Africa, NamibiaLittoral Diamond Placers, Submarine
DS1993-0936
1993
Mareiche, A.M.Lukyanova, L.I., Derevyan, I.V., Mareiche, A.M., Dymnikov, W.G.On manifestation of Mesozoic ultra potassium magmatism and prospects of diamond bearing of Chernyshev Range district, Polar Urals.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 330, No. 5, June pp. 617-619.Russia, Commonwealth of Independent States (CIS), UralsAlkaline rocks, Ultrapotassic
DS1995-1124
1995
Mareichev, A.M.Lukyanova, L.I., Derevyanko, I.V., Mareichev, A.M., et al.Mesozoic ultrapotassic igneous rocks and the diamond potential of the Chernyshev Ridge area, Polar Urals.Doklady Academy of Sciences Acad. Science Russia, Vol. 331, No. 5, May pp. 107-110.Russia, UralsAlkaline rocks, Deposit -Chernyshev Ridge area
DS1995-1125
1995
Mareichev, A.M.Lukyanova, L.I., Mareichev, A.M., Kuznetsov, G.P.Prospects for discovery of primary diamond deposits in the Urals and the eastern Russian PlatformMineral Resources of Russia, abstracts, Oct. 1994, pp. 19-23.Russia, UralsProspecting, Diamonds
DS2000-0614
2000
Marek, R.Marek, R.Paleozoic structures at the margin of Baltic Shield rvealed by new / reprocessed marine reflection seismicTectonophysics, Vol. 327, No. 3-4, Dec.15, pp. 293-310.Scandinavia, Baltic ShieldGeophysics - seismic, Tectonics
DS1975-0237
1976
Marenga, B.S.I.Baldock, J.W., Hepworth, J.V., Marenga, B.S.I.Gold, Base Metals and Diamonds in BotswanaEconomic Geology, Vol. 71, No. 1, PP. 139-152;BotswanaKimberlite, Orapa
DS1975-0455
1977
Marengwa, B.S.I.Baldock, J.W., Hepworth, J.V., Marengwa, B.S.I.Resource Inventory of BotswanaBotswana Geological Survey, Vol. 4, 69P. PP. 49-57. (DIAMONDS).BotswanaKimberlite, Diamond Prospecting
DS1981-0282
1981
Marensi de moura, O.J.Marensi de moura, O.J., et al.Gemas de Minas GeraisBelo Horizonte: Metannig, BrazilKimberlite, Kimberley, Janlib, Gemology
DS1996-0886
1996
Mares, V.M.Mares, V.M.Kinematics of the Kimberley Arc: linear indicators of movement direction of rocks and their tectonics....Geological Society of Australia 13th. Convention held Feb., No. 41, abstracts p.267.AustraliaTectonics -lineaments, Kimberley Arc
DS200412-0908
2003
Marescahl, J.C.Jaupart, C., Marescahl, J.C.Constraints on crustal heat production from heat flow data.Treatise on Geochemistry, Holland Editor, Volume 3, pp. 65-84.MantleGeothermometry
DS200512-0038
2004
Marescahl, J.C.Audet, P., Marescahl, J.C.Anisotropy of the flexural response of the lithosphere in the Canadian Shield.Geophysical Research Letters, Vol. 31, 20, Oct. 28, DOI 10.1029/2004GLO21080Canada, Northwest Territories, Alberta, Saskatchewan, OntarioGeophysics
DS1990-0216
1990
Maresch, W.V.Bocchio, R., De Capitani, L., Liborio, G., Maresch, W.V., MottanaThe eclogite bearing series of Isla Margarita, Venezuela: geochemistry of metabasic lithologies in the la Rinconada and Juan Griego GroupsLithos, Vol. 25, No. 1-3, November pp. 55-70VenezuelaEclogites, Geochemistry
DS2002-0555
2002
Maresch, W.V.Gerya, T.V., Maresch, W.V., Willner, A.P.Lithospheric detachment and slab breakoff under the Variscan collisional orogen: keys to the origin of diamond bearing crustal rocks in the Bohemmian Massif.18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.218.Europe, GermanyDiamond - bearing quartzo-feldspathic
DS2002-0556
2002
Maresch, W.V.Gerya, T.V., Perchuk, L.L., Maresch, W.V., Willner, A.P., Van ReenenThermal regime and gravitational instability of multi layered continental crust:European Journal of Mineralogy, Vol. 14,4,pp. 687-700.MantleUHP - not specific to diamonds
DS200412-0653
2003
Maresch, W.V.Gerya, T.V., Uken, R., Reinhardt, J., Watkeys, M.K., Maresch, W.V., Clarke, B.M.Cold fingers in a hot magma: numerical modeling of country rock diapirs in the Bushveld Complex, South Africa.Geology, Vol. 31, 9, pp. 753-6.Africa, South AfricaDiapirism, magmatism, plumes, subduction zones
DS200612-1073
2005
Maresch, W.V.Perchuk, A.L., Burchard, M., Maresch, W.V., Schertl, H-P.Fluid mediated modification of garnet interiors under ultrahigh pressure conditions.Terra Nova, Vol. 17, 6, pp. 545-553.MantleUHP
DS201012-0573
2009
Maresch, W.V.Perchuk, A.L., Davydova, V.V., Burchard, M., Maresch, W.V., Schertl, H.P., Yapaskurt, V.O., Safonov, O.G.Modification of mineral inclusions in garnet under high pressure conditions: experimental simulation and application to carbonate silicate rocks of KokchetetavRussian Geology and Geophysics, Vol. 50, 12, pp. 1153-1168.RussiaMineralogy
DS1996-0695
1996
MareschalJones, A.G., Eaton, D.W., White, D., Bostock, M., MareschalGeophysical measurements for lithospheric parametersGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 243-250.Canada, mantleGeophysics -seismics, Lithosphere
DS1999-0733
1999
MareschalTelmat, H., Mareschal, J-C, Gariepy, C.The gravity field over Ungava Bay region from satellite altimitry and newland based data: implications geologyCanadian Journal of Earth Sciences, Vol. 36, No. 1, Jan. pp. 75-89.Quebec, Labrador, UngavaGeophysics - gravity
DS2000-0950
2000
MareschalTelmat, H., Mareschal, Gariepy, David, AntonukCrustal models of the eastern Superior Province, Quebec, derived from new gravity data.Canadian Journal of Earth Sciences, Vol.37, No.2-3, Feb.Mar, pp.385-97.QuebecGeophysics - gravity, Tectonics - Superior
DS1989-0876
1989
Mareschal, J.C.LeQuentrec, M.F., Mareschal, J.C., Parphenuk, O.A finite element model of the thermal evolution of theKapuskasingstructureGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A103. (abstract.)OntarioTectonics, Kapuskasing Lithoprobe
DS1989-0934
1989
Mareschal, J.C.Mareschal, J.C., Hamdani, Y., Jessup, D.M.Downward continuation of heat flow dataTectonophysics, Vol. 164, No. 2-4, August 1, pp. 129-138GlobalMantle, Crust -heat flow
DS1989-0935
1989
Mareschal, J.C.Mareschal, J.C., Pinet, C., Gariepy, C., Jaupart, C., Bienfait, G., DallaNew heat flow density and radiogenic heat productiondat a in the Canadian Shield and the QuebecAppalachiansCanadian Journal of Earth Sciences, Vol. 26, No. 4, April pp. 845-852QuebecCraton, Heat Flow
DS1991-1050
1991
Mareschal, J.C.Mareschal, J.C.Downward continuation of heat flow density dat a and thermal regime In eastern CanadaTectonophysics, Vol. 194, No. 4, August 10, pp. 349-356AppalachiaGeothermometry, Heat flow
DS1991-1051
1991
Mareschal, J.C.Mareschal, J.C., Gliko, A.Lithospheric thinning uplift, and heat flow preceding riftingTectonophysics, Vol. 197, No. 2-4, November pp. 117-126MantleGeodynamics, Rift system, heat flow
DS1992-1382
1992
Mareschal, J.C.Shen, P.Y., Wang, K., Beltrami, H., Mareschal, J.C.Paleoclimate change and heat flow density inferred from temperate dat a In the Superior province of the Canadian ShieldPaleogeography, paleoclimatology, paleoecology, Vol. 98, No. 2-4, December pp. 143-166Canada, OntarioHeat flow, Paleoclimates
DS1997-1148
1997
Mareschal, J.C.Telmat, H., Antonuk, C.N., Mareschal, J.C.Gravity modelling along a lithoprobe seismic traverse, northern Grenvilleprovince, western Quebec.Canadian Journal of Earth Sciences, Vol. 34, pp. 127-34.Quebec, LabradorGrenville area
DS1998-0688
1998
Mareschal, J.C.Jaupert, C., Mareschal, J.C., Davaille, A.Heat flow and thickness of the lithosphere in the Canadian ShieldJournal of Geophysical Research, Vol. 103, No. 7, Jul. 10, pp. 15269-86.Northwest Territories, Manitoba, Saskatchewan, AlbertaHeat flow, Mantle
DS1998-0941
1998
Mareschal, J.C.Mareschal, J.C., Gillou-Frottier, L., Cheng, L.Z.Heat flow in the Trans Hudson OrogenGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Abstract Volume, p. A117. abstract.ManitobaGeothermometry - heat flow, Trans Hudson Orogen
DS1998-1459
1998
Mareschal, J.C.Telmat, H., Mareschal, J.C., Gariepy, C., David, J.Crustal models of the northern Superior Province, Quebec, derived from new gravity data.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Abstract Volume, p. A183. abstract.QuebecGeophysics - gravity, Nemiscau, la Grande regions
DS1999-0335
1999
Mareschal, J.C.Jaupart, C., Mareschal, J.C.The thermal structure and thickness of continental rootsLithos, Vol. 48, No. 1-4, Sept. pp. 93-114.MantleGeothermometry, Craton
DS1999-0732
1999
Mareschal, J.C.Telmat, H., Mareschal, J.C., Gariepy, C.The gravity field over the Ungava Bay region from satellite altimetry and new land based data:Canadian Journal of Earth Sciences, Vol. 36, pp. 75-89.Quebec, Labrador, Ungavageophysics - seismic, Leaf Bay - George River
DS1999-0781
1999
Mareschal, J.C.Wang, Y., Mareschal, J.C.Elastic thickness of the lithosphere in the central Canadian shieldGeophysical Research Letters, Vol. 26, No. 19, Oct. 1, pp. 3033-36.Ontario, Manitoba, SaskatchewanLithosphere, Crust
DS2000-0615
2000
Mareschal, J.C.Mareschal, J.C., Jaupart, Gariepy, Cheng et al.Heat flow and deep thermal structure near the southeastern edge of the Canadian Shield.Canadian Journal of Earth Sciences, Vol.37, No.2-3, Feb.Mar, pp.399-414.QuebecGeothermometry, Tectonics
DS2002-0194
2002
Mareschal, J.C.Bourlon, E., Mareschal, J.C., Roest, W.R., Telmat, H.Geophysics correlations in the Ungava Bay areaCanadian Journal of Earth Science, Vol.39,5, May, pp.625-37.Quebec, Labrador, Baffin IslandGeophysics - gravity, magnetics, Tectonics
DS2002-0284
2002
Mareschal, J.C.Cheng, L.Z., Mareschal, J.C., Jaupart, C., Rolandone, F., Gariepy, C., RadigonSimultaneous inversion of gravity and heat flow data: constraints on thermal regimeJournal of Geodynamics, Vol. 34, 1, pp. 11-30.Ontario, ManitobaGeothermometry, Lithosphere - Abitibi subprovince, Thompson Belt
DS2002-1355
2002
Mareschal, J.C.Rolandone, F., Jaupart, C., Mareschal, J.C., Gariepy, C., Bienfait, G., CarbonneSurface heat flow, crustal temperatures and mantle heat flow in the Proterozoic TransJournal of Geophysical Research, Vol. 107, No. 12, Dec. 12, 10.1029/2001JB000698Northwest Territories, Alberta, Saskatchewan, OntarioGeothermometry, Heat flow - tectonics
DS2003-1177
2003
Mareschal, J.C.Rolandone, F., Mareschal, J.C., Jaupart, C., Gariepy, C., Bienfait, G., CarbonneSurface heat flow, crustal temperatures and mantle heat flow in the Proterozoic TransJournal of Geophysical Research, Vol. 107, 12, Dec. 6, pp. DO1 10.1029/2001JB000698OntarioGeothermometry
DS2003-1178
2003
Mareschal, J.C.Rolandone, F., Mareschal, J.C., Jaupart, C., Gosselin, C., Bienfait, G., LapointeHeat flow in the western Superior province of the Canadian ShieldJournal of Geophysical Research, Vol. 30, 12, June 15, 10.1029/2003GLO17386Ontario, Manitoba, SaskatchewanGeothermometry
DS200412-1224
2004
Mareschal, J.C.Mareschal, J.C., Jaupart, C.Variations of surface heat flow and lithospheric thermal structure beneath the North American craton.Earth and Planetary Science Letters, Vol. 223, 1-2, pp. 65-77.Canada, Northwest TerritoriesGeothermometry
DS200412-1682
2003
Mareschal, J.C.Rolandone, F., Mareschal, J.C., Jaupart, C., Gariepy, C., Bienfait, G., Carbonne, C., Lapointe, R.Surface heat flow, crustal temperatures and mantle heat flow in the Proterozoic Trans Hudson Orogen, Canadian Shield.Journal of Geophysical Research, Vol. 107, 12, Dec. 6, pp. DO1 10.1029/2001 JB000698Canada, OntarioGeothermometry
DS200412-1683
2003
Mareschal, J.C.Rolandone, F., Mareschal, J.C., Jaupart, C., Gosselin, C., Bienfait, G., Lapointe, R.Heat flow in the western Superior province of the Canadian Shield.Journal of Geophysical Research, Vol. 30, 12, June 15, 10.1029/2003 GLO17386Canada, Ontario, Manitoba, SaskatchewanGeothermometry
DS200512-0686
2005
Mareschal, J.C.Mareschal, J.C., Jaupart, C., Rolandone, F., Gariepy, C., Fowler, C.M., Bienfait, G., Carbonne, C., Lapointe, R.Heat flow, thermal regime, and elastic thickness of the lithosphere in the Trans-Hudson Orogen.Canadian Journal of Earth Sciences, Vol. 42, 4, April pp. 517-532.Canada, Northwest TerritoriesGeothermometry
DS200512-0846
2004
Mareschal, J.C.Perry, H.K.C., Jaupart, C., Mareschal, J.C., Rolandone, F., Bienfait, G.Heat flow in the Nipigon arm of the Keweenawan Rift, northwestern Ontario, Canada.Geophysical Research Letters, Vol. 31, 15,, L15607, DOI 1029/2004 GL020159Canada, OntarioGeothermometry
DS200612-1078
2006
Mareschal, J.C.Perry, H.K.C., Jaupart, C., Mareschal, J.C., Bienfait, G.Crustal heat production in the Superior Province Canadian Shield and in North America inferred from heat flow data.Journal of Geophysical Research, Vol. 111, B4, B04401.Canada, Ontario, ManitobaGeothermometry
DS200612-1079
2006
Mareschal, J.C.Perry, H.K.C., Jaupart, C., Mareschal, J.C., Shapiro, N.M.Upper mantle velocity temperature conversion and composition determined from seismic refraction and heat flow.Journal of Geophysical Research, Vol. 111, B7 B07301MantleGeophysics - seismics
DS200612-1080
2006
Mareschal, J.C.Perry, H.K.C., Jaupart, C., Mareschal, J.C., Shapiro, N.M.Upper mantle velocity temperature conversion and composition determined from seismic.Journal of Geophysical Research, Vol. 111, B7, July 6, B07301, 14p.Mantle, Canada, OntarioGeophysics - seismics, Superior Province
DS200912-0499
2009
Mareschal, J.C.Michaut, C., Jaupart, C., Mareschal, J.C.Thermal evolution of cratonic roots.Lithos, Vol. 109, 1-2, pp. 47-60.MantleGeothermometry
DS1991-1355
1991
Mareschal, J-C.Pinet, C., Jaupart, C., Mareschal, J-C., Gariepy, C., Bienfait, G.Heat flow and structure of the lithosphere in the eastern Canadian shieldJournal of Geophysical Research, Vol. 96, No. B12, November 10, pp. 19, 941-19, 963OntarioHeat flow, Crust, greenstone belts
DS200612-0120
2005
Mareschal, J-C.Benn, K., Mareschal, J-C., Condie, K.C.Seismic reflection profiles across Archean Cratons.Benn, K., Mareschal, J-C., Condie, K.C. Archean Geodynamics and Environments, AGU Geophysical Monograph, No. 164, p. 264 - foldouts 1 and 2MantleGeophysics - seismic reflection profiles Archean craton
DS200612-0865
2005
Mareschal, J-C.Mareschal, J-C., Jaupart, C.Archean thermal regime and stabilization of the Craton.Benn, K., Mareschal, J-C., Condie, K.C. Archean Geodynamics and Environments, AGU Geophysical Monograph, No. 164, pp. 61-74.MantleGeothermometry
DS200612-0866
2006
Mareschal, J-C.Mareschal, J-C., Jaupart, C., Perry, H.K.C.Crustal evolution in North America recorded in heat production.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 12, abstract only.Mantle, North AmericaGeothermometry
DS200612-1081
2006
Mareschal, J-C.Perry, H.K.C., Jaupart, C., Mareschal, J-C., Bienfait, G.Crustal heat production in the Superior Province, Canadian Shield, and in North America.Journal of Geophysical Research, Vol. 111, No. B4, B04401Canada, Ontario, Manitoba, Saskatchewan, AlbertaGeothermometry
DS200612-1082
2006
Mareschal, J-C.Perry, H.K.C., Mareschal, J-C., Jaupart, C.Variations of strength and localized deformation in cratons: the 1.9 Ga Kapuskasing Uplift, Superior Province, Canada.Earth and Planetary Science Letters, In press - availableCanada, Ontario, ManitobaGeothermometry, craton, structural zone
DS201012-0437
2010
Mareschal, J-C.Levy, F., Jaupart, C., Mareschal, J-C., Bienfait, G., Limare, A.Low heat flux and large variations of lithospheric thickness in the Canadian Shield.Journal of Geophysical Research, Vol. 115, B6, B06404.CanadaGeophysics - seismics
DS201112-0479
2010
Mareschal, J-C.Jaupart, C., Mareschal, J-C.Heat generation and transport in the Earth.cambridge.org/us/earth, 978-0-521-89488-3 476p. $ 75.00GlobalBook - advertisement
DS201112-0883
2011
Mareschal, J-C.Roy, S., Mareschal, J-C.Constraints on the deep thermal structure of the Dharwar craton, India, from heat flow, shear wave velocities and mantle xenoliths.Journal of Geophysical Research, Vol. 116, B2, B02409.IndiaGeothermometry
DS201312-0575
2013
Mareschal, J-C.Mareschal, J-C., Jaupart, V.Radiogenic heat production, thermal regime and evolution of continental crust.Tectonophysics, Vol. 609, pp. 524-534.MantleGeothermometry
DS201609-1723
2016
Mareschal, J-C.Jaupart, C., Mareschal, J-C., Iarotsky, L.Radiogenic heat production in the continental crust.Lithos, Vol. 262, pp. 398-427.MantleThermometry

Abstract: Heat flow and heat production data complement seismic information and provide strong constraints on crustal composition, thickness and evolution. They have helped understand the nature of the Mohorovicic discontinuity and the variations in seismic velocities below the Moho. Notably, heat flow studies have delineated the vertical distribution of heat producing elements throughout the crust and in the upper most mantle lithosphere. Analysis of global data sets on heat flow and crustal thickness demonstrate that there is no correlation between these two variables. This is due to the large spatial variations in crustal composition and heat production that exist within a single geological province. For a given crustal thickness, the Moho temperature varies within a wide range (? 300 K) depending on surface heat flux and crustal heat production. Thus one cannot use generic models based on a “type” crustal column to calculate crustal geotherms. In stable regions, lower crustal temperatures depend on the amount and vertical distribution of heat producing elements in the crust. These temperatures determine the conditions of crustal stability and impose a limit on the maximum thickness of a stabilized crust.
DS201905-1048
2018
Mareschal, J-C.Jaupart, C., Mareschal, J-C., Roman, A.The formation of continental crust from a physics perspective.Geochemistry International, Vol. 56, 13, pp. 1289-1321.Mantlegeophysics

Abstract: The generation of crustal material and the formation of continental crust with a thickness of ?40 km involve different physical mechanisms operating over different time-scales and length-scales. This review focusses on the building of a thick crustal assemblage and on the vertical dimension where the consequences of gravity-driven processes are expressed most clearly. Continental crustal material is produced by a sequence of crust and mantle mlelting, fractionation of basaltic melts and sinking of dense mafic cumulates. The repeated operation of these mechanisms over tens of million years leads to a thick stably stratified crust. We evaluate the main mechanisms involved from a physics perspective and identify the key controls and constraints, with special attention to thermal requirements. To form magma reservoirs able to process significant magma volumes and to allow the foundering of mafic cumulates, melt must be fed locally at rates that are larger than that of average crustal growth. This requires the temporary focussing of magmatic activity in a few centers. In some cases, foundering of dense cumulates does not go to completion, leaving a deformed residual body bearing tell-tale traces of the process. Crust must be thicker than a threshold value in a 30-45 km range for mafic cumulates to sink into the mantle below the crust. Once that threshold thickness has been reached, further additions lead to increase the proportion of felsic material in the crust at the expense of mafic lithologies which disappear from the crust. This acts to enhance radiogenic heat production in the crust. One consequence is that crustal temperatures can be kept at high values in times of diminished melt input and also when magmatic activity stops altogether, which may lead to post-orogenic intracrustal melting and differentiation. Another consequence is that the crust becomes too weak mechanically to withstand the elevation difference with neighbouring terranes, which sets a limit on crustal thickening. The thermal structure of the evolving crust is a key constraint on the overall process and depends strongly on radiogenic heat production, which is surely one of the properties that make continental crust very distinctive. In the Archean Superior Province, Canada, the formation of juvenile continental crust and its thermal maturation 2.7 Gy ago can be tracked quite accurately and reproduced by calculations relying on the wealth of heat flow and heat production data available there. Physical models of magma ascent and storage favour the formation of magma reservoirs at shallow levels. This suggests that crustal growth proceeds mostly from the top down, with material that gets buried to increasingly large depths. Vertical growth is accompanied by lateral spreading in two different places. Within the crust, magma intrusions are bound to extend in the horizontal direction. Deeper down, lateral variations of Moho depth that develop due to the focussing of magmatic activity get relaxed by lower crustal flow. This review has not dealt with processes at the interface between the growing crust and the mantle, which may well be where dikes get initiated by mechanisms that have so far defied theoretical analyses. Research in this particular area is required to further our understanding of continental crust formation.
DS1989-0936
1989
Mareschal, M.Mareschal, M.Electrical conductivity in the Kapuskasking upliftGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A103. (abstract.)OntarioTectonics, Kapuskasing Lithoprobe
DS1990-0985
1990
Mareschal, M.Mareschal, M.Electrical conductivity: the story of an elusive parameter, and of how it possibly relates to the Kapuskasing Uplift (Lithoprobe, Canada)Exposed cross sections of the Continental Crust, ed. M.H. Salisbury and, pp. 453-468OntarioKapuskasing zone, Tectonics
DS1991-1052
1991
Mareschal, M.Mareschal, M., Kurtz, R.D., Chouteau, M., Chakridi, R.A magnetotelluric survey on Manitoulin Island and Bruce Peninsula along Glimpce seismic line J: black shales mask the Grenville FrontGeophys. Journal of International, Vol. 104, pp. 173-183OntarioGeophysics -seismics, Magnetotelluric
DS1991-1132
1991
Mareschal, M.Mereu, R.F., Percival, J.A., Mareschal, M., Salisbury, M.H.Collaborative special project to identify seismic reflectors in high grade metamorphic rocks of the Kapuskasing UpliftCan. Cont. Drilling Project, August 40pOntarioGeophysics -seismics, Kapuskasing Zone
DS1992-0996
1992
Mareschal, M.Mareschal, M., Fyfe, W.S., Percival, J., Chan, T.Grain boundary graphite in Kapuskasing gneisses and implications for lower-crustal conductivityNature, Vol. 357, No. 6380, June 25, pp. 674-676OntarioRifting, Geophysics -conductivity
DS1993-0791
1993
Mareschal, M.Katsube, T.J., Mareschal, M.Petrophysical model of deep electrical conductors: graphite lining as A source and its disconnection due to upliftJournal of Geophysical Research, Vol. 98, No. B5, May 10, pp. 8019-8030MantleTectonics, Geophysics -electromagnetic conductors
DS1994-1101
1994
Mareschal, M.Mareschal, M., et al.A review of electromagnetic investigations in the Kapuskasing uplift and surrounding regions: key rocks.Canadian Journal of Earth Sciences, Vol. 31, No. 7, July pp. 1042-1051.OntarioGeophysics -electromagnetics, Tectonics -Kapuskasing uplift
DS1995-1167
1995
Mareschal, M.Mareschal, M., Kellett, R.L., Juntz, R.D., Ludden, J.N. Li.Archean cratonic roots, mantle shear zones and deep electrical SOURCE[ NatureNature, Vol. 375, No. 6527, May 11, pp. 134-136.MantleCraton, Geophysics
DS1995-1168
1995
Mareschal, M.Mareschal, M., Kellett, R.L., Kurtz, R.D., Ludden, JiArchean cratonic roots, mantle shear zones and deep electrical anisotropy.Nature, Vol. 375, No. 6527, May 11, pp. 134-136MantleCraton, Geophysics -seismics
DS1995-2129
1995
Mareschal, M.Zhang, P., Chouteau, M., Mareschal, M., Jurtz, R., HubertHigh frequency magnetotelluric investigation of crustal structure in north central Abitibi QuebecGeophy. Journal, Vol. 120, pp. 406-418QuebecLithoprobe - AMT, Abitibi greenstone belt
DS1996-1282
1996
Mareschal, M.Senechal, G., Mareschal, M., Hubert, C., Calvert, et al.Integrated geophysical interpretation of crustal structures in the northern Abitibi belt: seismics, ,Canadian Journal of Earth Sciences, Vol. 33, No. 9, Sept. pp. 1343-1362QuebecGeophysics - seismics, structure, Abitibi belt
DS200612-0867
2006
Mareschall, H.R.Mareschall, H.R., Altherr, R., Rupke, L.Squeezing out the slab - modelling the release of Li, Be and B during progressive high pressure metamorphism.Chemical Geology, in press available,MantleSubduction zone
DS1994-1069
1994
Mareychev, A.M.Lukyanova, L.I., Mareychev, A.M., et al.The first discovery of lamproite magmatism in the southern UralsDoklady Academy of Sciences, Vol. 325, No. 5, pp. 118-123.Russia, UralsMagmatism -lamproite, Lamprophyres
DS202107-1112
2021
Marfin, A.Marfin, A., Radomskaya, T.A., Ivanov, A.V., Belozerova, O.Y.U-Pb dating of apatite, titanite and zircon of the Kingash mafic-ultramafic massif, Kan terrane Siberia: from Rodinia break-up to the reunion of the Siberian craton.Journal of Petrology, Vol. 62, 6, EGAb049Russia, Siberiacratons

Abstract: The initial stage of Rodinia supercontinent break-up occurred at about 750?Ma. It preceded formation of the Irkutsk and Franklin Large Igneous Provinces (LIPs)at 712 ± 2?Ma to 739 ± 8?Ma. These LIPs were emplaced within the formerly connected Laurentian and Siberian cratons. The Kingash massif is located in the Precambrian Kan terrane in direct contact with the Siberian Craton at its southwestern boundary. It has been linked to an important suite of mafic-ultramafic intrusions which border the southern margin of the Siberian craton, and which have been inferred to belong to the Irkutsk LIP. The massif is also significant, because it hosts PGE-Cu-Ni rich mineralization and is the only large deposit in the region. However, despite numerous dating attempts, the age of the massif had not been resolved. A significant difficulty is post-magmatic recrystallization at amphibolite facies that affected the rocks of the massif. In this study we used U-Pb dating of zircon, titanite and apatite from rocks of the Kingash massif and cross-cutting granite and monzonite veins. The oldest igneous zircon grain of the Kingash massif analysed by LA-ICPMS yields an age of c. 750?Ma, taken as a tentative age of magmatism. Dating of multiple grains of metamorphic zircon by CA-ID-TIMS yielded 564.8 ± 2.2?Ma, which is in agreement with LA-ICPMS titanite ages 557 ± 19?Ma, 565 ± 35?Ma and 551 ± 17?Ma. Apatite of two different samples showed ages of 496.4 ± 7.9?Ma and 497.0 ± 1.8?Ma (LA-ICPMS), which are interpreted as the time when the terrane cooled below the closure temperature of apatite. Using our new data we suggest that at the time of the Irkutsk-Franklin LIP event the Kan terrane was a part of Rodinia, then it separated from either Siberia or Laurentia during the break-up of Rodinia and finally collided with Siberia at 560?Ma; the time of regional amphibole facies metamorphism.
DS202107-1103
2021
Marfin, A.E.Ivanov, A.V., Corfu, F., Kamenetsky, V.S., Marfin, A.E., Vladykin, N.V.207Pb-excess in carbonatitic baddeleyite as the result of Pa scavenging from the melt. ( Guli Siberian traps)Geochemical Perspectives Letters, Vol. 18, pp. 11-15. pdfRussia, Siberiacarbonatite

Abstract: For the last two decades, the end of the voluminous phase of eruptions of the Siberian Traps large igneous province has been constrained by a U-Pb date of discordant baddeleyite collected from the Guli carbonatite intrusion with the assumption that the discordance resulted from unsupported 207Pb. In this study we have re-analysed baddeleyite from the same intrusion and found two types of discordance: (1) due to 207Pb-excess, and (2) radiogenic lead loss from high U mineral inclusions. The former implies that baddeleyite is an efficient scavenger of protactinium during crystallisation, leaving the magma depleted in this element. Together with a published high precision U-Pb date of 252.24?±?0.08 Ma for the Arydzhansky Formation, our new date of 250.33?±?0.38 Ma for the Guli carbonatite constrains the total duration of the voluminous eruptions of the Siberian Traps LIP at 1.91?±?0.38 million years. The lower intercept of the (231Pa)/(235U) corrected discordance line yields a date of 129.2?±?65.0 Ma, which points to the widespread Early Cretaceous rifting in East and Central Asia.
DS202109-1474
2020
Marfin, A.E.Ivanov, A.V., Corfu, F., Kamenetsky, V.S., Marfin, A.E., Vladykin, N.V.207 Pb-excess in carbonatitic baddeleyite as the result of Pa scavenging from the melt.Geochemical Perspectives Letters, Vol. 18, pp. 11-15. pdfRussia, Siberiadeposit - Guli

Abstract: For the last two decades, the end of the voluminous phase of eruptions of the Siberian Traps large igneous province has been constrained by a U-Pb date of discordant baddeleyite collected from the Guli carbonatite intrusion with the assumption that the discordance resulted from unsupported 207Pb. In this study we have re-analysed baddeleyite from the same intrusion and found two types of discordance: (1) due to 207Pb-excess, and (2) radiogenic lead loss from high U mineral inclusions. The former implies that baddeleyite is an efficient scavenger of protactinium during crystallisation, leaving the magma depleted in this element. Together with a published high precision U-Pb date of 252.24?±?0.08 Ma for the Arydzhansky Formation, our new date of 250.33?±?0.38 Ma for the Guli carbonatite constrains the total duration of the voluminous eruptions of the Siberian Traps LIP at 1.91?±?0.38 million years. The lower intercept of the (231Pa)/(235U) corrected discordance line yields a date of 129.2?±?65.0 Ma, which points to the widespread Early Cretaceous rifting in East and Central Asia.
DS1991-1053
1991
Marfunin, A.S.Marfunin, A.S.Diamond sources: Russia #1International Gemological Symposium, June 20-24, 1991 Los Angeles, Gems and Gemology, Vol. 27, Spring, Program p. 3RussiaDiamond production-sources
DS1992-0997
1992
Marfunin, A.S.Marfunin, A.S.Diamond sources: Russia #2Gemological Institute of America, Proceedings Volume ed. A. Keller, p. 56. (abstract)RussiaEconomics, Diamond production
DS1995-1260
1995
Marfunin, A.S.Mineeva, R.M., Titkov, S.V., Marfunin, A.S., et al.EPR spectroscopy of Yakutian diamondsProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 389.Russia, YakutiaDiamond morphology, Spectroscopy
DS1996-0548
1996
Marfunin, A.S.Gorshov, A.N., Titkov, S.V., Marfunin, A.S.The first finds of native chromium, nickel and alpha iron in carbonado from the Diamond deposits of Yakutia.Geochemistry International, Vol. 33, No. 1, Jan. 1, pp. 59-63.Russia, YakutiaCarbonado, Native chromium, nickel, iron
DS1998-0942
1998
Marfunin, A.S.Marfunin, A.S.Advanced mineralogySpringer, 490p. approx. $ 200.00GlobalBook - ad, Mineralogy - mantle, ocean, space
DS1999-0444
1999
Marfunin, A.S.Marfunin, A.S., Kononov, O.V., Shelementiev, Y.B.Diamond mineralogy, physics, Gemology and world market: state of the artMoscow University of Geol. Bulletin., Vol. 53, No. 5, pp. 53-66.RussiaDiamond geology - overview
DS200812-0338
2008
Marfunin, A.S.Fang, L., Kononov, O.V., Marfunin, A.S., Taraevich, A.V., Tarasavich, B.N.Development of a technique for IR spectroscopic determination of nitrogen content and aggregation degree in diamond crystals.Moscow University Geology Bulletin, Vol. 63, 4, pp. 281-284.TechnologyDiamond morphology
DS200412-1225
2003
Margerin, L.Margerin,L., Nolet, G.Multiple scattering of high frequency seismic waves in the deep Earth: PKP precursor analysis and inversion for mantle granulariJournal of Geophysical Research, Vol. 108, B11, ESE 9 10.1029/2003 JB002455MantleGeophysics - seismics
DS200612-0868
2006
Margerin, L.Margerin, L.Attenuation, transport and diffusion of scalar waves in textured random media.Tectonophysics, Vol. 416, 1-4, April 5, pp. 229-244.MantleGeophysics - seismics
DS2000-0616
2000
Marhsak, S.Marhsak, S., Karlstrom, K., Timmons, J.M.Inversion of Proterozoic extensional faults: an explanation for the pattern of Laramide and Rockies...Geology, Vol. 28, No.8, Aug. pp. 735-8.United States, CordilleraTectonics, Intracratonic deformation
DS201911-2545
2019
Maria, A.H.Maria, A.H., Denny, F.B., DiPietro, J.A., Howard, K.F., King, M.D.Geochemistry and Sr-Nd isotopic compositions of Permian ultramafic lamprophyres in the Reelfoot Rift- Rough Creek granen, southern Illinois and northwestern Kentucky.Lithos, Vol. 340-341, pp. 191-208.United States, Illinois, Kentuckycarbonatite

Abstract: Permian dikes, sills, and diatremes in southern Illinois and northwestern Kentucky (the Omaha, Wildcat Hills, Cottage Grove, Will Scarlet, Williams, Grant, and Clay Lick intrusions) share similar geochemistry and are classified as ultramafic lamprophyres. Major element compositions are 30-35 wt% SiO2, 6-7% Al2O3, 12-14% FeOt, 16-19% MgO, 3-5% TiO2, 11-16% CaO, 0.1-0.7% Na2O, 1.2-2.7% K2O, and 0.4-1.3% P2O5. The Grant Intrusive Breccia is an exception, with lower SiO2, Al2O3, FeOt, MgO, TiO2, and higher CaO. Typically, these rocks are fine grained, with phlogopite, serpentinized olivine ( Fo88), diopside, perovskite, Fe-Ti-spinel, apatite, and calcite. Blocky and lath-shaped pseudomorphs in some samples probably represent melilite, which would make the rocks alnöites. The Grant and Williams diatremes contain sedimentary and igneous clasts (including amphibole megacrysts) within a carbonate-rich matrix. The Grant exhibits pelletal lapilli and is characterized as a lamprophyre?carbonatite tuffisite. Trace element patterns exhibit enrichment of LREE, strong REE fractionation, and relative depletions of K, Sr, Zr, and Hf, closely matching those of the mela-aillikites of Aillik Bay, Labrador. The Grant Intrusive exhibits even greater REE enrichment and notable peaks at Nb, La, and Ce. Geochemical characteristics, including distributions of 143Nd/144Nd and 87Sr/86Sr, are consistent with near-primary melts from a metasomatized peridotite source containing phlogopite-rich veins. Derivation of the lamprophyres from carbonate-rich parental melts similar to the Grant Intrusive could be achieved by separation of carbonatite. A narrow range of initial 87Sr/86Sr (0.70301-0.70449), and initial ?Nd (3.7-5.1), suggests a uniform mantle source close to Bulk Earth. T-depleted mantle model ages range from 540 to 625 Ma, and might correlate with timing of enrichment of a lithospheric mantle source during the breakup of Rodinia.
DS1991-1054
1991
Mariani, E.Mariani, E., Venturelli, G., Toscani, L., Barbieri, M.The Jumilla lamproites, southeast Spain: late magmatic -hydrothermal activityEuropean Current Research Fluid Inclusions, Firenze, Italy April 10-12, Abstracts, ECROFI XI, p. 191-192GlobalLamproite, Jumilla
DS201412-0198
2014
Mariani, E.Dobson, D.P., Mariani, E.The kinetics of the reaction of majorite plus ferropericlase to ringwoodite: implications for mantle upwellings crossing the 660 km discontinuity.Earth and Planetary Science Letters, Vol. 408, pp. 110-118.MantleRingwoodite
DS1988-0730
1988
Mariani, E.S.Venturelli, G., Mariani, E.S., Foley, S.F., Capedri, S., CrawfordPetrogeneis and conditions of crystallization of SpanishlamproiticrocksCanadian Mineralogist, Vol. 26, No. 1, March pp. 67-80GlobalLamproite
DS1999-0808
1999
Mariano, A.Wright, W.R., Mariano, A., Hagni, R.D.Pyrochlore mineralization and glimmerite formation in the Elder ( Lake LeMoyne) carbonatite complex.The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) 33rd Forum Industrial Minerals Proceedings, Vol. 50, pp. 205-13.Quebec, Ungava, LabradorCarbonatite - mineralogy
DS201702-0249
2016
Mariano, A. Jr.Verplanck, P.L., Mariano, A.N., Mariano, A. Jr.Rare earth element ore geology of carbonatites.Reviews in Economic Geology, Vol. 18, pp. 5-32.GlobalCarbonatite
DS201212-0443
2012
Mariano, A.Jr.Mariano, A.N., Mariano, A.Jr.Rare earth mining and exploration in North America.Elements, Vol. 8, 5, Oct. pp. 369-376.Canada, United StatesEconomics - overview of mode of occurrence, mineralogy, history of exploration
DS201412-0550
2014
Mariano, A.Jr.Mariano, A.N., Mariano, A.Jr.Cathodluminescence as a tool in exploration geology.GAC/MAC short Course, MayTechnologyCathodluminescence
DS201605-0916
2016
Mariano, A.M.Jr.Verplanck, P.L., Mariano, A.N., Mariano, A.M.Jr.Rare earth element ore geology of carbonatites.SEG Reviews in Economic Geology, editors Verplanck, P.L., Hitzman, M.W., No. 18, pp. 5-32.China, United States, CaliforniaBauan Obo, Maoniuping, Dalucao, Mountain Pass
DS1975-0801
1978
Mariano, A.N.Mariano, A.N.The Application of Catholuminescence for Carbonatite Exploration and Characterization.I Symposio International De Carbonatitos, Pocos De Caldas, Brasil, PP. 39-57.GlobalExperimental Studies, Rare Earth Elements (ree), Probe Data
DS1983-0273
1983
Mariano, A.N.Haggerty, S.E., Mariano, A.N.Strontian Loparite and Strontio Chevkinite: Two New Minerals in Rheomorphic Fenites from the Parana Basin Carbonatites, south America.Contributions to Mineralogy and Petrology, Vol. 84, No. 4, PP. 365-381.Brazil, ParaguayRelated Rocks, Mineralogy
DS1985-0413
1985
Mariano, A.N.Mariano, A.N., Druecker, M.D.Alkaline Igneous Rocks and Carbonatites of ParaguayGeological Society of America (GSA), Vol. 17, No. 3, P. 166. (abstract.).South America, ParaguayGeophysics, Lineaments
DS1986-0204
1986
Mariano, A.N.Eby, G.N., Mariano, A.N.Geology and geochronology of carbonatites peripheral to the Parana Brasil-ParaguayGeological Association of Canada (GAC) Annual Meeting, Vol. 11, p. 66, (abstract.)Brazil, Paraguay, South AmericaCarbonatite
DS1986-0525
1986
Mariano, A.N.Mariano, A.N.Nature of economic mineralization in carbonatitesGeological Association of Canada (GAC) Annual Meeting, Vol. 11, p. 99. (abstract.)GlobalCarbonatite, Lanthanides, Rare earth
DS1989-0937
1989
Mariano, A.N.Mariano, A.N.Nature of economic mineralization in carbonatites and related rocksCarbonatites -Genesis and Evolution, Ed. K. Bell Unwin Hyman Publ, pp. 149-California, China, Tanzania, Burundi, Brazil, VenezuelaKenya, Australia, Rare earths, Economics
DS1989-0938
1989
Mariano, A.N.Mariano, A.N.Classification of rare earth elements (REE) in carbonatitesReviews in Mineralogy: Geochemistry and mineralogy of Rare earth, Vol. 21, pp. 330-334California, Malawi, Tanzania, Brazil, Burundi, China, AustraliaCarbonatite, rare earth elements (REE).
DS1989-0939
1989
Mariano, A.N.Mariano, A.N., Francis, C.A.Dalyite from fenites in carbonatite complexes of the Minas Gerais-Goiasbelt, BrasilGeological Society of America (GSA) Annual Meeting Abstracts, Vol. 21, No. 6, p. A46. AbstractBrazilCarbonatite, Mineralogy -Dalyite
DS1989-0940
1989
Mariano, A.N.Mariano, A.N., Roeder, P.L.Wohlerite: chemical composition, cathodoluminescence and environment ofcrystallizationCanadian Mineralogist, Vol. 27, No. 4, December pp. 709-720OntarioPrairie Lake, Alkaline Complex
DS1990-0986
1990
Mariano, A.N.Mariano, A.N., Mitchell, R.H.Mineralogy and geochemistry of perovskite- rich pyroxenitesGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Vancouver 90 Program with Abstracts, Held May 16-18, Vol. 15, p. A83. AbstractBrazil, North America, Greenland, RussiaCarbonatite, Alkaline rocks
DS1991-0751
1991
Mariano, A.N.Hughes, J.M., Cameron, M., Mariano, A.N.Rare earth element ordering and structural variations in natural rare earth bearing apatitesAmerican Mineralogist, Vol. 76, pp. 1165-1173Quebec, New MexicoOka, Carbonatite
DS1991-1055
1991
Mariano, A.N.Mariano, A.N., Marchetto, M.Serra Negra and Salitre-carbonatite alkaline igneous complexFifth International Kimberlite Conferences Field Excursion Guidebook, Servico Geologico do Brasil (CPRM) Special, pp. 75-82BrazilCarbonatite, Alkaline rocks
DS1991-1056
1991
Mariano, A.N.Mariano, A.N., Mitchell, R.H.Mineralogy and geochemistry of perovskite rich pyroxenitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 251-253BrazilCatalao I, Serra Negra, Tapira, glimmerite, Anatase, Rhabdophane
DS1992-0408
1992
Mariano, A.N.Eby, G.N., Mariano, A.N.Geology and geochronology of carbonatites and associated alkaline rocks peripheral to the Parana Basin, Brasil-ParaguayJournal of South American Earth Sciences, Vol. 6, No. 3, October pp. 207-216Brazil, ParaguayCarbonatite, Geochronology
DS1996-1497
1996
Mariano, A.N.Wall, F., Mariano, A.N.Rare earth minerals in carbonatites: a discussion centred on the Kangankunde carbonatite, Malawi.Mineralogical Soc. Series, No. 7, pp. 193-226.MalawiRare earth minerals, Carbonatite, Deposit - Kangankunde
DS1997-0701
1997
Mariano, A.N.Lumpkin, G.R., Leung, S.H.F., Mariano, A.N.Paragenesis and composition of columbite and pyrochlore from the Blue Rivercarbonatite, British Columbia.Geological Association of Canada (GAC) Abstracts, British ColumbiaCarbonatite
DS1997-0702
1997
Mariano, A.N.Lumpkin, G.R., Mariano, A.N., Leung, S.H.F.Ideal defect pyrochlores from the Arax carbonatite complex and laterite Alto Paranaba Province, Brasil.Geological Association of Canada (GAC) Abstracts, POSTER.BrazilCarbonatite, Deposit - Arax
DS1997-0803
1997
Mariano, A.N.Mitchell, R.H., Xiong, J., Mariano, A.N., Fleet, M.E.Rare earth element activated cathodluminescence in apatiteCanadian Mineralogist, Vol. 35, No. 4 Aug. p. 979-998.GlobalCarbonatite, Alkaline rocks
DS1997-1270
1997
Mariano, A.N.Wright, W.R., Mariano, A.N.Petrology and geochemistry of the ultrapotassic rocks from the Sabatini volcanic district, alkaline magma....Geological Society of America (GSA) Abstracts, Vol. 29, No. 4, Apr. p. 79.QuebecCarbonatite
DS1997-1271
1997
Mariano, A.N.Wright, W.R., Mariano, A.N., Hagni, R.D.Geological, petrological, mineralogical ( including rare earth elements (REE) and Nb-Tamineralization) and geochemical examinationGeological Association of Canada (GAC) Abstracts, POSTER.Quebec, Labrador TroughCarbonatite, Deposit - Eldor
DS2001-1215
2001
Mariano, A.N.Wall, F., Zaitsev, A.N., Mariano, A.N.Rare earth pegmatites in carbonatitesJournal of South African Earth Sciences, Vol. 32, No. 1, p. A 35-6.(abs)GlobalCarbonatite, Pegmatites - rare earth elements (REE).
DS2002-0630
2002
Mariano, A.N.Hagni, R.D., Shivdansan, P.A., Mariano, A.N.Cathodluminescence microscopy applications to carbonatite ores: carbonatites and fluorite ores and concentrates at Okorusu, Namibia.18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.151,246.NamibiaCarbonatite
DS2002-1473
2002
Mariano, A.N.Shivdasan, P.A., Hagni, R.D., Mariano, A.N.Character, paragenetic sequence and origin of the carbonatite host rocks for the fluorite deposits at Okorusu, Namibia.11th. Quadrennial Iagod Symposium And Geocongress 2002 Held Windhoek, Abstract p. 40.NamibiaCarbonatite - mineralogy
DS2002-1474
2002
Mariano, A.N.Shivdasan, P.A., Mariano, A.N., Mitchell, R.H.Celsian and slawsonite in the Okorusu complex, Namibia11th. Quadrennial Iagod Symposium And Geocongress 2002 Held Windhoek, Abstract p. 40.NamibiaCarbonatite - mineralogy
DS200712-0680
2006
Mariano, A.N.Mariano, A.N., Schatzlein, D.Rapid in field identification of rare earth elements (REE) using field portable XRF.The Gangue, GAC, MDD, CIM newsletter, No.89, April, pp. 1, 8-11.Canada, Northwest TerritoriesThor Lake area, technology REE
DS201212-0443
2012
Mariano, A.N.Mariano, A.N., Mariano, A.Jr.Rare earth mining and exploration in North America.Elements, Vol. 8, 5, Oct. pp. 369-376.Canada, United StatesEconomics - overview of mode of occurrence, mineralogy, history of exploration
DS201412-0550
2014
Mariano, A.N.Mariano, A.N., Mariano, A.Jr.Cathodluminescence as a tool in exploration geology.GAC/MAC short Course, MayTechnologyCathodluminescence
DS201502-0081
2015
Mariano, A.N.Moore, M., Chakhmouradian, A.R., Mariano, A.N., Sidhu, R.Evolution of rare-earth mineralzation in the Bear Lodge carbonatite, Wyoming: mineralogical and isotopic evidence.Ore Geology Reviews, Vol. 64, pp. 499-521.United States, Wyoming, Colorado PlateauDeposit - Bear Lodge
DS201512-1982
2015
Mariano, A.N.Verplanck, P.L., Farmer, G.L., Mariano, A.N.Nd and Sr isotopic composition of rare earth element mineralized carbonatites.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 65-74.GlobalCarbonatite

Abstract: For nearly 50 years, carbonatites have been the primary sources of niobium and rare earth elements (REEs), particularly the light REEs including La, Ce, Pr, and Nd. In addition, carbonatites may be enriched in other critical elements and have the potential to be future sources. Currently, only fi ve of the more than 500 known carbonatites in the world are being mined for REEs: Bayan Obo (Inner Mongolia, China); Maoniuping (Sichuan, China); Dalucao (or Daluxiang, Sichuan, China); and Mountain Pass (California, USA), and the carbonatite-derived laterite at Mount Weld (Australia). To achieve ore-grade REE enrichment, initial carbonatitic magmas require an adequate endowment of REEs and need to evolve in ways for these elements to concentrate in REE-bearing mineral phases. Radiogenic isotope studies of carbonatites clearly point to a mantle origin, but a wide range in isotopic compositions has led to contrasting views about the specifi c mantle reservoir(s) that sourced carbonatites. In this study we use the neodymium and strontium isotopic compositions of a suite of mineralized carbonatites to establish the nature of the source magmas. We examine samples that span a wide range in age (~23 Ma to 1385 Ma), Nd concentrations (3720 to 32,900 ppm), and Sr concentrations (2290 to 167,900 ppm). Our Nd and Sr isotopic data include multiple samples from Mountain Pass (USA; ?Nd i = -3.1 to -5.4, Sri = 0.70512 to 0.70594), Elk Creek (USA; ~?Nd i = 1.7, Sri = 0.7035), and Maoniuping (China; ?Nd i = -4.1 and -4.2, Sri = 0.70627 and 0.70645), and one sample each from Bear Lodge (USA; ?Nd i = 0.1, Sri = 0.70441), Kangankunde (Malawi; ?Nd i = 3.3, Sri = 0.70310), Adiounedj (Mali; ?Nd i = -0.1, Sri = 0.70558), and Mushgai Khudag (Mongolia; ?Nd i = -1.3, Sri = 0.70636). Isotopic data from two producing carbonatite REE deposits (Mountain Pass and Maoniuping) have broadly similar isotopic compositions (?Nd i = -3.1 to -5.4 and Sri = 0.7051 to 0.7065), and these compositions point to a carbonated source in the lithospheric mantle. Mineralized but unmined carbonatites have higher Nd initial isotopic compositions (?Nd i = -1.3 to 3.3) and a wider range in Sr isotopic compositions (Sri = 0.70310 to 0.70637), but these data are consistent with a lithospheric mantle reservoir.
DS201605-0916
2016
Mariano, A.N.Verplanck, P.L., Mariano, A.N., Mariano, A.M.Jr.Rare earth element ore geology of carbonatites.SEG Reviews in Economic Geology, editors Verplanck, P.L., Hitzman, M.W., No. 18, pp. 5-32.China, United States, CaliforniaBauan Obo, Maoniuping, Dalucao, Mountain Pass
DS201702-0249
2016
Mariano, A.N.Verplanck, P.L., Mariano, A.N., Mariano, A. Jr.Rare earth element ore geology of carbonatites.Reviews in Economic Geology, Vol. 18, pp. 5-32.GlobalCarbonatite
DS1999-0505
1999
Mariano, G.Neves, S.P., Mariano, G.Assessing the tectonic significance of a large scale transcurrent shearzone system: Pernambuco lineamentJournal of Structural Geology, Vol. 21, No. 10, Oct. 1, pp. 1369-84.BrazilTectonics - lineament
DS2000-0706
2000
Mariano, G.Neves, S.P., Mariano, G., Guimares, da Silva Filho, MeloIntralithospheric differentiation and crustal growth: evidence from Bororema province, northeastern BrasilGeology, Vol. 28, No. 6, June pp. 519-22.BrazilAlkaline rocks, Geochemistry, Proterozoic crustal growth
DS200412-1422
2004
Mariano, G.Neves, S.P., Mariano, G.Heat producing elements enriched continental mantle lithosphere and Proterozoic intracontinental orogens: insights from BrasiliaGondwana Research, Vol. 7, 2, pp. 427-436.South America, Brazil, Africa, west AfricaGeothermometry, tectonics
DS200412-1423
2004
Mariano, G.Neves, S.P., Melo, S.C., Moura, C.A.V., Mariano, G., Ragel Da Silva, J.M.Zircon Pb Pb geochronology of the Aruaru area, northeastern Brazil: temporal constraints on the Proterozoic evolution of BorboreInternational Geology Review, Vol. 46, 1, pp. 52-63.South America, BrazilGeochronology
DS1986-0102
1986
Mariano, G. Castelo.Branco, R., Mariano, G. Castelo.Geologic aspects of Brazilian kimberlites.(in Portugese)Rem. Revista Escola de Minas, (in Portugese)., Vol. 39, No. 4, pp. 28-36BrazilBlank
DS1991-1057
1991
Mariano, J.Mariano, J., Hinze, W.J.A geophysical investigation of the midcontinent rift and the associated crustal structure in eastern Lake SuperiorGeological Society of America, Abstract Volume, Vol. 23, No. 3, March p. 26MidcontinentGeophysics, Tectonics -rift
DS1992-0711
1992
Mariano, J.Hinze, W.J., Allen, D.J., Mariano, J.Lithosphere of the Midcontinent Rift region: progress and problemsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 319MidcontinentMidcontinent Rift, Lithosphere
DS1992-0998
1992
Mariano, J.Mariano, J., Hinze, W.J.Magnetic modeling of complexly magnetized bodies with implications to the structure of the midcontinent rift in eastern Lake SuperiorEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 320OntarioMidcontinent Rift, Geophysics -magnetics
DS1994-1102
1994
Mariano, J.Mariano, J., Dumont, R., Ross, G., Teskey, D.Correlations between mantle derived alkaline intrusive rocks and semi-magnetic lineations in southeastern Alberta.Geological Survey of Canada Open Forum January 17-19th. Abstracts only, p. 26, 27.AlbertaGeophysics -magnetics, Alkaline rocks
DS1994-1103
1994
Mariano, J.Mariano, J., Hinze, W.J.Gravity and magnetic models of the Midcontinent Rift in eastern LakeSuperior.Canadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 661-674.Ontario, MichiganGeophysics -gravity, magnetics, Tectonics -Midcontinent rift
DS1994-1104
1994
Mariano, J.Mariano, J., Hinze, W.J.Structural interpretation of Midcontinent Rift in east Lake Superior from seismic reflection, potential fieldCanadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 619-628Ontario, MichiganGeophysics -seismics, Tectonics -Midcontinent rift
DS1994-1105
1994
Mariano, J.Mariano, J., Hinze, W.J.Structural interpret. Midcontinent Rift in eastern Lake Superior from seismic reflection and potential field.Canadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 619-628.Ontario, MichiganGeophysics -seismics, Tectonics -Midcontinent rift
DS1995-0023
1995
Mariano, J.Allen, D.J., Braile, L.W., Hinze, W.J., Mariano, J.The midcontinent rift system United States (US): a major Proterozoic continental riftContinental Rifts: evolution, structure, tectonics, No. 25, pp. 375-408Michigan, Wisconsin, Kansas, Lake Superior regionGeophysics - seismics, gravity, Structure
DS1995-0024
1995
Mariano, J.Allen, D.J., Braile, L.W., Hinze, W.J., Mariano, J.The midcontinent rift system United States (US): a major Proterozoic continental riftContinental Rifts: evolution, structure, tectonics, No. 25, pp. 375-408.Michigan, Wisconsin, Kansas, Lake Superior regionGeophysics - seismics, gravity, Structure
DS1995-0803
1995
Mariano, J.Hinze, W.J., Allen, D.J., Braile, L.W., Mariano, J.The Midcontinent rift system: an overviewBasement Tectonics 10, held Minnesota Aug 92, pp. 3-6.MidcontinentTectonics
DS1995-1169
1995
Mariano, J.Mariano, J., Hinze, W.J.Integrated potential field and seismic reflection studies of Midcontinent rift in eastern Lake Superior.Basement Tectonics 10, held Minnesota Aug 92, pp. 11-14.MidcontinentTectonics, Geophysics -seismics
DS1997-0977
1997
Mariano, J.Ross, G.M., Mariano, J., Dumont, R., Kjarsgaard, B., TeskeyWas Eocene magmatism Wide spread in subsurface southern Alberta? evidence from new aeromagnetic anomaly dataGeological Survey of Canada, Bulletin. No. 500, pp. 235-246.AlbertaMagmatism, Archean Medicine Hat Block
DS1997-0941
1997
Mariappan, N.Radhakrishnan, V., Mariappan, N., Thrivikramji, L.P.A QUICKBASE program to analyse pebble shapesComputers and Geosciences, Vol. 23, No. 3, pp. 325-327.GlobalZingg shape classification, Alluvials, placers, pebbles
DS1982-0396
1982
Marie, A.M.Marie, A.M., Mainprice, D.H., Sobolev, N.V.A Transmission Electron Microscopy Study of Olivine Inclusions in Diamond.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 200, (abstract.).RussiaKimberlite, Udachnaya
DS1859-0009
1742
Marie ElizabethMarie ElizabethCatalogue des DiamantsBruxelles: George Fricx, 24P.GlobalDiamond Occurrence
DS201807-1512
2018
Marien, C.Marien, C., Dukstra, A.H., Wilkins, C.The hydrothermal alteration of carbonatite in the Fen complex, Norway: mineralogy, geochemistry and implications for rare earth element resource formation.Mineralogical Magazine Open access special publication Critical metal mineralogy and ore genesis, Vol. 82 (S1) pp. S115-S131.Europe, Norwaycarbonatite

Abstract: The Fen Complex in Norway consists of a ~583 Ma composite carbonatite-ijolite-pyroxenite diatreme intrusion. Locally, high grades (up to 1.6 wt.% total REE) of rare-earth elements (REE) are found in a hydrothermally altered, hematite-rich carbonatite known as rødbergite. The progressive transformation of primary igneous carbonatite to rødbergite was studied here using scanning electron microscopy and inductively coupled plasma-mass spectrometry trace-element analysis of 23 bulk samples taken along a key geological transect. A primary mineral assemblage of calcite, dolomite, apatite, pyrite, magnetite and columbite with accessory quartz, baryte, pyrochlore, fluorite and REE fluorocarbonates was found to have transformed progressively into a secondary assemblage of dolomite, Fe-dolomite, baryte, Ba-bearing phlogopite, hematite with accessory apatite, calcite, monazite-(Ce) and quartz. Textural evidence is presented for REE fluorocarbonates and apatite breaking down in igneous carbonatite, and monazite-(Ce) precipitating in rødbergite. The importance of micro-veins, interpreted as feeder fractures, containing secondary monazite and allanite, is highlighted. Textural evidence for included relics of primary apatite-rich carbonatite are also presented. These acted as a trap for monazite-(Ce) precipitation, a mechanism predicted by physical-chemical experiments. The transformation of carbonatite to rødbergite is accompanied by a 10-fold increase in REE concentrations. The highest light REE (LREE) concentrations are found in transitional vein-rich rødbergite, whereas the highest heavy REE (HREE) and Th concentrations are found within the rødbergites, suggesting partial decoupling of LREE and HREE due to the lower stability of HREE complexes in the aqueous hydrothermal fluid. The hydrothermal fluid involved in the formation of rødbergite was oxidizing and had probably interacted with country-rock gneisses. An ore deposit model for the REE-rich rødbergites is presented here which will better inform exploration strategies in the complex, and has implications for carbonatite-hosted REE resources around the world.
DS1989-0941
1989
Marillier, F.Marillier, F., Keen, C.E., Stockmal, G.S.Seismic reflection probes the deep structure of theCanadianAppalachiansGeos, Vol. 18, No. 1, Winter pp. 16-20AppalachiaTectonics, Structure
DS1989-0942
1989
Marillier, F.Marillier, F., Keen, C.E., Stockmal, G.S., Quinlan, G., WilliamsCrustal structure and surface zonation of the CanadianAppalachians:implications of deep seismic reflection dataCanadian Journal of Earth Sciences, Vol. 26, No. 2, February pp. 305-321NewfoundlandStructure, Geophysics
DS1990-1419
1990
Marillier, F.Stockmal, G.S., Colman-Sadd, Keen, C.E., Marillier, F., O'BrienDeep seismic structure and plate tectonic evolution of the CanadianAppalachiansTectonics, Vol. 9, No. 1, February pp. 45-62AppalachiaTectonics, Geophysics-seismics
DS1992-0761
1992
Marillier, F.Jackson, H.R., Dickie, K., Marillier, F.A seismic reflection study of northern Baffin Bay: implication for tectonicevolutionCanadian Journal of Earth Sciences, Vol. 29, No. 11, November, pp. 2353-2369GlobalGeophysics -seismics, Tectonics
DS202012-2228
2020
Marimon, R.S.Marimon, R.S., Trouw, R.A.J., Dantas, E.L.Significance of age periodicity in the continental crust record: the Sao Francisco craton and adjacent Neoporterozoic orogens as a case study.Gondwana Research, Vol. 86, pp. 144-163. pdfSouth America, Brazilmagmatism

Abstract: The São Francisco Craton, in Brazil, together with adjacent orogenic systems formed during Gondwana assemblage, are well-suited for the study of crustal growth processes. The region's geological history is marked by a series of complete tectono-metamorphic cycles, from the Archean to late Neoproterozoic, comprising arc-related magmatism followed by continental collisions and ultimately post-tectonic igneous events and rifting. In this contribution, a comprehensive isotopic database was compiled from the literature, composed mainly of high-quality U-Pb magmatic and metamorphic ages (ca. 1000), together with Lu-Hf (ca. 1300) and Sm-Nd (ca. 300) data. Using this database, combined with a tectonic/geochemical synthesized review of the region, it is possible to test which of the available contending models can better explain the apparent periodicity in the formation of the continental crustal. Some interpreted the peaks and troughs in the crustal age record as periods of increased magmatic production, controlled by periodic mantellic events. Another hypothesis is that subduction-related rocks are shielded from tectonic erosion after continental amalgamation, the peaks thus reflecting enhanced preservation potential. The latter hypothesis is favored, as the variability regarding the timing of arc-related peak magmatic production (U-Pb age peaks) from different tectonic provinces around the globe and in the considered regions, coupled to the fact that peak arc-production is always closely followed in time by major continental amalgamations (supercontinent formation), precludes a unified global causation effect, such as mantellic overturns or slab avalanches, and supports the preservation bias hypothesis. Furthermore, the worldwide (including the São Francisco Craton) occurrence of plume-related magmatism is concentrated during the periods of supercontinent break-up (i.e. after major collisions), which better relates to a top-down control on mantle convection and opposes most of the models that advocate for the primary periodicity of magmatic production, which predict enhanced plume activity slightly prior or concomitant to supercontinent formation events.
DS201212-0522
2012
Marin, Y.BNikitina, L.P., Marin, Y.B, Skublov, S.G., Korolev, N.M., Saltykova, A.K., et al.U Pb age and geochemistry of zircon from mantle xenoliths of the Katoka and Kat- 115 kimberlitic pipes ( Republic of Angola).Doklady Earth Sciences, Vol. 445, 1, pp. 840-844.Africa, AngolaDeposit - Katoka (Catoca) Kat-115
DS201412-0474
2014
Marin, Y.B.Korolev, N.M., Marin, Y.B., Nikitina, L.P., Zinchenko, V.N., Chissupa, H.M.High Nb rutile from upper mantle eclogite xenoliths of the diamond bearing kimberlite pipe, Catoca ( Angola).Doklady Earth Sciences, Vol. 454, 1, pp. 50-53.Africa, AngolaDeposit - Catoca
DS201112-0971
2011
Marin, Yu.B.Skublov, S.G., Astafev, B.Yu., Marin, Yu.B., Berezin, A.V., Melnik, A.E., Presnyakov, S.L.New dat a on the age of eclogites from the Belmorian mobile belt at Gridino settlement area.Doklady Earth Sciences, Vol. 439, 2, pp.1163-1170.RussiaEclogite
DS201212-0666
2012
Marin, Yu.B.Skublov, S.G., Nikitina, L.P., Marin, Yu.B., Levskii, L.K., Guseva, N.S.U Pb age and geochemistry of zircons from xenoliths of the V. Grib kimberlitic pipe, Arkhangelsk diamond province.Doklady Earth Sciences, Vol. 444, 1, pp. 595-600.Russia, Archangel, Kola PeninsulaDeposit - Grib
DS201412-0838
2013
Marin, Yu.B.Skublov, S.G., Melnik, A.E., Marin, Yu.B., Berezin, A.V., Bogomolov, E.S., Ishmurzin, F.I.New dat a on the age ( U-Pb, Sm-Nd) of metamorphism and a protolith of eclogite like rocks from the Krasnaya Guba area, Belomorian belt.Doklady Earth Sciences, Vol. 451, 1, pp. 1156-1164.RussiaEclogite
DS201806-1210
2018
Marin, Yu.B.Babushkina, M.S., Ugolkov, V.L., Marin, Yu.B., Nikitina, L.P., Goncharov, A.G.Hydrogen and carbon groups in the structures of rock forming minerals of rocks of the lithospheric mantle: FTIR and STA + QMS data. Lherzolites, peridotitesDoklady Earth Sciences, Vol. 479, 2, pp. 456-459.Russia, Siberiadeposit - Udachnaya

Abstract: Using IR-Fourier spectrometry (FTIR) and simultaneous thermal analysis combined with quadrupole mass spectrometry of thermal decomposition products (STA + QMS), olivines and clinopyroxene from xenolites of spinel and garnet lherzolites contained in kimberlites and alkaline basalts were studied to confirm the occurrence of hydrogen and carbon within the structure of the minerals, as well as to specify the forms of H and C. The presence of hydroxyl ions (OH-) and molecules of crystal hydrate water (H2Ocryst) along with CO2, CH, CH2, and CH3 groups was detected, which remained within the structures of mantle minerals up to 1300°C (by the data of both techniques). The total water (OH-and H2Ocryst) was the prevailing component of the C-O-H system.
DS1975-0332
1976
Mar'in, A.M.Mar'in, A.M.A Find of Melilite-bearing Ultramafic Rocks of the Rudny Altai.Akad. Nauk Ssr Izv, Ser. Geol., Vol. 33, No. 3, PP. 44-47.RussiaBlank
DS2001-0891
2001
MarinceaPascal, M.L., Fonteilles, Verkaeren, Piret, MarinceaThe melilite bearing high temperature skarns of the Apuseni Mountains, Carpathians, Romania.Canadian Mineralogist, Vol. 39, No. 5, Oct. pp. 1405-34.RomaniaMelilite
DS201803-0463
2017
Maringira, G.Maringira, G., Nyamunda, T.Duty versus agency in the security state of Zimbabwe: soldiers deployment in Chiadzwa diamond mining.The Extractive Industries and Society, Vol. 4, pp. 172-179.Africa, Zimbabweartisanal mining

Abstract: The deployment of soldiers’ in diamond mining areas in Zimbabwe is beginning to receive much scholarly attention, partly because scholars researching on such issues are mainly driven by the meta-narratives of ‘artisanal miners’, popularly known as "magweja" in the Zimbabwean context. In many cases soldiers are presented as perpetrators of violence within deployed areas, with magweja and villagers, as victims of military deployment. While this is not untrue, this article explores the ways in which soldiers developed mutual relationships with magweja, friendships and interactions with villagers, including sexual relationships in the communities surrounding the diamond area. However, we assert that these relationships were always implicitly characterised by unequal power dynamics in which the authority of deployed soldiers was ominously present and fear sometimes informed the actions of villagers. Soldiers’ power was always materially represented by the authority vested in them by a powerful demagogic state. It was visibly represented through their combat uniforms, and the gun as part of their daily standing orders, including other soldiering routines such as patrols, and guard duties. We argue that even beyond these circumscribed conditions of relations building, the people behind the combat uniforms had their own agencies that never always resonated with that of the state. Their actions were informed by the chain of command and the consequences wrought by failing to abide by standing orders. In this article, we illuminate those hidden narratives and expose the manner in which the dictatorial state instrumentalises its armed forces despite the disparate personal agencies of those soldiers which are suppressed by the very nature of military service. The paper is based on interviews with soldiers, "magweja" and villagers.
DS1994-1808
1994
Maringolo, V.Ulbrich, M.N.C., Maringolo, V., Vlach, S.R.F.Xenocrysts in mafic dikes from the Fernando de Noronha ArchipelagoInternational Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 36-38.BrazilAlkaline rocks
DS1986-0531
1986
Marinho, M.Mascle, J., Marinho, M., Wannesson, J.The structure of the Guinean continental margin: Implications for the connection between the central and south AtlanticoceansGeologische Rundschau, Vol. 75, No. 1, pp. 57-70GuineaTectonics
DS1988-0443
1988
Marinho, M.Mascle, J., Blarez, E., Marinho, M.The shallow structures of the Guinea and Ivory Coast-Ghana transformmargins: their bearing on the equatorial Atlantic Mesozoic evolutionTectonophysics, Vol. 155, No. 1-4, Dec. 1, pp. 193-210GhanaStructure
DS200812-0206
2008
Marini, J.C.Chauvel, C., Lewin, E., Carpenier, M., Arndt, N.T., Marini, J.C.Role of recycled oceanic basalt and sediment in generating the Hf Nd mantle array.Nature Geoscience, Vol. 1, 1, pp. 64-67.MantleGeochemistry
DS200712-0170
2007
Marini, J-C.Chavel, C., Lewin, E., Carpentier, M., Marini, J-C.Recycled oceanic crust and sediments control the Hf-Nd mantle array.Plates, Plumes, and Paradigms, 1p. abstract p. A163.MantleKimberlite
DS200512-0687
2004
Marinkovic, S.N.Marinkovic, S.N.Diamond synthesized at low pressure.Chemistry and Physics of Carbon, Vol. 29, pp. 71-208. Ingenta 1045668832Experimental petrology
DS1986-0122
1986
Marion, C.Campiglio, C., Marion, C., Vanier, M.Study of an olivine boninite from New Caledonia- petrography and mineralchemistry.(in French)Bulletin. Mineralogie, (in French), Vol. 109, No. 4, pp. 423-440New CaledoniaBlank
DS1991-1916
1991
Marion, P.Yvon, J., Marion, P., Michot, L., Villieras, F., Wagner, F.E.Development of mineralogy applications in mineral processingEur. Journal of Mineral, Vol. 3, No. 4, pp. 667-676GlobalMineral processing, overview
DS2002-1025
2002
Marion, S.McCammon, C.A., Beccero, A.I., Lauterbach, S., Blass, U., Marion, S.Oxygen vacancies in perovskite and related structures: implications for the lower mantle.Materials Research Society Symposium Proceedings, Vol. 718, pp. 109-114. Ingenta 1025440383MantlePerovskite
DS1981-0283
1981
Mariotti, P.A.Mariotti, P.A.Vein Controlled Surf Induced Spheroidal Weathering in Harzburgite Presque Isle Marquette Michigan.Geological Society of America (GSA), Vol. 13, No. 6, MARCH P. 288. (abstract.).United States, Michigan, Great LakesBlank
DS201812-2856
2019
Mariotto, G.Nazzarini, S., Nestola, F., Zanon, V., Bindi, L., Scricciolo, E., Petrelli, M., Zanatta, M., Mariotto, G., Giuli, G.Discovery of moissanite in a peralkaline syenite from the Azores Islands.Lithos, Vol. 324-325, pp. 68-73.Europe, Portugal, Azoresmoissanite

Abstract: Our discovery of moissanite grains in a peralkaline syenite from the Água de Pau Volcano (São Miguel, Azores Islands, Portugal) represents the first report of this mineral in present day oceanic geodynamic settings. Raman spectroscopy and single-crystal X-ray diffraction show the presence of both the 6H and 4H polytypes with the predominance of the first one. The distribution of trace elements is homogeneous, except for Al and V. Azorean moissanite often hosts rounded inclusions of metallic Si and other not yet identified metallic alloys. A process involving a flushing of CH4-H2 ultra-reducing fluids in the alkaline melts might be considered as a possible mechanism leading to the formation of natural SiC, thus calling for strongly reducing conditions that were locally met in the crust-mantle beneath the São Miguel Island.
DS202205-0704
2022
Maritz, L.Maritz, L., Pillay, D., Branch, G.M.The ecology of coastal wetland ponds created by diamond mining in southern Namibia. 1. Physical Conditions.African Journal of Marine Science, Vol. 44, 1, pp. 49-60.Africa, Namibiamining

Abstract: Coastal diamond mining in southern Namibia involves constructing seawalls to hold the sea at bay, and seaward accretion of the shoreline by up to 800 m opens what was previously the surf zone for excavation and extraction of bedrock alluvial diamonds. This has created large coastal wetland ponds of up to 380 000 m2 as the sea overtops the seawalls or seeps into the excavated areas. The ages of these ponds span 1-38 years. We investigated physical conditions in the ponds to determine whether they can function as saline wetlands equivalent to blind estuaries. Water temperatures were 6-10 °C higher than in the sea, as expected of shallow enclosed waterbodies. Dissolved oxygen was 82-137%, peaking at midday owing to photosynthesis, and the ponds were never hypoxic. Correlated with oxygen levels, pH values spanned 7.7-8.3, and always exceeded the pH of seawater. Chlorophyll a concentrations matched or exceeded the levels in seawater, reaching 76 µg l?1. The southern and central ponds had salinities close to those of seawater, but the salinity of northern ponds exceeded 80 after ?15 years, thus limiting their capacity to support wetland communities. Apart from this, these ponds are viable habitat that can support flora and fauna typical of saline wetlands, a habitat that is scarce along this arid coastline.
DS202205-0705
2022
Maritz, L.Maritz, L., Pillay, D., Branch, G.M.The ecology of coastal wetland ponds created by diamond mining in southern Namibia. 2. Saltmarsh vegetation.African Journal of Marine Science, Vol. 44, 1, pp. 61-68.Africa, Namibiamining

Abstract: Coastal diamond mining in southern Namibia involves constructing seawalls to hold the sea at bay, and seaward accretion of the shoreline by up to 800 m opens what was previously the surf zone for excavation and extraction of bedrock alluvial diamonds. This has created large coastal wetland ponds of up to 380 000 m2 as the sea overtops the seawalls or seeps into the excavated areas. The ages of these ponds span 1-38 years. We investigated physical conditions in the ponds to determine whether they can function as saline wetlands equivalent to blind estuaries. Water temperatures were 6-10 °C higher than in the sea, as expected of shallow enclosed waterbodies. Dissolved oxygen was 82-137%, peaking at midday owing to photosynthesis, and the ponds were never hypoxic. Correlated with oxygen levels, pH values spanned 7.7-8.3, and always exceeded the pH of seawater. Chlorophyll a concentrations matched or exceeded the levels in seawater, reaching 76 µg l?1. The southern and central ponds had salinities close to those of seawater, but the salinity of northern ponds exceeded 80 after ?15 years, thus limiting their capacity to support wetland communities. Apart from this, these ponds are viable habitat that can support flora and fauna typical of saline wetlands, a habitat that is scarce along this arid coastline.
DS200512-0806
2002
Mariynov, Yu.A.Okamura, S., Mariynov, Yu.A.Cenozoic volcanism of Far East Russia: the relative importance of subcontinental lithosphere and asthenospheric mantle.Deep Seated Magmatism, magmatism sources and the problem of plumes., pp. 95-101.RussiaMagmatism
DS202106-0940
2021
Marjo, C.Halim, A.Y., Kelloway, S.J., Marjo, C., Regenauer-Lieb. K.A Hylogger-Itrax core-scanner comparison for multi-scale high resolution petrophysical characterization workflow. * not specific to diamondsApplied Chemistry, in press available, 18p. PdfGlobalHylogger

Abstract: Recent advances in core scanning technologies allow for fast and non-destructive chemical and mineral profiling of rock samples for mineral services and oil and gas exploration. The aim of these automatic core scan methods is to obtain valuable information for profiling drill core cuttings with minimum sample preparation at relatively high speed. In the last decade, a core logging system using an automated infrared-based hyperspectral line-profiling system, Hylogger, has progressed to become an effective standard for the Australian mineral exploration industry. Its results are used to rapidly obtain mineralogical information allowing the characterisation of different geological formations in near real-time. The interpretation of Hylogger data can be challenging for certain complex mineral mixtures. Here we solve this issue by augmenting the Hylogger interpretation with elemental analysis using the Itrax core scanner equipped with an X-ray fluorescence (XRF) spectrometer. The Itrax core scanner produces high-resolution elemental data of major, minor and trace elements in one dimension. We analyse and compare the Hylogger and Itrax data, with each dataset independently cross-checked using X-ray diffraction (XRD) and thin-section petrology and propose a workflow harvesting the mutual strengths of each method. The recommended workflow consists of rapid screening using Hylogger and XRF analysis, providing new insights into the mineralogy based on comparative multiscale element-mineral analysis. The workflow is tested on four different types of volcanic rock samples, where infrared spectra of individual minerals overlap. We tested tuffaceous ash, basaltic, dolerite, and basaltic-andesitic rocks. Our study shows that embedding Itrax core scanner data into the workflow provides a solution to the challenges of interpreting Hylogger data in complex mineral samples. The proposed workflow provides a total system for multiscale, high-resolution petrophysical analyses and rock property modelling.
DS1997-0734
1997
Marjoribanks, R.W.Marjoribanks, R.W.Geological methods in mineral exploration and miningChapman and Hall, 120p. $ 140.00 CanGlobalBook - Table of contents, Geological methods, techniques, mapping
DS200712-0076
2007
Mark, G.Betts, P.G., Giles, D., SChaefer, B.F., Mark, G.1600 -1500 Ma hotspot track in eastern Australia: implications for Mesoproterozoic continental reconstruction.Terra Nova, Vol. 19, 6, pp. 496-501.AustraliaHotspots, plumes
DS1992-0999
1992
Mark, K.Mark, K.From geosynclinal to geosynclineEarth Sciences History, Vol. 11, No. 2, pp. 68-69GlobalGeosyncline, Theory
DS202111-1762
2021
Markamdeya, R.Chaurasiya, S.K., Markamdeya, R.Utilization of kimberlite as binder for iron ore pellet making.Transactions Indian Institute of Metallurgy, Vol. 74, 8, pp. 1969-1977. 9p. PdfIndiadeposit - Panna

Abstract: During diamond mining at Panna Mines [India], a huge amount of tailing (Kimberlite) is generated. About 6 Million Tonnes is accumulated and stored near mine site and about 0.9 Million Tonnes of tailings are further being generated each year. Till now, no established method is available for utilization of this material, effective utilization is essential for sustainable diamond mining. The Kimberlite contains about 32% [MgO?+?CaO] and 2% Al2O3, and rest are primarily silica, iron oxide [Fe2O3] and LOI. Initially, attempts were made to utilize Kimberlite as flux in iron ore pellet making; however, during green pellet making, it was observed that strength of pellets improved with higher dosages of Kimberlite. Accordingly, further studies were taken to replace conventional binder bentonite with binder prepared from Kimberlite. The iron ore pellet produced with Kimberlite-based binder have exhibited better physical and metallurgical characteristics than pellets produced with conventional binders (Bentonite).
DS1995-1170
1995
Markarian, D.Markarian, D., Grant, J.A., Elliott, B.E.LogView - microsoft windows borehole log ProgramGeological Survey of Canada, Open File 3055 $ 100.00GlobalComputer, Program -LogView
DS1989-0943
1989
Marker, A.Marker, A., Oliveira, J.J. de.Climatic control of the rare earth element distribution in weathering covers above alkaline rocks. southeast BahiaState/BrasilXiii International Geochemical Exploration Symposium, Rio 89 Brazilian Geochemical, pp. 217-219. AbstractBrazilAlkaline rocks, Geochemistry
DS1990-0987
1990
Marker, A.Marker, A., De Oliveira, J.J.The formation of rare earth element scavenger minerals in weathering products derived from alkaline rocks of southeast-Bahia, BrasilChemical Geology ( Geochem. of the Earth's surface and of min. formation, 2nd., Vol. 84, No. 1-4, July 5, pp. 373-374. AbstractBrazilAlkaline rocks, rare earth elements (REE).
DS1991-1058
1991
Marker, A.Marker, A., Friedrich, G., Carvalho, A., Melfi, A.Control of the distribution of Manganese, Cobalt, Zinc, Zrirconium, Titanium and REEs during the evolution of lateritic covers above ultramafic complexesJournal of Geochemical Exploration, Special Publications Geochemical, Vol. 40, No. 1-3, pp. 361-384Brazil, PhilippinesCarbonatite, Geochemistry -laterites
DS1994-1106
1994
Marker, A.Marker, A., De Oliveira, J.J.Climatic and morphological control of rare earth element distribution inweathering mantles on alkaline rocks.Catena, Special issue Laterization Processes, Vol. 21, No. 2-3, pp. 179-194.BrazilAlkaline rocks, Rare earths, Weathering, Laterization
DS1994-1107
1994
Marker, A.Marker, A., de Oliviera, J.J., Schellmann, W.Lithodependence of partly transported weathering horizons above a migmatite diabase contact in Central Bahia State, BrasilCatena, Laterization and Supergene Ore, Vol. 21, No. 2-3, pp. 215-227BrazilDiabase dike, Laterization
DS200612-0869
2005
Marker, B.R.Marker, B.R., Petterson, M.G., McEvoy, F., Stephenson, M.H.Sustainable minerals operations in the Developing World.Geological Society of London Special Publication, SP 250, 256p. aaprox. 160.00GlobalBook - resources
DS1987-0248
1987
Marker, m A.Germann, A., Marker, m A., Friefrich, G.The alkaline complex of Jacupiranga, Sao Paulo/Brasil;petrology and genetic considerationsSymposium on Latin American Geosciences, Zentralblatt fuer geologie und, Vol. 1987, No. 7-8, pp. 807-818BrazilAlkaline rocks, Carbonatite
DS2002-1642
2002
Marker, M.Van Gool, J.A.M., Connelly, J.N., Marker, M., Mengel, F.C.The Nagssugtoqidian Orogen of West Greenland: tectonic evolution and regional correlations from a West Greenland perspective.Canadian Journal of Earth Science, Vol.39,5, May, pp.665-86.GreenlandTectonics - Orogen, ESCOOT
DS1995-1171
1995
Marker, M.E.Marker, M.E., Holmes, P.J.Lunette dunes in the northeast Cape, South Africa: as geomorphic indicators of palaeoenvironmental change.Catena, Vol. 24, No. 4, Oct. 1, pp. 259-274.South AfricaGeomorphology, Paleoenvironment
DS1988-0361
1988
Markezich, M.A.Knapp, R.W., Markezich, M.A., Wojcik, K.M.Seismic reflection studies at Silver City dome, KansasGeological Society of America (GSA) Abstracts, Vol. 20, p. 104. abstract onlyKansasLamproite, Geophysics- seismics
DS1988-0439
1988
Markezich, M.A.Markezich, M.A.A geophysical study of the Hill's Pond lamproite,Woodson and Wilsoncounties, KansasMsc. Thesis, University Of Kansas, Lawrence, 87pKansasLamproite, Geophysics
DS201808-1785
2018
Markham, M.L.Rose, B.C. ,Huang, D., Zhang, Z-H., Stevenson, P., Tyryshkin, A.M., Sangtawesin, S., Srinivasan, S., Loudin, L., Markham, M.L., Edmonds, A.M., Twitchen, D.J., Lyon, S.A., de Leon, N.P.Observation of an environmentally insensitive solid-state spin defect in diamond.Science , Vol. 361, July 6, p. 60-63.Technologysynthetic

Abstract: Engineering coherent systems is a central goal of quantum science. Color centers in diamond are a promising approach, with the potential to combine the coherence of atoms with the scalability of a solid-state platform. We report a color center that shows insensitivity to environmental decoherence caused by phonons and electric field noise: the neutral charge state of silicon vacancy (SiV0). Through careful materials engineering, we achieved >80% conversion of implanted silicon to SiV0. SiV0 exhibits spin-lattice relaxation times approaching 1 minute and coherence times approaching 1 second. Its optical properties are very favorable, with ~90% of its emission into the zero-phonon line and near -transform-limited optical linewidths. These combined properties make SiV0 a promising defect for quantum network applications.
DS201112-1120
2011
MarklWorgard, L., Trumbell, Keiding, Veksler, Wiedenbeck, Wenzel, MarklF, Cl, and S contents of olivine hosted melt inclusions from picritic dike rocks, Etendeka, NW Namibia.Goldschmidt Conference 2011, abstract p.2177.Africa, NamibiaPicrite
DS1997-0735
1997
Markl, G.Markl, G., Bucher, K.Proterozoic eclogites from the Lofiten Island, northern NorwayLithos, Vol. 42, No. 1-2, Dec. 1, pp. 15-36.NorwayEclogites
DS1998-0611
1998
Markl, G.Henjes-Kunst, F., Markl, G.Charnockitic intrusive rocks and related lamprophyres in central DronningMaud Land, East Antarctica...Journal of African Earth Sciences, Vol. 27, 1A, p. 110. AbstractAntarcticaMagmqatisM., Pan-African Orogeny
DS2003-0876
2003
Markl, G.Markl, G., Abart, R., Vennemann, T., Sommer, H.Mid-crustal metasomatic reaction veins in a spinel peridotiteJournal of Petrology, Vol. 44, 6, pp. 1097-1120.MantleBlank
DS200412-1226
2003
Markl, G.Markl, G., Abart, R., Vennemann, T., Sommer, H.Mid-crustal metasomatic reaction veins in a spinel peridotite.Journal of Petrology, Vol. 44, 6, pp. 1097-1120.MantleMetasomatism
DS200512-0390
2004
Markl, G.Halama, R., Vennnemann, T., Siebel, W., Markl, G.The Gronnedal Ika carbonatite syenite complex, South Greenland: carbonatite formation by liquid immiscibility.Journal of Petrology, Vol. 46, 1-2, pp. 191-217.Europe, GreenlandCarbonatite
DS200712-0402
2007
Markl, G.Halama, R., Joron, J-L., Villemant, B., Markl, G., Treuil, M.Trace element constraints on mantle sources during mid-Proterozoic magmatism: evidence for a link between Gardar and Abitibi mafic rocks.Canadian Journal of Earth Sciences, Vol. 44, 4, pp. 459-478.Canada, Quebec, Europe, GreenlandMagmatism
DS200712-0681
2007
Markl, G.Marks, M.A.W., Rudnick, R.L., McCammon, C., Vennemann, T., Markl, G.Arrested kinetic Li isotope fractionation at the margin of the Ilimaussaq complex: evidence for open system processes during final cooling peralkaline igneous rocksChemical Geology, Vol. 246, 3-4, pp. 207-230.Europe, GreenlandGeochronology
DS200912-0473
2009
Markl, G.Marks, M.A.W., Neukirchen, F., Vennemann, T., Markl, G.Textural, chemical and isotopic effects of late magmatic carbonatitic fluids in the carbonatite syenite Tamazeght complex, High Atlas Mountains, Morocco.Mineralogy and Petrology, Vol. 97, pp. 23-42.Africa, MoroccoCarbonatite
DS201012-0398
2009
Markl, G.Kohler, J., Schonenberger, J., Upton, B., Markl, G.Halogen and trace element chemistry in the Gardar Province, South Greenland: subduction related mantle metasomatism and fluid exsolution from alkalic melts.Lithos, Vol. 113, pp. 731-747.Europe, GreenlandMetasomatism
DS201012-0886
2010
Markl, G.Zaitssev, A.N., Wenzel, T., Markl, G., Spratt, J., Petrov, S.V., Williams, C.T.Sadiman volcano, Crater Highlands, Tanzania: does it really contain melilitites and carbonatites or is it just a phonolite nephelinite volcano?International Mineralogical Association meeting August Budapest, abstract p. 559.Africa, TanzaniaPetrology
DS201112-0266
2011
Markl, G.Derrey, I., Hettmann, K., Thaler, F., Wenzel, T., Marks, M., Markl, G.Sulfur content and speciation in sodalite and its possible use as redox proxy.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologySodalite
DS201112-0433
2011
Markl, G.Hettmann, K., Marks, M., Kressing, K., Zack, T., Wenzel, T., Rehkamper, M., Jacob, D., Markl, G.The geochemistry of thallium and its isotopes in a peralkaline magmatic system.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologyMagmatism
DS201112-0604
2011
Markl, G.Lindhuber, M., Marks, M., Wenzel, T., Markl, G.Igneous layering in peralkaline rocks of the Ilmaussaq intrusion, Greenland.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterEurope, GreenlandAlkalic
DS201112-0645
2011
Markl, G.Marks, M.A.W., Hettmann, K., Schilling, J., Frost, B.R., Markl, G.The mineralogical diversity of alkaline igneous rocks: critical factors for the transition from miaskitic to agpaitic phase assemblages.Journal of Petrology, Vol. 52, 3, pp. 439-455.Alkalic
DS201112-0846
2011
Markl, G.Ratschbacher, B., Pfaff, K., Marks, M., Markl, G.Geochemical trends within the lujavrites of the Ilmaussaq intrusion, SW Greenland.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterEurope, GreenlandAlkalic
DS201112-0924
2011
Markl, G.Schilling, J., Marks, m.A.W., Wenzel, T., Vennenmann, T., Horvth, L., Tarassof, P., Jacob, D.E., Markl, G.The magmatic to hydrothermal evolution of the intrusive Mont Sainte Hilaire Complex: insights into the late stage evolution of peralkaline rocks.Journal of Petrology, Vol. 52, 11. pp. 2147-2185.Canada, QuebecAlkaline rocks, carbonatite
DS201112-0932
2011
Markl, G.Schmidt, P., Smith, D., Markl, G.The Eldor carbonatite complex, Quebec, Canada.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterCanada, QuebecCarbonatite
DS201112-0938
2011
Markl, G.Setzer, F., Worgard, L., Wenzel, T., Markl, G.Element mobilization in the Agate Mountain carbonatite complex, NW Namibia.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.136-137.Africa, NamibiaAgate
DS201112-0939
2011
Markl, G.Setzer, F., Worgard, L., Wenzel, T., Markl, G.Element mobilization in the Agate Mountain carbonatite complex, NW Namibia.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.136-137.Africa, NamibiaNews item - Agate
DS201112-0958
2011
Markl, G.Siidra, O.I., Spratt, J., Demeny, A., Homonnay, Z., Markl, G., Zaitsev, A.N.Cation distribution in the crystal structure of a new amphibole group mineral from the Deeti volcanic cone, northern Tanzania.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterAfrica, TanzaniaAlkalic
DS201112-1151
2011
Markl, G.Zaitsev, A.N., Wenzel, T., Markl, G.Natrocarbonatites at Sadiman and Tinderent volcanoes, East African Rift - myth or reality?Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.161-163.Africa, KenyaCarbonatite
DS201112-1152
2011
Markl, G.Zaitsev, A.N., Wenzel, T., Markl, G.Natrocarbonatites at Sadiman and Tinderent volcanoes, East African Rift - myth or reality?Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.161-163.Africa, KenyaCarbonatite
DS201312-0952
2013
Markl, G.Wang, L., Wenzel, T., Vonder Handt, A., Keller, J., Marks, M.A.W., Markl, G.Compositional variation in apatites from carbonatites and associated silicate rocks: a case study of the Kaiserstuhl complex, Germany.Goldschmidt 2013, 1p. AbstractEurope, GermanyCarbonatite
DS201312-1004
2013
Markl, G.Zaitsev, A.N., Wenzel, T., Vennemann, T., Markl, G.Tinderet volcano, Kenya: an altered natrocarbonatite locality?Mineralogical Magazine, Vol. 77, 3, pp. 213-226.Africa, KenyaCarbonatite
DS201412-0545
2014
Markl, G.Mangler, M.F., Marks, M.A.W., Zaitsev, A.N., Eby, G.N., Markl, G.Halogens (F, Cl and Br) at Oldoinyo Lengai volcano ( Tanzania): effects of magmatic differentiation, silicate, natrocarbonatite melt seperation and surface alteration of natrocarbonatite.Chemical Geology, Vol. 365, pp. 43-53.Africa, TanzaniaCarbonatite
DS201412-0962
2014
Markl, G.Wang, L-X., Marks, M.A.W., Wenzel, T., Vonder Handt, A., Keller, J., Teiber, H., Markl, G.Apatites from the Kaiserstuhl volcanic complex, Germany: new constraints on the relationship between carbonatite and associated silicate rocks.European Journal of Mineralogy, Vol. 26, pp. 397-414.Europe, GermanyCarbonatite
DS201604-0617
2016
Markl, G.Ladenburger, S., Marks, M.A.W., Upton, B., Hill, P., Wenzel, T., Markl, G.Compositional variation of apatite from rift related alkaline igneous rocks of the Gardar Province, South Greenland.American Mineralogist, Vol. 101, pp. 612-626.Europe, GreenlandAlkalic

Abstract: Textural and compositional variations of apatite from four intrusions with different characteristic features of the rift-related alkaline Gardar Province were investigated: dyke rocks that belong to the most primitive rocks of the Province (Isortoq), nepheline-syenites associated with a carbonatite (Grønnedal-Ika), SiO2-saturated and SiO2-oversaturated syenites (Puklen) and nepheline-syenites displaying the transition from miaskitic to agpaitic mineral assemblages (Motzfeldt, Fig.1). Additionally, apatites from these intrusions were compared with other apatites of the Gardar Province. These include apatites from the Older Giant Dyke Complex, the Younger Giant Dyke Complex (both from the Tugtutôq region) and a narsarsukite-bearing trachytic dyke (Igdlutalik), as well as apatites from the Kûngnât, the North Qôroq and the Ilímaussaq intrusive complexes. This results in a complete overview of rift-related magmatites of the Gardar Province, ranging from primitive to highly evolved rocks. Backscattered electron images reveal the presence of various types of apatite textures including (i) growth zonation (concentric and oscillatory) that formed during magmatic differentiation and (ii) overgrowth and secondary textures (rounded cores, patchy zonation and overgrowth rims) due to fluid/melt induced metasomatic overprint and intracrystalline diffusion (Fig.2). Additionally, apatite compositions were analyzed with wavelength-dispersive electron microprobe analyses. During the crystallization history of the different intrusions, as well as within samples (documented by zoning patterns), increasing concentrations are observed for Si, REE, Na and F, whereas Cl shows a decreasing trend. However, for F, Cl and Na these trends are only observed in dyke rocks. Compositional variation of the investigated apatites is mainly due to substitution of Ca and P by variable amounts of Si, Na and REE. This study reveals that variations in the chemical composition of apatite are useful tools to obtain geochemical information about the host magma and its magmatic evolution. Here, Si and REE were found to be reliable petrogenetic indicators, whereas Na, F and Cl are only applicable in fast cooling systems to avoid redistribution of those elements.
DS201707-1326
2017
Markl, G.Giebel, R.J., Gauert, C.D.K., Marks, M.A.W., Costin, G., Markl, G.Multi stage formation of REE minerals in the Palabora carbonatite complex, South Africa.American Mineralogist, Vol. 102, pp. 1218-1233.Africa, South Africacarbonatite - Palabora

Abstract: The 2060 Ma old Palabora Carbonatite Complex (PCC), South Africa, comprises diverse REE mineral assemblages formed during different stages and reflects an outstanding instance to understand the evolution of a carbonatite-related REE mineralization from orthomagmatic to late-magmatic stages and their secondary post-magmatic overprint. The 10 rare earth element minerals monazite, REE-F-carbonates (bastnäsite, parisite, synchysite), ancylite, britholite, cordylite, fergusonite, REE-Ti-betafite, and anzaite are texturally described and related to the evolutionary stages of the PCC. The identification of the latter five REE minerals during this study represents their first described occurrences in the PCC as well as in a carbonatite complex in South Africa. The variable REE mineral assemblages reflect a multi-stage origin: (1) fergusonite and REE-Ti-betafite occur as inclusions in primary magnetite. Bastnäsite is enclosed in primary calcite and dolomite. These three REE minerals are interpreted as orthomagmatic crystallization products. (2) The most common REE minerals are monazite replacing primary apatite, and britholite texturally related to the serpentinization of forsterite or the replacement of forsterite by chondrodite. Textural relationships suggest that these two REE-minerals precipitated from internally derived late-magmatic to hydrothermal fluids. Their presence seems to be locally controlled by favorable chemical conditions (e.g., presence of precursor minerals that contributed the necessary anions and/or cations for their formation). (3) Late-stage (post-magmatic) REE minerals include ancylite and cordylite replacing primary magmatic REE-Sr-carbonates, anzaite associated with the dissolution of ilmenite, and secondary REE-F-carbonates. The formation of these post-magmatic REE minerals depends on the local availability of a fluid, whose composition is at least partly controlled by the dissolution of primary minerals (e.g., REE-fluorocarbonates). This multi-stage REE mineralization reflects the interplay of magmatic differentiation, destabilization of early magmatic minerals during subsequent evolutionary stages of the carbonatitic system, and late-stage fluid-induced remobilization and re-/precipitation of precursor REE minerals. Based on our findings, the Palabora Carbonatite Complex experienced at least two successive stages of intense fluid–rock interaction.
DS201811-2617
2018
Markl, G.Walter, B.F., Parsapoor, A., Braunger, S., Marks, M.A.W., Wenzel, T., Martin, M., Markl, G.Pyrochlore as a monitor for magmatic and hydrothermal processes in carbonatites from the Kaiserstuhl volcanic complex ( SW Germany).Chemical Geology, Vol. 498, pp. 1-16.Europe, Germanycarbonatite

Abstract: Pyrochlore from the Kaiserstuhl volcanic complex (SW Germany) shows textural and compositional differences between various coarse-grained calcite-carbonatite bodies (Badberg, Degenmatt, Haselschacher Buck, Orberg) and extrusive carbonatites (Henkenberg, Kirchberg). Oscillatory-zoned F-rich pyrochlore with up to 69?wt% Nb2O5 is common in all coarse-grained calcite-carbonatite bodies and probably formed during magmatic conditions. However, only in some of the samples from the Badberg, partly resorbed U- and Ta-enriched pyrochlore cores with up to 22?wt% UO2 and 9?wt% Ta2O5 have been identified, which are interpreted as being inherited from underlying nosean syenites. Pyrochlore data from a drill core penetrating the Badberg indicate increasing contents of REE, U, and Ta with depth, while Nb, F and Na contents decrease. This may reflect the combined effects of fractional crystallization and assimilation (AFC) or indicates a multi-stage emplacement of the carbonatitic magma. Patchy-zoned ceriopyrochlore and REE- and Th-enriched pyrochlore with up to 19?wt% total REE2O3 and 6.5?wt% ThO2 is largely restricted to samples from the Orberg and probably formed during hydrothermal conditions. This can be related to the relatively evolved character of the Orberg carbonatites, based on their relatively high whole-rock Nb/Ta and Zr/Hf mass ratios. This study demonstrates that the textural and compositional variation of pyrochlore in carbonatites is a powerful tool to distinguish magmatic, hydrothermal and weathering processes in carbonatitic systems.
DS201812-2810
2019
Markl, G.Giebel, R.J., Marks, M.A.W., Gauert, C.D.K., Markl, G.A model for the formation of carbonatite-phoscorite assemblages based on the compositional variations of mica and apatite from the Palabora carbonatite complex, South Africa.Lithos, Vol. 324-325, pp. 89-104.Africa, South Africadeposit - Palabora

Abstract: A detailed electron microprobe study has been carried out on the compositional variations of mica and apatite from carbonatites, phoscorites and associated pyroxenites (and fenites) of the Loolekop deposit, Palabora Carbonatite Complex (South Africa). Mica in pyroxenites and fenites is Mg-rich biotite, whilst micas in carbonatites and phoscorites are compositionally diverse including phlogopite, Ba-rich phlogopite (up to 30% kinoshitalite component), IVAl-rich phlogopite (up to 30% eastonite component) and tetraferriphlogopite. The various types of phlogopites are interpreted as orthomagmatic phases, whereas tetraferriphlogopite precipitation was a late-magmatic to hydrothermal process that additionally introduced REE into the system. Orthomagmatic apatite is generally REE- and Sr-poor fluorapatite and does not show large compositional differences between rock types. Apatite associated with the late-stage tetraferriphlogopite mineralization reaches higher levels of REE (up to 4.9?wt%), Si (up to 1.5?wt% SiO2), Sr (up to 2.6?wt% SrO) and Na (up to 1.0?wt% Na2O). The compositional variation of micas and apatites, which is affiliated with distinct rock types, reflects the multi-stage evolution of the Loolekop deposit and provides detailed insight into the relationships of the carbonatite-phoscorite assemblage. The obtained data support the separation of phoscorite and carbonatite by immiscibility from a common parental magma, which may happen due to a decrease of temperature and/or pressure during the ascent of the magma. This results in a density contrast between the carbonatitic and phoscoritic components that will lead to descending phoscorite accumulations at the outer zones of the magma channel and a jet-like ascent (further promoted by its extremely low viscosity) of the carbonatite magma. The genetic model deduced here explains the peculiar association of carbonatites, phoscorites and silicate rocks in many alkaline complexes worldwide.
DS201902-0273
2019
Markl, G.Giebel, R.J., Marks, M.A.W., Gauert, C.K., Markl, G.A model for the formation of carbonatite-phoscorite assemblages based on the compositonal variations of mica and apatite from the Palabora carbonatite complex, South AfricaLithos, Vol. 324, pp. 68-73.Europe, Azoresdeposit - Palabora

Abstract: A detailed electron microprobe study has been carried out on the compositional variations of mica and apatite from carbonatites, phoscorites and associated pyroxenites (and fenites) of the Loolekop deposit, Palabora Carbonatite Complex (South Africa). Mica in pyroxenites and fenites is Mg-rich biotite, whilst micas in carbonatites and phoscorites are compositionally diverse including phlogopite, Ba-rich phlogopite (up to 30% kinoshitalite component), IVAl-rich phlogopite (up to 30% eastonite component) and tetraferriphlogopite. The various types of phlogopites are interpreted as orthomagmatic phases, whereas tetraferriphlogopite precipitation was a late-magmatic to hydrothermal process that additionally introduced REE into the system. Orthomagmatic apatite is generally REE- and Sr-poor fluorapatite and does not show large compositional differences between rock types. Apatite associated with the late-stage tetraferriphlogopite mineralization reaches higher levels of REE (up to 4.9?wt%), Si (up to 1.5?wt% SiO2), Sr (up to 2.6?wt% SrO) and Na (up to 1.0?wt% Na2O). The compositional variation of micas and apatites, which is affiliated with distinct rock types, reflects the multi-stage evolution of the Loolekop deposit and provides detailed insight into the relationships of the carbonatite-phoscorite assemblage. The obtained data support the separation of phoscorite and carbonatite by immiscibility from a common parental magma, which may happen due to a decrease of temperature and/or pressure during the ascent of the magma. This results in a density contrast between the carbonatitic and phoscoritic components that will lead to descending phoscorite accumulations at the outer zones of the magma channel and a jet-like ascent (further promoted by its extremely low viscosity) of the carbonatite magma. The genetic model deduced here explains the peculiar association of carbonatites, phoscorites and silicate rocks in many alkaline complexes worldwide.
DS201909-2024
2019
Markl, G.Braunger, S., Marks, M.A.W., Wenzel, T., Chmyz, L., Azzone, R.G., Markl, G.Carbonatite-alkaline silica rock complexes reflect highly oxidized conditions in their Upper Mantle source.Goldschmidt2019, 1p. AbstractMantlecarbonatite

Abstract: Alkaline complexes consist of variable mantle-derived silicate rocks, ranging from primitive alkali basalts, melilitites, nephelinites and basanites towards tephrites and more evolved phonolites, respectively their plutonic equivalents. This lithological variance is also expressed by a wide range of redox conditions that vary by several log units around the synthetic fayalite-magnetite-quartz (FMQ) buffer. However, only some of these complexes are characterized by the occurrence of carbonatites which must be related to specific formation conditions. Based on textural, mineralogical and geochemical observations, we calculated the redox conditions of carbonatites and associated silicate rocks for seven alkaline complexes (Kaiserstuhl, Sokli, Kovdor, Palabora, Magnet Cove, Oka, Jacupiranga) which are considered to represent typical carbonatite-alkaline silicate rock associations. In combination with a comprehensive literature review, we demonstrate that carbonatite-bearing alkaline complexes formed under highly oxidized conditions and hence, belong to the most oxidized alkaline rocks at all. This is consistent with the prerequisite of a carbonated mantle as the source region for carbonatite complexes, which requires redox conditions distinctively above that for mean lithospheric or asthenospheric mantle. Carbonatitemetasomatized peridotites also show high redox conditions and might not only reflect an interaction between peridotite and carbonatitic melts/fluids, but at least partly represent the carbonated mantle source for crustally emplaced carbonatite complexes. We therefore suggest that the oxidation state of carbonatites and associated silicate rocks provides direct information about an extraordinary oxidized parental mantle source.
DS201909-2041
2019
Markl, G.Giebel, R.J., Marks, M.A.W., Gauert, C.D.K., Markl, G.A model for the formation of carbonatite-phoscorite assemblages.Goldschmidt2019, 1p. AbstractGlobalcarbonatite

Abstract: A detailed electron microprobe study has been carried out on the compositional variations of mica and apatite from carbonatites, phoscorites and associated pyroxenites (and fenites) of the Loolekop deposit, Palabora Carbonatite Complex (South Africa). Mica in pyroxenites and fenites is Mg-rich biotite, whilst micas in carbonatites and phoscorites are compositionally diverse including phlogopite, Ba-rich phlogopite (up to 30% kinoshitalite component), IVAl-rich phlogopite (up to 30% eastonite component) and tetraferriphlogopite. The various types of phlogopites are interpreted as orthomagmatic phases, whereas tetraferriphlogopite precipitation was a late-magmatic to hydrothermal process that additionally introduced REE into the system. Orthomagmatic apatite is generally REE- and Sr-poor fluorapatite and does not show large compositional differences between rock types. Apatite associated with the late-stage tetraferriphlogopite mineralization reaches higher levels of REE (up to 4.9?wt%), Si (up to 1.5?wt% SiO2), Sr (up to 2.6?wt% SrO) and Na (up to 1.0?wt% Na2O). The compositional variation of micas and apatites, which is affiliated with distinct rock types, reflects the multi-stage evolution of the Loolekop deposit and provides detailed insight into the relationships of the carbonatite-phoscorite assemblage. The obtained data support the separation of phoscorite and carbonatite by immiscibility from a common parental magma, which may happen due to a decrease of temperature and/or pressure during the ascent of the magma. This results in a density contrast between the carbonatitic and phoscoritic components that will lead to descending phoscorite accumulations at the outer zones of the magma channel and a jet-like ascent (further promoted by its extremely low viscosity) of the carbonatite magma. The genetic model deduced here explains the peculiar association of carbonatites, phoscorites and silicate rocks in many alkaline complexes worldwide.
DS201909-2050
2019
Markl, G.Hutchison, W., Baiel, R., Finch, A., Marks, M., Markl, G., Boyce, A., Stueken, E., Friis, H., Borst, A., Horsburgh, N.Sulphur isotopes of alkaline igneous suites: new insights into magmatic fluid evolution and crustal recycling.Goldschmidt2019, 1p. AbstractGlobalalkaline rocks
DS201909-2061
2019
Markl, G.Marks, M.A.W., Giebel, R.J., Walter, B.F., Braunger, S., Wenzel, T., Markl, G.Evidence for wall-rock assimilation in carbonatites from the Kaiserstuhl (German).Goldschmidt2019, 1p. AbstractEurope, Germanydeposit - Kaiserstuhl

Abstract: Contamination of carbonatites with crustal or cogenetic intrusive rocks is generally not considered to play an important role during carbonatite magmatism, because carbonatitic melts have low densities and viscosities, enabling them to rapidly ascend. Potential contamination by silicate rocks in carbonatites cannot easily be detected by means of radiogenic isotope data (such as Sr, Nd and Pb isotope data) as carbonatites often show high concentrations of these elements and their isotope systems are thereby “buffered” against contamination with silicate rocks. Textural, mineralogical and geochemical observations in carbonatites from the Kaiserstuhl (Germany) provide evidence for the interaction of carbonatitic magma with previously emplaced nosean syenites. This caused replacement of alkali feldspar by haüyne and recrystallization of garnet and clinopyroxene in the xenoliths, which released larger amounts of K, Al, Si and Fe. As a result, blackwall-like mica seams around the xenoliths formed and and compositionally distinct mica and clinopyroxene crystallized in the surrounding carbonatite. Moreover, the local increase of silica activity during contamination enabled strong REE enrichment in apatite via a coupled substitution involving Si, which demonstrates the potential influence of Si contamination on REE mineralization in carbonatites. We further suggest that the presence and composition of clinopyroxene and mica in carbonatites may be useful indicators for contamination processes during their emplacement. Mass-balance calculations based on experimental constraints for the solubility of Al and Si in carbonatitic magmas suggest that only minor amounts of mica can form from carbonatitic melt. Therefore, larger amounts of mica and mica-dominated lithologies (glimmerites) as observed in many carbonatite complexes suggest that some Si and Al in carbonatites may be sourced from surrounding host rocks. We hypothesize that assimilation and contamination processes in carbonatites may be the rule rather than an exception.
DS201909-2104
2019
Markl, G.Walter, B.F., Steele-MacInnis, M., Giebel, R.J., Marks, M.A.W., Markl, G.Fluids exsolved from the Kaiserstuhl carbonatite, SW Germany: brine generation by boiling.Goldschmidt2019, 1p. AbstractEurope, Germanydeposit - Kaiserstuhl

Abstract: Studies on fluid inclusions in carbonatitic rocks are essential to understand the physicochemical processes involved in carbonatite-related hydrothermal ore mineralization. Although little is known about the composition of carbonatite-derived fluids. We investigated fluid inclusions in the Kaiserstuhl carbonatites, SW Germany [1,2] and identified four different types typically known from carbonatitic systems worldwide [3]: (I): Vapor-poor H2O-NaCl fluids with <50 wt.% salinity. (II): Vapor-rich H2O-NaCl-CO2 fluids with <5 wt.% salinity. (III): Multi-component fluids with high salinity and CO2. (IV): Multi-component fluids with high salinity, no CO2. Homogenization temperatures (156 to 530°C) of all fluid types generally show a wide range [this study, 2]. Primary type I fluid inclusions occur in early magmatic olivine/monticellite, as well as paragenetically later apatites and calcites [2]. This indicates a ubiquitous existence of a saline brine, which does not reach saturation with respect to halite, during early to late crystallization stages. Liquidus surface modelling based quantifications for fluid type III suggest that carbonatite melts predomonantly exsolve Na-K-sulfate-carbonate/bicarbonate-chloride brines (type III or IV, respectively). Such fluid inclusions, with type III (CO2-free) on one side and type IV (and II, both CO2-rich) on the other side, may represent immiscible fluids that were trapped after segregation by boiling from a parental highly saline brine (type I). Fluid boiling, in turn, is probably triggered by a rapid pressure release during “pneumatic hammer-like,” discontinuous melt ascent.
DS202002-0168
2020
Markl, G.Braunger, S., Marks, M.A.W., Wenzel, T., Chmyz, L., Azzone, R.G., Markl, G.Do carbonatites and alkaline rocks reflect variable redox conditions in their upper mantle source? ( metasomatism)Earth and Planetary Science Letters, Vol. 533, 11p. PdfMantlecarbonatite

Abstract: A detailed investigation on seven carbonatites and associated alkaline rock complexes (Kaiserstuhl, Sokli, Kovdor, Palabora, Oka, Magnet Cove, Jacupiranga), together with a world-wide comparison between carbonatites, alkaline silicate rocks and mantle xenoliths, implies peculiar redox conditions for carbonatite-bearing alkaline complexes: Carbonatites and associated alkaline rocks in continental settings crystallize from relatively oxidized magmas, on average 1.4 log units () and 1.3 log units () above the synthetic fayalite-magnetite-quartz (FMQ) buffer. In contrast, alkaline rocks in continental settings that lack associated carbonatites reveal rather reduced conditions (mean ; ). The calculated redox conditions for carbonatites and associated silicate rocks demonstrate that these crystallize from relatively oxidized mantle-derived melts compared to the general range found for alkaline rocks in continental settings.
DS202006-0955
2020
Markl, G.Walter, B.F., Steele-MacInnis, M., Giebel, R.J., Marks, M.A.W., Markl, G.Complex carbonatite-sulfate brines in fluid inclusions from carbonatites: estimating compositions in the system H2O-Na-K-CO3-SO4-Cl. KaiserstuhlGeochimica et Cosmochimica Acta, Vol. 277, pp. 224-242. pdfEurope, Germanycarbonatite

Abstract: Studies of fluid inclusions in carbonatitic rocks are essential for understanding physicochemical processes involved in carbonatite-related hydrothermal ore mineralization and fenitization. However, the composition of many carbonatite-derived fluids is challenging to quantify, which hampers their detailed interpretation. Here, we present a systematic study of microthermometry of fluid inclusions found in carbonatites from the Kaiserstuhl (SW Germany), and a simple numerical model to estimate the compositions of such fluids, which are typical of numerous carbonatites worldwide. Four types of fluid inclusions have been identified in the Kaiserstuhl carbonatites: (I) vapor-poor H2O-NaCl fluids with <50?wt.% salinity; (II) vapor-rich H2O-NaCl-CO2 fluids with <5?wt.% salinity; (III) multi-component fluids with high salinity and high CO2 contents; and (IV) multi-component fluids with high salinity but little to no CO2. At present, it is only possible to quantify fluid compositions for types I and II. For the complex types III and IV, we conducted predictive modeling of the liquidus surface based on the Margules equations. The results suggest that carbonatite melts predominantly exsolve Na-K-sulfate-carbonate/bicarbonate-chloride brines (types III or IV). Such fluid inclusions may represent immiscible fluids that were trapped after segregation by boiling from a parental highly saline brine (type I). Fluid boiling, in turn, was probably triggered by a rapid pressure release during melt ascent. The present model enables quantification of fluid compositions associated with carbonatitic magmatism.
DS202007-1145
2020
Markl, G.Hecker, J.G., Marks, M.A.W., Wenzel, T., Markl, G.Halogens in amphibole and mica from mantle xenoliths: implications for the halogen distribution and halogen budget of the metasomatized continental lithosphere.American Mineralogist, Vol. 105, pp. 781-794.Mantlemetasomatism

Abstract: This study reports halogen contents (F and Cl) of amphibole and phlogopite derived from mantle xenoliths and one peridotite massif, for amphibole and phlogopite megacrysts and ultramafic magmatic cumulates (hornblendites) found in alkaline volcanic rocks from 12 localities in Europe and Africa. Amphibole and phlogopite contain more F than Cl with F/Cl ratios reaching about 160 in phlogopites and 50 in amphiboles. Phlogopites are higher in F (median of 3400 ?g/g) than amphibole (median of 1000 ?g/g), while median Cl contents are higher in amphibole (290 ?g/g) compared to phlogopite (180 ?g/g). The Cl contents and the F/Cl ratios in amphibole and phlogopite from mantle xenoliths exhibit large differences between samples of the same region, recording very large variations of halogen contents in the continental lithosphere. We suggest that the halogen content in such samples largely depends on the initial composition of percolating melts and fluids in the continental lithosphere. During reaction of these agents with peridotitic wall-rocks, Cl is preferentially retained in the fluid as it is much more incompatible compared to water and F. This desiccation effect continuously increases salinity (Cl content) and decreases the F/Cl ratio in the agent with time, causing variable Cl contents and F/Cl ratios in amphibole and phlogopite at a specific locality. Subsequent partial melting processes may then sequester and re-distribute, especially Cl among amphibole, phlogopite and melts/fluids as a result of its strong incompatibility, whereas F is much less affected as it behaves slightly compatible. The impact of even small amounts of amphibole and mica on the total halogen budget in the continental lithosphere is significant and both minerals can effectively contribute to the high halogen contents typical of alkaline melts.
DS202007-1184
2020
Markl, G.Walter, B.F., Steele-MacInnis, M., Gielbel, R.J., Marks, M.A.W., Markl, G.Complex carbonatite-sulfate brines in fluid inclusions from carbonatites: estimating compositions in the system H2O-Na-K-CO3-SO4-ClGeochimica et Cosmochimica Acta, Vol. 277, pp. 224-242. pdfEurope, Germanydeposit - Kaiserstuhl

Abstract: Studies of fluid inclusions in carbonatitic rocks are essential for understanding physicochemical processes involved in carbonatite-related hydrothermal ore mineralization and fenitization. However, the composition of many carbonatite-derived fluids is challenging to quantify, which hampers their detailed interpretation. Here, we present a systematic study of microthermometry of fluid inclusions found in carbonatites from the Kaiserstuhl (SW Germany), and a simple numerical model to estimate the compositions of such fluids, which are typical of numerous carbonatites worldwide. Four types of fluid inclusions have been identified in the Kaiserstuhl carbonatites: (I) vapor-poor H2O-NaCl fluids with <50?wt.% salinity; (II) vapor-rich H2O-NaCl-CO2 fluids with <5?wt.% salinity; (III) multi-component fluids with high salinity and high CO2 contents; and (IV) multi-component fluids with high salinity but little to no CO2. At present, it is only possible to quantify fluid compositions for types I and II. For the complex types III and IV, we conducted predictive modeling of the liquidus surface based on the Margules equations. The results suggest that carbonatite melts predominantly exsolve Na-K-sulfate-carbonate/bicarbonate-chloride brines (types III or IV). Such fluid inclusions may represent immiscible fluids that were trapped after segregation by boiling from a parental highly saline brine (type I). Fluid boiling, in turn, was probably triggered by a rapid pressure release during melt ascent. The present model enables quantification of fluid compositions associated with carbonatitic magmatism.
DS202109-1494
2021
Markl, G.Walter, B.F., Giebel, R.J., Steele-MacInnis, M., Marks, M.A., Kolb, J., Markl, G.Fluids associated with carbonatitic magmatism: a critical review and implications for carbonatite magma ascent.Earth Science Reviews , Vol. 215, 103509, 27p. PdfMantlemagmatism

Abstract: Carbonatites are formed from volatile-rich melts, commonly associated with a characteristic hydrothermal footprint. However, studies of their fluid inclusions are relatively scarce and heterogeneous in terms of detail and completeness of the data presented. Here, we review and discuss comprehensively the results of previous studies and derive a general model for the formation and properties of fluids associated with carbonatitic magmatism. Worldwide, four types of fluid inclusion occur in carbonatites: (type I/HS) vapour-poor H2O-NaCl fluids with up to 50 wt% salinity; (type II/HC) vapour-rich H2O-NaCl-CO2 fluids with <5 wt% salinity; (type III/DS) multi-component fluids with high salinity and without CO2; and (type IV/CDS) multi-component fluids with high salinity and high CO2. This global dataset suggests continuous fluid release from deep to shallow-level intrusions. Modelling of the liquidus surface indicates that carbonatite magmas generally exsolve a saline brine (type I/HS). This brine separates/evolves into a Na-K-sulfate-carbonate/bicarbonate-chloride brine with or without CO2 (types III/DS and IV/CDS), trapped together with low salinity CO2-rich fluids produced by immiscibility. Fluid immiscibility is related to rapid pressure release during fast, forceful and discontinuous magma ascent, which we envisage as a "pneumatic jackhammer" model for carbonatite ascent and emplacement. In this model, cyclic and progressive fluid flux via pressure build-up and subsequent catastrophic pressure release results in a self-sustaining crustal ascent of the buoyant, low-viscosity magma. This process allows for rapid and efficient magma ascent, in particular above the brittle-ductile transition zone, where pressures that prevailed during apatite crystallization have been estimated in numerous complexes. Moreover, this model provides an explanation for the apparent absence of shallow carbonatite magma chambers (in a classical sense) and identifies fenitization as a phenomenon induced by both fluids released during magma ascent and residual fluids.
DS1995-1896
1995
Markley, M.Teyssier, C., Tikoff, B., Markley, M.Oblique plate motion and continental tectonicsGeology, Vol. 23, No. 5, May pp. 447-450GlobalStructure, Tectonics
DS200512-0340
2004
Markley, M.Giorgis, S., Markley, M., Tikoff, B.Vertical axis rotation of rigid crustal blocks driven by mantle flow.Geological Society of London Special Paper, No. 226, pp. 83-100.MantleTectonics
DS200812-0714
2008
Markner-Jager, B.Markner-Jager, B.Technical english for geosciences. A textbook/workbook.Springer, 78p. $ 50.00GlobalBook - terminology/english/geosciences
DS1984-0481
1984
Marko, K.A.Marko, K.A.Takomkane, an Unusual Basanite in Eastern British ColumbiaBsc. Thesis, Brock University of St. Catherines Ontario, 32pBritish ColumbiaBasanite
DS201212-0265
2012
Marko, L.Grutter, H.S., Gerdes, A., Marko, L., Heaman, L.M.U-Pb geochronology of perovskite and zircon from the Chigicherla kimberlites, Anatapur district, India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Chigicherla
DS1987-0587
1987
Markov, A.S.Podvysotskiy, V.T., Markov, A.S.Ilmenite and titanomagnetite in rocks of the Traprock association in the Malaya Botuobuya and the Alakit-Markha kimberlite fields, YakutiaDoklady Academy of Science USSR, Earth Science Section, Vol. 297, No. 6, Nov-Dec., pp. 144-148RussiaIlmenites, Titanomagnetite
DS200412-1874
2004
Markova, M.E.Soloveva, L.V., Gornova, M.A., Markova, M.E., Lozhkin, V.I.Geochemical identification of granulites in xenoliths from Yakutian kimberlites.Geochemistry International, Vol. 42, 3, pp. 220-235.Russia, YakutiaGeochemistry
DS201903-0530
2018
Markovets, V.Markovets, V.Diamond deposits exploration, scientific and research report.7th Symposio Brasleiro de geologia do diamante, 68 ppts. AvailableSouth America, Brazildiamond geology
DS200812-0589
2008
Markovic, G.Kopylova, M.G., Nowell, G.M., Pearson, D.G., Markovic, G.Crystallization of megacrysts from kimberlites: geochemical evidence from high Cr megacrysts in the Jericho kimberlite.9IKC.com, 3p. extended abstractCanada, NunavutDeposit - Jericho
DS200912-0405
2009
Markovic, G.Kopylova, M.G., Nowell, G.M., Pearson, D.G., Markovic, G.Crystallization of megacrysts from protokimberlitic fluids: geochemical evidence from high - Cr megacrysts in the Jericho kimberlite.Lithos, In press - available 51p.Canada, NunavutDeposit - Jericho
DS201112-0643
2007
Markovic, G.Markovic, G.The age and origin of megacrysts in the Jericho kimberlite, Nunavut Canada.University of British Columbia, Msc. thesis, 100p.Canada, NunavutThesis - note availability based on request via author
DS1981-0088
1981
Markovskiy, A.A.Bogdasarov, E.A., Landa, E.A., Markovskiy, A.A.Chemical Composition and Crystallization Conditions of Chrome Spinels of Volcanic Ultramafics and Other Rocks of the Mafic Ultramafic Series.International Geology Review, Vol. 23, No. 9, PP. 931-RussiaKimberlite, Spinels, Mineralogy
DS1970-0345
1971
Markovskiy, B.A.Markovskiy, B.A., Rotman, V.K.Geosynclinal Meymechite of KamchatkaDoklady Academy of Science USSR, Earth Science Section., Vol. 196, No. 1-6, PP. 158-161.RussiaKimberlite
DS1983-0383
1983
Markovskiy, B.A.Landa, E.A., Lyapunov, S.M., Markovskiy, B.A.Characteristics of rare earth distribution in volcanicultrabasites.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 272, No. 2, pp. 462-464RussiaKamchatka Pen., Anabar Shield, Meymechite, Picrite, Rare Earth
DS201811-2553
2018
Markovsky, B.A.Badredinov, Z.G., Markovsky, B.A., Tararin, I.A., Ekimova, N.I., Chubarov, V.M.Fluid silicate seperation of an ultrabasic melt into high potassium and low potassium fractions: evidence from picrites of the Late Cretaceous ultrabasic volcanic complex, eastern Kamchatka.Russian Journal of Pacific Geology, Vol. 12, 5, pp. 408-418.Russia, Kamchatkapicrites

Abstract: The mineral and chemical compositions of the layered subvolcanic ultrabasic rocks formed through fluid-silicate (liquid) separation of the ultrabasic magma into high-potassium and low-potassium fractions are characterized by the example of the layered picritic sill from the Late Cretaceous ultrabasic volcanic complex of Eastern Kamchatka. It is determined that the main potassium concentrator in the picrites from the high-potassium layers is a residual volcanic glass containing up to 8-9 wt % K2O, which is unique for ultrabasic melts.
DS201212-0096
2012
Marks, A.Bulanova, G.P., Marks, A., Smith, C.B., Kohn, S.C., Walter, M.J., Gaillou, E., Shiry, S.B., Trautman, R., Griffin, B.J.Diamonds from Sese and Murowa kimberlites ( Zimbabwe) - evidence of extreme peridotitic lithosphere depletion and Ti-REE metasomatism.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, ZimbabweDeposit - Sese, Murowa
DS201212-0367
2012
Marks, A.Kohn, S.C., McKay, A.P., Smith, C.B., Bulanova, G.P., Walter, M.J., Marks, A.The thermal history of Archean lithosphere. Constraints from FTIR studies of zoning in diamonds.emc2012 @ uni-frankfurt.de, 1p. AbstractAfrica, ZimbabweDeposit - Murowa
DS201812-2784
2018
Marks, A.Bulanova, G.P., Smith, C.B., Pearson, D.G., Kohn, S.C., Davy, A.T., McKay, A., Marks, A.Murowa deposit: Diamonds from the Murowa kimberlites: formation within extremely depleted and metasomatized Zimbabwean peridotitic subcontinental mantle.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 425-Africa, Zimbabwedeposit - Murowa
DS1981-0312
1981
Marks, G.P.Nichols, I.A., Ferguson, J., Jones, H., Marks, G.P., Mutter, J.C.Ultramafic Blocks from the Ocean Floor Southwest of AustraliEarth and Planetary Science Letters, Vol. 56, PP. 362-374.Australia, Western AustraliaUltrabasic, Rocks, Lherzolite, Sea Floor Dredging
DS1984-0484
1984
Marks, J.Marrs, R.W., Marks, J., Hausel, W.D., Albert, K.G.Detection of Diamond Bearing Kimberlites in the Colorado Wyoming Province. #2Nasa Jet Propulsion Laboratory, Final Report Dated Sept. 28t, 70P.United States, Colorado, Wyoming, State Line, Rocky MountainsRemote Sensing, Geochemistry, Sampling, Prospecting, Geophysics
DS1983-0433
1983
Marks, J.E.Marks, J.E., Marrs, R.W.Remote Sensing Exploration for Poorly Exposed Kimberlite In the Colorado-Wyoming Region.Geological Survey WYOMING, Publishing INF. Circular No. 19, PP. 11-13.United States, Colorado, Wyoming, State Line, Rocky MountainsLandsat
DS1984-0485
1984
Marks, J.E.Marrs, R.W., Marks, J.E., Hausel, W.D., Albert, G.K.Detection of Diamond Bearing Kimberlites in the Colorado Wyoming Province. #1International Symposium on Remote Sensing of Environment., THIRD THEMATIC CONFERENCE, APRIL 16TH.-19TH. 11P.United States, State Line, Colorado, WyomingLandsat, Remote Sensing, Geophysics, Analyses, Diatreme
DS1985-0414
1985
Marks, J.E.Marks, J.E.Multispectral Remote Sensing Techniques Applied to Exploration for Kimberlite Distremes, Laramie Range, Wyoming-colorado.Msc. Thesis, University Wyoming, 164P.United States, State Line, Colorado, Wyoming, Laramie RangeRemote Sensing
DS2001-0732
2001
Marks, K.M.Marks, K.M., Tikku, A.A.Cretaceous reconstructions of the East Antarctica, Africa and MadagascarEarth and Planetary Science Letters, Vol. 186, No. 3-4, Apr. 15, pp. 479-96.Madagascar, Africa, AntarcticaTectonics, Gondwana
DS201112-0266
2011
Marks, M.Derrey, I., Hettmann, K., Thaler, F., Wenzel, T., Marks, M., Markl, G.Sulfur content and speciation in sodalite and its possible use as redox proxy.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologySodalite
DS201112-0369
2011
Marks, M.Giehl, C., Bellucci, P., Nguyen, H-T., Marks, M., Nowak, M.Experimental investigation of the differentiation of iron rich peralkaline magma.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologyMagmatism
DS201112-0433
2011
Marks, M.Hettmann, K., Marks, M., Kressing, K., Zack, T., Wenzel, T., Rehkamper, M., Jacob, D., Markl, G.The geochemistry of thallium and its isotopes in a peralkaline magmatic system.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologyMagmatism
DS201112-0604
2011
Marks, M.Lindhuber, M., Marks, M., Wenzel, T., Markl, G.Igneous layering in peralkaline rocks of the Ilmaussaq intrusion, Greenland.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterEurope, GreenlandAlkalic
DS201112-0644
2011
Marks, M.Marks, M.Critical factors for the transition from miaskitic to agpaitic rocks: the role of f02,Na2O and K2O and CaO.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, AbstractGeochemistry
DS201112-0846
2011
Marks, M.Ratschbacher, B., Pfaff, K., Marks, M., Markl, G.Geochemical trends within the lujavrites of the Ilmaussaq intrusion, SW Greenland.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterEurope, GreenlandAlkalic
DS201909-2050
2019
Marks, M.Hutchison, W., Baiel, R., Finch, A., Marks, M., Markl, G., Boyce, A., Stueken, E., Friis, H., Borst, A., Horsburgh, N.Sulphur isotopes of alkaline igneous suites: new insights into magmatic fluid evolution and crustal recycling.Goldschmidt2019, 1p. AbstractGlobalalkaline rocks
DS202109-1494
2021
Marks, M.A.Walter, B.F., Giebel, R.J., Steele-MacInnis, M., Marks, M.A., Kolb, J., Markl, G.Fluids associated with carbonatitic magmatism: a critical review and implications for carbonatite magma ascent.Earth Science Reviews , Vol. 215, 103509, 27p. PdfMantlemagmatism

Abstract: Carbonatites are formed from volatile-rich melts, commonly associated with a characteristic hydrothermal footprint. However, studies of their fluid inclusions are relatively scarce and heterogeneous in terms of detail and completeness of the data presented. Here, we review and discuss comprehensively the results of previous studies and derive a general model for the formation and properties of fluids associated with carbonatitic magmatism. Worldwide, four types of fluid inclusion occur in carbonatites: (type I/HS) vapour-poor H2O-NaCl fluids with up to 50 wt% salinity; (type II/HC) vapour-rich H2O-NaCl-CO2 fluids with <5 wt% salinity; (type III/DS) multi-component fluids with high salinity and without CO2; and (type IV/CDS) multi-component fluids with high salinity and high CO2. This global dataset suggests continuous fluid release from deep to shallow-level intrusions. Modelling of the liquidus surface indicates that carbonatite magmas generally exsolve a saline brine (type I/HS). This brine separates/evolves into a Na-K-sulfate-carbonate/bicarbonate-chloride brine with or without CO2 (types III/DS and IV/CDS), trapped together with low salinity CO2-rich fluids produced by immiscibility. Fluid immiscibility is related to rapid pressure release during fast, forceful and discontinuous magma ascent, which we envisage as a "pneumatic jackhammer" model for carbonatite ascent and emplacement. In this model, cyclic and progressive fluid flux via pressure build-up and subsequent catastrophic pressure release results in a self-sustaining crustal ascent of the buoyant, low-viscosity magma. This process allows for rapid and efficient magma ascent, in particular above the brittle-ductile transition zone, where pressures that prevailed during apatite crystallization have been estimated in numerous complexes. Moreover, this model provides an explanation for the apparent absence of shallow carbonatite magma chambers (in a classical sense) and identifies fenitization as a phenomenon induced by both fluids released during magma ascent and residual fluids.
DS200712-0681
2007
Marks, M.A.W.Marks, M.A.W., Rudnick, R.L., McCammon, C., Vennemann, T., Markl, G.Arrested kinetic Li isotope fractionation at the margin of the Ilimaussaq complex: evidence for open system processes during final cooling peralkaline igneous rocksChemical Geology, Vol. 246, 3-4, pp. 207-230.Europe, GreenlandGeochronology
DS200912-0473
2009
Marks, M.A.W.Marks, M.A.W., Neukirchen, F., Vennemann, T., Markl, G.Textural, chemical and isotopic effects of late magmatic carbonatitic fluids in the carbonatite syenite Tamazeght complex, High Atlas Mountains, Morocco.Mineralogy and Petrology, Vol. 97, pp. 23-42.Africa, MoroccoCarbonatite
DS201112-0645
2011
Marks, M.A.W.Marks, M.A.W., Hettmann, K., Schilling, J., Frost, B.R., Markl, G.The mineralogical diversity of alkaline igneous rocks: critical factors for the transition from miaskitic to agpaitic phase assemblages.Journal of Petrology, Vol. 52, 3, pp. 439-455.Alkalic
DS201112-0924
2011
Marks, m.A.W.Schilling, J., Marks, m.A.W., Wenzel, T., Vennenmann, T., Horvth, L., Tarassof, P., Jacob, D.E., Markl, G.The magmatic to hydrothermal evolution of the intrusive Mont Sainte Hilaire Complex: insights into the late stage evolution of peralkaline rocks.Journal of Petrology, Vol. 52, 11. pp. 2147-2185.Canada, QuebecAlkaline rocks, carbonatite
DS201212-0810
2012
Marks, M.A.W.Zaitsev, A.N., Marks, M.A.W., Wenzel, T., Spratt, W.J., Sharygin, V.V., Strekoptov, G.M.Mineralogy, geochemistry and petrology of the phonolitic to nephelinitic Sadiman volcano, Crater Highlands, Tanzania.Lithos, Vol. 152, pp. 66-83.Africa, TanzaniaNephelinite
DS201312-0952
2013
Marks, M.A.W.Wang, L., Wenzel, T., Vonder Handt, A., Keller, J., Marks, M.A.W., Markl, G.Compositional variation in apatites from carbonatites and associated silicate rocks: a case study of the Kaiserstuhl complex, Germany.Goldschmidt 2013, 1p. AbstractEurope, GermanyCarbonatite
DS201412-0545
2014
Marks, M.A.W.Mangler, M.F., Marks, M.A.W., Zaitsev, A.N., Eby, G.N., Markl, G.Halogens (F, Cl and Br) at Oldoinyo Lengai volcano ( Tanzania): effects of magmatic differentiation, silicate, natrocarbonatite melt seperation and surface alteration of natrocarbonatite.Chemical Geology, Vol. 365, pp. 43-53.Africa, TanzaniaCarbonatite
DS201412-0962
2014
Marks, M.A.W.Wang, L-X., Marks, M.A.W., Wenzel, T., Vonder Handt, A., Keller, J., Teiber, H., Markl, G.Apatites from the Kaiserstuhl volcanic complex, Germany: new constraints on the relationship between carbonatite and associated silicate rocks.European Journal of Mineralogy, Vol. 26, pp. 397-414.Europe, GermanyCarbonatite
DS201604-0617
2016
Marks, M.A.W.Ladenburger, S., Marks, M.A.W., Upton, B., Hill, P., Wenzel, T., Markl, G.Compositional variation of apatite from rift related alkaline igneous rocks of the Gardar Province, South Greenland.American Mineralogist, Vol. 101, pp. 612-626.Europe, GreenlandAlkalic

Abstract: Textural and compositional variations of apatite from four intrusions with different characteristic features of the rift-related alkaline Gardar Province were investigated: dyke rocks that belong to the most primitive rocks of the Province (Isortoq), nepheline-syenites associated with a carbonatite (Grønnedal-Ika), SiO2-saturated and SiO2-oversaturated syenites (Puklen) and nepheline-syenites displaying the transition from miaskitic to agpaitic mineral assemblages (Motzfeldt, Fig.1). Additionally, apatites from these intrusions were compared with other apatites of the Gardar Province. These include apatites from the Older Giant Dyke Complex, the Younger Giant Dyke Complex (both from the Tugtutôq region) and a narsarsukite-bearing trachytic dyke (Igdlutalik), as well as apatites from the Kûngnât, the North Qôroq and the Ilímaussaq intrusive complexes. This results in a complete overview of rift-related magmatites of the Gardar Province, ranging from primitive to highly evolved rocks. Backscattered electron images reveal the presence of various types of apatite textures including (i) growth zonation (concentric and oscillatory) that formed during magmatic differentiation and (ii) overgrowth and secondary textures (rounded cores, patchy zonation and overgrowth rims) due to fluid/melt induced metasomatic overprint and intracrystalline diffusion (Fig.2). Additionally, apatite compositions were analyzed with wavelength-dispersive electron microprobe analyses. During the crystallization history of the different intrusions, as well as within samples (documented by zoning patterns), increasing concentrations are observed for Si, REE, Na and F, whereas Cl shows a decreasing trend. However, for F, Cl and Na these trends are only observed in dyke rocks. Compositional variation of the investigated apatites is mainly due to substitution of Ca and P by variable amounts of Si, Na and REE. This study reveals that variations in the chemical composition of apatite are useful tools to obtain geochemical information about the host magma and its magmatic evolution. Here, Si and REE were found to be reliable petrogenetic indicators, whereas Na, F and Cl are only applicable in fast cooling systems to avoid redistribution of those elements.
DS201707-1326
2017
Marks, M.A.W.Giebel, R.J., Gauert, C.D.K., Marks, M.A.W., Costin, G., Markl, G.Multi stage formation of REE minerals in the Palabora carbonatite complex, South Africa.American Mineralogist, Vol. 102, pp. 1218-1233.Africa, South Africacarbonatite - Palabora

Abstract: The 2060 Ma old Palabora Carbonatite Complex (PCC), South Africa, comprises diverse REE mineral assemblages formed during different stages and reflects an outstanding instance to understand the evolution of a carbonatite-related REE mineralization from orthomagmatic to late-magmatic stages and their secondary post-magmatic overprint. The 10 rare earth element minerals monazite, REE-F-carbonates (bastnäsite, parisite, synchysite), ancylite, britholite, cordylite, fergusonite, REE-Ti-betafite, and anzaite are texturally described and related to the evolutionary stages of the PCC. The identification of the latter five REE minerals during this study represents their first described occurrences in the PCC as well as in a carbonatite complex in South Africa. The variable REE mineral assemblages reflect a multi-stage origin: (1) fergusonite and REE-Ti-betafite occur as inclusions in primary magnetite. Bastnäsite is enclosed in primary calcite and dolomite. These three REE minerals are interpreted as orthomagmatic crystallization products. (2) The most common REE minerals are monazite replacing primary apatite, and britholite texturally related to the serpentinization of forsterite or the replacement of forsterite by chondrodite. Textural relationships suggest that these two REE-minerals precipitated from internally derived late-magmatic to hydrothermal fluids. Their presence seems to be locally controlled by favorable chemical conditions (e.g., presence of precursor minerals that contributed the necessary anions and/or cations for their formation). (3) Late-stage (post-magmatic) REE minerals include ancylite and cordylite replacing primary magmatic REE-Sr-carbonates, anzaite associated with the dissolution of ilmenite, and secondary REE-F-carbonates. The formation of these post-magmatic REE minerals depends on the local availability of a fluid, whose composition is at least partly controlled by the dissolution of primary minerals (e.g., REE-fluorocarbonates). This multi-stage REE mineralization reflects the interplay of magmatic differentiation, destabilization of early magmatic minerals during subsequent evolutionary stages of the carbonatitic system, and late-stage fluid-induced remobilization and re-/precipitation of precursor REE minerals. Based on our findings, the Palabora Carbonatite Complex experienced at least two successive stages of intense fluid–rock interaction.
DS201802-0233
2018
Marks, M.A.W.Elliott, H.A.L., Wall, F., Chakmouradian, A.R., Siegfried, P.R., Dahlgren, S., Weatherley, S., Finch, A.A., Marks, M.A.W., Dowman, E., Deady, E.Fenites associated with carbonatite complexes: a review.Ore Geology Reviews, Vol. 92, pp. 38-59.Globalcarbonatites

Abstract: Carbonatites and alkaline-silicate rocks are the most important sources of rare earth elements (REE) and niobium (Nb), both of which are metals imperative to technological advancement and associated with high risks of supply interruption. Cooling and crystallizing carbonatitic and alkaline melts expel multiple pulses of alkali-rich aqueous fluids which metasomatize the surrounding country rocks, forming fenites during a process called fenitization. These alkalis and volatiles are original constituents of the magma that are not recorded in the carbonatite rock, and therefore fenites should not be dismissed during the description of a carbonatite system. This paper reviews the existing literature, focusing on 17 worldwide carbonatite complexes whose attributes are used to discuss the main features and processes of fenitization. Although many attempts have been made in the literature to categorize and name fenites, it is recommended that the IUGS metamorphic nomenclature be used to describe predominant mineralogy and textures. Complexing anions greatly enhance the solubility of REE and Nb in these fenitizing fluids, mobilizing them into the surrounding country rock, and precipitating REE- and Nb-enriched micro-mineral assemblages. As such, fenites have significant potential to be used as an exploration tool to find mineralized intrusions in a similar way alteration patterns are used in other ore systems, such as porphyry copper deposits. Strong trends have been identified between the presence of more complex veining textures, mineralogy and brecciation in fenites with intermediate stage Nb-enriched and later stage REE-enriched magmas. However, compiling this evidence has also highlighted large gaps in the literature relating to fenitization. These need to be addressed before fenite can be used as a comprehensive and effective exploration tool.
DS201811-2617
2018
Marks, M.A.W.Walter, B.F., Parsapoor, A., Braunger, S., Marks, M.A.W., Wenzel, T., Martin, M., Markl, G.Pyrochlore as a monitor for magmatic and hydrothermal processes in carbonatites from the Kaiserstuhl volcanic complex ( SW Germany).Chemical Geology, Vol. 498, pp. 1-16.Europe, Germanycarbonatite

Abstract: Pyrochlore from the Kaiserstuhl volcanic complex (SW Germany) shows textural and compositional differences between various coarse-grained calcite-carbonatite bodies (Badberg, Degenmatt, Haselschacher Buck, Orberg) and extrusive carbonatites (Henkenberg, Kirchberg). Oscillatory-zoned F-rich pyrochlore with up to 69?wt% Nb2O5 is common in all coarse-grained calcite-carbonatite bodies and probably formed during magmatic conditions. However, only in some of the samples from the Badberg, partly resorbed U- and Ta-enriched pyrochlore cores with up to 22?wt% UO2 and 9?wt% Ta2O5 have been identified, which are interpreted as being inherited from underlying nosean syenites. Pyrochlore data from a drill core penetrating the Badberg indicate increasing contents of REE, U, and Ta with depth, while Nb, F and Na contents decrease. This may reflect the combined effects of fractional crystallization and assimilation (AFC) or indicates a multi-stage emplacement of the carbonatitic magma. Patchy-zoned ceriopyrochlore and REE- and Th-enriched pyrochlore with up to 19?wt% total REE2O3 and 6.5?wt% ThO2 is largely restricted to samples from the Orberg and probably formed during hydrothermal conditions. This can be related to the relatively evolved character of the Orberg carbonatites, based on their relatively high whole-rock Nb/Ta and Zr/Hf mass ratios. This study demonstrates that the textural and compositional variation of pyrochlore in carbonatites is a powerful tool to distinguish magmatic, hydrothermal and weathering processes in carbonatitic systems.
DS201812-2810
2019
Marks, M.A.W.Giebel, R.J., Marks, M.A.W., Gauert, C.D.K., Markl, G.A model for the formation of carbonatite-phoscorite assemblages based on the compositional variations of mica and apatite from the Palabora carbonatite complex, South Africa.Lithos, Vol. 324-325, pp. 89-104.Africa, South Africadeposit - Palabora

Abstract: A detailed electron microprobe study has been carried out on the compositional variations of mica and apatite from carbonatites, phoscorites and associated pyroxenites (and fenites) of the Loolekop deposit, Palabora Carbonatite Complex (South Africa). Mica in pyroxenites and fenites is Mg-rich biotite, whilst micas in carbonatites and phoscorites are compositionally diverse including phlogopite, Ba-rich phlogopite (up to 30% kinoshitalite component), IVAl-rich phlogopite (up to 30% eastonite component) and tetraferriphlogopite. The various types of phlogopites are interpreted as orthomagmatic phases, whereas tetraferriphlogopite precipitation was a late-magmatic to hydrothermal process that additionally introduced REE into the system. Orthomagmatic apatite is generally REE- and Sr-poor fluorapatite and does not show large compositional differences between rock types. Apatite associated with the late-stage tetraferriphlogopite mineralization reaches higher levels of REE (up to 4.9?wt%), Si (up to 1.5?wt% SiO2), Sr (up to 2.6?wt% SrO) and Na (up to 1.0?wt% Na2O). The compositional variation of micas and apatites, which is affiliated with distinct rock types, reflects the multi-stage evolution of the Loolekop deposit and provides detailed insight into the relationships of the carbonatite-phoscorite assemblage. The obtained data support the separation of phoscorite and carbonatite by immiscibility from a common parental magma, which may happen due to a decrease of temperature and/or pressure during the ascent of the magma. This results in a density contrast between the carbonatitic and phoscoritic components that will lead to descending phoscorite accumulations at the outer zones of the magma channel and a jet-like ascent (further promoted by its extremely low viscosity) of the carbonatite magma. The genetic model deduced here explains the peculiar association of carbonatites, phoscorites and silicate rocks in many alkaline complexes worldwide.
DS201902-0273
2019
Marks, M.A.W.Giebel, R.J., Marks, M.A.W., Gauert, C.K., Markl, G.A model for the formation of carbonatite-phoscorite assemblages based on the compositonal variations of mica and apatite from the Palabora carbonatite complex, South AfricaLithos, Vol. 324, pp. 68-73.Europe, Azoresdeposit - Palabora

Abstract: A detailed electron microprobe study has been carried out on the compositional variations of mica and apatite from carbonatites, phoscorites and associated pyroxenites (and fenites) of the Loolekop deposit, Palabora Carbonatite Complex (South Africa). Mica in pyroxenites and fenites is Mg-rich biotite, whilst micas in carbonatites and phoscorites are compositionally diverse including phlogopite, Ba-rich phlogopite (up to 30% kinoshitalite component), IVAl-rich phlogopite (up to 30% eastonite component) and tetraferriphlogopite. The various types of phlogopites are interpreted as orthomagmatic phases, whereas tetraferriphlogopite precipitation was a late-magmatic to hydrothermal process that additionally introduced REE into the system. Orthomagmatic apatite is generally REE- and Sr-poor fluorapatite and does not show large compositional differences between rock types. Apatite associated with the late-stage tetraferriphlogopite mineralization reaches higher levels of REE (up to 4.9?wt%), Si (up to 1.5?wt% SiO2), Sr (up to 2.6?wt% SrO) and Na (up to 1.0?wt% Na2O). The compositional variation of micas and apatites, which is affiliated with distinct rock types, reflects the multi-stage evolution of the Loolekop deposit and provides detailed insight into the relationships of the carbonatite-phoscorite assemblage. The obtained data support the separation of phoscorite and carbonatite by immiscibility from a common parental magma, which may happen due to a decrease of temperature and/or pressure during the ascent of the magma. This results in a density contrast between the carbonatitic and phoscoritic components that will lead to descending phoscorite accumulations at the outer zones of the magma channel and a jet-like ascent (further promoted by its extremely low viscosity) of the carbonatite magma. The genetic model deduced here explains the peculiar association of carbonatites, phoscorites and silicate rocks in many alkaline complexes worldwide.
DS201903-0498
2019
Marks, M.A.W.Banks, G.J., Walter, B.F., Marks, M.A.W., Siegfried, P.R.A workflow to define, map and name a carbonatite-alkaline igneous-associated REE-HFSE mineral system: a case study from SW Germany.MDPI, Vol. 9, 97, 28p. PdfGlobalREE

Abstract: Security of supply of “hi-tech” raw materials (including the rare earth elements (REE) and some high-field-strength elements (HFSEs)) is a concern for the European Union. Exploration and research projects mostly focus on deposit- to outcrop-scale description of carbonatite- and alkaline igneous-associated REE-HFSE mineralization. The REE-HFSE mineral system concept and approach are at a nascent stage, so developed further here. However, before applying the mineral system approach to a chosen REE-HFSE metallogenic province its mineral system extent first needs defining and mapping. This shifts a mineral system project’s foundation from the mineral system concept to a province’s mineral system extent. The mapped extent is required to investigate systematically the pathways and potential trap locations along which the REE-HFSE mass may be distributed. A workflow is presented to standardize the 4-D definition of a REE-HFSE mineral system at province-scale: (a) Identify and hierarchically organize a mineral system’s genetically related sub-divisions and deposits, (b) map its known and possible maximum extents, (c) name it, (d) discern its size (known mineral endowment), and (e) assess the favorability of the critical components to prioritize further investigations. The workflow is designed to generate process-based perspective and improve predictive targeting effectiveness along under-evaluated plays of any mineral system, for the future risking, comparing and ranking of REE-HFSE provinces and plays.
DS201909-2024
2019
Marks, M.A.W.Braunger, S., Marks, M.A.W., Wenzel, T., Chmyz, L., Azzone, R.G., Markl, G.Carbonatite-alkaline silica rock complexes reflect highly oxidized conditions in their Upper Mantle source.Goldschmidt2019, 1p. AbstractMantlecarbonatite

Abstract: Alkaline complexes consist of variable mantle-derived silicate rocks, ranging from primitive alkali basalts, melilitites, nephelinites and basanites towards tephrites and more evolved phonolites, respectively their plutonic equivalents. This lithological variance is also expressed by a wide range of redox conditions that vary by several log units around the synthetic fayalite-magnetite-quartz (FMQ) buffer. However, only some of these complexes are characterized by the occurrence of carbonatites which must be related to specific formation conditions. Based on textural, mineralogical and geochemical observations, we calculated the redox conditions of carbonatites and associated silicate rocks for seven alkaline complexes (Kaiserstuhl, Sokli, Kovdor, Palabora, Magnet Cove, Oka, Jacupiranga) which are considered to represent typical carbonatite-alkaline silicate rock associations. In combination with a comprehensive literature review, we demonstrate that carbonatite-bearing alkaline complexes formed under highly oxidized conditions and hence, belong to the most oxidized alkaline rocks at all. This is consistent with the prerequisite of a carbonated mantle as the source region for carbonatite complexes, which requires redox conditions distinctively above that for mean lithospheric or asthenospheric mantle. Carbonatitemetasomatized peridotites also show high redox conditions and might not only reflect an interaction between peridotite and carbonatitic melts/fluids, but at least partly represent the carbonated mantle source for crustally emplaced carbonatite complexes. We therefore suggest that the oxidation state of carbonatites and associated silicate rocks provides direct information about an extraordinary oxidized parental mantle source.
DS201909-2041
2019
Marks, M.A.W.Giebel, R.J., Marks, M.A.W., Gauert, C.D.K., Markl, G.A model for the formation of carbonatite-phoscorite assemblages.Goldschmidt2019, 1p. AbstractGlobalcarbonatite

Abstract: A detailed electron microprobe study has been carried out on the compositional variations of mica and apatite from carbonatites, phoscorites and associated pyroxenites (and fenites) of the Loolekop deposit, Palabora Carbonatite Complex (South Africa). Mica in pyroxenites and fenites is Mg-rich biotite, whilst micas in carbonatites and phoscorites are compositionally diverse including phlogopite, Ba-rich phlogopite (up to 30% kinoshitalite component), IVAl-rich phlogopite (up to 30% eastonite component) and tetraferriphlogopite. The various types of phlogopites are interpreted as orthomagmatic phases, whereas tetraferriphlogopite precipitation was a late-magmatic to hydrothermal process that additionally introduced REE into the system. Orthomagmatic apatite is generally REE- and Sr-poor fluorapatite and does not show large compositional differences between rock types. Apatite associated with the late-stage tetraferriphlogopite mineralization reaches higher levels of REE (up to 4.9?wt%), Si (up to 1.5?wt% SiO2), Sr (up to 2.6?wt% SrO) and Na (up to 1.0?wt% Na2O). The compositional variation of micas and apatites, which is affiliated with distinct rock types, reflects the multi-stage evolution of the Loolekop deposit and provides detailed insight into the relationships of the carbonatite-phoscorite assemblage. The obtained data support the separation of phoscorite and carbonatite by immiscibility from a common parental magma, which may happen due to a decrease of temperature and/or pressure during the ascent of the magma. This results in a density contrast between the carbonatitic and phoscoritic components that will lead to descending phoscorite accumulations at the outer zones of the magma channel and a jet-like ascent (further promoted by its extremely low viscosity) of the carbonatite magma. The genetic model deduced here explains the peculiar association of carbonatites, phoscorites and silicate rocks in many alkaline complexes worldwide.
DS201909-2042
2019
Marks, M.A.W.Giebel, R.J., Parsapoor, A., Walter, B.F., Braunger, S., Marks, M.A.W.Evidence for magma-wall rock interaction in carbonatites from the Kaiserstuhl volcanic complex ( southwest Germany).Journal of Petrology , Vol. 60, 6, pp. 1163-1194.Europe, Germanycarbonatite

Abstract: The mineralogy and mineral chemistry of the four major sövite bodies (Badberg, Degenmatt, Haselschacher Buck and Orberg), calcite foidolite/nosean syenite xenoliths (enclosed in the Badberg sövite only) and rare extrusive carbonatites of the Kaiserstuhl Volcanic Complex in Southern Germany provide evidence for contamination processes in the carbonatitic magma system of the Kaiserstuhl. Based on textures and composition, garnet and clinopyroxene in extrusive carbonatites represent xenocrysts entrained from the associated silicate rocks. In contrast, forsterite, monticellite and mica in sövites from Degenmatt, Haselschacher Buck and Orberg probably crystallized from the carbonatitic magma. Clinopyroxene and abundant mica crystallization in the Badberg sövite, however, was induced by the interaction between calcite foidolite xenoliths and the carbonatite melt. Apatite and micas in the various sövite bodies reveal clear compositional differences: apatite from Badberg is higher in REE, Si and Sr than apatite from the other sövite bodies. Mica from Badberg is biotite- and comparatively Fe2+-rich (Mg# = 72-88). Mica from the other sövites, however, is phlogopite (Mg# up to 97), as is typical of carbonatites in general. The typical enrichment of Ba due to the kinoshitalite substitution is observed in all sövites, although it is subordinate in the Badberg samples. Instead, Badberg biotites are strongly enriched in IVAl (eastonite substitution) which is less important in the other sövites. The compositional variations of apatite and mica within and between the different sövite bodies reflect the combined effects of fractional crystallization and carbonatite-wall rock interaction during emplacement. The latter process is especially important for the Badberg sövites, where metasomatic interaction released significant amounts of K, Fe, Ti, Al and Si from earlier crystallized nosean syenites. This resulted in a number of mineral reactions that transformed these rocks into calcite foidolites. Moreover, this triggered the crystallization of compositionally distinct mica and clinopyroxene crystals around the xenoliths and within the Badberg sövite itself. Thus, the presence and composition of clinopyroxene and mica in carbonatites may be useful indicators for contamination processes during their emplacement. Moreover, the local increase of silica activity during contamination enabled strong REE enrichment in apatite via a coupled substitution involving Si, which demonstrates the influence of contamination on REE mineralization in carbonatites.
DS201909-2061
2019
Marks, M.A.W.Marks, M.A.W., Giebel, R.J., Walter, B.F., Braunger, S., Wenzel, T., Markl, G.Evidence for wall-rock assimilation in carbonatites from the Kaiserstuhl (German).Goldschmidt2019, 1p. AbstractEurope, Germanydeposit - Kaiserstuhl

Abstract: Contamination of carbonatites with crustal or cogenetic intrusive rocks is generally not considered to play an important role during carbonatite magmatism, because carbonatitic melts have low densities and viscosities, enabling them to rapidly ascend. Potential contamination by silicate rocks in carbonatites cannot easily be detected by means of radiogenic isotope data (such as Sr, Nd and Pb isotope data) as carbonatites often show high concentrations of these elements and their isotope systems are thereby “buffered” against contamination with silicate rocks. Textural, mineralogical and geochemical observations in carbonatites from the Kaiserstuhl (Germany) provide evidence for the interaction of carbonatitic magma with previously emplaced nosean syenites. This caused replacement of alkali feldspar by haüyne and recrystallization of garnet and clinopyroxene in the xenoliths, which released larger amounts of K, Al, Si and Fe. As a result, blackwall-like mica seams around the xenoliths formed and and compositionally distinct mica and clinopyroxene crystallized in the surrounding carbonatite. Moreover, the local increase of silica activity during contamination enabled strong REE enrichment in apatite via a coupled substitution involving Si, which demonstrates the potential influence of Si contamination on REE mineralization in carbonatites. We further suggest that the presence and composition of clinopyroxene and mica in carbonatites may be useful indicators for contamination processes during their emplacement. Mass-balance calculations based on experimental constraints for the solubility of Al and Si in carbonatitic magmas suggest that only minor amounts of mica can form from carbonatitic melt. Therefore, larger amounts of mica and mica-dominated lithologies (glimmerites) as observed in many carbonatite complexes suggest that some Si and Al in carbonatites may be sourced from surrounding host rocks. We hypothesize that assimilation and contamination processes in carbonatites may be the rule rather than an exception.
DS201909-2104
2019
Marks, M.A.W.Walter, B.F., Steele-MacInnis, M., Giebel, R.J., Marks, M.A.W., Markl, G.Fluids exsolved from the Kaiserstuhl carbonatite, SW Germany: brine generation by boiling.Goldschmidt2019, 1p. AbstractEurope, Germanydeposit - Kaiserstuhl

Abstract: Studies on fluid inclusions in carbonatitic rocks are essential to understand the physicochemical processes involved in carbonatite-related hydrothermal ore mineralization. Although little is known about the composition of carbonatite-derived fluids. We investigated fluid inclusions in the Kaiserstuhl carbonatites, SW Germany [1,2] and identified four different types typically known from carbonatitic systems worldwide [3]: (I): Vapor-poor H2O-NaCl fluids with <50 wt.% salinity. (II): Vapor-rich H2O-NaCl-CO2 fluids with <5 wt.% salinity. (III): Multi-component fluids with high salinity and CO2. (IV): Multi-component fluids with high salinity, no CO2. Homogenization temperatures (156 to 530°C) of all fluid types generally show a wide range [this study, 2]. Primary type I fluid inclusions occur in early magmatic olivine/monticellite, as well as paragenetically later apatites and calcites [2]. This indicates a ubiquitous existence of a saline brine, which does not reach saturation with respect to halite, during early to late crystallization stages. Liquidus surface modelling based quantifications for fluid type III suggest that carbonatite melts predomonantly exsolve Na-K-sulfate-carbonate/bicarbonate-chloride brines (type III or IV, respectively). Such fluid inclusions, with type III (CO2-free) on one side and type IV (and II, both CO2-rich) on the other side, may represent immiscible fluids that were trapped after segregation by boiling from a parental highly saline brine (type I). Fluid boiling, in turn, is probably triggered by a rapid pressure release during “pneumatic hammer-like,” discontinuous melt ascent.
DS202002-0168
2020
Marks, M.A.W.Braunger, S., Marks, M.A.W., Wenzel, T., Chmyz, L., Azzone, R.G., Markl, G.Do carbonatites and alkaline rocks reflect variable redox conditions in their upper mantle source? ( metasomatism)Earth and Planetary Science Letters, Vol. 533, 11p. PdfMantlecarbonatite

Abstract: A detailed investigation on seven carbonatites and associated alkaline rock complexes (Kaiserstuhl, Sokli, Kovdor, Palabora, Oka, Magnet Cove, Jacupiranga), together with a world-wide comparison between carbonatites, alkaline silicate rocks and mantle xenoliths, implies peculiar redox conditions for carbonatite-bearing alkaline complexes: Carbonatites and associated alkaline rocks in continental settings crystallize from relatively oxidized magmas, on average 1.4 log units () and 1.3 log units () above the synthetic fayalite-magnetite-quartz (FMQ) buffer. In contrast, alkaline rocks in continental settings that lack associated carbonatites reveal rather reduced conditions (mean ; ). The calculated redox conditions for carbonatites and associated silicate rocks demonstrate that these crystallize from relatively oxidized mantle-derived melts compared to the general range found for alkaline rocks in continental settings.
DS202006-0955
2020
Marks, M.A.W.Walter, B.F., Steele-MacInnis, M., Giebel, R.J., Marks, M.A.W., Markl, G.Complex carbonatite-sulfate brines in fluid inclusions from carbonatites: estimating compositions in the system H2O-Na-K-CO3-SO4-Cl. KaiserstuhlGeochimica et Cosmochimica Acta, Vol. 277, pp. 224-242. pdfEurope, Germanycarbonatite

Abstract: Studies of fluid inclusions in carbonatitic rocks are essential for understanding physicochemical processes involved in carbonatite-related hydrothermal ore mineralization and fenitization. However, the composition of many carbonatite-derived fluids is challenging to quantify, which hampers their detailed interpretation. Here, we present a systematic study of microthermometry of fluid inclusions found in carbonatites from the Kaiserstuhl (SW Germany), and a simple numerical model to estimate the compositions of such fluids, which are typical of numerous carbonatites worldwide. Four types of fluid inclusions have been identified in the Kaiserstuhl carbonatites: (I) vapor-poor H2O-NaCl fluids with <50?wt.% salinity; (II) vapor-rich H2O-NaCl-CO2 fluids with <5?wt.% salinity; (III) multi-component fluids with high salinity and high CO2 contents; and (IV) multi-component fluids with high salinity but little to no CO2. At present, it is only possible to quantify fluid compositions for types I and II. For the complex types III and IV, we conducted predictive modeling of the liquidus surface based on the Margules equations. The results suggest that carbonatite melts predominantly exsolve Na-K-sulfate-carbonate/bicarbonate-chloride brines (types III or IV). Such fluid inclusions may represent immiscible fluids that were trapped after segregation by boiling from a parental highly saline brine (type I). Fluid boiling, in turn, was probably triggered by a rapid pressure release during melt ascent. The present model enables quantification of fluid compositions associated with carbonatitic magmatism.
DS202007-1145
2020
Marks, M.A.W.Hecker, J.G., Marks, M.A.W., Wenzel, T., Markl, G.Halogens in amphibole and mica from mantle xenoliths: implications for the halogen distribution and halogen budget of the metasomatized continental lithosphere.American Mineralogist, Vol. 105, pp. 781-794.Mantlemetasomatism

Abstract: This study reports halogen contents (F and Cl) of amphibole and phlogopite derived from mantle xenoliths and one peridotite massif, for amphibole and phlogopite megacrysts and ultramafic magmatic cumulates (hornblendites) found in alkaline volcanic rocks from 12 localities in Europe and Africa. Amphibole and phlogopite contain more F than Cl with F/Cl ratios reaching about 160 in phlogopites and 50 in amphiboles. Phlogopites are higher in F (median of 3400 ?g/g) than amphibole (median of 1000 ?g/g), while median Cl contents are higher in amphibole (290 ?g/g) compared to phlogopite (180 ?g/g). The Cl contents and the F/Cl ratios in amphibole and phlogopite from mantle xenoliths exhibit large differences between samples of the same region, recording very large variations of halogen contents in the continental lithosphere. We suggest that the halogen content in such samples largely depends on the initial composition of percolating melts and fluids in the continental lithosphere. During reaction of these agents with peridotitic wall-rocks, Cl is preferentially retained in the fluid as it is much more incompatible compared to water and F. This desiccation effect continuously increases salinity (Cl content) and decreases the F/Cl ratio in the agent with time, causing variable Cl contents and F/Cl ratios in amphibole and phlogopite at a specific locality. Subsequent partial melting processes may then sequester and re-distribute, especially Cl among amphibole, phlogopite and melts/fluids as a result of its strong incompatibility, whereas F is much less affected as it behaves slightly compatible. The impact of even small amounts of amphibole and mica on the total halogen budget in the continental lithosphere is significant and both minerals can effectively contribute to the high halogen contents typical of alkaline melts.
DS202007-1184
2020
Marks, M.A.W.Walter, B.F., Steele-MacInnis, M., Gielbel, R.J., Marks, M.A.W., Markl, G.Complex carbonatite-sulfate brines in fluid inclusions from carbonatites: estimating compositions in the system H2O-Na-K-CO3-SO4-ClGeochimica et Cosmochimica Acta, Vol. 277, pp. 224-242. pdfEurope, Germanydeposit - Kaiserstuhl

Abstract: Studies of fluid inclusions in carbonatitic rocks are essential for understanding physicochemical processes involved in carbonatite-related hydrothermal ore mineralization and fenitization. However, the composition of many carbonatite-derived fluids is challenging to quantify, which hampers their detailed interpretation. Here, we present a systematic study of microthermometry of fluid inclusions found in carbonatites from the Kaiserstuhl (SW Germany), and a simple numerical model to estimate the compositions of such fluids, which are typical of numerous carbonatites worldwide. Four types of fluid inclusions have been identified in the Kaiserstuhl carbonatites: (I) vapor-poor H2O-NaCl fluids with <50?wt.% salinity; (II) vapor-rich H2O-NaCl-CO2 fluids with <5?wt.% salinity; (III) multi-component fluids with high salinity and high CO2 contents; and (IV) multi-component fluids with high salinity but little to no CO2. At present, it is only possible to quantify fluid compositions for types I and II. For the complex types III and IV, we conducted predictive modeling of the liquidus surface based on the Margules equations. The results suggest that carbonatite melts predominantly exsolve Na-K-sulfate-carbonate/bicarbonate-chloride brines (types III or IV). Such fluid inclusions may represent immiscible fluids that were trapped after segregation by boiling from a parental highly saline brine (type I). Fluid boiling, in turn, was probably triggered by a rapid pressure release during melt ascent. The present model enables quantification of fluid compositions associated with carbonatitic magmatism.
DS202102-0198
2021
Marks, M.A.W.Hoare, B.C., Tomlinson, E.L., Barnes, J.D., Tappe, S., Marks, M.A.W., Epp, T., Caulfield, J., Riegler, T.Tracking halogen recycling and volatile loss in kimberlite magmatism from Greenland: evidence from combined F-Cl-Br and Delta 37Cl systematics.Lithos, doi;101016/j. lithos.2021.105976 78p. PdfEurope, Greenlandhalogen
DS202204-0518
2022
Marks, M.A.W.Chmyz, L., Azzone, R.G., Ruberti, E., Marks, M.A.W.Olivines as probes into assimilation of silicate rocks by carbonate magmas: unraveling the genesis of reaction rocks from the Jacupiranga alkaline-carbonatite complex, southern Brazil.Lithos, Vol. 416-417, 18p. 106647South America, Brazildeposit - Jacupiranga
DS1996-0887
1996
Marks, P.Marks, P.The mystery of the appearing diamondNew Scientist, March 23, p. 22.GlobalDiamond genesis
DS200412-0446
2004
Markwich, A.Dessai, A.G., Markwich, A., Vaselli, O., Downes, H.Granulite and pyroxenite xenoliths from the Deccan Trap: insights into the nature and composition of the lower lithosphere beneaLithos, Vol. 78, 3, Nov. pp. 263-290.IndiaDharwar Craton, crust-mantle transition
DS2000-0617
2000
Markwick, A.J.W.Markwick, A.J.W., Downes, H.Lower crustal granulite xenoliths from the Arkangelsk kimberlite pipes, petrological, geochemical, geophysicsLithos, Vol. 51, No. 1-2, pp. 135-Russia, Kola Peninsula, ArkangelskXenoliths
DS201902-0295
2019
Markwick, P.J.Markwick, P.J.Palaeogeography in exploration.Geological Magazine, Vol. 156, 2, pp. 366-407.Globalpaleogeography

Abstract: Palaeogeography is the representation of the past surface of the Earth. It provides the spatial context for investigating how the Earth evolves through time, how complex processes interact and the juxtaposition of spatial information. In hydrocarbon exploration, palaeogeographies have been used to map and investigate the juxtaposition, distribution and quality of play elements (source, reservoir, seal and trap), as boundary conditions for source-to-sink analysis, climate modelling and lithofacies retrodiction, but most commonly as the backdrop for presentations and montages. This paper demonstrates how palaeogeography has been and can be used within an exploration workflow to help mitigate exploration risk. A comprehensive workflow for building palaeogeographies is described which is designed to provide a standard approach that can be applied to a range of tasks in exploration and academia. This is drawn from an analysis of the history of palaeogeography and how it has been applied to exploration in the past and why. Map applications, resolution and content depend on where in the exploration and production (E&P) cycle the map is used. This is illustrated here through three case studies, from the strategic decisions of global new ventures exploration to the more detailed basin and petroleum analyses of regional asset teams evaluating basins and plays. Through this, the paper also addresses three commonly asked questions: (1) How can I use palaeogeography in my workflow? (2) How reliable are the maps? (3) How do I build a palaeogeography?
DS1997-0736
1997
Markwick, S.Markwick, S.Changing nature of political risk.. brief overviewMining Engineering, Vol. 49. No. 8, August p. 10-11, 101GlobalEconomics, country risk, Political risk
DS201510-1784
2015
Markwitz, V.Markwitz, V., Hein, K.A.A., Miller, J.Compilation of West African mineral deposits: spatial distribution and mineral endowment. ( mentions diamonds)Precambrian Research, in press available, 21p.Africa, Mali, Mauritania, Senegal, Burkina Faso, Ghana, Ivory CoastMetallogeny

Abstract: The West African Craton is highly endowed in minerals, and their spatial and temporal distribution varies from single to multi-phase mineralization events. They are broadly related to three major tectono-metallogenic elements and formed during distinct mineral epochs: (1) In both Archean Shields (Kénéma-Man and Reguibat) and Paleoproterozoic domains (Baoulé-Mossi, Eglab). These are characterized by giant iron ore deposits that formed between ca. 2.5-2.3 Ga, nearly all gold, porphyry copper, lead-zinc and sedimentary manganese ore that developed between 2.2 and 2.1 Ga, and primary diamonds that formed between two intervals at ca. 2.2-2.0 Ga and in the Mesozoic. (2) Across Pan-African and Variscan belts. These are distinguished by major Precambrian IOCG's, copper-gold that formed at ca. 2.1 Ga and approximately 680 Ma, and Neoproterozoic sedimentary iron ore and phosphate deposits. (3) Within intracratonic and coastal basins. These include the development of Cenozoic lateritic bauxites over Mesozoic dolerites, Tertiary/Quaternary mineral sands deposits, oolitic iron ore and sedimentary phosphate deposits. Geological, spatial and temporal correlations using the multi-commodity West African Mineral Deposit Database highlight that gold and non-gold commodities formed in multiple phases. This commenced in the Liberian Orogeny (2.9-2.8 Ga) with the enrichment of iron ore, nickel sulphides, diamonds and gold in the earth's crust. The pre-Eburnean or Tangaean-EoEburnean-Eburnean I Event yielded gold, and the major Eburnean Orogeny yielded gold, iron ore, manganese, diamonds, magmatic nickel sulphides, copper-gold, lead-zinc, and REE minerals. Throughout the Pan-African event sedimentary manganese deposits, lead-zinc, REE minerals, sedimentary phosphates, and again gold were formed. Primary diamonds and magmatic nickel sulphides are related to the break-up of Gondwana, followed by an intense lateritic weathering period that formed bauxite deposits along the craton margin.
DS201512-1940
2015
Markwitz, V.Markwitz, V., Hein, K.A.A., Jessell, M.W., Miller, J.Metallogenic portfolio of the West African Craton. ( mentions kimberlites)Ore Geology Reviews, Oct 28 10.024Africa, West AfricaReguibat shield, Kenema-Man shield

Abstract: The West African Craton hosts major resources of gold, iron ore, aluminium ore, diamonds, phosphates and manganese. This portfolio of ore deposits is linked to the formation of Archean -Paleoproterozoic greenstone belts, Jurassic rifting and extended periods of Mesozoic to Cenozoic weathering and erosion. We give a brief overview of the temporal and spatial distribution patterns of West African ore deposits with emphasis on the main commodity types. The oldest ore forming processes generated major resources in iron ore and gold in the Kénéma -Man and Reguibat Shields during the Neo-Archean. The majority of gold, porphyry copper, lead -zinc and sedimentary manganese deposits formed during the Paleoproterozoic, dominantly within the Baoulé-Mossi domain. At the same time diamond-bearing kimberlites developed in Ghana. Another distinct diamond event has been recognized in the Mesozoic of the Kénéma -Man shield. Isolated occurrences of IOCG's as well as copper -gold and gold formed in Pan-African/Variscan belts. During the Neoproterozoic, the majority of mineralization consists of sedimentary iron ore and phosphate deposits located within intracratonic basins. During the Phanerozoic aluminium ore, phosphates and mineral sands concentrated along the margins of the coastal and intracratonic basins.
DS201604-0618
2016
Markwitz, V.Markwitz, V., Hein, K.A.A., Jessell, M.W., Miller, J.Metallogenic portfolio of the West African craton. Mentions diamonds in S.L.Ore Geology Reviews, in press available 6p.Africa, Sierra LeoneMetallogeny
DS201608-1422
2016
Markwitz, V.Markwitz, V., Hein, K.A.A., Jessell, M.W., Miller, J.Metallogenic portfolio of the West Africa craton. Mentions diamonds in Ghana, Mali and GuineaOre Geology Reviews, Vol. 78, pp. 558-563.Africa, Ghana, Mali, GuineaAlluvials
DS1992-0684
1992
Marlatt, G.G.Hausel, H.D., Marlatt, G.G., Nielson, E.L., Gregory, R.H.Preliminary study of metals and precious stones along the Union Pacific right of way, southern WyomingWyoming Geological Survey Open File Report, No. 92-5, 79pWyomingDiamonds mentioned
DS1860-0562
1887
Marloth, R.Marloth, R.On the Origin of the Diamond Mines of South AfricaPhil. Soc. Sth. Afr. Transactions, Vol. 4, No. 1, PP. 62-65.Africa, South Africa, Griqualand West, TransvaalDiamond Genesis
DS1910-0073
1910
Marloth, R.Marloth, R.Notes on the Origin of Diamonds of German Southwest AfricaSouth African Journal of Science, Vol. 6, PP. 112-113. ALSO: The Mining Journal, Vol. 87, 1909 PP. 3Southwest Africa, NamibiaGeology, Diamond Genesis, Marine Diamond Placers
DS1970-0556
1972
Marlowe, J.Marlowe, J.Cecil Rhodes. the Anatomy of EmpireMason and Lipscomb, N.Y, 304pSouth AfricaBiography
DS1960-0069
1960
Marlowe, J.I.Marlowe, J.I.Diatremes and a Ring Intrusion on the San Carlos Indian Reservation.Arizona Geological Society Digest., Vol. 3, PP. 150-154.United States, Arizona, Colorado Plateau, Rocky MountainsDiatreme
DS1997-0737
1997
Marmo, J.Marmo, J., Vilpas, L., Chernet, T., Nenonen. K.Study of the kimberlitic indicator minerals in Quaternary samples, eastern and northern Finland.Papunen: 4th. Biennial SGA Meeting, pp. 775-777.FinlandDiamond exploration, Geomorphology, till, esker sampling, geochemistry
DS1999-0129
1999
Marmo, J.Chernet, T., Marmo, J., Nissinen, A.Significantly improved recovery of slightly heavy minerals from Quaternary samples using GTK Modified ..Minerals Eng., Vol. 12, No. 12, Dec. pp. 1521-6.FinlandMineral processing - recovery, diamonds, gravity, 3Knelson preconcentrator
DS2002-0932
2002
Marmo, J.S.Lehtonen, M.L., Marmo, J.S.Exploring for kimberlites in glaciated terrains using chromite in Quaternary till - a regional case study from northern Finland.Journal of Geochemical Exploration, Vol. 76, 3, pp. 155-74.FinlandGeochemistry - chomites
DS2003-0790
2003
Marmo, J.S.Lehtonen, M.L., Marmo, J.S.Glacial dispersion study of kimberlitic material in Quaternary till from the Lahtojoki8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractFinlandDeposit - Lahtojoki
DS200412-1110
2003
Marmo, J.S.Lehtonen, M.L., Marmo, J.S.Glacial dispersion study of kimberlitic material in Quaternary till from the Lahtojoki pipe, eastern Finland.8 IKC Program, Session 8, POSTER abstractEurope, FinlandDiamond exploration Deposit - Lahtojoki
DS200512-0616
2005
Marmo, J.S.Lehtonen, M.L., Marmo, J.S., Nissinen, A.J., Johanson, B.S., Pakkanen, L.K.Glacial dispersal studies using indicator minerals and till geochemistry around two eastern FIn land kimberlites.Journal of Geochemical Exploration, Vol. 87, 1, Oct. pp. 19-43.Europe, Finland, FennoscandiaKaavi-Kuopio, Kuhmo, geochemistry, Pipe 7, Karelian
DS1950-0438
1958
Marmo, V.Wilson, N.W., Marmo, V.Geology, Geomorphology and Mineral Occurrences of the Sula Mountains Schist Belt, Sierra Leone.Geological Survey SIERRA LEONE Bulletin., No. 1, 103P.Sierra Leone, West AfricaGeology, Diamonds
DS1960-0274
1962
Marmo, V.Marmo, V.Geology and Mineral Resources of the Kangari Hills Schist Belt.Geological Survey SIERRA LEONE Bulletin., No. 2, 117P.Sierra Leone, West AfricaGeology, Kimberlite, Diamond
DS1990-0988
1990
Marocco, R.Marocco, R., Noblet, C.Sedimentation, tectonism and volcanism relationships in two Andean basinsof southern PeruGeologische Rundschau, Vol. 79, No. 1, pp. 111-120Peruvolcanism, Tectonics
DS1996-0087
1996
Marocco, R.Barragan, R., Baudino, R., Marocco, R.Geodynamic evolution of the Neogene intermontane Chota Basin, northern Andes of EcuadorJournal of South American Earth Sciences, Vol. 9, No. 5/6, pp. 309-320EcuadorTectonics, Chota Basin
DS1996-1040
1996
Marocco, R.Noblet, C., Lavenu, A., Marocco, R.Concept of continuum as opposed to periodic tectonism in the AndesTectonophysics, Vol. 255, No. 1-2, April 20, pp. 65-78Andes, PeruTectonics
DS2003-1412
2003
Marone, F.Van der Meijde, M., Marone, F., Giardini, D., Van Der Lee, S.Seismic evidence for water deep in Earth's upper mantleScience, No. 5625, June 6, p. 1556-57.MantleWater
DS200412-1227
2004
Marone, F.Marone, F., Van der Lee, S., Giardini, D.Three dimensional upper mantle S velocity model for the Eurasia Africa plate boundary region.Geophysical Journal International, Vol. 158, 1, pp.109-130.Africa, EuropeTectonics, geophysics - seismics
DS200412-1228
2004
Marone, F.Marone, F., Van der Meijde, M., Van der Lee, S., Giadini, D.Joint inversion of local, regional and teleseismic dat a for crustal thickness in the Eurasia Africa plate boundary region.Geophysical Journal International, Vol. 154, 2, pp. 499-514.Europe, AsiaGeophysics - seismics, boundary
DS200412-2039
2003
Marone, F.Van der Meijde, M., Marone, F., Giardini, D., Van Der Lee, S.Seismic evidence for water deep in Earth's upper mantle.Science, No. 5625, June 6, p. 1556-57.MantleWater
DS200712-0682
2007
Marone, F.Marone, F., Romanowicz, B.The depth distribution of azimuthal anisotropy in the continental upper mantle.Nature, Vol. 447, 7141, pp. 198-201.MantleGeophysics - seismics
DS200712-0683
2007
Marone, F.Marone, F., Romanowicz, B.Non-linear crustal corrections in high resolution regeional waveform seismic tomography.Geophysical Journal International, Vol. 170, 1, July pp. 460-467.MantleGeophysics - seismics
DS200712-0684
2007
Marone, F.Marone, F., Romanowicz, B.Non-linear crustal corrections in high resolution regeional waveform seismic tomography.Geophysical Journal International, Vol. 170, 1, July pp. 460-467.MantleGeophysics - seismics
DS201608-1428
2016
Marone, F.Nimis, P., Alvaro, M., Nestola, F., Angel, R.J., Marquardt, K., Rustioni, G., Harris, J.W., Marone, F.First evidence of hydrous silicic fluid films around solid inclusions in gem-qualty diamonds.Lithos, Vol. 260, pp. 384-389.Russia, Africa, South AfricaDeposit - Udachnaya, Premier

Abstract: Diamonds form from fluids or melts circulating at depth in the Earth's mantle. Analysis of these fluids is possible if they remain entrapped in the diamond during its growth, but this is rarely observed in gem-quality stones. We provide the first evidence that typical mineral inclusions in gem-quality diamonds from the Siberian and Kaapvaal cratons are surrounded by a thin film of hydrous silicic fluid of maximum thickness 1.5 ?m. The fluid contains Si2O(OH)6, Si(OH)4, and molecular H2O and was identified using confocal micro-Raman spectroscopy and synchrotron-based X-ray tomographic microscopy. As the solid mineral inclusions have both peridotitic and eclogitic affinities and occur in two cratonic regions, our results demonstrate the strong connection between water-rich fluids and the growth of gem-quality lithospheric diamonds. The presence of the fluid films should be taken into account for a proper evaluation of H2O contents in the mantle based on H2O contents in solid inclusions and for a robust assessment of diamond formation pressures based on the residual pressures of the inclusions.
DS201809-2043
2018
Marone, F.Ivarsson, M., Skogby, H., Bengtson, S., Siljestrom, S., Ounchanum, P., Boonsoong, A., Kruachanta, M., Marone, F., Belivanova, V., Holstrom, S.Intricate tunnels in garnets from soils and river sediments in Thailand - possible endolithic microborings.PluS One, Vol. 13, 8, doi:10.1371/journal.pone.0200351Asia, Thailandgarnets

Abstract: Garnets from disparate geographical environments and origins such as oxidized soils and river sediments in Thailand host intricate systems of microsized tunnels that significantly decrease the quality and value of the garnets as gems. The origin of such tunneling has previously been attributed to abiotic processes. Here we present physical and chemical remains of endolithic microorganisms within the tunnels and discuss a probable biological origin of the tunnels. Extensive investigations with synchrotron-radiation X-ray tomographic microscopy (SRXTM) reveal morphological indications of biogenicity that further support a euendolithic interpretation. We suggest that the production of the tunnels was initiated by a combination of abiotic and biological processes, and that at later stages biological processes came to dominate. In environments such as river sediments and oxidized soils garnets are among the few remaining sources of bio-available Fe2+, thus it is likely that microbially mediated boring of the garnets has trophic reasons. Whatever the reason for garnet boring, the tunnel system represents a new endolithic habitat in a hard silicate mineral otherwise known to be resistant to abrasion and chemical attack.
DS201904-0714
2019
Marone, F.Anzolini, C., Nestola, F., Mazzucchelli, M.L., Alvaro, M., Nimis, P., Gianese, A., Morganti, S., Marone, F., Campione, M., Hutchison, M.T., Harris, J.W.Depth of diamond formation obtained from single periclase inclusions. SDD ( Super Deep Diamonds)Geology , Vol. 47, 3, pp. 219-222.South America, Brazil, Guyanadiamond genesis

Abstract: Super-deep diamonds (SDDs) are those that form at depths between ?300 and ?1000 km in Earth’s mantle. They compose only 1% of the entire diamond population but play a pivotal role in geology, as they represent the deepest direct samples from the interior of our planet. Ferropericlase, (Mg,Fe)O, is the most abundant mineral found as inclusions in SDDs and, when associated with low-Ni enstatite, which is interpreted as retrogressed bridgmanite, is considered proof of a lower-mantle origin. As this mineral association in diamond is very rare, the depth of formation of most ferropericlase inclusions remains uncertain. Here we report geobarometric estimates based on both elasticity and elastoplasticity theories for two ferropericlase inclusions, not associated with enstatite, from a single Brazilian diamond. We obtained a minimum depth of entrapment of 15.7 (±2.5) GPa at 1830 (±45) K (?450 [±70] km depth), placing the origin of the diamond-inclusion pairs at least near the upper mantle-transition zone boundary and confirming their super-deep origin. Our analytical approach can be applied to any type of mineral inclusion in diamond and is expected to allow better insights into the depth distribution and origin of SDDs.
DS201905-1063
2019
Marone, F.Nimis, P., Angel, R.J., Alvaro, M., Nestola, F., Harris, J.W., Casati, N., Marone, F.Crystallographic orientations of magnesiochromite inclusions in diamonds: what do they tell us?Contributions to Mineralogy and Petrology, Vol. 174, p. 29- 13p.Russia, Siberiadeposit - Udachnaya

Abstract: We have studied by X-ray diffractometry the crystallographic orientation relationships (CORs) between magnesiochromite (mchr) inclusions and their diamond hosts in gem-quality stones from the mines Udachnaya (Siberian Russia), Damtshaa (Botswana) and Panda (Canada); in total 36 inclusions in 23 diamonds. In nearly half of the cases (n?=?17), [111]mchr is parallel within error to [111]diamond, but the angular misorientation for other crystallographic directions is generally significant. This relationship can be described as a case of rotational statistical COR, in which inclusion and host share a single axis (1 df). The remaining mchr-diamond pairs (n?=?19) have a random COR (2 df). The presence of a rotational statistical COR indicates that the inclusions have physically interacted with the diamond before their final incorporation. Of all possible physical processes that may have influenced mchr orientation, those driven by surface interactions are not considered likely because of the presence of fluid films around the inclusions. Mechanical interaction between euhedral crystals in a fluid-rich environment is therefore proposed as the most likely mechanism to produce the observed rotational COR. In this scenario, neither a rotational nor a random COR can provide information on the relative timing of growth of mchr and diamond. Some multiple, iso-oriented inclusions within single diamonds, however, indicate that mchr was partially dissolved during diamond growth, suggesting a protogenetic origin of these inclusions.
DS201909-2076
2019
Marone, F.Piazzi, M., Morana, M., Coisson, M., Marone, F., Campione, M., Bindi, L., Jones, A.P., Ferrara, E., Alvaro, M.Multi-analytical characterization of Fe-rich magnetic inclusions in diamonds.Diamonds and Related Materials, in press available 36p. PdfAfrica, Ghanadeposit - Akwatia

Abstract: Magnetic mineral inclusions, as iron oxides or sulfides, occur quite rarely in natural diamonds. Nonetheless, they represent a key tool not only to unveil the conditions of formation of host diamonds, but also to get hints about the paleointensity of the geomagnetic field present at times of the Earth's history otherwise not accessible. This possibility is related to their capability to carry a remanent magnetization dependent on their magnetic history. However, comprehensive experimental studies on magnetic inclusions in diamonds have been rarely reported so far. Here we exploit X-ray diffraction, Synchrotron-based X-ray Tomographic Microscopy and Alternating Field Magnetometry to determine the crystallographic, morphological and magnetic properties of ferrimagnetic Fe-oxides entrapped in diamonds coming from Akwatia (Ghana). We exploit the methodology to estimate the natural remanence of the inclusions, associated to the Earth's magnetic field they experienced, and to get insights on the relative time of formation between host and inclusion systems. Furthermore, from the hysteresis loops and First Order Reversal Curves we determine qualitatively the anisotropy, size and domain state configuration of the magnetic grains constituting the inclusions.
DS201910-2292
2019
Marone, F.Piazzi, M., Morana, M., Coisson, M., Marone, F., Campione, M., Bindi, L., Jones, A.P., Ferrara, E., Alvaro, M.Multi-analytical characterization of Fe-rich magnetic inclusions in diamonds. Akwatiaresearchgate.net, June 18, 333866141 12p. PdfAfrica, Ghanadeposit - Akwatia

Abstract: Magnetic mineral inclusions, as iron oxides or sulfides, occur quite rarely in natural diamonds. Nonetheless, they represent a key tool not only to unveil the conditions of formation of host diamonds, but also to get hints about the paleointensity of the geomagnetic field present at times of the Earth's history otherwise not accessible. This possibility is related to their capability to carry a remanent magnetization dependent on their magnetic history. However, comprehensive experimental studies on magnetic inclusions in diamonds have been rarely reported so far. Here we exploit X-ray diffraction, Synchrotron-based X-ray Tomographic Microscopy and Alternating Field Magnetometry to determine the crystallographic, morphological and magnetic properties of ferrimagnetic Fe-oxides entrapped in diamonds coming from Akwatia (Ghana). We exploit the methodology to estimate the natural remanence of the inclusions, associated to the Earth's magnetic field they experienced, and to get insights on the relative time of formation between host and inclusion systems. Furthermore, from the hysteresis loops and First Order Reversal Curves we determine qualitatively the anisotropy, size and domain state configuration of the magnetic grains constituting the inclusions.
DS201912-2768
2019
Marone, F.Alvaro, M., Mazzucchelli, M.L., Angel, R.J., Murri, M., Campmenosi, N., Scambelluri, M., Nestola, F., Korsakov, A., Tomilenko, A.A., Marone, F., Morana, M.Fossil subduction recorded by quartz from the coesite stability field. GeobarometryGeology, in press, 5p. PdfRussia, Yakutiadeposit - Mir

Abstract: Metamorphic rocks are the records of plate tectonic processes whose reconstruction relies on correct estimates of the pressures and temperatures (P-T) experienced by these rocks through time. Unlike chemical geothermobarometry, elastic geobarometry does not rely on chemical equilibrium between minerals, so it has the potential to provide information on overstepping of reaction boundaries and to identify other examples of non-equilibrium behavior in rocks. Here we introduce a method that exploits the anisotropy in elastic properties of minerals to determine the unique P and T of entrapment from a single inclusion in a mineral host. We apply it to preserved quartz inclusions in garnet from eclogite xenoliths hosted in Yakutian kimberlites (Russia). Our results demonstrate that quartz trapped in garnet can be preserved when the rock reaches the stability field of coesite (the high-pressure and high-temperature polymorph of quartz) at 3 GPa and 850 °C. This supports a metamorphic origin for these xenoliths and sheds light on the mechanisms of craton accretion from a subducted crustal protolith. Furthermore, we show that interpreting P and T conditions reached by a rock from the simple phase identification of key inclusion minerals can be misleading.
DS1984-0323
1984
Marot, A.Gruau, G., Martin, H., Leveque, B., Capdevila, R., Marot, A.Rubidium-strontium and Samarium-neodymium (sm-nd) Geochronology of Lower proterozoic Granite Greenstone Terrains in French Guiana, South America.B.r.g.m., IN PRESSSouth America, French GuianaBlank
DS1984-0482
1984
Marot, A.Marot, A., Capdevila, R., Leveque, B., Gruau, G., Martin, G., Cha.Le Synclinorium du Sud de Guyane Francaise: une Ceinture Deroches Vertes D'age Proterozoic Inferieur.Annual DES SCIENCES DE la TERRE, 10TH. SESSION HELD BORDEAU, South America, GuyanaBlank
DS1998-0943
1998
Marotta, A.M.Marotta, A.M., Fernandez, M., Sabadini, P.Mantle uprooting in collisional settingsTectonophysics, Vol. 296, No. 1-2, pp. 31-46.MantleTectonics, Collision
DS2002-1378
2002
Marotta, A.M.Sabadini, R., Marotta, A.M., De Franco, R., Vermeersen, L.L.A.Style of density stratification in the mantle and true polar wander induced by ice loadingJournal of Geophysical Research, Oct. 29, 10.1029/2001JB000889.MantleGeophysics - seismics
DS200512-1097
2005
Marotta, A.M.Tosi, N., Sabadini, R., Marotta, A.M., Vermeersen, L.L.A.Simultaneous inversion for the Earth's mantle viscosity and ice mass imbalance in Antarctica and Greenland.Journal of Geophysical Research, Vol. 110, B7, B07402 10.1029/2004 JB003236Europe, GreenlandMantle dynamics
DS202203-0340
2022
Marotta, G.S.de Moura Almeida, Y., Marotta, G.S., Franca, G.S., Vidotti, R.M., Fuck, R.A.Crustal thickness estimation and tectonic analysis of the Amazonian craton from gravity data.Journal of South American Earth Sciences, Vol. 111, 10p. PdfSouth America, Brazilgeophysics - seismics

Abstract: The crustal thickness in South America has been mostly determined using seismological techniques. However, because these techniques provide point constraint or profile-specific results, the crustal thickness maps become especially dependent on both the number and spatial distribution of seismological stations. In the Amazonian Craton, the extensive forest cover restricts the number of existing stations, not allowing to elaborate a solely seismological crustal thickness model with homogeneous data coverage. Therefore, to overcome this difficulty, this work proposes a crustal thickness model for the Amazonian Craton developed based on the Parker-Oldenburg method and the Global Geopotential Model called GECO, considering the relationships between wavelengths and depths of the investigation sources. Furthermore, the developed iterative process allowed to determine the average depth of the crust-mantle interface, the density contrast at the interface, and the minimum and maximum frequencies used in the signal filtering process, making the model more robust for defining the used constants. The average crustal thickness of the Amazonian Craton was estimated as 40.25 km, with a standard deviation of the differences of 4.91 km, compared to crustal thickness defined by the seismological data. The estimated model shows great consistency with the data set used while allowing important inferences about craton compartmentation. Also, the geological provinces displayed an N-S connecting trend under the Amazonas, Solimões, and Acre basins, correlating the Guyana Shield with the Central Brazil Shield. Additionally, we observed various tectonic cycles acting on the craton while significantly modifying the structure of the provinces, possibly removing cratonic roots and rejuvenating the crust in older provinces.
DS1991-1529
1991
Marple, R.T.Schweig, E.S.III, Marple, R.T.Bootheel lineament: a possible coseismic fault of the great New MadridearthquakeGeology, Vol. 19, No. 10, October pp. 1025-1028Arkansas, Kentucky, Missouri, TennesseeMidcontinent, Rifting, tectonics
DS1992-1000
1992
Marple, R.T.Marple, R.T., Schweig, E.S. III.Remote sensing of alluvial terrain in a humid, tectonically active setting:the New Madrid seismic zonePhotogrammetric Eng. and Remote Sensing, Vol. 58, No. 2, February pp. 209-219GlobalRemote sensing, Midcontinent tectonics
DS201312-0540
2013
Marquardt, H.Lin, J-F., Speciale, S., Mao, Z., Marquardt, H.Effects of the electronic spin transitions of iron in lower mantle minerals: implications for deep mantle geophysics and geochemistry.Reviews of Geophysics, Vol. 51, 2, pp. 244-275.MantleMineralogy
DS201505-0255
2015
Marquardt, H.Marquardt, H., Miyagi, L.Slab stagnation in the shallow mantle linked to an increase in mantle viscosity.Nature Geoscience, Vol. 8, pp. 311-314.MantleSubduction
DS201809-2003
2018
Marquardt, H.Buchen, J., Marquardt, H., Speziale, S., Kawazoe, T., Ballaran, T.B., Kumosov, A.High pressure single crystal elasticity of wadlsleyite and the seismic signature of water on the shallow transition zone.Earth and Planetary Science Letters, Vol. 498, pp. 77-87.Mantlegeophysics - seismic

Abstract: Earth's transition zone at depths between 410 km and 660 km plays a key role in Earth's deep water cycle since large amounts of hydrogen can be stored in the nominally anhydrous minerals wadsleyite and ringwoodite, . Previous mineral physics experiments on iron-free wadsleyite proposed low seismic velocities as an indicative feature for hydration in the transition zone. Here we report simultaneous sound wave velocity and density measurements on iron-bearing wadsleyite single crystals with 0.24 wt-% . By comparison with earlier studies, we show that pressure suppresses the velocity reduction caused by higher degrees of hydration in iron-bearing wadsleyite, ultimately leading to a velocity cross-over for both P-waves and S-waves. Modeling based on our experimental results shows that wave speed variations within the transition zone as well as velocity jumps at the 410-km seismic discontinuity, both of which have been used in previous work to detect mantle hydration, are poor water sensors. Instead, the impedance contrast across the 410-km seismic discontinuity that is reduced in the presence of water can serve as a more robust indicator for hydrated parts of the transition zone.
DS201809-2083
2018
Marquardt, H.Schulze, K., Marquardt, H., Kawazoe, T., Boallaran, T.B., McCammon, C., Koch-Muller, M., Kurnosov, A., Marquardt, K.Seismically invisable water in Earth's transition zone?Earth and Planetary Science Letters, Vol. 498, pp. 9-16.Mantlewater

Abstract: Ringwoodite, the dominant mineral at depths between 520 km and 660 km, can store up to 2-3 wt.% of water in its crystal structure, making the Earth's transition zone a plausible water reservoir that plays a central role in Earth's deep water cycle. Experiments show that hydration of ringwoodite significantly reduces elastic wave velocities at room pressure, but the effect of pressure remains poorly constrained. Here, a novel experimental setup enables a direct quantification of the effect of hydration on ringwoodite single-crystal elasticity and density at pressures of the Earth's transition zone and high temperatures. Our data show that the hydration-induced reduction of seismic velocities almost vanishes at conditions of the transition zone. Seismic data thus agree with a wide range of water contents in the transition zone.
DS202009-1635
2020
Marquardt, H.Koemets, I., Satta, N., Marquardt, H., Kiseeva, E.S., Kurnosov, A., Stachel, T., Harris, J.W., Dubrovinsky, L.Elastic properties of majorite garnet inclusions in diamonds and the seismic signature of pyroxenites in the Earth's upper mantle.American Mineralogist, Vol. 105, pp. 984-991. pdfMantlediamond inclusions

Abstract: Majoritic garnet has been predicted to be a major component of peridotite and eclogite in Earth's deep upper mantle (>250 km) and transition zone. The investigation of mineral inclusions in diamond confirms this prediction, but there is reported evidence of other majorite-bearing lithologies, intermediate between peridotitic and eclogitic, present in the mantle transition zone. If these lithologies are derived from olivine-free pyroxenites, then at mantle transition zone pressures majorite may form monomineralic or almost monomineralic garnetite layers. Since majoritic garnet is presumably the seismically fastest major phase in the lowermost upper mantle, the existence of such majorite layers might produce a detectable seismic signature. However, a test of this hypothesis is hampered by the absence of sound wave velocity measurements of majoritic garnets with relevant chemical compositions, since previous measurements have been mostly limited to synthetic majorite samples with relatively simple compositions. In an attempt to evaluate the seismic signature of a pyroxenitic garnet layer, we measured the sound wave velocities of three natural majoritic garnet inclusions in diamond by Brillouin spectroscopy at ambient conditions. The chosen natural garnets derive from depths between 220 and 470 km and are plausible candidates to have formed at the interface between peridotite and carbonated eclogite. They contain elevated amounts (12-30%) of ferric iron, possibly produced during redox reactions that form diamond from carbonate. Based on our data, we model the velocity and seismic impedance contrasts between a possible pyroxenitic garnet layer and the surrounding peridotitic mantle. For a mineral assemblage that would be stable at a depth of 350 km, the median formation depth of our samples, we found velocities in pyroxenite at ambient conditions to be higher by 1.9(6)% for shear waves and 3.3(5)% for compressional waves compared to peridotite (numbers in parentheses refer to uncertainties in the last given digit), and by 1.3(13)% for shear waves and 2.4(10)% for compressional waves compared to eclogite. As a result of increased density in the pyroxenitic layer, expected seismic impedance contrasts across the interface between the monomineralic majorite layer and the adjacent rocks are about 5-6% at the majorite-eclogite-interface and 10-12% at the majoriteperidotite-boundary. Given a large enough thickness of the garnetite layer, velocity and impedance differences of this magnitude could become seismologically detectable.
DS202204-0523
2022
Marquardt, H.Immoor, J., Miyagi, L., Liermann, H-P., Speziale, S., Schulkze, K., Buchen, J., Kurnosov, A., Marquardt, H.Weak cubic CaSi0s perovskite in the Earth's mantle.Nature , Vol. 603, pp. 276-279. 10.1038/s41586-021-04378-2Mantleperovskite

Abstract: Cubic CaSiO3 perovskite is a major phase in subducted oceanic crust, where it forms at a depth of about 550 kilometres from majoritic garnet1,2,28. However, its rheological properties at temperatures and pressures typical of the lower mantle are poorly known. Here we measured the plastic strength of cubic CaSiO3 perovskite at pressure and temperature conditions typical for a subducting slab up to a depth of about 1,200 kilometres. In contrast to tetragonal CaSiO3, previously investigated at room temperature3,4, we find that cubic CaSiO3 perovskite is a comparably weak phase at the temperatures of the lower mantle. We find that its strength and viscosity are substantially lower than that of bridgmanite and ferropericlase, possibly making cubic CaSiO3 perovskite the weakest lower-mantle phase. Our findings suggest that cubic CaSiO3 perovskite governs the dynamics of subducting slabs. Weak CaSiO3 perovskite further provides a mechanism to separate subducted oceanic crust from the underlying mantle. Depending on the depth of the separation, basaltic crust could accumulate at the boundary between the upper and lower mantle, where cubic CaSiO3 perovskite may contribute to the seismically observed regions of low shear-wave velocities in the uppermost lower mantle5,6, or sink to the core-mantle boundary and explain the seismic anomalies associated with large low-shear-velocity provinces beneath Africa and the Pacific7-9.
DS202205-0689
2022
Marquardt, H.Immoor, J., Miyagi, L., Liemann, H-P., Speciale, S., Schulze, K., Buchen, J., Kumosov, A., Marquardt, H.Weak cubic CaSiO3 perovskite in the Earth's mantle.Nature, Vol. 603, pp. 276-279.Mantlesubduction

Abstract: Cubic CaSiO3 perovskite is a major phase in subducted oceanic crust, where it forms at a depth of about 550?kilometres from majoritic garnet1,2,28. However, its rheological properties at temperatures and pressures typical of the lower mantle are poorly known. Here we measured the plastic strength of cubic CaSiO3 perovskite at pressure and temperature conditions typical for a subducting slab up to a depth of about 1,200?kilometres. In contrast to tetragonal CaSiO3, previously investigated at room temperature3,4, we find that cubic CaSiO3 perovskite is a comparably weak phase at the temperatures of the lower mantle. We find that its strength and viscosity are substantially lower than that of bridgmanite and ferropericlase, possibly making cubic CaSiO3 perovskite the weakest lower-mantle phase. Our findings suggest that cubic CaSiO3 perovskite governs the dynamics of subducting slabs. Weak CaSiO3 perovskite further provides a mechanism to separate subducted oceanic crust from the underlying mantle. Depending on the depth of the separation, basaltic crust could accumulate at the boundary between the upper and lower mantle, where cubic CaSiO3 perovskite may contribute to the seismically observed regions of low shear-wave velocities in the uppermost lower mantle5,6, or sink to the core-mantle boundary and explain the seismic anomalies associated with large low-shear-velocity provinces beneath Africa and the Pacific.
DS201608-1428
2016
Marquardt, K.Nimis, P., Alvaro, M., Nestola, F., Angel, R.J., Marquardt, K., Rustioni, G., Harris, J.W., Marone, F.First evidence of hydrous silicic fluid films around solid inclusions in gem-qualty diamonds.Lithos, Vol. 260, pp. 384-389.Russia, Africa, South AfricaDeposit - Udachnaya, Premier

Abstract: Diamonds form from fluids or melts circulating at depth in the Earth's mantle. Analysis of these fluids is possible if they remain entrapped in the diamond during its growth, but this is rarely observed in gem-quality stones. We provide the first evidence that typical mineral inclusions in gem-quality diamonds from the Siberian and Kaapvaal cratons are surrounded by a thin film of hydrous silicic fluid of maximum thickness 1.5 ?m. The fluid contains Si2O(OH)6, Si(OH)4, and molecular H2O and was identified using confocal micro-Raman spectroscopy and synchrotron-based X-ray tomographic microscopy. As the solid mineral inclusions have both peridotitic and eclogitic affinities and occur in two cratonic regions, our results demonstrate the strong connection between water-rich fluids and the growth of gem-quality lithospheric diamonds. The presence of the fluid films should be taken into account for a proper evaluation of H2O contents in the mantle based on H2O contents in solid inclusions and for a robust assessment of diamond formation pressures based on the residual pressures of the inclusions.
DS201608-1430
2016
Marquardt, K.Palot, M., Jacobsen, S.D., Townsend, J.P., Nestols, F., Marquardt, K., Harris, J.W., Stachel, T., McCammon, C.A., Pearson, D.G.Evidence for H2O bearing fluids in the lower mantle from diamond inclusion.Lithos, in press available 27p.South America, BrazilSao Luis

Abstract: In this study, we report the first direct evidence for water-bearing fluids in the uppermost lower mantle from natural ferropericlase crystal contained within a diamond from São Luíz, Brazil. The ferropericlase exhibits exsolution of magnesioferrite, which places the origin of this assemblage in the uppermost part of the lower mantle. The presence of brucite-Mg(OH)2 precipitates in the ferropericlase crystal reflects the later-stage quenching of H2O-bearing fluid likely in the transition zone, which has been trapped during the inclusion process in the lower mantle. Dehydration melting may be one of the key processes involved in transporting water across the boundary between the upper and lower mantle.
DS201611-2135
2016
Marquardt, K.Rudloff-Grund, J., Brenker, F.E., Marquardt, K., Howell, D., Schrieber, A., O'Reilly, S.Y., Griffin, W.L., Kaminsky, F.V.Nitrogen nanoinclusions in milky diamonds from Juin a area, Mato Grosso State, Brazil.Lithos, in press available 34p.South America, Brazil, Mato GrossoDeposit - Juina
DS201804-0719
2018
Marquardt, K.Marquardt, K., Faul, U.H.The structure and composition of olivine grain boundaries: 40 years of studies, status and current developments.Physics and Chemistry of Minerals, Vol. 45, 2, pp. 139-172.Mantleolivines

Abstract: Interfaces in rocks, especially grain boundaries in olivine dominated rocks, have been subject to about 40 years of studies. The grain boundary structure to property relation is fundamental to understand the diverging properties of polycrystalline samples compared to those of single crystals. The number of direct structural observations is small, i.e. in range of 100 micrographs, and the number of measurements of properties directly linked to structural observations is even smaller. Bulk aggregate properties, such as seismic attenuation, rheology and electrical conductivity, are sensitive to grain size, and seem to show influences by grain boundary character distributions. In this context we review previous studies on grain boundary structure and composition and plausible relations to bulk properties. The grain boundary geometry is described using five independent parameters; generally, their structural width ranges between 0.4-1.2 nm and the commonly used 1 nm seems a good approximation. This region of enhanced disorder is often enriched in elements that are incompatible in the perfect crystal lattice. The chemical composition of grain boundaries depends on the bulk rock composition. We determined the 5 parameter grain boundary character distribution (GBCD) for polycrystaline Fo90 and studied structure and chemistry at the nm-scale to extend previous measurements. We find that grain boundary planes close to perpendicular to the crystallographic c-direction dominate the grain boundary network. We conclude that linking grain boundary structure in its full geometric parameter space to variations of bulk rock properties is now possible by GBCD determination using EBSD mapping and statistical analyses.
DS201809-2083
2018
Marquardt, K.Schulze, K., Marquardt, H., Kawazoe, T., Boallaran, T.B., McCammon, C., Koch-Muller, M., Kurnosov, A., Marquardt, K.Seismically invisable water in Earth's transition zone?Earth and Planetary Science Letters, Vol. 498, pp. 9-16.Mantlewater

Abstract: Ringwoodite, the dominant mineral at depths between 520 km and 660 km, can store up to 2-3 wt.% of water in its crystal structure, making the Earth's transition zone a plausible water reservoir that plays a central role in Earth's deep water cycle. Experiments show that hydration of ringwoodite significantly reduces elastic wave velocities at room pressure, but the effect of pressure remains poorly constrained. Here, a novel experimental setup enables a direct quantification of the effect of hydration on ringwoodite single-crystal elasticity and density at pressures of the Earth's transition zone and high temperatures. Our data show that the hydration-induced reduction of seismic velocities almost vanishes at conditions of the transition zone. Seismic data thus agree with a wide range of water contents in the transition zone.
DS202009-1606
2020
Marquardt, K.Anzolini, C., Marquardt, K., Stagno, V., Nestola, F.Evidence for complex iron oxides in the deep mantle from FeNi(Cu) inclusions in superdeep diamondsProceedings of the National Academy of Sciences, pnas.org/cgi/doi.10.1073 /pnas.2004269117 7p. PdfMantlediamond inclusions

Abstract: The recent discovery in high-pressure experiments of compounds stable to 24-26 GPa with Fe4O5, Fe5O6, Fe7O9, and Fe9O11 stoichiometry has raised questions about their existence within the Earth’s mantle. Incorporating both ferric and ferrous iron in their structures, these oxides if present within the Earth could also provide insight into diamond-forming processes at depth in the planet. Here we report the discovery of metallic particles, dominantly of FeNi (Fe0.71Ni0.24Cu0.05), in close spatial relation with nearly pure magnetite grains from a so-called superdeep diamond from the Earth’s mantle. The microstructural relation of magnetite within a ferropericlase (Mg0.60Fe0.40)O matrix suggests exsolution of the former. Taking into account the bulk chemistry reconstructed from the FeNi(Cu) alloy, we propose that it formed by decomposition of a complex metal M oxide (M4O5) with a stoichiometry of (Fe3+2.15Fe2+1.59Ni2+0.17Cu+0.04)? = 3.95O5. We further suggest a possible link between this phase and variably oxidized ferropericlase that is commonly trapped in superdeep diamond. The observation of FeNi(Cu) metal in relation to magnetite exsolved from ferropericlase is interpreted as arising from a multistage process that starts from diamond encapsulation of ferropericlase followed by decompression and cooling under oxidized conditions, leading to the formation of complex oxides such as Fe4O5 that subsequently decompose at shallower P-T conditions.
DS202112-1927
2021
Marquardt, K.Gardes, E., Gilbouin, D., Radiquet, B., David, A., Prellier, W., Marquardt, K.Magnesium transport in olivine mantle: new insights from miniturized study of volume and grain boundary diffusion in Mg2Si04 bi-crystals.Contribution to Mineralogy and Petrology, Vol. 176, 99 16p. PdfMantleolivine

Abstract: We report experimental measurements of volume and grain boundary diffusion of 26Mg in Mg2SiO4 bi-crystals at asthenosphere temperatures as a ground reference for olivine. By analysis of literature and combination with previous data, we provide Arrhenius laws D = D0 exp(- E/RT) at ambient pressure for volume diffusion of Mg in Mg2SiO4 in the intrinsic regime along the three crystallographic axes as well as grain boundary diffusion.
DS202201-0005
2021
Marquardt, K.Beyer, C., Myhill, R., Marquardt, K., McCammon, C.A.A reversed redox gradient in Earth's mantle transition zone.Earth and Planetary Science Letters, Vol. 575, 12p.Mantleredox

Abstract: The Earth's mantle hosts a variety of reduced and oxidized phases, including iron-bearing alloys, diamond, and sulfide and carbonate melts. In the upper mantle, increasing pressure favors the stabilization of reduced iron-bearing phases via disproportionation of ferrous iron into ferric and metallic iron. Pressure-driven disproportionation is thought to continue into the transition zone, based on the extrapolation of experiments conducted at lower pressures. To test this hypothesis, we performed high-temperature and high-pressure experiments on basaltic and peridotitic compositions at pressures of 10 to 20 GPa, buffered at different oxygen fugacities. Under these conditions, majoritic garnet is the dominant ferric-iron bearing phase. We analyze our experimental run products for their ferric iron concentrations with EELS and Mössbauer spectroscopy. Contrary to expectations, results show that at iron saturation, ferric iron content of majorite peaks in the upper transition zone and then decreases between 500 and 650 km depth, destabilizing and resorbing reduced phases. This peak can be explained by decreases in the effective volume of ferrous minerals in transition zone assemblages. We also show that natural diamond-hosted majorite inclusions that equilibrated in the sublithospheric mantle grew from variably reduced fluids. These results are consistent with the idea that these diamonds formed during progressive reduction of an originally carbonatitic melt.
DS2001-1128
2001
Marquart, G.Steinberger, B., Schmeling, H., Marquart, G.Large scale lithospheric stress field and topography induced by global mantle circulation.Earth and Planetary Science Letters, Vol. 186, No. 1, Mar. 15, pp. 75-92.MantleGeophysics, Tectonics, geodynamics
DS2003-1224
2003
Marquart, G.Schmeling, H., Marquart, G., Ruedas, T.Pressure and temperature dependent thermal expansivity and the effect on mantleGeophysical Journal International, No. 154, 1, pp. 224-9.MantleBlank
DS200412-1229
2004
Marquart, G.Marquart, G., Schmeling, H.A dynamic model for the Iceland plume and the north Atlantic based on tomography and gravity data.Geophysical Journal International, Vol. 159, 1, pp. 40-52.Europe, IcelandGeodynamics, tectonics, geophysics - gravity
DS200412-1753
2003
Marquart, G.Schmeling, H., Marquart, G., Ruedas, T.Pressure and temperature dependent thermal expansivity and the effect on mantle convection and surface observables.Geophysical Journal International, No. 154, 1, pp. 224-9.MantleGeothermometry
DS200812-1018
2008
Marquart, G.Schmeling, H., Marquart, G.Crustal accretion and dynamic feedback on mantle melting of a ridge centred plume: the Iceland case.Tectonophysics, Vol. 447, 1-4, pp. 31-52.Europe, IcelandMelting
DS1991-1059
1991
Marquatt, G.Marquatt, G.Finite element modeling of lower crustal flow: a model for crustal thickness variationsJournal of Geophysical Research, Vol. 96, No. B12, November 10, pp. 20, 331-20, 335MantleCrust, Modeling -experimental
DS201712-2725
2017
Marquea, J.C.Rossoni, M.B., Bastos Neto, A.C., Souza, V.S., Marquea, J.C., Dantas, E., Botelho, N.F., Giovannini, A.L., Pereira, V.P.U-Pb zircon geochronological investigation on the Morro dos Seis Lagos carbonatite complex and associated Nb deposit ( Amazonas, Brazil).Journal of South American Earth Sciences, Vol. 80, pp. 1-17.South America, Brazilcarbonatite

Abstract: We present results of U-Pb dating (by MC-ICP-MS) of zircons from samples that cover all of the known lithotypes in the Seis Lagos Carbonatite Complex and associated lateritic mineralization (the Morro dos Seis Lagos Nb deposit). The host rock (gneiss) yielded an age of 1828 ± 09 Ma interpreted as the crystallization time of this unit. The altered feldspar vein in the same gneiss yielded an age of 1839 ± 29 Ma. Carbonatite samples provided 3 groups of ages. The first group comprises inherited zircons with ages compatible with the gneissic host rock: 1819 ± 10 Ma (superior intercept), 1826 ± 5 Ma (concordant age), and 1812 ± 27 Ma (superior intercept), all from the Orosirian. The second and the third group of ages are from the same carbonatite sample: the superior intercept age of 1525 ± 21 Ma (MSWD ¼ 0.77) and the superior intercept age of 1328 ± 58 Ma (MSWD ¼ 1.4). The mineralogical study indicates that the ~1.3 Ga zircons have affinity with carbonatite. It is, however, a tendence rather than a well-defined result. The data allow state that the age of 1328 ± 58 Ma represents the maximum age of the carbonatite. Without the same certainty, we consider that the data suggest that this age may be the carbonatite age, whose emplacement would have been related to the evolution of the K'Mudku belt. The best age obtained in laterite samples (a superior intercept age of 1828 ± 12 Ma) is considered the age of the main source for the inherited zircons related to the gneissic host rock.
DS201912-2821
2019
Marquerno, T.Sanatmaria-Perez, D., Ruiz-Fuertes, J., Pena-Alvarez, M., Chulia-Jordan, R., Marquerno, T., Zimmer, D., Guterrez-Cano, V., Macleod, S., Gregoryanz, E., Popescue, C., Rodriguez-Herandez, P., Munoz, A.Post-tilleyite, a dense calcium silicate carbonate phase.Nature Scientific Reports, Vol. 9, 11p. PdfMantletilleyite

Abstract: Calcium carbonate is a relevant constituent of the Earth’s crust that is transferred into the deep Earth through the subduction process. Its chemical interaction with calcium-rich silicates at high temperatures give rise to the formation of mixed silicate-carbonate minerals, but the structural behavior of these phases under compression is not known. Here we report the existence of a dense polymorph of Ca5(Si2O7)(CO3)2 tilleyite above 8 GPa. We have structurally characterized the two phases at high pressures and temperatures, determined their equations of state and analyzed the evolution of the polyhedral units under compression. This has been possible thanks to the agreement between our powder and single-crystal XRD experiments, Raman spectroscopy measurements and ab-initio simulations. The presence of multiple cation sites, with variable volume and coordination number (6-9) and different polyhedral compressibilities, together with the observation of significant amounts of alumina in compositions of some natural tilleyite assemblages, suggests that post-tilleyite structure has the potential to accommodate cations with different sizes and valencies.
DS2001-1018
2001
Marques, F.O.Sautter, V., Duchene, S., Marques, F.O.New analytical and numerical geospeedometers tested on garnet pyroxenites from Braganca Nappe Complex.Tectonophysics, Vol. 342, No. 1-2, Dec. pp. 39-59.Portugal, northeastGeospeedometry
DS1994-0261
1994
Marques, F.R.V.Cardoso, F.A.C.M., Rosa, J.W.C., Marques, F.R.V.Group velocity of Rayleigh waves in S America, Atlantic and the crustal And upper mantle structure of regions.International Symposium Upper Mantle, Aug. 14-19, 1994, pp. 108-110.BrazilMantle, Geophysics -Rayleigh waves
DS2000-0618
2000
Marques, I.S.Marques, I.S.Mantle sources of the Parana magmatic provinceIgc 30th. Brasil, Aug. abstract only 4p.Brazil, Ponta GrossaMagmatism
DS1993-1242
1993
Marques, J.M.Pinna, P., Jourde, G., Calvez, J.Y., Mroz, J.P., Marques, J.M.The Mozambique Belt in northern Mozambique: Neoproterozoic 1100-850 Macrustal growth and tectogenesis and superimposed Pan-African 800-550 MatectonisM.Precambrian Research, Vol. 62, No. 1-2, April pp. 1-60GlobalTectonics, Mozambique
DS202011-2061
2020
Marques, L.Speciale, S., Censi, P., Gomes, C., Marques, L.Carbonatites from the southern Brazilian platform: a review. II: isotopic evidences.Open Geosciences ( researchgate), 26p. PdfSouth America, Brazilcarbonatite

Abstract: Early and Late Cretaceous alkaline and alkaline-carbonatitic complexes from southern Brazil are located along the main tectonic lineaments of the South America Platform. Calcium-, magnesium-, and ferrocarbonatites are well represented and frequently associated even in the same complex. Primary carbonates present significant variations in C-O isotopic compositions, which are mainly due to isotope exchange with H2O-CO2-rich hydrothermal fluids, whereas fractional crystallization or liquid immiscibility probably affects the ?18O and ?13C values by no more than 2?‰ Our isotope exchange model implies that the most significant isotopic variations took place in a hydrothermal environment, e.g., in the range 400-80°C, involving fluids with the CO2/H2O ratio ranging from 0.8 to 1. Sr-Nd-Pb isotope systematics highlight heterogeneous mixtures between HIMU and EMI mantle components, similar to the associated alkaline rocks and the flood tholeiites from southern Brazil. In spite of the strong variation shown by C-O isotopes, Sr-Nd-Pb-Os isotopic systematics could be related to an isotopically enriched source where the chemical heterogeneities reflect a depleted mantle "metasomatized" by small-volume melts and fluids rich in incompatible elements. These fluids are expected to have promoted crystallization of K-rich phases in the mantle, which produced a veined network variously enriched in LILE and LREE. The newly formed veins (enriched component) and peridotite matrix (depleted component) underwent a different isotopic evolution with time as reflected by the carbonatites. These conclusions may be extended to the whole Paraná-Etendeka system, where isotopically distinct parent magmas were generated following two main enrichment events of the subcontinental lithospheric mantle at 2.0-1.4 and 1.0-0.5?Ga, respectively, as also supported by Re-Os systematics. The mantle sources preserved the isotopic heterogeneities over a long time, suggesting a nonconvective lithospheric mantle beneath different cratons or intercratonic regions. Overall, the data indicate that the alkaline-carbonatitic magmatism originated from a locally heterogeneous subcontinental mantle.
DS1994-1108
1994
Marques, L.S.Marques, L.S., Piccirillo, E.M.What was the role of Tristan da Cunha mantle plume in the Parana flood basalt generation?International Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 49-51.BrazilMagma, Mantle plume
DS200712-0912
2007
Marques, L.S.Rosset, A., De Min, A., Marques, L.S., Macambira, M.J.B., Ernesto, M., Renne, P.R., Piccrillo, E.M.Genesis and geodynamic significance of Mesoproterozoic and Early Cretaceous tholeiitic dyke swarms from the Sao Francisco Craton, Brazil.Journal of South American Earth Sciences, Vol. 24, 1, June pp. 69-92.South America, BrazilDyke swarms
DS201801-0071
2017
Marques, L.S.Teixeira, W., Oliveira, E.P., Marques, L.S.Nature and evolution of the Archean crust of the Sao Francisco Craton.Heibron, H. et al. eds. Sao Francisco Craton, eastern Brazil, Regional geology reviews., Chapter 3, pdfSouth America, BrazilGeology

Abstract: We overview the Archean tectonic framework the São Francisco craton based on geologic constraints, integrated geochronologic interpretation and isotopic-geochemical evidence of basement rocks. U-Pb provenance studies of Archean and Paleoproterozoic supracrustal sequences are also used to provide additional inferences about the geodynamic scenario. The Archean rocks crop out mainly in two large areas in the southern and northern portions of the craton, surrounded and/or in tectonic contact with Paleoproterozoic orogenic belts. The ancient substratum is essentially composed of medium- to high-grade gneissic-migmatitic rocks including TTG suites and coeval granite-greenstone associations that collectively provide an isotopic record as old as 4.1 Ga. The combined U-Pb and Sm-Nd TDM age peaks coupled with U-Pb inherited ages in detrital zircons from the supracrustal sequences indicate that very ancient continental crust (?3.5 Ga) exist, particularly in the northern portion of the craton. Mesoarchean events are episodic between 3.6-3.3 and 3.2-2.9 Ga, as for the Neoarchean (2.8-2.6 Ga) in both cratonic portions. This isotopic record indicates a protracted Archean history for the São Francisco craton, highlighted by peculiar tectonic-metamorphic histories of the basement rocks. From a tectonic point of view the compiled data concur with a diachronic evolution from Paleo- to Neoarchean times by means of juvenile accretion/differentiation events characterized by multiple TTG plutonism in genetic association with greenstone belts, coupled with partial melting events of earlier-formed material. All ancient basement complexes and/or continental blocks assembled diachronically during the Late Neoarchean by convergence-related processes akin to plate dynamics. Late-tectonic K-rich granitoids, mafic-ultramafic complexes and mafic dikes collectively mark the Neoarchean thickening and final cratonization of the continental crust.
DS200612-0870
2005
Marques, R.Marques, R.Lundas - the stones of death Angola's deadly diamonds. Human rights abuses in the Lunda Provinces, 2004.google.com Lundas - stones of death, March 9, 73p. free downloadAfrica, AngolaHistory - conflict diamonds
DS201507-0324
2015
Marques de Morais, R.Marques de Morais, R.Blood diamonds: torture and corruption in Angola. IN ENGLISH publ originally in Portugal in 2011.Diamonds.net, English translation 156p. Pdf availableAfrica, AngolaBook
DS2001-0406
2001
Marquette, G.Gray, J.T., Gosse, J.C., Marquette, G.Weathering zones in the Torngat Mountains Labrador, ice sheet thickness and basal thermal regime.Geological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p.54, abstract.Quebec, Ungava, LabradorGeomorphology, Laurentide Ice Sheet
DS2001-0238
2001
MarquezDe Ignacio, C., Lopex, I., Oyarzun, MarquezThe northern Patagonia Somuncura plateau basalts: a product of slab induced shallow asthenospheric upwellTerra Nova, Vol. 13, pp. 117-21.Patagonia, South AmericaSubduction, Basalt
DS1993-0956
1993
Marquez, M.Mahlburg Kay, S., Ramos, V.A., Marquez, M.Evidence in Cerro Pampa volcanic rocks for slab melting prior to Ridge-Trench collision in southern South AmericaJournal of Geology, Vol. 101, No. 6, November pp. 703-714Argentina, PatagoniaAdakite flows, Magmatic, melt
DS200612-1025
2006
Marquez, M.Pankhurst, R.J., Rapela, C.W., Fanning, C.M., Marquez, M.Gondwanide continental collision and origin of Patagonia.Earth Science Reviews, Vol. 76, 3-4, June pp. 235-257.South AmericaTectonics
DS1994-1109
1994
Marquez, M.J.Marquez, M.J., et al.Depositos y manifestaciones minerales de la Cordillera Patagonia yFueguinaActas del Encuentro International de Mineria, Vol. 1, pp. 66-83ArgentinaMineral deposits, Overview
DS201906-1351
2019
Marquis, E.Smith, M.P., Estrade, G., Marquis, E., Goodenough, K., Nason, P., Xu, C., Kynicky, J., Borst, A.M., Finch, A.A., Villanova de Benevent, C.Ion adsorption deposits: a comparison of deposits in Madagascar and China.3rd International Critical Metals Meeting held Edinburgh, 1p.abstract p. 53.Africa, Madagascar, ChinaREE

Abstract: Link to presentation pdf.
DS201909-2037
2019
Marquis, E.Estrade, G., Marquis, E., Smith, M., Goodenough, K.,Nason, P.REE concentration processes in ion absorption deposits: evidence from the Ambohimirahavavy alkaline complex in Madagascar.Ore Geology Reviews, in press available, 21p. pdfAfrica, MadagascarREE
DS1994-0799
1994
Marquis, G.Hyndman, R.D., Vanyan, L.L., Marquis, G., Law, L.K.The origin of electrically conductive lower continental crust: saline wateror graphite?Physics of the Earth and Planetary Interiors, Vol. 81, pp. 325-344.MantleGeophysics -magnetotellurics, Graphite, carbon
DS1996-0305
1996
Marquis, R.Cousineau, P.A., Marquis, R.Contrasting fold styles in a volcano-sedimentary successionCanadian Journal of Earth Sciences, Vol. 33, No. 8, August, pp. 1193-1200Quebec, AppalachiaBasin, structure, Basalts
DS1996-0994
1996
Marquis, R.Morin, D., Marquis, R., Jebrak, M.Un diatreme phreatomagmatique montregien dans les Appalaches du QuebecCanadian Journal of Earth Sciences, Vol. 33, No. 5, May pp. 649-655.QuebecGeophysics -magnetics, breccia, Basanite
DS1994-1110
1994
Marr, R.A.Marr, R.A., Baker, D.R., Williams-Jones, A.E.The role of halogens in the speciation of alkali silicate minerals infelsic, peralkaline rocks: an experimental study.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p.GlobalAlkaline rocks, Halogens
DS202012-2234
2020
Marras, G.Mikhailenko, D.S., Stagno, V., Korsakov, A.V., Andreozzi, G.B., Marras, G., Cerantola, V., Malygina, E.V.Redox state determination of eclogite xenoliths from Udachnaya kimberlite pipe ( Siberian craton), with some implications for the graphite/diamond formation.Contributions to Mineralogy and Petrology, Vol. 175, 107, 17p. PdfRussiadeposit - Udachnaya

Abstract: The formation of diamonds within eclogitic rocks has been widely linked to the fate of carbon during subduction and, therefore, referred to conditions of pressure, temperature, and oxygen fugacity (fo2). Mantle-derived eclogite xenoliths from Udachnaya kimberlite pipes represent a unique window to investigate the formation of carbon-free, graphite-diamond-bearing and diamond-bearing rocks from the Siberian craton. With this aim, we exploited oxy-thermobarometers to retrieve information on the P-T-fo2 at which mantle eclogites from the Siberian craton equilibrated along with elemental carbon. The chemical analyses of coupled garnet and omphacitic clinopyroxene were integrated with data on their iron oxidation state, determined both by conventional and synchrotron 57Fe Mössbauer spectroscopy. The calculated fo2s largely vary for each suite of eclogite samples from 0.10 to ? 2.43 log units (?FMQ) for C-free eclogites, from ? 0.01 to ? 2.91 (?FMQ) for graphite-diamond-bearing eclogites, and from ? 2.08 to ? 3.58 log units (?FMQ) for diamond-bearing eclogites. All eclogite samples mostly fall in the fo2 range typical of diamond coexisting with CO2-rich water-bearing melts and gaseous fluids, with diamondiferous eclogites being more reduced at fo2 conditions where circulating fluids can include some methane. When uncertainties on the calculated fo2 are taken into account, all samples essentially fall within the stability field of diamonds coexisting with CO2-bearing melts. Therefore, our results provide evidence of the potential role of CO2-bearing melts as growth medium on the formation of coexisting diamond and graphite in mantle eclogites during subduction of the oceanic crust.
DS1990-0446
1990
Marrett, R.Emerman, S.H., Marrett, R.Why dikes?Geology, Vol. 18, No. 3, March pp. 231-233GlobalDikes, Overview-ductile deformation
DS1991-1060
1991
Marrett, R.Marrett, R., Allmendinger, R.W.Estimates of strain due to brittle faulting: sampling of faultpopulationsJournal of Structural Geology, Vol. 13, No. 6, pp. 735-738GlobalStructure, Sampling -faults
DS1992-1001
1992
Marrett, R.Marrett, R., Emerman, S.H.The relations between faulting and mafic magmatism in the Altiplano Puna Plateau (Central Andes).Earth and Planetary Science Letters, Vol. 112, pp. 53-59.Andes, South AmericaMagmatism, Tectonics
DS1994-1111
1994
Marrett, R.A.Marrett, R.A., et al.Late Cenozoic tectonic evolution of the Puna Plateau adjacent foreland, northwestern Argentine AndesJournal of South American Earth Sciences, Vol. 7, No. 3, April pp. 179-208ArgentinaTectonics
DS1994-0765
1994
Marriner, G.Hergt, J.M., Storey, M., Marriner, G., Tarney, J.Trace element and isotopic compositions of the picritic rocks from CuracaoIsland.International Symposium Upper Mantle, Aug. 14-19, 1994, pp. 94-96.GlobalGeochemistry, Picrites
DS1996-0728
1996
Marriner, G.F.Kerr, A.C., Marriner, G.F., Duncan, R.A.The petrogenesis of Gorgona komatiites, picrites basalts: new field, petrographic and geochem. constraintsLithos, Vol. 37, No. 2/3, April pp. 245-260GlobalKomatiites, Petrography
DS1997-0587
1997
Marriner, G.F.Kerr, A.C., Marriner, G.F., Sinton, C.W.Cretaceous basaltic terranes in western Colombia: elemental chronological and Sr neodymium isotopic constraintsJournal of Petrology, Vol. 38, No. 6, June, pp. 677-702ColombiaPetrogenesis, Basalts
DS200512-0337
2004
Marriner, G.F.Gill, R.C., Aparicio, A., El Azzouzi, M., Hernandez, J., Thirlwall, M.F., Bourgois, J., Marriner, G.F.Depleted arc volcanism in the Alboran Sea and shoshonitic volcanism in Morocco: geochemical and isotopic constraints on Neogene tectonic processes.Lithos, Vol. 78, 4, pp. 363-388.Africa, MoroccoShoshonite
DS202010-1866
2020
Marrocchi, Y.Piani, L., Marrocchi, Y., Rigaudier, T.Earth's water may have been inherited from material similar to enstatite chondrite metorites.Science, Vol. 369, 6507, pp. 110-1113. doi. 10.1126/ science.aba.1948Mantlewater

Abstract: The abundances of Earth's chemical elements and their isotopic ratios can indicate which materials formed Earth. Enstatite chondrite (EC) meteorites provide a good isotopic match for many elements but are expected to contain no water because they formed in the hot inner Solar System. This would require Earth's water to be from a different source, such as comets. Piani et al. measured hydrogen contents and deuterium/hydrogen ratios (D/H) in 13 EC meteorites (see the Perspective by Peslier). They found far more hydrogen than is commonly assumed, with D/H close to that of Earth's mantle. Combining these data with cosmochemical models, they show that most of Earth's water could have formed from hydrogen delivered by EC meteorites.
DS1997-0411
1997
Marrs, R.Gill, C., Marrs, R.Detection of kimberlite pipes in the Colorado - Wyoming State Line District using AVARIS.Twelfth Geologic Remote Sensing, Nov. 17th., AbstractsColorado, WyomingGeophysics - remote sensing, AVARIS
DS1982-0397
1982
Marrs, R.W.Marrs, R.W., Hausel, W.D.Detection of Diamond Bearing Kimberlites in the Colorado Wyoming Kimberlite Province. #1Report Submitted To Nasa/jet Propulsion Laboratory, First Qu, 3P.Colorado, Wyoming, United States, State Line, Rocky MountainsKimberlite, Geophysics, Soil Sampling, Geochemistry
DS1982-0398
1982
Marrs, R.W.Marrs, R.W., Hausel, W.D.Detection of Diamond Bearing Kimberlites in the Colorado Wyoming Kimberlite Province. #2Report Submitted To Nasa/jet Propulsion Laboratory Second Qu, 2P.Colorado, Wyoming, United States, State Line, Rocky MountainsKimberlite, Multispectral Remote Sensing, Geophysics
DS1983-0433
1983
Marrs, R.W.Marks, J.E., Marrs, R.W.Remote Sensing Exploration for Poorly Exposed Kimberlite In the Colorado-Wyoming Region.Geological Survey WYOMING, Publishing INF. Circular No. 19, PP. 11-13.United States, Colorado, Wyoming, State Line, Rocky MountainsLandsat
DS1984-0483
1984
Marrs, R.W.Marrs, R.W.Spectral Detection of KimberliteAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) PREPRINT., No. 84-343, 8P.United States, Wyoming, State Line, Rocky MountainsRemote Sensing
DS1984-0484
1984
Marrs, R.W.Marrs, R.W., Marks, J., Hausel, W.D., Albert, K.G.Detection of Diamond Bearing Kimberlites in the Colorado Wyoming Province. #2Nasa Jet Propulsion Laboratory, Final Report Dated Sept. 28t, 70P.United States, Colorado, Wyoming, State Line, Rocky MountainsRemote Sensing, Geochemistry, Sampling, Prospecting, Geophysics
DS1984-0485
1984
Marrs, R.W.Marrs, R.W., Marks, J.E., Hausel, W.D., Albert, G.K.Detection of Diamond Bearing Kimberlites in the Colorado Wyoming Province. #1International Symposium on Remote Sensing of Environment., THIRD THEMATIC CONFERENCE, APRIL 16TH.-19TH. 11P.United States, State Line, Colorado, WyomingLandsat, Remote Sensing, Geophysics, Analyses, Diatreme
DS1984-0486
1984
Marrs, R.W.Marrs, R.W., Raines, G.L.Tectonic Framework of Powder River Basin, Wyoming and Montana Interpreted from Land sat Imagery.American Association Petrol. Geol., Vol. 68, No. 11, NOVEMBER PP. 1718-1731.United States, Montana, Wyoming, Rocky MountainsTectonics, Remote Sensing, Lineaments, Sedimentation
DS1993-0973
1993
Mars, P.J.Mars, P.J., MacArthur, B.T., Pirie, J.Canadian diamond exploration.. high risk.. high reward. Background-historical and overview of current northwest Territories play to date June 11, 1993.Bunting Warburg Inc. Research Report, June 11, 23p.Northwest TerritoriesNews item, Promotional overview
DS2002-1735
2002
Marschall, H.Woodland, A.B., Seitz, H.M., Altherr, R., Marschall, H., Olker, B., Ludwig, T.Li abundances in eclogite minerals: a clue to a crustal or mantle origin?Contributions to Mineralogy and Petrology, Vol. 143, 5, pp.587-601.MantleEclogites - lithium
DS2002-1736
2002
Marschall, H.Woodland, A.B., Seitz, H.M., Altherr, R., Marschall, H., Olker, B., Ludwig, T.Li abundances in eclogite minerals: a clue to a crustal or mantle origin?Contributions to Mineralogy and Petrology, Vol.143,5, Aug.pp.587-601.MantleMineralogy - ecologite
DS200712-0685
2007
Marschall, H.Marschall, H., Von Strandmann, P.P., Seitz, H-M., Elliott, T.Heavy lithium in subducted slabs.Plates, Plumes, and Paradigms, 1p. abstract p. A625.MantleSubduction
DS200912-0287
2009
Marschall, H.Hawkesworth, C., Storey, C., Dhuime, B., Marschall, H., Pietranik, A., Kemp, T.The generation, evolution and preservation of the continental crust.Goldschmidt Conference 2009, p. A505 Abstract.MantleZircon geochronology
DS200712-0686
2007
Marschall, H.R.Marschall, H.R., Pogge Von Strandemann, P.A.E., Seitz, H-M., Elliott, T., Niu, Y.The lithium isotopic composition of orogenic eclogites and deep subduction zones.Earth and Planetary Science Letters, In press availableMantleSubduction
DS200712-0687
2007
Marschall, H.R.Marschall, H.R., Pogge von Stranmann, P.A.E., Seit, H-M., Elliott, NiuThe lithium isotopic composition of orogenic eclogites and deep subducted slabs.Earth and Planetary Science Letters, Vol. 262, 3-4, Oct. 30, pp. 563-580.MantleSubduction
DS200812-0715
2008
Marschall, H.R.Marschall, H.R., Pogge Von Strandmann, A.E.Li and Mg exchange between eclogite lenses and their host rocks: evidence from isotope profiles.Goldschmidt Conference 2008, Abstract p.A594.TechnologyEclogite
DS200912-0282
2009
Marschall, H.R.Harlov, D.E., Marschall, H.R.Mechanisms of metasomatic reactions.Mineralogy and Petrology, Vol. 95, 3-4, pp. 159-161.MantleMetasomatism
DS201804-0689
2018
Marschall, H.R.Forster, M.W., Prelevic, D., Schmuck, H.R., Buhre, S., Marschall, H.R., Mertz-Kraus, R., Jacob, D.E.Melting phologopite rich MARID: lamproites and the role of alkalis in olivine liquid Ni partioning.Chemical Geology, Vol. 476, 1, pp. 429-440.Technologylamproites

Abstract: In this study, we show how veined lithospheric mantle is involved in the genesis of ultrapotassic magmatism in cratonic settings. We conducted high pressure experiments to simulate vein + wall rock melting within the Earth's lithospheric mantle by reacting assemblages of harzburgite and phlogopite-rich hydrous mantle xenoliths. These comprised a mica-, amphibole-, rutile-, ilmenite-, diopside (MARID) assemblage at 3-5 GPa and 1325-1450 °C. Melting of the MARID assemblages results in infiltration of melt through the harzburgite, leading to its chemical alteration. At 3 and 4 GPa, melts are high in K2O (> 9 wt%) with K2O/Na2O > > 2 comparable to anorogenic lamproites. Higher pressures and temperatures (5 GPa/1450 °C) lead to increasing MgO contents of the melt and to some extent lower K2O contents (5-7 wt%) at equally high K2O/Na2O ratios. Our experiments provide insights into the role of alkalis in nickel-partitioning (DNi) between olivine and ultrapotassic melt. We observe that the high contents of Na, K, and Al are indicative of high DNi values, implying that the melt polymerization is the dominant factor influencing the olivine/melt nickel partitioning. The change of DNi as a function of melt composition results in a pressure independent, empirical geothermometer: Element oxides represent the composition of the glass (in wt%), and DNi is the liquid/olivine Ni-partitioning coefficient. We propose that this geothermometer is applicable to all natural silicate melts that crystallized olivine in a temperature interval between 1000 and 1600 °C. Application to glass-olivine pairs from calc-alkaline settings (Mexico), MORB (East Pacific Rise), and OIB (Hawaii) yielded reasonable values of 996-1199 °C, 1265 °C, and 1330 °C, respectively.
DS201805-0942
2018
Marschall, H.R.Cruz-Uribe, A.M., Marschall, H.R., Gaetani, G.A., Le Roux, V.Generation of alkaline magmas in subduction zones by partial melting of melange diapirs - an experimental study.Geology, Vol. 48, 4, pp. 343-346.Technologysubduction

Abstract: Alkaline lavas occur globally in subduction-related volcanic arcs. Conventional models for the origin of these lavas typically invoke a multi-stage process in which mantle wedge peridotite, enriched in phlogopite and/or amphibole due to prior metasomatism, partially melts during infiltration by fluids and melts derived from subducted oceanic lithosphere. However, geochemical systematics in the majority of subduction-related alkaline lavas require physical mixing of subducted components and peridotite prior to partial melting. This can be explained by the mélange diapir model, which predicts the generation of arc magmas during advection of buoyant material from the slab-wedge interface into the mantle wedge below arcs. Here we report results from experiments in which natural mélange materials were partially melted at upper mantle conditions to produce alkaline magmas. Partial melts produced in our experiments have trace-element abundance patterns that are typical of alkaline arc lavas, such as enrichment in large ion lithophile elements (LILEs) and depletion in Nb and Ta. These results favor generation of alkaline magmas in the arc and backarc regions of subduction zones by partial melting of mélange materials rather than previously metasomatized peridotite.
DS201907-1545
2019
Marschall, H.R.Forster, M.W., Foley, S.F., Marschall, H.R., Alard, O., Buhre, S.Melting of sediments in the deep mantle produces saline fluid inclusions in diamonds.Science Advances, Vol. 5, 5, eaau 2620 7p.Mantlediamond inclusions

Abstract: Diamonds growing in the Earth’s mantle often trap inclusions of fluids that are highly saline in composition. These fluids are thought to emerge from deep in subduction zones and may also be involved in the generation of some of the kimberlite magmas. However, the source of these fluids and the mechanism of their transport into the mantle lithosphere are unresolved. Here, we present experimental results showing that alkali chlorides are stable solid phases in the mantle lithosphere below 110 km. These alkali chlorides are formed by the reaction of subducted marine sediments with peridotite and show identical K/Na ratios to fluid inclusions in diamond. At temperatures >1100°C and low pressures, the chlorides are unstable; here, potassium is accommodated in mica and melt. The reaction of subducted sediments with peridotite explains the occurrence of Mg carbonates and the highly saline fluids found in diamonds and in chlorine-enriched kimberlite magmas.
DS1992-1002
1992
Marschallinger, R.Marschallinger, R.Interface programs to enable full 3-D geological modeling with acombination of Auto CAD and SURFER.Computers and Geosciences, Vol. 17, No. 10, pp. 1383-1394GlobalComputer, Program -AutoCAD, SURFER.
DS1996-0888
1996
Marschallinger, R.Marschallinger, R.A VOXEL visualization and analysis system based on autocadComputers and Geosciences, Vol. 22, No. 4, pp. 379-386GlobalComputer, Program -VOXEL autocad
DS2001-0733
2001
Marschallinger, R.Marschallinger, R., Johnson, S.E.Presenting 3 D models of geological materials on the World Wide WebComputers and Geosciences, Vol. 27, No. 4, pp. 467-76.GlobalComputer - models ?
DS1970-0759
1973
Marsden, .M.A.H.Mcandrew, J., Marsden, .M.A.H.Geomorphology of the Western District Volcanic Plains, Lakes and Coastline.In:regional Guide To Victorian Geology, PP. 100-112.Australia, VictoriaGeomorphology, Lake Ballenmerri, Kimberlite
DS1989-0944
1989
Marsden, D.Marsden, D.Layer cake depth conversionGeophysics: The leading Edge of Exploration, Vol. 8, No. 1, January pp. 10-14GlobalGeophysics, Seismics
DS201605-0877
2016
Marsden, H.Naismith, A., Howell, G., Marsden, H.Design and development of a decline shaft through poorly consolidated Kalahari deposits at Ghaghoo diamond mine.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 1-14.Africa, BotswanaDeposit - Ghaghoo
DS201605-0911
2016
Marsden, H.Tukker, H., Marsden, H., Holder, A., Swarts, B., Van Strijp, T., Grobler, E., Engelbrecht, F.Koffiefontein diamond mine sublevel cave design.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 129-142.Africa, South AfricaDeposit - Koffiefontein
DS2000-0619
2000
Marsella, K.A.Marsella, K.A., Bierman, P., Davis, P.T., Caffee, M.W.Cosmogenic Berylium and Aluminum ages for the last Glacial Maximum eastern Baffin Island, Arctic Canada.Geological Society of America (GSA) Bulletin., Vol. 112, No., Aug., pp. 1296-1312.Northwest Territories, Baffin IslandGeomorphology, Aluminum, Berylium, Geochronology
DS1996-0890
1996
MarshMarsh, McLennanDirectors' and officers liability: an overviewMarsh and McLennan, 20p. (small size pages=10)CanadaLegal, Directorships
DS1988-0440
1988
Marsh, B.D.Marsh, B.D.Crystal capture, sorting and retention in convecting magmaGeological Society of America (GSA) Bulletin, Vol. 100, No. 11, November pp. 1720-1737GlobalLayered intrusion, Magma
DS1989-0945
1989
Marsh, B.D.Marsh, B.D.On convective style and vigor in sheet-like magma chambersJournal of Petrology, Vol. 30, No. 3, June pp. 479-530GlobalLayered intrusion, Tectonics
DS1994-1184
1994
Marsh, B.D.Meyers, J.D., Marsh, B.D.Subduction zone magmatism: a plausible case for slab meltingEos, Vol. 75, No. 16, April 19, p. 352.MantleSubduction
DS1996-0889
1996
Marsh, B.D.Marsh, B.D.Solidification fronts and magmatic evolutionMineralogical Magazine, Vol. 60, No. 1, Feb pp. 5-40GlobalMagmatic processes, Magmatic evolution -fronts
DS1998-0944
1998
Marsh, B.D.Marsh, B.D.On the interpretation of crystal size distributions in magmatic systemsJournal of Petrology, Vol. 39, No. 4, Apr. pp. 553-600GlobalMagma, Crystallinity, characteristics
DS200712-0432
2007
Marsh, B.D.Hersum, T.G., Marsh, B.D.Igneous textures: on the kinetics behind the words.Elements, Vol. 3, 4, August pp. 247-252.TechnologyClassification
DS200712-0688
2006
Marsh, B.D.Marsh, B.D.Dynamics of magmatic systems.Elements, Vol. 2, 5, October pp. 287-292.MantleMagmatism
DS2002-0995
2002
Marsh, E.E.Marsh, E.E., Goldfarb, R.J., Day, W.C.Integrated methods for discovery: global exploration in the twenty first century.abstracts.Society of Economic Geologists, Abstract volume No. 9, 150p.GlobalBook - table of contents
DS1940-0089
1944
Marsh, J.H.Marsh, J.H.Skeleton Coast (1944)Cape Town: Hodder And Stoughton., 120P.Southwest Africa, NamibiaTravelogue, Kimberley
DS1975-0802
1978
Marsh, J.H.Marsh, J.H.Skeleton Coast (1978)Cape Town: Marshes Books, 142P.Southwest Africa, NamibiaTravelogue, Klimlib
DS1970-0753
1973
Marsh, J.S.Marsh, J.S.Alkaline Igneous Rocks of the Coastal Belt South of Luderitz,southwest Africa a Petrological Study.Ph.d. Thesis, University Cape Town., Southwest Africa, NamibiaPetrology
DS1975-0128
1975
Marsh, J.S.Marsh, J.S.The Luderitz Alkaline Province, Southwest Africa. Three ParGeological Society of South Africa Transactions, Vol. 78, No. 2, PP. 215-224.; PP. 225-233.; Vol. 79, No. 2, PSouthwest Africa, NamibiaUltrabasic Alkaline Rocks, Petrology
DS1981-0284
1981
Marsh, J.S.Marsh, J.S., Hawkesworth, C.J., Moore, A.E.Strontium and Neodymium Isotopes in Tertiary Alkaline Volcanics in South western Africa.Geocongress '81 Open Session., ABSTRACT VOLUME, PP. 33-35.South AfricaNamaqualand, Melilitite, Spiegel River, Klaasvoogds, Garies
DS1987-0435
1987
Marsh, J.S.Marsh, J.S.Evolution of a strongly differentiated suite of phonolites from the Klinghardt Mountains, NamibiaLithos, Vol. 20, pp. 41-58NamibiaPetrology, Classification
DS1989-1224
1989
Marsh, J.S.Pirajno, F., Smithies, R.H., Marsh, J.S.An overview of two continental alkaline igneous provinces in NamibiaNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 215 Abstract held June 25-July 1Namibia, Southwest AfricaAlkaline rocks
DS1989-1300
1989
Marsh, J.S.Rogers, N.W., Marsh, J.S.Mantle xenoliths and Archean basalts from South Africa: implications for local heterogeneity in the ArcheanmantleLpi Technical Report, No. 89-05, pp. 75-78South AfricaMantle xenoliths
DS1997-1108
1997
Marsh, J.S.Stiefenhofer, J., Viljoen, K.S., Marsh, J.S.Petrology and geochemistry of the Eldor carbonatite complex LabradorTrough, Quebec.Contrib. Mineralogy and Petrology, Vol. 127, No. 1-2, pp. 147-158.BotswanaGeochemistry, Deposit - Letlhkane
DS1998-1363
1998
Marsh, J.S.Smithlies, R.H., Marsh, J.S.The Marinkas Quellen carbonatite complex; carbonatite magmatism with an uncontaminated depleted mantle...Chemical Geology, Vol. 148, No. 3-4, June 15, pp. 201-212.Namibia, southSignature, continental setting, geochemistry, Deposit - Marinkas Quellen
DS1999-0289
1999
Marsh, J.S.Harris, C., Marsh, J.S., Milner, S.C.Petrology of the alkaline core of the Messum igneous complex, : evidence or the progressively decreasing ...Journal of Petrology, Vol. 40, No. 9, Sept. pp. 1377-98.NamibiaCrustal contamination, Alkaline rocks
DS2003-0877
2003
Marsh, J.S.Marsh, J.S.Review of South African research on volcanic and related rocks and mantle derivedSouth African Journal of Science, Vol. 99, No. 7/8, pp. 381-88.MantlePetrology - technology
DS2003-1289
2003
Marsh, J.S.Skinner, E.M.W., Marsh, J.S.Kimberlite eruption processes8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractSouth AfricaGeology, economics, magmatic, phreatomagmatic, Magmatism
DS200412-1230
2003
Marsh, J.S.Marsh, J.S.Review of South African research on volcanic and related rocks and mantle derived materials 1999-2002.South African Journal of Geology, Vol. 99, no. 7/8, pp. 381-88.MantlePetrology - technology
DS200412-1846
2003
Marsh, J.S.Skinner, E.M.W., Marsh, J.S.Kimberlite eruption processes.8 IKC Program, Session 1, AbstractAfrica, South AfricaGeology, economics, magmatic, phreatomagmatic Magmatism
DS200612-0526
2006
Marsh, J.S.Hanson, E.K., Moore, J.M., Robey, J., Bordy, E.M., Marsh, J.S.Re-estimation of erosion levels in Group I and II kimberlites between Lesotho, Kimberley and Victoria West, South Africa.Emplacement Workshop held September, 5p. extended abstractAfrica, South Africa, LesothoCrustal xenoliths
DS200612-1319
2006
Marsh, J.S.Skinner, E.M.W., Marsh, J.S.The emplacement of class 1 kimberlites - part 2, petrographic evidence.Emplacement Workshop held September, 5p. abstractGlobalTransition zones - root, diatremes, crater
DS200612-1320
2006
Marsh, J.S.Skinner, E.M.W., Marsh, J.S.The emplacement of class 1 kimberlites - part 1, evidence of geological features.Emplacement Workshop held September, 5p. abstractGlobalZones - root, diatremes, crater
DS201012-0266
2009
Marsh, J.S.Hanson, E.K., Moore, J.M., Bordy, E.M., Marsh, J.S., Howarth, G., Robey, J.V.A.Cretaceous erosion in central South Africa: evidence from upper crustal xenoliths in kimberlite diatremes.South African Journal of Geology, Vol. 112, 2, pp. 125-140.Africa, South AfricaGeomorphology
DS1960-0605
1965
Marsh, P.S.Stearns, R.G., Marsh, P.S.Preliminary Conclusions from a Regional Gravity Survey of The Wells Creek Basin Structure, Houston and Stewart Counties.Tennessee Academy of Science Journal, Vol. 40, No. 2, P. 67, (abstract.).GlobalKimberlite, Geophysics
DS1986-0124
1986
Marsh, S.W.Carlson, J.A., Marsh, S.W.Discovery of the George Creek, Colorado kimberlite dikes #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 443-445ColoradoDiamond exploration
DS1987-0088
1987
Marsh, S.W.Carlson, J.A., Marsh, S.W.Discovery of the George Creek, Colorado Kimberlite dikes #2Preprint from author, 26p. 5 figsColoradoUSA, Geophysics
DS1989-0213
1989
Marsh, S.W.Carlson, J.A., Marsh, S.W.Discovery of George Creek, Colorado kimberlite dikesGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1169-78ColoradoExploration history, Geophysics, Geochemistry
DS1990-0511
1990
Marshak, S.Gang Lu, Marshak, S., Kent, D.V.Characteristics of magnetic carriers responsible for Late Paleozoic remagnitization in carbonate strat a of the Mid-continent, USAEarth and Planetary Science Letters, Vol. 99, pp. 351-361MidcontinentGeophysics -remagnetization, Tectonics
DS1992-1003
1992
Marshak, S.Marshak, S., Alkmim, F.F., Jordt-Evangelista, H.Proterozoic crustal extension and the generation of dome and keel structure in an Archean granite-greenstone terraneNature, Vol. 357, No. 6378, June 11, pp. 491-493BrazilTectonics, Greenstone belts
DS1992-1004
1992
Marshak, S.Marshak, S., Wilkerson, M.S.Effect of overburden thickness on thrust belt geometry and developmentTectonics, Vol. 11, No. 3, June pp. 560-566GlobalTectonics, Thrust belt geometry
DS1994-1344
1994
Marshak, S.Paulsen, T., Marshak, S.Cratonic weak zone in the U.S. continental interior: the Dakota-Carolinacorridor.Geology, Vol. 22, No. 1, January pp. 15-18.Missouri, Illinois, Tennessee, Indiana, KentuckyTectonics, Craton
DS1996-0314
1996
Marshak, S.Cunningham, W.D., Marshak, S., Alkmim, F.F.Structural style of basin inversion at mid-crustal levels: two transects in internal zone ...Precambrian Research, Vol. 77, No. 1-2, March 1, pp. 1-16BrazilBrasiliano Aracuai Belt, Structure
DS1996-0891
1996
Marshak, S.Marshak, S., Paulsen, T.Midcontinent United States fault and fold zones: a legacy of Proterozoic intracratonic extensional tectonism?Geology, Vol. 24, No. 2, Feb. pp. 151-154.Midcontinent, ArkansasTectonics, Structure -faults, folds, Rifting
DS1996-0892
1996
Marshak, S.Marshak, S., Paulsen, T.Fault reaction corridors in continental interiors: a reviewGeological Society of America, Abstracts, Vol. 28, No. 7, p. A-446.MidcontinentStructure - fault
DS1997-0738
1997
Marshak, S.Marshak, S., Tinkham, D., et al.Dome and keel provinces formed during Paleoproterozoic orogenic collapse -core complexes, diapirs ???Geology, Vol. 25, No. 5, May pp. 415-418Brazil, Quadrilatero FerriferoPenokean Orogen, Tectonics
DS1998-0020
1998
Marshak, S.Alkim, F.F., Marshak, S.Transamazonian Orogeny in the Southern Sao Francisco Craton region, evidence for Paleoproterozoic ..Precambrian Research, Vol. 90, No. 1-2, June 30, pp. 29-58Brazil, Minas GeraisTectonics, Quadrilatero Ferrifero, Craton
DS1998-0945
1998
Marshak, S.Marshak, S., Hamburger, M., Van der Pluijm, B.Tectonics of continental interiors..... Penrose Conference ReportGsa Today, Vol. 8, No. 2, Feb. pp. 23-24GlobalTectonics, Precambrian
DS1998-0946
1998
Marshak, S.Marshak, S., Hamburger, M., Van der Pluijm, B.A.Tectonics of continental interiors. Penrose Conference reportGsa Today, Vol. 8, No. 2, Feb. pp. 23-24.GlobalContinental interior, Precambrian, Craton
DS200612-0014
2006
Marshak, S.Alkmim, F.F., Marshak, S., Pedrosa Soares, A.C., Peres, G.G., Cruz, S.C., Whittington, A.Kinematic evolution of the Aracuai West Congo in Brazil and Africa: nutcracker tectonics during the Neoproterozoic assembly of Gondwana.Precambrian Research, Vol. 149, 1-2, pp. 43-64.South America, BrazilTectonics - collisional, orogen
DS201706-1095
2017
Marshak, S.Marshak, S., Domrois, S., Abert, C., Larson, T., Pavlis, G., Hamburger, M., Yang, X., Gilbert, H., Chen, C.The basement revealed: tectonic insight from a digital elevation model of the Great Unconformity, USA cratonic platform.Geology, Vol. 45, 5, pp. 391-394.United Statestectonics - Mid continent

Abstract: Across much of North America, the contact between Precambrian basement and Paleozoic strata is the Great Unconformity, a surface that represents a >0.4 b.y.-long hiatus. A digital elevation model (DEM) of this surface visually highlights regional-scale variability in the character of basement topography across the United States cratonic platform. Specifically, it delineates Phanerozoic tectonic domains, each characterized by a distinct structural wavelength (horizontal distance between adjacent highs) and/or structural amplitude (vertical distance between adjacent lows and highs). The largest domain, the Midcontinent domain, includes long-wavelength epeirogenic basins and domes, as well as fault-controlled steps. The pronounced change in land-surface elevation at the Rocky Mountain Front coincides with the western edge of the Midcontinent domain on the basement DEM. In the Rocky Mountain and Colorado Plateau domains, west of the Rocky Mountain Front, structural wavelength is significantly shorter and structural amplitude significantly higher than in the Midcontinent domain. The Bordering Basins domain outlines the southern and eastern edges of the Midcontinent domain. As emphasized by the basement DEM, several kilometers of structural relief occur across the boundary between these two domains, even though this boundary does not stand out on ground-surface topography. A plot of epicenters on the basement DEM supports models associating intraplate seismicity with the Midcontinent domain edge. Notably, certain changes in crustal thickness also coincide with distinct changes in basement depth.
DS201712-2679
2018
Marshak, S.Chen, C., Hersh, G., Fischer, K.M., Andronicos, C.L., Pavlis, G.L., Hamburger, M.W., Marshak, S., Larson, T., Yang, X.Lithospheric discontinuities beneath the U.S. Midcontinent - signatures of Proterozoic terrane accretion and failed rifting.Earth and Planetary Science Letters, Vol. 481, pp. 223-235.United States, Illinois, Indiana, Kentuckygeophysics - seismics Reelfoot Rift

Abstract: Seismic discontinuities between the Moho and the inferred lithosphere-asthenosphere boundary (LAB) are known as mid-lithospheric discontinuities (MLDs) and have been ascribed to a variety of phenomena that are critical to understanding lithospheric growth and evolution. In this study, we used S-to-P converted waves recorded by the USArray Transportable Array and the OIINK (Ozarks-Illinois-Indiana-Kentucky) Flexible Array to investigate lithospheric structure beneath the central U.S. This region, a portion of North America's cratonic platform, provides an opportunity to explore how terrane accretion, cratonization, and subsequent rifting may have influenced lithospheric structure. The 3D common conversion point (CCP) volume produced by stacking back-projected Sp receiver functions reveals a general absence of negative converted phases at the depths of the LAB across much of the central U.S. This observation suggests a gradual velocity decrease between the lithosphere and asthenosphere. Within the lithosphere, the CCP stacks display negative arrivals at depths between 65 km and 125 km. We interpret these as MLDs resulting from the top of a layer of crystallized melts (sill-like igneous intrusions) or otherwise chemically modified lithosphere that is enriched in water and/or hydrous minerals. Chemical modification in this manner would cause a weak layer in the lithosphere that marks the MLDs. The depth and amplitude of negative MLD phases vary significantly both within and between the physiographic provinces of the midcontinent. Double, or overlapping, MLDs can be seen along Precambrian terrane boundaries and appear to result from stacked or imbricated lithospheric blocks. A prominent negative Sp phase can be clearly identified at 80 km depth within the Reelfoot Rift. This arrival aligns with the top of a zone of low shear-wave velocities, which suggests that it marks an unusually shallow seismic LAB for the midcontinent. This boundary would correspond to the top of a region of mechanically and chemically rejuvenated mantle that was likely emplaced during late Precambrian/early Cambrian rifting. These observations suggest that the lithospheric structure beneath the Reelfoot Rift may be an example of a global phenomenon in which MLDs act as weak zones that facilitate the removal of cratonic lithosphere that lies beneath.
DS2001-0013
2001
Marshal\k, S.Alkmim, F.F., Marshal\k, S., Fonseca, M.A.Assembling West Gondwana in the Neoproterozoic: clues from the Sao Francisco craton region, Brasil.Geology, Vol. 29, No. 4, Apr. pp.319-22.BrazilGondwana, tectonics, Brasiliano orogeny, Craton
DS1994-0650
1994
Marshall, B.Graham, I.T., Franklin, B.J., Marshall, B.Evidence and timing of remobilization in upper mantle peridotiteGeological Society of Australia Abstract Volume, No. 37, pp. 143.MantlePeridotite
DS1998-0930
1998
Marshall, B.Mancini, F., Papunen, H., Savitoki, S., Marshall, B.EPMA analyses and X-ray single crystal refinements of garnets from Arkangelsk kimberlites, northwest Russia.Petrology, Vol. 6, No. 6, Nov-Dec. pp. 546-554.Russia, Arkangelsk, Kola PeninsulaCrystallography, Garnet morphology
DS1996-0893
1996
Marshall, D.Marshall, D.TernPlot: an Excel spreadsheet for ternary diagramsComputers and Geosciences, Vol. 22, No. 6, pp. 697-700GlobalComputers, Program -TernPlot
DS201512-1939
2015
Marshall, D.Mao, M., Simandl, G.J., Spence, J., Marshall, D.Fluorite trace-element chemistry and its potential as an indicator mineral: evaluation of LA-ICP-MS method.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 251-264.TechnologyRare earths

Abstract: Fluorite (CaF2) belongs to the isometric system, with a cubic, face-centred lattice. Fluorite commonly forms cubes or octahedrons, less commonly dodecahedrons and, rarely, tetrahexahedrons, trapezohedrons, trisoctahedrons, hexoctahedrons, and botyroidal forms. Fluorite is transparent to translucent, and has vitreous luster. It occurs in a variety of colours including purple, green, blue, or yellow, however it can also be colourless, and can exhibit colour zoning, (Staebler et al., 2006). Fluorite from many localities is fl uorescent (Verbeek, 2006). Fluorite density varies from 3.0-3.6 g/cm3, depending to a large extent on inclusions and impurities in the crystal lattice (Staebler et al., 2006), and its hardness is 4 on Mohs scale (Berry et al., 1983). Many single fl uorite crystals display sector zoning, refl ecting preferential substitution and incorporation of trace elements along successive crystal surfaces (Bosce and Rakovan, 2001). The Ca2+ ion in the fl uorite crystal structure can be substituted by Li+, Na+, K+, Mg2+, Mn2+, Fe2+,3+, Zn2+, Sr2+, Y3+, Zr4+, Ba2+, lanthanides ions, Pb2+, Th4+, and U4+ ions (Bailey et al., 1974; Bill and Calas, 1978, Gagnon et al., 2003; Schwinn and Markl, 2005; Xu et al., 2012; Deng et al., 2014). Concentrations of these impurities do not exceed 1% (Deer, 1965) except in yttrofl uorite (Ca,Y)F2-2.33 and cerfl uorite (Ca,Ce)F2-2.33 (Sverdrup, 1968). Fluorite occurs in a variety of rocks, as an accessory and as a gangue mineral in many metalliferous deposits and, in exceptional cases, as the main ore constituent of economic deposits (Simandl, 2009). Good examples of fl uorite mines are Las Cuevas, Encantada-Buenavista (Mexico); St. Lawrence pluton-related veins and the Rock Candy Mine (Canada); El Hamman veins (Morocco) and LeBurc Montroc -Le Moulinal and Trebas deposits (France) as documented by Ruiz et al. (1980), Grogan and Montgomery (1975), González-Partida et al. (2003), Munoz et al. (2005), and Fulton III and Miller (2006). Fluorite also commonly occurs adjacent to or within carbonatites and alkaline complexes (Kogut et al., 1998; Hagni,1999; Alvin et al., 2004; Xu et al., 2004; Salvi and Williams-Jones, 2006); Mississippi Valley-type (MVT) Pb- Zn-F-Ba deposits; F-Ba-(Pb-Zn) veins (Grogan and Bradbury, 1967 and 1968; Baxter et al., 1973; Kesler et al., 1989; Cardellach et al., 2002; Levresse et al., 2006); hydrothermal Fe (±Au, ±Cu) and rare earth element (REE) deposits (Borrok et al., 1998; Andrade et al., 1999; Fourie, 2000); precious metal concentrations (Hill et al., 2000); fl uorite/metal-bearing skarns (Lu et al., 2003); Sn-polymetallic greissen-type deposits (Bettencourt et al., 2005); and zeolitic rocks and uranium deposits (Sheppard and Mumpton, 1984; Cunningham et al., 1998; Min et al., 2005). Ore deposit studies that document the trace element distribution in fl uorite are provided by Möller et al. (1976), Bau et al. (2003), Gagnon et al. (2003), Schwinn and Markl (2005), and Deng et al. (2014). The benchmark paper by Möller et al. (1976) identifi ed variations in the chemical composition of fl uorites according their origin (sedimentary, hydrothermal, or pegmatitic). Recently, Makin et al. (2014) compiled trace-element compositions of fl uorite from MVT, fl uorite-barite veins, peralkaline-related, and carbonatite-related deposits. They showed that fl uorite from MVT and carbonatite deposits can be distinguished through trace element concentrations, and that the REE concentration of fl uorite from veins is largely independent of the composition of the host rock. Based on the physical and chemical properties of fl uorite, its association with a variety of deposit types, and previous studies, it is possible that fl uorite can be used as a proximal indicator mineral to explore for a variety of deposit types. Unfortunately, the compilation by Makin et al. (2014) contained chemical analyses performed at different laboratories using different analytical techniques (including laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), electron microprobe, neutron activation, and ICP-MS), and precision and accuracy varied accordingly. As an orientation survey, herein we present data from fi ve deposits, with two samples from the Rock Candy deposit (British Columbia), and one sample from each of Kootenay Florence (British Columbia), Eaglet (British Columbia), Eldor (Quebec), and Hastie quarry (Illinois) deposits (Table 1). The main objectives of this study are to: 1) assess variations in chemical composition of fl uorite in the samples and deposit types; 2) evaluate relations between analyses made using laser ablation-inductively coupled plasma mass spectrometry on individual grains [LA-ICP-MS(IG)], and those made using laser ablation-inductively coupled plasma mass spectrometry on fused beads [LA-ICP-MS(FB)] and X-ray fl uorescence (XRF); 3) test the use of stoichiometric Ca content as an internal fl uorite standard, such has been done by Gagnon et al. (2003) and Schwinn and Markl, (2005); 4) select the elements that are commonly present in concentrations above the lower limit of detection of LA-ICP-MS and available for constructing discrimination diagrams; 5) consider if our results agree with the preliminary discrimination diagrams of Makin et al. (2014).
DS201811-2573
2015
Marshall, D.Giuliani, G., Branquet, Y., Fallick, A.E., Groat, L.A., Marshall, D.Emerald deposits around the world, their similarities and differences.InColor, December pp. 56-69.Globalemeralds
DS200712-0666
2006
Marshall, D.D.Madsen, J.K., Thorkelson, D.J., Friedman, R.M., Marshall, D.D.Cenozoic to Recent plate configuration in the Pacific Basin: ridge subduction and slab window magmatism in western North America.Geosphere, Vol. 2, pp. 11-34.United States, CanadaSubduction
DS1988-0441
1988
Marshall, D.J.Marshall, D.J., and Mariano, A.N.Cathodoluminescence of geologic materialsUnwin Hyman, Chap. 4, Class I: native elements Diamond pp.37-38, 117GlobalPetrography, Cathodoluminescence
DS1990-0989
1990
Marshall, E.Marshall, E.GE's cool diamonds.. prompt warm wordsScience, Vol. 250, October 5, pp. 25-26GlobalDiamond synthesis, Sietz
DS2002-0996
2002
Marshall, E.Marshall, E.Diamond project Catoca - Government of Republic of Angola. New model of cooperation stabilizes economics.Prospectors and Developers Association of Canada (PDAC) 2002, 1p. abstractAngolaDeposit - Catoca
DS201707-1348
2017
Marshall, E.W.Marshall, E.W., Lassiter, J.C., Barnes, J.D., Luguet, A., Lissner, M.Mantle melt production during the 1.4 Ga Laurentian magmatic event: isotopic constraints from Colorado Plateau mantle xenoliths.Geology, Vol. 45, 6, pp. 519-522.United States, Colorado Plateaumelting - Navajo Volcanics

Abstract: Plutons associated with a 1.4 Ga magmatic event intrude across southwestern Laurentia. The tectonic setting of this major magmatic province is poorly understood. Proposed melting models include anorogenic heating from the mantle, continental arc or transpressive orogeny, and anatexis from radiogenic heat buildup in thickened crust. Re-Os analyses of refractory mantle xenoliths from the Navajo volcanic field (NVF; central Colorado Plateau) yield Re depletion ages of 2.1–1.7 Ga, consistent with the age of the overlying Yavapai and Mazatzal crust. However, new Sm-Nd isotope data from clinopyroxene in peridotite xenoliths from NVF diatremes show a subset of xenoliths that plot on a ca. 1.4 Ga isochron, which likely reflects mantle melt production and isotopic resetting at 1.4 Ga. This suggests that Paleoproterozoic subcontinental lithospheric mantle was involved in the 1.4 Ga magmatic event. Our constraints support a subduction model for the generation of the 1.4 Ga granites but are inconsistent with rifting and anorogenic anatexis models, both of which would require removal of ancient lithosphere.
DS201803-0464
2017
Marshall, E.W.Marshall, E.W., Barnes, J.D., Lassiter, J.C.The role of serpentinite derived fluids in metasomatism of the Colorado Plateau ( USA) lithospheric mantle.Geology, Vol. 45, 12, pp. 1103-1106.United States, Colorado Plateausubduction

Abstract: Subducting serpentinized lithosphere has distinct ?D and ?18O values compared to normal mantle. Slab-derived fluids that infiltrate the mantle wedge can alter its oxygen and hydrogen isotope composition, raising or lowering the ?18O and ?D values depending on the nature of the subducted components. Hydrous minerals in peridotite xenoliths from the Colorado Plateau (southwestern USA) have ?D values (up to ?33‰) much higher than average mantle (?80‰), but similar to ?D values of olivine-hosted melt inclusions within arc basalts, suggesting a slab-derived fluid source. Oxygen isotope ratios of olivine from these xenoliths are similar to average mantle, yet display a strong negative correlation with clinopyroxene Ce/Sm, a proxy of metasomatism. This correlation is most simply explained by metasomatism from fluids derived from the serpentinized portion of the Farallon slab. Although ?18O values of mantle minerals span a narrow range, integration of stable isotope data with other geochemical tracers can provide new constraints on modern and ancient subduction-related processes, potentially providing a method for probing Archean lithospheric mantle for evidence of early subduction.
DS201809-2068
2018
Marshall, E.W.Marshall, E.W., Lassiter, J.C., Banes. J.B.Understanding the (mis) behaviour of water contents in nominally anhydrous mantle minerals.Goldschmidt Conference, 1p. AbstractMantleperidotites

Abstract: The H/C ratio in earth’s exosphere is higher than it is in the source region of primitive basalts, suggesting an enriched carbon reservoir in the mantle[1]. A plausible explanation is that subduction of carbon may have enriched the mantle in recycled carbon over time. Average basaltic crust contains ~ 2 wt.% CO2 [2], and modeling of slab devolatilisation suggests that subducted carbonate may survive to be transported deeper into the mantle [3]. Carbonated oceanic crust should melt in the transition zone along most subduction geotherms due to a deep trough in the carbonated basalt solidus, and mineral inclusions in superdeep diamonds testify to carbonate melt in their formation [4]. Along cool subduction geotherms carbonate may subduct into the lower mantle, potentially enriching the deep mantle in carbon. Here we report on laser-heated diamond anvil cell experiments in the CaO-MgO-SiO2-CO2 and FeO-MgO-SiO2-CO2 systems at lower mantle pressures where we investigate the stability of carbonate in oceanic crust, and test for decarbonation and diamond forming reactions involving carbonate and coexisiting free silica. We find that carbonate reacts with silica to form bridgmanite ± Ca-perovskite + CO2 at pressures in the range of ~50 to 70 GPa. These decarbonation reactions form an impenetrable barrier to subduction of carbonate into the deeper lower mantle, however, slabs may carry solid CO2 (Phase V) into the deeper lower mantle. We also identify reactions where carbonate or CO2 dissociate to form diamond plus oxygen. We suggest that the deep lower mantle may become enriched in carbon in the form of diamond over time due to subduction of carbonate and solid CO2 and its eventual dissociation to form diamond plus oxygen. Release of oxygen during diamond formation may also provide a mechanism for locally oxidizing the deep mantle.
DS201810-2352
2018
Marshall, E.W.Marshall, E.W., Lasiter, J.C., Barnes, J.D.On the (mis) behavior of water in the mantle: controls on nominally anhydrous mineral water content in mantle peridotites.Earth and Planetary Science Letters, Vol. 499, pp. 219-229.United States, Colorado Plateaumetasomatism

Abstract: In magmatic settings, water behaves as an incompatible species and should be depleted during melting and enriched during metasomatism. Previous studies have identified correlations between nominally anhydrous mineral (NAM) water content ([H2O]) and indices of metasomatism or melt extraction, seemingly confirming this behavior in the mantle. However in detail, these correlations are ambiguous and do not reflect robust controls on NAM [H2O]. We measured orthopyroxene (opx) and clinopyroxene (cpx) [H2O] in variably hydrated and metasomatized peridotite xenoliths from the Navajo volcanic field (NVF) that sample the Colorado Plateau subcontinental lithospheric mantle (SCLM), an endmember of SCLM hydration and metasomatism. These xenoliths span a wide range of pyroxene [H2O] (opx from 50 to 588 ppm wt. H2O; cpx from 38 to 581 ppm wt. H2O), but NAM [H2O] does not correlate with either indices of melt depletion or metasomatism. Growth of hydrous minerals suggests higher water activity than in anhydrous peridotites, and therefore hydrous-mineral-bearing xenoliths and anhydrous xenoliths should have different NAM [H2O] and water activities. However, when the two groups are compared no significant differences can be found in either NAM [H2O] or water activity. We propose that the high diffusivity of hydrogen in the mantle allows for equilibration of water activity in the mantle over sub-kilometer length scales over geologic time. Such diffusive equilibration reduces water activity variability and results in the blurring and destruction of correlations between NAM [H2O] and indices of metasomatism or melt extraction. As a result of diffusive equilibration of water, there is a large difference in the variability of concentration between NAM [H2O] (spanning ?2 orders of magnitude) and similarly incompatible elements such as Ce in the same peridotites (spanning ?4 orders of magnitude). This difference in behavior explains why H2O/Ce ratios in mantle peridotites are highly variable relative to those of basalts.
DS1994-1112
1994
Marshall, J.E.A.Marshall, J.E.A.The Falkland Islands: a key element in Gondwana paleogeographyTectonics, Vol. 13, No. 2, April pp. 499-514GlobalGondwana, Strtaigraphy
DS1994-1113
1994
Marshall, J.E.A.Marshall, J.E.A.The Falkland Islands: a key element in Gondwana paleogeographyTectonics, Vol. 13, No. 2, Apr. pp. 499-514.GlobalTectonics, Gondwana
DS1993-1151
1993
Marshall, J.R.Oberbeck, V.R., Marshall, J.R., Aggarwal, H.Impacts, tillites and the breakup of GondwanalandJournal of Geology, Vol. 101, No. 1, January, pp. 1-19Craters, Rifting
DS1993-1152
1993
Marshall, J.R.Oberbeck, V.R., Marshall, J.R., Aggarwal, H.Impacts, tillites and the breakup of GondwanalandJournal of Geology, Vol. 101, No. 1, January pp. 1-19.Tectonics, Rifting
DS1995-0248
1995
Marshall, L.G.Butler, R.F., Richards, D.R., Semepere, T., Marshall, L.G.Paleomagnetic determinations of vertical axis tectonic rotation from Late Cretaceous and Paleoene strataGeology, Vol. 23, No. 9, Sept. pp. 799-802BoliviaStratigraphy, Paleomagnetism
DS2000-0620
2000
Marshall, S.J.Marshall, S.J., Tarasov, L., Clarke, G., Peltier, R.Glaciological reconstruction of the Laurentide Ice Sheet: physical processes and modelling changes.Canadian Journal of Earth Sciences, Vol. 37, No.5, May pp.769-93.Ontario, CanadaGeomorphology
DS1995-1172
1995
Marshall, T.Marshall, T., Baxter-Brown, R.Basic principles of alluvial diamond explorationJournal of Geochemical Exploration, Vol. 52, pp. 277-292.Australia, South AfricaDiamond exploration, Alluvial, placers
DS200512-0688
2004
Marshall, T.Marshall, T.Rooikoppie gravels.Rough Diamond Review, No. 6, Sept.pp.Africa, South AfricaHistory
DS200712-0689
2007
Marshall, T.Marshall, T., Norton, G.The nature of the Ventersdorp alluvial diamond deposits.Diamonds in Kimberley Symposium & Trade Show, Bristow and De Wit held August 23-24, Kimberley, South Africa, GSSA Diamond Workshop CD slides 24Africa, South AfricaGeology, karst, gravels, Klipgat
DS201412-0551
2014
Marshall, T.Marshall, T., Lomberg, K., Other, A.N.The relevance of the (new, updated) SAMCODE to reporting of diamond exploration results, resources and reserves.GSSA Kimberley Diamond Symposium and Trade Show provisional programme, Sept. 11, title onlyGlobalSAMCODE
DS202006-0934
2020
Marshall, T.Marshall, T.GSSA Professional Affairs Portfolio - discussion April 29 and the need to be Professional!GSSA Presentation, https://www.youtube.com /watch?v=Hnwk3lPkMcMGlobalCSR - Professional Development
DS202104-0593
2021
Marshall, T.Marshall, T., Ward, J.D., de Wit, M.C.Alluvial diamond deposits across Africa - a travelogue.Geological Society of South Africa presentation, https://www.youtube.com/watch?v=1tsWuXo6fB4&t=23sAfrica, Lesotho, Cote d'Ivoire, Democratic Republic of Congo, Tanzania, Angola, South Africa, Ghana, Mauritania, Zimbabwe, Namibia, Central African Republic, Cameroon, Swaziland, Mali, Sierra Leone, Liberia, Guineaalluvials
DS1985-0415
1985
Marshall, T.R.Marshall, T.R., Pretorius, D.A.The Alluvial Diamond Fields of the Western Transvaal, Southafrica.Fourth International Kimberlite Conference, 2P. (abstract.) SUBMITTED.South Africa, TransvaalGeotectonics, Structure, Alluvial Placer Deposits
DS1986-0526
1986
Marshall, T.R.Marshall, T.R.The alluvial diamonds of the Western Transvaal South AfricaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 478-480South AfricaDiamond exploration
DS1986-0527
1986
Marshall, T.R.Marshall, T.R.The alluvial diamond fields of the Western TransvaalEconomic Geology Research Unit, Inf. Circular No. 188, 14pSouth AfricaPlacers
DS1987-0436
1987
Marshall, T.R.Marshall, T.R.The origin of the pans of the western Orange Free State- a morphotectonic study of the paleo-kimberley riverEconomic Geology Research Unit, Circular No. 196, 14pSouth AfricaGeomorphology, Tectonics
DS1989-0946
1989
Marshall, T.R.Marshall, T.R.The alluvial diamond fields of the western Transvaal,South Africa: origin of diamonds and gravelsGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1204-1214South AfricaAlluvial/placers
DS1991-1061
1991
Marshall, T.R.Marshall, T.R.The Diamondiferous gravels of the southwestern Transvaal, South AfricaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 254-256South AfricaElluvial, alluvial, colluvial, placers, alluvial diamonds, Geomorphology
DS1994-1114
1994
Marshall, T.R.Marshall, T.R.The Diamondiferous gravels of the southwestern Transvaal, South AfricaProceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 187-201.South AfricaAlluvials, Placers -diamonds
DS2000-0221
2000
Marshall, T.R.De Wit, M.C.J., Marshall, T.R., Partridge, T.C.Fluvial deposits and drainage evolutionIn: The Cenozoic of Southern Africa, pp. 55-72.South AfricaGeomorphology - alluvials, tectonics, gravels
DS201012-0474
2009
Marshall, T.R.Marshall, T.R., Norton, G.A.The nature of the alluvial diamond deposits of the Ventersdorp district, northwest province, South Africa.South African Journal of Geology, Vol. 112, 2, pp. 109-124.Africa, South AfricaAlluvials
DS201212-0444
2012
Marshall, T.R.Marshall, T.R.Evaluation and valuation of alluvial diamond deposits.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractAfrica, South AfricaDeposit - alluvial, placer
DS201312-0576
2013
Marshall, T.R.Marshall, T.R.Resource estimation and valuation of alluvial diamond deposits.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, Special Issue of the Journal of the Geological Society of India,, Vol. 2, pp. 281-288.TechnologyReserves - DCF
DS201412-0552
2013
Marshall, T.R.Marshall, T.R.Resource estimation and valuation of alluvial diamond deposits.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 281-288.Global, AfricaEconomics - alluvials
DS201609-1716
2016
Marshall, T.R.De Wit, M., Bhebhe, Z., Davidson, J., Haggerty, S.E., Hundt, P., Jacob, J., Lynn, M., Marshall, T.R., Skinner, C., Smithson, K., Stiefenhofer, J., Robert, M., Revitt, A., Spaggiari, R., Ward, J.Overview of diamonds resources in Africa.Episodes, Vol. 9, 2, pp. 198-238.AfricaDiamond resources - overview

Abstract: From the discovery of diamonds in South Africa in 1866 until the end of 2013, Africa is estimated to have produced almost 3.2 Bct out of a total global production of 5.03 Bct, or 63.6% of all diamonds that have ever been mined. In 2013 African countries ranked 2nd (Botswana), 3rd (DRC), 6th (Zimbabwe), 7th (Angola), 8th (South Africa), and 9th (Namibia), in terms of carat production and 1st (Botswana), 4th (Namibia), 5th (Angola), 6th (South Africa), 7th (Zimbabwe), and 9th (DRC), in terms of value of the diamonds produced. In 2013 Africa produced 70.6 Mct out of a global total of 130.5 Mct or 54.1%, which was valued at US$ 8.7 billion representing 61.5% of the global value of US$ 14.1 billion.
DS202106-0955
2020
Marshall, T.R.Marshall, T.R.Evaluation of secondary diamond ( and gemstone) deposits according to SAMREC code.saimm.co.za, 6p. PdfAfrica, South Africaalluvials

Abstract: Alluvial diamond and other gemstone deposits have, typically, been exploited by small artisanal operations with little or no geological control. Over the last decade, however, alluvial deposits have become more interesting to larger (often listed), mid-tier companies wishing to benefit from the higher incomes generated by high-quality stones. The difficulties associated with evaluation and valuation of such alluvial diamond/gemstone deposits are widely known but, regrettably, often not widely understood - leading to several misconceptions over what can and cannot be expected from such deposits. Fortunately, there is a reasonably well-established body of knowledge on alluvial diamonds that has resulted in accepted industry-standard practices of how to evaluate these deposits. The 2016 version of the SAMREC Code includes several sections specific to the requirements of secondary diamond and gemstone deposits, both alluvial and marine. Consequently, it is possible to define Diamond/Gemstone Resources in accordance with the major international Committee for Mineral Reserves International Reporting Standards (CRIRSCO) type codes. This paper outlines some of the requirements and some of the pitfalls that need to be appreciated while estimating Diamond/Gemstone Resources and/or Reserves on such deposits.
DS1860-0445
1884
Marshall, W.P.Marshall, W.P.Notes on the Great Kimberley MineMidland Naturalist (birmingham), Vol. 7, PP. 93-98.Africa, South AfricaDiamond mining
DS1995-1178
1995
Marshintsev, V.Mathez, E.A., Fogel, R.A., Hutcheon, I.D., Marshintsev, V.Carbon isotopic composition and origin of SIC from kimberlites of Russia.Geochimica et Cosmochimica Acta, Vol. 59, No. 4, Feb. pp. 781-792.Russia, YakutiaGeochronology
DS1960-0270
1962
Marshintsev, V.K.Lutts, B.G., Marshintsev, V.K.A Xenolith of Garnet Pyroxenite from the Mir Kimberlite PipeAkad. Nauk Sssr Sib. Div. Yakut., No. L4, PP. 307-3LL.RussiaBlank
DS1960-0863
1967
Marshintsev, V.K.Marshintsev, V.K., Shcelchkova, S.G., Zol'nikov, G.V., Voskres.New Dat a on Moissanite from the Yakutian KimberlitesGeologii i Geofiziki, No. 12, PP. 22-31.RussiaBlank
DS1960-0868
1967
Marshintsev, V.K.Nikishov, K.N., Marshintsev, V.K.Intrusive Carbonatites and Their Relation To kimberlites of Yakutia.Perm:, RussiaKimberlite
DS1970-0131
1970
Marshintsev, V.K.Marshintsev, V.K.Discovery of Baddelyite in Kimberlitic Rocks of YakutiaIn: Geology, Petrography And Mineralogy of Magmatic Formatio, PP. 247-253.RussiaBlank
DS1970-0132
1970
Marshintsev, V.K.Marshintsev, V.K., Sukneva, L.S.Scandium in Minerals and Rocks of the Yakutian Kimberlite Bodies.Geochemistry International, Vol. 7, PP. 1048-1050.RussiaBlank
DS1970-0575
1972
Marshintsev, V.K.Nikischov, K.N., Kovalsky, V.V., Marshintsev, V.K.The Alkalic-ultrabasic Rocks ( Alnoites, Kimberlites and Carbonatites) in the Northeast of the Siberian PlatformInternational Geological Congress 24TH. (MONTREAL), MINERALOGY SECTION, PP. 5L-56.RussiaBlank
DS1982-0399
1982
Marshintsev, V.K.Marshintsev, V.K.Inclusions of Cubic Silicon Carbide in Moissanite from Kimberlitic Rocks, a New Occurrence in Nature #2United States Geological Survey (USGS) TRANSLATION., No. 547, 6P.RussiaCrystallography, Inclusion
DS1982-0400
1982
Marshintsev, V.K.Marshintsev, V.K.Inclusions of Cubic Silicon Carbide in Moissanite from Kimberlite Rocks- New Occurrence in Nature #1United States Geological Survey (USGS) TRANSLATION SERIES, No. 547.RussiaBlank
DS1982-0401
1982
Marshintsev, V.K.Marshintsev, V.K., et al.Inclusions of Cubic Silicon Carbide in Moissanite from Kimberlite Rocks - a New Find in Nature.Doklady Academy of Sciences Nauk SSSR., Vol. 262, No. 1, PP. 204-206.RussiaKimberlite
DS1983-0434
1983
Marshintsev, V.K.Marshintsev, V.K., Zayakina, N.V., Leskova, N.V.New Find of Cubic Silicon Carbide, As Inclusions in Moissanite from Kimberlitic Rocks.Doklady Academy of Science USSR, Earth Science Section., Vol. 262, No. 1-6, PP. 163-166.RussiaMineralogy
DS1984-0136
1984
Marshintsev, V.K.Barashkov, Y.P., Marshintsev, V.K.Tendency toward ilmenite crystallization in kimberlites fromYakutia.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR (Russian), Vol. 278, No. 5, pp. 1210-1213RussiaPetrology, Ilmenite
DS1984-0443
1984
Marshintsev, V.K.Lapin, A.V., Marshintsev, V.K.Carbonatites and Kimberlitic Carbonatites.(russian)Geol. Rudn. Mestorozh., (RUS), Vol. 26, No.3, pp. 28-42RussiaCarbonatite, Genesis
DS1984-0487
1984
Marshintsev, V.K.Marshintsev, V.K., Nikishova, L.V., Gotovtsev, V.V.Serpentine Filling the Needle Channels in Olivine of the Udachnaia Vostochnaia Pipe.Doklady Academy of Sciences AKAD. NAUK. SSSR., Vol. 277, No. 3, PP. 697-700.RussiaBlank
DS1986-0099
1986
Marshintsev, V.K.Brahkov, Yu.P., Marshintsev, V.K.Crystallization trends of ilmenite from kimberlites of YakutiaDoklady Academy of Science USSR, Earth Science Section, Vol. 278, No. 1-6, April, pp. 158-161RussiaMineralogy
DS1986-0528
1986
Marshintsev, V.K.Marshintsev, V.K.Vertical heterogeneity of kimberlite bodies of Yakutia.(Russian)Nauka Siberskoe Otd. Novobirsk*(in Russian), 240pRussiaKimberlite, Petrology
DS1986-0529
1986
Marshintsev, V.K.Marshintsev, V.K., Nikishova, L.V., Gotovtsev, V.V.Serpentine filling needle shaped channels in olivine from the Udachnaya east pipeDoklady Academy of Science USSR, Earth Science Section, Vol. 277, March pp. 170-174RussiaUdachnaya, Mineralogy
DS1988-0442
1988
Marshintsev, V.K.Marshintsev, V.K., Barashkov, I.P.Pipe associated veins as a criterion in search for kimberlitepipes.(Russian)Doklady Academy of Sciences Akad. Nauk SSSR, (Russian), Vol. 298, No. 2, pp. 438-441RussiaBlank
DS1989-0073
1989
Marshintsev, V.K.Barahkov, Yu.P., Marshintsev, V.K., Pankov, V.Yu.Solid inclusions in pyrope-almandine garnets from the kimberlite veins associated with the pipeUdachnaya, Yakutia.(Russian)Mineral. Zhurnal. UKR, (Russian), Vol. 11, No. 3, pp. 19-30RussiaGarnets -analyses-inclusions, Deposit -Udachnaya
DS1989-0074
1989
Marshintsev, V.K.Barashkov, Yu.P., Marshintsev, V.K., Pankov, V. Yu.Solid inclusions in pyrope-almandine garnets from kimberlite veins associated with the Udachnaya pipe.(Russian)Mineral. Zhurn., (Russian), Vol. 11, No. 3, pp. 19-30RussiaGarnet inclusions
DS1989-0947
1989
Marshintsev, V.K.Marshintsev, V.K., Barashkov, Yu.P.Identitification of kimberlite pipes from the presence of kimberlite veins around theM.Doklady Academy of Science USSR, Earth Science Section, Vol. 298, No. 1-6, April pp. 119-121RussiaDykes, Kimberlite
DS1989-0948
1989
Marshintsev, V.K.Marshintsev, V.K., Barashkov, Yu.P.Identification of kimberlite pipes from the presence Of kimberlite veins around theM.Doklady Academy of Science USSR, Earth Science Section, Vol. 298, No. 1-6, pp. 119-121RussiaKimberlite veins, Exploration
DS1990-0990
1990
Marshintsev, V.K.Marshintsev, V.K.Natural shallow carbides in kimberlites of YakutiaInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 814-815RussiaKimberlites, Silicon carbides
DS1990-0991
1990
Marshintsev, V.K.Marshintsev, V.K.Nature of silicon carbide in kimberlite rocks of Yakutia.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 3, pp. 17-26RussiaSilicon carbide, Kimberlites
DS1992-1005
1992
Marshintsev, V.K.Marshintsev, V.K.Thallium in natural media of Yakut diamond bearing Province. (Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 324, No. 5, pp. 1128-1130.Russia, YakutiaGeochemistry, ThalliuM.
DS1994-1115
1994
Marshintsev, V.K.Marshintsev, V.K.Primary kimberlite magmaInternational Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts p. 30.RussiaMagma, Kimberlite magma
DS1997-0059
1997
Marshintsev, V.K.Babushkina, S.A., Marshintsev, V.K.Composition of spinel, ilmenite, garnet and diopside inclusions in phlogopite macrocrysts Mir kimberlite.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 467-480.Russia, YakutiaPetrography, Deposit - Mir
DS1984-0135
1984
Marshintsov, V.K.Barashko, I.P., Marshintsov, V.K.The Crystallization Trend of Ilmenite in Yakutian KimberliteDoklady Academy of Sciences AKAD. NAUK SSSR., Vol. 278, No. 5, PP. 1210-1213.RussiaGenesis
DS1986-0050
1986
Marshontsev, V.K.Barashkov, Yu.P., Marshontsev, V.K.Crystallization trends of ilmentite from kimberlites of YakutiaDoklady Academy of Science USSR, Earth Science Section, Vol. 278, No. 1-6, pp. 158-161RussiaMir, Udachnaya, Crystallography
DS201912-2788
2020
Marske, J.Hauri, E.H., Cottrell, E., Kelley, K.A., Tucker, J.M., Shimizu, K., Le Voyer, M., Marske, J., Sall, A.E.Carbon in the convecting mantle. IN: Deep carbon: past to present, Orcutt, Daniel, Dasgupta eds., pp. 237-275.Mantlecarbon

Abstract: This chapter provides a summary of the flux of carbon through various oceanic volcanic centers such as mid-ocean ridges and intraplate settings, as well as what these fluxes indicate about the carbon content of the mantle. By reviewing methods used to measure the carbon geochemistry of basalts and then to estimate fluxes, the chapter provides insight into how mantle melting and melt extraction processes are estimated. The chapter discusses how the flux of carbon compares with other incompatible trace elements and gases. From there, the chapter discusses whether the budget of carbon in the ocean mantle can be explained by primordial carbon or whether carbon recycling is required to balance the budget.
DS1860-0704
1891
Marsters, V.F.Kemp, J.F., Marsters, V.F.The Trap Dikes in the Lake Champlain Valley and the Neighbouring Adirondacks.New York Academy of Sciences Transactions, Vol. 11, PP. 13-23.United States, New YorkGeology, Related Rocks
DS1860-0801
1893
Marsters, V.F.Kemp, J.F., Marsters, V.F.The Trap Dikes of the Lake Champlain RegionUnited States Geological Survey (USGS) Bulletin., No. 107, PP. 11-62.United States, New York, VermontGeology, Related Rocks
DS1860-0900
1895
Marsters, V.F.Marsters, V.F.Camptonite and other Intrusives of Lake MemphremagogAmerican GEOLOGIST., Vol. 16, PP. 25-39.Canada, Quebec, United States, VermontRelated Rocks
DS1860-0901
1895
Marsters, V.F.Marsters, V.F.Comptonite and other Intrusives of Lake MemphremagogAmerican Geologist., Vol. 16, PP. 25-39.United States, New YorkPetrology
DS1985-0416
1985
Marston, K.Marston, K.Where Diamonds Are a Gull's Best Friend #2Indiaqua., No. 40, 1985/1, PP. 13-14.Southwest Africa, NamibiaHistory
DS200812-0400
2008
Mart, J.Geyer, A., Mart, J.The new worldwide collapse caldera database (CCDB): a tool for studying and understanding caldera processes.Journal of Volcanology and Geothermal Research, Vol. 175, 3. August 10, pp. 334-354.MantleCalderas
DS201212-0168
2012
Mart, J.Doronzo, D.M., Mart, J., Sulpizio, R., Dellino, P.Aerodynamics of stratovolcanoes during multiphase processes.Journal of Geophysical Research,, Vol. 117, B1, B01207.MantleVolcanoes
DS200912-0088
2008
Mart, R.W.Burke, K., Khan, S.D., Mart, R.W.Grenville Province and Monteregian carbonatite and nepheline syenite distribution related to rifting, collision and plume passage.Geology, Vol. 36, 12, Dec. pp. 983-986.Canada, QuebecCarbonatite
DS202012-2249
2020
Martayan, G.Schmetzer, K., Martayan, G., Blake, A.R.History of the Chivor emerald mine, part 2 ( 1924-1970): between insolvency and viability.Gems & Gemology, Vol. 56, 2, summer pp. 230-257. pdfSouth America, Columbiadeposit - Chivor

Abstract: The history of the Chivor emerald mine in Colombia is a saga with countless twists and turns, involving parties from across the globe. Indigenous people initially exploited the property, followed by the Spanish in the sixteenth and seventeenth centuries, before abandonment set in for 200 years. The mine was rediscovered by Francisco Restrepo in the 1880s, and ownership over the ensuing decades passed through several Colombian owners and eventually to an American company, the Colombian Emerald Syndicate, Ltd., with an intervening but unsuccessful attempt by a German group organized by Fritz Klein to take control. With the Colombian Emerald Syndicate succumbing to bankruptcy in 1923, the property was sold and then transferred in 1924 to another American firm, the Colombia Emerald Development Corporation. Under the new ownership, stock market speculation played a far more prominent role in the story than actual mining. Nonetheless, periods of more productive mining operations did take place under managers Peter W. Rainier and Russell W. Anderton. Yet these were not enough to prevent the company, renamed Chivor Emerald Mines, Inc. in 1933, from entering insolvency in 1952 and being placed into receivership. Leadership by Willis Frederick Bronkie enabled the firm to regain independence in 1970 and shortly thereafter to be sold in a series of transactions, with Chivor gradually being returned to Colombian interests.
DS202102-0219
2020
Martayan, G.Schmetzer, K., Martayan, G., Ortiz, J.G.History of the Chivor emerald mine, Part 1 ( 1880-1925): from rediscovery to early production. Part 2 listed previouslyGems & Gemology , Vol. 56, 1, pp. 66-109.South America, Colombiaemerald

Abstract: The history of the Chivor emerald mine in Colombia is rife with legend and adventure. The tale traces from early exploitation by indigenous people, to work by the Spanish in the sixteenth and seventeenth centuries, to 200 years of abandonment and jungle overgrowth. The story then picks up with rediscovery near the turn of the twentieth century by the Colombian mining engineer Francisco Restrepo using clues from a historical manuscript. Still the saga continued, with repeated shortages of investment funds driving multiple ownership changes and little progress toward mining the largely inaccessible deposit. The German gem merchant Fritz Klein, in cooperation with Restrepo, pursued limited mining activities with a small number of workers for a few months prior to the outbreak of World War I. After the war, the American company Colombian Emerald Syndicate, Ltd., took ownership, and mining operations resumed under the new leadership. Ownership changed yet again in the 1920s, followed by multiple cycles of expanding and shrinking mining activity, interrupted by completely unproductive periods.
DS1999-0491
1999
MartelMoorhead, J., Beaumier, M., Lefevbre, Bernier, MartelKimberlites, lineaments et rifts crustaux au Quebec #1Quebec Ministere des Ressources naturelles, (in French), MB99-35, approx. 60p.Quebec, Ungava, LabradorKimberlite, Tectonics, structure, fields, lineaments
DS2000-0682
2000
MartelMoorhead, J., Beaumier, M., Lefebvre, Bernier, MartelKimberlites, lineaments et rifts crustaux au Quebec #2Quebec Department of Mines, Report, 69p.QuebecKimberlites, tectonics, lineaments, rifts, Area - overviews
DS202103-0396
2021
Martel, E.Neil, B.J.C., Gibson, H.D., Pehrsson, S.J., Martel, E., Thiessen, E.J., Crowley, J.L.Provenance, stratigraphic and precise depositional age constraints for an outlier of the 1.9 to 1.8 Ga Nonacho Group, Rae craton, Northwest Territories, Canada.Precambrian Research, Vol. 352, 105999, 15p. PdfCanada, Northwest Territoriesgeochronology

Abstract: The Nonacho Group comprises six formations of continental clastic rocks that were deposited between 1.91 and 1.83?Ga. The Nonacho Group is part of a broader assemblage of conglomerate and sandstone that was deposited atop the Rae craton in response to the amalgamation of Laurentia and supercontinent Nuna, but the details of its tectonic setting are contentious. This paper documents an outlier of Nonacho Group rocks ?50?km east of the main Nonacho basin. Field observations and LA-ICPMS (laser ablation inductively coupled plasma mass spectrometry) U-Pb detrital zircon geochronology are integrated with previous studies of the main basin to better understand the group’s depositional history, provenance and tectonic setting. The lithology and detrital zircon age spectra of the outlier allow for its correlation to the upper two formations of the Nonacho Group. CA-ID-TIMS (chemical abrasion isotope dilution thermal ionization mass spectrometry) analyses of two fragments of the youngest detrital zircon provide a maximum depositional age of 1901.0?±?0.9?Ma. A felsic volcanic cobble dated at ca. 2.38?Ga provides evidence of volcanism during the Arrowsmith orogeny. Detrital zircon dates recovered from the outlier (ca. 3.4-3.0, 2.7, 2.5-2.3 and 2.0-1.9?Ga) are consistent with derivation from topography of the Taltson and/or Thelon orogens on the western margin of the Rae craton. Taltson-Thelon (2.0 to 1.9?Ga) aged detritus is only abundant in the upper two formations of the Nonacho Group, marking a change in provenance from the lower formations. This change in provenance may have coincided with a period of renewed uplift and the unroofing of Taltson-Thelon plutons. The detrital zircon provenance and depositional age of the Nonacho Group is consistent with models that link its deposition to the Taltson and/or Thelon orogens. However, tectonism associated with the 1.9 to 1.8?Ga Snowbird and Trans-Hudson orogens to the east could also have affected basin formation or the change in provenance from the lower to upper Nonacho Group. This study highlights the importance of CA-ID-TIMS in establishing accurate and precise maximum depositional ages for sedimentary successions.
DS202103-0402
2021
Martel, E.Regis, D., Pehrsson, S., Martel, E., Thiessen, E., Peterson, T., Kellett, D.Post - 1.9 Ga evolution of the south Rae craton ( Northwest Territories), Canada: a paleoproterozoic orogenic collapse system.Precambrian Research, Vol. 355, 106105, 29p. PdfCanada, Northwest Territoriessunduction

Abstract: The Trans-Hudson Orogen (THO), formed from the convergence between the Superior craton and the composite Churchill Upper Plate (CUP), is one of the best-preserved examples of a collisional orogen in the Paleoproterozoic. Similar to modern collision systems such as the Himalayan orogen, it is characterized by a composite upper plate in which terrane accretion established a continental plateau that was tectonically and magmatically active for >100 myr. Our study presents new petrological and geochronological data for four samples collected in three lithotectonic domains of the south Rae craton (one of the CUP terranes). The results presented here allow us to re-define the previously proposed extent of THO reworking in the CUP and afford the opportunity to study and compare the evolution of various fragments that illustrate differing levels of a collapsed plateau in the CUP hinterland. The new data indicate that the south Rae craton locally preserves evidence for burial at 1.855-1.84 Ga with peak metamorphic conditions at approximately 790 °C and 9.5-12.5 kbar followed by rapid cooling and decompression melting (P < 6 kbar) at ca. 1.835-1.826 Ga. These results, which provide important and so far missing Pressure-Temperature-time (P-T-t) constraints on the evolution of the south Rae craton in the Northwest Territories at Trans-Hudson time, coupled with existing regional geochronological and geochemical data, are used to propose an updated model for the post-1.9 Ga THO collision and extensional collapse. Our results reveal that: i) initial thickening in the upper plate started at Snowbird time (ca. 1.94 Ga), then continued via Sask collision (with high-grade metamorphism recorded in the south Rae craton, ca. 1.85 Ga), and ended with Superior collision (ca. 1.83 Ga); ii) the extent of the THO structural and metamorphic overprint in the SW CUP is much broader across strike than previously recognized, and iii) T-t data in the south Rae are indicative of relatively fast cooling rates (8-25 °C/Ma) compared to other known Precambrian orogens. We suggest that the Paleoproterozoic THO represents the first record of a major ‘modern-style’ orogenic plateau collapse in Earth’s history.
DS1993-0136
1993
Martel, J-J.Borduas, B., Martel, J-J.The Le Tac Township kimberlite discoveryQuebec Exploration Conference summaries held September 15-1th. Val d'Or, pp. 13-16QuebecLe Tac Township
DS2002-0753
2002
Martel, S.J.Ito, G., Martel, S.J.Focusing of magma in the upper mantle through dike interactionJournal of Geophysical Research, Oct. 29, 10.1029/2001JB000251.MantleMagmatism
DS2002-0754
2002
Martel, S.J.Ito, G., Martel, S.J.Focusing of magma in the upper mantle through dike interactionJournal of Geophysical Research, Vol. 107, 10, ECV 6 DOI 10.1029/2001JB000251MantleMagmatism - not specific to diamonds
DS2000-0621
2000
Martelat, J.E.Martelat, J.E., Lardeaux, J.M., Rakotondrazafy, R.Strain pattern and late Precambrian deformation history in southern MadagascarPrecambrian Research, Vol. 102, No. 1-2, July 1, pp. 1-20.MadagascarTectonics
DS202007-1162
2020
Martelat, J-E.Martelat, J-E., Cardon, H., Lardeaux, J-M., Nicollet, C., Schulmann, K., Pili, E.Geophysical evidence for large scale mullion type structures at the mantle crust interface in southern Madagascar: implications for Neoproterozoic orogeny.International Journal of Earth Science, Vol. 109, 4, pp. 1487-1500.Africa, Madagascartectonics

Abstract: This study uses gravimetric data integrated with recent seismic data published on south Madagascar to investigate geometry of crust-mantle interface. The regional tectonic framework of Madagascar is characterised by anastomosing network of up to 15-km-wide, 600-km-long and north-oriented high-strain zones, which originated during Neoproterozoic convergence. The studied Bouguer anomalies obtained from the International Gravimetric Bureau were high-pass filtered to emphasise short-wavelength gravimetric variations (shorter than 200 km). The Pan-African high-strain zones coincide with the positive gravimetric anomalies suggesting a link with deep seated high-density material. Considering the present-day thickness of the crust (35 km) and its seismic velocity record, the gravimetric anomalies can be visualised as narrow vertical tabular bodies located at the base of the Moho. Modelling further confirmed that such narrow vertical bodies could be stable over geologic time scale since these structures are relatively small (10 to 30 km wide). The vertical tabular bodies possibly reflect material transfer such as vertical motion of sub-crustal weak and possibly partially molten mantle along vertical deformation zones. It is proposed that these structures were initiated by folding of weak mantle-crust interface characterised by low-viscosity contrast between weak mantle and stronger granulitized lower crust during bulk pure shear-dominated horizontal shortening. It is proposed that the cuspate-lobate "mullion-type" geometry mimics rheological inversions of mafic and felsic rocks and shape of folds of variable scale observed in southern Madagascar. The formation of such mega-mullion structures is possibly an expression of "crème brulée" rheological model, where the deformation of the lithosphere is governed by stronger granulitic lower crust and weaker partially molten and/or hydrated mantle.
DS201709-1984
2017
Martelet, J-E.Feneyrol, J., Giuliani, G., Demaiffe, D., Ohenstetter, D., Fallick, A.E., Dubessy, J., Martelet, J-E., Rakotondrazafy, A.F.M., Omito, E., Ichangi, D., Nyamai, C., Wamunyu, W.Age and origin of the tsavorite and tanzanite mineralozing fluids in the Neoproterozoic Mozambique metamorphic belt.The Canadian Mineralogist, Vol. 55, pp. 763-786.Africa, Kenya, Tanzania, Madagascartanzanite

Abstract: The genetic model previously proposed for tsavorite- (and tanzanite-) bearing mineralization hosted in the Neoproterozoic Metamorphic Mozambique Belt (stretching from Kenya through Tanzania to Madagascar) is refined on the basis of new Sm-Nd age determinations and detailed Sr-O-S isotope and fluid-inclusion studies. The deposits are hosted within meta-sedimentary series composed of quartzites, graphitic gneisses, calc-silicate rocks intercalated with meta-evaporites, and marbles. Tsavorite occurs either in nodules (also called “boudins”) oriented parallel to the metamorphic foliation in all of the deposits in the metamorphic belt or in quartz veins and lenses located at the hinges of anticlinal folds (Lelatema fold belt and Ruangwa deposits, Tanzania). Gem tanzanite occurs in pockets and lenses in the Lelatema fold belt of northern Tanzania. The Sm-Nd isotopic data for tsavorites and tanzanites hosted in quartz veins and lenses from Merelani demonstrate that they formed at 600 Ma, during the retrograde metamorphic episode associated with the East African Orogeny. The tsavorites hosted in nodules do not provide reliable ages: their sedimentary protoliths had heterogeneous compositions and their Sm-Nd system was not completely rehomogenized, even at the local scale, by the fluid-absent metamorphic recrystallization. The initial 87Sr/86Sr isotopic ratios of calcite from marble and tanzanites from Merelani fit with the strontium isotopic composition of Neoproterozoic marine carbonates. Seawater sediment deposition in the Mozambique Ocean took place around 720 Ma. The quartz-zoisite O-isotopic thermometer indicates a temperature of formation for zoisite between 385 and 448 °C. The sulfur isotopic composition of pyrite (between –7.8 and –1.3‰ V-CDT) associated with tsavorite in the Lelatema fold belt deposits suggests the contribution of reduced marine sulfate. The sulfur in pyrite in the marbles was likely derived from bacterial sulfate reduction which produced H2S. Fluid inclusion data from tsavorite and tanzanite samples from the Merelani mine indicate the presence of a dominant H2S-S8±(CH4)±(N2)±(H2O)-bearing fluid. In the deposits in Kenya and Madagascar, the replacement of sulfate by tsavorite in the nodules and the boron isotopic composition of tourmaline associated with tsavorite are strong arguments in favor of the participation of evaporites in garnet formation.
DS201812-2851
2018
Marten, B.E.Moss, S., Marten, B.E., Felgate, M., Smith, C.B., Chimuka, L., Matchan, E.L., Phillips, D.Murowa deposit: Geology, structure and radiometric age determination of the Murowa kimberlites, Zimbabwe.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 379-402.Africa, Zimbabwedeposit - Murowa
DS2001-0152
2001
Martens, H.Butler, H., Martens, H.Northern latitudes mining reclamation workshop... abstract29th. Yellowknife Geoscience Forum, Nov. 21-23, abstract p.9.Northwest TerritoriesMine reclamation - mine tailings, Deposit - Ekati
DS1920-0160
1923
Martens, J.H.C.Martens, J.H.C.Study of Igneous Rocks of Ithaca, New York and VicinityGeological Society of America (GSA) Bulletin., Vol. 34, No. 1, P. 99.United States, Appalachia, New YorkGeology, Related Rocks
DS1920-0161
1923
Martens, J.H.C.Martens, J.H.C.A Study of the Basic Dikes of the Ithaca RegionMsc. Thesis, Cornell University, 101P.United States, Appalachia, New YorkPetrology
DS1920-0188
1924
Martens, J.H.C.Martens, J.H.C.Igneous Rocks of Ithaca, New York and VicinityGeological Society of America (GSA) Bulletin., Vol. 35, PP. 305-320.United States, Appalachia, New YorkGeology, Related Rocks
DS2003-0878
2003
Martens, P.Martens, P., Rotmans, J., De Groot, D.Biodiversity: luxury or necessityGlobal Environmental Change, Part A, Vol. 13, 2, pp. 75-81.GlobalBiodiversity - Not specific to diamonds
DS200412-1231
2003
Martens, P.Martens, P., Rotmans, J., De Groot, D.Biodiversity: luxury or necessity.Global Environmental Change, Part A, Vol. 13, 2, pp. 75-81.GlobalBiodiversity - Not specific to diamonds
DS201502-0077
2014
Martens, U.Martens, U., Restrepo, J.J., Ordonez-Carmona, O., Correa-Martinez, A.M.The Tahami and Anaconda terranes of the Colombian Andes: missing links between South American and Mexican Gondwana margins.Journal of Geology, Vol. 122, Sept. pp. 507-530.South America, MexicoTectonics
DS2000-0563
2000
Marti, J.Legros, F., Kelfoun, K., Marti, J.The influence of conduit geometry on the dynamics of caldera forming eruptions.Earth and Planetary Science Letters, Vol. 179, No. 1, June 15, pp. 53-62.Globalvolcanism - calderas, PhreatomagmatisM.
DS201806-1235
2018
Marti, J.Marti, J., Groppelli, G., Brum da Silveira, A.Volcanic stratigraphy: a review.Journal of Volcanology and Geothermal Research, Vol. 357, pp. 68-91.Mantlevolcanism

Abstract: Volcanic stratigraphy is a fundamental component of geological mapping in volcanic areas as it yields the basic criteria and essential data for identifying the spatial and temporal relationships between volcanic products and intra/inter-eruptive processes (earth-surface, tectonic and climatic), which in turn provides greater understanding of the geological evolution of a region. Establishing precise stratigraphic relationships in volcanic successions is not only essential for understanding the past behaviour of volcanoes and for predicting how they might behave in the future, but is also critical for establishing guidelines for exploring economic and energy resources associated with volcanic systems or for reconstructing the evolution of sedimentary basins in which volcanism has played a significant role. Like classical stratigraphy, volcanic stratigraphy should also be defined using a systematic methodology that can provide an organised and comprehensive description of the temporal and spatial evolution of volcanic terrain. This review explores different methods employed in studies of volcanic stratigraphy, examines four case studies that use differing stratigraphic approaches, and recommends methods for using systematic volcanic stratigraphy based on the application of the concepts of traditional stratigraphy but adapted to the needs of volcanological environment.
DS201212-0574
2012
Martignago, F.Princivalle, F., Martignago, F., Nestola, F., Dal Negro, A.Kinetics of cation ordering in synthetic Mg(Al,Fe3+2O4 spinels.European Journal of Mineralogy, Vol. 24, 4, pp. 633-643.TechnologySpinel
DS1989-0638
1989
Martignole, J.Higgins, M.D., Feininger, T., Martignole, J., Nantel, S.The Sept Iles layered mafic intrusion and the anorthosite complex of Riviere PentecoteGeological Association of Canada (GAC) Field Trip, May 17-21, NoQuebecXenoliths
DS1989-1279
1989
Martignole, J.Rivers, T., Martignole, J., Gower, C.F., Davidson, A.New tectonic divisions of the Grenville Province southeastCanadianshieldTectonics, Vol. 8, No. 1, February pp. 63-84OntarioOrogeny -Grenville, Tectonics
DS1992-1006
1992
Martignole, J.Martignole, J.Exhumation of high grade terranes - a reviewCanadian Journal of Earth Sciences, Vol. 29, pp. 737-745.Globalmetamorphism, Magmatic arcs
DS1994-0222
1994
Martignole, J.Brunet, S., Martignole, J.Nepheline bearing rocks of the reservoir Cabonga area, Grenville ProvinceQuebec: a possible carbonatitic origin.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p. posterQuebecCarbonatite, Cabonga
DS1995-0220
1995
Martignole, J.Brunet, S., Martignole, J.Gneiss et pegmatites a nepheline du reservoir Cabonga, parc de la VerendryeQuebec Department of Mines, MB 95-04, 35p.QuebecNepheline syenite
DS1996-0894
1996
Martignole, J.Martignole, J., Calvert, A.J.Crustal scale shortening and extension across the Grenville Province Of western Quebec.Tectonics, Vol. 15, No. 2, Apr. pp. 376-86.Quebec, LabradorGeophysics - seismics
DS1998-0947
1998
Martignole, J.Martignole, J., Friedman, R.Geochronological constraints on the last stages on terrane assembly in the central part of Grenville ProvPrecambrian Research, Vol. 92, No. 2, Oct.l, pp. 145-64OntarioGeochronology - tectonics, Terrane - Grenville Province
DS2000-0622
2000
Martignole, J.Martignole, J., Calvert, A.J., Friedman, R., ReynoldsCrustal evolution along a seismic section across the Grenville Province, western Quebec.Canadian Journal of Earth Sciences, Vol.37, No.2-3, Feb.Mar, pp.291-306.QuebecGeophysics - seismics, Tectonics
DS2002-1315
2002
MartikhaevRazvozzhaeva, E.A., Prokofev, Spiridonov, MartikhaevPrecious metals and carbonaceous substance in ores of the Sukhoi Log deposit, Eastern Siberia, Russia.Geology of Ore Deposits, Vol.44,2,pp. 103-110.RussiaGold, carbon, metallogeny, Deposit - Sukhoi Log
DS2001-0720
2001
MartinMajaule, T., Hanson, Key, Singletary, Martin, BowringThe Magondi belt in northeast Botswana: regional relations and new geochronological dat a from Sua PanJournal of African Earth Sciences, Vol. 32, No. 2, pp. 257-67.BotswanaOrogeny, Geochronology - mentions diamond area
DS1992-0122
1992
Martin, A.Bickel, M.J., Martin, A., Nisbet, E.G., Orpen, J.L., et al.The geology of the Belingwe greenstone belt, ZimbabweA.a. Balkema, approx. $ 70.00ZimbabweBook -Greenstone belt, Crustal evolution
DS1994-0159
1994
Martin, A.Bickle, M.J., Nisbet, G.G., Martin, A.Archean greenstone belts are not oceanic crustJournal of Geology, Vol. 102, No. 2, March pp. 121-138ZimbabweGreenstone belts, Crust -oceanic
DS1998-0649
1998
Martin, A.Hunter, M.A., Bickle, M.J., Nisbet, E.G., Martin, A.Continental extensional setting for the Archean Belingwe Greenstone Belt, ZimbabweGeology, Vol. 26, No. 10, Oct. pp. 883-6ZimbabweGreenstone belt - Belingwe, Tectonics
DS1910-0203
1911
Martin, A.H.Martin, A.H.Mining for Precious Stones in CaliforniaMining and Scientific Press, Vol. 63, MARCH 23RD. PP. 316-317.United States, California, West CoastBlank
DS1981-0285
1981
Martin, A.K.Martin, A.K., Hartnady, C.J.H., Goodlad, S.W.Pre-drift Fit of the Natal Valley and the Falkland PlateauCape Town: Tech. Report Mar. Geosci. Unit, Geological Survey South, No. 12, PP. 30-44.South Africa, South AmericaTectonics
DS1987-0437
1987
Martin, A.K.Martin, A.K.Plate reorganizations around Southern Africa, hot spot sand SOURCE[ TectonophysicsTectonophysics, Vol. 142, No. 2-4, November 1, pp. 309-316South AfricaBlank
DS201112-0646
2011
Martin, A.M.Martin, A.M., Hammouda, T.Role of iron and 6 GPa a potential mechanism for diamond formation during subduction.European Journal of Mineralogy, Vol. 23, 1, pp. 5-16.MantleDiamond genesis
DS201112-0647
2011
Martin, A.M.Martin, A.M., Hammouda, T.Role of iron and reducing conditions on the stability of dolomite + coesite between 4.25 and 6 GPa - a potential mechanism for diamond formation during subductionEuropean Journal of Mineralogy, Vol. 23, 1, pp. 5-16.MantleSubduction, diamond genesis
DS201212-0445
2012
Martin, A.M.Martin, A.M., Laporte, D., Koga, K.T., Kawamoto, T., Hammouda, T.Experimental study of the stability of a dolomite + coesite assemblage in contact with peridotite: implications for sediment-mantle interaction and diamond formation during subduction.Journal of Petrology, Vol. 53, 2, pp. 391-417.TechnologyUHP, diamond genesis
DS201212-0446
2012
Martin, A.M.Martin, A.M., Laporte, D., Koga, K.T., Kawamoto, T., Hammouda, T.Experimental stidy of the stability of a dolomite + coesite assembalge in contact with peridotite: implications for sediment-mantle interaction and diamond formation during subduction.Journal of Petrology, Vol. 53, 2, pp. 391-417.MantleSubduction
DS201312-0577
2013
Martin, A.M.Martin, A.M., Righter, K.Melting of clinopyroxene + magnesite in iron-bearing planetary mantles and implications for the Earth and Mars.Contributions to Mineralogy and Petrology, Vol. 166, 4, pp. 1067-1098.MantleCarbonatite, kamafugite
DS201510-1785
2015
Martin, A.P.Martin, A.P., Price, R.C., Cooper, A.F., McCammon, C.A.Petrogenesis of the rifted southern Victoria Land lithospheric mantle, Antarctica, inferred from petrography, geochemistry, thermobarometry and oxybarometry of peridotite and pyroxenite xenoliths from the Mount Morning eruptive centre.Journal of Petrology, Vol. 56, 1, pp. 193-226.AntarcticaMelting, subduction

Abstract: The lithospheric mantle beneath West Antarctica has been characterized using petrology, whole-rock and mineral major element geochemistry, whole-rock trace element chemistry and Mössbauer spectroscopy data obtained on a suite of peridotite (lherzolite and harzburgite) and pyroxenite xenoliths from the Mount Morning eruptive centre, Southern Victoria Land. The timing of pyroxenite formation in Victoria Land overlaps with subduction of the Palaeo-Pacific plate beneath the Gondwana margin and pyroxenite is likely to have formed when fluids derived from, or modified by, melting of the subducting, eclogitic, oceanic crustal plate percolated through peridotite of the lithospheric mantle. Subsequent melting of lithospheric pyroxenite veins similar to those represented in the Mount Morning xenolith suite has contributed to the enriched trace element (and isotope) signatures seen in Cenozoic volcanic rocks from Mount Morning, elsewhere in Victoria Land and Zealandia. In general, the harzburgite xenoliths reflect between 20 and 30% melt depletion. Their depleted element budgets are consistent with Archaean cratonization ages and they have mantle-normalized trace element patterns comparable with typical subcontinental lithospheric mantle. The spinel lherzolite mineral data suggest a similar amount of depletion to that recorded in the harzburgites (20-30%), whereas plagioclase lherzolite mineral data suggest <15% melt depletion. The lherzolite (spinel and plagioclase) xenolith whole-rocks have compositions indicating <20% melt depletion, consistent with Proterozoic to Phanerozoic cratonization ages, and have mantle-normalized trace element patterns comparable with typical depleted mid-ocean ridge mantle. All peridotite xenoliths have undergone a number of melt-rock reaction events. Melting took place mainly in the spinel peridotite stability field, but one plagioclase peridotite group containing high-sodium clinopyroxenes is best modelled by melting in the garnet field. Median oxygen fugacity estimates based on Mössbauer spectroscopy measurements of spinel and pyroxene for spinel-facies conditions in the rifted Antarctic lithosphere are -0·6 ?log fO2 at Mount Morning and –1·0 ± 0·1 (1?) ?log fO2 for all of Victoria Land, relative to the fayalite-magnetite-quartz buffer. These values are in good agreement with a calculated global median value of -0·9 ± 0·1 (1?) ?log fO2 for mantle spinel-facies rocks from continental rift systems.
DS200912-0474
2009
Martin, C.Martin, C.How to sell. A tale of shady jewellers honesty.... a salesperson is a human advertisement. Review in the National Post July 18, by M. Medley.Book Review, Publ. Farrar, Strauss and Giroux,United StatesBook review - just for interest!
DS1982-0403
1982
Martin, C.A.Martin, C.A.Diamonds: a Visit to Premier, the Prince of Diamond PipesChamber Mines Journal, Vol. 24, No. 4, PP. 35-43.South AfricaMining, Diamonds, Recovery, Geology
DS1984-0488
1984
Martin, C.A.Martin, C.A.Diamonds; Zimbabwe Engineer, 1984Zimbabwe Engineer., Vol. 22, No. 6, NOVEMBER PP. 514-515.South AfricaPremier, Mining Methods, Tailings, Diamond Morphology
DS1989-0949
1989
Martin, C.E.Martin, C.E.Rhenium- Osmium (Re-Os) isotopic investigations of the Stillwater Complex, MontanaEarth and Planetary Science Letters, Vol. 93, No. 3/4 July pp. 336-344. Database # 18092MontanaStillwater Complex, PlatinuM.
DS1991-1062
1991
Martin, C.E.Martin, C.E.Osmium isotopic characteristics of mantle derived rocksGeochimica et Cosmochimica Acta, Vol. 55, pp. 1421-1434GlobalMantle, Geochronology
DS1991-1063
1991
Martin, C.E.Martin, C.E., Esser, B.K., Turekian, K.K.Rhenium- Osmium (Re-Os) isotopic constraints on the formation of mantle and crustalAustralian Journal of Earth Sciences, Vol. 38, December pp. 569-576MantleCrustal reservoirs, Geochronology
DS201012-0120
2010
Martin, C.E.Cooper, A.F., Boztug, D., Palin, J.M., Martin, C.E., Numata, M.Petrology and petrogenesis of carbonatitic rocks in syenites from central Anatolia, Turkey.Contributions to Mineralogy and Petrology, in press available, 18p.Europe, TurkeyCarbonatite
DS201112-0206
2011
Martin, C.E.Cooper, A.F., Boztug, D., Palin, J.M., Martin, C.E., Numata, M.Petrology and petrogenesis of carbonatitic rocks in syenites from central Anatolia, Turkey.Contributions to Mineralogy and Petrology, Vol. 161, 5, pp. 811-828.Europe, TurkeyCarbonatite
DS201507-0322
2015
Martin, C.E.Liu, J., Scott, J.M., Martin, C.E., Pearson, D.G.The longevity of Archean mantle residues in the convecting upper mantle and their role in young continent formation.Earth and Planetary Science Letters, Vol. 424, pp. 109-118.MantleConvection
DS1987-0438
1987
Martin, D.Martin, D., Griffiths, R.W., Campbell, I.H.Compositional and thermal convection in magma chambersContributions to Mineralogy and Petrology, Vol. 96, No. 4, pp. 465-475GlobalXenoliths
DS1990-0992
1990
Martin, D.Martin, D.Crystal settling and in situ crystallization in aqueous solutions and magmachambersEarth and Planetary Science Letters, Vol. 96, pp. 336-348GlobalMagma chambers, Experimental petrology
DS1998-0948
1998
Martin, D. McB.Martin, D. McB., Clendenin, C.W., Krapez, B., McNaughtonTectonic and geochronological constraints on late Archean and Paleoproterozoic stratigraphic correlationJournal of the Geological Society of London, Vol. 155, pp. 311-22.South Africa, AustraliaCraton - Kaapvaal, Pilbara, Geochronology - SHRIMP
DS1986-0530
1986
Martin, D.C.Martin, D.C., Steenkamp, N.S.L., Lill, . J.W.Application of a statistical analysis technique for design of high rock slopes at Palabora mine, South AfricaInstitute of Mining and Metallurgy (IMM) Special Publishing Mining Latin America, pp. 241-255South AfricaCarbonatite, Palabora
DS1990-0993
1990
Martin, D.C.Martin, D.C., Zavodni, Z.M.Use of percussion drilling information for pit slope designAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, No. 90-128, 9pGlobalMining, Drilling -pit slope design
DS201612-2346
2016
Martin, D.McB.Wingate, M.T.D., Martin, D.McB.Updated digital map of mafic dyke swarms and large igneous provinces in Western Australia.Acta Geologica Sinica, Vol. 90, July abstract p. 14-15.AustraliaDykes
DS1900-0342
1905
Martin, D.S.Martin, D.S.Diamonds at Syracuse. #1Onondaga Academy of Science Proceedings, Oct. 24TH. MEETING.United States, Appalachia, New York, South AfricaDiamond Occurrences
DS200812-0716
2008
Martin, E.Martin, E., Martin, H., Sigmarsson, O.Could Iceland be a modern analogue for the Earth's early continental crust?Terra Nova, Vol. 20, no. 6, pp. 463-468.Europe, IcelandMantle
DS202010-1871
2020
Martin, E.Rebeiro, B.V., Cawood, P.A., Faleiros, F.M., Mulder, J.A., Martin, E., Finch, M.A., Raveggi, M., Teixeira, W., Cordani, U.G., Pavan, M.A long lived active margin revealed by zircon U-Pb-Hf data from the Rio Apa terrane (Brazil): new insights into the Paleoproterozoic evolution of the Amazonian craton.Precambrian Research, 57p. PdfSouth America, Brazilcraton

Abstract: We present the first regional in-situ zircon U-Pb-Hf isotopic data from metaigneous and metasedimentary rocks from the Paleo- to Mesoproterozoic Rio Apa Terrane (RAT), a crustal fragment outcropping in the central-western Brazil and north-eastern Paraguay. These new ages and Hf isotopic data delineate three magmatic events, which record the construction of the temporally and isotopically distinct Western and Eastern Terranes of the RAT. The Western Terrane comprises the 2100-1940 Ma Porto Murtinho Complex and the 1900-1840 Ma Amoguijá Belt, which both define a crustal reworking array in ?HfT-time space evolving from a precursor source with Hf TDM age of ca. 2700 Ma. The 1800-1720 Ma Caracol Belt constitutes the Eastern Terrane and yields suprachondritic ?HfT signatures up to +7.1, indicating significant juvenile input. The metasedimentary Amolar Group and Rio Naitaca Formation in the Western Terrane have maximum depositional ages of 1850-1800 Ma and subchondritic ?HfT signatures down to ?5.7, similar to the underlying basement of the Amoguijá Belt. In the Eastern Terrane, the Alto Tererê Formation has a maximum depositional age of 1750 Ma and mostly suprachondritic ?HfT signatures, similar to magmatic rocks of the underlying Caracol Belt. Together, the new igneous and detrital zircon age and Hf isotopic data record a temporal and spatial transition from 2100 to 1840 Ma crustal reworking in the west to more juvenile magmatism at 1800-1720 Ma in the east. This transition is interpreted to reflect convergent margin magmatism associated with periods of subduction zone advance and retreat in an accretionary orogenic setting. Comparison of the ?HfT-time signature of the RAT with the Amazonian Craton suggest penecontemporaneous development, with the Western and Eastern Terranes of the RAT being correlative with the Ventuari-Tapajós and Rio Negro-Juruena Province of the Amazonian Craton, respectively. Our new data also reveal that the ?HfT signatures of the RAT are distinct from the Maz terrane, which refutes the MARA Block hypothesis.
DS202102-0205
2020
Martin, E.L.Martin, E.L., Spencer, C.J., Collins, W.J., Thomas, R.J., Macey, P.H., Roberts, N.M.W.The core of Rodinia formed by the juxtaposition of opposed retreating and advancing accretionary orogens.Earth-Science Reviews, Vol. 211, doi.org/10.1016 /j.earscirev.2020 .103413 17p. Pdf Globalcratons

Abstract: Long-lived (800?Ma) Paleo- to Mesoproterozoic accretionary orogens on the margins of Laurentia, Baltica, Amazonia, and Kalahari collided to form the core of the supercontinent, Rodinia. Accretionary orogens in Laurentia and Baltica record predominately radiogenic zircon ?Hf(t) and whole-rock Pb isotopic compositions, short crustal residence times (ca. 0.5?Ga), and the development of arc-backarc complexes. The accretionary orogenic record of Laurentia and Baltica is consistent with a retreating accretionary orogen and analogous to the Phanerozoic western Pacific orogenic system. In contrast, the Mesoproterozoic orogens of Amazon and Kalahari cratons record unradiogenic zircon ?Hf(t) values, ca. 0.8?Ga crustal residence times, and more ancient whole-rock Pb isotopic signatures. The accretionary orogenic record of Amazonia and Kalahari indicates the preferential incorporation of cratonic material in continental arcs of advancing accretionary orogens comparable to the Phanerozoic eastern Pacific orogenic system. Based on similarities in the geodynamic evolution of the Phanerozoic circum-Pacific orogens peripheral to Gondwana/Pangea, we suggest that the Mesoproterozoic accretionary orogens formed as peripheral subduction zones along the margin of the supercontinent Nuna (ca. 1.8-1.6?Ga). The eventual collapse of this peripheral subduction zone onto itself and closure of the external ocean around Nuna to form Rodinia is equivalent to the projected future collapse of the circum-Pacific subduction system and juxtaposition of Australia-Asia with South America. The juxtaposition of advancing and retreating accretionary orogens at the core of the supercontinent Rodinia demonstrates that supercontinent assembly can occur by the closure of external oceans and indicates that future closure of the Pacific Ocean is plausible.
DS1989-0950
1989
Martin, F.Martin, F., Merigoux, H., Zecchini, P.Reflectance infrared spectroscopy in gemologyGems and Gemology, Vol. 25, No. 4, Winter pp. 226-231GlobalSpectroscopy, Mineral species -general
DS1984-0482
1984
Martin, G.Marot, A., Capdevila, R., Leveque, B., Gruau, G., Martin, G., Cha.Le Synclinorium du Sud de Guyane Francaise: une Ceinture Deroches Vertes D'age Proterozoic Inferieur.Annual DES SCIENCES DE la TERRE, 10TH. SESSION HELD BORDEAU, South America, GuyanaBlank
DS1950-0285
1956
Martin, H.Martin, H.Wenn Es Krieg Gibt, Gehen Wir in die WuesteStuttgart: Union Deutsche Verlag, 244P.South Africa, Namibia, Southwest AfricaBiography, Kimberley
DS1960-0574
1965
Martin, H.Martin, H.The Precambrian Geology of Southwest Africa and NamaqualandPrecambr. Res. Unit University Cape Town., 159P.Southwest Africa, Namibia, South AfricaGeology, Kimberley
DS1970-0680
1973
Martin, H.Ferguson, J., Martin, H., Nicolaysen, L.O., Danchin, R.Gross Brukkaros: a Kimberlite Carbonatite Volcano1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 107-110.Southwest Africa, NamibiaGeology
DS1975-0076
1975
Martin, H.Ferguson, J., Martin, H., Nicholson, L.O., Danchin, K.Gross Brukkaros, a Kimberlite Carbonatite VolcanoPhysics and Chemistry of the Earth., Vol. 9, PP. 219-234.Southwest Africa, NamibiaGibeon, Melilitite, Geology, Geochronology
DS1981-0286
1981
Martin, H.Martin, H.The Large BrukkarosJournal of SWA Scientific Society, Vol. 36-37, pp. 7-10Southwest Africa, NamibiaBlank
DS1984-0323
1984
Martin, H.Gruau, G., Martin, H., Leveque, B., Capdevila, R., Marot, A.Rubidium-strontium and Samarium-neodymium (sm-nd) Geochronology of Lower proterozoic Granite Greenstone Terrains in French Guiana, South America.B.r.g.m., IN PRESSSouth America, French GuianaBlank
DS1984-0489
1984
Martin, H.Martin, H.Uber die Herkunft der Diamanten an der Kueste von S.w.a. Namibia und Namaqualand.Mitteilungen Aus Dem Geologisch Palaeontologischen Institut, No. 56, PP. 31-44.South Africa, Southwest Africa, Namibia, NamaqualandBlank
DS1984-0490
1984
Martin, H.Martin, H.Uber die Herkunft der Diamanten an der Kuste von. S.W.A./Namibia undNamaqualand.(in German)Mitt. Geol. Palaont. Institute University of Hamburg., (in German), Vol. 56, pp. 31-44Southwest AfricaGenesis
DS1991-1064
1991
Martin, H.Martin, H., Sabate, P., Peucat, J.J., Cunha, J.C.An early Archean crustal segment (3.4 Ga) -the Sete Voltas Massif (Bahia, Brasil).(in French)Comptes Rendus de la'Academie des Sciences Serie II, Vol. 313, No. 5, August 29, pp. 531-538BrazilArchean, Craton
DS1993-0974
1993
Martin, H.Martin, H.The mechanisms of petrogenesis of the Archean continental crust -comparison with modern processesLithos, Vol. 30, No. 3-4, September pp. 373-388MantleCrust, Petrogenesis
DS1996-0159
1996
Martin, H.Bourgopis, J., Martin, H., Lagabrielle, Y., et al.Subduction erosion related to spreading ridge subduction: Titao peninsula(Chile triple junction)Geology, Vol. 24, No. 8, August pp. 723-726ChileSubduction, Tectonics
DS1997-0739
1997
Martin, H.Martin, H., Peucat, J.J., Cunha, J.C.Crustal evolution in the early Archean of South America: example of the Sete Voltas MassifPrecambrian Research, Vol. 82, No. 1-2, March 1, pp. 35-62Brazil, BahiaArchean, Geotectonics
DS2002-0997
2002
Martin, H.Martin, H., Moyen, J-F.Secular changes in tonalite trondhjemite granodiorite composition as markers of the progressive cooling earthGeology, Vol. 30,4,Apr.pp.319-22.MantleSlab melting, Archean
DS200712-0227
2007
Martin, H.De Souza, Z.S., Martin, H., Peucat, J-J., Jardim De Sa, E.F., De Frietas Macedo, M.H.Calc alkaline magmatism at the Archean Proterozoic transition: the Caico Complex basement ( NE Brazil).Journal of Petrology, Vol. 48, 11, pp. 2149-2185.South America, Brazil, SeridoMagmatism
DS200812-0681
2008
Martin, H.Lobach Zhuchenko, S.B., Rollinson, H., Chekulaev, V.P., Savatenkov, V.M., Kovalenko, A.V., Martin, H., Guseva, N.S., Arestova, N.A.Petrology of Late Archean, highly potassic, sanuktoid pluton from the Baltic Shield: insights into Late Archean mantle metasomatism.Journal of Petrology, Vol. 49, 3, pp. 393-420.Europe, Baltic shieldMetasomatism
DS200812-0716
2008
Martin, H.Martin, E., Martin, H., Sigmarsson, O.Could Iceland be a modern analogue for the Earth's early continental crust?Terra Nova, Vol. 20, no. 6, pp. 463-468.Europe, IcelandMantle
DS201012-0611
2010
Martin, H.Rapp, R.P., Norman, M.D., Laporte, D., Yaxley, G.M., Martin, H., Foley, S.F.Continent formation in the Archean and chemical evolution of the cratonic lithosphere: melt rock reaction experiments at 3-4 GPa and petrogenesisJournal of Petrology, Vol. 51, 6, pp. 1237-1266.MantleSanukitoids
DS1998-0949
1998
Martin, J.Martin, J., Edgley, G.J.Environmental management systems: a guide for planning, development andimplementationGovernment Institutes, $ 75.00GlobalBook - ad, Environment
DS200412-0105
2003
Martin, J.Barton, J.M., Barnett, W.P., Barton, E.S., Barnett, M., Doorgapershad, A., Twiggs, C., Klemd, B.R., Martin, J.The geology of the areas surrounding the Venetia kimberlite pipes, Limpopo belt, South Africa: a complex interplay of Nappe tectSouth African Journal of Geology, Vol. 106, 2-3, pp. 109-128.Africa, South AfricaDeposit - Venetia, tectonics
DS200412-0470
2003
Martin, J.Doorgapershad, A., Barnett, M., Twiggs, C., Martin, J., Millonig, L., Zenglein, R.Procedures used to produce a digitized geological mapping database of the area around the Venetia kimberlite pipes, Limpopo BeltSouth African Journal of Geology, Vol. 106, 2-3, pp. 103-108.Africa, South AfricaDeposit - Venetia, mapping
DS200412-1015
2003
Martin, J.Klemd, R., Martin, J., Schmidt, A., Barton, J.M.P-T path constraints from calc silicate metapelitic rocks east of the Venetia kimberlite pipes, Central Zone, Limpopo Belt, SoutSouth African Journal of Geology, Vol. 106, 2-3, pp. 129-148.Africa, South AfricaDeposit - Venetia, metamorphism, geochronology
DS1975-0781
1978
Martin, J.A.Kisvarsanyi, G., Martin, J.A.Tectonic and Metallogenic Significance of Major Structural Lineaments in the Mid-continent.Geological Society of America (GSA), Vol. 10, No. 1, P. 8. (abstract.).GlobalMid-continent
DS1975-1126
1979
Martin, J.E.Martin, J.E.Ashton Joint Venture- Second Quarter 1979 Progress Report. Attachment to Letter from Jem to Ajaj.In House Unpubl. Report., 3P.Australia, Western AustraliaGrades, Tonnages, Sampling, Stones, Carats
DS201412-0380
2014
Martin, L.Huang, J-X., Griffin, W.L., Greau, Y., Pearson, N.J., O'Reilly, S.Y., Cliff, J., Martin, L.Unmasking xenolithic eclogites: progressive metasomatism of a key Roberts Victor sample.Chemical Geology, Vol. 364, pp. 55-65.Africa, South AfricaDeposit - Roberts Victor
DS201709-1999
2017
Martin, L.Huang, J-X., Xiong, Q., Griffin, W.L., Martin, L., Toledo, V., O'Reilly, S.Y.Moissanite in volcanic systems: super reduced conditions in the mantle.Goldschmidt Conference, abstract 1p.Mantlemoissanite

Abstract: Moissanite (SiC) occurs in mantle and mantle-generated rocks from different tectonic settings. SiC is stable only at low oxygen fugacity (ƒO2) ?IW. Israeli SiC is assiociated with corundum, Fe globules, native V and other phases in Cretaceous pyroclastic rocks from Mt Carmel and associated alluvial deposits[1]. The SiC grains contain inclusions of Si metal, FeSi2, FeTiSi2, FeAlSi2 and CaSi2+xSi2-x, which were liquids before being trapped during SiC crystallization. SiC has been found included in corundum, associated with Fe-Ti silicides, connecting the formation of SiC, reduced melts in corundum and conrundum itself. All grains are of the 6H polytype. ?13C ranges from - 32.1 to -24.5‰ and ?30Si from -0.68 to +1.42‰. These SiC grains are one product of the interaction of basaltic magma and mantle methane in a volcanic plumbing system. SiC crystallized from metallic melts that became immiscible during the reduction of the magma. Its low ?13C may reflect Rayleigh fractionation under reduced conditions; the variation in Si isotopes may reflect fractionation between SiC and immiscible metallic melts. SiC samples from the Udachnaya and Mir kimberlite pipes contain inclusions of Si metal, FeSi2, FeSi, FeTiSi2, Si(N,O). The SiC has ?13C ranging from -28.5 to -24.8‰, and ?30Si from -1.72 to +1.42‰. SiC from harzburgites, chromitites and pyroxenites of the Tibetan Zedang ophiolites have inclusions of Si metal and unmixed Fe-Ni-Ti-Si alloy. Their ?13C ranges from -30.6 to -24.7‰ and ?30Si from -0.85 to +1.26‰. SiC samples from these different settings show very similar characteristics, implying that they may be formed in similar mantle conditions, where the flux of mantle methane gradually reduces magmas and interacts with them to produce different reduced phases at different stages.
DS201810-2372
2018
Martin, L.Rielli A., Tomkins, A.G., Nebel, O., Raveggi, M., Jeon, H., Martin, L., Laure, A., Janaina, N.Sulfur isotope and PGE systematics of metasomatised mantle wedge.Earth and Planetary Science Letters, Vol. 497, 1, pp. 181-192.Mantlemetasomatism

Abstract: At convergent margins fluids liberated from subducting slabs metasomatise the overlying mantle wedge, enriching it in volatiles, incompatible elements and possibly ore-forming metals. Despite the genetic link between this process, the genesis of arc magmas, and formation of porphyry Cu-Au deposits, there is currently little understanding of the behaviour of chalcophile and siderophile elements during subduction-related mantle metasomatism. In this study, we report sulfur isotopic compositions and PGE concentrations of sulfides in a suite of garnet peridotites from the Western Gneiss Region of Norway, sampling mantle wedge from ?100 to ?250 km depth. Sulfides hosted in metasomatised samples have deviated from typical mantle values, ranging between ?10.0 and +5.4‰, indicating derivation of sulfur from subducted crust. Sulfides in pervasively metasomatised samples have atypical PGE signatures, with strong enrichment in Os and Ru relative to Ir, whereas channelised fluid flow produced sulfides extremely enriched in Pd, up to 700 times the concentration found in non-metasomatised samples. These signatures are reconcilable with a high oxidation state of the metasomatising agents and demonstrate that subduction can recycle chalcophile and siderophile elements into and within the mantle, along with sulfur. We further show that because the solubility of Os and Ru in fluids is redox sensitive, and Pd is more soluble than the I-PGE, ratios such as Os/Ir, Ru/Ir plotted against Pd/Ir can be used to trace the metasomatic oxidation of mantle samples, mantle-derived magmas and porphyry Cu±Au deposits. This geochemical insight is used to show that Au-rich porphyry Cu deposits are derived from more oxidised mantle wedge than Au-poor porphyry deposits.
DS202102-0237
2021
Martin, L.Yakmchuck, C., Kirkland, C.L., Cavosie, A.J., Szilas, K., Hollis, J., Gardinerm N.J., Waterton, P., Steenfelt, A., Martin, L.Stirred not shaken; critical evaluation of a proposed Archean meteorite impact in West Greenland.Earth and Planetary Science Letters, Vol. 557, doi.org/10.1016/ j.epsl.2020.116730 9p. PdfEurope, Greenlandmeteorite

Abstract: Large meteorite impacts have a profound effect on the Earth's geosphere, atmosphere, hydrosphere and biosphere. It is widely accepted that the early Earth was subject to intense bombardment from 4.5 to 3.8 Ga, yet evidence for subsequent bolide impacts during the Archean Eon (4.0 to 2.5 Ga) is sparse. However, understanding the timing and magnitude of these early events is important, as they may have triggered significant change points to global geochemical cycles. The Maniitsoq region of southern West Greenland has been proposed to record a ?3.0 Ga meteorite impact, which, if confirmed, would be the oldest and only known impact structure to have survived from the Archean. Such an ancient structure would provide the first insight into the style, setting, and possible environmental effects of impact bombardment continuing into the late Archean. Here, using field mapping, geochronology, isotope geochemistry, and electron backscatter diffraction mapping of 5,587 zircon grains from the Maniitsoq region (rock and fluvial sediment samples), we test the hypothesis that the Maniitsoq structure represents Earth's earliest known impact structure. Our comprehensive survey shows that previously proposed impact-related geological features, ranging from microscopic structures at the mineral scale to macroscopic structures at the terrane scale, as well as the age and geochemistry of the rocks in the Maniitsoq region, can be explained through endogenic (non-impact) processes. Despite the higher impact flux, intact craters from the Archean Eon remain elusive on Earth.
DS201905-1033
2019
Martin, L.A.J.Giuliani, A., Martin, L.A.J., Soltys,A., Griffin, W.L.Mantle like oxygen isotopes in kimberlites determined by in situ SIMS analyses of zoned olivine.Geochimica et Cosmochimica Acta, in press available, 19p.Africa, South Africa, Canada, South America, Brazildeposit - Lac de Gras, Paranaiba

Abstract: Kimberlites are the deepest melts produced on Earth that are erupted at the surface and can therefore provide unique insights into the composition and evolution of the mantle. Radiogenic isotopes provide ambiguous evidence for the occurrence of recycled crustal material in kimberlite sources. Oxygen isotopes can fractionate significantly only in the shallow crust, and thus represent a powerful tracer of subducted material in the sources of kimberlite. To constrain the oxygen isotope composition of kimberlite melts, we have examined olivine grains in eleven Cretaceous to Eocene archetypal kimberlites from southern Africa, Lac de Gras (Canada) and Alto Paranaiba (Brazil), which exhibit radiogenic isotope evidence for recycled crustal material in their sources including highly radiogenic Pb isotopes and Nd-Hf isotope compositions deviating below the mantle array. Olivine grains are commonly zoned between a mantle-derived xenocrystic core and one or more magmatic overgrowths, i.e. occasional internal zones, ubiquitous rims and rare rinds (moving outward from the core). The oxygen isotope composition of different olivine zones was determined in situ within separated olivine grains by secondary ion mass spectrometry (SIMS) after point selection using back-scattered electron (BSE) images combined with major and minor element analyses. With the exception of a few cores, the ?18O values of different olivine zones do not deviate from typical mantle olivine values of 5.18?±?0.28‰ (Mattey et al., 1994). There are no correlations between oxygen isotopes and major/minor element compositions for internal zones and rims from individual localities or in the entire dataset. This indicates that the oxygen isotope composition of kimberlite melts is not affected by melt differentiation to the point of olivine rim crystallisation. However, olivine rinds from the Koala kimberlite (Canada) display an inverse correlation between ?18O and Mn-Ca concentrations, with ?18O values extending below the mantle range, which is probably due to carbonate fractionation, CO2 degassing and/or assimilation of serpentine-rich material after kimberlite emplacement in the upper crust. The mantle-like ?18O composition of olivine internal zones and rims suggests that assimilation of mantle material and liberation of a CO2-rich phase during ascent in the mantle do not significantly modify the original ?18O signature of kimberlite melts. Modelling of oxygen isotope fractionation shows that up to 15 wt% of CO2 can be lost by kimberlites en route to the upper crust. Our results combined with mass balance calculations indicate that only a limited amount (<5-10 wt%) of recycled crustal material could occur in the source of kimberlites from southern Africa, Lac de Gras and Alto Paranaiba, or that the recycled material had an oxygen isotope composition similar to the mantle.
DS202107-1094
2021
Martin, L.A.J.Consuma, G., Aulbach, S., Braga, R., Martin, L.A.J., Tropper, P., Gerdes, A., Fiorentini, M.L.Multi-stage sulfur and carbon mobility in fossil continental subduction zones: new insights from carbonate-bearing orogenic peridotites. *** Not specific to diamondsGeochimica et Cosmochimica Acta, Vol. 306, pp. 143-170. pdfEurope, Italysubduction

Abstract: The volatile transfer in subduction zones and the role of sulfate as a vector for the mobilization of oxidized components from down-going slabs remain hotly debated issues. Orogenic spinel and garnet peridotite lenses from the Ulten Zone (Eastern Alps, Italy), exhumed as part of felsic metamorphic terranes in continental collision zones, bear witness to mass transfer processes in these pivotal environments. In this study, we carried out a multi-method investigation of mantle sulfides coexisting with four generations of carbonates, indicating coupled sulfur and carbon mobility throughout the peridotites’ metamorphic evolution as part of the Variscan subduction architecture. Detailed petrography, bulk rock measurements, in situ chemical and geochemical analyses of sulfides as well as Sr isotope analyses of associated clinopyroxene and amphibole are combined with the aim to constrain the origin, nature and effect of multiple C-O-H-S-bearing fluids and melts the peridotites interacted with. The first, pre-peak, metasomatic pulse (Stage 1) is represented by an H2S-CO2-bearing melt from the subduction-modified hot mantle wedge, which formed a pyroxenite layer hosting matrix pentlandite with ?34S of +2.77‰. Matrix carbonates occasionally occur in the coarse-grained peridotite under eclogite-facies conditions (Stage 2), with heavier ?34S (up to +3.43‰), radiogenic Sr (87Sr/86Srclinopyroxene > 0.7052) and elevated Pb abundances. These are ascribed to interaction with isotopically heavy melts carrying recycled crustal component, permissive of, but not requiring, involvement of oxidized S species. Conversely, isotopically lighter matrix pentlandite (?34S = ?1.62 to +0.67‰), and radiogenic Sr in amphibole (87Sr/86Sr = 0.7056) and associated dolomite (published data) from fine-grained garnet-amphibole peridotites may point to involvement of H2S-CO2-bearing crustal fluids, which variably equilibrated with the mantle before interacting with the peridotites. The post-peak Stage 3 marks the entrapment of peridotites into a tectonic mélange. Here, kelyphitization of garnet is catalyzed by further ingress of a S-bearing fluid (?34S = ?0.38‰), while carbonate veining with occasional sulfides bear witness to channelized fluid flow. Sulfide and amphibole grains in retrogressed spinel peridotites reveal the highest contents of fluid-mobile elements (As, Sb) and 87Sr/86Sramphibole up to 0.7074, suggesting late interactions with isotopically heavy crustal fluids at high fluid-rock ratios. Textural observations indicate that, during Stage 4, serpentinization of peridotites at low ƒS2 played an active role not only in CO2 release by conversion of dolomite to calcite + brucite intergrowths, but also in local removal of 32S during the final exhumation stage. Late channelized sulfur remobilization is evidenced by the serpentine + magnetite (±millerite ± calcite) vein carrying > 300 ppm S. Overall, the relatively narrow range of sulfur isotope composition (?34S = ?1.62 to +3.76‰) is indicative of limited interaction with isotopically heavy crustal liquids, and points to a subordinate role of subduction-derived sulfate throughout the extended fluid(melt)/rock evolution of the Ulten Zone peridotites, first in the mantle wedge and then as part of a tectonic mélange.
DS201212-0447
2012
Martin, L.H.J.Martin, L.H.J., Schmidt, M.W., Mattsson, H.B., Ulmer, P., Hametner, K., Gunther, D.Element partitioning between immiscible carbonatite-kamafugite melts with application to the Italian ultrapotassic suite.Chemical Geology, Vol. 320-321 pp. 96-112.Europe, ItalyCarbonatite
DS201312-0579
2013
Martin, L.H.J.Martin, L.H.J., Schmidt, M.W., Mattsson, H.B., Guenther, D.Element partitioning between immiscible carbonatite and silicate melts for dry and H2O bearing systems at 1-3 Gpa.Journal of Petrology, Vol. 54, pp. 2301-2338.MantleCarbonatite
DS201112-0408
2011
Martin, M.Hammouda, T., Andrault, D., Koga, K., Katsura, T., Martin, M.Ordering in double carbonates and implications for processes at subduction.Contributions to Mineralogy and Petrology, Vol. 161, 3, pp. 439-450.MantleSubduction
DS201811-2617
2018
Martin, M.Walter, B.F., Parsapoor, A., Braunger, S., Marks, M.A.W., Wenzel, T., Martin, M., Markl, G.Pyrochlore as a monitor for magmatic and hydrothermal processes in carbonatites from the Kaiserstuhl volcanic complex ( SW Germany).Chemical Geology, Vol. 498, pp. 1-16.Europe, Germanycarbonatite

Abstract: Pyrochlore from the Kaiserstuhl volcanic complex (SW Germany) shows textural and compositional differences between various coarse-grained calcite-carbonatite bodies (Badberg, Degenmatt, Haselschacher Buck, Orberg) and extrusive carbonatites (Henkenberg, Kirchberg). Oscillatory-zoned F-rich pyrochlore with up to 69?wt% Nb2O5 is common in all coarse-grained calcite-carbonatite bodies and probably formed during magmatic conditions. However, only in some of the samples from the Badberg, partly resorbed U- and Ta-enriched pyrochlore cores with up to 22?wt% UO2 and 9?wt% Ta2O5 have been identified, which are interpreted as being inherited from underlying nosean syenites. Pyrochlore data from a drill core penetrating the Badberg indicate increasing contents of REE, U, and Ta with depth, while Nb, F and Na contents decrease. This may reflect the combined effects of fractional crystallization and assimilation (AFC) or indicates a multi-stage emplacement of the carbonatitic magma. Patchy-zoned ceriopyrochlore and REE- and Th-enriched pyrochlore with up to 19?wt% total REE2O3 and 6.5?wt% ThO2 is largely restricted to samples from the Orberg and probably formed during hydrothermal conditions. This can be related to the relatively evolved character of the Orberg carbonatites, based on their relatively high whole-rock Nb/Ta and Zr/Hf mass ratios. This study demonstrates that the textural and compositional variation of pyrochlore in carbonatites is a powerful tool to distinguish magmatic, hydrothermal and weathering processes in carbonatitic systems.
DS1994-1116
1994
Martin, M.D.Martin, M.D., Hyyppa, R.R.The case for periodic outsider operational reviewsAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, Meeting held Albuquerque Feb. 14-17th, No. 94-167, 14pGlobalMining, Philosophy
DS1987-0135
1987
Martin, M.M.Davies, G., Thomaz, M.F., Nazare, M.H., Martin, M.M., Shaw, D.Radiative decay time of luminescence from the vacancy in diamondJournal of Phys. C. Solid State Phys, Vol. 20, No.1, Jan. 10, pp. L13-L17GlobalCrystallography
DS1990-1498
1990
Martin, M.W.Van Schmus, W.R., Martin, M.W., Sprowl, D.R., Geissman, J.Age, neodymium and lead isotopic composition and magnetic polarity for subsurface samples of the 1100 Ma midcontinent riftGeological Society of America (GSA) Annual Meeting, Abstracts, Vol. 22, No. 7, p. A174GlobalGeochronology, Geophysics -magnetics
DS1998-0574
1998
Martin, M.W.Hanson, R.E., Martin, M.W., Bowring, S.A., Munyanyiwauranium-lead (U-Pb) zircon age for Umkondo dolerites, eastern Zimbabwe: 1.1 Ga large igneous province ....Geology, Vol. 26, No. 12, Dec. pp. 1143-6.Zimbabwe, South Africa, AntarcticaGeochronology, Rodinia, Gondwana, Magmatism
DS1999-0087
1999
Martin, M.W.Bowring, S.A., Martin, M.W.high Pressure precision uranium-lead (U-Pb) geochronology, the tempo of evolution and the recordfrom Gondwana.Journal of African Earth Sciences, Vol. 28, No. 1, pp. 187-201.Geochronology
DS2001-1203
2001
Martin, M.W.Vinyu, M.L., Hanson, R.E., Martin, M.W., Bowringuranium-lead (U-Pb) zircon ages from craton margin Archean orogenic belt in northern Zimbabwe.Journal of African Earth Sciences, Vol. 32, No. 1, Jan. pp. 103-114.ZimbabweCraton, Geochronology
DS2003-0551
2003
Martin, M.W.Hargrove, U.S., Hanson, R.E., Martin, M.W., Blenkinsop, T.G., Bowring, S.A.Tectonic evolution of the Zambesi orogenic belt: geochronological, structural andPrecambrian Research, Vol. 123, 2-4, pp. 159-186.ZimbabweBlank
DS2003-1287
2003
Martin, M.W.Singletary, S.J., Hanson, R.E., Martin, M.W., Crowley, J.L., Bowring, S.A., KeyGeochronology of basement rocks in the Kalahari desert, Botswana, and implicationsPrecambrian Research, Vol. 121,1-2, Feb. 28, pp. 47-71.BotswanaGeochronology, Crustal provinces, belts - not specific to diamonds
DS200412-0790
2003
Martin, M.W.Hargrove, U.S., Hanson, R.E., Martin, M.W., Blenkinsop, T.G., Bowring, S.A., Walker, N., Munyanyiwa, H.Tectonic evolution of the Zambesi orogenic belt: geochronological, structural and petrological constraints from northern ZimbabwPrecambrian Research, Vol. 123, 2-4, pp. 159-186.Africa, ZimbabweTectonics
DS200412-1232
2004
Martin, M.W.Martin, M.W., Tannant, D.D.A technique for identifying structural domain boundaries at the Ekati diamond mine.Engineering Geology, Vol. 74, 3-4, pp. 247-264. Ingenta 1042990759Canada, Northwest TerritoriesMining - Ekati
DS200712-0690
2004
Martin, M.W.Martin, M.W., Tannant, D.D.A technique for identifying structural domain boundaries at the Ekati diamond mine.Engineering Geology, Vol. 74, 3-4, August pp. 247-264.Canada, Northwest TerritoriesDeposit - Ekati
DS1993-0975
1993
Martin, P.S.Martin, P.S.Diamond exploration opportunitiesPresentation notes Northeast Investment in Mining Conference, held New York, 8p.CanadaEconomics, Valuation
DS201112-0648
2011
Martin, R.Martin, R.Punctuated anorogenic magmatism.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, AbstractMantleMagmatism
DS1984-0534
1984
Martin, R.F.Morogan, V., Martin, R.F.Partial Melting of Fenitic Assemblages in the Oldoinyo Lengai Carbonatitic Volcano Tanzania.Geological Association of Canada (GAC), Vol. 9, P. 90. (abstract.).Tanzania, East AfricaBlank
DS1985-0080
1985
Martin, R.F.Bowden, P., Martin, R.F.Niger-nigeria Alkaline Ring Complexes: West Africa Representatives of African Phanerozoic Anorogenic Magmatism.Conference Report On A Meeting of Volcanics Studies Group He, 1P. ABSTRACT.Central Africa, NigerPetrogenesis, Geochemistry
DS1985-0467
1985
Martin, R.F.Morogan, V., Martin, R.F.Mineralogy and partial melting of fenitized crustal xenoliths in the Oldoinyo Lengai carbonatitic volcano, TanzaniaAmerican Mineralogist, Vol. 70, pp. 1114-1126TanzaniaCarbonatite
DS1995-1588
1995
Martin, R.F.Roelofsen, J.N., Martin, R.F., et al.Sequential alteration of mafic minerals in fenites from the Amba Bongar carbonatitic - alkaline complex GujaratGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Annual Meeting Abstracts, Vol. 20, p. A90 AbstractIndiaCarbonatite
DS1997-0851
1997
Martin, R.F.Nixon, G.T., Johnston, A.D., Martin, R.F.Nature and origin of primitive magmas at subduction zonesCanadian Mineralogist, Vol. 35, No. 2, AprilPhilippines, Mexico, British Columbia, NewfoundlandBook - table of contents, Magmas, subduction zones
DS2002-0998
2002
Martin, R.F.Martin, R.F., Barkov, A.Y.Negative Nb and Ta anomalies in subduction related magmas: insights from the discovery of edgarite.18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.219.MantleAlkaline magmas
DS200612-0084
2006
Martin, R.F.Barkov, A.Y., Fleet, M.E., Martin, R.F., Menshikov, Y.P.Sr Na REE titanates of the crichtonite group from a fenitized megaxenolith, Khibin a alkaline complex, Kola Peninsula, Russia: first occurrence and implications.European Journal of Mineralogy, Vol. 18, 4, August pp. 493-502.Russia, Kola PeninsulaCarbonatite
DS201112-0577
2011
Martin, R.F.Lehbib, S., Arribas, A., Melgarejo, J.C., Martin, R.F.Rare element minerals of the alkaline suites of the western Sahara.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterAfricaAlkalic
DS201112-0578
2011
Martin, R.F.Lehbib, S., Arribas, A., Melgarejo, J.C., Martin, R.F.Rare element minerals of the alkaline suites of the western Sahara.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.96-98.Africa, MauritaniaCarbonatite
DS201112-0579
2011
Martin, R.F.Lehbib, S., Arribas, A., Melgarejo, J.C., Martin, R.F.Rare element minerals of the alkaline suites of the western Sahara.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.96-98.Africa, MauritaniaCarbonatite
DS201212-0448
2012
Martin, R.F.Martin, R.F., Sokolov, M., Magaji, S.S.Punctuated anorogenic magmatism.Lithos, Vol. 152, pp. 132-140.Canada, Greenland, Russia, AfricaMagmatism
DS201412-0553
2014
Martin, R.F.Martin, R.F., Randrianandraisana, A., Boulvais, P.Ampandrandava and similar phlogopite deposits in southern Madagascar: derivation from a silicocarbonatitic melt of crustal origin.Journal of African Earth Sciences, Vol. 94, pp. 111-118.Africa, MadagascarCarbonatite
DS201702-0226
2016
Martin, R.F.Martin, R.F., Alarie, E., Minarik, W.G., Waczek, Z., McCammon, C.A.Titanium rich magneso-hastingite macrocrysts in a camptonite dike, Lafarge quarry, Montreal Island, Quebec: early crystallization in a pseudo-unary system.The Canadian Mineralogist, Vol. 54, pp. 65-78.Canada, QuebecCamptonite

Abstract: A prominent dike of camptonite cuts the Middle Ordovician Tétreauville Formation of the Trenton Group in the Montréal-Est quarry operated by Lafarge Canada Inc. The “Lafarge” dike is strikingly porphyritic, with largely anhedral macrocrysts of unzoned calcic amphibole up to 13 cm across. The macrocrysts are rimmed with ferri-kaersutite resembling the amphibole in the fine-grained matrix of the camptonite. The magnesio-hastingstite macrocrysts have virtually the same composition as the matrix; they thus grew without much of a boundary layer. The magma crystallized in a disequilibrium way as a pseudo-unary system. The macrocrysts are unusually enriched in Fe3+ (approximately 44% of the total iron), yet locally enclose globules of immiscible sulfide melt. The magma became oxygenated owing to preferential loss of hydrogen upon the dissociation of aqueous gas bubbles. The amygdaloidal macrocrysts have a relatively high ?D value because of this loss of H2; the values of ?18O are typical of an upper mantle source. Camptonite dikes are very common on Mont Royal. Like the Lafarge dike, they likely arose by the disequilibrium crystallization of batches of the parental melt of asthenospheric origin.
DS201911-2560
2019
Martin, R.F.Schumann, D., Martin, R.F., Fuchs, S., de Fourestier, J.Silicocarbonatitic melt inclusions in fluorapatite from the Yeates prospect, Otter Lake, Quebec: evidence of marble anatexis in the central metasedimentary belt of the Grenville Province.The Canadian Mineralogist, Vol. 57, pp. 583-604.Canada, Quebeccarbonatite

Abstract: We have investigated a locality very well known to mineral collectors, the Yates U-Th prospect near Otter Lake, Québec. There, dikes of orange to pink calcite enclose euhedral prisms of fluorapatite, locally aligned. Early investigators pointed out the importance of micro-inclusions in the prisms. We describe and image the micro-inclusions in two polished sections of fluorapatite prisms, one of them with a millimetric globule of orange calcite similar to that in the matrix. We interpret the globule to have been an inclusion of melt trapped during growth. Micro-globules disseminated in the fluorapatite are interpreted to have crystallized in situ from aliquots of the boundary-layer melt enriched in constituents rejected by the fluorapatite; the micro-globules contain a complex jigsawed assemblage of carbonate, silicate, and sulfate minerals. Early minerals to crystallize are commonly partly dissolved and partly replaced by lower-temperature phases. Such jigsawed assemblages seem to be absent in the carbonate matrix sampled away from the fluorapatite prisms. The pressure and temperature attained at the Rigolet stage of the Grenville collisional orogeny were conducive to the anatexis of marble in the presence of H2O. The carbonate melt is considered to have become silicocarbonatitic by assimilation of the enclosing gneisses, which were also close to their melting point. Degassing was important, and the melt froze quickly. The evidence points to a magmatic origin for the carbonate dikes and the associated clinopyroxenite, rather than a skarn-related association.
DS1990-0510
1990
Martin, R.M.Galli, G., Martin, R.M., Car, R., Parrinello, M.Melting of diamond at high pressureScience, Vol. 250, December 14, pp. 1547-1549GlobalDiamond synthesis, Thermal conductivity
DS201910-2269
2018
Martin, S.A.Kavanagh, J.L., Burns, A.J., Hilmi Hazim, S., Wood, E.P., Martin, S.A., Hignett, S., Dennis, D.J.C.Challenging dyke ascent models using novel laboratory experiments: implications for reinterpreting evidence of magma accent and volcanism.Journal of Volcanology and Geothermal Research, Vol. 354, pp. 87-101.Mantlemagmatism

Abstract: Volcanic eruptions are fed by plumbing systems that transport magma from its source to the surface, mostly fed by dykes. Here we present laboratory experiments that model dyke ascent to eruption using a tank filled with a crust analogue (gelatine, which is transparent and elastic) that is injected from below by a magma analogue (dyed water). This novel experimental setup allows, for the first time, the simultaneous measurement of fluid flow, sub-surface and surface deformation during dyke ascent. During injection, a penny-shaped fluid-filled crack is formed, intrudes, and traverses the gelatine slab vertically to then erupt at the surface. Polarised light shows the internal stress evolution as the dyke ascends, and an overhead laser scanner measures the surface elevation change in the lead-up to dyke eruption. Fluorescent passive-tracer particles that are illuminated by a laser sheet are monitored, and the intruding fluid's flow dynamics and gelatine's sub-surface strain evolution is measured using particle image velocimetry and digital image correlation, respectively. We identify 4 previously undescribed stages of dyke ascent. Stage 1, early dyke growth: the initial dyke grows from the source, and two fluid jets circulate as the penny-shaped crack is formed. Stage 2, pseudo-steady dyke growth: characterised by the development of a rapidly uprising, central, single pseudo-steady fluid jet, as the dyke grows equally in length and width, and the fluid down-wells at the dyke margin. Sub-surface host strain is localised at the head region and the tail of the dyke is largely static. Stage 3, pre-eruption unsteady dyke growth: an instability in the fluid flow appears as the central fluid jet meanders, the dyke tip accelerates towards the surface and the tail thins. Surface deformation is only detected in the immediate lead-up to eruption and is characterised by an overall topographic increase, with axis-symmetric topographic highs developed above the dyke tip. Stage 4 is the onset of eruption, when fluid flow is projected outwards and focused towards the erupting fissure as the dyke closes. A simultaneous and abrupt decrease in sub-surface strain occurs as the fluid pressure is released. Our results provide a comprehensive physical framework upon which to interpret evidence of dyke ascent in nature, and suggest dyke ascent models need to be re-evaluated to account for coupled intrusive and extrusive processes and improve the recognition of monitoring signals that lead to volcanic eruptions in nature.
DS1995-0467
1995
Martin, S.V.Dyar, M.D., Martin, S.V., et al.iron III and D/H in mantle derived augite megacrysts from Dish Hill, implications for alteration during transportGeological Society of America (GSA) Abstracts, Vol. 27, No. 6, abstract p. A 48.CaliforniaSpectroscopy, Hydrogen, Deposit -Dish Hill
DS1990-1463
1990
Martin, T.Thorp, M.B., Thomas, M.F., Martin, T., Whalley, W.B.Late Pleistocene sedimentation and landform development in western Kalimantan (Indonesian Borneo)Geologie en Mijnbouw, Vol. 69, No. 2, pp. 133-150GlobalSedimentology
DS2002-1415
2002
Martin, U.Schaltz, M., Resichmann, T., Tait, J., Bachtadse, V., Bahlburg, H., Martin, U.The Early Paleozoic break up of northern Gondwana, new paleomagnetic andInternational Journal of Earth Sciences, Vol. 91, No. 5, Oct. pp. 838-49.GermanyTectonics, Gondwana
DS200612-0871
2006
Martin, U.Martin, U., Nemeth, K., Lorenz, V., White, J.D.L.Introduction: maar-diatreme volcanism.Journal of Volcanology and Geothermal Research, In press, availableGlobalDiatreme
DS1990-0256
1990
Martin, W.E.Burness, H.S., Martin, W.E.The effects of global warming on the mining industry:issues, tradeoff sand optionsColorado School of Mines, Department of Mineral Economics, Working Paper, No. 90-3, 46pGlobalMining industry, Economics-global warming
DS1982-0402
1982
Martin f., C.Martin f., C.Metalogenesis En America Del SurI.u.g.s. Publn. Metalogenesis En Latinoamerica., No. 5, PP. 223-248.South America, BrazilLineaments, Tectonics, Structure
DS201212-0587
2012
Martin-Brandis, G.L.Roberts, G.G., White, N.J., Martin-Brandis, G.L., Crosby, A.G.An uplift history of the Colorado Plateau and its surroundings from the inverse modeling of longitudinal river profiles.Tectonics, Vol. 31, TC4022 26p.United States, CanadaGeomorphology
DS1996-0895
1996
Martin-Chivelet, J.Martin-Chivelet, J.Late Cretaceous subsidence history of the Betic continental Margin Jumilla- Vecla area.Tectonophysics, Vol. 265, No. 3/4, Nov. 30, pp. 191-212.GlobalJumilla, Lamproites
DS1985-0076
1985
Martineau, G.Bouchard, M.A., Martineau, G.Southeastward Ice Flow in Central Quebec and its Paleogeographic Significance.Canadian Journal of Earth Sciences., Vol. 22, No. 10, OCTOBER PP. 1536-1541Canada, QuebecGeomorphology
DS1982-0404
1982
Martineau, M.P.Martineau, M.P.Record Notes on Institute of Mining and Metallurgy (imm) Gemstone Conference Held December 1981 In London.Confidential Report In-house., DECEMBER 14TH. 5P.Australia, Western AustraliaGeology
DS1996-0896
1996
Martineau, M.P.Martineau, M.P., Davies, C.Merelani tanzanite - a unique occurrence.. Lelatema Mountains...stratigraphy, alteration zone, gradeMineral Industry International., No. April, pp.TanzaniaGemstone mining, marketing, Tanzanite
DS200712-0216
2006
Martineau, P.David, C., Collins, A.T., Martineau, P.Defects in single crystal CVD synthetic diamond studied by optical spectroscopy with the application of uniaxial stress.Gems & Gemology, 4th International Symposium abstracts, Fall 2006, p.121-2, abstract onlyTechnologyCVD diamond
DS201808-1767
2018
Martineau, P.Martineau, P., McGuiness, C.De Beers consumer confidence technical research and diamond verification instruments ( synthetic diamonds and their detection). SAIMM Diamonds - source to use 2018 Conference 'thriving in changing times'. June 11-13., 28 ppts.Globalspectrometry
DS200412-1233
2004
Martineau, P.M.Martineau, P.M., Lawson, S.C., Taylor, A.I., Quinn, S.J., Evans, D.J.F., Crowder, M.J.Identification of synthetic diamond grown using chemical vapor deposition (CVD).Gems & Gemology, Vol. 40, 1, Spring, pp. 2-25.TechnologyDiamond synthesis - review
DS200612-0604
2006
Martineau, P.M.Hounsome, L.S., Jones, R., Martineau, P.M., Fisher, D., Shaw, M.J., Briddon, P.R., Oberg, S.Origin of brown coloration in diamond.Physical Review Letters, Vol. 73, 12, pp. 125203 ( 8 pages)TechnologyDiamond - colour
DS200912-0466
2009
Martineau, P.M.Maki, J.M., Tuomisto, F., Kelly, C., Fisher, D., Martineau, P.M.Properties of optically active vacancy clusters in type IIa diamond.Journal of Physics Condensed Matter, in press ( August)TechnologyDiamond - morphology IIa
DS201012-0355
2010
Martineau, P.M.Khan, R.U.A., Martineau, P.M., Cann, B.L., Newton, M.E., Dhillon, H.K., Twitchen, D.J.Color alterations in CVD synthetic diamond with heat and UV exposure: implications for color grading and identification.Gems & Gemology, Vol. 46, 1, Spring pp. 18-27.TechnologyCVD synthetics
DS201807-1513
2018
Martineau, P.M.Martineau, P.M., McGuinness, C.D.De Beers consumer confidence technical research and diamond verification instruments. Absorption spectrometry, crystal morphology, melee PresentationSAIMM Diamonds - source to use 2018 Conference 'thriving in changing times'. June 11-13. Presentation, pp. 35-44.Technologyspectrometry
DS202012-2223
2020
Martineau, P.M.Jones, D.C., Kumar, S., Lanigan, P.M.P., McGuiness, C.D., Dale, M.W., Twichen, D.J., Fisher, D., Martineau, P.M., Neil, M.A., Dunsby, C., French, P.M.W.Multidemensional luminescence microscope for imaging defect colour centres in diamond.Methods and Applications in Flouresence, Vol. 8, 1, 01404 htpp:dx.doi.org/10.1088/2050-6120/ab4eacGloballuminescence

Abstract: We report a multidimensional luminescence microscope providing hyperspectral imaging and time-resolved (luminescence lifetime) imaging for the study of luminescent diamond defects. The instrument includes crossed-polariser white light transmission microscopy to reveal any birefringence that would indicate strain in the diamond lattice. We demonstrate the application of this new instrument to detect defects in natural and synthetic diamonds including N3, nitrogen and silicon vacancies. Hyperspectral imaging provides contrast that is not apparent in conventional intensity images and the luminescence lifetime provides further contrast.
DS200412-1781
2004
Martinec, J.Seidel, K., Martinec, J.Remote sensing in snow hydrology.Springer, 200p. approx. $ 120. ISBN 3-540-40880-0GlobalGeomorphology, glaciations, climate
DS200512-0689
2005
Martinec, Z.Martinec, Z., Wolf, D.Inverting the Fennoscandian relaxation time spectrum in terms of an axisymmetric viscosity distribution with a lithospheric root.Journal of Geodynamics, Vol. 39,2, March pp. 143-163.Europe, Fennoscandia, Norway, FinlandGlacial isostatic, geomorphology, mantle viscosity
DS200612-1477
2006
Martinec, Z.Velimsky, J., Martinec, Z., Everett, M.E.Electrical conductivity in the Earth's mantle inferred from CHAMP satellite measurements 1. Dat a processing and 1-D inversion.Geophysical Journal International, Vol. 166, 2, pp. 529-542.MantleGeophysics
DS200812-0565
2008
Martinec, Z.Kiemann, V., Martinec, Z., Ivins, E.R.Glacial isostasy and plate motion.Journal of Geodynamics, Vol. 46, 3-5, October pp. 95-103.MantleTectonics
DS1996-0948
1996
Martinelli, L.A.Mertes, L.A.K., Dunne, T., Martinelli, L.A.Channel floodplain geomorphology along the Solinoes Amazon River, BrasilGeological Society of America (GSA) Bulletin., Vol. 108, No. 9, Sept. pp. 1089-1107.BrazilGeomorphology, Alluvials - not specific to diamonds
DS1997-0638
1997
Martinez, A.Kruger, J.M., Martinez, A., Berendsen, P.Use of high resolution ground penetration radar in kimberlite delineationMining Engineering, Vol. 49, No. 11, Nov. pp. 73-79.GlobalGeophysics - Radar GPR., Deposit - Randolph 2
DS1991-1065
1991
Martinez, E.Martinez, E., Spiller, D.E.Gravity magnetic seperationEngineering and Mining Journal, Vol. 192, No. 6, June pp. 16 EE, 16 GG. (2p.)United StatesMineral processing -general, Gravity magnetics
DS1992-1007
1992
Martinez, E.Martinez, E.Recovery of non-magnetic minerals with a gravity magnetic seperatorAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, Annual Meeting held Phoenix Arizona Feb. 24-27th. 1992, Preprint No. 92-65, 6pGlobalMineral processing, Rutile, zircon, ilmenite
DS1990-1362
1990
Martinez, F.Sidder, G.B., Martinez, F.Geology, geochemistry and mineral resources of the upper Caura River at Bolivar State, VenezuelaUnited States Geological Survey (USGS) Open File, No. 90-0231, 29p. $ 5.00VenezuelaGeochemistry, General, Mineral resources
DS1995-1874
1995
Martinez, F.Taylor, B., Goodliffe, A., Martinez, F., Hey, R.Continental rifting and initial sea floor spreading in the Woodlark BasinNature, Vol. 374, No. 6522, April 6, p. 534-536.GlobalTectonics, Rifting
DS1995-1875
1995
Martinez, F.Taylor, B., Goodliffe, A., Martinez, F., Hey, R.Continental rifting and initial sea floor spreading in the Woodlark BasinNature, Vol. 374, April 6, pp. 534-537Papua New Guinea, Solomon IslandsTectonics, Rifting
DS2002-0999
2002
Martinez, F.Martinez, F., Taylor, B.Mantle wedge control on back arc crustal accretionNature, No. 6879, March 28, pp. 417-19.MantleSubduction
DS201012-0218
2010
Martinez, G.Gaucher, C., Frei, R., Chemale, F.Jr., Frei, D., Bossi, J., Martinez, G., Chiglino, L., Cernuschi, F.Mesoproterozoic evolution of the Rio de la Plat a Craton in Uruguay: at the heart of Rodinia?International Journal of Earth Sciences, In press available, 16p.South America, UruguayTectonics - not specific to diamonds
DS201112-0347
2011
Martinez, G.Gaucher, C., Frei, R., Chemale, F., Frei, D., Bossi, J., Martinez, G., Chiglino, L., Cernuschi, F.Mesoproterozoic evolution of the Rio de la Plat a craton in Uruguay: at the heart of Rodinia?International Journal of Earth Sciences, Vol. 100, 2, pp. 273-288.South America, UruguayCraton, Rodinia, Gondwana
DS1981-0184
1981
Martinez, G.M.Gomes, J.M., Martinez, G.M.Recovery of Gold and Other Heavy Minerals from Alluvial Deposits: Equipment and Practices.Reno Research Center, United States Bureau of Mines, 22P.United States, California, Oregon, Nevada, West Coast, Rocky MountainsDiamonds, Techniques, Sampling, Mineral Processing
DS1995-2028
1995
Martinez, I.Wang, Y., Martinez, I., Guyot, F., Liebermann, R.C.The breakdown of olivine to perovskite and magnesiowustiteEos, Vol. 76, No. 46, Nov. 7. p.F618. Abstract.MantleSubduction, Perovskite
DS200412-0942
2004
Martinez, I.Kadik, A., Pineau, F., Litvin, Y., Jendrzejewski, N., Martinez, I., Javoy, M.Formation of carbon and hydrogen species in magmas at low oxygen fugacity.Journal of Petrology, Vol. 45, 7, pp. 1297-1310.TechnologyMagmatism - not specific to diamonds
DS1991-1066
1991
Martinez, J.D.Martinez, J.D.Salt domesAmerican Scientist, Vol. 79, September-October pp. 420-430United StatesSalt domes
DS201312-0228
2013
Martinez, J-C.Dristas, J.A., Martinez, J-C., Massone, H-J., Pimentel, M.M.Mineralogical and geochemical characterization of a rare ultramafic lamprophyre in the Tandilia belt basement, Rio de la Plata, Argentina.Journal of South American Earth Sciences, Vol. 43, pp. 46-61.South America, ArgentinaLamprophyre
DS1993-0976
1993
Martinez, P.A.Martinez, P.A., Harbaugh, J.W.Simulating near shore environments... sediment transportPergamon Press, 280p. approx. $ 110.00GlobalBook -ad, Transport methodology
DS1990-0191
1990
Martinez Frias, J.Benito Garcia, R., Martinez Frias, J.BITCLA: GW-BASIC program to plot classification diagramsComputers and Geosciences, Vol. 16, No. 2, pp. 265-272GlobalProgram -BITCLA., Classification plots
DS1990-0192
1990
Martinez Friaz, J.Benito Garcia, R., Martinez Friaz, J.BITERCLA: GW-BASIC program to plot classification diagramsComputers and Geosciences, Vol. 16, No. 2, pp. 265-267GlobalComputer, Program - BITERCLA.
DS1989-1251
1989
Martinez-Torres, L.M.Ramon-Lluch, R., Martinez-Torres, L.M., Eguiluz, L.RAFOLD: a BASIC program for the geometric classification of foldsComputers and Geosciences, Vol. 15, No. 6, pp. 989-996GlobalComputer, Program -RAFOLD.
DS201312-0266
2013
Martin-Hernandez, F.Ferre, E.C., Friedman, S.A., Martin-Hernandez, F., Feinberg, J.M., Conder, J.A., Ionov, D.A.The magnetism of mantle xenoliths and potential implications for sub-Moho magnetic sources.Geophysical Research Letters, Vol. 40, 1, pp. 105-110.MantleMagnetism
DS201412-0255
2014
Martin-Hernandez, F.Friedman, S.A., Feinberg, J.M., Ferre, E.C., Demory, F., Martin-Hernandez, F., Condor, J.A., Rochette, P.Craton vs rift uppermost mantle contributions to magnetic anomalies in the United States interior.Tectonophysics, Tecto9071R.docxUnited States, Montana, Colorado PlateauGeophysics - magnetics
DS1989-0951
1989
Martini, I.P.Martini, I.P.The Hudson Bay Lowland: major geologic features and assetsGeologie en Mijnbouw, Vol. 68, pp. 25-34OntarioGeomorphology, Hudson Bay Lowlands, Paleozoic basins
DS1992-1008
1992
Martini, I.P.Martini, I.P., Chesworth, W.Weathering, soils and paleosolsElsevier, 632p. approx. $ 135.00 United StatesGlobalBook -ad, Weathering, soils, paleosols, laterites
DS1982-0405
1982
Martini, J.E.J.Martini, J.E.J., Hammerbeck, E.C.I., et al.Mineral Map of the Republics of South Africa, Transkei, Bophuthatswana, Venda and Ciskei and the Kingdoms of Lesotho And Swaziland.Department MINERAL AND ENERGY AFFAIRS, MAP 1:1, 1000, 000. 4 SHEETS.South Africa, Lesotho, Swaziland, Southern AfricaGeology, Mineral Resources, Diamonds
DS1991-1067
1991
Martini, J.E.J.Martini, J.E.J.The nature, distribution and genesis of coesite and stishovite associated with the pseudotachylite of the Vredefort Dome, South AfricaEarth and Planetary Science Letters, Vol. 103, No. 1-4, April pp. 285-300South AfricaCoesite, Mineralogy
DS1993-0967
1993
Martin-Izard, A.Mangas, J., Perez-Torrado, F.J., Reguilon, R., Martin-Izard, A.Geological characteristics of alkaline rocks and carbonatites of Fuerteventura (Canary Islands, Spain) and their rare earth elements (REE) ore potential.Terra Abstracts, IAGOD International Symposium on mineralization related to mafic, Vol. 5, No. 3, abstract supplement p. 32.GlobalCarbonatite
DS201012-0609
2010
Martino, R.Ramos, V.A., Vukovich, G., Martino, R., Otamendi, J.Pampia: a large cratonic block missing in the Rodinia supercontinentJournal of Geodynamics, Vol. 50, 3-4, pp. 243-255.South AmericaCraton, crustal evolution
DS1996-0068
1996
Martino, R.D.Baldo, E.G., Martino, R.D.Evolution of the Sierras de Cordoba, ArgentinaTectonophysics, Vol. 267, No. 1-4, Dec. 30, pp. 121-142ArgentinaTectonics, Sierras de Cordoba region
DS1994-0235
1994
Martinod, J.Burg, J.P., Davy, P., Martinod, J.Shortening of analogue models of the continental lithosphere: new hypothesis for the formation Tibetan plateau.Tectonics, Vol. 13, No. 2, Apr. pp. 475-83.ChinaTectonics
DS2003-1150
2003
Martinod, J.Regard, V., Faccenna, C., Martinod, J., Bellier, O., Thomas, J-C.From subduction to collision: control of deep processes on the evolution of convergentJournal of Geophysical Research, Vol. 108, B4. 10.1029/2002JB001943MantleSubduction, Tectonics
DS200412-1647
2003
Martinod, J.Regard, V., Faccenna, C., Martinod, J., Bellier, O., Thomas, J-C.From subduction to collision: control of deep processes on the evolution of convergent plate boundary.Journal of Geophysical Research, Vol. 108, B4. 10.1029/2002 JB001943MantleSubduction Tectonics
DS2003-1225
2003
Martinotti, G.Schmid, R., Romer, R.L., Franz, L., Oberhansli, R., Martinotti, G.Basement cover sequences within the UHP unit of the Dabie ShanJournal of Metamorphic Geology, Vol. 21, 6, pp. 531-38.ChinaUHP
DS200412-1755
2003
Martinotti, G.Schmid, R., Romer, R.L., Franz, L., Oberhansli, R., Martinotti, G.Basement cover sequences within the UHP unit of the Dabie Shan.Journal of Metamorphic Geology, Vol. 21, 6, pp. 531-38.ChinaUHP
DS200612-1063
2006
Martinotti, G.Peccerillo, A., Martinotti, G.The western Mediterranean lamproitic magmatism: origin and geodynamic significance.Terra Nova, Vol. 18, 2, April pp. 109-117.EuropeMagmatism - lamproite
DS201112-0160
2011
MartinsChakmouradian, A.R., Bohm, Coeslan, Mumin, Reguir, Demeny, Simonetti, Kressall, Martins, Kamenov, Creaser, LepekhinaPostorogenic carbonatites: more abundant than we realize and more important than given credit for.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.17-19.Canada, ManitobaCinder Lake, Eden Lake, Paint Lake
DS201112-0161
2011
MartinsChakmouradian, A.R., Bohm, Coeslan, Mumin, Reguir, Demeny, Simonetti, Kressall, Martins, Kamenov, Creaser, LepekhinaPostorogenic carbonatites: more abundant than we realize and more important than given credit for.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.17-19.Canada, ManitobaCinder Lake, Eden Lake, Paint Lake
DS200512-0943
2005
Martins, A.Schmitz, M., Martins, A., Izarra, C., Jacome, M.I., Sanchez, J., Rocabado, V.The major features of the crustal structure in northeastern Venezuela from deep wide angle seismic observations and gravity modelling.Tectonophysics, Vol. 399, 1-4, April 27, pp. 109-124.South America, VenezuelaGeophysics - seismics, crustal structure, tectonics
DS201911-2518
2019
Martins, A.A.de Almeida Morales, B.A., de Almeida, D.D.P.M., Koester, E., da Rocha, A.M.R., Dorneles, N.T., da Rosa, M.B., Martins, A.A.Mineralogy, whole-rock geochemistry and C, O isotopes from Passo Feio carbonatite, Sul-Riograndense shield, Brazil.Journal of South American Earth Sciences, Vol. 94, 102208 13p. PdfSouth America, Brazilcarbonatite

Abstract: Carbonatites are peculiar igneous rocks, consisting mainly of greater than 50% carbonate minerals, which arouse an economic interest due to the potentiality of high phosphate content and Light Rare Earth Elements (LREE) associated with their occurrence. The Passo Feio Carbonatite (PFC) is located 17?km Southwest of Caçapava do Sul city and constitutes NW dipping body, which is interposed with Passo Feio Formation metamorphic rocks. The PFC varies texturally from massive to foliated, being mainly composed of calcites and dolomites and on a smaller scale by apatites, phlogopites and tremolites. The opaque minerals correspond to hematites, magnetites, pyrites and barites, while the accessory minerals are represented by zircons, monazites- (Ce) and aeschynites- (Ce). Probably those REE mineral phases correspond to a hydrothermal stage, with the REE remobilization from apatites into those latter REE-rich mineral phases - this hypothesis is corroborated by geochemistry, mineral chemistry and microtextures found. Considering the results of mineral chemistry and taking into account the textural criteria, it was possible to classify carbonatite as an alvikite, with geochemical patterns that do not indicate economic potential for REE. However, soil geochemistry showed an important enrichment in REE, reflecting a probable concentration of monazites- (Ce) and aeschynites- (Ce), and because of this, it was possible to establish a zone in which the Passo Feio Carbonatite would probably be extended. In the stable isotope analyzes, the ?13C values varied between ?4.14 and ?3.89‰ while those of ?18O between 10.01 and 11.32‰ which can be attributed to the cooling of the magma itself, without suggesting metamorphic processes or subsequent changes. The deformation found in this carbonatite was probably developed in late-magmatic conditions, guided by tectonics associated with horizontal movements in shear zones. Thus, this work suggests that this carbonatite was the product of the reactivation of mantle sources, within a post-collision magmatic context of the Sul-Riograndense Shield.
DS201012-0169
2010
Martins, J.C.Doucelance, R., Hammouda, T., Moreira, M., Martins, J.C.Geochemical constraints on depth of origin of oceanic carbonatites: The Cape Verde Case.Geochimica et Cosmochimica Acta, Vol. 74, 24, pp. 7261-7282.Europe, Cape Verde IslandsCarbonatite
DS1984-0234
1984
Martins, J.M.Dias Menzies Jr., L.A., Martins, J.M.The Jacupiranga Mine, Sao Paulo, BrasilThe Mineralogical Record., Vol. 15, No. 5, PP. 261-270.BrazilCarbonatite, History, Geology, Mineralogy
DS200812-0888
2008
Martins, M.Petrovsky, V.A., Silaev, V.I., Sukharev, A.E., Shamina, S.N., Martins, M., Karfunkel, J.Fluid phases in carbonado and their generic significance.Geochemistry International, Vol. 46, 7, pp. 693-710.TechnologyCarbonado
DS201012-0580
2010
Martins, M.Petrovsky, V.A., Shiryaev, A.A., Lyutoev, V.P., Sukharev, A.E., Martins, M.Morphology and defects in diamond grains in carbonado: clues to carbonado genesis.European Journal of Mineralogy, Vol. 22, 1, pp. 35-47..MantleDiamond morphology
DS201012-0581
2010
Martins, M.Petrovsky, V.A., Shiryaev, A.A., Lyutoev, V.P., Sukharev, A.E., Martins, M.Morphology and defects in diamond grains in carbonado: clues to carbonado genesis.European Journal of Mineralogy, Vol. 22, 1, pp. 35-47..MantleDiamond morphology
DS201012-0582
2009
Martins, M.Petrovsky, V.A., Silaev, V.I., Sukharev, A.E., Shanina, S.N., Martins, M., Karfunkel, J.Fluid phases in carbonado and their genetic significance.Geochemistry International, Vol. 47, 7, July, pp. 693-710.TechnologyCarbonado
DS201012-0768
2010
Martins, M.Sukharev, A.E., Petrovsky, V.A., Silaev, V.I., Martins, M.Solid inclusions in carbonados.International Mineralogical Association meeting August Budapest, abstract p. 186.TechnologyCarbonado
DS201112-0840
2010
Martins, M.Rakin, V.I., Petrovsky, V.A., Sukharev, A.E., Martins, M.Morphological crystallography of Brazilian diamonds.Vestnik Komi FAN, **in Russian copy available, No. 10, pp. 2-7.South America, BrazilDiamond morphology
DS201812-2849
2018
Martins, M.Martins, M.Carolina kimberlite and the exploration and potential of the Pimenta Bueno diamond District, Rondonia, Brazil.7th Symposio Brasileiro de Geologia do Diamante , Title only South America, Brazil, Rondoniadeposit - Carolina
DS200812-0890
2008
Martins, M.A.Petrovsky, V.A.A.A., Silaev, V.A.I.A., Martins, M.A., Karfunkel, J.A., Sukharev, A.A.E.A.Nanoscale mineral inclusions in the diamond phase of carbonados.Doklady Earth Sciences, Vol. 421, 2, pp. 889-892.TechnologyDiamond inclusions
DS201212-0124
2012
Martins, M.S.Chemale, F., Dussin, I.A., Alkmim, F.F., Martins, M.S., Queiroga, G., Armstrong, R., Santos, M.N.Unravelling a Proterozoic basin history through detrital zircon geochronology: the case of the Esponhaco Supergroup, Minas Gerais, Brazil.Gondwana Research, Vol. 22, 1, pp. 200-206.South America, Brazil, Minas GeraisSan Francisco Congo paleocraton, diamond bearing sequences
DS202005-0770
2020
Martins, M.V.C.Weska, R.K., Ferreira Barbosa, P., Martins, M.V.C., Souza, V.S., Dantas, E.L.Pectolite in the Carolina kimberlitic intrusion, Espigao D'Oeste - Rondonia, Brazil. ( Pimenta Bueno field)Journal of South American Earth Sciences, Vol. 100, 10.1016/j.jsames.2020.102583 7p. PdfSouth America, Brazil, Rondoniadeposit - Carolina

Abstract: In this study, we characterize pectolite that occurs in a Carolina kimberlitic intrusion from the Pimenta Bueno Kimberlite Field (PBKF). The PBKF is the only kimberlite field of Permo-Carboniferous age in Brazil and is found on the southern Amazonian Craton. Pectolite, an Na-Ca-silicate usually identified in alkaline rocks as a primary mineral, is not common in the mineral paragenesis of kimberlites and is described here for the first time in Brazil. The genesis of pectolite in kimberlite has been well-studied and can be interpreted as a primary or secondary mineral resulting from the infiltration of an Na-rich fluid into metasomatic reactions. In the rocks from the PBKF, pectolite mainly occurs as fibrous and radial aggregates enriched in K2O that grow between olivine partially altered to serpentine and phlogopite. The results of field and petrographic observations suggest that the PBKF pectolite is of secondary origin, having formed during the hydrothermal alteration of the Carolina kimberlitic intrusion.
DS201412-0555
2014
Martins, T.Martins, T., Chakhmouradian, A.R., Medici, L.Perovskite alteration in kimberlites and carbonatites: the role of kassite, CaTi204(OH)2.Physics and Chemistry of the Earth Parts A,B,C, Vol. 41, 6, pp. 473-484.MantleKimberlite
DS1991-1068
1991
Martins de Souza, .M.Martins de Souza, .M.Bibliografia sobre diamante na regiiao de Diamentina, MG.(in Portugese)Brasil Servico Publico Federal Ministerio da Infra-estrutera divisao de, 10p. (94 refs)BrazilBibliography, Diamantina area -diamonds/kimberlites
DS2000-0623
2000
Martins-Neto, M.A.Martins-Neto, M.A.Tectonics and sedimentation in a paleo-mesoproterozoic rift-sag basin ( Espinhaco Basin, southeastern Brasil).Precambrian Research, Vol. 103, pp. 147-73.BrazilCraton - San Francisco, Diamantina area - not diamonds
DS200612-1517
2005
Martinsson, O.Weihed, P., Arndt, N., Billstrom, K., Duschesne, J-C., Eilu, P., Martinsson, O., Papunen, H., Lahtinen, R.Precambrian geodynamics and ore formation: the Fennoscandian shield.Ore Geology Reviews, Vol. 27, pp. 273-322.Europe, FennoscandiaMetallogeny - tectonics
DS201903-0531
2019
Martirosayan, N.S.Martirosayan, N.S., Shatskiy, A., Chanyshev, A.D., Litasov, K.D., Podborodnikov, I.V., Yoshino, T.Effect of water on the magnesite-iron interaction, with implications for the fate of carbonates in the deep mantle.Lithos, Vol. 326-327, pp. 435-445.Mantleperidotite

Abstract: The subduction of carbonates beyond 250-300?km, where redox conditions favour the presence of metallic iron (Fe), will result in redox reactions with the Fe dispersed in the silicate rocks. Here, we studied the effect of water on the carbonate-Fe interaction in the hydromagnesite-Fe system at 6, 8 and 16?GPa and the peridotite-CO2-H2O-Fe system at 8?GPa, using a multianvil apparatus. In all of the studied samples, we observed the formation of magnesiowüstite, graphite and carbide. Additionally, in the peridotite-CO2-H2O-Fe system, magnesiowüstite reacted with pyroxenes, resulting in olivine enrichment. Kinetic calculations performed at 8?GPa showed that, at the pressure-temperature (P-T) parameters of the ‘hot’, ‘medium’ and ‘cold’ subduction, about 40, 12 and 4?vol% of carbonates, respectively, would be reduced in the hydrous system within 1 Myr, assuming direct contact with Fe. Based on the present results, it is suggested that carbonates will largely be consumed during the characteristic subduction time to the mantle transition zone by reaction with the reduced mantle in the presence of hydrous fluid.
DS201412-0556
2014
Martirosyan, N.Martirosyan, N., Yoshino, T., Shatskiy, A., Chanyshev, A., Litasov, K.Kenetic study of Ca- carbonate - iron interaction. ( global geodynamic processes - diamond formation)V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept 22-26, 2p. AbstractMantleGeodynamics
DS201412-0557
2014
Martirosyan, N.Martirosyan, N., Yoshino, T., Shatskiy, A., Chanyshev, A., Litasov, K.Effect of water on the stability of magnesite in the mantle under reduced conditions.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 2p. AbstractMantleWater
DS201902-0296
2019
Martirosyan, N.S.Martirosyan, N.S., Shatskiy, A., Chanyshev, A.D., Litasov, K.D., Yoshino, T.Effect of water on the magnesium iron interaction, with implications for the fate of carbonates in the deep mantleLithos, Vol. 326-327, pp. 572-585.Mantlewater
DS201907-1560
2019
Martirosyan, N.S.Martirosyan, N.S., Litasov, K.D., Lobanov, S.S., Goncharov, A.F., Shatskiy, A., Ohfuji, H., Prakapenka, V.The Mg carbonate Fe interaction: implication for the fate of subducted carbonates and formation of diamond in the lower mantle.Geoscience Frontiers, Vol. 10, pp. 1449-1458.Mantlecarbon cycle

Abstract: The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe0 system at 70-150 GPa and 800-2600 K in a laser-heated diamond anvil cell. Using in situ synchrotron X-ray diffraction and ex situ transmission electron microscopy we show that the reduction of Mg-carbonate can be exemplified by: 6MgCO3 + 19Fe = 8FeO +10(Mg0.6Fe0.4)O + Fe7C3 + 3C. The presented results suggest that the interaction of carbonates with Fe0 or Fe0-bearing rocks can produce Fe-carbide and diamond, which can accumulate in the D’’ region, depending on its carbon to Fe ratio. Due to the sluggish kinetics of the transformation, diamond can remain metastable at the core-mantle boundary (CMB) unless it is in a direct contact with Fe-metal. In addition, it can be remobilized by redox melting accompanying the generation of mantle plumes.
DS202105-0776
2021
Martirosyan, N.S.Martirosyan, N.S., Efthimiopoulos, I., Pennacchioni, L., Wirth, R., Jahn, S., Koch-Muller, M.Effect of catonic substitution on the pressure -induced phase transition in calcium carbonate.American Mineralogist, Vol. 106, pp. 549-558. pdfMantledeep carbon cycle
DS1859-0039
1828
Martius, C.F.P. VON.Spix, J.B.VON, Martius, C.F.P. VON.Reise in BrasilienMuenchen: Lentner., 2 VOLS., 885P., ( DIAMONDS Brasil Vol. 2, PP. 429-484 ). XERBrazilTravelogue
DS2001-0806
2001
MartonMosenfelder, J.L., Marton, Ross, Kerschhofer, RubieExperimental constraints on the depth of olivine metastability in subducting lithospherePhysics of the Earth and Planetary Interiors, Vol. 127, No. 1-4, Dec. 1, pp. 165-80.MantleMineralogy - olivine, Subduction - geodynamics, rheology
DS1997-0740
1997
Marton, E.Marton, E.Paleomagnetic aspects of plate tectonics in the Carpatho-Pannonian regionMineralium Deposita, Vol. 32, No. 5, pp. 441-445HungaryPaleomagnetism, Tectonics
DS1999-0445
1999
Marton, F.C.Marton, F.C., Bina, C.R., Rubie, D.C.Effects of slab mineralogy on subduction ratesGeophysical Research Letters, Vol. 26, No. 2, Jan. 15, pp. 199-22.MantleSubduction, Mineralogy - slabs
DS2001-0111
2001
Marton, F.C.Bina, C.R., Stein, S., Marton, F.C., Van Ark, E.M.Implications of slab mineralogy for subduction dynamicsPhysics of the Earth and Planetary Interiors, Vol. 127, No. 1-4, Dec. 1, pp. 51-66.MantleMineralogy - slab, Subduction - geodynamics
DS2001-0734
2001
Marton, F.C.Marton, F.C., Ita, J., Cohen, R.E.Pressure volume temperature equation of state of MgSiO3 perovskite from molecular dynamics and constraints....Journal of Geophy. Res., Vol. 106, No. 5, May 10, pp. 8715-28.MantleComposition - mineralogy
DS2002-1000
2002
Marton, F.C.Marton, F.C., Cohen, R.E.Constraints on lower mantle composition from molecular dynamics simulations of MgSiO3 perovskite.Physics of the Earth and Planetary Interiors, Vol. 134, 3-4, Dec. 22, pp. 239-52.MantleGeophysics - seismics
DS200712-0968
2007
Marton, F.C.Sharp, T.G., Diedrich, T., Marton, F.C., DuFrane, W.Subduction of hydrated lithosphere: 300 ppm H2O in subducting olivine would eliminate the metastable olivine wedge.Plates, Plumes, and Paradigms, 1p. abstract p. A923.MantleSubduction
DS201312-0580
2013
Martorell, B.Martorell, B., Vocadlo, L., Brodholt, J., Wood, I.G.Strong premelting effect in the elastic properties of hcp-Fe under inner core conditions.Science, Vol. 342, 6157, pp. 466-468.MantleCore, melting
DS201811-2593
2018
Martos, Y.M.Martos, Y.M., Jordan, T.A., Catalan, M., Jordan, T.M., Bamber, J.L., Vaughan, D.G.Geothermal heat flux reveals the Iceland hotspot track underneath Greenland.Geophysical Research Letters, Vol. 45, 16, pp. 8214-8222.Europe, Greenlandplumes

Abstract: Heat escaping from the Earth's interior provides important clues about areas of geology and geodynamics. In addition, where a region is covered by an ice sheet, such as Greenland, variations in the heat supplied from the Earth's interior can potentially influence how the ice flows, and hence its future changes. Unfortunately, in ice covered regions direct measurements of heat flow are limited to sparse boreholes, meaning this important quantity is poorly understood. In this study we used variations in the Earth's magnetic field to map out the variations in the amount of heat being supplied to the base of the Greenland Ice Sheet from the Earth's interior. Ice sheet models incorporating these new and improved results will help better constrain future predictions of ice sheet evolution. Overall, the new map not only shows less extreme variations than previous studies, but also reveals a previously unseen band of warmer than expected rock stretching northwest to southeast across Greenland. This band, together with lithospheric models derived from gravity data, is interpreted to be the scar left as the Greenland tectonic plate moved over a region of hot upwelling mantle (the material beneath the tectonic plates), which now underlies Iceland.
DS1987-0439
1987
Martovitskii, V.P.Martovitskii, V.P., Nadezhdina, E.D., Ekimova, T.E.Internal structure and morphology of small nonkimberliticdiamonds.(Russian)Mineral Zhurn., (Russian), Vol. 9, No. 2, pp. 26-37GlobalBlank
DS1982-0481
1982
Martovitskiy, V.P.Orlov, YU.L., Bulen'kov, N.A., Martovitskiy, V.P.Spheroid Diamond Crystals- a New Type of Fibrous Natural Single Crystals.Doklady Academy of Science USSR, Earth Science Section., Vol. 252, No. 1-6, PP. 117-120.RussiaCrystallography
DS1985-0417
1985
Martovitskiy, V.P.Martovitskiy, V.P., Bulyenkov, N.A., et al.Characteristics of the Internal Structure of Ballas Diamonds. (russian)Izvest. Akad. Nauk SSSR, ser. geol., (Russian), No. 6, pp. 71-77RussiaCrystallography, Diamond
DS1985-0418
1985
Martovitskiy, V.P.Martovitskiy, V.P., Solodova, Y.P.The internal structure and morphology of penetrating twins ofnaturaldiamond.(Russian)Mineral. Zhurn., (Russian), Vol. 7, No. 5, pp. 40-50RussiaDiamond Morphology
DS1985-0419
1985
Martovitskiy, V.P.Martovitskiy, V.P., Zadnerprovskiy, B.I., Bulenko, N.A.The internal structure of synthetic diamonds with thread likeinclusions.(Russian)Kristallografiya, (Russian), Vol. 30, No. 6, pp. 1203-1206RussiaSynthetic Diamonds, Diamond Morphology
DS1982-0482
1982
Martovitsky, V.P.Orlov, YU.L., Bulienkov, N.A., Martovitsky, V.P.A Study of the Internal Structure of Variety Iii Diamonds By X-ray Section Topography.Physics And Chemistry of Minerals, Vol. 8, No. 3, PP. 105-111.RussiaMineralogy, Crystallography
DS1987-0440
1987
Martovitsky, V.P.Martovitsky, V.P., Nedezhdina, Y.D., Yekimova, T.Y.Internal structure and morphology of small non-kimberlitediamonds.(Russian)Mineralog. Zhurnal, (Russian), Vol. 9, No. 2, April pp. 26-37RussiaCrystallography
DS200612-1020
2006
Martovitsky, V.P.Orlov, Y.L., Bulienkov, N.A., Martovitsky, V.P.A study of the internal structure of variety III diamonds by X-ray section topography.Physics and Chemistry of Minerals, Vol. 8, 3, pp. 105-111.TechnologyDiamond morphology
DS2002-1605
2002
MartyTolstikhin, I.N., Kamensky, Marty, Nivin, Vetrin et al.Rare gas isotopes and parent trace elements in ultrabasic alkaline carbonatite complexes, Kola Peninsula.Geochimica et Cosmochimica Acta, Vol. 66, No. 5, pp. 881-901.Russia, Kola PeninsulaMantle plume component, Geochemistry
DS1987-0441
1987
Marty, B.Marty, B., Jambon, A.C/3He in volatile fluxes from the solid earth: implications for carbongeodynamicsEarth and Planetary Science Letters, Vol. 83, No. 1-4, May pp. 16-26GlobalGeochemistry
DS1995-0297
1995
Marty, B.Chaussidon, M., Marty, B.Primitive boron isotope composition of the mantleScience, Vol. 269, July 21, pp. 383-6.MantleGeochemistry, Mid Ocean Ridge Basalt (MORB) - not specific to diamonds
DS1995-0298
1995
Marty, B.Chaussidon, M., Marty, B.Primitive boron isotope composition of the mantleScience, Vol. 269, July 21, pp. 383-386MantleGeochronology -boron, Morbs
DS1995-1173
1995
Marty, B.Marty, B.Nitrogen content of the mantle inferred from N2 Argon correlation in oceanic basaltsNature, Vol. 377, No. 6547, Sept. 28, pp. 326-329MantleBasalts, Nitrogen
DS1996-1183
1996
Marty, B.Richard, D., Marty, B., Chaussidon, M., Arndt, N.Helium isotope evidence for a lower mantle component in depleted ArcheankomatiiteScience, Vol. 273, July 5, pp. 93-94Mantle, Ocean Island BasaltsKomatiite, Geochronology
DS1996-1184
1996
Marty, B.Richard, D., Marty, B., Chaussidon, M., Arndt, N.Helium isotopic evidence for a lower mantle component in depleted ArcheankomatiiteScience, Vol. 273, July 5, pp. 93-95OntarioKomatiites, Deposit -Alexo
DS1998-0950
1998
Marty, B.Marty, B., Tolstikhin, I., Zimmermann, J.L.Plume derived rare gases in 380 Ma carbonatites from the Kola region And the argon isotopic composition...Earth and Planetary Science Letters, Vol.164, No.1-2, Dec.15, pp.179-92.Russia, Kola PeninsulaMantle chemistry, geochronology, Carbonatite
DS1998-0951
1998
Marty, B.Marty, B., Upton, B.G., Ellam, R.M.Helium isotopes in early Tertiary basalts, northeast Greenland: evidence for 59 Ma plume activity ...Geology, Vol. 26, No. 5, May pp. 407-410.GlobalMagmatism, plumes, Geochronology
DS1998-1283
1998
Marty, B.SaNo. Y., Takahata, N., Marty, B.Nitrogen recycling in subduction zonesGeophysical Research. Letters, Vol. 25, No. 13, Jul. 1, pp; 2289-92.MantleSubduction
DS2003-0818
2003
Marty, B.Libourel, G., Marty, B., Humbert, F.Nitrogen solubility in basaltic melt. Part 1. Effect of oxygen fugacityGeochimica et Cosmochimica Acta, Vol. 67, 21, Nov. 1, pp. 4123-35.GlobalPetrology - magma
DS2003-0879
2003
Marty, B.Marty, B., Dauphas, N.The nitrogen record of crust mantle interaction and mantle convection from Archean toEarth and Planetary Science Letters, Vol. 206, No. 3-4, pp. 397-410.MantleConvection
DS200412-0410
2004
Marty, B.Dauphas, N., Marty, B.A large secular variation in the nitrogen isotopic composition of the atmosphere since the Archean .. response to a comment on tEarth and Planetary Science Letters, Vol. 225, 3-4, pp. 435-440.MantleGeochronology, nitrogen
DS200412-1136
2003
Marty, B.Libourel, G., Marty, B., Humbert, F.Nitrogen solubility in basaltic melt. Part 1. Effect of oxygen fugacity.Geochimica et Cosmochimica Acta, Vol. 67, 21, Nov. 1, pp. 4123-35.TechnologyPetrology - magma
DS200412-2183
2004
Marty, B.Yokochi, R., Marty, B.A determination of the neon isotopic composition of the deep mantle.Earth and Planetary Science Letters, Vol. 225, 1-2, pp. 77-88.MantleGeochronology
DS200512-0060
2005
Marty, B.Ballentine, C.J., Marty, B., Lollar, B.S., Cassidy, M.Neon isotopes constrain convection and volatile origin in the Earth's mantle.Nature, no. 7021, Jan. 6, pp. 33-38.MantleGeochronology
DS200612-0080
2006
Marty, B.Ballentine, C., Asimov, P., Hirschmann, M., Marty, B.Volatiles in the mantle.Goldschmidt Conference 16th. Annual, S4-07 theme abstract 1/8p. goldschmidt2006.orgMantleGeochemistry
DS200612-0200
2006
Marty, B.Burnard, P., Basset, R., Marty, B., Fischer, T., Palhol, F., Mangasini, F., Makene, C.Xe isotopes in carbonatites: Oldonyo Lengai, East African Rift.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.Africa, TanzaniaCarbonatite
DS200612-1088
2005
Marty, B.Pik, R., Marty, B., Hilton, D.R.How many mantle plumes in Africa? The geochemical point of view.Chemical Geology, Vol. 226, 3-4, pp. 100-114.AfricaAfrican plate, Hoggar, Tibesti, Darfur, Ethiopia, Kenya
DS200812-0761
2007
Marty, B.Montagner, J.P., Marty, B., Stutzmann, E., Sicilia, D., Cara, M., Pik, R., Leveque, Roult, Beucier, DeBayleMantle upwellings and convective instabilities revealed by seismic tomography and helium isotope geochemistry beneath eastern Africa.Geophysical Research Letters, Vol. 34, 21, Nov. 16, ppp. L21303.AfricaConvection
DS201112-0832
2011
Marty, B.Pujol, M., Marty, B., Burgess, R.Chondritic like xenon trapped in Archean rocks: a possible signature of the ancient atmosphere.Earth and Planetary Science Letters, Vol. 308, 3-4, pp. 298-306.MantleGeochronology
DS201312-0128
2013
Marty, B.Cartigny, P., Marty, B.Nitrogen and its (Biogeocosmo) chemical cycling: nitrogen isotopes and mantle geodynamics: the emergence of life and the atmosphere-crust-mantle connection.Elements, Vol. 9, pp. 359-366.TechnologyNitrogen
DS201312-0581
2013
Marty, B.Marty, B., Zimmermann, L., Pujol, M., Burgess, R., Philippot, P.Nitrogen isotopic composition and density of the Archean atmosphere.Science, Vol. 342, 6154, pp. 101-104.MantleVolatiles
DS201709-2034
2017
Marty, B.Mollex, G., France, L., Furi, E., Bonnet, R., Botcharnikov, R.E., Zimmermann, L., Wilke, S., Deloule, E., Chazot, G., Kazimoto. E.O., Marty, B., Burnard, P.The Oldoinyo Lengai volcano plumbing system architecture, and composition from source to surface.Goldschmidt Conference, abstract 1p.Africa, Tanzaniadeposit, Oldoinyo

Abstract: Cognate xenoliths that have been emitted during the last sub-plinian eruption in 2007-08 at Oldoinyo Lengai (OL) represent a unique opportunity to document the igneous processes occuring within the active magma chamber. Detailed petrographic descriptions coupled to a thermobarometric approach, and to the determination of volatile solubility models, allow us to identify the melt evolution at magma chamber conditions, and the storage parameters (P, T). Results indicate that a fresh phonolite melt (~1060°C) was injected into a crustal magma chamber at 11.5 ±3.5 km depth, in agreement with geophysical surveys performed during the eruption. The phonolite contains high volatile contents: 3.2 wt.% H2O and 1.4 wt.% CO2. The liquid line of descent highlights an evolution to nephelinite compositions by cooling down to 880°C. Our results support previous results related to this eruption, and are similar to the historical products emitted during the whole volcano history, allowing us to suggest that no major modification in the plumbing system has occured during the OL evolution. New noble gas results show that: i. fumaroles display constant He isotopic signature since 1988; ii. Cognate xenoliths documenting the active magma chamber and fumaroles display similar He isotopic values (6.58±0.46RA, and 7.31±0.40RA, respectively); iii. OL He isotopic composition is similar to that of other silicate volcanoes of the Arusha region, and comparable to the typical subcontinental lithospheric mantle (SCLM) range (5.2 to 7.0 RA); iv. Ne isotopic ratio of OL is following the MORB signature. Those results are interpreted as showing that 1/ no major modification in the hydrothermal system architecture has occured since 1988 despite major modification of the summit crater morphology, 2/ no contamination by either the atmospheric gases, or crustal material assimilation has occured between the magma chamber and the surface, and 3/ the source of OL and of the other silicate volcanoes in the Arusha region is a SCLM metasomatized by asthenospheric fluids.
DS201808-1724
2018
Marty, B.Avice, G., Marty, B., Burgess, R., Hofmann, A., Philippot, P., Zahnle, K., Zakharov, D.Evolution of atmospheric xenon and other noble gases inferred from Archean to Paleoproterozoic rocks.Geochimica et Cosmochimica Acta, Vol. 232, pp. 82-100.Mantlegeochemistry

Abstract: We have analyzed ancient atmospheric gases trapped in fluid inclusions contained in minerals of Archean (3.3?Ga) to Paleozoic (404?Ma) rocks in an attempt to document the evolution of the elemental composition and isotopic signature of the atmosphere with time. Doing so, we aimed at understanding how physical and chemical processes acted over geological time to shape the modern atmosphere. Modern atmospheric xenon is enriched in heavy isotopes by 30-40‰ u?1 relative to Solar or Chondritic xenon. Previous studies demonstrated that, 3.3?Ga ago, atmospheric xenon was isotopically fractionated (enriched in the light isotopes) relative to the modern atmosphere, by 12.9?±?1.2 (1?) ‰ u?1, whereas krypton was isotopically identical to modern atmospheric Kr. Details about the specific and progressive isotopic fractionation of Xe during the Archean, originally proposed by Pujol et al. (2011), are now well established by this work. Xe isotope fractionation has evolved from 21‰ u?1 at 3.5?Ga to 12.9‰ u?1 at 3.3?Ga. The current dataset provides some evidence for stabilization of the Xe fractionation between 3.3 and 2.7?Ga. However, further studies will be needed to confirm this observation. After 2.7?Ga, the composition kept evolving and reach the modern-like atmospheric Xe composition at around 2.1?Ga ago. Xenon may be the second atmospheric element, after sulfur, to show a secular isotope evolution during the Archean that ended shortly after the Archean-Proterozoic transition. Fractionation of xenon indicates that xenon escaped from Earth, probably as an ion, and that Xe escape stopped when the atmosphere became oxygen-rich. We speculate that the Xe escape was enabled by a vigorous hydrogen escape on the early anoxic Earth. Organic hazes, scavenging isotopically heavy Xe, could also have played a role in the evolution of atmospheric Xe. For 3.3?Ga-old samples, Ar-N2 correlations are consistent with a partial pressure of nitrogen (pN2) in the Archean atmosphere similar to, or lower than, the modern one, thus requiring other processes than a high pN2 to keep the Earth's surface warm despite a fainter Sun. The nitrogen isotope composition of the atmosphere at 3.3?Ga was already modern-like, attesting to inefficient nitrogen escape to space since that time.
DS201912-2803
2019
Marty, B.Marty, B., Bekaert, D.V., Broadley, Jaupart, C.Geochemical evidence for high volatile fluxes from the mantle at the end of the Archean. (water, carbon dioxide, nitrogen and halogens)Nature, Vol. 575, pp. 485-488.Mantlemelting, convection

Abstract: The exchange of volatile species—water, carbon dioxide, nitrogen and halogens—between the mantle and the surface of the Earth has been a key driver of environmental changes throughout Earth’s history. Degassing of the mantle requires partial melting and is therefore linked to mantle convection, whose regime and vigour in the Earth’s distant past remain poorly constrained1,2. Here we present direct geochemical constraints on the flux of volatiles from the mantle. Atmospheric xenon has a monoisotopic excess of 129Xe, produced by the decay of extinct 129I. This excess was mainly acquired during Earth’s formation and early evolution3, but mantle degassing has also contributed 129Xe to the atmosphere through geological time. Atmospheric xenon trapped in samples from the Archaean eon shows a slight depletion of 129Xe relative to the modern composition4,5, which tends to disappear in more recent samples5,6. To reconcile this deficit in the Archaean atmosphere by mantle degassing would require the degassing rate of Earth at the end of the Archaean to be at least one order of magnitude higher than today. We demonstrate that such an intense activity could not have occurred within a plate tectonics regime. The most likely scenario is a relatively short (about 300 million years) burst of mantle activity at the end of the Archaean (around 2.5 billion years ago). This lends credence to models advocating a magmatic origin for drastic environmental changes during the Neoarchaean era, such as the Great Oxidation Event.
DS202005-0744
2020
Marty, B.Labidi, J., Barry, P.H., Bekaert, D.V., Broadley, M.W., Marty, B., Giunta, T., Warr, O., Sherwood Lollar, B., Fischer, T.P., Avice, G., Caracusi, A., Ballentine, C.J., Halldorsson, S.A., Stefansson, A., Kurz, M.D., Kohl, I.E., Young, E.D.Hydrothermal 15N15N abundances constrain the origins of mantle nitrogen.Nature, Vol. 580, 7803 pp. 367-371. Mantlenitrogen

Abstract: Nitrogen is the main constituent of the Earth’s atmosphere, but its provenance in the Earth’s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth’s accretion versus that subducted from the Earth’s surface is unclear1,2,3,4,5,6. Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare 15N15N isotopologue of N2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle ?15N (the fractional difference in 15N/14N from air), N2/36Ar and N2/3He. Our results show that negative ?15N values observed in gases, previously regarded as indicating a mantle origin for nitrogen7,8,9,10, in fact represent dominantly air-derived N2 that experienced 15N/14N fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the 15N15N data allow extrapolations that characterize mantle endmember ?15N, N2/36Ar and N2/3He values. We show that the Eifel region has slightly increased ?15N and N2/36Ar values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts11, consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has ?15N values substantially greater than that of the convective mantle, resembling surface components12,13,14,15, its N2/36Ar and N2/3He ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume ?15N values may both be dominantly primordial features.
DS2002-1001
2002
Martynov, Y.A.Martynov, Y.A., Chaschin, Rasskazov, SaraninaLate Miocene Pliocene basaltic volcanism in the south of the Russian far East as an indicator of ...Petrology, Vol.10,2,pp.165-83.RussiaLithospheric mantle, heterogeneity continent-ocean
DS200512-0805
2005
Martynov, Y.A.Okamura, S., Arculus, R.J., Martynov, Y.A.Cenozoic magmatism of the north eastern Eurasian margin: the role of lithosphere versus asthenosphere.Journal of Petrology, Vol. 46, no. 2, pp. 221-253.Europe, Baltic ShieldMagmatism - not specific to diamonds
DS2002-1002
2002
Martynov, Yu.A.Martynov, Yu.A., Chaschin, Rasskazov, SaraniniaLate Miocene- Pliocene basaltic volcanism in the south of Russia Far East, an indicator of lithospheric mantlePetrology, Vol. 10, 2, pp. 165-83.Russia, Far EastHeterogeneity in continent - ocean transition zone
DS1970-0754
1973
Martynova, M.V.Martynova, M.V.Precious Stones (1973)Moscow: Iskusstvo, 45P.RussiaKimberley
DS201502-0102
2015
Martynovich, E.F.Skuzovatov, S.Yu., Zedgenizov, D.A., Rakevich, A.L., Shatsky, V.S., Martynovich, E.F.Multiple growth events in diamonds with cloudy Micro inclusions from the Mir kimberlite pipe: evidence from the systematics of optically active defects.Russian Geology and Geophysics, Vol. 56, 1, pp. 330-343.RussiaDeposit - Mir
DS201507-0328
2015
Martynovich, E.F.Mironov, V.P., Rakevich, A.L., Stepanov, F.A., Emelyanova, A.S., Zedgenizov, D.A., Shatsky, V.S., Kagi, H., Martynovich, E.F.Luminescence in diamonds of the Sao Luiz placer ( Brazil).Russian Geology and Geophysics, Vol. 56, pp. 729-736.South America, BrazilDiamond luminesence
DS201603-0423
2016
Martynovich, E.F.Stepanov, F.A., Mironov, V.P., Rakevich, A.L., Shatsky, V.S., Zedgenizov, D.A., Martynovich, E.F.Red luminescence decay kinetics in Brazilian diamonds. ( Juina)Bulletin of the Russian Academy of Sciences. Physics ** IN ENG, Vol. 80, 1, pp. 74-77.South America, BrazilDiamond formation

Abstract: Luminescence kinetics in the temperature range of 80 480 K and the red region of the spectrum is studied for Brazilian diamonds. Components with decay time constants of 23 and 83 ns are observed at room temperature after being excited by laser radiation with wavelengths of 375 and 532 nm, which differs considerably from the data published earlier for the luminescence kinetics of NV 0- and NV -centers.
DS201112-0811
2011
Martyushov, S.Yu.Polyakov, S.N., Denisov, V.N., Kuzmin, N.V., Kuznetsov, M.S., Martyushov, S.Yu., Nosukhin, Terentiev, BlankCharacterization of top quality type IIa synthetic diamonds for new x-ray optics.Diamond and Related Materials, Vol. 20, no. 5-6m pp. 726-728.TechnologyDiamond - synthesis applications
DS1992-0964
1992
Maruechevm A.M.Lukyanova, L.I., Maruechevm A.M., Mashchakov, A.M., et al.The first findings of the Lamproite magmatism manifestations on the southUrals.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 324, No. 6, pp. 1187-1190.RussiaLamproite
DS200412-1234
2004
Maruoka, T.Maruoka, T., Kurat, G., Dobosi, G., Koeberl, C.Isotopic composition of carbon in diamonds of diamondites: record of mass fractionation in the mantle.Geochimica et Cosmochimica Acta, Vol.68, 7, pp. 1635-1644.MantleGeochronology
DS200612-0880
2006
Maruoka, T.Matsumoto, T., Maruoka, T., Matsuda, J-I., Shimoda, G., Yamamoto, K., Morishita, T., Arai, S.Isotopic compositions of noble gas and carbon in the Archean carbonatites from the Sillinjarvi mine, central Finland.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 21, abstract only.Europe, FinlandCarbonatite, geochronology
DS1930-0258
1937
Marus And CoMarus And CoThe Story of the Diamond (1937)New York: Marcus And Co., 25P.GlobalKimberlite
DS2001-0581
2001
MaruyamaKatayama, I., Maruyama, Parkinson, Terada, SanoIon micro probe uranium-lead (U-Pb) zircon geochronology of peak and retrograde stages of ultrahigh pressure metamorphic...Earth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.185-198.Russia, KazakhstanGeochronology - ultra high pressure (UHP), Kokchetav Massif
DS2001-0694
2001
MaruyamaLiu, J., Ye, K., Maruyama, Cong, FanMineral inclusions in zircon from gneisses in the ultrahigh pressure zone of the Dabie Mountains.Journal of Geology, Vol. 109, pp. 523-35.Chinaultra high pressure (UHP), geochronology, Dabie Shan area
DS2001-1066
2001
MaruyamaShimizu, K., Komiya, T., Hirose, K., Shimizu, Maruyamachromium spinel an excellent micro container for retaining primitive melts - implications for a hydrous plume ...Earth and Planetary Science Letters, Vol. 189, No. 3-4, July 15, pp. 177-88.Zimbabwe, MantleKomatiites, Melting - Belingwe Greenstone belt
DS2002-0957
2002
MaruyamaLiu, F., Xu, Z., Liu, J.G., Katayama, Masago, Maruyama, YangUltra high pressure mineral inclusions in zircons from gneissic core samples of the Chinese continental drilling site in eastern China.European Journal of Mineralogy, No. 3, pp. 499-512.China, easternUHP, Mineral inclusions
DS1990-0765
1990
Maruyama, S.Jing, Y., Pan, G., Xia, M., Wang, X., Liou, J.G., Maruyama, S.Petrology of coesite bearing eclogites from the Dabie Mountains CentralChinaInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 864-865ChinaEclogites, Coesite
DS1990-0937
1990
Maruyama, S.Liou, J.G., Maruyama, S., Wang, X., Graham, S.Precambrian blueschist terranes of the worldTectonophysics, Vol. 181, pp. 97-111Alaska, Scandinavia, ChinaTerranes, Blueschist
DS1991-1249
1991
Maruyama, S.Oh, C.W., Liou, J.G., Maruyama, S.Low temperature eclogites and eclogitic schists in Mn-rich metabasites in Ward Creek, California: Mn and iron effects on the transition blueschist andeclogitesJournal of Petrology, Vol. 32, No. 2, April pp. 275-302CaliforniaEclogites
DS1994-0556
1994
Maruyama, S.Fukao, Y., Maruyama, S., Obayashi, M., Inoue, H.Geologic implication of the whole mantle P wave tomographyJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 4-23MantleTomography, Geophysics -seismics
DS1994-0557
1994
Maruyama, S.Fukao, Y., Maruyama, S., Obayashi, M., Inoue, H.Geologic implication of the whole mantle P wave tomographyJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 4-23.MantleTomography, Geophysics -seismics
DS1994-0962
1994
Maruyama, S.Kumazawa, M., Maruyama, S.Whole earth tectonicsJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 81-102MantleTectonics, Plumes
DS1994-0963
1994
Maruyama, S.Kumazawa, M., Maruyama, S.Whole earth tectonicsJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 81-102.MantleTectonics, Plumes
DS1994-1117
1994
Maruyama, S.Maruyama, S.Plume tectonicsJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 24-49MantleTectonics, Hot spots
DS1994-1118
1994
Maruyama, S.Maruyama, S.Plume tectonicsJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 24-49.MantleTectonics, Hot spots
DS1994-1119
1994
Maruyama, S.Maruyama, S., Kumazawa, M., Kawakami, S.Towards a new paradigm on the earth's dynamicsJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 1-3MantleGeodynamics
DS1994-1120
1994
Maruyama, S.Maruyama, S., Kumazawa, M., Kawakami, S.Towards a new paradigm on the earth's dynamicsJournal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 1-3.MantleGeodynamics
DS1998-0876
1998
Maruyama, S.Liou, J.G., Zhang, R.Y., Maruyama, S.high pressure minerals from deeply subducted metamorphic rocksReviews in Mineralogy, Vol. 37, pp. 33-96.MantleSubduction, Mineralogy
DS2000-0624
2000
Maruyama, S.Maruyama, S.The role of mantle water on the formation of superplumeGeological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-314.MantleSubduction
DS2001-0461
2001
Maruyama, S.Hayashi, M., Komiya, T., Nakamura, Y., Maruyama, S.Archean regional metamorphism Isua supracrustal belt: implications for a driving force for Archean plate..International Geology Review, Vol. 42, No. 12, Dec. pp. 1055-1115.Greenland, southwestTectonics, metamorphism
DS2002-0872
2002
Maruyama, S.Komiya, T., Maruyama, S., Hirata, T., Yurimoto, H.Petrology and geochemistry of MORB and OIB in the mid-Archean north pole regionInternational Geology Review, Vol. 44, No. 11, Nov. pp. 988-1016.Australia, westernMantle - geochronology
DS2002-1172
2002
Maruyama, S.Ogasawara, Y., Ohta, M., Fukasawa, K., Katayama, I., Maruyama, S.Petrology of diamond bearing dolomite marble from Kumdy KolFrontiers Science Series, University Academy Press, Vol. 38, pp. 191-212.ChinaPetrology
DS2002-1761
2002
Maruyama, S.Ye, K., Liu, J-B., Cong, B-L., Ye, D-N., Xu, P., Omori, S., Maruyama, S.Ultrahigh pressure (UHP) low Al titanites from carbonate bearing rocks in the Dabie shan Sulu UHP terrane, eastern China.American Mineralogist, Vol. 87, pp. 875-881.ChinaUHP - mineralogy, Dabie Shan area
DS2003-0693
2003
Maruyama, S.Katayama, I., Muko, A., Izuka, T., Maruyama, S., Terada, K., Tsutsumi, Y.Dating of zircon from Ti clinohumite bearing garnet peridotite: implication for timing ofGeology, Vol. 31, 8, pp. 713-716.MantleGeochronology
DS2003-0880
2003
Maruyama, S.Maruyama, S.The western Pacific triangular zone: frontier to form a future supercontinentGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p. 428.Pacific OceanSubduction - not specific to diamonds
DS2003-0881
2003
Maruyama, S.Maruyama, S.Significance of UHP mineralogy in collisional belt: insight from the Kokchetav MassifGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.227.Russia, KazakhstanUHP
DS2003-0882
2003
Maruyama, S.Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate referred from eclogite xenoliths in the ColoradoGeology, Vol. 31, 7, July pp. 589-92.Colorado PlateauCoesite, zircon, geochronology
DS2003-0883
2003
Maruyama, S.Maruyama, S., Parkinson, C.D., Liou, J.G.Overview of the tectonic evolution of the Kokchetav Massif and the role of fluid inFrontiers Science Series, University Academy Press, Vol. 38, pp. 427-42.RussiaTectonics
DS2003-0885
2003
Maruyama, S.Masago, H., Rumble, D., Ernst, W.G., Parkinson, C.D., Maruyama, S.Low delta 8 O eclogites from the Kokchetav Massif, northern KazakhstanJournal of Metamorphic Geology, Vol. 21, 6, pp. 579-88.Russia, KazakhstanEclogites
DS2003-1401
2003
Maruyama, S.Usui, T., Nakamura, E., Kobayashi, K., Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate inferred from eclogite xenoliths in the ColoradoGeology, Vol. 31, 7, July, pp. 589-592.Colorado Plateau, New Mexico, WyomingSubduction
DS200412-0878
2004
Maruyama, S.Isjikawa, A., Maruyama, S., Komiya, T.Layered lithospheric mantle beneath the Ontong Java Plateau: implications from xenoliths in alnoite, Malaita, Solomon Islands.Journal of Petrology, Vol. 45, 10, pp. 2011-2044.Indonesia, Solomon IslandsPeridotite, pyroxenites, xenoliths, geothermometry
DS200412-0961
2003
Maruyama, S.Katayama, I., Muko, A., Izuka, T., Maruyama, S., Terada, K., Tsutsumi, Y., Sany, Y., Zhang, R.Y., Liou, J.G.Dating of zircon from Ti clinohumite bearing garnet peridotite: implication for timing of mantle metasomatism.Geology, Vol. 31, 8, pp. 713-716.MantleGeochronology
DS200412-1140
2004
Maruyama, S.Liou, J.G., Tsujimori, T., Zhang, R.Y., Katayama, I., Maruyama, S.Global UHP metamorphism and continental subduction collision: the Himalayan model.International Geology Review, Vol. 46, 1, pp. 1-27.EuropeUHP - subduction not specific to diamonds
DS200412-1235
2003
Maruyama, S.Maruyama, S.The western Pacific triangular zone: frontier to form a future supercontinent.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p. 428.Pacific IslandsSubduction - not specific to diamonds
DS200412-1236
2003
Maruyama, S.Maruyama, S.Significance of UHP mineralogy in collisional belt: insight from the Kokchetav Massif.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.227.Russia, KazakhstanUHP
DS200412-1237
2003
Maruyama, S.Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate referred from eclogite xenoliths in the Colorado Plateau.Geology, Vol. 31, 7, July pp. 589-92.United States, ColoradoCoesite, zircon, geochronology
DS200412-1238
2003
Maruyama, S.Maruyama, S., Parkinson, C.D., Liou, J.G.Overview of the tectonic evolution of the Kokchetav Massif and the role of fluid in subduction and exhumation.Frontiers Science Series, University Academy Press, Vol. 38, pp. 427-42.RussiaTectonics
DS200412-1240
2003
Maruyama, S.Masago, H., Rumble, D., Ernst, W.G., Parkinson, C.D., Maruyama, S.Low delta 8 O eclogites from the Kokchetav Massif, northern Kazakhstan.Journal of Metamorphic Geology, Vol. 21, 6, pp. 579-88.Russia, KazakhstanEclogite
DS200412-1458
2002
Maruyama, S.Ogasawara, Y., Ohta, M., Fukasawa, K., Katayama, I., Maruyama, S.Petrology of diamond bearing dolomite marble from Kumdy Kol.Frontiers Science Series, University Academy Press, Vol. 38, pp. 191-212.ChinaPetrology
DS200412-1805
2004
Maruyama, S.Shimizu, K., Nakamara, E., Kobayashi, K., Maruyama, S.Discovery of Archean continental and mantle fragments inferred from xenocrysts in komatiites, the Belingwe greenstone belt, ZimbGeology, Vol. 32, 4, pp. 285-288.Africa, ZimbabweXenocrysts
DS200412-2028
2003
Maruyama, S.Usui, T., Nakamura, E., Kobayashi, K., Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate inferred from eclogite xenoliths in the Colorado Plateau.Geology, Vol. 31, 7, July, pp. 589-592.United States, ColoradoSubduction
DS200412-2174
2003
Maruyama, S.Yang, Y.S., Wooden, J.L., Wu,C.L., Liu, F.L., Xu,ZQ, Shi, R.D., Katayama, I., Liou, J.G., Maruyama, S.SHRIMP U Pb dating of coesite bearing zircon from the ultrahigh pressure metamorphic rocks, Sulu terrane, east China.Journal of Metamorphic Geology, Vol. 21, 6, pp. 551-60.ChinaUHP
DS200512-0558
2005
Maruyama, S.Komabayahi, T., Omori, S., Maruyama, S.Experimental and theoretical study of stability of dense hydrous magnesium silicates in the deep upper mantle.Physics of the Earth and Planetary Interiors, Vol. 153, 4, Dec. 15, pp. 191-209.MantleUHP, peridotites, subduction, Geothermometry, water
DS200512-0690
2005
Maruyama, S.Maruyama, S., Liou, J.G.From snowball to Phanerozoic Earth.International Geology Review, Vol. 47, 7, pp. 775-791.MantleTectonics
DS200612-0599
2006
Maruyama, S.Horie, K., Komiya, T., Maruyama, S., Hirata, T., Hidaka, H., Windley, B.F.4.2 Ga zircon xenocryst in an Acasta gneiss from northwestern Canada: evidence for early continental crust.Geology, Vol.34, 4, April pp. 245-248.Canada, Northwest TerritoriesGeochronology, spectrometry
DS200612-1006
2006
Maruyama, S.Okamoto, K., Katayama, I., Maruyama, S., Liou, J.G.Zircon inclusion mineralogy of a diamond grade eclogite from the Kokchetav Massif, northern Kazakhstan.International Geology Review, Vol. 48, 10, Oct., pp. 882-891.RussiaEclogite mineralogy
DS200712-0691
2007
Maruyama, S.Maruyama, S., Santosh, M., Zhao, D.Superplume, supercontinent, and post perovskite: mantle dynamics and anti-plate tectonics on the core mantle boundary.Gondwana Research, Vol. 11, 1-2, Jan. pp. 7-37.MantlePlume
DS200812-0717
2008
Maruyama, S.Maruyama, S., Santosh, M.Models on snowball Earth and Cambrian explosion: a synopsis.Gondwana Research, Vol. 14, 1-2, August pp. 22-32.MantleSnowball
DS200812-0718
2008
Maruyama, S.Maruyama, S., Santosh, M.Snowball Earth to Cambrian explosion.Gondwana Research, Vol. 14, 1-2, August pp. 1-4.MantleSnowball
DS200912-0364
2009
Maruyama, S.Kawait, K., Tsuchiya, T., Tuchiyama, J., Maruyama, S.Lost primordial continents.Gondwana Research, Vol. 16, 3-4, pp. 581-586.MantleMagmatism
DS200912-0397
2009
Maruyama, S.Komabayashi, T., Maruyama, S., Rino, S.A speculation on the structure of the 'D' layer: the growth of anti-crust at the core mantle boundary through the subduction history of the Earth.Gondwana Research, Vol. 15, 3-4, pp. 342-353.MantleSubduction
DS200912-0475
2009
Maruyama, S.Maruyama, S., Hasegawa, A., Santosh, M., Kogiso, T., Omori, S., Nakamura, H., Kawai, K., Zhao, D.The dynamics of big mantle wedge, magma factory, and metamorphic-metasomatic factory in subduction zones.Gondwana Research, Vol. 16, 3-4, pp. 414-430.MantleSubduction
DS200912-0476
2009
Maruyama, S.Masago, H., Omori, S., Maruyama, S.Counter clockwise prograde P-T path in collisional orogeny and water subduction at the Precambrian Cambrian boundary: the ultrahigh pressure KochetavGondwana Research, Vol. 15, 2, pp. 137-150.RussiaUHP
DS200912-0663
2009
Maruyama, S.Santosh, M., Maruyama, S., Omori, S.A fluid factory in solid Earth.Lithosphere, Vol. 1, no. 1, pp. 29-33.MantleTectonics, plumes
DS201012-0659
2010
Maruyama, S.Santosh, M., Maruyama, S., Komiya, T., Yamamoto, S.Orogens in the evolving Earth: from surface continents to 'lost continents'.The evolving continents: understanding processes of continental growth, Geological Society of London, Vol. 338, pp. 77-106.MantleGeodynamics
DS201312-0432
2013
Maruyama, S.Izuka, T., Campbell, I.H., Allen, C.M., Gill, J.B., Maruyama, S., Makota, F.Evolution of the African continental crust as recorded by U-Pb, Lu-Hf and O isotopes in detrital zircons from modern rivers.Geochimica et Cosmochimica Acta, Vol. Pp. 96-120.AfricaGeochronology, Comgo, Zambesi, Orange
DS201312-0464
2013
Maruyama, S.Kawai, K., Yamamoto, S.,Tsuchiya, T., Maruyama, S.The second continent: existence of granitic continental materials around the bottom of the mantle transition zone.Geoscience Frontiers, Vol. 4, 1, pp. 1-6.MantleGranites
DS201312-0925
2013
Maruyama, S.Tsuchiya, T., Kawai, K., Maruyama, S.Expanding-contracting Earth.Geoscience Frontiers, Vol. 4, 3, pp. 341-347.MantleCore, dynamics
DS201412-0389
2014
Maruyama, S.Ichikawa, H., Kameyama, M., Senshu, H., Kawai, K., Maruyama, S.Influence of majorite on hot plumes.Geophysical Research Letters, Vol. 26, pp. 461-468.MantleHotspots
DS201412-0767
2014
Maruyama, S.Safonova, I., Maruyama, S., Litasov, K.Generation of hydrous plumes in the mantle transition zone linked to the tectonic erosion of continental crust.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 3p. AbstractMantleSubduction
DS201604-0619
2016
Maruyama, S.Maruyama, S.Plume, superplume, plate tectonics, and Earth system.Japan Geoscience Union Meeting, 1p. AbstractMantleGeodynamics
DS201612-2278
2016
Maruyama, S.Azuma, S., Yamamoto, S., Ichikawa, H., Maruyama, S.Why primordial continents were recycled to the deep: role of subduction erosion.Geoscience Frontiers, in press availableMantleSubduction

Abstract: Geological observations indicate that there are only a few rocks of Archean Earth and no Hadean rocks on the surface of the present-day Earth. From these facts, many scientists believe that the primordial continents never existed during Hadean Earth, and the continental volume has kept increasing. On the other hand, recent studies reported the importance of the primordial continents on the origin of life, implying their existence. In this paper, we discussed the possible process that could explain the loss of the primordial continents with the assumption that they existed in the Hadean. Although depending on the timing of the initiation of plate tectonics and its convection style, subduction erosion, which is observed on the present-day Earth, might have carried the primordial continents into the deep mantle.
DS201908-1811
2019
Maruyama, S.Santosh, M., Maruyama, S., Sawaki, Y., Meert, J.G.The Cambrian explosion: plume-driven birth of the second ecosystem on Earth. Gondwana Research, doi.org/10.1016 /j.gr.2013.03.013 21p. PdfAfrica, Mozambiquetectonics

Abstract: The birth of modern life on Earth can be linked to the adequate supply of nutrients into the oceans. In this paper, we evaluate the relative supply of nutrients into the ocean. These nutrients entered the ocean through myriad passageways, but primarily through accelerated erosion due to uplift. In the ‘second ecosystem’, uplift is associated with plume-generation during the breakup of the Rodinia supercontinent. Although the evidence is somewhat cryptic, it appears that the second ecosystem included the demospongia back into the Cryogenian (~ 750 Ma). During the Ediacaran-Cambrian interval, convergent margin magmatism, arc volcanism and the closure of ocean basins provided a second pulse of nutrient delivery into the marine environment. A major radiation of life forms begins around 580 Ma and is represented by the diverse and somewhat enigmatic Ediacaran fauna followed by the Cambrian Explosion of modern phyla during the 540-520 Ma interval. Tectonically, the Ediacaran-Cambrian time interval is dominated by the formation of ultra-high pressure (UHP), high pressure (HP) and ultra-high temperature (UHT) orogenic belts during Gondwana orogenesis. Erosion of this extensive mountainous region delivered vast nutrients into the ocean and enhanced the explosiveness of the Cambrian radiation. The timing of final collisional orogeny and construction of the mountain belts in many of the Gondwana-forming orogens, particularly some of those in the central and eastern belts, post-date the first appearance of modern life forms. We therefore postulate that a more effective nutrient supply for the Cambrian radiation was facilitated by plume-driven uplift of TTG crust, subsequent rifting, and subduction-related nutrient systems prior to the assembly of Gondwana. In the outlined scenario, we propose that the birth of the ‘second ecosystem’ on our planet is plume-driven.
DS200812-0961
2008
Maruyana, S.Rio, S., Kon, Y., Sato, W., Maruyana, S., Santosh, M., Zhao, D.The Grenvillian and Pan African orogens: world's largest orogenies through geologic time, and their implications on the origin of superplume.Gondwana Research, Vol. 14, 1-2, August pp. 51-72.MantleOrogeny
DS200912-0664
2009
Maruyana, S.Santosh, M., Maruyana, S., Yamamoto,S.The making and breaking od supercontinents: some speculations based on superplumes, super downwelling and the role of tectosphere.Gondwana Research, Vol. 15, 3-4, pp. 324-341.MantlePlume, hotspots
DS1986-0059
1986
Marvakov, D.I.Bashenov, V.K., Kardashev, D.L., Marvakov, D.I.Orbital removal method for the neutral vacancy in semiconductorsNational Technical Information Service DE 87701537/XAD July 86 (IC 86-197), 8pGlobalExperimental- demonstrated for diamond
DS202110-1609
2021
Marvillet, E.Dasari, V., Sharma, A., Marvillet, E., Singh, P., Rudashevsky, V., Alikin, O., Zaveri, V.Liberation of emeralds from micaeous host rocks using electric-pulse dissaggregation vs conventional processing.Journal of Gemmology, Vol. 37, 7, pp. 716-724.Globalemeralds

Abstract: In ore processing, electric-pulse disaggregation (EPD) is used for the liberation of mineral crystals from host rocks. Since 2019, EPD technology has been used exclusively to recover emeralds produced from the Kagem mine in Zambia. This article compares the differences in the recovery of emeralds from micaceous schist host rock at the Kagem mine by EPD technology versus the conventional hand-cobbing method. The amount of emeralds obtained using both methods was similar, but EPD had numerous advantages in terms of liberation speed, ease of performing the process and the characteristics of the liberated emeralds.
DS1960-0702
1966
Marvin, R.F.Lidiak, E.G., Marvin, R.F., Thomas, H.H., Bass, M.N.Geochronology of the Mid-continent Region, United States. Pt. 1. Scope, Methods and Principles.Journal of GEOPHYSICAL RESEARCH, Vol. 71, PP. 5427-5438.GlobalMid-continent
DS1960-0713
1966
Marvin, R.F.Muehlberger, W.R., Hedge, C.E., Denison, R.E., Marvin, R.F.Geochronology of the Midcontinent Region, United States. Pt. 3, Southern Area.Journal of GEOPHYSICAL RESEARCH, Vol. 71, PP. 5409-5426.GlobalMid-continent
DS1960-0986
1968
Marvin, R.F.Marvin, R.F.Transcontinental Geophysical Survey (35 and 39 Degrees N) Radiometric age Determinations of Rocks.United States Geological Survey (USGS) MAP, No. MI-537.GlobalMid-continent, 35 - 39 Degrees N, Geochronology
DS1984-0643
1984
Marvin, R.F.Seager, W.R., Shafiquillah, M., Hawley, J.W., Marvin, R.F.New Potassium-argon Dates from Basalts and the Evolution of the Southern Rio Grande Rift.Geological Society of America (GSA) Bulletin., Vol. 95, No. 1, PP. 87-99.United States, Texas, New MexicoMid Continent
DS1989-1641
1989
Marvin, R.F.Witkind, I.J., Marvin, R.F.Significance of new potassium argon ages from the Golden Ranch and MoroniFormations, Sanpete-Sevier Valley area, centralUtahGeological Society of America Bulletin, Vol. 101, No. 4, April pp. 534-548UtahGeochronology
DS1989-1642
1989
Marvin, R.F.Witkind, I.J., Marvin, R.F.Significance of new potassium-argon ages from the Goldens Ranch and MoroniFormations, Sanpete-Sevier Valley area, central UtahGeological Society of America (GSA) Bulletin, Vol. 101, No. 4, pp. 534-548UtahMinette
DS2002-0401
2002
Marwick, A.Downes, H., Marwick, A., Kempton, P.D., Thirwall, M.F.The lower crust beneath cratonic NE Europe isotopic constraints from garnet granulite xenoliths.Terra Nova, Vol. 13, No. 6, pp. 395-400.northeast EuropeGeochronology
DS2001-0735
2001
Marwick, A.J.Marwick, A.J., Downes, H., Verennikov, N.The lower crust of southeast Belarus: petrological, geophysical and geochemical constraints from xenoliths.Tectonophysics, Vol. 339, No. 1-2, pp. 215-37.RussiaPetrology, Xenoliths
DS1975-1127
1979
Marx, M.Marx, M.Western Australia: When the Rains Cease?Indiaqua., No. 20, 1979/1, PP. 17-22.AustraliaKimberlite, Diamond, Argyle
DS2003-0884
2003
Marx, M.Marx, M.Diamond bearing dykesRough Diamond Review, pp. 21-24. www.roughdiamondreview.com Aus $ 95.South AfricaDiamond genesis, comparison, Deposit - Messina, Star
DS200412-1239
2003
Marx, M.Marx, M.Diamond bearing dykes.Rough Diamond Review, pp. 21-24. Aus $ 95.Africa, South AfricaDiamond genesis, comparison Deposit - Messina, Star
DS202008-1419
2018
Marx, M.Marx, M.The Orapa discovery - one small step.Botswana Journal of Earth Sciences, Vol. 7, pp. 1-2. pdfAfrica, Botswanadeposit - Orapa

Abstract: I feel tremendously honoured and privileged to be invited to attend the 50thanniversary celebrations of the Orapa discovery. Thank you, Leon Daniels and Debswana. This will be a very emotional and exciting experience for me to return to Orapa after 50 years, where early in the morning of the 21st of April 1967 my team of twelve Motswana explorers and I stepped onto a low calcrete hill littered with kimberlitic indicator minerals. This was not entirely unexpected, as some months earlier Dr Gavin Lamont (the exploration manager) and Jim Gibson (the senior geologist) had detected such minerals during a road sampling survey into this isolated region south of the Makgadigadi Pans. However, what was unexpected was the enormous size of this kimberlite pipe that was destined to become the world-class Orapa diamond mine.
DS1989-1284
1989
Marx, M.R.Robey, J.V.A., Bristow, J.W., Marx, M.R., Joyce, J., Danchin, R.V.Alkaline ultrabasic dikes near Norseman, western AustraliaGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 382-391AustraliaGeochronology, Lamprophyre
DS1994-1793
1994
Marx, M.R.Towie, N.J., Bush, M.D., Manning, E.R., Marx, M.R., Ramsay, R.R.The Aries Diamondiferous kimberlite pipe central Kimberley Block, westernAustralia: exploration, setting and evaluation.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 319-328.AustraliaDiamond exploration, Deposit -Aries
DS1970-0956
1974
Marx, W.Marx, W., Stockdale prospecting ltd.Final Report E.p.l. 17, Port AugustaSouth Australian Mines Department Report, UNPUBL.Australia, South AustraliaKimberlite Sills, Prospecting, El Alamein
DS201605-0866
2016
Marx, W.Marx, W., Hooman, M.Block cave mining operations - venillation challenges and opportunities.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 143-152.TechnologyMining - applied
DS1970-0755
1973
Marx, W.T.Marx, W.T., Colchester, D.M., Stockdale prospecting ltd.El 17 Port Augusta Area South Australia Progress and Final Reports from October 1972 to April 1974.South Australia Geological Survey, No. E 2140, 29P.Australia, South Australia, Port Augusta, Egypt, CorraberraGeochemistry, Prospecting
DS1981-0287
1981
Marx, W.T.Marx, W.T., Freeport of australia inc., SWAN RESOURCES LTD.El 558- Orroroo Region, South Australia Relinquishment ReporSouth Australia Open File., No. E4519, 9P. UNPUBL.Australia, South AustraliaGeophysics, Geochemistry, Stream Sediment Sampling, Prospecting
DS1982-0406
1982
Marx, W.T.Marx, W.T., Elliott, S.J., Swan Resources Ltd., Freeport of Aus.El 689- Orroroo Region, South Australia Progress and Final Reports from 11/11/80 to August 1982.South Australia Open File., No. E3920, 27P. 8 MAPS UNPUBL.Australia, South AustraliaGeophysics, Geochemistry, Stream Sediment Sampling, Heavy Minerals
DS1996-0897
1996
Marx, W.T.Marx, W.T.Bow River diamond mine - a case study of reporting of diamond explorationresults, identified resources....AusIMM Conference held March 24-26, Perth, pp. 309-311.AustraliaEconomics, ore reserves, geostatistics, Deposit - Bow River
DS2003-0276
2003
Marx, W.T.Cooper, S.A., MacRae, C.M., Wilson, N.C., Scarlett, N.V.Y., Marx, W.T.Diamond coatings that affect diamond recoveries on grease tables investigated by8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractSouth AfricaKimberlite geology and economics, Technology - recovery, Perdevlei, Kareevlei
DS2000-0398
2000
MaryamaHayashi, M., Komya, Nakamura, MaryamaArchean regional metamorphism of the Isua greenstone belt: implications driving force for plate tectonicsInternational Geology Review, Vol.42, 12, Dec. pp. 1055-1115.Greenland, southwestTectonics
DS1998-0512
1998
MaryinezGillet, Ph., Matas, Fiquet, Chamorro, Maryinez, JambonVolatiles in the Earth's mantle: insights from mineral and melt physicsMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 521-2.MantleMagnesite, noble gases, volcanism.
DS1986-0221
1986
Marynick, D.S.Estle, T.L., Estreicher, S., Marynick, D.S.Preliminary calculations confirming that anomalous muonium in diamond and silicon is bond centered interstitial muoniuM.Hyperfine Interact, Vol. 32, No. 1-4, pp. 637-639GlobalCrystallography, Diamond
DS1986-0222
1986
Marynick, D.S.Estreicher, S., Marynick, D.S.Lattice relaxation for normal muonium in diamondHyperfine Interact, Vol. 32, No. 1-4, pp. 613-617GlobalCrystallography, Diamond
DS1986-0224
1986
Marynick, D.S.Estreicher, S., Ray, A.K., Fry, J.L., Marynick, D.S.Surface effects in cluster calculations of energy profiles of muonium indiamond. reply to commentsPhys. Rev. Letters, Vol. 57, No. 26, p. 3301GlobalCrystallography, Diamond
DS1990-1599
1990
Maryuama, S.Xiaomin Wang, Liou, J.G., Maryuama, S.Regional ultrahigh pressure metamorphic terrane in central ChinaEos, Vol. 71, No. 43, October 23, p. 1708 AbstractChinaEclogites, Metamorphic
DS2002-0871
2002
Maryyama, S.Komiya, T., Hayashi, M., Maryyama, S., Yurimoto, H.Intermediate P T type Archean metamorphism of the Isua supracrustal beltAmerican Journal of Science, Vol. 302, 9, pp. 806-26.GreenlandSubduction
DS1991-1745
1991
Marz, M.R.Towie, N.J., Marz, M.R., Bush, M.D., Manning, E.R.The Aries Diamondiferous kimberlite pipe: central Kimberley Block, westernAustraliaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 435-436AustraliaSampling, prospecting, geophysics, Structure, geochemistry, alluvials
DS201910-2283
2019
Marzen, R.E.Marzen, R.E., Shillington, D.E., Lizarralde, D., Harder, S.H.Constraints on Appalachian orogenesis and continental rifting in the southeastern United States from wide angle seismic data.Journal of Geophysical Research: Solid Earth, Vol. 174, 7, pp. 6625-6652.United Statesgeophysics - seismic

Abstract: The Southeastern United States is an ideal location to understand the interactions between mountain building, rifting, and magmatism. Line 2 of the Suwannee suture and Georgia Rift basin refraction seismic experiment in eastern Georgia extends 420 km from the Inner Piedmont to the Georgia coast. We model crustal and upper mantle VP and upper crustal VS. The most dramatic model transition occurs at the Higgins?Zietz magnetic boundary, north of which we observe higher upper crustal VP and VS and lower VP/VS. These observations support the interpretation of the Higgins?Zietz boundary as the Alleghanian suture. North of this boundary, we observe a low?velocity zone less than 2 km thick at ~5?km depth, consistent with a layer of sheared metasedimentary rocks that forms the Appalachian detachment. To the southeast, we interpret synrift sediments and decreasing crustal thickness to represent crustal thinning associated with the South Georgia Rift Basin and subsequent continental breakup. The correspondence of the northern limit of thinning with the interpreted suture location suggests that the orogenic suture zone and/or the Gondwanan crust to the south of the suture helped localize subsequent extension. Lower crustal VP and VP/VS preclude volumetrically significant mafic magmatic addition during rifting or associated with the Central Atlantic Magmatic Province. Structures formed during orogenesis and/or extension appear to influence seismicity in Georgia today; earthquakes localize along a steeply dipping zone that coincides with the northern edge of the South Georgia Basin and the change in upper crustal velocities at the Higgins?Zietz boundary.
DS1993-0977
1993
Marzocchi, W.Marzocchi, W., Mulargia, F.Patterns of hot spot volcanismJournal of Geophysical Research, Vol. 98, No. B8, August 10, pp. 14, 029-14, 040.GlobalGeophysics -pattern recognition, seismic, Tectonics
DS200712-0061
2007
Marzola, M.Beccaluva, L., Azzouni Sekkal, A., Benhallou, A., Bianchini, G., Ellam, R.M., Marzola, M., Siena, StuartIntracratonic asthenosphere upwelling and lithosphere rejuvenation beneath the Hoggar swell (Algeria): evidence from HIMU metasomatized lherzolite mantle.Earth and Planetary Science Letters, Vol. 260, 3-4, pp. 482-494.Africa, AlgeriaMetasomatism
DS2000-0780
2000
MarzoliPrincivalle, F., Salviulo, G., Marzoli, PiccirilloClinopyroxene of spinel peridotite mantle xenoliths from Lake Nji: crystal chemistry and petrological....Contributions to Mineralogy and Petrology, Vol. 139, No. 5, pp. 503-8.GlobalMantle xenoliths
DS1998-0952
1998
Marzoli, A.Marzoli, A., Renne, P.R., et al.The earliest Jurassic circum Atlantic large igneous province: new evidence for a brief extremely widespreadMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 961-2.BrazilMagmatism, Geochronology
DS201112-0134
2011
Marzoli, A.Callegaro, S., Marzoli, A., Bertrand, H., Reisberg, L., Chiaradia, M., Beelieni, G.Geochemistry of eastern North American CAMP diabase dykes.Goldschmidt Conference 2011, abstract p.614.United States, AppalachiaCentral Atlantic Province .... basaltic
DS201112-0616
2011
Marzoli, A.Longo, M., Nimis, P., Ziberna, L., Marzoli, A., Zanetti, A., Franz, L.Geochemistry of xenoliths from the Gibeon kimberlite province, Namibia.Goldschmidt Conference 2011, abstract p.1354.Africa, NamibiaOff-craton
DS201112-0649
2011
Marzoli, A.Marzoli, A., Aka, F.T., Chiaradia, M., Reisberg, L., Merle, R.Origin of Cameroon Line basanites from metasomatized lithosphere.Goldschmidt Conference 2011, abstract p.1420.Africa, CameroonCongo craton keel
DS201112-0732
2011
Marzoli, A.Nestola, F., Nimis, P., Ziberna, L., Longo, M., Marzoli, A., Harris, J.W., Manghnani, M.H., Fedortchuk, Y.First crystal structure determination of olivine in diamond: composition and implications for provenance in the Earth's mantle.Earth and Planetary Science Letters, Vol. 305, 1-2, pp. 249-255.MantleInclusion - olivine in diamond
DS201112-1173
2011
Marzoli, A.Ziberna, L., Nimis, P., Zanetti, A., Sobolev, N.V., Marzoli, A.Geochemistry of mantle microxenoliths from Zagadochnaya kimberlite, Yakutia, Russia.Goldschmidt Conference 2011, abstract p.2283.Russia, YakutiaNarren Type II kimberlite
DS201312-1022
2013
Marzoli, A.Ziberna, L., Nimis, P., Zanetti, A., Marzoli, A., Sobolev, N.V.Metasomatic processes in the central Siberian cratonic mantle: evidence from garnet xenocrysts from the Zagadochnaya kimberlite.Journal of Petrology, Vol. 54, pp. 2379-2409.Russia, SiberiaDeposit - Zagadochnaya
DS202107-1122
2021
Marzoli, A.Ozkan, M., Faruk, O., Marzoli, A., Cortuk, R.M., Billor, M.Z.The origin of carbonatites from the eastern Armutlu Peninsula, ( NW Turkey).Journal of the Geological Society , https://doi.org/10.1144/jgs2020-171Europe, Turkeycarbonatite

Abstract: Unusual carbonate dykes, which have a thickness of up to 4 m, cross-cut the amphibolites from the high-grade metamorphic rocks in the Armutlu Peninsula (NW Turkey). They are described as carbonatites on the basis of their petrographic, geochemical and isotope-geochemical characteristics. The carbonatites, which commonly show equigranular texture, are composed of calcite and clinopyroxene with other minor phases of plagioclase, mica, garnet, K-feldspar, quartz, epidote, titanite and opaque minerals. They contain abundant xenoliths of pyroxenite and amphibolite. The geochemical characteristics of the carbonatites are significantly different from those of mantle-derived carbonatites. They have remarkably low incompatible element (e.g. Ba, Th, Nb) and total REE (11-91 ppm) contents compared with mantle-derived carbonatites. The high 87Sr/86Sr(i) (0.70797-0.70924) and low ?Nd(t) (?8.08 to ?9.57) of the carbonatites confirm that they were derived from the continental crust rather than from a mantle source. Mica from carbonatite was dated by the 40Ar/39Ar method, yielding a Late Jurassic-Early Cretaceous age (148-137 Ma). This is significantly younger than the age of adjacent amphibolites (Upper Triassic). All data from field studies, as well as petrographic, geochemical and geochronological observations, suggest that these carbonatites were formed from anatectic melting of a carbonated source area in the continental crust.
DS202112-1941
2021
Marzoli, A.Ozkan, M., Celik, O.F., Marzoli, A., Cortuk, R.M., Billor, M.Z.The origins of carbonatites from the eastern Armutlu Peninsula, ( NW Turkey).Journal of the Geological Society, Vol. 178, 10.1144/jgs2020-171Asia, Turkeydeposit - Armutlu

Abstract: Unusual carbonate dykes, which have a thickness of up to 4 m, cross-cut the amphibolites from the high-grade metamorphic rocks in the Armutlu Peninsula (NW Turkey). They are described as carbonatites on the basis of their petrographic, geochemical and isotope-geochemical characteristics. The carbonatites, which commonly show equigranular texture, are composed of calcite and clinopyroxene with other minor phases of plagioclase, mica, garnet, K-feldspar, quartz, epidote, titanite and opaque minerals. They contain abundant xenoliths of pyroxenite and amphibolite. The geochemical characteristics of the carbonatites are significantly different from those of mantle-derived carbonatites. They have remarkably low incompatible element (e.g. Ba, Th, Nb) and total REE (11-91 ppm) contents compared with mantle-derived carbonatites. The high 87Sr/86Sr(i) (0.70797-0.70924) and low ?Nd(t) (?8.08 to ?9.57) of the carbonatites confirm that they were derived from the continental crust rather than from a mantle source. Mica from carbonatite was dated by the 40Ar/39Ar method, yielding a Late Jurassic-Early Cretaceous age (148-137 Ma). This is significantly younger than the age of adjacent amphibolites (Upper Triassic). All data from field studies, as well as petrographic, geochemical and geochronological observations, suggest that these carbonatites were formed from anatectic melting of a carbonated source area in the continental crust.
DS202204-0516
2022
Marzoli, A.Boscaini, A., Marzoli, A., Bertrand, H., Chiagradia, M., Jourdan, F., Faccende, M., Meyzen, C.M., Callegaro, S., Duran, L. Cratonic keels controlled the emplacement of the Central Atlantic Magmatic Province ( CAMP)Earth and Planetary Science Letters, Vol. 584, doi 10.1016/j.espl.2022.117480Africa, Mali, Mauritaniacraton

Abstract: Large Igneous Provinces (LIPs) are exceptionally voluminous magmatic events frequently related to continental break-up, global climate changes and mass extinctions. One interesting aspect of many LIPs is their spatial proximity to cratons, begging the question of a potential control of thick lithosphere on their emplacement. In this study, we investigate the relationship between the emplacement of the Central Atlantic Magmatic Province (CAMP) and the thick lithospheric mantle of the Precambrian cratons that formed the central portion of Pangea and are currently located on the continents surrounding the Central Atlantic Ocean. CAMP outcrops are frequently located over the margins of the thick cratonic keels, as imaged by recent tomographic studies, suggesting a role of lithosphere architecture in controlling magma genesis and emplacement. Here we focus on CAMP dykes and sills from the Hank, Hodh, and Kaarta basins in North-Western Africa (NW-Africa, Mali and Mauritania) emplaced at the edge of the Reguibat and Leo-Man Shields. The investigated intrusive rocks show compositions similar to most CAMP magmas, in particular those of the Tiourjdal geochemical group, limited to NW-Africa, and of the Prevalent group, occurring all over the CAMP. Geochemical modelling of CAMP basalts requires a Depleted MORB Mantle (DMM) source enriched by recycled continental crust (1-4%) and melting beneath a lithosphere of ca. 80 km in thickness. On the contrary, melting under a significantly thicker lithosphere (>110 km) does not produce magmas with compositions similar to those of CAMP basalts. This suggests that CAMP magmatism was likely favoured by decompression-induced partial melting of the upwelling asthenospheric mantle along the steep lithospheric boundaries of stable cratons. The architecture of the pre-existing lithosphere (i.e., the presence of stable thick cratonic keels juxtaposed to relatively thinner lithosphere) appears to have been a critical factor for localizing mantle upwelling and partial melting during extensive magmatic events such as in the CAMP.
DS2002-0957
2002
MasagoLiu, F., Xu, Z., Liu, J.G., Katayama, Masago, Maruyama, YangUltra high pressure mineral inclusions in zircons from gneissic core samples of the Chinese continental drilling site in eastern China.European Journal of Mineralogy, No. 3, pp. 499-512.China, easternUHP, Mineral inclusions
DS2003-0885
2003
Masago, H.Masago, H., Rumble, D., Ernst, W.G., Parkinson, C.D., Maruyama, S.Low delta 8 O eclogites from the Kokchetav Massif, northern KazakhstanJournal of Metamorphic Geology, Vol. 21, 6, pp. 579-88.Russia, KazakhstanEclogites
DS200412-1240
2003
Masago, H.Masago, H., Rumble, D., Ernst, W.G., Parkinson, C.D., Maruyama, S.Low delta 8 O eclogites from the Kokchetav Massif, northern Kazakhstan.Journal of Metamorphic Geology, Vol. 21, 6, pp. 579-88.Russia, KazakhstanEclogite
DS200912-0476
2009
Masago, H.Masago, H., Omori, S., Maruyama, S.Counter clockwise prograde P-T path in collisional orogeny and water subduction at the Precambrian Cambrian boundary: the ultrahigh pressure KochetavGondwana Research, Vol. 15, 2, pp. 137-150.RussiaUHP
DS1999-0393
1999
MasaitisLangenhorst, F., Shafranovsky, Masaitis, KoivistoDiscovery of impact diamonds in a Fennoscandian crater and evidence #NAME? solid state transformation.Geology, Vol. 27, No. 8, Aug. pp. 747-50.Finland, Baltic StatesDiamond genesis, Lappajarvi Crater
DS1995-1174
1995
Masaitis, V.Masaitis, V.Diamond bearing impactites and problems of their developmentMineral Resources of Russia, abstract, pp. 37-44.RussiaAstroblemes, Popigai impact region
DS201412-0823
2014
Masaitis, V.Shumilova, T., Kis, K.V., Masaitis, V., Isaenko, S., Makeev, B.Onion-like carbon in impact diamonds from the Popigai astrobleme.European Journal of Mineralogy, Vol. 26, 2, pp. 267-277.RussiaLonsdaleite, raman spectroscopy
DS201608-1416
2016
Masaitis, V.Kis, V.K., Shumilova, T., Masaitis, V.HRTEM study of Popigai impact diamond: heterogeneous diamond nanostructures in native amorphous carbon matrix.Physics and Chemistry of Minerals, in press available 10p.TechnologyImpact diamond

Abstract: High-resolution transmission electron microscopy was applied for the detailed nanostructural investigation of Popigai impact diamonds with the aim of revealing the nature of the amorphous carbon of the matrix. The successful application of two complementary specimen preparation methods, focused ion beam (FIB) milling and mechanical cleavage, allowed direct imaging of nanotwinned nanodiamond crystals embedded in a native amorphous carbon matrix for the first time. Based on its stability under the electron beam, native amorphous carbon can be easily distinguished from the amorphous carbon layer produced by FIB milling during specimen preparation. Electron energy loss spectroscopy of the native amorphous carbon revealed the dominance of sp2-bonded carbon and the presence of a small amount of oxygen. The heterogeneous size distribution and twin density of the nanodiamond crystals and the structural properties of the native amorphous carbon are presumably related to non-graphitic (organic) carbon precursor material.
DS201611-2122
2016
Masaitis, V.Kis, V.K., Shumilova, T., Masaitis, V.HRTEM study of Popigai impact diamond: heterogeneous diamond nanostructures in native amorphous carbon matrix.Physics and Chemistry of Minerals, Vol. 43, 9, pp. 661-670.RussiaImpact diamonds

Abstract: High-resolution transmission electron microscopy was applied for the detailed nanostructural investigation of Popigai impact diamonds with the aim of revealing the nature of the amorphous carbon of the matrix. The successful application of two complementary specimen preparation methods, focused ion beam (FIB) milling and mechanical cleavage, allowed direct imaging of nanotwinned nanodiamond crystals embedded in a native amorphous carbon matrix for the first time. Based on its stability under the electron beam, native amorphous carbon can be easily distinguished from the amorphous carbon layer produced by FIB milling during specimen preparation. Electron energy loss spectroscopy of the native amorphous carbon revealed the dominance of sp2-bonded carbon and the presence of a small amount of oxygen. The heterogeneous size distribution and twin density of the nanodiamond crystals and the structural properties of the native amorphous carbon are presumably related to non-graphitic (organic) carbon precursor material.
DS1994-0661
1994
Masaitis, V.L.Grieve, R.A.F., Masaitis, V.L.The economic potential of terrestrial impact cratersInternational Geology Review, Vol. 36, No. 2, February pp. 105-151.GlobalDistribution -impact craters, Review
DS1994-0662
1994
Masaitis, V.L.Grieve, R.A.F., Masaitis, V.L.The economic potential of terrestrial impact cratersInternational Geology Review, Vol. 36, No. 2, February pp. 105-151GlobalImpact craters
DS1994-1121
1994
Masaitis, V.L.Masaitis, V.L.Diamondiferous impactites, their distribution and petrogenesis. (Russian)Regional Geology and Metallogeny (Russian), No. 1, p. 121RussiaImpact crater
DS1996-0566
1996
Masaitis, V.L.Grieve, R.A.F., Masaitis, V.L.Impact diamondsGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 183-186.CanadaImpact structure, Carbonados
DS1997-0610
1997
Masaitis, V.L.Koeberl, C., Masaitis, V.L., Shafranovsky, GilmourDiamonds from the Popigal impact structure, RussiaGeology, Vol. 25, No. 11, Nov. pp. 967-970.Russia, SiberiaMineralogy impact diamonds, Sample techniques
DS201412-0222
2003
Masaitis, V.L.El Goresy, A., Dubrovinsky, L.S., Gillet, P., Mostefaoui, S., Graup, G., Drakopoulos, M., Simionovici, A.S., Swamy, V., Masaitis, V.L.A new natural, super-hard, transparent polymorph of carbon from the Popigai impact crater, Russia.Comptes Rendus Geoscience, Vol. 335, pp. 889-898.Russia, YakutiaMeteorite
DS201412-0558
2013
Masaitis, V.L.Masaitis, V.L.Impact diamonds of the Popigai astrobleme: main properties and practical use.Geology of Ore Deposits, Vol. 55, 8, pp. 607-612.Russia, SiberiaAstrobleme
DS201902-0326
2019
Masake, E.Taguchi,T., Igami, Y., Miyake, A., Masake, E.Factors affecting preservation of coesite in ultrahigh-pressure metamorphic rocks: insights from TEM observations of dislocations within kyanite Sulu China.Journal of Metamorphic Geology, https://doi.org/10.1111/jmg.12470Chinacoesite

Abstract: To understand the preservation of coesite inclusions in ultrahigh?pressure (UHP) metamorphic rocks, an integrated petrological, Raman spectroscopic and focused ion beam (FIB) system-transmission electron microscope (TEM) study was performed on a UHP kyanite eclogite from the Sulu belt in eastern China. Coesite grains have been observed only as rare inclusions in kyanite from the outer segment of garnet and in the matrix. Raman mapping analysis shows that a coesite inclusion in kyanite from the garnet rim records an anisotropic residual stress and retains a maximum residual pressure of approximately 0.35 GPa. TEM observations show quartz is absent from the coesite inclusion-host kyanite grain boundaries. Numerous dislocations and sub?grain boundaries are present in the kyanite, but dislocations are not confirmed in the coesite. In particular, dislocations concentrate in the kyanite adjacent to the boundary with the coesite inclusion, and they form a dislocation concentration zone with a dislocation density of ~109 cm?2. A high?resolution TEM image and a fast Fourier transform?filtered image reveal that a tiny dislocation in the dislocation concentration zone is composed of multiple edge dislocations. The estimated dislocation density in most of the kyanite away from the coesite inclusion-host kyanite grain boundaries is ~108 cm?2, being lower than that in kyanite adjacent to the coesite. In the case of a coesite inclusion in a matrix kyanite, using Raman and TEM analyses we could not identify any quartz at the grain boundaries. Dislocations are not observed in the coesite, but numerous dislocations and stacking faults are developed in the kyanite. The estimated overall dislocation density in the coesite?bearing matrix kyanite is ~108 cm?2, but a high dislocation density region of ~109 cm?2 is also present near the coesite inclusion-host kyanite grain boundaries. Inclusion and matrix kyanite grains with no coesite have dislocation densities of ?108 cm?2. Dislocation density is generally reduced during an annealing process, but our results show that not all dislocations in the kyanite have recovered uniformly during exhumation of the UHP rocks. Hence, one of the key factors acting as a buffer to inhibit the coesite to quartz transformation is the mechanical interaction between the host and the inclusion that lead to the formation of dislocations in the kyanite. The kyanite acts an excellent pressure container that can preserve coesite during the decompression of rocks from UHP conditions. The search for and study of inclusions in kyanite may be a more suitable approach for tracing the spatial distribution of UHP metamorphic rocks.
DS1993-0978
1993
Masaki EnamiMasaki Enami, Quija Zang, Yujun Yinhigh pressure eclogites in northern Jiangsu -southern Shandong Province, eastern China.Journal of Metamorphic Geology, Vol. 11, pp. 589-603.ChinaEclogites, metamorphism
DS1970-0346
1971
Masaytis, V.L.Masaytis, V.L., Mikhaylov, M.V., Plotnikova, M.I., et al.Age of the Kimberlite Pipe Mir and Remarks on a Paper by Mikheyenko and Neneshev.Geologii i Geofiziki, No. 11, PP. 150-154.RussiaBlank
DS1989-0952
1989
Masaytis, V.L.Masaytis, V.L.The economic geology of impact cratersInternational Geology Review, Vol. 31, No. 9, September pp. 922-933RussiaImpact craters
DS1991-1539
1991
Masaytis, V.L.Selivanovskaya, T.V., Mashchak, M.S., Masaytis, V.L.Impact breccias and impactites of the Kara and Ust-Kara astroblemesInternational Geology Review, Vol. 33, No. 5, May pp. 448-477RussiaImpact crater, Kara
DS1989-1593
1989
Mascall, G.Wellesley-Wood, M., Mascall, G., Williams, HuwLondon: the capital source. International mining financeInternational Mining, Vol. 6, No. 3, March pp. 34, 36, 38-39GlobalEconomics, Mine financing
DS1982-0631
1982
Mascarenas, J.F.Wenrich, K.J., Mascarenas, J.F.Map Showing Uranium Bearing Diatremes of the Hopi Buttes Arizona.United States Geological Survey (USGS) miscellaneous FIELD STUDIES MAP, MF-1310, 1: 50, 000.GlobalDiatreme
DS1982-0632
1982
Mascarenas, J.F.Wenrich, K.J., Mascarenas, J.F.Diatremes of the Hopi Buttes, Arizona: Chemical and Statistical Analyses.United States Geological Survey (USGS) OPEN FILE REPORT., No. 82-740, 126P.GlobalDiatreme
DS2000-0196
2000
MascarenhasCunha, J.C., Mascarenhas, Silva, Garrido, SampaioIntegrated airborne geophysical and geological studies of the Mundo Novo greenstone belt, Bahia, Brasil.Igc 30th. Brasil, Aug. abstract only 1p.Brazil, BahiaCraton - Sao Francisco, Mobile belt
DS1998-0953
1998
Mascle, A.Mascle, A., et al.Cenozoic foreland basins of western EuropeGeological Society of London Spec. Pub, No. 134, 400p. $ 117.00EuropeBook - ad, Basins
DS1993-1837
1993
Mascle, G.Zubieta-Rosseti, D., Huyghe, P., Mascle, G., Mugnier, J-L, Baby, P.Influence de l'heritage ante-devonien au front de la chaine andine (Partiecentrale de la Bolivie).(in French)Comptes Rendus Academy Science Paris, (in French), Tomb. 316, Series II, pp. 951-957BoliviaGeophysics -seismics, Structure
DS1997-0060
1997
Mascle, G.Baby, P., Rochat, P., Mascle, G., Herail, G.Neogene shortening contribution to crustal thickening in the back arc Of the Central AndesGeology, Vol. 25, No. 10, Oct., pp. 883-886Bolivia, AndesThrust systems, Tectonics, geophysics
DS1986-0531
1986
Mascle, J.Mascle, J., Marinho, M., Wannesson, J.The structure of the Guinean continental margin: Implications for the connection between the central and south AtlanticoceansGeologische Rundschau, Vol. 75, No. 1, pp. 57-70GuineaTectonics
DS1987-0442
1987
Mascle, J.Mascle, J., Blarez, E.Evidence for transform margin evolution from the Ivory Coast Ghanacontinental marginNature, Vol.326, No. 6111, March 26, pp. 378-380GhanaWest Africa, Craton
DS1988-0443
1988
Mascle, J.Mascle, J., Blarez, E., Marinho, M.The shallow structures of the Guinea and Ivory Coast-Ghana transformmargins: their bearing on the equatorial Atlantic Mesozoic evolutionTectonophysics, Vol. 155, No. 1-4, Dec. 1, pp. 193-210GhanaStructure
DS1991-0220
1991
Mascle, J.Caprona, G.C., Mascle, J.The western Ivory coast margin: result of intra-continental shearingC.r. Acad. Paris, Vol. 312, II, pp; 1565-71.GlobalStructure, Margin - coast
DS1991-0360
1991
Mascle, J.Decaprona, G.C., Mascle, J.The Western Ivory Coast margin - result of an intra-continentalshearing.(in French)Comptes Rendus de l'Academie des Sciences Series II, (in French), Vol. 312, No. 13, June 20, pp. 1565-1572GlobalStructure, Tectonics
DS1995-0141
1995
Mascle, J.Benkhelil, J., Mascle, J.The Guinea continental margin: an example of a structurally complex transform marginTectonophysics, Vol. 248, No. 1-2, Aug. 15, pp. 117-138GuineaTectonics, Structure
DS2000-0625
2000
Mascle, J.Mascle, J., Benkhelil, J., Bellaiche, Zitter, WoodsideMarine geologic evidence for a Levantine Sinai plate: a new piece of evidence of the Mediterranean puzzle.Geology, Vol. 28, No. 9, Sept. pp. 779-82.Africa, North AfricaTectonics
DS201807-1517
2018
Masemola, S.Musenwa, L., Khumalo, T., Kgaphola, M., Masemola, S., van Wyk, G.The new Culli nan AG milling circuit - a narrative of progress. MiningSAIMM Diamonds - source to use 2018 Conference 'thriving in changing times'. June 11-13., pp. 45-64.Africa, South Africadeposit - Cullinan
DS202008-1425
2019
Masemola, S.Musenwa, L., Khumalo, T., Kgaphola, M., Masemola, S., van Wyk, G.The new Cullinan AG milling circuit - a narrative of progress.The Journal of the Southern African Insitute of Mining and Metallurgy, Vol. 119, Feb. 10p. PdfAfrica, South Africadeposit - Cullinan

Abstract: In 2017, Petra Diamonds completed the construction and commissioning of a modern, fit-for-purpose diamond processing plant at Cullinan Diamond Mine (CDM). The design of CDM's milling circuit is unconventional in that it comprises an autogenous (AG) mill with a grate discharge with large ports, low-revolution jaw crushers, and high-pressure grinding roll crushers with large operating gaps. In this paper we review the design to provide guidance on what is expected from the milling circuit and to demonstrate how the design aims to address challenges experienced in the old plant, which was based on staged crushing technology. We assessed the performance of the CDM AG milling circuit from commissioning and early production stages to examine its impact along multiple dimensions. In the assessment we sought to understand the lessons from our milling circuit regarding diamond liberation, energy consumption, and the future of diamond processing as a whole.
DS1991-1069
1991
Mashchak, M.S.Mashchak, M.S.Geologic setting in Kara and Ust-Kara at time of formation of the impactcraterInternational Geology Review, Vol. 33, No. 5, May pp. 423-432RussiaImpact crater, Kara
DS1991-1539
1991
Mashchak, M.S.Selivanovskaya, T.V., Mashchak, M.S., Masaytis, V.L.Impact breccias and impactites of the Kara and Ust-Kara astroblemesInternational Geology Review, Vol. 33, No. 5, May pp. 448-477RussiaImpact crater, Kara
DS1992-0964
1992
Mashchakov, A.M.Lukyanova, L.I., Maruechevm A.M., Mashchakov, A.M., et al.The first findings of the Lamproite magmatism manifestations on the southUrals.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 324, No. 6, pp. 1187-1190.RussiaLamproite
DS201605-0867
2016
Mashino, I.Mashino, I., Murakami, M., Ohtani, E.Sound vehicles of AlOOH up to core mantle boundary pressures with implications for the seismic anomalies in the deep mantle.Journal of Geophysical Research,, Vol. 121, 2, pp. 595-609.MantleBoundary
DS201212-0197
2012
Mashkovtsev, R.Fedorova, E.N., Logvinova, A.M., Mashkovtsev, R., Sobolev, N.V.Internal structure and color of the natural plastically deformed diamonds from the Internationalnaya kimberlite pipe, Yakutia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Internationnaya
DS1994-1122
1994
Mashukov, V.I.Mashukov, V.I., Pirlya, K.V., Kramskov, N.P.Substaniation of a geomechanical concept for working out the kimberlite deposits of south Yakutia.Russian Journal of Mining Science, *ENG, Vol. 30, No. 4, pp. 355-361.Russia, YakutiaMining, Deposit -Mir
DS201012-0081
2009
MasielloBurns, R.C., Chumakov, A.I., Connell, Dube, Godfried, Hansen, Hartwig, Hoszowska, Masiello, Mkonza, RebakHPHT growth and x-ray characterization of the high quality type IIa diamond.Journal of Physics Condensed Matter, Vol. 21, 36, pp. 364224-364237.TechnologyType II a
DS1982-0407
1982
Masire, Q.K.J.Masire, Q.K.J.As Rare as Rain in the Kgalagadi... Botswana's ThirdIndiaqua., No. 33, PP. 11-17.BotswanaMining Methods, Production
DS1987-0094
1987
Maske, S.Cawthorn, R.G., Maske, S., de Wit, M., Groves, D.I., Cassidy, K.Mineralogical geochemical indicators of the formation conditions of apatite bearing carbonatites of the Arbarastakh Massif,Southern Yakutia (USSR).(Russian)Canadian Mineralogist, In pressSouth AfricaGenesis, Magma
DS1988-0134
1988
Maske, S.Clendenin, C.W., Charlesworth, E.G., Maske, S.Tectonic style and mechanism of early Proterozoic successor basindevelopment, southern AfricaTectonophysics, Vol. 156, No. 3-4, December 20, pp. 275-292South AfricaTectonics, Basin
DS1859-0118
1855
Maskelyne, N.S.Maskelyne, N.S.On the History of the Koh-i-noor DiamondAshmolean Soc. Proceedings (oxford), Vol. 3, PP. 59-63.IndiaDiamonds Notable
DS1860-0003
1860
Maskelyne, N.S.Maskelyne, N.S.On Diamonds. the History of the Koh-i-noorRoy. Institute Proceedings, Vol. 3, PP. 229-233. ALSO: CHEM. NEWS Vol. 1, PP. 208-213. AIndiaDiamonds Notable
DS1860-0235
1874
Maskelyne, N.S.Maskelyne, N.S., Flight, W.On the Character of the Diamondiferous Rock of South AfricaQuarterly Journal of Geological Society (London), Vol. 30, PP. 406-416.Africa, South Africa, Cape ProvinceMineralogy
DS1860-0342
1880
Maskelyne, N.S.Maskelyne, N.S.The Asserted Artificial Production of the DiamondNature., Vol. 21, PP. 203-204.GlobalSynthetic
DS1860-0387
1882
Maskelyne, N.S.Maskelyne, N.S.Enstatite Rock from South AfricaCrystallogr. Soc. Proceedings, PP. 60-62.Africa, South Africa, Cape Province, TransvaalPetrology
DS1860-0416
1883
Maskelyne, N.S.Maskelyne, N.S.Artficial DiamondsNature., Vol. 21, P. 260. ALSO: SOC. ARTS Journal of, Vol. 28, P. 289.GlobalSynthetic
DS1860-0417
1883
Maskelyne, N.S.Maskelyne, N.S.The Supposed Artificial Production of the DiamondChem. News, Vol. 41, PP. 4-5.GlobalSynthetic
DS201811-2569
2018
Maslakov, K.I.Ekimov, E.A., Sidorov, V.A., Maslakov, K.I., Sirotinkin, B.P., Krotova, M.D., Pleskov, Yu.V.Influence of growth medium composition on the incorporation of boron in HPHT diamond.Diamond & Related Materials, Vol. 89, pp. 101-107.Mantleboron

Abstract: Influence of growth medium composition on the efficiency of boron doping of carbonado-like diamond at 8-9 GPa was studied by diluting the C-B growth system with metallic solvents of carbon, Co and Ni. Addition of these metals to the original system leads to a decrease in the synthesis temperature, degree of doping with boron and suppression of superconductivity in diamond. According to XPS analysis, content of substitutional boron is equal to 0.07, 0.16 and 0.39 at.% in diamonds obtained in Co-C-B, Ni-C-B and C-B growth systems, respectively. Metallic behavior at normal temperatures and superconductivity below 5 K in diamond, synthesized in C-B system, change to semiconducting character of conductivity down to 2 K in diamonds obtained in the diluted systems; a faint hint of superconducting transition at 2 K was detected in the case of diamond grown in Ni-C-B system. By comparing phase composition of the inclusions and the doping efficiency of the diamonds, we are able to suggest that high chemical affinity of boron to boride-forming metals hinders the boron doping of diamond. The heavily boron-doped carbonado-like diamond compacts demonstrate high electrochemical activity in aqueous solutions and can be used as miniature electrodes in electrosynthesis and electroanalysis.
DS201812-2805
2018
Maslakov, K.I.Ekimov, E.A., Sidorov, V.A., Maslakov, K.I., Sirotinkin, B.P., Krotova, M.D., Pleskov, Yu.V.Influence of growth medium composition on the incorporation of boron in HPHT diamond.Diamond & Related Materials, Vol. 89, pp. 101-107.Mantlecarbonado
DS1992-0947
1992
Maslanyj, M.P.Light, M.P.R., Maslanyj, M.P., Banks, N.L.New geophysical evidence for extensional tectonics on the divergent margin offshore NamibiaGeological Society Special Publication, Magmatism and the Causes of Continental, No. 68, pp. 257-270NamibiaTectonics, Geophysics -offshore
DS2002-1003
2002
Maslennikova, Y.V.Maslennikova, Y.V., Kolume, F.N., Possoukhova, T.V., Novgorodova, M.L.Diamonds and accompanying minerals from the Sierra Leone placers18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.148.Sierra LeoneDiamond - morphology, alluvials
DS2002-1004
2002
Maslov, A.V.Maslov, A.V., Isherskaya, M.V.Riphean sedimentary sequences of the eastern and northeastern margins of the Eastern European Craton.Russian Journal of Earth Science, Vol. 4, 4, AugustEurope, Asia, RussiaCraton
DS1996-0898
1996
Maslov, V.K.Maslov, V.K.Role of fluid (mud) volcanism in the formation of early Jurassic deposits and commercial minerals in Yakutia.Russian Geology and Geophysics, Vol. 36, No. 7, pp. 39-49.Russia, YakutiaAldan shield - all mineralization brief mention diamond
DS1985-0359
1985
Maslovska.Kostrovitsky, S.I., Dneprovskaya, L.V., Brandt, S.S., Maslovska.Correlation of Strontium, Carbon and Oxygen Isotope Distributions in Carbonates from Kimberlite Pipes of Yakutia.Doklady Academy of Science USSR, Earth Science Section., Vol. 272, No. 1-6, MARCH PP. 205-208.RussiaGeochemistry
DS200612-0366
2006
MaslovskayaEgorov, K.N., Soloveva, Kovach, Menshagin, Maslovskaya, Sekerin, BankovskayaPetrological features of olivine phlogopite lamproites of the Sayan region: evidence from the Sr Nd isotope and ICP MS trace element data.Geochemistry International, Vol. 44, 7. pp. 729-735.RussiaLamproite
DS200612-0367
2005
MaslovskayaEgorov, K.N., Soloveva, L.V., Kovach, V.P., Menshagin, Y.V., Maslovskaya, Sekerin, A.P., Bankovskaya, E.V.Mineralogical and isotope geochemical characteristics of Diamondiferous lamproites of the Sayan region.Doklady Earth Sciences, Vol. 403A, 6, pp. 861-865.RussiaGeochronology
DS200712-0876
2007
MaslovskayaRasskazov, S.V., Ilyasova, A.M., Konev, A.A., Yasnygina, Maslovskaya, Feflov, Demonterova, SaraninaGeochemical evidence of the Zadoi alkaline ultramafic Massif, Cis Sayan area southern Siberia.Geochemistry International, Vol. 45, 1, pp. 1-14.Russia, SiberiaAlkalic
DS1984-0491
1984
Maslovskaya, M.N.Maslovskaya, M.N., Yegorov, K.N., Kolosnitsyna, T.I., Brandt, S.Strontium Isotope Distribution Rubidium Strontium Age and Rare Alkalies of Micas from Yakutian Kimberlites.Doklady Academy of Science USSR, Earth Science Section., Vol. 266, No. 1-6, MAY PP. 149-152.RussiaGeochronology, Mir, Udachnaya
DS1991-1808
1991
Maslovskaya, M.N.Vladimirov, B.M., Egorov, K.N., Maslovskaya, M.N., DneprovskayaBasaltic and mica kimberlites of the Siberian platform and their time space and genetic relationshipsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 573-575RussiaGeochronology, Deposit -Udachnya
DS1983-0370
1983
Maslovskaya.Kostrovitskiy, S.I., Dneprovskaya, L.V., Brandt, S.S., Maslovskaya.Correlations Between Isotopic Compositions of Strontium, Carbon, AndDoklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 272, No. 5, pp. 1223-1225RussiaGeochronology, Strontium, Lead, Carbonate
DS1998-0667
1998
MaslovskyaIvanov, A.V., Rasskazov, Boven, Andre, Maslovskya, TemuLate Cenozoic alkaline ultrabasic and alkaline basanite magmatism of the Rung we Province, TanzaniaPetrology, Vol. 6, No. 3, June, pp. 208-229.RussiaAlkaline rocks, Brief overview
DS1991-1070
1991
Maslowski, A.Maslowski, A.Glacial erraticsRock and GeM., Vol. 21, No. 3, March pp. 76-79United StatesGeomorphology, Popular account -mentions diamonds
DS200612-1010
2006
Maslowski, A.Olson, R., Eccles, D.R., Pana, D., Edwards, D., Beaton,A., Maslowski, A.Summary of mineral exploration during 2005, Diamondiferous kimberlites ( 2p.)Alberta Geological Survey, Jan. 20, 2p.Canada, AlbertaNews item - exploration activity
DS1975-1128
1979
Maslowski, A.J.Maslowski, A.J.Glacial DiamondsGems And Minerals, JANUARY, P. 50; PP. 72-73.United States, Great Lakes, WisconsinGeomorphology, Diamond Occurrence
DS1986-0532
1986
Maslowski, A.J.Maslowski, A.J.Glacial diamonds: America's oldest jewelry importAmerican Jewelry Manufacture, Vol. 34, No. 4, pp. 54-56GlobalUSA, History
DS2003-0886
2003
Maslyaev, G.A.Maslyaev, G.A.Pulsating endogenic activation of the Russian platform lithosphere at its plateDoklady Earth Sciences, Vol. 391A, 6, July-August, pp. 775-78.RussiaTectonics
DS200412-1241
2003
Maslyaev, G.A.Maslyaev, G.A.Pulsating endogenic activation of the Russian platform lithosphere at its plate development stage.Doklady Earth Sciences, Vol. 391A, 6, July-August, pp. 775-78.RussiaTectonics
DS200912-0721
2009
MasonSpengler, D., Brueckner, H.K., Herman, L.M., Van Roermund, Drury, MasonLong lived, cold burial of Baltica to 200 km depth.Earth and Planetary Science Letters, Vol. 281, 1-2, April 30, pp. 27-35.Europe, Baltic ShieldSubduction
DS202106-0956
2021
MasonMason, E, Wieser, P.E., Liu, E.J., Edmonds, M., Ilyinskaya, E., Whitty, R.C., Mather, T.A., Elias, T., Nadeau, P.A., Wilkes, T.C., McGonigle, A.J.S., Pering, T.D., Mims, F.M., Kern, C., Schneider, D.J., Oppenheimer, C.Volatile metal emissions from volcanic gassing and lava-seawater interactions at Kilauea volcano, Hawaii.Earth & Environment Communications, 10.1038/s43247-021-00145-3 16p. PdfUnited States, Hawaiimagmatism

Abstract: Volcanoes represent one of the largest natural sources of metals to the Earth’s surface. Emissions of these metals can have important impacts on the biosphere as pollutants or nutrients. Here we use ground- and drone-based direct measurements to compare the gas and particulate chemistry of the magmatic and lava-seawater interaction (laze) plumes from the 2018 eruption of K?lauea, Hawai’i. We find that the magmatic plume contains abundant volatile metals and metalloids whereas the laze plume is further enriched in copper and seawater components, like chlorine, with volatile metals also elevated above seawater concentrations. Speciation modelling of magmatic gas mixtures highlights the importance of the S2? ligand in highly volatile metal/metalloid degassing at the magmatic vent. In contrast, volatile metal enrichments in the laze plume can be explained by affinity for chloride complexation during late-stage degassing of distal lavas, which is potentially facilitated by the HCl gas formed as seawater boils.
DS1960-0706
1966
Mason, B.Mason, B.Pyrope, Augite and Hornblende from Kakanui, New ZealandNew Zealand Journal of Geology Geophys., Vol. 9, PP. 474-480. PP. 175-179.AustraliaKimberlite, Non Kimberlitic Breccia Pipes
DS1992-1009
1992
Mason, B.Mason, B.Victor Moritz Goldschmidt, Father of modern geochemistryGeochemical Society, Special Pub. No. 4, 210p. approx. $ 40.00GlobalBook -ad, Geochemistry biography of Goldschmidt
DS1997-0367
1997
Mason, B.Gaines, R.V., Skinner, H.C., Foord, E.E., Mason, B.Dana's new mineralogy. Eigth editionJ. Wiley, approx. $ 300.00 United StatesGlobalBook - ad, Mineralogy
DS201808-1748
2018
Mason, B.S.Greaves, J.S., Scaife, A.M.M., Frayer, D.T., Green, D.A., Mason, B.S., Smith, A.M.S.Anomalous microwave emission from spinning nanodiamonds around stars.Nature Astronomy, doi.org/10.1038/s41550-018-0495-zGlobalnanodiamonds

Abstract: Several interstellar environments produce 'anomalous microwave emission', with brightness-peaks at tens-of-gigahertz frequencies. The emission's origins are uncertain - rapidly-spinning nano-particles could emit electric-dipole radiation, but polycyclic aromatic hydrocarbons proposed as the carrier are now found not to correlate with Galactic signals. The difficulty is to identify co-spatial sources over long lines of sight. Here we identify anomalous microwave emission in three proto-planetary discs. These are the only known systems that host hydrogenated nano-diamonds, in contrast to very common detection of polycyclic aromatic hydrocarbons. Spectroscopy locates the nano-diamonds close to the host-stars, at physically-constrained temperatures. Developing disc models, we reproduce the emission with diamonds 0.75-1.1 nanometres in radius, holding less than or equal to 1-2 per cent of the carbon budget. The microwave-emission:stellar-luminosity ratios are approximately constant, allowing nano-diamonds to be ubiquitous but emitting below detection thresholds in many star-systems. This can unify the findings with similar-sized diamonds found within solar system meteorites. As nano-diamond spectral absorption is seen in interstellar sightlines, these particles are also a candidate for generating galaxy-scale anomalous microwave emission.
DS1992-1615
1992
Mason, D.C.Wadge, G., Young, A.V., Mason, D.C.Simulation of geological processes using an expert systemJournal of Geology Society of London, Vol. 149, No. 3, May pp. 455-464GlobalComputers, Expert system
DS1975-1129
1979
Mason, D.O.Mason, D.O., Mayer, T.E. , Cra exploration pty. ltd.Progress and Final Reports on Kangaroo Island, El 319, South Australia.South Australia Open File., No. E3051, 39P. UNPUBL.Australia, South AustraliaGeochemistry, Prospecting, Stream Sediment Sampling, Soil, Rock
DS200512-1193
2005
Mason, I.M.Wolmarans, A., Cloete, J.H., Ekkerd, J., Mason, I.M., Simmat, C.M.Borehole radar application to kimberlite delineation at Finsch diamond mine.Exploration Geophysics, Vol. 36, 3, pp. 310-317.Africa, South AfricaFinsch mine
DS1991-1071
1991
Mason, J.Mason, J.The invisible obstacle race... for women in scienceNature, Vol. 353, Sept. 19, pp. 205-206GlobalWomen in science, Progress?
DS1997-0741
1997
Mason, J.D.Mason, J.D., Rachmalla, K.S.Exploration financing - innovative approach lowers risk17th. World Mining Congress Oct. Mexico, pp. 459-470CanadaEconomics, discoveries, Risk Financing
DS201112-0650
1997
Mason, K.Mason, K.Crater facies kimberlites. Yubileinya depositThesis, 'BSc. Lakehead University, Russia, YakutiaThesis - note availability based on request to author
DS1982-0227
1982
Mason, M.G.Gregory, G.P., Mason, M.G., Pedler, A.D., Williams, S.D.Argyle Diamond Deposit Western AustraliaConfidential Report In-house., JULY 6TH. 5P.Australia, Western AustraliaGeology, Petrology, Mineralogy
DS2000-0679
2000
Mason, P.J.Moore, J.McM., Mason, P.J., et al.Applied tectonic geomorphology for diamond prospecting in the Tarim Basin Xinjiang: using combined digital ...14th. International Conference Applied Remote Sensing, Nov. pp. 289-96.ChinaRemote sensing - hyperspectral imagery, Kalakash, Yuungkash River catchments
DS200712-0059
2007
Mason, P.R.Beard, A.D., Downes, H., Mason, P.R., Vetrin, V.R.Depletion and enrichment processes in the lithospheric mantle beneath the Kola Peninsula ( Russia): evidence from spinel lherzolite and wehrlite xenoliths.Lithos, Vol. 94, 1-4, pp. 1-24.RussiaXenoliths
DS1996-0899
1996
Mason, P.R.D.Mason, P.R.D., Downes, H., Mattey, D.Crustal assimilation as a major petrogenetic process in the East Carpathian Neogene and Quat. margin arcJournal of Petrology, Vol. 37, No. 4, Aug. 1, pp. 927-960RomaniaTectonics
DS1998-0094
1998
Mason, P.R.D.Beard, A.D., Mason, P.R.D., Downes, H.Depletion and enrichment processes in lithospheric mantle beneath the Baltic Shield (Kola and Arkangelsk)7th International Kimberlite Conference Abstract, pp. 58-60.Russia, Kola Peninsula, ArkangelskSpinel, garnet peridotites, Xenoliths
DS1998-0954
1998
Mason, P.R.D.Mason, P.R.D., Downes, H., Jarvis, K., Vannucci, R.An investigation of incompatible trace elements in Massif Central mantle xenoliths by laser ablation.7th International Kimberlite Conference Abstract, pp. 549-1MantleGeochemistry - ICP-MS, Xenoliths -light rare earth element (LREE).
DS2003-0349
2003
Mason, P.R.D.Downes, H., Reichow, M.K., Mason, P.R.D., Beard, A.D., Thirlwall, M.F.Mantle domains in the lithosphere beneath the French Massif Central: trace element andChemical Geology, Vol. 200, 1-2, Oct. 16, pp. 71-87.Europe, FranceGeochronology, Peridotites
DS200412-0477
2004
Mason, P.R.D.Downes, H., Macdonald, R., Upton, B.G.J., Cox, K.G., Bodinier, J-L., Mason, P.R.D., James, D., Hill, P.G., HeaUltramafic xenoliths from the Bearpaw Mountains, Montana: USA: evidence for multiple metasomatic events in the lithospheric mantJournal of Petrology, Vol. 45, 8, pp. 1631-1662.United States, MontanaMetasomatism
DS200412-0479
2003
Mason, P.R.D.Downes, H., Reichow, M.K., Mason, P.R.D., Beard, A.D., Thirlwall, M.F.Mantle domains in the lithosphere beneath the French Massif Central: trace element and isotopic evidence from mantle clinopyroxeChemical Geology, Vol. 200, 1-2, Oct. 16, pp. 71-87.Europe, FranceGeochronology, peridotites
DS200612-0103
2006
Mason, P.R.D.Beard, A.D., Downes, H., Mason, P.R.D., Vetrin, V.R.Depletion and enrichment processes in the lithospheric mantle beneath the Kola Peninsula (Russia): evidence from spinel lherzolite wehrlite xenoliths.Lithos, in pressRussia, Kola PeninsulaMetasomatism, Kandalaksha
DS200912-0299
2009
Mason, P.R.D.Hin, R.C., Morel, M.L.A., Nebel, O., Mason, P.R.D., Van Westeren, W., Davies, G.R.Formation and temporal evolution of the Kalahari sub-cratonic lithospheric mantle: constraints from Venetia xenoliths, South Africa.Lithos, In press - available 30p.Africa, South AfricaDeposit - Venetia
DS200912-0402
2009
Mason, P.R.D.Koorneef, J.M., Davies, G.R., Dopp, S.P., Vukmanovic, Z., Nikogosian, I.K., Mason, P.R.D.Nature and timing of multiple metasomatic events in the sub-cratonic lithosphere beneath Labait, Tanzania.Lithos, In press availableAfrica, TanzaniaMetasomatism
DS201902-0303
2018
Mason, P.R.D.Nikogosian, I.K., Bracco Gartner, A.J.J., Bergen, M.J., Mason, P.R.D., Hinsbergen, D.J.J.Mantle sources of recent Anatolian intraplate magmatism: a regional plume or local tectonic origin?Tectonics, Vol. 37, 12, pp. 4535-4566.Asia, Turkeymagmatism

Abstract: We present an extensive study of rehomogenized olivine?hosted melt inclusions, olivine phenocrysts, and chromian spinel inclusions to explore the link between geodynamic conditions and the origin and composition of Pliocene-Quaternary intraplate magmatism in Anatolia at Kula, Ceyhan?Osmaniye, and Karacada?. Exceptional compositional variability of these products reveals early and incomplete mixing of distinct parental melts in each volcanic center, reflecting asthenospheric and lithospheric mantle sources. The studied primitive magmas consist of (1) two variably enriched ocean island basalt (OIB)?type melts in Kula; (2) both OIB?type and plume mid?ocean ridge basalt (P?MORB)?like melts beneath Toprakkale and Üçtepeler (Ceyhan?Osmaniye); and (3) two variably enriched OIB?type melts beneath Karacada?. Estimated conditions of primary melt generation are 23-9 kbar, 75-30 km, and 1415-1215 °C for Kula; 28-19 kbar, 90-65 km, and 1430-1350 °C for Toprakkale; 23-18 kbar, 75-60 km, and 1400-1355 °C for Üçtepeler; and 35-27 kbar, 115-90 km, and 1530-1455 °C for Karacada?, the deepest levels of which correspond to the depth of the lithosphere?asthenosphere boundary in all regions. Although magma ascent was likely facilitated by local deformation structures, recent Anatolian intraplate magmatism seems to be triggered by large?scale mantle flow that also affects the wider Arabian and North African regions. We infer that these volcanics form part of a much wider Arabian?North African intraplate volcanic province, which was able to invade the Anatolian upper plate through slab gaps.
DS201904-0753
2019
Mason, P.R.D.Kroonenberg, S., Mason, P.R.D., Kriegsman, L. de Roever, E.W.F., Wong, T.E.Geology and mineral deposits of the Guiana Shield.SAXI-XI Inter Guiana Geological Conferene 2019: Paramaribo, Suriname, 6p. PdfSouth America, Brazil, VenezuelaGuiana shield

Abstract: The Guiana Shield records a long history that starts in the Archean, but culminates in the Trans-Amazonian Orogeny between 2.26-2.09 Ga as a result of an Amazonian-West-Africa collision. This event is responsible for the emplacement of a major part of its mineralisations, especially gold, iron and manganese. The diamondiferous Roraima Supergroup represents its molasse. Between 1.86 and 1.72 Ga the Rio Negro Block accreted in the west. The Grenvillian Orogeny caused shearing and mineral resetting between 1.3 and 1.1 Ga when Amazonia collided with Laurentia. Younger platform covers contain placer gold mineralisation. Several suits of dolerite dykes record short-lived periods of crustal extension. Bauxite plateaus cover various rock units.
DS201904-0760
2019
Mason, P.R.D.Naipal, R., Kroonenberg, S., Mason, P.R.D.Ultramafic rocks of the Paleoproterozoic greenstone belt in the Guiana shield of Suriname, and their mineral potential.SAXI-XI Inter Guiana Geological Conferene 2019: Paramaribo, Suriname, 5p. PdfSouth America, SurinameGuiana shield

Abstract: The ultramafic rocks of the Marowijne Greenstone Belt in Suriname and elsewhere in the Guiana Shield comprise both intrusive dunite-gabbroic bodies and ultramafic lavas and volcaniclastic rocks. They were emplaced in the early stages of the Trans-Amazonian Orogeny (2.26-2.09 Ga), but their petrogenesis and geotectonic significance have still to be elaborated. They present several economically interesting mineralisations, including chromium, nickel, platinum, gold and diamonds. In Suriname diamonds are found since the 19 th century; possible source rocks show similarities with the diamondiferous komatiitic volcaniclastic rocks in Dachine, French Guiana and in Akwatia in the Birimian Greenstone Belt of Ghana. This might point to a regionally extensive diamond belt in the Guiana Shield and its predrift counterpart in the West-African Craton.
DS202009-1644
2019
Mason, P.R.D.Naipal, R., Kroonenberg, S.B., Mason, P.R.D.Ultramafic rocks of the Paleoproterozoic greenstone belt in the Guiana shield of Suriname, and their mineral potential.SAXI-XI Inter Guiana Geological Conference, held Paramaribo, Suriname., 5p. PdfSouth America, Surinamediamond

Abstract: The ultramafic rocks of the Marowijne Greenstone Belt in Suriname and elsewhere in the Guiana Shield comprise both intrusive dunite-gabbroic bodies and ultramafic lavas and volcaniclastic rocks. They were emplaced in the early stages of the Trans-Amazonian Orogeny (2.26-2.09 Ga), but their petrogenesis and geotectonic significance have still to be elaborated. They present several economically interesting mineralisations, including chromium, nickel, platinum, gold and diamonds. In Suriname diamonds are found since the 19 th century; possible source rocks show similarities with the diamondiferous komatiitic volcaniclastic rocks in Dachine, French Guiana and in Akwatia in the Birimian Greenstone Belt of Ghana. This might point to a regionally extensive diamond belt in the Guiana Shield and its predrift counterpart in the West-African Craton.
DS202009-1645
2020
Mason, P.R.D.Naipal, R., Zwaan, J.C.(Hanco),, Kroonenberg, S.B., Kreigsman, L.M., Mason, P.R.D.Diamonds from the Nassau Mountains, Suriname.Journal of Gemmology, Vol. 37, 2, pp. 180-191. pdfSouth America, Surinamedeposit - Paramaka Creek

Abstract: Alluvial diamonds have been found in Suriname since the late 19th century, but to date the details of their origin remain unclear. Here we describe diamonds from Paramaka Creek (Nassau Mountains area) in the Marowijne greenstone belt, Guiana Shield, north-eastern Suriname. Thirteen samples were studied, consisting mainly of euhedral crystals with dominant octahedral and dodecahe-dral habits. They had colourless to brown to slightly greenish body colours, and some showed green or (less commonly) brown irradiation spots. Surface features showed evidence of late-stage resorption that occurred during their transport to the earth’s surface. The studied diamonds were predominantly type IaAB, with nitrogen as both A and B aggregates. In the DiamondView most samples displayed blue and/or green luminescence and concentric growth patterns. Their mineral inclusion assemblages (forsterite and enstatite) indicate a peridotitic (possibly harzburgitic) paragenesis.
DS1960-0934
1968
Mason, R.Crocket, R.N., Mason, R.Foci of Mantle Disturbance in Southern Africa and Their Economic Significance.Economic Geology, Vol. 63, PP. 532-540.South AfricaTectonics
DS1970-0756
1973
Mason, R.Mason, R.The Limpopo Mobile Belt, Southern AfricaRoyal Society of London PHIL. Transactions, Vol. 1273, PP. 463-485.South Africa, Botswana, LesothoRegional Geology, Tectonics
DS1970-0757
1973
Mason, R.Mason, R.The Limpopo Mobile Belt - Southern AfricaRoyal Society. Lond. Phil., Vol. A273, pp. 463-85.South AfricaKaapvaal Craton, Mobile Belt, Tectonics
DS1991-1072
1991
Mason, R.Mason, R.Basement tectonics 7thProceedings of the Seventh International Conference on basement, 500pIran, Africa, Kenya, Tanzania, Canada, South America, MoroccoBook -table of contents, Craton, structure, Rifts
DS1992-1661
1992
Mason, R.Whiting, B.H., Mason, R., Hodgson, C.J.Giant ore deposits #1Department of Geological Sciences, Queen's University, 550pGlobalDiamond, nickel, copper, platinum, Porphyry copper, molybdenum, sulphide
DS1993-1725
1993
Mason, R.Whiting, B., Hodgson, C.J., Mason, R.Giant Ore Deposits #2Society of Economic Geology Special Publication, No. 2, 404pGlobalBook -table of contents, Deposits -diamonds, nickel, gold, copper, moly, MVS
DS1998-0955
1998
Mason, R.Mason, R.Early Precambrian metallogeny - tops and bottoms of ore systems in ancient magmatic arcsPros. Developers Assoc, Short course pp. 103-114GlobalMagmatism, Metallogeny
DS2000-0107
2000
Mason, R.Brett, J.S., Mason, R., Smith, P.H.Geophysical exploration of the Kalahari Suture ZoneJournal of African Earth Sciences, Vol. 30, No.3, pp. 489-97.BotswanaTectonics, Geophysics
DS2003-0887
2003
Mason, T.Mason, T.Selection of plant for diamond ore concentrationRough Diamond Review, September, pp. 33-38Globaldiamond concentration & recovery plants - selection criteria, considerations
DS1997-0493
1997
Mason, T.R.Haycock, C.A., Mason, T.R., Watkeys, M.K.Early Triassic paleoenvironments in the eastern Karoo Foreland Basin, SouthAfrica.Journal of African Earth Sciences, Vol. 24, No. 1-2, Jan. pp. 79-94.South AfricaSedimentology, Karoo Basin
DS201212-0067
2012
Mason, W.Betts, G., Moresi, L.P.G., Mason, W.The influence of a mantle plume head on the dynamics of a retreating subduction zone.Geology, Vol. 40, 8, pp. 739-742.MantleSubduction, hotspots
DS200412-0754
2003
Mason-JoneGurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., Grutter, H.S., Coetzee, M., Mason-JoneKimberlite almanac.8 IKC Program, Session 8, POSTER abstractAfrica, South AfricaDiamond exploration Deposit - Finsch
DS2000-0698
2000
Masonne, H.J.Nasdala, L., Masonne, H.J.Microdiamonds from the Saxonian Erzgebirge, Germany: in situ micro-Raman characterization.European Journal of Mineralogy, Vol. 12, pp. 495-8.GermanyMicro diamonds, Metamorphism - ultra high pressure (UHP)
DS1960-0575
1965
Mason-Smith, D.Mason-Smith, D.Geophysical Surveys in Southern Bechuana land ProtectorateOverseas Geological Survey Min. Resour., REPORT No. 36.BotswanaGeophysics, Kimberlite, Diamond Prospecting
DS1960-0070
1960
Mason-Smith, D.J.Mason-Smith, D.J.Gravity Traverses over Kimberlite Pipes in TanganyikaOverseas Geological Survey Report, (UNPUBL.)Tanzania, East AfricaKimberlite, Geophysics
DS201312-0583
2013
Masotta, M.Masotta, M., Mollo, S., Freda, C., Gaeta, M., Moore, G.Clinopyroxene liquid thermometers and barometers specific to alkaline differentiated magmas.Contributions to Mineralogy and Petrology, Vol. 166, 6, pp. 1545-1561.Europe, ItalyCurrent volcanic eruptions
DS201012-0652
2010
Masquelin, H.Sanchez Bellucci, L., Peel, E., Masquelin, H.Neoproterozoic tectonic synthesis of Uruguay.International Geology Review, Vol. 52, 1, pp. 51-78.South America, UruguayTectonics
DS201012-0654
2010
Masquelin, H.Sanchez Bettucci, L., Peel, E., Masquelin, H.Neoproterozoic tectonic synthesis of Uruguay.International Geology Review, Vol. 52, 1, pp. 51-78.South America, UruguayTectonics
DS201112-0711
2011
Masquelin, H.Muzio, R., Scaglia, F., Masquelin, H.Petrochemistry of Mesozoic intrusions related to the Parana magmatic province, Uruguay.International Geology Review, In press available,South America, UruguayDike swarms
DS202004-0507
2020
Masquelin, H.Demarco, P.N., Masquelin, H., Prezzi, C., Muzio, R., Loureiro, J., Peel, E., Campal, N., Sanchez Bettucci, L. Aeromagnetic patterns in southern Uruguay: Precambrian- Mesozoic dyke swarms and Mesozoic rifting structural and tectonic evolution.Tectonophysics, in press available 40p. PdfSouth America, Uruguaygeophysics

Abstract: New high-resolution airborne magnetic data of Uruguay allowed constructing new maps concerning the spatial distribution of dyke swarms, main faults and other magnetic bodies, which compose the Uruguayan Shield. We combined geophysical analyses (vertical derivatives, upward continuation, Euler deconvolution), structural analyses of the magnetic maps and previous geological data in order to discriminate the main structural features of the Uruguayan Shield and contribute to a better understanding of its tectonic evolution. The magnetic maps revealed several outstanding features in the Uruguayan Shield. The Paleoproterozoic dyke swarm is larger, denser, more widespread and complex than originally thought, suggesting a possible plume origin. In addition, a new Mesozoic dyke swarm, as complex as the previous one, was identified crosscutting the Paleoproterozoic dyke swarm and the Neoproterozoic orogenic structures. Moreover, this swarm is connected to volcanic calderas in the Merín basin, and shows displacements along Neoproterozoic shear zones, in the magnetic maps, revealing its brittle reactivation during Mesozoic times. The new observations clarify how Proterozoic basement structures controlled the development of the Mesozoic rift. Paleoproterozoic dyke swarms were reactivated as normal faults and Neoproterozoic structures hindered the rift growth, deflecting the deformation in transcurrent movements. Meanwhile, the Mesozoic dyke swarm was developed in a perpendicular direction to the Neoproterozoic structures. Moreover, these findings contradict the current rift model for Uruguay and rise a new model in which the Mesozoic rift developed as two rift basins connected by a central transfer zone, generated by the reactivation of Dom Feliciano Belt structures, between the Sierra Ballena and Sarandí del Yí Shear Zones.
DS200912-0352
2009
Mass, R.Kamenetsky, V.S., Mass, R., Kamenetsky, M.B., Paton, C., Phillips, D., Golovin, A.V., Gornova, M.A.Chlorine from the mantle: magmatic halides in the Udachnaya-East kimberlite, Siberia.Earth and Planetary Science Letters, Vol. 285, pp. 96-104.Russia, SiberiaDeposit - Udachnaya
DS201112-0495
2011
Mass, R.Kamenetsky, V.S., Mass, R., Kamenetsky, M.B., Paton, C., Phillips, D., Golovin, A.V.Chlorine from the mantle: magmatic halides in the Udachnaya East kimberlite, Siberia.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 132-149.Russia, SiberiaModel magma compositions
DS2000-1036
2000
Massa, W.Yakubovich, O.V., Massa, W., Liferovich, PakhomovskyThe crystal structure of bakhchisaraitsevite: hydrothermal origin from Kovdor phoscorite carbonatiteCanadian Mineralogist, Vol. 38, 4, Aug. pp. 831-8.RussiaCarbonatite, Deposit - Kovdor
DS1998-1522
1998
Massare, D.Varela, M.E., Clochhiatti, R., Massare, D., Schiano, P.Metasomatism in subcontinental mantle beneath Northern Pategonia: evidence from silica rich melt inclusionsMin. Petrol, Vol. 62, No. 1-2, pp. 103-122ArgentinaMetasomatism, Magmatism
DS2002-1005
2002
Massare, D.Massare, D., Metrich, N., Clocchiatti, R.High temperature experiments on silicate melt inclusions in olivine at 1 atm: inference- temperatureChemical Geology, Vol.183, 1-4, pp.87-98.MantleMelt, Homogenization and H2O concentrations, water
DS201602-0195
2016
Massaro, F.R.Bruno, M., Rubbo, M., Aquilano, D., Massaro, F.R., Nestola, F.Diamond and olivine inclusions: a strange relation revealed by ab initio simulations.Earth and Planetary Science Letters, Vol. 435, 1, pp. 31-35.RussiaDeposit - Udachnaya

Abstract: The study of diamond and its solid inclusions is of paramount importance to acquire direct information on the deepest regions of the Earth. However, although diamond is one of the most studied materials in geology, the diamond-inclusion relationships are not yet understood: do they form simultaneously (syngenesis) or are inclusions pre-existing objects on which diamond nucleated (protogenesis)? Here we report, for the first time, adhesion energies between diamond (D) and forsterite (Fo) to provide a crucial contribution to the syngenesis/protogenesis debate. The following interfaces were investigated at quantum-mechanical level: (i) (001)D/(001)Fo, (ii) (001)D/(021)Fo, and (iii) (111)D/(001)Fo. Our data, along with the ones recently obtained on the (110)D/(101)Fo interface, revealed an unexpected thermodynamic behaviour, all interfaces showing almost equal and low adhesion energies: accordingly, diamond and olivine have an extremely low chemical affinity and cannot develop preferential orientations, even during an eventual epitaxial growth. Combining these results with those of our previous work concerning the morphology constraints of diamond on its inclusions, we can state that the two main arguments used so far in favour of diamond/inclusions syngenesis cannot be longer considered valid, at least for olivine.
DS201602-0223
2015
Masse, P.Masse, P., Laurent, O.Geological exploration of Angola from Sumbe to Namibe: a review at the frontier between geology, natural resources and the history of geology.Comptes Rendus Geoscience, in press available 9p.Africa, AngolaCoast - Angola

Abstract: This paper provides a review of the Geological exploration of the Angola Coast (from Sumbe to Namibe) from pioneer's first geological descriptions and mining inventory to the most recent publications supported by the oil industry. We focus our attention on the following periods: 1875-1890 (Paul Choffat's work, mainly), 1910-1949 (first maps at country scale), 1949-1974 (detailed mapping of the Kwanza-Namibe coastal series), 1975-2000, with the editing of the last version of the Angola geological map at 1:1 million scale and the progressive completion of previous works. Since 2000, there is a renewal in geological fieldwork publications on the area mainly due to the work of university teams. This review paper thus stands at the frontier between geology, natural resources and the history of geology. It shows how geological knowledge has progressed in time, fueled by economic and scientific reasons.
DS200712-0129
2006
Masselink, G.Buscombe, D., Masselink, G.Concepts in gravel beach dynamics.Earth Science Reviews, Vol. 79, 1-2, Nov. pp. 32-52.TechnologyBeach - sorting not specific to diamonds
DS201504-0207
2014
Masselot, M.J.Masselot, M.J.Diamants noirs polycrusallns rencontres en joaillerie.Thesis, 'Diplome D'Universite de Gemmologie devant l'Universite de Nantes U.F.R. des Sciemces et des Techniques, April , 55p. AvailableTechnologyBlack diamond
DS200512-0691
2005
Massi, L.Massi, L., Fritsch, E., Collins, A.T., Hainschwang, T., Notari, F.The amber centres and their relation to the brown colour in diamond.Diamond and Related Materials, Vol. 14, 10, pp. 1623-1629.TechnologyDiamond color
DS200612-0415
2006
Massi, L.Fristch, E., Massi, L., Hainschwang, T., Collins, A.T.The first color center related to the brown graining in type 1a natural diamonds.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p.TechnologyDiamond H- colour
DS200612-0521
2006
Massi, L.Hainschwang, T., Notari, F., Fritsch, E., Massi, L., Breeding, C.M., Rondeau, B.Natural CO2 rich colored diamonds.GIA Gemological Research Conference abstract volume, Held August 26-27, p. 33. 1/2p.TechnologySpectroscopy
DS200612-0872
2006
Massi, L.Massi, L.Chameleon diamonds: a proposed model to explain thermochromic and photochromic behaviors.GIA Gemological Research Conference abstract volume, Held August 26-27, p. 32-33. 1/2p.TechnologySpectroscopy
DS200712-0331
2007
Massi, L.Fritsch, E., Massi, L., Rossman, G.R., Hainschwang, T., Joba, S., Dessapt, R.Thermochromic and photochromic behaviour of chameleon diamonds.Diamond and Related Materials, Vol. 16, 2, pp. 401-408 Ingenta 1070685097TechnologyDiamond morphology
DS201312-0293
2013
MassinqueGao, S.S., Liu, Reed, Yu, Massinque, Mdala, Moidaki, Mutamina, Atekwana, Ingate, ReuschSeismic arrays to study African Rift initiation.EOS Transaction of AGU, Vol. 94, 24, June 11, pp. 213-214.Africa, southern AfricaGeophysics - seismics
DS200912-0477
2009
Massol, H.Massol, H., Jaupart, C.Dynamics of magma flow near the vent: implications for dome eruptions.Earth and Planetary Science Letters, Vol. 279, 3-4, pp. 185-196.MantleMagmatism
DS1996-1555
1996
Masson, F.Wittlinger, G., Masson, F., et al.Seismic tomography of north Tibet and Kunlun: evidence for crustal blocksand mantle velocity contrastsEarth and Planetary Science Letters, Vol. 139, pp. 2630279.China, TibetTomography, Mantle tectonics, blocks
DS2000-0241
2000
Masson, F.Dorbath, C., Masson, F.Composition of crust and upper mantle in Central Andes: inferred from P wave velocity and Poisson's ratio.Tectonophysics, Vol. 327, No. 3-4, Dec.15, pp. 213-224.South America, AndeanLithosphere, Geophysics - seismics
DS2002-1738
2002
Masson, N.J.G.Woolett, A.C., Masson, N.J.G.,Stone, K.M.Jabali / Yanbu - a new source of zinc in the middle eastSme Preprint, No. 02-123, 9p.YemenZinc, Deposit - Jabali
DS200812-0787
2008
MassoneNasir, S., Al-Khirbash, Rollinson, Al-Harthy, Al-Sayigh, Al-Lazki, Belousa, Kaminsky, Theye, Massone, Al-BuaidiEvolved carbonatitic kimberlite from the Batain Nappes, eastern Oman continental margin.9IKC.com, 3p. extended abstractAfrica, Arabia, OmanPetrography
DS200812-0788
2008
MassoneNasir, S., Al-Khirbash, Rollinson, Al-Harthy, Al-Sayigh, Al-Lazki, Belousa, Kaminsky, Theye, Massone, Al-BuaidiLate Jurassic Early Cretaceous kimberlite, carbonatite and ultramafic lamprophyric sill and dyke swarms from the Bomethra area, northeastern Oman.9IKC.com, 3p. extended abstractAfrica, Arabia, OmanPetrography
DS1995-1175
1995
Massone, H.J.Massone, H.J., Grosch, U.P-T evolution of Paleozoic garnet peridotites from the Saxonian Erzebirgeand the Aheim region, W. Norway.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 353-355.NorwayPeridotites, Erzebirge and Aheim regions
DS1999-0446
1999
Massone, H.J.Massone, H.J.A new occurrence of microdiamonds in quartzofeldspathic rocks of the Saxonian Erzgebirge, metamorphic evolution7th International Kimberlite Conference Nixon, Vol. 2, pp. 533-39.GermanyMicro diamonds, metamorphism
DS2000-0626
2000
Massone, H.J.Massone, H.J., Dobrzhinetskaya, L., Green, H.W.Quartz Potassium feldspar intergrowths enclosed in eclogitic garnet and omphacite. are pseudomorphs after coesite?Igc 30th. Brasil, Aug. abstract only 4p.Globalmetamorphism, Dabie Shan
DS2000-1000
2000
Massone, H.J.Wang, Q., Massone, H.J.Fluids released from exhuming dry eclogites, Dabie Shan ChinaIgc 30th. Brasil, Aug. abstract only 1p.ChinaEclogites, Dabie Shan area
DS2002-1006
2002
Massone, H.J.Massone, H.J., Bautsch, H.J.An unusual garnet pyroxenite from the Granulitgebirge, Germany: origin in the transition zone ( >400 km depth) or in a shallower upper mantle region?International Geology Review, Vol. 44, 9, pp. 779-96.GermanyPyroxenite - petrology
DS2003-0810
2003
Massone, H.J.Li, Q., Li, S., Zheng, Y.F., Li, H., Massone, H.J., Wang, Q.A high precision U Pb age of metamorphic rutile in coesite bearing eclogite from theChemical Geology, Vol. 200, 3-4, pp. 255-65.ChinaUHP, geochronology
DS2003-0888
2003
Massone, H.J.Massone, H.J., Nasdala, L.Characterization of an early metamorphic stage through inclusions in zircon of aAmerican Mineralogist, Vol. 88, 5/6, pp. 883-889.GermanyDiamond - microdiamonds
DS200412-1128
2003
Massone, H.J.Li, Q., Li, S., Zheng, Y.F., Li, H., Massone, H.J., Wang, Q.A high precision U Pb age of metamorphic rutile in coesite bearing eclogite from the Dabie Mountains in central China: a new conChemical Geology, Vol. 200, 3-4, pp. 255-65.ChinaUHP, geochronology
DS200412-1242
2003
Massone, H.J.Massone, H.J., Nasdala, L.Characterization of an early metamorphic stage through inclusions in zircon of a Diamondiferous quartzofeldspathic rock from theAmerican Mineralogist, Vol. 88, 5/6, pp. 883-889.Europe, GermanyDiamond - microdiamonds
DS2003-1199
2003
Massone, H-J.Sabau, G., Massone, H-J.Relationships among eclogite bodies and host rocks in the Lotru metamorphic suite (International Geology Review, Vol. 45, 3, March, pp. 225-262.RomaniaEclogites, Tectonics
DS200412-0464
2003
Massone, H-J.Dobrzhinetskaya, L.F., Green, H.W., Weschler, M., Darus, M., Young-Chung, Wang, Massone, H-J., Stockhert, B.Focused ion beam technique and transmission electron microscope studies of microdiamonds from the Saxonian Erzgerbirge, Germany.Earth and Planetary Science Letters, Vol. 210, 3-4, May 30, pp.399-410.Europe, GermanyDiamond inclusions
DS200512-0692
2005
Massone, H-J.Massone, H-J.Involvement of crustal material in delamination of the lithosphere after continent-continent collision.International Geology Review, Vol. 47, 7, pp. 792-804.MantleTectonics
DS200712-0692
2007
Massone, H-J.Massone, H-J., Czambor, A.Geochemical signatures of Variscan eclogites from the Saxonian Erzgebirge central Europe.Chemie der Erde, Vol. 67, 1, pp.69-83.EuropeEclogite
DS200912-0531
2009
Massone, H-J.Nasir, S., Theye, T., Massone, H-J.REE rich aeschynite in apatite dolomite carbonatite, Oman Mountains.The Open Mineralogy Journal, Vol. 3, pp. 17-27.Africa, Arabia, OmanCarbonatite
DS201312-0228
2013
Massone, H-J.Dristas, J.A., Martinez, J-C., Massone, H-J., Pimentel, M.M.Mineralogical and geochemical characterization of a rare ultramafic lamprophyre in the Tandilia belt basement, Rio de la Plata, Argentina.Journal of South American Earth Sciences, Vol. 43, pp. 46-61.South America, ArgentinaLamprophyre
DS201611-2126
2016
Massone, J-J.Nasdala, L., Dobrzhinetskaya, L.F., Korsakov, A.V., Massone, J-J., Reissner, C.UHP phases versus preparation materials - be cautious when using micro-raman spectroscopy.European Mineralogical Conference held Sept. 11-15, Italy, p. 219. abstract 1p.TechnologyRaman Spectroscopy
DS1998-0956
1998
Massonet, D.Massonet, D., Feigl, K.L.Radar interferometry and its application to changes in the earth'ssurface.Reviews of Geophysics, Vol. 36, No. 4, Nov. pp. 441-500.GlobalRemote sensing, Radar - general review not specific to diamonds
DS201112-0724
2011
MassonneNasir, S., Al-Khirbash, S., Rollinson, H., Al-Harthy, Al-Sayigh, Al-Lazki, Theye, Massonne, BelousovaPetrogenesis of early Cretaceous carbonatite and ultramafic lamprophyres in a diatreme in the Batain Nappes, eastern Oman continental margin.Contributions to Mineralogy and Petrology, Vol. 161, 1, pp. 47-74.Asia, OmanCarbonatite
DS1990-0994
1990
Massonne, H.J.Massonne, H.J.Phengite geobarometry applied to eclogitic rocksTerra, Abstracts of Crustal Dynamics: Pathways and Records held Bochum FRG, Vol. 2, December p. 31GlobalEclogites, Geobarometry
DS1998-0957
1998
Massonne, H.J.Massonne, H.J.A new occurrence of microdiamonds in quartzofeldspathic rocks of the Saxonian Erzgebirge - metamorphic evol.7th International Kimberlite Conference Abstract, pp. 552-4.GermanyMineral chemistry - microdiamonds, Metamorphic evolution
DS1998-0958
1998
Massonne, H.J.Massonne, H.J., Berhardt, H.J., Westphal, T.Simple identification and quantification of microdiamonds in rock thinsections.European Journal of Mineralogy, Vol. 10, No. 3, May 1, pp. 497-504.GlobalPetrology, Microdiamonds
DS2001-0736
2001
Massonne, H.J.Massonne, H.J.First find of coesite in the ultrahigh pressure metamorphic area of the central Erzgebirge.European Journal of Mineralogy, Vol. 13, No. 3, pp. 565-70.Germanyultra high pressure (UHP), Coesite
DS2003-0889
2003
Massonne, H.J.Massonne, H.J.A comparison of the evolution of Diamondiferous quartz rich rocks from the SaxonianEarth and Planetary Science Letters, Vol. 216, 3, pp. 347-64.RussiaGenesis - metamorphic
DS200412-1243
2003
Massonne, H.J.Massonne, H.J.A comparison of the evolution of Diamondiferous quartz rich rocks from the Saxonian Erzgebirge and the Kokchetav Massif: are soEarth and Planetary Science Letters, Vol. 216, 3, pp. 347-64.RussiaGenesis - metamorphic
DS200812-0719
2007
Massonne, H.J.Massonne, H.J., Kennedy, A., Nasdala, L., Theya, T.Dating of zircon and monazite from Diamondiferous quartsofeldapathic rocks of the Saxonian Erzebirge hints at burial and exhumation veolocities.Mineralogical Magazine, Vol. 71, 4, pp. 407-425.Europe, GermanyGeochronology
DS200912-0865
2009
Massonne, H.J.Zhou, Y.F., Massonne, H.J., Zhu, M.F.Petrology of low temperature, ultra high pressure marbles and interlayered coesite eclogites near Sanqingge, Sulu terrane, eastern China.Mineralogical Magazine, Vol.73, 2, April, pp. 3-7-332.ChinaUHP
DS2001-1133
2001
Massonne, HJ.Stockhert, B., Duyster, J., Trepmann, C., Massonne, HJ.Microdiamond daughter crystals precipitated from supercritical COH + silicate fluids included garnet...Geology, Vol. 29, No. 5, May, pp. 391-4.GermanyDiamond, ultra high pressure (UHP), metamorphism, Erzgebirge area
DS2003-1200
2003
Massonne, H-J.Sabau, G., Massonne, H-J.Relationships among eclogite bodies and host rocks in the Lotru metamorphic suite (International Geology Review, Vol. 45, 3, Mar. pp. 225-262.RomaniaBlank
DS200412-1713
2003
Massonne, H-J.Sabau, G., Massonne, H-J.Relationships among eclogite bodies and host rocks in the Lotru metamorphic suite ( South Carpathians) Romania: petrological eviInternational Geology Review, Vol. 45, 3, Mar. pp. 225-262.Europe, RomaniaEclogite
DS200712-0693
2007
Massonne, H-J.Massonne, H-J., Tu, W.13C signature of early graphite and subsequently formed microdiamond from the Sxonian Erzgebirge, Germany.Terra Nova, Vol. 19, 6, pp. 476-480.Europe, GermanyMicrodiamonds
DS201212-0449
2012
Massonne, H-J.Massonne, H-J.Formation of amphibole and clinozoisite epidote in eclogite owing to fluid infiltration during exhumation in a subduction channel.Journal of Petrology, Vol. 53, 10, pp. 1969-1998.MantleSubduction, magmatism
DS201312-0584
2013
Massonne, H-J.Massonne, H-J.Constructing the pressure temperature path of ultrahigh pressure rocks.Elements, Vol. 9, 4, August in pressMantleUHP
DS201605-0868
2016
Massonne, H-J.Massonne, H-J.Hydration of lithospheric mantle by the descending plate in a continent collisional setting and its geodynamic consequences.Journal of Geodynamics, Vol. 96, pp. 50-61.MantleOrogen - subduction

Abstract: At the beginning of continent-continent collision the descending plate dehydrates. The influence of this dehydration on the adjacent lithospheric mantle was studied. For this reason, pressure (P), temperature (T) and T-H2O pseudosections were calculated for an average mantle composition using the computer software PERPLE_X. These pseudosections were contoured by isopleths, for instance, for volumes of amphibole, chlorite, and serpentine. In addition, P-T pseudosections were considered for four psammopelitic rocks, common in the upper portion of the continental crust, in order to quantify the release of H2O in these rocks during prograde metamorphism. At pressures around 1 GPa, a maximum of slightly more than 10 vol.% chlorite, almost 20 vol.% amphibole, and some talc but no serpentine forms when only 1.8 wt.% H2O is added to the dry ultrabasite at temperatures of 600 °C. For example, hydrous phases amount to about 35 vol.% serpentine and 10 vol.% each of chlorite and amphibole at 1 GPa, 550 °C, and 5 wt.% H2O. The modelled psammopelitic rocks can release 0.8-2.5 wt.% H2O between 450 and 650 °C at 0.8-1.4 GPa. On the basis of the above calculations, different collisional scenarios are discussed highlighting the role of hydrated lithospheric mantle. In this context a minimum hydration potential of the front region of the descending continental plate is considered, which amounts to 4.6 × 1016 kg releasable H2O for a 1000 km wide collisional zone, due to a thick sedimentary pile at the continental margin. Further suggestions are that (1) the lower crustal plate in a continent-continent collisional setting penetrates the lithospheric mantle, which is hydrated during the advancement of this plate, (2) the maximum depths of the subduction of upper continental crust is below 70 km and (3) hydrated mantle above the descending crustal plate is thrust onto this continental crust.
DS201704-0635
2017
Massonne, H-J.Liu, P., Massonne, H-J., Zhang, J., Wu, Y., Jin, Z.Intergranular coesite inclusions in dolomite from the Dabie Shan: constraints on the preservation of coesite in UHP rocks.Terra Nova, in press availableChinaCoesite

Abstract: Intergranular coesite is extremely rare in, and bears crucial information on the formation and preservation of, ultrahigh-pressure (UHP) rocks. Here, we report the first occurrence of intergranular coesite in a metasedimentary rock, which occurs in the Ganjialing area in the Dabie Shan, east-central China, and contains abundant coesite inclusions in both garnet and dolomite. We investigated the content of structural water in these minerals with Fourier transform infrared spectroscopy. Our new results undermine the ubiquity of the “pressure-vessel” model and highlight the role of reaction kinetics in preserving coesite due to the availability of water in UHP rocks.
DS201811-2591
2018
Massonne, H-J.Liu, P., Zhang, J., Massonne, H-J., Jin, Z.Polyphase solid-inclusions formed by interactions between infiltrating fluids and precursor minerals enclosed in garnet of UHP rocks from the Dabie Shan, China.American Mineralogist, Vol. 103, pp. 1663-1673.Chinacoesite

Abstract: Three types of polyphase solid-inclusions (PSIs) with distinct mineral assemblages and micro-structures were found in garnet of an ultrahigh-pressure (UHP) eclogite-vein system from the Dabie Shan, east-central China. Type-1 PSI contains variable volumes of quartz, K-feldspar, plagioclase ± other phases, whereas Type-2 PSI contains variable volumes of quartz, calcite ± other phases. Both types display shapes that are compatible with those of euhedral coesite inclusions. Type-3 PSI always contains a rutile core that is surrounded by plagioclase ± quartz and generally displays the morphology of the rutile core. Variable amounts of K-feldspar are embedded within the plagioclase of Type-3 PSIs. The three PSI types developed fluid-mediated microstructures that include wedge-like offshoot and protrusion textures and inclusion-garnet interfaces controlled by the crystallographic structure of garnet. PSIs in peak minerals of UHP rocks have been previously thought to represent primary supercritical fluid or melt inclusions. Here we propose that the studied PSIs were formed under high-pressure (HP) eclogite-facies conditions during exhumation and represent reaction products between an enclosed mineral, such as coesite and rutile, and external fluids infiltrating the host garnet along fractures that have been healed later on. Two immiscible aqueous fluids (i.e., a siliceous and a carbonaceous) were involved in the formation of these PSIs. The siliceous fluid was rich in various large ion lithophile elements like Cs, Rb, Ba, K, Pb, Li, and Sr, whereas the carbonaceous fluid was rich in Pb and Sr. The new PSI formation mechanism proposed in this study brings significant implications for tracing fluid evolution and post-entrapment modifications of mineral inclusions in HP and UHP metamorphic rocks.
DS201901-0004
2018
Massonne, H-J.Artyushkov, E.V., Korikovsky, S.P., Massonne, H-J., Checkhovich, P.A.Recent crustal uplift of Precambrian cratons: key patterns and possible mechanisms.Russian Geology and Geophysics, Vol. 59, 11, pp. 1389-1409.Russiacraton

Abstract: Precambrian cratons cover about 70% of the total continental area. According to a large volume of geomorphological, geological, paleontological, and other data for the Pliocene and Pleistocene, these cratons have experienced a crustal uplift from 100-200 m to 1000-1500 m, commonly called the recent or Neotectonic uplift. Shortening of the Precambrian crust terminated half a billion years ago or earlier, and its uplift could not have been produced by this mechanism. According to the main models of dynamic topography in the mantle, the distribution of displacements at the surface is quite different from that of the Neotectonic movements. According to seismic data, there is no magmatic underplating beneath most of the Precambrian cratons. In most of cratonic areas, the mantle lithosphere is very thick, which makes its recent delamination unlikely. Asthenospheric replacement of the lower part of the mantle lithosphere beneath the Precambrian cratons might have produced only a minor part of their Neotectonic uplifts. Since the above mechanisms cannot explain this phenomenon, the rock expansion in the crustal layer is supposed to be the main cause of the recent uplift of Precambrian cratons. This is supported by the strong lateral nonuniformity of the uplift, which indicates that expansion of rocks took place at a shallow depth. Expansion might have occurred in crustal rocks that emerged from the lower crust into the middle crust with lower pressure and temperature after the denudation of a thick layer of surface rocks. In the dry state, these rocks can remain metastable for a long time. However, rapid metamorphism accompanied by expansion of rocks can be caused by infiltration of hydrous fluids from the mantle. Analysis of phase diagrams for common crustal rocks demonstrates that this mechanism can explain the recent crustal uplift of Precambrian cratons.
DS202012-2229
2020
Massonne, H-J.Massonne, H-J., Li, B.Zoning of eclogitic garnet cores - a key pattern demonstrating the dominance of tectonic erosion as part of the burial process of worldwide occurring eclogites.Earth-Science Reviews, Vol. 210, 103356 27p. PdfMantleeclogites
DS202102-0206
2020
Massonne, H-J.Massonne, H-J., Li, B.Zoning of eclogitic garnet cores - a key pattern demonstrating the dominance of tectonic erosion as part of the burial process of worldwide occurring eclogites.Earth-Science Reviews, Vol. 210, doi.org/10.1016 /j.earscirev.2020. 103356 27p. Pdf MantleUHP, geodynamics

Abstract: Eclogites are witnesses of geodynamic processes that are commonly related to subduction of oceanic crust. Information on the part of these processes that refers to the burial of this rock type is rarely published but stored in the eclogitic garnet core and inclusions therein. To better understand general aspects of the burial process, a literature search on the chemical characteristics of garnet in worldwide occurrences of eclogite was undertaken. In most cases extended garnet cores show either a prograde growth zoning with increasing Mg, starting at a few percent of pyrope component, and decreasing Mn contents (type I eclogite) or a (nearly) constant chemical composition frequently with pyrope contents significantly above 10 percent (eclogites of types II and III). Only in minor cases, it is difficult to assign the reported garnet core to an eclogite type. The growth zoning of garnet was thermodynamically modelled for the chemical composition of a basalt following different burial paths. These paths are characterized either by a trajectory along a low geothermal gradient (type I eclogite), as expected for the subducting upper portion of oceanic crust, or a one characterized by nearly isothermal burial at temperatures above 500 °C reaching peak pressures up to 2.1 GPa (type III eclogite), as possibly due to crustal thickening during continent-continent collision, or more (type II eclogite) when basic rocks are tectonically eroded from the overriding continental plate before deep subduction. In addition, diffusion modelling was undertaken on mm-sized garnet demonstrating that the characteristics of the core zoning are not fully obliterated even during residence at temperatures of 800-850 °C within 10 million years. The scrutiny of more than 200 eclogites reported in the literature led to the following result: about half of them are type II eclogites; a third and a sixth can be related to type I and type III, respectively. Among type III are almost all of the few Proterozoic eclogites considered. To demonstrate the benefit of our study, we link the core zoning of eclogitic garnet from various (ultra)high-pressure terranes in Phanerozoic orogenic belts to the geodynamics shaping corresponding orogens. The eclogites in these belts are dominated by type II. Thus, we propose that some of the material of the lower portion of the overriding continental crust was tectonically eroded by a subducted oceanic plate and brought to great depth. Afterwards, this material was exhumed first in a deep subduction channel and then in an exhumation channel during continent-continent collision where a contact with the upper continental plate was re-established. Furthermore, we suggest that type II eclogite can also occur in extrusion wedges as far as oblique subduction took place.
DS202204-0529
2022
Massonne, H-J.Massonne, H-J., Fockenberg, T.Melting of phengite-bearing eclogite at pressures of 4 and 9 GPA relevant to deep regions of a subduction zone.Earth and Planetary Science Letters, Vol. 584, 14p. 117475Mantlesubduction

Abstract: Melting experiments undertaken with finely ground powder of phengite-bearing eclogite yielded solidus temperatures of about 970 °C at 4 GPa and 1250 °C at 9 GPa. Additional experiments with a rock powder of psammopelitic composition established a solidus at 9 GPa at a temperature of 1350 °C. Initial melts produced from both rocks are rich in potassium. The melts generated from eclogite tend to become richer in Na and Ca with rising temperature due to increasing decomposition of clinopyroxene. At the maximum temperatures of the experiments with eclogite, up to 450 °C above the solidus at 4 GPa, this phase is still present in the restite together with abundant garnet. In the temperature interval of 1100-1300 °C, when 22-30% of the studied eclogite was melted, the melts are quartz monzonitic in composition. According to the reported experimental results, we suggest that partial melting of oceanic crust is unlikely in a subduction zone. However, ascending melange diapirs, composed of material from the upper portion of a deep-seated subducted oceanic slab, can partially melt in the hot mantle wedge. The thus generated melts further ascend to contribute to lavas of magmatic arc systems.
DS1930-0115
1932
Massot, M.Massot, M.Au Pays de L'or et du DiamantParis: Ed. Des Portiques, 253P.South AfricaKimberley, Janlib, Travelogue
DS201412-0600
2014
Massuyeau, M.Moussallam, Y., Morizet, Y., Massuyeau, M., Laumonier, M.COs solubility in kimberlite melts.Chemical Geology, 33p.MantleMelting
DS201510-1786
2015
Massuyeau, M.Massuyeau, M., Gardes, E., Morizet, Y., Gaillard, F.A model for the activity of silica along the carbonatite-kimberlite-mellilitite-basanite melt compositional joint.Chemical Geology, Vol. 418, pp. 206-216.TechnologyKimberlite

Abstract: Carbon dioxide and water, being present in the Earth's mantle at concentration levels of tens to hundreds of ppm, greatly lower the peridotite solidus temperature and drastically modify the composition of produced melts. The presence of CO2 produces silica-poor, carbonate-rich liquids at the onset of melting, and these liquids shift toward silica rich compositions as the degree of melting increases. Numerous geochemical observations and experimental studies have revealed the complexity of the transition between carbonate-rich and silicate-rich melts. It is characterized by a strongly non-linear evolution and, under specific conditions, by immiscibility. To better constrain this transition, we have used the thermodynamic activity of silica as a probe of the mixing properties between molten carbonate and molten silicate. The activity of silica (aSiO2(l))aSiO2l was calculated for a large number of experimental liquids from two equilibria: olivine-orthopyroxene-melt and immiscible silicate-rich melt-carbonate-rich melt (491 data points ranging from 1 to 14 GPa and 1090 to 1800 °C). We modelled aSiO2(l)aSiO2l during incipient melting of the peridotite in presence of CO2 with a generalized Margules function. Our model reproduces well the silica activity-composition relationships of the experimental database, and can be used to predict the silica content of the melts coexisting with olivine and orthopyroxene. We show that water content and Ca/Mg ratio in the melts have an important influence on the aSiO2(l)aSiO2l. In contrast to a recent empirical model (Dasgupta et al., 2013), the analysis of the experimental database reveals that the transition from carbonate to silicate melt with decreasing depth should occur abruptly in oceanic mantle. Our model predicts that carbonatitic melts with ~ 5 wt.% SiO2 can be stabilized from ~ 150 km depth, at the onset of incipient melting by "redox melting", up to ~ 75 km, above which the liquid evolves abruptly to a carbonated silicate composition (> ~ 25 wt.% SiO2). In the cratonic mantle lithosphere, our model predicts that carbonatitic melts are prevailing up to shallow depth, and conflicts the recent model (Russell et al., 2012) of CO2-saturation triggered by orthopyroxene assimilation during kimberlite ascent.
DS201603-0403
2015
Massuyeau, M.Moussallam, Y., Morizet, Y., Massuyeau, M., Laumonier, M., Gaillard, F.CO ( sub 2) solubility in kimberlite melts.Chemical Geology, Vol. 418, pp. 198-205.MantleExperimental Petrology

Abstract: Carbon dioxide is the most abundant volatile in kimberlite melts and its solubility exerts a prime influence on the melt structure, buoyancy, transport rate and hence eruption dynamics. The actual primary composition of kimberlite magma is the matter of some debate but the solubility of CO2 in kimberlitic melts is also poorly constrained due to difficulties in quenching these compositions to a glass that retains the equilibrium CO2 content. In this study we used a range of synthetic, melt compositions with broadly kimberlitic to carbonatitic characteristics which can, under certain conditions, be quenched fast enough to produce a glass. These materials are used to determine the CO2 solubility as a function of chemical composition and pressure (0.05-1.5 GPa). Our results suggest that the solubility of CO2 decreases steadily with increasing amount of network forming cations from ~ 30 wt.% CO2 at 12 wt.% SiO2 down to ~ 3 wt.% CO2 at 40 wt.% SiO2. For low silica melts, CO2 solubility correlates non-linearly with pressure showing a sudden increase from 0.1 to 100 MPa and a smooth increase for pressure > 100 MPa. This peculiar pressure-solubility relationship in low silica melts implies that CO2 degassing must mostly occur within the last 3 km of ascent to the surface having potential links with the highly explosive nature of kimberlite magmas and some of the geo-morphological features of their root zone. We present an empirical CO2 solubility model covering a large range of melt composition from 11 to 55 wt.% SiO2 spanning the transition from carbonatitic to kimberlitic at pressures from 1500 to 50 MPa.
DS201612-2277
2016
Massuyeau, M.Aulbach, S., Massuyeau, M., Gaillard, F.Origins of cratonic mantle discontinuities: a view from petrology, geochemistry and thermodynamic models.Lithos, in press available 74p.GlobalCraton

Abstract: Geophysically detectible mid-lithospheric discontinuities (MLD) and lithosphere-asthenosphere boundaries (LAB) beneath cratons have received much attention over recent years, but a consensus on their origin has not yet emerged. Cratonic lithosphere composition and origin is peculiar due to its ultra-depletion during plume or accretionary tectonics, cool present-day geothermal gradients, compositional and rheological stratification and multiple metasomatic overprints. Bearing this in mind, we integrate current knowledge on the physical properties, chemical composition, mineralogy and fabric of cratonic mantle with experimental and thermodynamic constraints on the formation and migration of melts, both below and within cratonic lithosphere, in order to find petrologically viable explanations for cratonic mantle discontinuities. LABs characterised by strong seismic velocity gradients and increased conductivity require the presence of melts, which can form beneath intact cratonic roots reaching to ~ 200-250 km depth only in exceptionally warm and/or volatile-rich mantle, thus explaining the paucity of seismical LAB observations beneath cratons. When present, pervasive interaction of these - typically carbonated - melts with the deep lithosphere leads to densification and thermochemical erosion, which generates topography at the LAB and results in intermittent seismic LAB signals or conflicting seismic, petrologic and thermal LAB depths. In rare cases (e.g. Tanzanian craton), the tops of live melt percolation fronts may appear as MLDs and, after complete lithosphere rejuvenation, may be sites of future, shallower LABs (e.g. North China craton). Since intact cratons are presently tectonomagmatically quiescent, and since MLDs produce both positive and negative velocity gradients, in some cases with anisotropy, most MLDs may be best explained by accumulations (metasomes) of seismically slow minerals (pyroxenes, phlogopite, amphibole, carbonates) deposited during past magmatic-metasomatic activity, or fabric inherited from cratonisation. They may accumulate as layers at, or as subvertical veins above, the depth at which melt flow transitions from pervasive to focussed flow at the mechanical boundary layer, causing azimuthal and radial anisotropy. Thermodynamic calculations investigating the depth range in which small-volume melts can be produced relative to the field of phlogopite stability and the presence of MLDs show that phlogopite precipitates at various pressures as a function of age-dependent thermal state of the cratonic mantle, thus explaining variable MLD depths. Even if not directly observed, such metasomes have been shown to be important ingredients in small-volume volatile-rich melts typically penetrating cratonic lithospheres. The apparent sparseness of evidence for phlogopite-rich assemblages in the mantle xenolith record at geophysically imaged MLD depths, if not due to preferential disaggregation in the kimberlite or alteration, may relate to vagaries of both kimberlite and human sampling.
DS201801-0070
2018
Massuyeau, M.Tappe, S., Smart, K., Torsvik, T., Massuyeau, M., de Wit, M.Geodynamics of kimberlites on a cooling Earth: clues to plate tectonic evolution and deep volatile cycles.Earth and Planetary Science Letters, Vol. 484, pp. 1-14.Mantlekimberlite, origin, magmatism

Abstract: Kimberlite magmatism has occurred in cratonic regions on every continent. The global age distribution suggests that this form of mantle melting has been more prominent after 1.2 Ga, and notably between 250-50 Ma, than during early Earth history before 2 Ga (i.e., the Paleoproterozoic and Archean). Although preservation bias has been discussed as a possible reason for the skewed kimberlite age distribution, new treatment of an updated global database suggests that the apparent secular evolution of kimberlite and related CO2-rich ultramafic magmatism is genuine and probably coupled to lowering temperatures of Earth's upper mantle through time. Incipient melting near the CO2- and H2O-bearing peridotite solidus at >200 km depth (1100-1400?°C) is the petrologically most feasible process that can produce high-MgO carbonated silicate melts with enriched trace element concentrations akin to kimberlites. These conditions occur within the convecting asthenospheric mantle directly beneath thick continental lithosphere. In this transient upper mantle source region, variable CHO volatile mixtures control melting of peridotite in the absence of heat anomalies so that low-degree carbonated silicate melts may be permanently present at ambient mantle temperatures below 1400?°C. However, extraction of low-volume melts to Earth's surface requires tectonic triggers. Abrupt changes in the speed and direction of plate motions, such as typified by the dynamics of supercontinent cycles, can be effective in the creation of lithospheric pathways aiding kimberlite magma ascent. Provided that CO2- and H2O-fluxed deep cratonic keels, which formed parts of larger drifting tectonic plates, existed by 3 Ga or even before, kimberlite volcanism could have been frequent during the Archean. However, we argue that frequent kimberlite magmatism had to await establishment of an incipient melting regime beneath the maturing continents, which only became significant after secular mantle cooling to below 1400?°C during post-Archean times, probably sometime shortly after 2 Ga. At around this time kimberlites replace komatiites as the hallmark mantle-derived magmatic feature of continental shields worldwide. The remarkable Mesozoic-Cenozoic ‘kimberlite bloom’ between 250-50 Ma may represent the ideal circumstance under which the relatively cool and volatile-fluxed cratonic roots of the Pangea supercontinent underwent significant tectonic disturbance. This created more than 60% of world's known kimberlites in a combination of redox- and decompression-related low-degree partial melting. Less than 2% of world's known kimberlites formed after 50 Ma, and the tectonic settings of rare ‘young’ kimberlites from eastern Africa and western North America demonstrate that far-field stresses on cratonic lithosphere enforced by either continental rifting or cold subduction play a crucial role in enabling kimberlite magma transfer to Earth's surface.
DS201909-2065
2019
Massuyeau, M.Nabyl, Z., Massuyeau, M., Gaillard, F., Tuduri, J., Iacono-Marziano, G., Rogerie, G., Le Trong, E., Di Carlo, I., Melleton, J., Bailly, L.REE-rich carbonatites immiscible with phonolitic magma.Goldschmidt2019, 1p. AbstractGlobalcarbonatite - REE

Abstract: uncommon type of magmatic rocks dominates by carbonate, are broadly enriched in rare earth elements (REE) relative to the majority of igneous silicate rocks. While more than 500 carbonatites are referenced worldwide [1], only a few contain economic REE concentrations that are widely considered as resulting from late magmatic-hydrothermal or supergene processes. Magmatic pre-enrichment, linked to the igneous processes at the origin of carbonatites, are, however, likely to contribute to the REE fertilisation. Field observations [1] and experimental surveys [2, 3] suggest that a large part of the carbonatite melts can be produced as immiscible liquids with silicate magmas. Experimental constraints reveals that such immiscibility processes can lead to both REE enrichments and depletions in carbonatites [2, 3], making the magmatic processes controlling REE enrichments unclear. Here we present results of high-pressure and hightemperature experiments, simultaneously addressing crystal fractionation of alkaline magmas and immiscibility between carbonate and silicate melts. The experimental data reveal that the degree of differentiation, controlling the chemical composition of alkaline melts is a key factor ruling the REE concentration of the coexisting immiscible carbonatites. The parameterization of the experimental data together with the compilation of geochemical data from various alkaline provinces show that REE concentrations similar to those of highly REE enriched carbonatites (?REE > 30000 ppm) can be produced by immiscibility with phono-trachytic melt compositions, while more primitive alkaline magma can only be immiscible with carbonatites that are not significantly enriched in REE.
DS202006-0940
2020
Massuyeau, M.Nabyl, Z., Massuyeau, M., Gaillard, F., Tuduri, J., Iacono-Marziano, G., Rogerie, G., Le Trong, E., Di Carlo, I., Melleton, J., Bailly, L.A window in the course of alkaline magma differentiation conducive to immiscible REE-rich carbonatites.Geochimica et Cosmochimica Acta, in press available 57p. PdfMantlecarbonatite

Abstract: Rare earth element (REE) enrichments in carbonatites are often described as resulting from late magmatic-hydrothermal or supergene processes. However, magmatic pre-enrichment linked to the igneous processes at the origin of carbonatites are likely to contribute to the REE fertilisation. Experimental constraints reveals that immiscibility processes between carbonate and silicate melts can lead to both REE enrichments and depletions in carbonatites making the magmatic processes controlling REE enrichments unclear. We link REE contents of carbonatites to the magmatic stage at which carbonatites are separated from silicate magma in their course of differentiation. We present results of experiments made at pressure and temperature conditions of alkaline magmas and associated carbonatites differentiation (0.2-1.5 GPa; 725-975?°C; FMQ to FMQ?+?2.5), simultaneously addressing crystal fractionation of alkaline magmas and immiscibility between carbonate (calcio-carbonate type) and silicate melts (nephelinite to phonolite type). The experimental data shows that the degree of differentiation, controlling the chemical composition of alkaline melts, is a key factor ruling the REE concentration of the coexisting immiscible carbonate melts. In order to predict carbonate melt REE enrichments during alkaline magma differentiation, we performed a parameterisation of experimental data on immiscible silicate and carbonate melts, based exclusively on the silica content, the alumina saturation index and the alkali/alkaline-earth elements ratio of silicate melts. This parameterisation is applied to more than 1600 geochemical data of silicate magmas from various alkaline provinces (East African Rift, Canary and Cape Verde Islands) and show that REE concentrations of their potential coeval carbonatite melts can reach concentration ranges similar to those of highly REE enriched carbonatites (?REE?>?30 000?ppm) by immiscibility with phonolitic/phono-trachytic melt compositions, while more primitive alkaline magmas can only be immiscible with carbonatites that are not significantly enriched in REE.
DS202009-1643
2020
Massuyeau, M.Nabyl, Z., Massuyeau, M.,Gaillard, F., Tuduri, J., Gregory, G-M., Trong, E., Di Carlo, I., Melleton, J., Bailly, L. A window in the course of alkaline magma differentiation conducive to immiscible REE-rich carbonatite.Geochimica et Cosmochimica Acta, Vol. 282, pp. 297-323.Africa, East Africacarbonatites

Abstract: Rare earth element (REE) enrichments in carbonatites are often described as resulting from late magmatic-hydrothermal or supergene processes. However, magmatic pre-enrichment linked to the igneous processes at the origin of carbonatites are likely to contribute to the REE fertilisation. Experimental constraints reveals that immiscibility processes between carbonate and silicate melts can lead to both REE enrichments and depletions in carbonatites making the magmatic processes controlling REE enrichments unclear. We link REE contents of carbonatites to the magmatic stage at which carbonatites are separated from silicate magma in their course of differentiation. We present results of experiments made at pressure and temperature conditions of alkaline magmas and associated carbonatites differentiation (0.2-1.5 GPa; 725-975?°C; FMQ to FMQ?+?2.5), simultaneously addressing crystal fractionation of alkaline magmas and immiscibility between carbonate (calcio-carbonate type) and silicate melts (nephelinite to phonolite type). The experimental data shows that the degree of differentiation, controlling the chemical composition of alkaline melts, is a key factor ruling the REE concentration of the coexisting immiscible carbonate melts. In order to predict carbonate melt REE enrichments during alkaline magma differentiation, we performed a parameterisation of experimental data on immiscible silicate and carbonate melts, based exclusively on the silica content, the alumina saturation index and the alkali/alkaline-earth elements ratio of silicate melts. This parameterisation is applied to more than 1600 geochemical data of silicate magmas from various alkaline provinces (East African Rift, Canary and Cape Verde Islands) and show that REE concentrations of their potential coeval carbonatite melts can reach concentration ranges similar to those of highly REE enriched carbonatites (?REE?>?30 000?ppm) by immiscibility with phonolitic/phono-trachytic melt compositions, while more primitive alkaline magmas can only be immiscible with carbonatites that are not significantly enriched in REE.
DS202102-0190
2019
Massuyeau, M.Gaillard, F., Sator, N., Guillot, B., Massuyeau, M.The link between the physical and chemical properties of carbon-bearing melts and their application for geophysical imaging of Earth's mantleResearchgate , DOI: 10.1017/ 9781108677950.007 26p. Pdfmantlecarbon

Abstract: Significant investment in new capacities for experimental research at high temperatures and pressures have provided new levels of understanding about the physical properties of carbon in fluids and melts, including its viscosity, electrical conductivity, and density. This chapter reviews the physical properties of carbon-bearing melts and fluids at high temperatures and pressures and highlights remaining unknowns left to be explored. The chapter also reviews how the remote sensing of the inaccessible parts of the Earth via various geophysical techniques - seismic shear wave velocity, attenuation, and electromagnetic signals of mantle depths - can be reconciled with the potential presence of carbon-bearing melts or fluids.
DS202102-0207
2021
Massuyeau, M.Massuyeau, M., Gardes, E., Rogerie, G., Aulbach, S., Tappe, S., Le Trong, E., Sifre, D., Gaillard, F.MAGLAB: A computing platform connecting geophysical signatures to melting processes in Earth's mantle.Physics of the Earth and Planetary Interiors, doi.org/10.1016/ j.pepi.2020.106638 51p. PdfMantlegeophysics - magnetics

Abstract: Decompression melting of the upper mantle produces magmas and volcanism at the Earth's surface. Experimental petrology demonstrates that the presence of CO2 and H2O enhances peridotite melting anywhere within the upper mantle down to approximately 200-300?km depth. The presence of mantle melts with compositions ranging from carbonate-rich to silicate-rich unavoidably affects the geophysical signals retrieved from Earth's mantle. Geochemical investigations of erupted intraplate magmas along with geophysical surveys allow for constraining the nature and volume of primary melts, and a sound formalism is required to integrate these diverse datasets into a realistic model for the upper mantle including melting processes. Here, we introduce MAGLAB, a model developed to calculate the composition and volume fraction of melts in the upper mantle, together with the corresponding electrical conductivity of partially molten mantle peridotites at realistic pressure-temperature conditions and volatile contents. We use MAGLAB to show how the compositions of intraplate magmas relate to variations in lithosphere thickness. Progressive partial melting of a homogeneous peridotitic mantle source can in theory create the diversity of compositions observed among the spectrum of intraplate magma types, with kimberlite melts beneath thick continental shields, alkaline magmas such as melilitite, nephelinite and basanite beneath thinner continents and relatively old plus thick oceanic lithospheres, and ‘regular’ basalts beneath the youngest and thinnest oceanic lithospheres as well as beneath significantly thinned continental lithospheres. MAGLAB calculations support recent experimental findings about the role of H2O in the upper mantle on producing primary kimberlitic melts in addition to CO2. We demonstrate the robustness of MAGLAB calculations by reproducing the compositions of erupted melts as well as associated mantle electrical conductivities beneath the Society hotspot in the Pacific Ocean. A comparison of our simulations with magnetotelluric surveys at various oceanic settings shows that the heterogeneities in electrical conductivity of Earth's upper mantle are related to variations in volatile content via the presence of small (generally <<1?wt%) and heterogeneously distributed fractions of CO2-H2O-bearing melts.
DS202107-1141
2021
Massuyeau, M.Tappe, S., Massuyeau, M. , Smart, K.A., Woodland, A.B., Gussone, N., Milne, S., Stracke, A.Sheared peridotite and megacryst formation beneath the Kaapvaal Craton: a snapshot of tectonomagmetic processes across the lithosphere-asthenosphere transition.Journal of Petrology, 107p. In press availableAfrica, South Africacraton - Kaapvaal
DS202110-1638
2021
Massuyeau, M.Tappe, S., Smart, K., Massuyeau, M., Gussone, N.Sheared peridotite and megacryst formation beneath the Kaapvaal craton: a snapshot of tectonomagnetic processes across the lithosphere-asthenosphere transition.Journal of Petrology, Aug. 40p. Pdf research gateAfrica, South Africamagmatism

Abstract: The cratonic lithosphere-asthenosphere boundary is commonly invoked as the site of sheared peridotite and megacryst formation, a well-recognized petrological assemblage whose genetic relationships—if any—remain poorly understood. We have undertaken a comprehensive petrology and Sr-Nd-Hf-Ca isotope study of sheared peridotite xenoliths and clinopyroxene megacrysts from the c. 1150 Ma Premier kimberlite pipe on the central Kaapvaal craton in South Africa. New textural and mineral trace element evidence suggests that strong tectonic and magmatic overprinting affected the lower cratonic mantle over a vertical distance of ?50 km from the lithosphere-asthenosphere boundary located at ?200-225 km depth. Although modification of the central Kaapvaal cratonic mantle is commonly linked to the c. 2056 Ma Bushveld large igneous event, our thermobarometry, mantle redox, and Sr-Nd-Hf-Ca isotope data support a model in which volatile-rich low-volume melts and associated high-density fluids refertilized the lithosphere base shortly before or during asthenosphere-derived kimberlite and carbonatite magmatism at around 1150 Ma. This episode of lithospheric mantle enrichment was facilitated by exceptionally strong shear movements, as are recorded in the plastically deformed peridotites. We argue that stress-driven segregation of percolating carbonated melts contributed to megacryst formation along, or in close proximity to, shear zones within the cratonic mantle lithosphere. Integration of our results from the Kaapvaal craton and modern petrological concepts allows for the identification of a lithosphere-asthenosphere transition zone between ?150 and 225 km depth. This horizon is defined by intersections of the ?40-42 mW m-2 Premier paleogeotherm with (1) CO2-H2O-present solidus curves for peridotite (upper bound), and (2) typical mantle adiabats with potential temperatures between 1315 and 1420 °C (lower bound). At Premier, the most strongly deformed sheared peridotites occur mainly between ?160 and 185 km depth, firmly within the lithosphere-asthenosphere transition zone. Contrary to many previous models, we suggest that sheared peridotite formation occurs in localized deformation zones spaced out across the entire width of the lithosphere-asthenosphere transition zone, rather than being restricted to a single thin layer at the craton base where mantle flow causes viscous drag. Hence, plate-tectonic stresses acting on the lower cratonic lithosphere may be accommodated by extensive networks of shear zones, which provide transient pathways and sinks for percolating volatile-rich melts, linking the formation of megacrysts and sheared peridotites.
DS202111-1789
2021
Massuyeau, M.Tappe, S., Massuyeau, M., Smart, K.A., Woodland, A.B., Gussone, N., Milne, S., Stracke, A.Sheared peridotite and megacryst formation beneath the Kaapvaal craton: a snapshot of tectonomagmatic processes across the lithosphere-asthenosphere transition.Journal of Petrology, Vol. 62, 8, pp. 1-39. pdfAfrica, South Africadeposit - Premier, Cullinan

Abstract: The cratonic lithosphere-asthenosphere boundary is commonly invoked as the site of sheared peridotite and megacryst formation, a well-recognized petrological assemblage whose genetic relationships—if any—remain poorly understood. We have undertaken a comprehensive petrology and Sr-Nd-Hf-Ca isotope study of sheared peridotite xenoliths and clinopyroxene megacrysts from the c. 1150 Ma Premier kimberlite pipe on the central Kaapvaal craton in South Africa. New textural and mineral trace element evidence suggests that strong tectonic and magmatic overprinting affected the lower cratonic mantle over a vertical distance of ?50 km from the lithosphere-asthenosphere boundary located at ?200-225 km depth. Although modification of the central Kaapvaal cratonic mantle is commonly linked to the c. 2056 Ma Bushveld large igneous event, our thermobarometry, mantle redox, and Sr-Nd-Hf-Ca isotope data support a model in which volatile-rich low-volume melts and associated high-density fluids refertilized the lithosphere base shortly before or during asthenosphere-derived kimberlite and carbonatite magmatism at around 1150 Ma. This episode of lithospheric mantle enrichment was facilitated by exceptionally strong shear movements, as are recorded in the plastically deformed peridotites. We argue that stress-driven segregation of percolating carbonated melts contributed to megacryst formation along, or in close proximity to, shear zones within the cratonic mantle lithosphere. Integration of our results from the Kaapvaal craton and modern petrological concepts allows for the identification of a lithosphere-asthenosphere transition zone between ?150 and 225 km depth. This horizon is defined by intersections of the ?40-42 mW m-2 Premier paleogeotherm with (1) CO2-H2O-present solidus curves for peridotite (upper bound), and (2) typical mantle adiabats with potential temperatures between 1315 and 1420 °C (lower bound). At Premier, the most strongly deformed sheared peridotites occur mainly between ?160 and 185 km depth, firmly within the lithosphere-asthenosphere transition zone. Contrary to many previous models, we suggest that sheared peridotite formation occurs in localized deformation zones spaced out across the entire width of the lithosphere-asthenosphere transition zone, rather than being restricted to a single thin layer at the craton base where mantle flow causes viscous drag. Hence, plate-tectonic stresses acting on the lower cratonic lithosphere may be accommodated by extensive networks of shear zones, which provide transient pathways and sinks for percolating volatile-rich melts, linking the formation of megacrysts and sheared peridotites.
DS1991-1073
1991
Master, S.Master, S.Stratigraphy, tectonic setting and mineralization of the early Proterozoic Magondi Supergroup, Zimbabwe: a reviewEconomic Geology Research Unit, Information Circular No. 238, 75pZimbabweProterozoic, Magondi Supergroup
DS1995-1176
1995
Master, S.Master, S.Meteorite impact structures in ZimbabweCentennial Geocongress (1995) Extended abstracts, Vol. 1, p. 574-576. abstractZimbabweMeteorite, Impact structure
DS1996-0900
1996
Master, S.Master, S.Excursion guidebook: Paleoproterozoic of Zambia and ZimbabweEgru, No. 302, 61pZambia, ZimbabweBook - table of contents, Domes area, Magondi Mobile belt
DS2000-0627
2000
Master, S.Master, S.Bibliography of the geology and mineral resources of Liberia and Sierra Leone and the adjacent Archean terrains of Guinea and Cote d'Ivoire, West Africa.Economic Geology Research Institute, EGRU Wits, Information Circular, No. 342, 67p.Liberia, Sierra Leone, Guinea, Ivory CoastBibliography
DS1991-1889
1991
Masters, G.Woodward, R.L., Masters, G.Lower mantle structure from ScS-S differential travel timesNature, Vol. 352, No. 6332, July 18, pp. 231-234GlobalMantle, Geophysics
DS2001-1036
2001
Masters, G.Schulte-Pelkum, V., Masters, G., Shearer, P.M.Upper mantle anisotropy from long period P polarizationJournal of Geophysical Research, Vol. 106, No. 10, pp.21,917-34.MantleGeophysics - seismics
DS2002-0809
2002
Masters, G.Karato, S., Forte, A.M.,Liebermann, R.C., Masters, G., Stixrude, L.Earth's deep interior: mineral physics and tomography from the atomic to the global scale.American Geophysical Union, Geophysical Monograph Series, 117,289p., 289p.MantleBook - geodynamics, seismic tomography, core, boundary, Discontinuities, mantle minerals, mantle structure
DS200412-0741
2004
Masters, G.Gubbins, D., Alfe, D., Masters, G., Price, G.D., Gillan, M.Gross thermodynamics of two component core convection.Geophysical Journal International, Vol. 157, 3, pp. 1407-1414.MantleConvection
DS200412-1355
2004
Masters, G.Montelli, R., Nolet, G., Dahlen, F.A., Masters, G., Engdahl, E.R., Hung, S.H.Finite frequency tomography reveals a variety of plumes in the mantle.Science, No. 5656 Jan. 16, pp. 338-42.MantleGeophysics - seismics
DS200512-0947
2004
Masters, G.Schubert, G., Masters, G., Olson, P., Tackley, P.Superplumes or plume clusters?Physics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 147-178.MantlePlume
DS200612-0774
2006
Masters, G.Lawrence, J.F., Shearer, P.M., Masters, G.Mapping attenuation beneath North America using waveform cross correlation and cluster analysis.Geophysical Research Letters, Vol. 33, 7, April 16, L07315Canada, United StatesGeophysics - seismics
DS200712-0744
2006
Masters, G.Montelli, R., Nolet, G., Dahlen, F.A., Masters, G.A catalogue of deep mantle plumes: new results from finite-frequency tomography.Geochemical, Geophysics, Geosystems: G3, Vol. 7 Q11007Global, mantleGeophysics - seismics, Frechet derivatives
DS200812-0435
2008
Masters, G.Gubbins, D., Masters, G., Nimmo, F.A thermochemical boundary layer at the base of Earth's outer core and independent estimate of core heat flux.Geophysical Journal International, Vol. 174, 3m pp. 1007-1018.MantleGeothermometry
DS1989-0953
1989
Masters, T.G.Masters, T.G.Low frequency seismology and the three dimensional structure of theearthPhil. Transactions Royal Soc. London, Vol. 328, No. 1599, July 4, pp. 329-335GlobalGeophysics, Seismics
DS1991-1074
1991
Masters, T.G.Masters, T.G.Structure of the Earth -mantle and coreReviews of Geophysics, Vol. 29, pt. 2, pp. 671-679. supplement SeismologyGlobalMantle, Geophysics -seismics
DS1992-1380
1992
Masters, T.G.Shearer, P.M., Masters, T.G.Global mapping of topography on the 660 km discontinuityNature, Vol. 355, No. 6363, February 27, pp. 791-795MantleMantle Discontinuity, Subduction zones, Geophysics
DS1993-0979
1993
Masters, T.G.Masters, T.G.Core models ring true.. inner coreNature, Vol. 366, December 16, pp. 629-630MantleCore, Geophysics -seismics
DS201704-0652
2017
Masters, T-G.Walpole, J., Wookey, J., Kendall, J-M., Masters, T-G.Seismic anisotropy and mantle flow below subducting slabs.Earth and Planetary Science Letters, Vol. 465, pp. 155-167.MantleSubduction

Abstract: Subduction is integral to mantle convection and plate tectonics, yet the role of the subslab mantle in this process is poorly understood. Some propose that decoupling from the slab permits widespread trench parallel flow in the subslab mantle, although the geodynamical feasibility of this has been questioned. Here, we use the source-side shear wave splitting technique to probe anisotropy beneath subducting slabs, enabling us to test petrofabric models and constrain the geometry of mantle fow. Our global dataset contains 6369 high quality measurements - spanning ?40,000?km?40,000?km of subduction zone trenches - over the complete range of available source depths (4 to 687?km) - and a large range of angles in the slab reference frame. We find that anisotropy in the subslab mantle is well characterised by tilted transverse isotropy with a slow-symmetry-axis pointing normal to the plane of the slab. This appears incompatible with purely trench-parallel flow models. On the other hand it is compatible with the idea that the asthenosphere is tilted and entrained during subduction. Trench parallel measurements are most commonly associated with shallow events (source depth <50?km<50?km) - suggesting a separate region of anisotropy in the lithospheric slab. This may correspond to the shape preferred orientation of cracks, fractures, and faults opened by slab bending. Meanwhile the deepest events probe the upper lower mantle where splitting is found to be consistent with deformed bridgmanite.
DS200912-0099
2009
Masterson, A.Cartigny, P., Farquar, J., Thomassot, E., Harris, J.W., Wing, B., Masterson, A., McKeegan, K., Stachel, T.A mantle origin for Paleoarchean peridotite diamonds from the PAnd a kimberlite, Slave Province: evidence from 13C, 15N and 34,34S stable isotope systematics.Lithos, In press - available 38p.Canada, Northwest TerritoriesDeposit - Panda
DS1982-0408
1982
Masterson, G.Masterson, G.SolitairePretoria: Africana Booksellers, 568P.South AfricaKimberley, Fiction
DS1983-0435
1983
Masterson, M.Masterson, M.Town Finds Gem in Diamond MineUsa Today, APRIL 6TH, WEDNESDAY, P. 3A.United States, Gulf Coast, Arkansas, PennsylvaniaNews Item. Diamond Notable
DS1910-0204
1911
Mastin, J.Mastin, J.The Chemistry, Properties and Tests of Precious StonesLondon: E.f.n. Spon Ltd., 114P.GlobalKimberley, Diamonds
DS1910-0205
1911
Mastin, J.Mastin, J.The Ancient Mining of Gold, Silver and Precious StonesLondon: E.f.n. Spon Ltd., 50P.GlobalKimberlite
DS1991-1075
1991
Mastyulin, L.A.Mastyulin, L.A., Kuznetsov, Y.N., Astapenk..., V.N.The prospects of the Kaunas Polotsk zone of plutonic ruptures for kimberlite pipes in the light of plutonic geophysics.(Russian)Doklady Academy of Sciences Nauk. BSSR, (Russian), Vol. 35, No. 12, December pp. 1123-1126RussiaGeophysics, Structure
DS1988-0004
1988
Masuda, A.Akagi, T., Masuda, A.Isotopic and elemental evidence for a relationship between kimberlite and Zaire cubic diamondsNature, Vol. 336, No. 6200, Dec. 15, pp. 665-667Democratic Republic of CongoDiamond morphology
DS1988-0444
1988
Masuda, A.Masuda, A., Akagi, T.The cause of misleading K-Ar ages of diamonds, actually young but apparently older than the solar systemGeochemical Journal, Vol. 22, pp. 139-142GlobalAge determinations, Experimental
DS1990-0794
1990
Masuda, A.Kagi, H., Takahashi, K., Masuda, A.Laser-induced luminescence from micro-diamonds of urelliteNatur-wissenschaften, Vol. 77, No. 11, November pp. 531-532GlobalMicrodiamonds, Lumininesence
DS1990-1350
1990
Masuda, A.Shimizu, H., Umemoto, N., Masuda, A., Appel, P.W.U.Sources of iron formations in the Archean Isua and Malene supracrustalsGeochimica et Cosmochimica Acta, Vol. 54, No. 4, April pp. 1147-1154GreenlandIron formations, Geochronology
DS1991-0818
1991
Masuda, A.Kagi, H., Masuda, A.Laser induced luminescence from natural polycrystal diamond, carbonado- A new possible thermal indicator of meteoritic diamondsNaturwissenschaften, Vol. 78, No. 8, August pp. 355-358GlobalCarbonado, Geothermometry - luminescenece
DS1991-0819
1991
Masuda, A.Kagi, H., Takahashi, K., Masuda, A.Raman-scattering and laser induced luminesence from micro-diamonds inurelitesMeteoritics, Vol. 26, No. 4, December p. 354GlobalUrelites, Micro-diamonds
DS1994-0335
1994
Masuda, A.Cong-Qiang Liu, Masuda, A., Guang Hong XiMajor and trace element compositions of Cenozoic basalts in China:petrogenesis and mantle source.Chemical Geology, Vol. 114, pp. 19-42.ChinaXenoliths, Mineral chemistry
DS1995-0043
1995
Masuda, K.Anderson, O.L., Masuda, K., Guo, D.Pure silicate perovskite and the PREM lower mantle model: a thermodynamicanalysis.Physics of the Earth and Plan. Interiors, Vol. 89, pp. 35-49.MantlePerovskite
DS201908-1791
2019
Masuda, K.Masuda, K., Arai, T., Takahashi, M.Effects of frictional properties of quartz and feldspar in the crust on the depth extent of the seismogenic zone. ** not specific to diamondProgress in Earth and Planetary Science, doi.org/10.1186 /s40645-019-0299-5Mantlegeophysics - seismic

Abstract: The depth extent of the crustal seismogenic zone is closely related to the size of earthquakes. The mechanisms that control the depth of the lower transition of the seismogenic zone are important issues in seismology and disaster mitigation. Laboratory studies have shown that the mechanism of earthquake nucleation is controlled by the frictional properties of fault materials. We measured the velocity dependences of the steady-state friction of quartz and feldspar, two major components of crustal rocks, under dry and wet conditions at temperatures up to 600?°C. In the presence of water, the temperature range over which the velocity dependence of steady-state friction was negative was wider for feldspar than for quartz, thus indicating that the temperature range of earthquake nucleation is wider for feldspar than for quartz. Considering that temperature increases with depth, our findings indicate that the material properties of feldspar likely play a dominant role in limiting the depth extent of the seismogenic zone.
DS1993-1275
1993
Masumoto, S.Raghaven, V., Wadatsumi, K., Masumoto, S.Automatic extraction of lineament information from satellite images using digital eleveation dataNonrenewable Resources, Vol. 2, No. 2, Summer pp. 148-155JapanRemote sensing, Tectonics, structure
DS1993-1369
1993
Masumoto, S.Sakamoto, M., Shiono, K., Masumoto, S., Wadatsumi, K.A computerized geologic mapping system based on logical models of geologicstructuresNonrenewable Resources, Vol. 2, No. 2, Summer pp. 140-147GlobalComputer, Program -CIGMA.
DS200612-0873
2006
Masun, K.Masun, K., Scott Smith, B.The Pimenta Bueno kimberlite field, Rondonia, Brazil: evidence for tuffisitic kimberlite.Emplacement Workshop held September, 5p. extended abstractSouth America, Brazil, RondoniaDeposit - Pimenta Bueno - petrography
DS200912-0478
2009
Masun, K.Masun, K., Sthapak, A.V., Singh, A., Vaidya, A., Krishna, C.Exploration history and geology of the Diamondiferous ultramafic Saptarshi intrusions, Madhya Pradesh, India.Lithos, In press available, 37p.IndiaBunder project area
DS201112-0651
1999
Masun, K.Masun, K.Kimberlites from the Lac de Gras region.Thesis: Msc. Lakehead University, Canada, Northwest TerritoriesThesis - note availability based on request to author
DS2002-1007
2002
Masun, K.M.Masun, K.M.Lac de Gras kimberlites, Slave Craton, NWTGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.74., p.74.Northwest TerritoriesPwtrology
DS2002-1008
2002
Masun, K.M.Masun, K.M.Lac de Gras kimberlites, Slave Craton, NWTGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.74., p.74.Northwest TerritoriesPwtrology
DS2003-0890
2003
Masun, K.M.Masun, K.M., Doyle, B.J., Ball, S., Walker, S.The geology and mineralogy of the Anuri kimberlite, Nunavut, Canada31st Yellowknife Geoscience Forum, p. 63. (abst.)NunavutMineralogy
DS2003-0891
2003
Masun, K.M.Masun, K.M., Doyle, B.J., Ball, S.A., Walker, S.The geology and mineralogy of the Anuri kimberlite, Nunavut, Canada8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractNunavutKimberlite geology and economics, Deposit - Anuri
DS200412-1244
2003
Masun, K.M.Masun, K.M., Doyle, B.J., Ball, S., Walker, S.The geology and mineralogy of the Anuri kimberlite, Nunavut, Canada.31st Yellowknife Geoscience Forum, p. 63. (abst.Canada, NunavutMineralogy
DS200812-0720
2008
Masun, K.M.Masun, K.M., Scott Smith, B.H.The Pimenta Bueno kimberlite field, Rondonia, Brazil: tuffisitic kimberlite and transitional textures.Journal of Volcanology and Geothermal Research, Vol. 174, 1-3, pp. 81-89.South America, Brazil, RondoniaDiatreme,emplacement, transitional textures
DS1993-0868
1993
MasuokaKusky, T.M., Lowman, Masuoka, BlodgetAnalysis of Seasat L Band Radar imagery of the West Bay Indin Lake faultsystemJournal of Geology, Vol. 101, pp. 623-32.Northwest TerritoriesRemote Sensing, Slave Province
DS1993-0869
1993
Masuoka, P.Kusky, T.M., Lowman, P.D.Jr., Masuoka, P., Blodget, H.W.Analysis of Seasat L-Band radar imagery of the West Bay-Indin Lake FaultSystem, Northwest TerritoriesJournal of Geology, Vol. 101, No. 5, September pp. 623-632Northwest TerritoriesRemote Sensing
DS202004-0499
2020
Masuyeau, M.Aulbach, S., Masuyeau, M., Gerdes, A., Garber, J.M.Ultramafic carbonated melt- and-auto -metasomatism in mantle eclogites: compositional effects and geophysical consequences.Geochemistry, Geophysics, Geosystems, in press available, 41p. PdfMantleeclogites
DS200812-1286
2008
Masuzawa, T.Yamaguchi, H.,Kudo, Y., Masuzawa, T., Kudo, M., Yamada, Takakuwa, OkanoCombine x-ray photoelectron spectroscopy/ultraviolet photoelectron spectroscopy/field emission spectroscopy for characterization of electron emmision of diamond.Journal of Vacuum Science and Technology B Microelectronics and Nanometer Structures, Vol. 26, 2, pp. 730-734. American Vacuum SocietyTechnologyDiamond emission
DS200812-1287
2008
Masuzawa, T.Yamaguchi, H., Salto, I., Kudi, Y., Masuzawa, T., Yamada, T., Kudo, M., Takakuma, Y., Okano, K.Electron emission mechanism of hydrogeneated natural type IIb diamond (111).Diamond and Related Materials, Vol. 17, 2, pp. 162-166.TechnologyType II diamonds
DS201112-0652
2011
Masy, J.Masy, J., Niu, F., Levander, A., Schmitz, M.Mantle flow beneath northwestern Venezuela: seismic evidence for a deep origin of the Merida Andes.Earth and Planetary Science Letters, Vol. 305, 3-4, pp. 396-404.South America, VenezuelaGeophysics - seismics
DS201112-0653
2011
Masy, J.Masy, J., Niu, F., Levander, A., Schmitz, M.Mantle flow beneath northwestern Venezuela: seismic evidence for a deep orogin of the Merida Andes.Earth and Planetary Science Letters, In press, availableSouth America, VenezuelaGeophysics - seismics
DS201501-0019
2015
Masy, J.Masy, J., Niu, F., Levander, A., Schmitz, M.Lithospheric expression of cenozoic subduction, mesozoic rifting and the Precambrian shield in Venezuela.Earth and Planetary Science Letters, Vol. 410, pp. 12-24.South America, VenezuelaSubduction
DS1998-0959
1998
Mata, J.Mata, J.Earth mantle geochemical evolution: a diachronic fractionation model for Ulead and Th U ratios.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 965-6.MantleGeochemistry, Mid Ocean Ridge Basalt (MORB), Ocean Island Basalt (OIB).
DS200712-0272
2007
Mata, J.Doucelance, R., Mata, J., Moreira, M., Silva, L.C.Isotope evidence for the origin of Cape Verde oceanic carbonatites.Plates, Plumes, and Paradigms, 1p. abstract p. A233.Europe, Cape Verde IslandsCarbonatite, geochronology
DS201012-0475
2010
Mata, J.Mata, J., Moreira, M., Doucelance, R., Ader, M., Silva, L.C.Noble gas and carbon isotopic signatures of Cape Verde oceanic carbonatites: implications for carbon provenance.Earth and Planetary Science Letters, Vol. 291, 1-4, pp. 70-83.Europe, Cape Verde IslandsCarbonatite
DS201012-0519
2009
Mata, J.Mourai, C., Mata, J., Doucelance, R., Madeira, J., Brum da Silviera, A., Silva, L.C., Moreira, M.Quaternary extrusive calciocarbonatite volcanism on Brava Island ( Cape Verde): a nephelinite carbonatite immiscibility product.Journal of African Earth Sciences, Vol. 56, 2-3, pp. 59-74.Europe, Cape Verde IslandsCarbonatite
DS201212-0497
2012
Mata, J.Mourao, C., Mata, J., Doucekance, R., Madeira, J., Millet, M-A., Moreira, M.Geochemical temporal evolution of Brava Island magmatism: constraints on the variability of Cape Verde mantle sources and on carbonatite-silicate magma link.Chemical Geology, Vol. 334, pp. 44-61.Europe, Cape Verde IslandsCarbonatite
DS201212-0498
2012
Mata, J.Mourao, C., Moreira, M., Mata, J., Raquin, A., Madeira, J.Primary and secondary processes constraining the noble gas isotopic signatures of carbonatites and silicate rocks from Brava Island: evidence for a lower mantle origin of the Cape Verde Plume.Contributions to Mineralogy and Petrology, Vol. 163, 6, pp. 995-1009.Europe, Brava IslandCarbonatite
DS201805-0952
2017
Mata, J.Ikenne, M., Lahna, A.A., Soderlund, U., Tassinar, C.C.G., Ernst, R.E., Pin, Ch., Youbi, N., El Aouli, EH., Hafid, A., Admou, H., Mata, J., Bouougri, EH., Boumehdi, M.A.New Mesoproterozoic age constraints for the Taghdout Group, Anti-Atlas ( Morocco): toward a new lithostratigra[hic framework for the Precambrian in the NW margin of the West African Craton.The First West African Craton and Margins International Workshop WACMA, Held Apr. 24-29. 1p. AbstractAfrica, Moroccogeochronology
DS202007-1122
2020
Mata, J.Amsellem, E., Moynier, F., Betrand, H., Bouyon, A., Mata, J., Tappe, S., Day, J.M.D.Calcium isotopic evidence for the mantle source of carbonatites.Science Adavances, Vol. 6, 63 eaba3269 6p. PdfMantlecarbonatite

Abstract: The origin of carbonatites—igneous rocks with more than 50% of carbonate minerals—and whether they originate from a primary mantle source or from recycling of surface materials are still debated. Calcium isotopes have the potential to resolve the origin of carbonatites, since marine carbonates are enriched in the lighter isotopes of Ca compared to the mantle. Here, we report the Ca isotopic compositions for 74 carbonatites and associated silicate rocks from continental and oceanic settings, spanning from 3 billion years ago to the present day, together with O and C isotopic ratios for 37 samples. Calcium-, Mg-, and Fe-rich carbonatites have isotopically lighter Ca than mantle-derived rocks such as basalts and fall within the range of isotopically light Ca from ancient marine carbonates. This signature reflects the composition of the source, which is isotopically light and is consistent with recycling of surface carbonate materials into the mantle.
DS202009-1605
2020
Mata, J.Amsellem, E., Moynier, F., Bertrand, H., Bouyon, A., Mata, J., Tappe, S., Day, J.M.D.Calcium isotopic evidence for the mantle sources of carbonatites. ( Oldoinyo Lengai)Science Advances, Vol. 6, eaba3269 June 3, 7p. PdfGlobal, Africa, Tanzaniacarbonatites

Abstract: The origin of carbonatites-igneous rocks with more than 50% of carbonate minerals-and whether they originate from a primary mantle source or from recycling of surface materials are still debated. Calcium isotopes have the potential to resolve the origin of carbonatites, since marine carbonates are enriched in the lighter isotopes of Ca compared to the mantle. Here, we report the Ca isotopic compositions for 74 carbonatites and associated silicate rocks from continental and oceanic settings, spanning from 3 billion years ago to the present day, together with O and C isotopic ratios for 37 samples. Calcium-, Mg-, and Fe-rich carbonatites have isotopically lighter Ca than mantle-derived rocks such as basalts and fall within the range of isotopically light Ca from ancient marine carbonates. This signature reflects the composition of the source, which is isotopically light and is consistent with recycling of surface carbonate materials into the mantle.
DS202111-1758
2020
Mata, J.Boutyon, A., Klausen, M., Mata, J., Tappe, S., Farquhar, J., Cartigny, P.Multiple sulfur isotopes of carbonatites, a window into their formation conditions.Goldschmidt2020, 1p. Abstract pdfMantlecarbonatite

Abstract: Carbonatites are rare volcanic rocks whose carbon/oxygen isotope signatures point towards a mantle origin. However there is still debate on the role of processes such as partial melting or the recycling of sediments for their generation. Carbonatite quadruple sulfur isotope measurements should be useful for deciphering the imprints of Earth’s earliest atmosphere and microbial cycling, two processes isotopically characterized by different slopes in a ?33S-?36S diagram, and thus help to better understand the origin of carbonatites, and the possiblity of sedimentary precursors, in greater detail. We report here multiple sulfur data for a wide range of carbonatite samples: 4 continents, from today to 3Ga, oceanic and continental settings. 80 measurements from 18 localities yielded sulfur in sulfides between 0 to 1wt%, with ?34S ranging from -20‰ to +10‰. The record through time seems to correlate with the sedimentary record albeit with some delay. ?33S varies between -0.1 to 0.4‰. Most of the samples display unequivocal mass-dependent fractionation, characteristic of the sedimentary record. A few samples show mass-independent fractionation. ?33S shows a temporal variation from near zero at 3Ga to positive values until 500Ma and then a broadening with both positive and negative values. This is interpreted to reflect the assimilation of surface derived sulfur in the source of carbonatites. The mixing with mantle sulfur narrows the amplitude of the variation and a crustal imprint could blur the signal as well. However coupled ?34S-?33S point toward two different stages in the sulfur isotopic signature: a long recycling before 900Ma and a much shorter residence time, on the order of 300 Myrs, after. This could be linked with a preferential recycling of sulfides in the early time and a recycling of both sulfides and sulfates later on.
DS201605-0869
2016
Matabane, M.Matabane, M., Khati, T.Application of gamma ray logging for kimberlite contact delineation at Finsch diamond mine.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 87-104.Africa, South AfricaDeposit - Finsch
DS201807-1503
2018
Matabane, M.Khati, T., Matabane, M.Kimberlite country rock contact delineation at Finsch diamond mine. Mining applications and developmentSAIMM Diamonds - source to use 2018 Conference 'thriving in changing times'. June 11-13., pp. 9-22.Africa, South Africadeposit - Finsch
DS201910-2273
2019
Matabane, M.Khati, T., Matabane, M.kimberlite country rock contact delineation at Finsch diamond mine.The Journal of the Southern African Institute of Mining and Metallurgy, Vol. 119, pp. 97-103.Africa, South Africadeposit - Finsch

Abstract: Accurate delineation of the contact between a kimberlite pipe and country rock at production level depths is a challenge due to limited geological data. Geological information is obtained from widely spaced diamond core boreholes which are drilled either from surface or from higher mining levels within the pipe. Kimberlite pipe/country rock contacts are notoriously irregular and variable, further reducing the confidence in contact positions defined by the drill-holes. At Finsch Diamond Mine (FDM), the opportunity arose to further improve the confidence in the contact positions relative to the planned slot (end) positions of each sublevel cave tunnel during the development stage of these tunnels. As a result, the accuracy of the 3D geological model has improved. The use of diamond drill core for this purpose is expensive due to site establishment requirements. The lengthy time taken during site establishment also delays the development of tunnels and support cycles, thereby extending the completion dates. FDM has reduced delays during development by adopting percussion drilling, in conjunction with gamma ray logging. The S36 drill rig is mounted on a moveable platform and does not require a costly and lengthy site establishment. The holes are generally drilled (0°/flat) on grade elevation, and these holes could also be drilled from the rim tunnels (developed in waste) into the kimberlite pipe. A single-boom production drill rig is normally used to drill holes about 20 m in length. On completion of the contact delineation drilling, gamma logging of the holes is conducted using the GeoVista geophysical sonde (or probe) to log the natural gamma signature of the dolomite/ kimberlite contact. The advantage of this tool is that the readings are continuous within centimetre intervals, and due to contrasting characteristics between kimberlite (rich in clay minerals) and dolomite, the contact position can be determined accurately. The better definition of contact positions also adds value to tunnel stopping distance in terms of developing the tunnel's slot at the optimum distance from the contact (easier blasting of longhole rings, avoidance of contact overbreak and premature waste ingress, and other matters relating to extraction of ore from these tunnels). This method is highly successful and has reduced development costs (on-time completion), improved definition of the pipe's contact position for geological modelling, improved blast design, and mitigated early waste ingress by maintaining the contact's integrity.
DS2002-1009
2002
Mataragio, J.P.Mataragio, J.P., Ohde, S., Hogan, J.P.Geochemistry of PAnd a Hill carbonatites from Tanzania: implications for their origin and evolution.16th. International Conference On Basement Tectonics '02, Abstracts, 2p., 2p.TanzaniaGeochronology
DS1998-0512
1998
MatasGillet, Ph., Matas, Fiquet, Chamorro, Maryinez, JambonVolatiles in the Earth's mantle: insights from mineral and melt physicsMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 521-2.MantleMagnesite, noble gases, volcanism.
DS2000-0628
2000
Matas, J.Matas, J., Ricard, Y., Guyot, F.An improved thermodynamic model of metal olivine pyroxene stability domainsContributions to Mineralogy and Petrology, Vol. 140, No. 1, pp. 73-83.GlobalMineral chemistry - olivine-pyroxene
DS2001-0148
2001
Matas, J.Bunge, H-P., Ricard, Y., Matas, J.Non-adiabaticity in mantle convectionGeophysical Research Letters, Vol. 28, No. 5, Mar. 1, pp. 879-82.MantleGeophysics - seismics
DS200512-0693
2005
Matas, J.Mattern, E., Matas, J., Ricard, Y.,Bass, J.Lower mantle composition and temperature from mineral physics and thermodynamic modelling.Geophysical Journal International, Vol. 160, 3, pp. 973-990.MantleGeothermometry
DS200512-0694
2005
Matas, J.Mattern, E., Matas, J., Ricard, Y., Bass, J.Lower mantle composition and temperature from mineral physics and thermodynamic modelling.Geophysical Journal International, Vol. 160, 3, pp. 973-990.MantleGeothermometry
DS200612-0096
2006
Matas, J.Bass, J., Matas, J.Mineral elasticity: implications for the temperature and mineralogy of the lower mantle.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p. 127.MantleMineral phases
DS200612-0097
2006
Matas, J.Bass, J.D., Sanchez-Valle, C., Lakshtanov, D.L., Brenizer, J., Wang, J., Matas, J.Elastic properties of high pressure phases and implications for the temperature and mineralogy of Earth's lower mantle.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.MantleGeothermometry
DS200612-1158
2005
Matas, J.Ricard, Y., Mattern, E., Matas, J.Synthetic tomographic images of slabs from mineral physics.American Geophysical Union, Geophysical Monograph, ed. Van der Hilst, Earth's Deep mantle, structure ...., No. 160, pp. 283-200.MantleTomography, subduction
DS200612-1462
2005
Matas, J.Van der Hilst, R.D., Bass, J.D., Matas, J., Trampert, J.Earth's deep mantle structure, composition, and evolution - an introduction.American Geophysical Union, Geophysical Monograph, Ed. Van der Hilst, Earth's Deep Mantle, structure ...., No. 160, pp. 1-8.MantleTectonics
DS200712-0694
2007
Matas, J.Matas, J., Bass, J., Ricard, Y., Mattern, E., Bukowinski, M.S.T.On the bulk composition of the lower mantle: predictions and limitations from generalized inversion seismic profiles.Geophysical Journal International, Vol. 170, 2, August pp. 764-780.MantleGeophysics - seismics
DS200712-0695
2007
Matas, J.Matas, J., Bukowinski, M.S.On the An elastic contribution to the temperature dependence of lower mantle seismic veolcities.Earth and Planetary Science Letters, Vol. 259, 1-2, pp. 51-65.MantleGeophysics - seismics
DS200712-0696
2007
Matas, J.Matas, J., Bukowinski, M.S.On the An elastic contribution to the temperature dependence of lower mantle seismic veolcities.Earth and Planetary Science Letters, Vol. 259, 1-2, pp. 51-65.MantleGeophysics - seismics
DS201212-0172
2012
Matas, J.Durand, S., Chambat, F., Matas, J., Ricard, Y.Constraining the kinetics of mantle phase changes with seismic data.Geophysical Journal International, in press availableMantleGeophysics - seismics
DS201704-0642
2017
Matat Jabion, B.Navon, O., Wirth, R., Schmidt, C., Matat Jabion, B., Schreiber, A., Emmanuel, S.Solid molecular nitrogen ( delta -N2) inclusions in Juin a diamonds: exsolution at the base of the transition zone.Earth and Planetary Science Letters, Vol. 464, pp. 237-247.South America, BrazilDeposit - Juina
DS200812-0721
2008
Matchan, E.Matchan, E.The age, geochemistry and petrogenesis of an unusual alkaline intrusion in the western Pilbara Craton, western Australia.9IKC.com, 3p. extended abstractAustralia, Western AustraliaYanyare dykes
DS200912-0479
2009
Matchan, E.Matchan, E., Hergt, J., Phillips, D., Shee, S.The geochemistry, petrogenesis and age of an unusual alkaline intrusion in the western Pilbara craton, western Australia.Lithos, In press availableAustraliaGeochronology
DS200912-0480
2008
Matchan, E.Matchan, E., Hergt, J., Phillips, D., Shee, S.The age, geochemistry and petrogenesis of an unusual alkaline intrusion in the western Pilbara, western Australia.Geological Society of Australia Abstracts, Vol. 90, p. 36. abs.AustraliaAlkalic
DS201810-2366
2018
Matchan, E.Phillips, D., Harris, J.W., de Wit, M.C.J., Matchan, E.Provenance history of detrital diamond deposits, West Coast of Namaqualand, South Africa.Mineralogy and Petrology, doi:10.1007/ s00710-018-0568-9 15p.Africa, South Africadeposit - Group I, orangeites Group II

Abstract: The West Coast of Namaqualand in South Africa hosts extensive detrital diamond deposits, but considerable debate exists as to the provenance of these diamonds. Some researchers have suggested derivation of the diamonds from Cretaceous-Jurassic kimberlites (also termed Group I kimberlites) and orangeites (also termed Group II kimberlites) located on the Kaapvaal Craton. However, others favour erosion of diamonds from the ca.300 Ma Dwyka Group sediments, with older, pre-Karoo kimberlites being the original source(s). Previous work has demonstrated that 40Ar/39Ar analyses of clinopyroxene inclusions, extracted from diamonds, yield ages approaching the time(s) of source kimberlite emplacement, which can be used to constrain the provenance of placer diamond deposits. In the current study, 40Ar/39Ar analyses were conducted on clinopyroxene inclusions from two similar batches of Namaqualand detrital diamonds, yielding (maximum) ages ranging from 117.5?±?43.6 Ma to 3684?±?191 Ma (2s) and 120.6?±?15.4 Ma to 688.8?±?4.9 Ma (2s), respectively. The vast majority of inclusions (88%) produced ages younger than 500 Ma, indicating that most Namaqualand diamonds originated from Cretaceous-Jurassic kimberlites/orangeites, with few, if any, derived from the Dwyka tillites. The provenance of the Namaqualand diamonds from ca.115-200 Ma orangeites is consistent with Late Cretaceous paleo-drainage reconstructions, as these localities could have been sampled by the ‘paleo-Karoo’ River and transported to the West Coast via an outlet close to the current Olifants River mouth. At ca.90 Ma, this drainage system appears to have been captured by the ‘paleo-Kalahari’ River, a precursor to the modern Orange River system. This latter drainage is considered to have transported diamonds eroded from both ca.80-90 Ma kimberlites and ca.115-200 Ma orangeites to the West Coast, which were subsequently reworked along the Namibian coast, forming additional placer deposits.
DS202008-1383
2020
Matchan, E.Dalton, H., Giuiani, A., Phillips, D., Hergt, J., Maas, R., Woodhead, J., Matchan, E., O'Brien, H.Kimberlite magmatism in Finland: distinct sources and links to the breakup of Rodinia.Goldschmidt 2020, 1p. AbstractEurope, Finlanddeposit - Kuusamo

Abstract: The Karelian Craton in Finland is host to (at least) two distinct pulses of kimberlite magmatism. Twenty kimberlite occurrences have so far been discovered on the southwest margin of the craton at Kaavi-Kuopio and seven kimberlites are located in the Kuusamo area within the core of the craton. Comprehensive radiometric age determinations (U-Pb, Ar- Ar and Rb-Sr) reveal that all kimberlite activity was restricted to the Proterozoic. The Kaavi-Kuopio field was emplaced over a protracted period from ~610 to 550 Ma and is predated by the Kuusamo cluster that represents a relatively short pulse of magmatism at ~750 to 730 Ma. The emplacement of kimberlites globally has recently been linked to supercontinent reorganisation and we propose a similar scenario for these Finnish occurrences which, at the time of kimberlite emplacement, were situated on the Baltica paleo-continent. This land mass was contiguous with Laurentia in the Proterozoic and together formed part of Rodinia. The breakup of Rodinia is considered to have commenced at ~750 Ma and initiation of the opening of the Iapetus ocean at ~615 Ma. Contemporaneous with Kaavi-Kuopio magmatism, this latter period of Neoproterozoic crustal extension also includes the emplacement of kimberlites and related rocks in areas that were linked with Baltica as part of Rodinia - West Greenland and eastern North America. Both the initial and final periods of Rodinia’s breakup have been linked to mantle upwellings from the core-mantle boundary. We suggest that kimberlite magmatism in Finland was promoted by the influx of heat from mantle upwellings and lithospheric extension associated with the demise of Rodinia. Although both magmatic episodes are potentially linked to the breakup of Rodinia, whole-rock and perovskite radiogenic isotope compositions for the Kuusamo kimberlites (?Nd(i) +2.6 to +3.3, ?Hf(i) +3.1 to +5.6) are distinct from the Kaavi-Kuopio kimberlites (?Nd(i) -0.7 to +1.8, ?Hf(i) -6.1 to +5.2). The spread in Hf isotope compositions for the Kaavi-Kuopio magmas may be linked to variable assimilation of diverse mantle lithologies.
DS201807-1523
2018
Matchan, E.L.Phillips, D., Harris, J.W., de Wit, M.C.J., Matchan, E.L.Provenance history of detrital diamond deposits, West Coast of Namaqualand, South Africa.Mineralogy and Petrology, 10.1007/ s00710-018- 0568-9, 15p.Africa, South Africageochronology

Abstract: The West Coast of Namaqualand in South Africa hosts extensive detrital diamond deposits, but considerable debate exists as to the provenance of these diamonds. Some researchers have suggested derivation of the diamonds from Cretaceous-Jurassic kimberlites (also termed Group I kimberlites) and orangeites (also termed Group II kimberlites) located on the Kaapvaal Craton. However, others favour erosion of diamonds from the ca.300 Ma Dwyka Group sediments, with older, pre-Karoo kimberlites being the original source(s). Previous work has demonstrated that 40Ar/39Ar analyses of clinopyroxene inclusions, extracted from diamonds, yield ages approaching the time(s) of source kimberlite emplacement, which can be used to constrain the provenance of placer diamond deposits. In the current study, 40Ar/39Ar analyses were conducted on clinopyroxene inclusions from two similar batches of Namaqualand detrital diamonds, yielding (maximum) ages ranging from 117.5?±?43.6 Ma to 3684?±?191 Ma (2?) and 120.6?±?15.4 Ma to 688.8?±?4.9 Ma (2?), respectively. The vast majority of inclusions (88%) produced ages younger than 500 Ma, indicating that most Namaqualand diamonds originated from Cretaceous-Jurassic kimberlites/orangeites, with few, if any, derived from the Dwyka tillites. The provenance of the Namaqualand diamonds from ca.115-200 Ma orangeites is consistent with Late Cretaceous paleo-drainage reconstructions, as these localities could have been sampled by the ‘paleo-Karoo’ River and transported to the West Coast via an outlet close to the current Olifants River mouth. At ca.90 Ma, this drainage system appears to have been captured by the ‘paleo-Kalahari’ River, a precursor to the modern Orange River system. This latter drainage is considered to have transported diamonds eroded from both ca.80-90 Ma kimberlites and ca.115-200 Ma orangeites to the West Coast, which were subsequently reworked along the Namibian coast, forming additional placer deposits.
DS201812-2851
2018
Matchan, E.L.Moss, S., Marten, B.E., Felgate, M., Smith, C.B., Chimuka, L., Matchan, E.L., Phillips, D.Murowa deposit: Geology, structure and radiometric age determination of the Murowa kimberlites, Zimbabwe.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 379-402.Africa, Zimbabwedeposit - Murowa
DS201801-0017
2017
Matchen, E.L.Giuliani, A., Campeny, M., Kamenetsky, V.S., Afonso, J.C., Maas, R., Melgarejo, J.C., Kohn, B.P., Matchen, E.L., Mangas, J., Goncalves, A.O., Manuel, J.Southwestern Africa on the burner: Pleistocene carbonatite volcanism linked to deep mantle upwelling in Angola.Geology, Vol. 45, 11, pp. 971=974.Africa, Angolacarbonatite - Catanda

Abstract: The origin of intraplate carbonatitic to alkaline volcanism in Africa is controversial. A tectonic control, i.e., decompression melting associated with far-field stress, is suggested by correlation with lithospheric sutures, repeated magmatic cycles in the same areas over several million years, synchronicity across the plate, and lack of clear age progression patterns. Conversely, a dominant role for mantle convection is supported by the coincidence of Cenozoic volcanism with regions of lithospheric uplift, positive free-air gravity anomalies, and slow seismic velocities. To improve constraints on the genesis of African volcanism, here we report the first radiometric and isotopic results for the Catanda complex, which hosts the only extrusive carbonatites in Angola. Apatite (U-Th-Sm)/He and phlogopite 40Ar/39Ar ages of Catanda aillikite lavas indicate eruption at ca. 500-800 ka, more than 100 m.y. after emplacement of abundant kimberlites and carbonatites in this region. The lavas share similar high-? (HIMU)-like Sr-Nd-Pb-Hf isotope compositions with other young mantle-derived volcanics from Africa (e.g., Northern Kenya Rift; Cameroon Line). The position of the Catanda complex in the Lucapa corridor, a long-lived extensional structure, suggests a possible tectonic control for the volcanism. The complex is also located on the Bié Dome, a broad region of fast Pleistocene uplift attributed to mantle upwelling. Seismic tomography models indicate convection of deep hot material beneath regions of active volcanism in Africa, including a large area encompassing Angola and northern Namibia. This is strong evidence that intraplate late Cenozoic volcanism, including the Catanda complex, resulted from the interplay between mantle convection and preexisting lithospheric heterogeneities.
DS201312-0645
2013
Mate, D.Nichols, K., Stachel, T., Pell, J., Mate, D.Diamond sources beneath the Hall Peninsula, Nunavut: a preliminary assessment based on micro-diamonds.Geoscience Forum 40 NWT, Poster abstract only p. 64Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS201312-0646
2013
Mate, D.Nichols, K., Stachel, T., Stern, R.A., Pell, J., Mate, D.Diamond sources beneath the Hall Peninsula, Nunavut: a preliminary assessment based on micro-diamonds.GAC-MAC 2013 SS4: Diamond: from birth in the mantle to emplacement in kimberlite, abstract onlyCanada, Nunavut, Hall PeninsulaMicrodiamonds
DS201312-0647
2013
Mate, D.J.Nichols, K.M.A., Stachel, T., Pell, J.A., Mate, D.J.Diamond sources beneath the Hall Peninsula, Baffin Island, Nunavut: preliminary assessment based on microdiamonds.Canada-Nunavut Geoscience Summary of Activities 2012, pp. 113-120.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS1992-1010
1992
Mate, K.Mate, K.Environmental impact of mining in Ghana: issues and answersNatural Resources forum, February pp. 49-53GhanaMining, Environment
DS1997-1160
1997
Mateen, A.Tllton, G.R., Mateen, A.lead, Strontium, neodymium isotope dat a from 30 and 300 Ma carbonatites in northwest Pakistan.Geological Association of Canada (GAC) Abstracts, PakistanCarbonatite, isotopes
DS1998-1464
1998
Mateen, A.Tilton, G.R., Bryce, J.G., Mateen, A.lead, Strontium, and neodymium isotope dat a from 30 and 300 Ma collision zone carbonatites in northwest Pakistan #2Journal of Petrology, Vol. 39, No. 11-12, Nov-Dec. pp. 1865-74.PakistanCarbonatite, Geochronology
DS1998-1465
1998
Mateen, A.Tilton, G.R., Bryce, J.G., Mateen, A.lead, Strontium, neodymium isotope dat a from 30 and 300 Ma collision zone carbonatites in Northwest Pakistan #1Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1521-2.PakistanCarbonatite, Geochronology
DS202205-0736
2022
Mateev, D.V.Zelenski, M., Plyasunov, A.V., Kamenetsky, V.S., Nikolai, N., Mateev, D.V., Korneeva, A.High-temperature water-olivine interaction and hydrogen liberation in the subarc mantle.Contributions to Mineralogy and Petrology, Vol. 177, 4. 10.1007/s00410-022-01910-zMantlewater

Abstract: Oxidized fluids in the subduction zone may convert polyvalent elements in the mantle to their higher valence states. The most abundant polyvalent element in the mantle is Fe, a significant part of which is contained in olivine as Fe2+. Results of the study of arc mantle xenoliths, in lab high-pressure-high-temperature experiments, and thermodynamic modeling have shown that at pressures of?~?50-2000 MPa and temperatures of 1000-1250 °C, well above the serpentine stability field, Fe2+ from olivine reacts with free aqueous fluid according to the following simplified reaction: 3Fe2SiO4?+?2H2O???3SiO2?+?2Fe3O4?+?2H2. The resulting ferric iron is preserved in spinel of a certain composition, (Mg,Fe2+)Fe3+2O4, whereas new high-Mg olivine, with magnesium number up to 96 in natural samples and 99.9 in experiments, forms in the reaction zone. SiO2 produced in the reaction either dissolves in the fluid or, with a small amount of water, reacts with olivine to form orthopyroxene as follows: (Mg,Fe)2SiO4?+?SiO2?=?(Mg,Fe)2Si2O6. The released H2 may decrease the oxidation state of polyvalent elements present in the fluid (e.g., S4+, S6+). Traces of high-temperature water-olivine interaction appear as swarms of fluid-spinel inclusions and are ubiquitous in olivine from ultramafic arc xenoliths. The described process is similar to serpentinization but occurs at higher pressure and temperature conditions and yields different reaction products. The reducing capacity of olivine is relatively low; however, given the large volume of mantle (and crustal) peridotites, the overall effect may be significant.
DS1997-0742
1997
Mateev, S.Mateev, S., Ballhaus, Fricke, Truckenbrodt, ZiegenbeinVolatiles in the Earth's mantle: I. Synthesis of CHO fluids at 1273 K and2.4 GPas.Geochimica et Cosmochimica Acta, Vol. 61, No. 15, pp. 3081-88.MantleGeochemistry - experimental
DS2001-0737
2001
Mateev, S.Mateev, S., O'Neill, H. St., Ballhaus, Taylor, GreenEffect of silica activity on OH IR spectra of olivine: implications for low aSiO2 mantle Metasomatism..Journal of Petrology, Vol. 42, No. 4, Apr. pp. 721-30.MantleMetasomatism - silica
DS200612-0874
2005
Mateev, S.Mateev, S., Stachel, T.FTIR spectroscopy of kimberlitic olivine: a new tool in diamond exploration.32ndYellowknife Geoscience Forum, p. 44 abstractTechnologySpectroscopy
DS200712-0697
2007
Mateev, S.Mateev, S., Stachel, T.Does kimberlitic magma degas at the MOHO?Geological Association of Canada, Gac-Mac Yellowknife 2007, May 23-25, Volume 32, 1 pg. abstract p.54.Canada, Northwest TerritoriesA154 Diavik, Grizzly Elati FTIR
DS201412-0668
2014
Mateev, S.Pearson, D.G., Brenker, F., Nestola, F., McNeil, J., Nasdala, L., Hutchison, M., Mateev, S., Mather, K., Silversmit, G., Schmitz, S., Vekemans, B., Vinczw=e, L.A hydrous mantle transition zone indicated by ring woodite included within diamond.Goldschmidt Conference 2014, 1p. AbstractMantleDiamond inclusion
DS201412-0669
2014
Mateev, S.Pearson, D.G., Brenker, F.E., Nestola, F., McNeill, J., Nasdala, L., Hutchinson, M.T., Mateev, S., Mather, K., Silversmit, G., Schmitz, S., Vekemans, B., Vincze, L.Hydrous mantle transition zone indicated by ring woodite included in diamond.Nature, Vol. 507, March 13, pp. 221-224.Mantle, South America, Brazil, Mato GrossoDiamond inclusion - water storage capacity, magmatism
DS201910-2306
2019
Matenco, L.C.Van Hinsbergen, D.J.J., Torsvik, T.H., Schmid, S.M., Matenco, L.C., Maffione, M., Vissers, R.L.M., Gurer, D., Spakman, W.Orogenic architecture of the Mediterranean region and kinematic reconstruction of its tectonic evolution since the Triassic. AtriaGondwana Research, in press available 427p.Europecraton

Abstract: The basins and orogens of the Mediterranean region ultimately result from the opening of oceans during the early break-up of Pangea since the Triassic, and their subsequent destruction by subduction accommodating convergence between the African and Eurasian Plates since the Jurassic. The region has been the cradle for the development of geodynamic concepts that link crustal evolution to continental break-up, oceanic and continental subduction, and mantle dynamics in general. The development of such concepts requires a first-order understanding of the kinematic evolution of the region for which a multitude of reconstructions have previously been proposed. In this paper, we use advances made in kinematic restoration software in the last decade with a systematic reconstruction protocol for developing a more quantitative restoration of the Mediterranean region for the last 240 million years. This restoration is constructed for the first time with the GPlates plate reconstruction software and uses a systematic reconstruction protocol that limits input data to marine magnetic anomaly reconstructions of ocean basins, structural geological constraints quantifying timing, direction, and magnitude of tectonic motion, and tests and iterations against paleomagnetic data. This approach leads to a reconstruction that is reproducible, and updatable with future constraints. We first review constraints on the opening history of the Atlantic (and Red Sea) oceans and the Bay of Biscay. We then provide a comprehensive overview of the architecture of the Mediterranean orogens, from the Pyrenees and Betic-Rif orogen in the west to the Caucasus in the east and identify structural geological constraints on tectonic motions. We subsequently analyze a newly constructed database of some 2300 published paleomagnetic sites from the Mediterranean region and test the reconstruction against these constraints. We provide the reconstruction in the form of 12 maps being snapshots from 240 to 0 Ma, outline the main features in each time-slice, and identify differences from previous reconstructions, which are discussed in the final section.
DS202106-0957
2021
Matende, K.Matende, K., Mickus, K.Magnetic and gravity investigation of kimberlites in north-central Botswana.Geophysics, Vol. 86, 2, B67-78.Africa, Botswanageophysics

Abstract: The Orapa kimberlite field of Botswana is one of the world’s major diamond producing regions. Within this field, there are several small kimberlite pipes that have not been completely explored in terms of their lateral extent, depth, and diamond potential. Two such pipes, BK54 and BK55, were found during a ground gravity and magnetic survey, and subsequent drilling confirmed the presence of kimberlite material. To determine the physical properties of these pipes, their lateral extent, depth, and thickness were estimated using a gravity and magnetic analysis and 2.5D and 3D modeling. Tilt derivatives of the magnetic data indicated that BK54 has a northwest-trending elliptical shape and BK55 has a roughly circular shape. Residual gravity anomaly maps indicate that BK54 does not have a density anomaly whereas BK55 is associated with a gravity maximum. The 3D gravity and magnetic inversion modeling constrained by magnetic susceptibility measurements indicates that BK54 is smaller in volume than BK55 and that neither pipe is thicker than 125 m. The difference in shape and the lack of a gravity anomaly over BK54 implies a different formation mechanism for each kimberlite pipe. Although several mechanisms are suggested, BK54 may have formed by a more explosive eruption producing more tuffistic material in the crater and diatreme facies. The gravity and magnetic analysis also found that the kimberlite pipes, while small, are larger in extent than was determined by drilling and warrant additional drilling to determine their economic potential.
DS200612-1259
2006
Matesanz, J-L.B.Seghedi, I., Szakacs, A., Pachero, A.H., Matesanz, J-L.B.Miocene lamproite volcanoes in south eastern Spain - an association of phreatomagmatic and magmatic products.Journal of Volcanology and Geothermal Research, In press, availableEurope, SpainLamproite
DS2002-1677
2002
MateusWaerenborgh, J.C., Figueoras, J., Mateus, Goncalves57Fe Mossbauer spectroscopy study of the correlation between Fe3+content and magnetic properties Cr spinelsEuropean Journal of Mineralogy, Vol.14,2,pp.437-46.GlobalSpectroscopy, Chrome spinels
DS202103-0403
2021
Mateus, A.Ribeiro da Costa, I., Roseiro, J., Figueiras, J., Rodrigues, P.C.R., Mateus, A.Pyrochlore from the Bailundo carbonatite Complex ( Angola): compositional variation and implications to mineral exploration.Journal of African Earth Sciences, Vol. 177, 104154, 16p. PdfAfrica, Angoladeposit - Bailundo

Abstract: Pyrochlore is a common accessory in carbonatite rocks and its composition can provide useful insights on petrogenetic and post-magmatic metal-enrichment processes, especially those which favour its occurrence and concentration. Comprehensive compositional and textural characterization of a large set of pyrochlores from the Bailundo Carbonatite Complex (SW Angola) and associated surface rocks was the basis to (i) evaluate the main effects of metasomatism and weathering as causes of metal leaching or concentration; and (ii) assess pyrochlore compositions as potential petrogenetic or metallogenetic tools, with particular emphasis on pyrochlore enrichment in economic components, such as Ta, REE, U, Th and Pb, during weathering processes. Unweathered fluor- and hydroxyl-calciopyrochlores from deep-seated carbonatitic rocks (provided by a 600 m-deep drill-core) often present high Ta/Nb ratios, as well as high U and Th contents, and comparatively low overall REE concentrations. Metasomatic effects are not easy to assess, given the extreme compositional variability of these pyrochlores. On the other hand, some systematic trends can be established in pyrochlores from weathered surface rocks: these pyrochlores usually show strong depletion in most A-site cations (e.g., Na, Ca, U), and clear enrichment in Nb and in large-ion metals (e.g., Ba, Sr, Pb) usually absent in unweathered pyrochlores. REE seem to be relatively immobile and to become concentrated during weathering. Along with some REE phosphates and oxides, pyrochlore is often present in several domains of the weathering profile, occurring in the outcropping weathered carbonatite as well as in the regolith immediately overlying the intrusion. Thus, both the Bailundo carbonatite intrusion and its weathering products, concentrated inside the ridge formed by differential erosion of the fenitic aureole, constitute good exploration targets for Nb (±Ta ± REE). However, future exploration work should also include a 3-D understanding of the chemical and geological processes at work in both geological environments.
DS202009-1655
2020
Mateus, A.M.Roseiro, J., Figueiras, J., Rodrigues, P.C.R., Mateus, A.M.Nb-bearing mineral phases in the Bailundo carbonatite complex ( Angola): implications of Nb geochemistry in metallogenesis.Communicacoes Geologicas *** in PORT, researchgate 7p. PdfAfrica, Angoladeposit - Bailundo

Abstract: Pyrochlore group minerals are common accessory phases in alkaline-carbonatitic complexes, and the most important Nb ore worldwide. Its capacity to embody a wide range of compositions can often provide useful insights in Nb occurrence and concentration processes. In the Bailundo Carbonatitic Complex (BCC, Angola), two major sets of pyrochlore can be distinguished: (1) magmatic/metasomatic pyrochlore in deep carbonatitic rocks, often displaying diffuse textures obliterating primary zoning, with slightly low contents in Nb2O5 (average 50 wt%), and in other chemical components (Ta, U, Na); and (2) supergene pyrochlore in the weathering profile, displaying corroded and bleached patches along microfractures (in some cases, with relics of magmatic pyrochlore), that show higher contents in Nb2O5 (up to 73 wt%), Ba and Pb. Compositional and textural variations recorded in pyrochlore crystals illustrate the geodynamic events that took place in the BCC and contributed to high Nb concentration in the weathering profile, thus being quite useful to distinguish different mineralization types and as Nb-exploration tools.
DS202103-0404
2020
Mateus, A.M.Roseiro, J., Figueiras, J., Rodrigues, P.C.N., Mateus, A.M. Nb-bearing mineral phases in the Bailiundo carbonatite complex, ( Angola): implications of Nb geochemistry in metallogenesis.Comminocacoes Geologicas ( Researchgate), July, 7p. PdfAfrica, Angoladeposit - Bailundo

Abstract: Pyrochlore group minerals are common accessory phases in many rock types of the Bailundo Carbonatite Complex. These minerals record compositional and textural features that provide useful information regarding their genesis and accumulation, monitoring magmatic, metasomatic and weathering events. In drill core samples, primary compositions (significant Ta and U contents, and relatively low Nb and F values) are found in relict cores of strongly metasomatized pyrochlore grains; irregular patches in pyrochlore rims, typically enriched in F, Na and Nb, reflect fluid alteration fronts. At shallower levels, preserved pyrochlores show well-defined concentric zoning and substantially higher values of F and Nb. In the weathering profile, alteration processes include replacement of F, Na and Ca by Ba, Sr, Pb and H2O. These data suggest the possibility of Nb concentration in late-magmatic fluids as fluoride complexes, and its subsequent mobilization and crystallization in the form of pyrochlore at shallower levels of the Bailundo Carbonatite Complex.
DS201512-1941
2015
Mather, A.E.Mather, A.E., Mills, S., Stokes, M., Fyfe, R.Ten years on: Google Earth offer the geoscience community?Geology Today, Vol. 31, 6, pp. 216-221.TechnologyGoogle Earth

Abstract: Google Earth has been part of most geoscientists' computer (and mobile) desktops for a decade, and this year Google Earth Professional has become freely available to all with a universal license key. Many users are still, however, not aware of the full potential that it can offer across a range of teaching and research areas in the geosciences. Here a pragmatic look is taken at some of the current key uses in terms of resources and applications and how they can help in research and training educational roles in the geosciences.
DS1950-0489
1959
Mather, A.L.Mather, A.L.Geochemical Prospecting Studies in Sierra LeoneLondon: Ph.d. Thesis, University London., UNPUB.Sierra Leone, West AfricaKimberlite, Diamond, Geochemistry
DS201212-0361
2012
Mather, D.G.Kjarsgaard, B.A., Mather, D.G., Pearson, S., Jackson, D., Crabtree, D., Creighton, S.CR-diopside and Cr-pyrope xenocryst thermobarometry revisited: applications to lithosphere studies and diamond exploration.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractCanadaGeobarometry
DS1998-0960
1998
Mather, J.Mather, J., Banks, D., Dumpleton, S., Fermor, M.Groundwater contaminants and their migrationsGeological Society of London Special Publication, No. 128, 320p. $ 115GlobalBook - ad, Groundwater management, hydrogeology
DS1998-0961
1998
Mather, J.Mather, J., Banks, D., Dumpleton, S., Fermor, M.Groundwater contaminants and their migrationGeological Society of London Special Publication, No. 128, 380pGlobalBook - table of contents, Groundwater, environmental
DS201412-0668
2014
Mather, K.Pearson, D.G., Brenker, F., Nestola, F., McNeil, J., Nasdala, L., Hutchison, M., Mateev, S., Mather, K., Silversmit, G., Schmitz, S., Vekemans, B., Vinczw=e, L.A hydrous mantle transition zone indicated by ring woodite included within diamond.Goldschmidt Conference 2014, 1p. AbstractMantleDiamond inclusion
DS201412-0669
2014
Mather, K.Pearson, D.G., Brenker, F.E., Nestola, F., McNeill, J., Nasdala, L., Hutchinson, M.T., Mateev, S., Mather, K., Silversmit, G., Schmitz, S., Vekemans, B., Vincze, L.Hydrous mantle transition zone indicated by ring woodite included in diamond.Nature, Vol. 507, March 13, pp. 221-224.Mantle, South America, Brazil, Mato GrossoDiamond inclusion - water storage capacity, magmatism
DS201910-2282
2019
Mather, K.Liu, J., Pearson, D.G., Mather, K., Kjarsgaard, B., Kopylova, M.Destruction and regeneration of cratonic lithosphere rocks: evidence from the Slave craton, Canada.Goldschmidt2019, 1p. AbstractCanada, Northwest Territoriesgeodynamics

Abstract: Cratons are the ancient landmasses that remain stable for billions of years on Earth but also have experienced episodic events of modification and rejuvenation throughout their history [1]. These alteration processes have modified the cratonic lithospheric mantle roots to different extents, e.g., ubiquitous cryptic/modal metasomatism, partial to entire loss of the mantle roots, to rifting apart of the craton. It remains unclear to what extent a cratonic mantle root can withstand modification and retain its integrity. We attempt to discuss this issue from the perspective of the Slave craton that has experienced the multiple impacts of major circum-cratonic Paleoproterozoic (1.93-1.84 Ga) orogenies and the intrusion of several 2.23-1.67 Proterozoic diabase dyke swarms. We use kimberlite-borne peridotite xenoliths to construct a N-S transect across the craton with an aim of probing the effects of these post-Archean events on the composition, age and depth of the lithospheric root. Chemically, all of these rocks are of typical cratonic refractory composition. P-T calculations and paleogeotherms show that they were derived from thick lithospheric mantle roots (>180 km), consistent with their diamondiferous nature. However, these peridotites exhibit variable N-S variation of modes in their Re-depletion Os model ages (TRD). Neoarchean TRD ages dominate in the Central and Southern Slave mantle. Progressing North there is a decreasing proportion of Archean TRD ages through Jericho to Artemisa in the Northern Slave craton. About 70% of the peridotites at Artemisia give TRD ages within error of the ~1.27 Ga Mackenzie LIP event, with the remaining (~ 30%) close to the Paleoproterozoic orogenic events. Combined with new data from regions to the N and NW of the Slave craton [2], the observed age spectrum in the far North of the craton indicates the likelihood of major new generation of lithospheric roots in both the Paleoproterozoic and Mesoproterozoic. Despite its complex history, the Northern Slave craton retains a ‘cratonic-like’ lithospheric root that allowed diamond mineralization.
DS200912-0481
2009
Mather, K.A.Mather, K.A., Pearson, D.G., Kjarsgaard, B.A., Stachel, T.A new look at Slave lithosphere paleogeotherms and the 'diamond window'.37th. Annual Yellowknife Geoscience Forum, Abstracts p. 42-3.Canada, Northwest TerritoriesGeothermometry
DS201012-0476
2010
Mather, K.A.Mather, K.A., Pearson, D.G., Kjarsgaard, B.A., Jackson, S.Understanding the lithosphere beneath Arctic Canada - an example from the N. Slave craton.38th. Geoscience Forum Northwest Territories, Abstract p. 65.Canada, Northwest TerritoriesDeposit - Artemisia
DS201112-0654
2011
Mather, K.A.Mather, K.A., Pearson, D.G., McKenzie, D., Kjarsgaard, B.A., Priestley, K.Constraints on the depth and thermal history of cratonic lithosphere from peridotite xenoliths, xenocrysts and seismology.Lithos, Vol. 125, pp. 729-742.Africa, South Africa, Canada, Somerset IslandGeothermometry, geophysics - seismics
DS201212-0546
2012
Mather, K.A.Pearson, D.G., Mather, K.A., Ishikawa, A., Kjarsgaard, B.A.Origin and evolution of cratonic roots.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalCraton
DS201312-0692
2013
Mather, K.A.Pearson, D.G., Brin, L., Liu, J., Riches, A., Stachel, T., Mather, K.A., Kjarsgaard, B.A.Canada's Arctic cratons: how many, how old, how come?2013 Yellowknife Geoscience Forum Abstracts, p. 49-50.Canada, Northwest Territories, Nunavut, Victoria Island, Parry PeninsulaGeochronology - mantle peridotites
DS201812-2860
2018
Mather, K.A.Pearson, D.G., Liu, J., Smith, C.B., Mather, K.A., Krebs, M.Y., Bulanova, G.P., Kobussen, A.F.Murowa deposit: Characteristics and origin of the mantle root beneath the Murowa diamond mine: implications for craton and diamond formation.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 403-424.Africa, Zimbabwedeposit - Murowa
DS202105-0774
2021
Mather, K.A.Liu, J., Pearson, D.G., Wang, L.H., Mather, K.A., Kjarsgaard, B.A., Schaeffer, A.J., Irvine, G.J., Kopylova, M.G., Armstrong, J.P.Plume-driven recratonization of deep continental lithospheric mantle.Nature, doi.org/101038/ s41586-021-03395-5 5p. PdfCanada, Northwest Territoriescraton

Abstract: Cratons are Earth’s ancient continental land masses that remain stable for billions of years. The mantle roots of cratons are renowned as being long-lived, stable features of Earth’s continents, but there is also evidence of their disruption in the recent1,2,3,4,5,6 and more distant7,8,9 past. Despite periods of lithospheric thinning during the Proterozoic and Phanerozoic eons, the lithosphere beneath many cratons seems to always ‘heal’, returning to a thickness of 150 to 200 kilometres10,11,12; similar lithospheric thicknesses are thought to have existed since Archaean times3,13,14,15. Although numerous studies have focused on the mechanism for lithospheric destruction2,5,13,16,17,18,19, the mechanisms that recratonize the lithosphere beneath cratons and thus sustain them are not well understood. Here we study kimberlite-borne mantle xenoliths and seismology across a transect of the cratonic lithosphere of Arctic Canada, which includes a region affected by the Mackenzie plume event 1.27 billion years ago20. We demonstrate the important role of plume upwelling in the destruction and recratonization of roughly 200-kilometre-thick cratonic lithospheric mantle in the northern portion of the Slave craton. Using numerical modelling, we show how new, buoyant melt residues produced by the Mackenzie plume event are captured in a region of thinned lithosphere between two thick cratonic blocks. Our results identify a process by which cratons heal and return to their original lithospheric thickness after substantial disruption of their roots. This process may be widespread in the history of cratons and may contribute to how cratonic mantle becomes a patchwork of mantle peridotites of different age and origin.
DS201112-0774
2011
Mather, K.S.Pearson, D.G., Tappe, S., Smart, K.A., Mather, K.S., Dale, C.W., Kjarsgaard, B.A.Crust mantle links in cratons.Goldschmidt Conference 2011, abstract p.1610.MantleSlave, Kaapvaal, coupling -decoupling
DS202106-0956
2021
Mather, T.A.Mason, E, Wieser, P.E., Liu, E.J., Edmonds, M., Ilyinskaya, E., Whitty, R.C., Mather, T.A., Elias, T., Nadeau, P.A., Wilkes, T.C., McGonigle, A.J.S., Pering, T.D., Mims, F.M., Kern, C., Schneider, D.J., Oppenheimer, C.Volatile metal emissions from volcanic gassing and lava-seawater interactions at Kilauea volcano, Hawaii.Earth & Environment Communications, 10.1038/s43247-021-00145-3 16p. PdfUnited States, Hawaiimagmatism

Abstract: Volcanoes represent one of the largest natural sources of metals to the Earth’s surface. Emissions of these metals can have important impacts on the biosphere as pollutants or nutrients. Here we use ground- and drone-based direct measurements to compare the gas and particulate chemistry of the magmatic and lava-seawater interaction (laze) plumes from the 2018 eruption of K?lauea, Hawai’i. We find that the magmatic plume contains abundant volatile metals and metalloids whereas the laze plume is further enriched in copper and seawater components, like chlorine, with volatile metals also elevated above seawater concentrations. Speciation modelling of magmatic gas mixtures highlights the importance of the S2? ligand in highly volatile metal/metalloid degassing at the magmatic vent. In contrast, volatile metal enrichments in the laze plume can be explained by affinity for chloride complexation during late-stage degassing of distal lavas, which is potentially facilitated by the HCl gas formed as seawater boils.
DS200612-0875
2001
Mathew, M.P.Mathew, M.P., Ramachandra, H.M., Gouda, H.C., Singh, R.K., Acharya, G.R., Murthy, C.V.V.S., Rao, K.S.IGRF corrected regional aeromagnetic anomaly map of parts of Peninsular India - potential for mapping and mineral exploration.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 395-405.India, Andhra Pradesh, Karnataka, Tamil Nadu, KeralaGeophysics - magnetics
DS1860-0563
1887
Mathews, J.W.Mathews, J.W.Incwadi Yami or Twenty Years Personal Experience in South Africa. Geology of the Diamond Fields.New York: Rogers And Sherwood., 542P. ALSO: MODERN REPRINT AFRICANA LIBRARY, Vol. 9, JOHANNEAfrica, South AfricaGeology
DS201808-1752
2018
Mathews, K.J.Hosseini, K., Mathews, K.J., Sigloch, K., Shephard, G.E., Domeier, M., Tsekhmistrenko, M.SubMachine: web based tools for exploring seismic tomography and other models of Earth's deep interior.Geochemistry, Geophysics, Geosystems, Vol. 19, 5, pp. 1464-1483.Mantlegeophysics - seismic

Abstract: SubMachine is a collection of web-based tools for the interactive visualisation, analysis, and quantitative comparison of global-scale, volumetric (3-D) data sets of the subsurface, with supporting tools for interacting with other, complementary models and data sets as listed below. In short, SubMachine is a computational engine (Machine) to visualize models and datasets of the sub-surface (Sub).
DS1982-0409
1982
Mathez, E.A.Mathez, E.A., Dietrich, V.J., Irving, A.J.Abundances of Carbon in Mantle Xenoliths from Alkalic BasaltProceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, PP. L99-200, (abstract.).GlobalKimberlite, Spinel, Lherzolite, Nunivak
DS1984-0492
1984
Mathez, E.A.Mathez, E.A., Blacic, J.D., Beery, J., Maggiore, C., Hollander.Carbon Abundances in Mantle Minerals Determined by Nuclear Reaction Analysis.Geophysical Research. LETTERS, Vol. 11, No. 10, OCTOBER, PP. 947-950.United States, Colorado Plateau, New MexicoXenolith, Crystallography
DS1984-0493
1984
Mathez, E.A.Mathez, E.A., Dietrich, V.J., Irving, A.J.The Geochemistry of Carbon in Mantle PeridotitesGeochimica et Cosmochimica Acta ., Vol. 49, No. 9, PP. 1849-1859.GlobalPetrology, Kimberlites, Alkali Basalts
DS1986-0533
1986
Mathez, E.A.Mathez, E.A., Blacic, J.D., Beery, J., Maggiore, C., Hollander, M.Carbon in olivine by nuclear reaction analysisProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 273-275GlobalBlank
DS1987-0443
1987
Mathez, E.A.Mathez, E.A.Carbonaceous matter in mantle xenoliths: composition and relevance to theisotopesGeochimica et Cosmochimica Acta, Vol. 51, pp. 2339-2347GlobalBlank
DS1987-0444
1987
Mathez, E.A.Mathez, E.A., Blacic, J.D., Beery, J., Hollander, M., Maggiore, C.Carbon in olivine: results from nuclear reaction analysisJournal of Geophys., Res, Vol. 92, No. B5, April 10, pp. 3500-3506GlobalMantle genesis
DS1989-0954
1989
Mathez, E.A.Mathez, E.A., Pineau, F.Carbon isotope compositions of xenoliths from the Hualalai Volcano, HawaiiEos, Vol. 70, No. 15, April 11, p. 510. (abstract.)HawaiiXenoliths
DS1989-1502
1989
Mathez, E.A.Tingle, T.N., Mathez, E.A., Becker, C.H.Constraints on the origin of organic compounds on crack surfaces in mantlexenolithsEos, Vol. 70, No. 43, October 24, p. 1411. AbstractNew MexicoSan Carlos, Xenoliths
DS1991-0125
1991
Mathez, E.A.Blacic, J.D., Mathez, E.A., Maggiore, C., Mitchell, T.E., Fogel, R.Oxygen in diamond by the nuclear microprobe: analytical technique and initial resultsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 20-22GlobalMicroprobe, Oxygen analyses
DS1991-1735
1991
Mathez, E.A.Tingle, T.N., Mathez, E.A., Hochella, M.F.Jr.Carbonaceous matter in peridotites and basalts studied by XPS, SALI, SOURCE[ Geochimica et Cosmochimica ActaGeochimica et Cosmochimica Acta, Vol. 55, pp. 1345-1352South AfricaKimberlite -Jagersfontein, Spectroscopy
DS1993-0980
1993
Mathez, E.A.Mathez, E.A., Blacic, J.D., Maggiore, C., Mitchell, T.E., Fogel, R.A.The determination of the O content of diamond by microactivationAmerican Mineralogist, Vol. 78, No. 7-8, July-August pp. 753-761.South Africa, Botswana, ZaireKimberlites, Deposit -Monastery, Finsch, Orapa, Muji Mayi
DS1995-1177
1995
Mathez, E.A.Mathez, E.A.Magmatic metasomatism and formation of the Merensky Reef, BushveldComplexContributions to Mineralogy and Petrology, Vol. 119, No. 2/3 pp. 277-286South AfricaMetasomatism, Deposit -Bushveld Complex
DS1995-1178
1995
Mathez, E.A.Mathez, E.A., Fogel, R.A., Hutcheon, I.D., Marshintsev, V.Carbon isotopic composition and origin of SIC from kimberlites of Russia.Geochimica et Cosmochimica Acta, Vol. 59, No. 4, Feb. pp. 781-792.Russia, YakutiaGeochronology
DS2003-0807
2003
Mathez, E.A.Li, C., Ripley, E.M., Mathez, E.A.The effect of S on the partitioning of Ni between olivine and silicate melt in MORBChemical Geology, Vol. 201, 3-4, pp. 293-306.MantleGeochemistry - nickel
DS200412-1125
2003
Mathez, E.A.Li, C., Ripley, E.M., Mathez, E.A.The effect of S on the partitioning of Ni between olivine and silicate melt in MORB.Chemical Geology, Vol. 201, 3-4, pp. 293-306.MantleGeochemistry - nickel
DS1940-0214
1949
Mathias, M.Mathias, M.Two Olivines from South African Melilite BasaltsMineralogical Magazine., Vol. 28, No. 204, PP. 486-491.South AfricaPetrography
DS1960-1012
1968
Mathias, M.Rickwood, P.C., Mathias, M., Siebert, J.C.A Study of Garnets from Eclogite and Peridotite Xenoliths Found Inkimberlite.Contributions to Mineralogy and Petrology, Vol. 19, pp. 271-301.South AfricaGarnet Mineralogy, Deposit - Bultfontein, De Beers, Dutoitspan, Kamfersdam
DS1960-1013
1968
Mathias, M.Rickwood, P.C., Mathias, M., Siebert, J.C.A Study of Garnets from Eclogite and Peridotite Xenoliths Found in Kimberlite.Contributions to Mineralogy and Petrology, Vol. 19, No. 4, PP. 271-301.South AfricaPetrography, Mineralogy
DS1960-1164
1969
Mathias, M.Mathias, M., Rickwood, P.C.Ultramafic Xenoliths in the Matsoku Kimberlite Pipe, Lesotho in Upper Mantle Project.Geological Society of South Africa SPECIAL Publishing, No. 2, PP. 359-369.LesothoGeology
DS1970-0133
1970
Mathias, M.Mathias, M., Siebert, J.C.L., Rickwood, P.C.Some Aspects of the Mineralogy and Petrology of Ultramafic Xenoliths in Kimberlite.Contributions to Mineralogy and Petrology, Vol. 26, No. 2, PP. 75-123.Tanzania, East AfricaMineralogy, Petrology
DS1970-0184
1970
Mathias, M.Rickwood, P.C., Mathias, M.Diamondiferous Eclogite Xenoliths in KimberliteLithos, Vol. 3, No. 3, PP. 223-235.South AfricaPetrology, Petrography
DS1970-0301
1971
Mathias, M.Gurney, J.J., Mathias, M., Siebert, C., Moseley, G.Kyanite Eclogites from the Rietfontein Kimberlite Pipe, Mier Coloured Reserve, Gordonia, Cape Province, South Africa.Contributions to Mineralogy and Petrology, Vol. 30, No. 1, PP. 46-52.South AfricaMineralogy
DS200812-0722
2008
Mathieu, L.Mathieu, L., Van Wyk de Vries, B., Holohan, E.P., Troll, V.R.Dykes, cups, saucers, sills: analogue experiments on magma intrusion into brittle rocks.Earth and Planetary Science Letters, Vol. 271, 1-4, pp. 1-13.MantleMagmatism
DS200812-0723
2008
Mathieu, L.Mathieu, L., Van Wyk de Vries, B., Holohan, E.P., Troll, V.R.Dykes, cups, saucers and sills: analogue experiments on magma intrusion into brittle rocks.Earth and Planetary Science Letters, Vol. 271, 1-4, pp. 1-13.MantleMagmatism
DS1910-0557
1918
Mathiez, F.F.Mathiez, F.F.Sampling Diamond DepositsMining and Scientific Press, Vol. 116, MARCH 9TH. P. 324.Democratic Republic of Congo, Central AfricaMining Engineering, Prospecting, Evaluation
DS1989-0955
1989
Mathison, C.I.Mathison, C.I.Petrological encoding of cumulatesTransactions of the Institute of Mining and Metallurgy (IMM), Vol. 98, No. B, Jan-April pp. B 18-B26GlobalLayered intrusion, Petrology
DS200612-0598
2006
Mathison, W.Holmes, P., Pell, J., Mathison, W., Strickland, D., Harder, M.New sparkle at the DO-27 diamond project.CIM Conference and Exhibition, Vancouver - Creating Value with Values, List of talks CIM Magazine, Feb. p. 78.Canada, Northwest TerritoriesOverview - Peregrine
DS200812-0876
2007
Mathison, W.Pell, J., Mathison, W., Friedland, E.V., Crawford, J.DO-27 and beyond: an update on Peregrine Diamonds programs in the Slave Province.35th. Yellowknife Geoscience Forum, Abstracts only p. 46-47.Canada, Northwest TerritoriesExploration - overview
DS1996-0901
1996
Mathu, E.M.Mathu, E.M.Geology and the environment of KenyaJournal of African Earth Sciences, Vol. 23, No. 4, Nov. 1, pp. 511-540KenyaGeology, Environment
DS1970-0134
1970
Mathur, P.C.Mathur, S.M., Mathur, P.C., Shrivastava, S.R., et al.The Diamond Bearing Conglomerates of the Panna Area, M.pSymposium On Geology And Mineral Resources of Madhya Pradesh, PP. 51-52. (abstract.).India, Madhya PradeshRegional Geology
DS1970-0347
1971
Mathur, P.C.Mathur, S.M., Mathur, P.C., Seva dass, BALAGO POLAN, M.k.Report on the Preliminary Prospecting for Diamonds between Urki and Majhgawan, District Panna, M.p.India Geological Survey, UNPUBL.India, Madhya PradeshProspecting
DS201704-0625
2016
Mathur, R.Gold, D., Doden, A.G., Mbalu-Keswa, C., Tedeski, J.R., Mathur, R.The Rogue kimberlite dikes in Indiana County, Pennsylvania Part 1. unusual intrusive habit of kimberlite dikes in coal seams.Guidebook 81st annual field conference of Pennsylvania Geologists, Oct. 6-8, pp. 121-160.United States, PennsylvaniaDeposit - Rogue
DS201704-0626
2016
Mathur, R.Gold, D., Doden, A.G., Mbalu-Keswa, C., Tedeski, J.R., Mathur, R.Supplement to guidebook: Petrography of the Tanoma and Ernest kimberlites.Guidebook 81st annual field conference of Pennsylvania Geologists, Oct. 6-8, pp. 263-268.United States, PennsylvaniaDeposit - Rogue
DS200612-1400
2006
Mathur, S.Swami, R.K., Pundhir, N.K.S., Mathur, S.Utilization of kimberlite tailings in road works.Indian Highways, Ingenta 1062075270, Vol. 34, 4, pp. 51-62.IndiaMining - environment
DS1950-0145
1953
Mathur, S.M.Mathur, S.M.Diamond Mining and Recovery at the Majhgawan Mine, in Pannavindhya Pradesh.Indian Minerals, Vol. 7, No. 1, PP. 34-42.India, Madhya PradeshDiamond Mining Recovery, Kimberlite Pipes, Engineering
DS1950-0183
1954
Mathur, S.M.Mathur, S.M.Manual Recovery, Administration and Production of the Pannadiamonds.Indian Minerals, Vol. 7, No. 4, PP. 196-203.IndiaMining Methods
DS1950-0184
1954
Mathur, S.M.Mathur, S.M.New Sediments in the Rewa Series ( Upper Vindhyan System) from the Setia district, Vindhya Pradesh.Current Science., Vol. 23India, Madhya PradeshGeology
DS1950-0226
1955
Mathur, S.M.Mathur, S.M.Indian Diamonds. Indian MineralsJournal of Gemology, Vol. 5, No. 2, APRIL PP. 73-76.India, Madhya PradeshBlank
DS1950-0227
1955
Mathur, S.M.Mathur, S.M.Some Aspects of Diamond Mining and Milling in PannaIndian Minerals, Vol. 9, No. 3 PP.India, Madhya PradeshBlank
DS1950-0228
1955
Mathur, S.M.Mathur, S.M.The Panna Diamond IndustryIndian Mining Journal, Vol. 3, No. 11.India, PannaHistory
DS1950-0337
1957
Mathur, S.M.Mathur, S.M.Industrial Diamonds from Panna, IndiaIndustrial Diamond Review., Vol. 17, DECEMBER PP. 227-228, P. 238.India, Madhya Pradesh, PannaHistory
DS1950-0412
1958
Mathur, S.M.Mathur, S.M.Five Years of the Panna Diamond Mining IndustryIndian Minerals, Vol. 12, No. 4, PP.India, Madhya PradeshBlank
DS1960-0168
1961
Mathur, S.M.Mathur, S.M.Report on the Geological Mapping on Aerial Photographs of The Diamond Bearing Areas and Investigation of Newly Located Ultramafic Pipes in Panna.India Geological Survey, UNPUBL.India, Madhya PradeshGeology, Sensing
DS1960-0275
1962
Mathur, S.M.Mathur, S.M.Geology of the Panna Diamond DepositsIndia Geological Survey Records, Vol. 87, No. 4, PP. 135-166.India, Madhya PradeshGeology
DS1960-0276
1962
Mathur, S.M.Mathur, S.M., Singh, H.N.Geology and Sampling of the Majhgawan Diamond Deposit, Panna District, Madhya Pradesh.India Geological Survey Bulletin. Ser. A, Economic Geology, No. 21, 59P. INDIA Geological Survey RECORDS, Vol. 87, PT. 4, PP.India, Madhya PradeshProspecting, Sampling
DS1970-0134
1970
Mathur, S.M.Mathur, S.M., Mathur, P.C., Shrivastava, S.R., et al.The Diamond Bearing Conglomerates of the Panna Area, M.pSymposium On Geology And Mineral Resources of Madhya Pradesh, PP. 51-52. (abstract.).India, Madhya PradeshRegional Geology
DS1970-0347
1971
Mathur, S.M.Mathur, S.M., Mathur, P.C., Seva dass, BALAGO POLAN, M.k.Report on the Preliminary Prospecting for Diamonds between Urki and Majhgawan, District Panna, M.p.India Geological Survey, UNPUBL.India, Madhya PradeshProspecting
DS1970-0348
1971
Mathur, S.M.Mathur, S.M., Singh, H.N.Petrology of the Majhgawan Pipe RockIndia Geological Survey Miscellaneous Publishing, No. 19, PP. 78-85.India, Madhya PradeshPetrology
DS1970-0758
1973
Mathur, S.M.Mathur, S.M.Chemical Composition of the Majhgawan Kimberlite, Central India.International Kimberlite Conference FIRST, ABSTRACT VOLUME., PP. 211-212.India, Madhya PradeshGeochemistry
DS1975-0559
1977
Mathur, S.M.Mathur, S.M.Prospecting for Diamonds in IndiaThe New Sketch, Republic Day Special, PP. 175-191.India, Madhya PradeshProspecting
DS1975-0560
1977
Mathur, S.M.Mathur, S.M.Stratigraphic Position of the Diamond Bearing Conglomerates of the Panna Area.Chayanica Geologica., Vol. 3, No. 1, PP.India, Madhya PradeshStratigraphy, Genesis
DS1982-0410
1982
Mathur, S.M.Mathur, S.M.The Diamond Deposits of IndiaIndiaqua., No. 33, PP. 21-24.India, Madhya PradeshDiamond Occurrences
DS1983-0436
1983
Mathur, S.M.Mathur, S.M., Alexander, P.O.Preliminary Pedogeochemical and Biogeochemical Studies on The Hinota Kimberlite, Panna District, India.Indian Academy of Science Proceedings, Vol. 92, No. 1, MARCH, PP. 81-88.India, Panna, Madhya PradeshGeochemistry
DS1986-0534
1986
Mathur, S.M.Mathur, S.M.Panna mine revisitedIndiaqua, No. 44, 1986/II, pp. 23, 24, 27IndiaHistory, News item
DS1998-1322
1998
MathyShanker, R., Singh, Kumar, MathyPre-Gondwana events and evolution of the Indian subcontinent as part ofGondwana.Journal of African Earth Sciences, Vol. 27, 1A, p. 178. AbstractIndiaTectonics
DS200412-0354
2004
Matias, L.Contrucci, I., Matias, L., Moulin, M., Geli, L., et al.Deep structure of the West African continental margin between 5S and 8S from reflection refraction seismics and gravity data.Geophysical Journal International, Vol. 158, 2, pp. 529-553.Africa, Democratic Republic of Congo, AngolaGeophysics - seismics
DS201810-2353
2018
Matias, M.M.A.Matias, M.M.A., vander Neut, J.Marchenko imaging by unidimensional deconvolution.Geophysical Prospecting, doi.10.111/1365-2478.12686Mantlegeophysics

Abstract: Obtaining an accurate image of the subsurface still remains a great challenge for the seismic method. Migration algorithms aim mainly on positioning seismic events in complex geological contexts. Multiple reflections are typically not accounted for in this process, which can lead to the emergence of artefacts. In Marchenko imaging, we retrieve the complete up? and downgoing wavefields in the subsurface to construct an image without such artefacts. The quality of this image depends on the type of imaging condition that is applied. In this paper, we propose an imaging condition that is based on stabilized unidimensional deconvolution. This condition is computationally much cheaper than multidimensional deconvolution, which has been proposed for Marchenko imaging earlier. Two specific approaches are considered. In the first approach, we use the full up? and downgoing wavefields for deconvolution. Although this leads to balanced and relatively accurate amplitudes, the crosstalk is not completely removed. The second approach is to incorporate the initial focussing function in the deconvolution process, in such a way that the retrieval of crosstalk is avoided. We compare images with the results of the classical cross?correlation imaging condition, which we apply to reverse?time migrated wavefields and to the up? and downgoing wavefields that are retrieved by the Marchenko method.
DS2003-1442
2003
Matias, O.Walker, J.A., Roggensack, K., Patino, L.C., Cameron, B.I., Matias, O.The water and trace element contents of melt inclusions across an active subductionContributions to Mineralogy and Petrology, Vol. 146, 1, pp. 62-77.MantleSubduction - water
DS2003-1443
2003
Matias, O.Walker, J.A., Roggensack, K., Patino, L.C., Cameron, B.I., Matias, O.The water and trace element contents of melt inclusions across an active subductionContributions to Mineralogy and Petrology, Vol. 10.1007/s00410-003-0432-xMantleBlank
DS200412-2072
2003
Matias, O.Walker, J.A., Roggensack, K., Patino, L.C., Cameron, B.I., Matias, O.The water and trace element contents of melt inclusions across an active subduction zone.Contributions to Mineralogy and Petrology, Vol. 146, 1, pp. 62-77.MantleSubduction - water
DS1996-0509
1996
Matieshin, S.D.Gendzwill, D.J., Matieshin, S.D.Seismic reflection survey of a kimberlite intrusion in the Fort a la Cornedistrict, Saskatchewan.Geological Survey of Canada, LeCheminant ed, OF 3228, pp. 251-253.SaskatchewanGeophysics -seismics, Fort a la Corne area
DS1993-1604
1993
Matile, G.Thorleifson, L.H., Matile, G.Till geochemistry and indicator mineral reconnaissance of southeasternManitoba.Geological Survey of Canada Open File, No. 2750, 1 disk. $ 15.00ManitobaGeochemistry, Kimberlite indicator minerals
DS1994-1774
1994
Matile, G.Thorleifson, L.H., Garrett, R.G., Matile, G.Prairie kimberlite study: indicator mineral geochemistryGeological Survey of Canada Open file, No. 2875Alberta, Western CanadaGeochemistry
DS1994-1775
1994
Matile, G.Thorlieffson, L.H., Garrett, R.G., Matile, G.Prairie kimberlite study - indicator mineral geochemistryGeological Survey of Canada Open File, No. 2875, 1 disc. $ 15.00SaskatchewanGeochemistry, Indicator minerals
DS1996-0902
1996
Matile, G.Matile, G., Nielsen, E., Thorleifson, H., Garrett, R.G.Follow up kimberlite indicator mineral survey of western ManitobaGeological Survey of Canada Colloquium, Jan. 22-24th., Poster display onlyManitobaExploration, Geomorphology, geochemistry
DS1996-1430
1996
Matile, G.Thorleifson, L.H., Matile, G.Indicator mineral and till geochemical reconnaissance of southeasternManitoba.Geological Survey of Canada Colloquium, Jan. 22-24th., Poster display onlyManitobaExploration, Geochemistry, geomorphology
DS1997-0338
1997
Matile, G.Fedikow, M.A.F., Nielsen, E., Conley, G.G., Matile, G.Operation Superior: multimedia geochemical surveys Edmund Lake, Sharpe lake greenstone belt #1Man. Geological Survey Report Activities, pp. 4-5.ManitobaGeochemistry - exploration
DS1998-0413
1998
Matile, G.Fedikow, M.A.F., Nielsen, E., Conley, G.G., Matile, G.Operation Superior: multimedia geochemical surveys Edmund Lake, Sharpe lake greenstone belt #2Man. Geological Survey Open File, No. 98-5, 410p.ManitobaGeochemistry - exploration
DS200412-0178
2004
Matile, G.L.Bohm, C.O., Kasycki, C.A., Lenton, P.G., Syme, E.C., Keller, G.R., Matile, G.L.Revealing Manitoba's hidden kimberlites.Geological Association of Canada Abstract Volume, May 12-14, SS14-01 p. 260.abstractCanada, ManitobaBrief overview of structure, stratigraphy
DS1992-1550
1992
Matile, G.L.D.Thorleifson, L.H., Matile, G.L.D.Environmental geology, geochemistry and kimberlite indicator mineral tracing in southern Manitoba.Man. Geological Survey Convention '92, p. abstract.ManitobaGeochemistry - exploration
DS1994-1123
1994
Matile, G.L.D.Matile, G.L.D., Nielsen, E.Kimberlite indicator follow up project, West lake Plain, southwestern Manitoba.Man. Geological Survey Report Activities, pp. 179-81.ManitobaGeochemistry - exploration
DS1996-0903
1996
Matile, G.L.D.Matile, G.L.D., Nielsen, E., Thorleifson, L.H., GarrettKimberlite indicator mineral analysis from the West lake Plain: follow up to Geological Society of Canada (GSC) Prairie kimberlite study.Man. Geological Survey Open File, No. 96-2, 39p.ManitobaGeochemistry - exploration, Westlake Plain
DS1997-1155
1997
Matile, G.L.D.Thorleifson, L.H., Matile, G.L.D.Till geochemistry and indicator mineral reconnaissance of northeasternManitoba.Geological Survey of Canada Open file, No. D3449, 1 disc. approx. $ 20.00GlobalGeochemistry - till, Indicator minerals
DS1997-1156
1997
Matile, G.L.D.Thorleifson, L.H., Matile, G.L.D.Quaternary geology of southeastern ManitobaGeological Survey of Canada (GSC) Forum 1997, p. 23.ManitobaGeochemistry - exploration, Geomorphology
DS1997-1157
1997
Matile, G.L.D.Thorleifson, L.H., Matile, G.L.D.Prairie kimberlite study till matrix geochemistry and preliminary indicator mineral data.Geological Survey of Canada (GSC) Open File, No. 2745SaskatchewanGeochemistry - exploration, Geomorphology
DS1999-0737
1999
Matile, G.L.D.Thorleifson, L.H., Matile, G.L.D.Till geochemical and indicator mineral reconnaissance of northeasternManitoba.Geological Association of Canada (GAC) Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)., Vol. 24, p. 128. abstractManitobaGeochemistry, Indicator mineralogy
DS200412-0149
2004
Matile, G.L.D.Bezys, R.K., Matile, G.L.D., Bamburak, J.D.Hudson Bay Lowland Phanerozoic stratigraphy: recent developments.Manitoba Geological Survey, Report of Activities Nov. 18-20, abstractCanada, ManitobaStratigraphy
DS200412-0968
2004
Matile, G.L.D.Keller, G.R., Bodgan, D.J., Matile, G.L.D.Manitoba kimberlite indicator mineral database Version 2.0.Manitoba Geological Survey, Canada, ManitobaGeochemistry - database
DS200912-0061
2008
Matile, G.L.D.Bohm, C.O., Anderson, S.D., Matile, G.L.D., Keller, G.R.Geochemical and kimberlite indicator mineral results for till samples from Nejanilini, Kasmere and Putahow lakes areas, northern Manitoba NTS 64N 64 O 64 P.Manitoba Geological Survey, OF 2008-13, CDCanada, ManitobaGeochemistry
DS1997-0364
1997
Matile, S.S.Fulton, R.J., Thorleifson, L.H., Blais, A., Matile, S.S.Southern Prairies NATMAP project: a summary reportGeological Survey of Canada Forum 1997 abstracts, p. 6. AbstractGlobalSurficial geology
DS202005-0750
2020
Matin, A.Mukhopadhyay, D., Matin, A.The architecture and evolution of the Singhbhum craton.Episodes ( IUGS), Vol. 43, 1, pp. 19-50.Indiacraton

Abstract: The Singhbhum Craton is built up by successive pulses of discrete granitic magmatism at ~3.52 Ga, ~3.47-3.43 Ga, and ~3.40-3.35 Ga that produced tonalitetrondhjemite-granodiorite (TTG)-type suites and were followed by younger pulses at 3.32-3.35 Ga, and 3.31-3.28 Ga producing voluminous granitic-granodioritic magma. There is enough evidence to indicate that continental crust building activity started in the Hadean time and continued through Eoarchean. But the rocks of this period were fully recycled to generate the Paleoarchean and younger crust. The different pulses of granitic magmatism during the Paleoarchean were interspersed with the formation of supracrustal rocks which are now preserved as supracrustal belts peripheral to the craton or as internal screens within the craton. Halfnium isotopic record suggests that the Hadean and Eoarchean granitoids were sourced in an enriched reservoir, probably some form of early mafic protocrust. From ~3.6-3.5 Ga a shift in the isotopic composition of Hf is noticed, marked by upward excursion of ?Hf(t) plots towards suprachondritic values, signifying that the early mantle reservoir was serially modified by contamination by a juvenile melt derived from a depleted source. This probably signals a change in the geodynamic scenario, major depletion of the mantle and generation of voluminous TTG melts. There are contending hypotheses of plume-driven and subduction-driven mechanisms of continental crust formation. In the Singhbhum Craton during Hadean and Eoarchean times episodic mantle plumes probably operated in a stagnant lid tectonic setting. Repeated plume activities and the formation of oceanic plateaus might have triggered the onset of subduction which at the initial stages might have been of short duration. The transition from plume-driven tectonics to subduction-driven tectonics might have taken place at about 3.5 Ga. The supracrustal belts of the Older Metamorphic Group (OMG) and the Iron Ore Group (IOG) are thought to have formed in supra-subduction settings. Widespread metamorphism and deformation affected the craton during 3.34-3.26 Ga. By 3.1 Ga the Singhbhum Craton had stabilized and emerged as a landmass. Paleosols developed on the surface; rift basins were formed which were receptacles of siliciclastic sediments and mafic volcanics; anorogenic K-feldspar bearing granites were emplaced. Swarms of mafic dykes of Paleo- to Meso-Proterozoic age intruded the craton marking a tensional regime that was probably related to the initial stage of basin formation in the North Singhbhum Mobile Belt.
DS202009-1642
2000
Matin, A.Mukhopadhyay, D., Matin, A.The architecture and evolution of the Singbhum craton.Episodes, Vol. 43, 1, pp. 19- 50.Indiamagmatism

Abstract: The Singhbhum Craton is built up by successive pulses of discrete granitic magmatism at ~3.52 Ga, ~3.47-3.43 Ga, and ~3.40-3.35 Ga that produced tonalitetrondhjemite-granodiorite (TTG)-type suites and were followed by younger pulses at 3.32-3.35 Ga, and 3.31-3.28 Ga producing voluminous granitic-granodioritic magma. There is enough evidence to indicate that continental crust building activity started in the Hadean time and continued through Eoarchean. But the rocks of this period were fully recycled to generate the Paleoarchean and younger crust. The different pulses of granitic magmatism during the Paleoarchean were interspersed with the formation of supracrustal rocks which are now preserved as supracrustal belts peripheral to the craton or as internal screens within the craton. Halfnium isotopic record suggests that the Hadean and Eoarchean granitoids were sourced in an enriched reservoir, probably some form of early mafic protocrust. From ~3.6-3.5 Ga a shift in the isotopic composition of Hf is noticed, marked by upward excursion of ?Hf(t) plots towards suprachondritic values, signifying that the early mantle reservoir was serially modified by contamination by a juvenile melt derived from a depleted source. This probably signals a change in the geodynamic scenario, major depletion of the mantle and generation of voluminous TTG melts. There are contending hypotheses of plume-driven and subduction-driven mechanisms of continental crust formation. In the Singhbhum Craton during Hadean and Eoarchean times episodic mantle plumes probably operated in a stagnant lid tectonic setting. Repeated plume activities and the formation of oceanic plateaus might have triggered the onset of subduction which at the initial stages might have been of short duration. The transition from plume-driven tectonics to subduction-driven tectonics might have taken place at about 3.5 Ga. The supracrustal belts of the Older Metamorphic Group (OMG) and the Iron Ore Group (IOG) are thought to have formed in supra-subduction settings. Widespread metamorphism and deformation affected the craton during 3.34-3.26 Ga. By 3.1 Ga the Singhbhum Craton had stabilized and emerged as a landmass. Paleosols developed on the surface; rift basins were formed which were receptacles of siliciclastic sediments and mafic volcanics; anorogenic K-feldspar bearing granites were emplaced. Swarms of mafic dykes of Paleo- to Meso-Proterozoic age intruded the craton marking a tensional regime that was probably related to the initial stage of basin formation in the North Singhbhum Mobile Belt.
DS201906-1320
2019
Matindi, T.B.Matindi, T.B., Naidoo, S.R., Ntwaeaborwa, O.M.Luminesence induced by N-O ion implantation into diamond.Diamond & Related Materials, Vol. 96, pp. 11-19.Globalphotoluminescence

Abstract: The incorporation of shallow n-type dopants in diamond is one of the major challenges for its electronic applications. n-Type behaviour in diamond has been observed for substitutional phosphorus and nitrogen, with activation energies of approximately 0.62 and 1.7?eV, respectively. Both nitrogen and phosphorus are deep lying substitutional impurity states in diamond. It has been theoretically found that the substitution of the NO molecule into the diamond lattice forms a stable defect in the band gap and, in the negatively charged state induces a shallow defect below the conduction band edge which may lead to n-type conductivity. In this study, low-temperature photoluminescence measurements using different excitation wavelengths were used to investigate the nature and behaviour of the defects induced by the implantation of NO ions into type IIa Chemical Vapor Deposition (CVD) diamond samples. Luminescence peaks were observed at 293.3, 297.3, 305.9, 309.8, 314.4 and 556.7?nm on the sample which was implanted by NO ions and annealed at 600?°C. The origin of these peaks is discussed and the mechanism of electronic transitions leading to emission of photoluminescence from these samples is proposed.
DS2002-1168
2002
Matinotti, G.Oberhansli, R., Matinotti, G., Schmid, R., Liu, X.Preservation of primary volcanic textures in the ultrahigh pressure terrain of Dabie ShanGeology, Vol.30,8,Aug.pp.699-702.ChinaUHP, Deposit - Dabie Shan area
DS201412-0559
2014
Matjuschkin, V.Matjuschkin, V., Brey, G.P.The influence of Fe3+ on garnet-orthopy roxene and garnet-olivine geothermometers.Contributions to Mineralogy and Petrology, Vol. 167, pp. 972- ( 11p).TechnologyGeothermometry
DS202106-0921
2021
Matkovic, K.Antonini, A., Ganuza, M.L. , Ferracutti, G., Gagiulo, M.F., Matkovic, K., Groller, E., Bjerg, E.A., Castro, S.M.Spinel web: an interactive web application for visualizing the chemical composition of spinel group minerals. ** not specific to diamondsEarth Science Informatics, Vol. 14, pp. 521-528. pdfMantletectonics

Abstract: The spinel group minerals provide useful information regarding the geological environment in which the host rocks were formed, constituting excellent petrogenetic indicators, and guides in the search for mineral deposits of economic interest. In this article, we present the Spinel Web, a web application to visualize the chemical composition of spinel group minerals. Spinel Web integrates most of the diagrams commonly used for analyzing the chemical characteristics of the spinel group minerals. It incorporates parallel coordinates and a 3D representation of the spinel prisms. It also provides coordinated views and appropriate interactions for users to interact with their datasets. Spinel Web also supports semi-automatic categorization of the geological environment of formation through a standard Web browser.
DS201412-0256
2014
Matlins, A.Fritsch, E., Toledo, V., Matlins, A.Record size natural moissanite crystals discovered in Isreal.Gems & Gemology, Vol 50, 2, summer 2p.Europe, IsraelMoissanite
DS1984-0494
1984
Matlins, A.L.Matlins, A.L., Bonanno, A.C.The Complete Guide to Buying GemsCrown Publishing, 206P.GlobalDiamonds, Kimberley
DS202011-2065
2020
Matmon, A.Vainer, S., Matmon, A., Erel, A.J., Hidy, A.J., Crouvi, O., De Wit, M., Geller, Y.Landscape responses to intraplate deformation in the Kalahari constrained by sediment provenance and chronology in the Okavango Basin.Basin Research, in press available Africa, South Africageomorphology

Abstract: The structural depression that occupies the Okavango Basin in southern Africa comprises a depo?centre within the intracratonic Kalahari Basin where sediments of the Cenozoic Kalahari Group have accumulated. The Okavango Basin has been formed due to stretching and subsidence at an area of diffused deformation, southwestwards to the main East African Rift System (EARS). Sediments from two full Kalahari Group sequences, located on opposite sides of the Gumare Fault that forms a major fault within the Okavango Basin, were studied to determine their provenance and chronology. Terrestrial Cosmogenic Nuclide (TCN) 26Al/10Be burial dating was used to constrain a chronostratigraphical framework, and Pb, Sr, and Nd isotopic ratios combined with geochemical and sedimentological analyses were applied to track the source areas of the sediments.Results indicate the following sequence of basin filling: (a) Accumulation between ca. 4-3 Ma during which the currently downthrown (southern) block received a mixture of sediments mostly from the Choma?Kalomo, Ghanzi?Chobe, and Damara terranes, and possibly from the Lufilian Belt and/or Karoo basalts during earlier stages of deposition. Simultaneously, the upthrown (northern) block received sediments from more distant Archean sources in the Zimbabwe and/or Kasai cratons, (b) Hiatus in sedimentation occurred at both sites between ca. 3-2 Ma, (c) Sediments on both sides of the Gumare Fault share a similar source (Angolan Shield) with minor distinct contributions to the downthrown block from the Kasai Craton and local sources input to the upthrown block, and (d) Regional distribution of aeolian sand since at least 1 Ma. The change in source areas is attributed to rearrangements of the drainage systems that were probably linked to vertical crustal movements on the margins of the Okavango Basin. The tectonically induced morphodynamics controlled the landscape evolution of the endorheic basin where vast lakes, wetlands and salt pans have developed through time.
DS2000-0629
2000
Matos, J.B.Matos, J.B., Gomes, C.B., Ruberti, Velazquez, V.F.Petrography and geochemistry of alkaline plugs from Sao Pedro, POr to Conceicao Morro Distante.Igc 30th. Brasil, Aug. abstract only 1p.Brazil, Mato GrossoAlkaline rocks, Paraguay Province
DS201212-0656
2012
Matos, L.Silveira, F.V., Britto, R.S., Matos, L., Araujo, D.P.Diamante Brasil project.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractSouth America, BrazilDeposit - Coromandel, Diamantina
DS201709-2043
2017
Matos, M.J.S.Pimenta Martins, L.G., Matos, M.J.S., Paschoal, A.R., Freire, P.T.C., Andrade, N.F., Aguiar, A.L., Kong, J., Neves, B.R.A., de Oliveira, A.B., Mazzoni, M.S.C., Souza Filhio, A.G., Cancad, L.G.Raman evidence for pressure induced formation of diamondene.Nature Communications, Vol. 8, 9p.Technologydiamondene

Abstract: Despite the advanced stage of diamond thin-film technology, with applications ranging from superconductivity to biosensing, the realization of a stable and atomically thick two-dimensional diamond material, named here as diamondene, is still forthcoming. Adding to the outstanding properties of its bulk and thin-film counterparts, diamondene is predicted to be a ferromagnetic semiconductor with spin polarized bands. Here, we provide spectroscopic evidence for the formation of diamondene by performing Raman spectroscopy of double-layer graphene under high pressure. The results are explained in terms of a breakdown in the Kohn anomaly associated with the finite size of the remaining graphene sites surrounded by the diamondene matrix. Ab initio calculations and molecular dynamics simulations are employed to clarify the mechanism of diamondene formation, which requires two or more layers of graphene subjected to high pressures in the presence of specific chemical groups such as hydroxyl groups or hydrogens.
DS1990-0995
1990
Matos, R.M.D.Matos, R.M.D.Deep seismic profile of the Amazonian craton (northern Brasil) #2Geological Society of America (GSA) Annual Meeting, Abstracts, Vol. 22, No. 7, p. A204BrazilGeophysics -seismics, Craton
DS2000-0630
2000
Matos, R.M.D.d.Matos, R.M.D.d.South Atlantic opening rifts in the Equatorial Atlantic?Igc 30th. Brasil, Aug. abstract only 1p.Africa, BrazilTectonics - rifting
DS1999-0447
1999
Matoshko, A.V.Matoshko, A.V.Quaternary glacial deposits and landforms of the north Timan region, Russia - a possible center glaciation.Gsa Mickelson And Attig Glacial Processes, Special Paper 337, pp.179-85.Russia, Kola PeninsulaGeomorphology - Valdai glaciation
DS200412-1245
2004
Matrenichev, V.A.Matrenichev, V.A., Vrevskii, A.B.Isotopic geochemical model for the upper mantle evolution of the Baltic Shield.Geochemistry International, Vol. 42, 1, pp. 86-91.Baltic Shield, Kola PeninsulaGeochronology
DS200412-1246
2004
Matrosov, V.A.Matrosov, V.A., Bornyakov, S.A., Gladkov, A.S.A new approach to optimization of prognostic prospecting for Diamondiferous kimberlites.Doklady Earth Sciences, Vol. 395, 2, pp. 192-195.RussiaDiamond prospecting technique
DS200512-0344
2005
Matrosov, V.A.Gladkov, A.S., Zinchuk, N.N, Bornyakov, S.A., Sherman, S.I., Manakov, A.V., Matrosov, V.A., Garat, DzyubaNew dat a on the internal structure and formation mechanism of kimberlite hosting fault zones in the Malaya Botuoba region, Yakutian Diamondiferous provinceDoklady Earth Sciences, Vol. 402, 4, pp. 520-23.Russia, YakutiaTectonics, structure, Malaya Botuoba
DS202006-0935
2020
Matrosova, E.A.Matrosova, E.A., Bobrov, A.V., Bindi, L., Pushcharovsky, D.Yu., Irifune, T.Titanium-rich phases in the Earth's transition zone and lower mantle: evidence from experiments in the system Mg)-Si)2-TiO2(+- Al2O3Lithos, Vol. 366-367, 14p. PdfMantlewebsterite, bridgmanite

Abstract: Phase relations in the MgSiO3-MgTiO3 and Mg3Al2Si3O12-MgTiO3 systems were studied at 10-24 GPa and 1600 °C using a high-pressure Kawai-type multianvil apparatus. We investigated the full range of starting compositions for the enstatite-geikielite system to derive a P-X phase diagram and synthesize titanium-bearing phases, such as olivine/wadsleyite, rutile, pyroxene, MgTiSi2O7 weberite, bridgmanite and MST-bridgmanite in a wide pressure range. Olivine and pyroxene in run products are characterized by a low titanium content (<0.6 and <0.3 wt% TiO2, respectively) whereas the content of TiO2 in wadsleyite reaches 2 wt% at 12 GPa. The concentration of Ti in MgTiSi2O7 weberite decreases with pressure from 52 wt% TiO2 at 14 GPa to 43 wt% TiO2 at 18 GPa. Two perovskite-type structures (MgSiO3 bridgmanite and Mg(Si,Ti)O3 bridgmanite) were detected in the studied system. MgSiO3 bridgmanite (Brd) is formed at a pressure of >20 GPa and characterized by significant titanium solubility (up to 13 wt% TiO2 at 24 GPa). Mg(Si,Ti)O3 perovskite is formed at a pressure of >17 GPa. The concentration of TiO2 in this phase varies from 29 wt% to 49 wt%. It was found that addition of Ti to the system moves the boundaries of Ol/Wad phase transformations to lower pressures. Addition of Al to the starting material allows us to simulate the composition of natural Ti-rich garnets and bridgmanites. It is important to note that garnet in the Prp-Gkl system is stable throughout a wide pressure range (10-24 GPa). Al incorporation does not affect the distribution of titanium between two types of bridgmanite. It is shown that high contents of Ti stabilize bridgmanite-like compounds at considerably lower pressure than that at the lower mantle/transition zone boundary. Our experiments simulate the composition of natural Ti-rich primary garnet found in eclogite from the Sulu ultrahigh-pressure (UHP) terrane.
DS202008-1420
2020
Matrosova, E.M.Matrosova, E.M., Bobrov, A.V., Bindi, L., Pushcharovsky, D.Yu., Irifune, T.Titanium rich phases in the Earth's transition zone and lower mantle: evidence from experiments in the system MgO-SiO2-TiO2(+-Al2O3) at 10-24 Gpa and 1600 C.Lithos, Vol. 366-367 1055539 14 p. pdfMantlebridgemanite

Abstract: Phase relations in the MgSiO3-MgTiO3 and Mg3Al2Si3O12-MgTiO3 systems were studied at 10-24 GPa and 1600 °C using a high-pressure Kawai-type multianvil apparatus. We investigated the full range of starting compositions for the enstatite-geikielite system to derive a P-X phase diagram and synthesize titanium-bearing phases, such as olivine/wadsleyite, rutile, pyroxene, MgTiSi2O7 weberite, bridgmanite and MST-bridgmanite in a wide pressure range. Olivine and pyroxene in run products are characterized by a low titanium content (<0.6 and <0.3 wt% TiO2, respectively) whereas the content of TiO2 in wadsleyite reaches 2 wt% at 12 GPa. The concentration of Ti in MgTiSi2O7 weberite decreases with pressure from 52 wt% TiO2 at 14 GPa to 43 wt% TiO2 at 18 GPa. Two perovskite-type structures (MgSiO3 bridgmanite and Mg(Si,Ti)O3 bridgmanite) were detected in the studied system. MgSiO3 bridgmanite (Brd) is formed at a pressure of >20 GPa and characterized by significant titanium solubility (up to 13 wt% TiO2 at 24 GPa). Mg(Si,Ti)O3 perovskite is formed at a pressure of >17 GPa. The concentration of TiO2 in this phase varies from 29 wt% to 49 wt%. It was found that addition of Ti to the system moves the boundaries of Ol/Wad phase transformations to lower pressures. Addition of Al to the starting material allows us to simulate the composition of natural Ti-rich garnets and bridgmanites. It is important to note that garnet in the Prp-Gkl system is stable throughout a wide pressure range (10-24 GPa). Al incorporation does not affect the distribution of titanium between two types of bridgmanite. It is shown that high contents of Ti stabilize bridgmanite-like compounds at considerably lower pressure than that at the lower mantle/transition zone boundary. Our experiments simulate the composition of natural Ti-rich primary garnet found in eclogite from the Sulu ultrahigh-pressure (UHP) terrane.
DS1992-1759
1992
Matrosova, T.I.Zyablitsev, A.Yu., Rozanov, K.I., Matrosova, T.I., GeorgiyevskayaDavidite-chevkinite association from the Central Baikal RegionDoklady Academy of Sciences USSR, Earth Science Section, Vol. 314, No. 1-6, September pp. 201-205.RussiaMineralogy, Geochemistry
DS1988-0258
1988
Matsch, C.L.Goldthwait, R.P., Matsch, C.L.Genetic classification of glacigenic deposits. Finalreport on genesis and lithology of glacial quartern.deposits of the International Union for QuaternaryResearchBalkema, 294p. $ 65.00GlobalGeomorphology, Table of contents filed
DS200612-0876
2005
Matshediso, I.B.Matshediso, I.B., Cawood, F.T.Mineral development in the SADC region: a policy perspective.Minerals & Energy - Raw Materials Report, Vol. 20, 2, June pp. 16-27.AfricaLegal
DS201201-0841
2011
Matsiak, A.Druiventak, A., Matsiak, A., Renner, J., Trepmann, C.A.Kick and cook experiments on peridotite: simulating coseismic deformation and post-seismic creep.Terra Nova, In press available,MantleGeophysics - seismics
DS1983-0589
1983
Matsiuk, S.S.Sobolev, V.K., Matsiuk, S.S.New Dat a on Titanian Pyropes in Connection with the Problem of Their Original Sources.Doklady Academy of Sciences AKAD. NAUK SSSR., Vol. 270, No. 5, PP. 1195-1198.RussiaGarnet, Mineralogy, Genesis
DS1987-0349
1987
Matsiuk, S.S.Khomenko, V.M., Matsiuk, S.S., Garanin, V.K., Kharkiv, A.D.Crystallochemical and genetic aspects of the study of clinopyroxenes from plutonic ultramafic inclusions in kimberlite #1Doklady Academy of Sciences Akademy Nauk SSSR (Russian), Vol. 296, No. 2, pp. 420-424RussiaGeochemistry, ultramafic inclusions
DS1990-0161
1990
Matsiuk, S.S.Barashkov, I.P., Matsiuk, S.S., Talnikov, S.B.First find of zonal bi-refringence garnets from the Udachnaya kimberlitepipe, Yakutia. (Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 314, No. 3, pp. 698-701RussiaGarnet mineralogy, Deposit -Udachnaya
DS1984-0495
1984
Matson, D.W.Matson, D.W.A Mass Spectrometric Investigation of Volatiles In mantle Derived amphiboles and Micas and a Raman spectroscopic Study of Silicate GlassstructuresPh.D. Thesis, University of Hawaii, Honolulu, 317pArizona, Southern AfricaMantle
DS1984-0496
1984
Matson, D.W.Matson, D.W., Muenow, D.W.Volatiles in Amphiboles from Xenoliths, Vulcans Throne, Grand Canyon, Arizona, UsaGeochimica et Cosmochimica Acta ., Vol. 48, No. 8, PP. 1629-1636.United States, Arizona, Colorado PlateauBlank
DS1986-0535
1986
Matson, D.W.Matson, D.W., Muenow, D.W., Garcia, M.O.Volatile contents of phlogopite micas from South African kimberliteContributions to Mineralogy and Petrology, Vol. 93, No. 3, pp. 399-408South AfricaPetrology
DS1900-0343
1905
Matson, G.C.Matson, G.C.Peridotite Dikes Near Ithaca, New YorkJournal of GEOLOGY, Vol. 13, PP. 264-275.United States, Appalachia, New YorkPetrography, Related Rocks
DS201312-0585
2013
Matson, J.Matson, J.What do we know about the Russian meteor. Discussion with Margaret Campbell-Brown.Scientific American, Feb. 15, 2p.RussiaMeteorite
DS1960-0071
1960
Matson, R.E.Matson, R.E.Petrography and Petrology of the Smoky Buttes Intrusives Parfield County, Montana.Msc. Thesis, Montana State University, United States, Montana, Rocky MountainsLamproite
DS1988-0479
1988
MatsudaMiyamoto, M., Matsuda, Jun-Ichi, Ito, K.Raman spectroscopy of diamond in ureilite And implications for the origin of diamondGeophysical Research Letters, Vol. 15, No. 12, pp. 1445-1448GlobalCrystallography, Meteorites
DS1998-1166
1998
MatsudaPinti, D.L., Hashuizume, MatsudaNitrogen and argon isotopes in the Archean continental crust: investigating the evolution of the early earth.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1186-7.MantleVolatiles, BIF samples - not specific to diamond
DS1987-0228
1987
Matsuda, J.Fukunaga, K., Matsuda, J., Nagao, K., Miyamoto, N., Ito, K.Noble gas enrichment in vapour growth diamonds and the origin of Diamonds in urelitesNature, Vol. 328, No. 6126, July 9, pp. 141-143GlobalMeteorites, Diamond
DS1989-0956
1989
Matsuda, J.Matsuda, J., Nagao, K.Noble gas emplacement in shock produced diamondsGeochimica et Cosmochimica Acta, Vol. 53, pp. 1117-1121GlobalDiamond Synthesis, Ureilites
DS1991-1076
1991
Matsuda, J.Matsuda, J., Fukunaga, K., Ito, K.Noble gas studies in vapor growth diamonds: comparison with shock produced diamonds and the origin of diamonds in ureilitesGeochimica et Cosmochimica Acta, Vol. 55, pp. 2011-2023GlobalSynthetic diamonds, CVD., Ureilites
DS2001-1054
2001
Matsuda, J.Seta, A., Matsumoto, T., Matsuda, J.Concurrent evolution of 3He 4He ratio in the Earth's mantle reservoir for the first 2 Ga.Earth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.211-19.MantleMineralogy
DS2002-1011
2002
Matsuda, J.Matsumoto, T., Seta, A., Matsuda, J.Helium in Archean komatiites revisited: significantly high 3He/4He ratios revisited by fractional crushingEarth and Planetary Science Letters, Vol.196,3-4,pp. 213-25.GlobalKomatiites
DS1995-1179
1995
Matsuda, J.I.Matsuda, J.I., Kasumi, A., Yajima, H.Noble gas studies in diamond synthesized shock loading in laboratory And implications on origin in ureilites.Geochim. Cosmochimica Acta, Vol. 59, No. 23, Dec. 1, pp. 4939-4950.GlobalUreilites
DS1998-0713
1998
Matsuda, J.I.Kamijo, K., Hashizume, K., Matsuda, J.I.Noble gas constraints on the evolution of the atmosphere mantle systemGeochimica et Cosmochimica Acta, Vol. 62, No. 13, July pp. 2311-22.MantleDegassing, helium
DS1998-1557
1998
Matsuda, J.I.Wada, N., Matsuda, J.I.A noble gas study of cubic diamonds from Zaire: constraints on their mantlesource.Geochimica et Cosmochimica Acta, Vol. 62, No. 13, July pp. 2335-46.GlobalGeochemistry, Cubic diamonds
DS2002-1010
2002
Matsuda, J-I.Matsumoto, T., Pinti, D.L., Matsuda, J-I., Umino, S.Recycled noble gas and nitrogen in the subcontinental lithospheric mantle: implications for N He Ar in fluid inclusions of SE Australian xenoliths.Geochemical Journal, Vol. 36, pp.209-17.AustraliaGeochronology - xenoliths, Newer volcanics
DS200612-0880
2006
Matsuda, J-I.Matsumoto, T., Maruoka, T., Matsuda, J-I., Shimoda, G., Yamamoto, K., Morishita, T., Arai, S.Isotopic compositions of noble gas and carbon in the Archean carbonatites from the Sillinjarvi mine, central Finland.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 21, abstract only.Europe, FinlandCarbonatite, geochronology
DS201312-0625
2012
Matsuda, J-I.Nagashima, K., Nara, M., Matsuda,J-I.Raman spectroscopic study of diamond and graphite in ureilites and the origin of diamonds.Meteorites and Planetary Science, Vol. 47, 11, pp. 1728-1737. (thanks Grant)TechnologyUrelilite
DS1975-0803
1978
Matsuda, K.Matsuda, K.Kimberlites and Diamond Deposits: a Review from a Standpoint of a Prospector.Tokyo Geographical Soc. Journal of Geography, Vol. 87, No. 1, MO. 823, PP. 27-44.GlobalBlank
DS200612-1391
2006
Matsufuji, K.Sumino, H., Kaneoka, I., Matsufuji, K., Sobolev, A.V.Deep mantle origin of kimberlite magmas revealed by neon isotopes.Geophysical Research Letters, Vol. 33, L1618Russia, SiberiaGeochemistry - noble gases Udachnaya, MORB
DS200612-1392
2006
Matsufuji, K.Sumino, H., Kaneoka, I., Matsufuji, K., Sobolev, A.V.Deep mantle origin of kimberlite magmas revealed by neon isotopes.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 624. abstract only.Russia, YakutiaGeochronology
DS1991-1077
1991
Matsui, M.Matsui, M., Price, G.D.Simulation of the pre-melting behaviour of MgSiO3 perovskite at high pressures and temperaturesNature, Vol. 351, June 27, pp. 735-737GlobalMantle, Silicate perovskite
DS2000-0631
2000
Matsui, M.Matsui, M.Molecular dynamics of MgSiO3 perovskite and the 660 km seismic discontinuiPhysical Earth and Planetary Interiors, Vol. 121, No.1-2, Sept. pp.77-84.MantleGeophysics - seismics, MOHO
DS2000-0632
2000
Matsui, M.Matsui, M.Molecular dynamics simulation of perovskite and 660 km seismic discontinuitPhysical Earth and Planetary Interiors, Vol. 121, No. 1-2, pp.77-84.MantlePerovskites, Discontinuity
DS2001-0738
2001
Matsui, M.Matsui, M.Density and bulk sound velocity jumps across the 660 km seismic discontinuityPhysics of the Earth and Planetary Interiors, Vol. 125, No. 1-4, pp. 141-6.MantleGeophysics - seismics
DS201412-0355
2014
Matsui, M.Higo, Y., Matsui, M., Irifune, T.Development of ultrasonic measurement technique under lower mantle conditions.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 1p. AbstractTechnologyPerovskite
DS1993-1567
1993
Matsui, T.Tajika, E., Matsui, T.Degassing history anbd carbon cycle of the earth: from an impact-induced steam atmosphere to the present atmosphereLithos, Vol. 30, No. 3-4, September pp. 267-280MantleCarbon cycle, Degassing atmosphere
DS201212-0800
2012
Matsui, T.Yamamoto, H., Terabayashi, M., Okura, H., Matsui, T., Kanedo, Y.Northward extrusion of the ultrahigh-pressure units in the southern Dabie metamorphic belt, east-central China.Island Arc, in press availableChinaUHP
DS1991-1356
1991
Matsuk, S.S.Platonov, A.N., Langer, K., Matsuk, S.S., Taran, M.N., Hu, X.iron 2 Ti4 Charge transfer in garnets from mantle eclogitesEuropean Journal of Mineralogy, Vol. 3, No. 1, pp. 19-26GlobalMineralogy, Eclogites -garnet
DS200612-0914
2006
MatsukageMibe, K., Kanzaki, Kawamoto, Matsukage, Fei, OnoSecond critical end point and properties of aequeous fluid in a hydrous upper mantle.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p. 132.MantleMagmatism
DS1998-0037
1998
Matsukage, K.Arai, S., Matsukage, K.Petrology of chromitite micropod Hess Deep: comparison between abyssal -alpine type podiform chromititesLithos, Vol. 43, No. 1, May pp. 1-14GlobalMagma, mantle, supra-subduction
DS201610-1880
2016
Matsukage, K.Kondo, N., Yoshino, T., Matsukage, K., Kogiso, T.Major element composition in an early enriched reservoir: constarints from 142 Nd/144 Nd isotope systematics in the earth Earth and high pressure melting experiments of a primitive peridotite,Progress in Earth and Planetary Science, Vol. 3, 25, Aug. 22MantleExperimental petrology

Abstract: The Accessible Silicate Earth (ASE) has a higher 142Nd/144Nd ratio than most chondrites. Thus, if the Earth is assumed to have formed from these chondrites, a complement low-142Nd/144Nd reservoir is needed. Such a low-142Nd/144Nd reservoir is believed to have been derived from a melt in the early Earth and is called the Early Enriched Reservoir (EER). Although the major element composition of the EER is crucial for estimating its chemical and physical properties (e.g., density) and is also essential for understanding the origin and fate of the EER, which are both major factors that determine the present composition of the Earth, it has not yet been robustly established. In order to determine the major element composition of the EER, we estimated the age and pressure-temperature conditions to form the EER that would best explain its Nd isotopic characteristics, based on Sm-Nd partitioning and its dependence on pressure, temperature, and melting phase relations. Our estimate indicates that the EER formed within 33.5 Myr of Solar System formation and at near-solidus temperatures and shallow upper-mantle pressures. We then performed high-pressure melting experiments on primitive peridotite to determine the major element composition of the EER at estimated temperature at 7 GPa and calculated the density of the EER. The result of our experiments indicates that the near-solidus melt is iron-rich komatiite. The estimated density of the near-solidus melt is lower than that of the primitive peridotite, suggesting that the EER melt would have ascended in the mantle to form an early crust. Given that high mantle potential temperatures are assumed to have existed in the Hadean, it follows that the EER melt was generated at high pressure and, therefore, its composition would have been picritic to komatiitic. As the formation age of the EER estimated in our study precedes the last giant, lunar-forming impact, the picritic to komatiitic crust (EER) would most likely have been ejected from the Earth by the last giant impact or preceding impacts. Thus, the EER has been lost, leaving the Earth more depleted than its original composition.
DS200612-0877
2005
Matsukage, K.N.Matsukage, K.N., Jing, Z., Karato, S.Density of hydrous silicate melt at the conditions of Earth's deep upper mantle.Nature, No. 7067, Nov. 24, pp. 488-491.MantleGeochemistry
DS200612-0878
2005
Matsukage, K.N.Matsukage, K.N., Nishihara, Y., Karato, S-i.Seismological signature of chemical differentiation of Earth's upper mantle.Journal of Geophysical Research, Vol. 110, B12, B 12305 10.1029/2004 JB003504MantleGeophysics - seismics
DS200712-0985
2006
Matsukage, K.N.Shito, A., Karato, S., Matsukage, K.N., Nishihara, Y.Towards mapping the three dimensional distribution of water in the upper mantle from velocity and attenuation tomography.American Geophysical Union, Geophysical Monograph, No. 168, pp. 225-236.MantleTomography
DS201605-0881
2016
Matsukage, K.N.Nishihara, Yu., Matsukage, K.N.Iron-titanium oxyhydroxides as water carriers in the Earth's deep mantle.American Mineralogist, Vol. 101, pp. 919-927.MantleWater - transition zone
DS1960-0769
1966
Matsumoto, H.Yagi, K., Matsumoto, H.Note on the Leucite Bearing Rocks from the Leucite Hills, Wyoming.Journal of FACULTY SCI. HOKKAIDO University SER. 4, GEOL. MIN., Vol. 13, No. 3, PP. 301-315.GlobalLeucite Hills, Leucite, Rocky Mountains
DS1998-0962
1998
Matsumoto, I.Matsumoto, I., et al.Chemical composition of chromian spinel as a guide to genesis - prospect of chromitite in harzburgite mantleGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Abstract Volume, p. A120. abstract.JapanHarzburgite
DS2001-0739
2001
Matsumoto, I.Matsumoto, I., Arai, S.Morphological and chemical variations of chromian spinel in dunite harzburgite complexes from Sangun ZoneMineralogy and Petrology, Vol. 73, No. 4, pp. 305-24.JapanMantle melt reaction, Chromitite formation - not specific to diamonds
DS1990-0894
1990
Matsumoto, K.Kurosawa, M., Yurimoto, H., Sueno, S., Matsumoto, K.Hydrogen distribution in San Carlos olivine #1Eos, Vol. 71, No. 28, July 10, p. 903. AbstractNew MexicoMantle, San Carlos olivine
DS200612-0879
2006
Matsumoto, N.Matsumoto, N., Namiki, A., Sumita, I.Influence of a basal thermal anomaly on mantle convection.Physics of the Earth and Planetary Interiors, in press availableMantleGeothermometry, mantle convection, hot spot, melting
DS1998-0963
1998
Matsumoto, T.Matsumoto, T., Honda, M., McDougall, O'Reilly, S.Y.Noble gases in an anhydrous lherzolites from the Newer Volcanics, southeastern Australia: Mid Ocean Ridge Basalt (MORB) like...Geochimica et Cosmochimica Acta, Vol. 62, No. 14, July, pp. 2521-34.AustraliaMantle - subcontinental, Geochemistry
DS2000-0633
2000
Matsumoto, T.Matsumoto, T., Honda, M., Yaxley, G.Noble gases in pyroxenites and metasomatised peridotites from Newer Volcanics, Mantle MetasomatismChemical Geology, Vol. 168, No. 1-2, July 1, pp. 49-74.Australia, SoutheastMetasomatism, Geochemistry
DS2001-1054
2001
Matsumoto, T.Seta, A., Matsumoto, T., Matsuda, J.Concurrent evolution of 3He 4He ratio in the Earth's mantle reservoir for the first 2 Ga.Earth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.211-19.MantleMineralogy
DS2002-1010
2002
Matsumoto, T.Matsumoto, T., Pinti, D.L., Matsuda, J-I., Umino, S.Recycled noble gas and nitrogen in the subcontinental lithospheric mantle: implications for N He Ar in fluid inclusions of SE Australian xenoliths.Geochemical Journal, Vol. 36, pp.209-17.AustraliaGeochronology - xenoliths, Newer volcanics
DS2002-1011
2002
Matsumoto, T.Matsumoto, T., Seta, A., Matsuda, J.Helium in Archean komatiites revisited: significantly high 3He/4He ratios revisited by fractional crushingEarth and Planetary Science Letters, Vol.196,3-4,pp. 213-25.GlobalKomatiites
DS200412-1436
2004
Matsumoto, T.Nishio, Y., Nakai, S., Yamamoto, J., Sumino, H., Matsumoto, T., Prikhodko, V.S., Arai, S.Lithium isotopic systematics of the mantle derived ultramafic xenoliths: implications for EMI origin.Earth and Planetary Science Letters, Vol. 217, 3, Jan. 15, pp. 245-261.MantleGeochronology
DS200612-0880
2006
Matsumoto, T.Matsumoto, T., Maruoka, T., Matsuda, J-I., Shimoda, G., Yamamoto, K., Morishita, T., Arai, S.Isotopic compositions of noble gas and carbon in the Archean carbonatites from the Sillinjarvi mine, central Finland.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 21, abstract only.Europe, FinlandCarbonatite, geochronology
DS201012-0284
2010
Matsumoto, T.Honda, M., Phillips, D., Harris, J., Matsumoto, T.Distinct neon isotope compositions found in polycrystalline diamonds and framesites from the Jwaneng kimberlite pipe, Botswana.Goldschmidt 2010 abstracts, abstractAfrica, BotswanaGeochronology
DS201112-0447
2011
Matsumoto, T.Honda, M., Phillips, D., Harris, J.W., Matsumoto, T.He, Ne and Ar in peridotitic and eclogitic paragenesis diamonds from the Jwaneng kimberlite, Botswana - implications for mantle evolution and diamond formation ages.Earth and Planetary Science Letters, Vol. 301, 1-2, pp. 43-51.Africa, BotswanaGeocheonology - Jwaneng
DS1986-0591
1986
Matsumoto, Y.Nago, T., Matsumoto, Y., et al.Cenozoic minette from Kawamoto district, Shimane prefecture SouthwestJapan.*JAPGanseki Kobutsu Kosho Gakki-Shi, *JAP, Vol. 81, No. 10, pp. 423-426JapanPetrology, Minette
DS1975-0121
1975
Matsuo, S.Kuroda, Y., Suzuoki, T., Matsuo, S., Aoki, K.I.D/h Ratios of the Coexisting Phlogopite Richterite from Mica Nodules and a Peridotite in South African Kimberlites.Contributions to Mineralogy and Petrology, Vol. 52, No. 4, PP. 315-318.South AfricaMineral Chemistry, Hydrogen
DS200812-1148
2008
Matsushima, M.Takahashi, F., Tsunakawa, H., Matsushima, M., Mochizuki, N., Honkura, Y.Effects of thermally homogeneous structure in the lowermost mantle on the geomagnetic field strength.Earth and Planetary Science Letters, Vol. 272, 3-4, pp. 738-746.MantleGeothermometry
DS200912-0817
2009
Matsuyk, S.Wirth, R., Kaminsky, F., Matsuyk, S.New and unusual mineral assemblages discovered in diamond from Juina, Brazil using FIB/TEM.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlySouth America, BrazilDeposit - Juina
DS1987-0445
1987
Matsuyk, S.S.Matsuyk, S.S., Khomenko, V.M., Slodkevich, V.V., Garanin, V.K.The genesis of diamond bearing rocks of kimberlite basic structures and theMineral. Sbornik (L'Vov), (Russian), Vol. 41, No. 1, pp. 18-24RussiaAfrica, Beni Bouchera, Diamond
DS200812-1299
2008
Matsuzaki, T.Yoshina, T., Manthilake, G., Matsuzaki, T., Katsura, T.Dry mantle transition zone inferred from the conductivity of wadsleyite and ringwoodite.Nature, Vol. 451, 7176, pp. 326-329.MantleGeochemistry
DS201012-0347
2009
Matsuzaki, T.Katsura, T., Yoshino, T., Manthilake, G., Matsuzaki, T.Electrical conductivity of the major upper mantle minerals: a review.Russian Geology and Geophysics, Vol. 50, 12, pp. 1139-1145.MantleGeophysics - seismics
DS201212-0811
2012
Matsuzaki, T.Zhang, B., Yoshino, T., Wu, X., Matsuzaki, T., Shan, S., Katsura, T.Electrical conductivity of enstatite as a function of water content: implications for the electrical structure in the upper mantle.Earth and Planetary Science Letters, Vol. 357-358, pp. 11-20.MantleHT Hp hydrous conditions
DS201212-0171
2012
Matsyiak, A.Druiventak, A., Matsyiak, A., Renner, J., Trepmann, C.Kick and cook experiments on peridotite: simulating coseismic deformation post-seismic creep.Terra Nova, Vol. 24, 1, pp. 62-69.MantleGeophysics - seismics
DS1986-0094
1986
MatsyukBotkunov, A.I., Garanin, V.K., Krot, A.N., Kudryavtseva, G.P., MatsyukPrimary hydrocarbon inclusions in garnets from the Mir and Sputnikkimberlite pipesDoklady Academy of Science USSR, Earth Science Section, Vol. 280, No. 1-6, October pp. 136-141RussiaMineralogy, Garnet
DS200512-1189
2005
Matsyuk, S.Wirth, R., Matsyuk, S.Nanocrystalline (Mg Fe Cr) TiO3 perovskite inclusions in olivine from a mantle xenolith, Udachnaya East kimberlite pipe, Siberia.Physics and Planetary Science Letters, Vol. 233, 3-4, pp. 325-336.Russia, SiberiaMineral chemistry - inclusions
DS200512-1190
2005
Matsyuk, S.Wirth, R., Matsyuk, S.Nanocrystalline (Mg Fe Cr TiO2 perovskite inclusions in olivine from a mantle xenolith, Udachnaya east kimberlite pipe, Siberia.Earth and Planetary Science Letters, Vol. 233, 3-4, May 15, pp. 325-336.Russia, Yakutia, SiberiaWostotschnaya, TEM, HREM, ilmenite
DS200712-1170
2007
Matsyuk, S.Wirth, R., Vollmer, C., Brenker, F., Matsyuk, S., Kaminsky, F.Inclusions of nanocrystalline hydrous aluminum silicate 'phase egg' in superdeep diamonds from Juin a ( Mato Grosso State, Brazil).Earth and Planetary Science Letters, Vol. 259, 3-4, pp. 384-399.South America, Brazil, Mato GrossoDiamond - mineralogy
DS200712-1171
2007
Matsyuk, S.Wirth, R., Vollmer, C., Brenker, F., Matsyuk, S., Kaminsky, F.Inclusions of nanocrystalline hydrous aluminum silicate 'phase egg' in superdeep diamonds from Juin a ( Mato Grosso State, Brazil).Earth and Planetary Science Letters, Vol. 259, 3-4, pp. 384-399.South America, Brazil, Mato GrossoDiamond - mineralogy
DS200812-0564
2008
Matsyuk, S.Khisina, N., Wirth, R., Matsyuk, S., Koch0Mueller, M.Microstructural features and OH bearing nanoinclusions in 'wet' olivine from mantle nodules in kimberlites.European Journal of Mineralogy, Vol. 20, 6. pp. 1067-1078.MantleNodule - petrology
DS200912-0353
2009
Matsyuk, S.Kaminsky, F., Wirth, R., Matsyuk, S.Carbonate, halide and other new mineral inclusions in diamond and deep seated carbonatitic magmas.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlySouth America, BrazilDeposit - Juina
DS200912-0354
2009
Matsyuk, S.Kaminsky, F., Wirth, R., Matsyuk, S.Carbonate and halide inclusions in diamond and deep seated carbonatitic magma.Goldschmidt Conference 2009, p. A618 Abstract.MantleSubduction
DS200912-0373
2008
Matsyuk, S.Khisina, N., Wirth, R., Matsyuk, S., Koch-Mueller, M.Microstructural features and OH bearing nanoinclusions in 'wet' olivine from mantle nodules in kimberlites.European Journal of Mineralogy, Vol. 20, 6,Africa, South AfricaOlivine
DS200912-0818
2009
Matsyuk, S.Wirth, R., Kaminsky, F., Matsyuk, S., Schrieber, A.Unusual micro and nano inclusions in diamonds from the Juin a area, Brazil.Earth and Planetary Science Letters, Vol. 286, 1-2, pp. 292-303.South America, BrazilDeposit - Juina
DS201012-0339
2009
Matsyuk, S.Kaminsky, F., Wirth, R., Matsyuk, S., Schreiber, A., Thomas, R.Nyerereite and nahcolite inclusions in diamond: evidence for lower mantle carbonatitic magmas.Mineralogical Magazine, Vol. 73, 3, Oct. pp. 797-816.South America, BrazilJuina area - carbonatite
DS1980-0224
1980
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.A., Kharkiv, A.D.Color As a Crystallochemical Indicator for Garnets of Deep Seated Mineral Associations.Mineraloicheskii Zhurnal, Vol. 2, No. 4, PP. 27-47.RussiaMineralogy
DS1980-0225
1980
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.A., Kharkiv, A.D.The Typomorphic Significance of Color in Garnets from Deep Seated Mineral Associations.Mineraloicheskii Zhurnal, Vol. 2, No. 5, PP. 12-25.RussiaMineralogy
DS1981-0288
1981
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.N., Khar'kiv, A.D.(the Genesis of Garnets in Kimberlite Pipes in Yakutia, According to Optical Spectroscopy Data.)Mineral. Zhur., Vol. 3, No. 1, PP. 37-47.RussiaKimberlite
DS1982-0328
1982
Matsyuk, S.S.Khomenko, V.M., Platonov, A.N., Matsyuk, S.S., Kharkiv, A.D.Colouring and Pleochroism of Clino-pyroxenes from Deep Inclusions in Mir Pipe Kimberlites.Mineral. Zhurn., No. 4, PT. 1, PP. 41-51.RussiaPetrography
DS1982-0411
1982
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.N., Ponomarenko, A.I., Kharkiv, A.D.Color of Garnet As Criterion of Presence of Diamond in Eclogitic Paragenesis of Kimberlite Pipes.Zap. Vses. Mineral. Obshch., Vol. 111, No. 2, PP. 159-166.RussiaBlank
DS1984-0298
1984
Matsyuk, S.S.Gerasimov, A.YU., Povaremnykh, A.S., Matsyuk, S.S., Kharkiv, A.Hardness of Chromium Containing Garnets from KimberlitesMineral. Zhur., Vol. 6, No. 2, PP. 42-50.RussiaMineralogy
DS1984-0299
1984
Matsyuk, S.S.Gerasimov, A.YU., Povarennykh, S.S., Matsyuk, S.S., Kharkiv, A.The Hardness of Chromium Bearing Garnets from KimberlitesMineral. Zhurn., Vol. 6, No. 2, PP. 42-50.RussiaBlank
DS1985-0420
1985
Matsyuk, S.S.Matsyuk, S.S., Kryukov, A.V., et al.A Comparative Study of the Composition and Properties of Garnets from The alkali Basalt Pipes of the Minusinsk Basin And kimberlites of Yakutia.(russian)Mineral. Zhurn., (Russian), Vol. 7, No. 4, pp. 18-29RussiaPyrope, Analyses
DS1985-0421
1985
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.N., Khomenko, V.M.Optical Spectra and Color of Mantle Minerals in KimberlitesNaukova Dumka, Kiev, 248P.RussiaKimberlite, Mantle, Mineral Spectra
DS1985-0422
1985
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.N., Khomenko, V.M.Optical Spectra and the Tinting of Mantle Minerals in Kimberlite.(russian)Izd. Nauka Dumka, UKR, SSR, (Russian), 248pRussia, South AfricaPetrology, Mineral Chemistry
DS1985-0769
1985
Matsyuk, S.S.Zinchuk, N.N., Melnik, YU.M., Matsyuk, S.S., et al.Anhydrous Sulfates from the Kimberlites of Yakutia. (russian)Mineral. Sbornik., (Russian), Vol. 39, No. 2, pp. 33-40RussiaBlank
DS1986-0262
1986
Matsyuk, S.S.Garanin, V.K., Kudryavtseva, G.P., Matsyuk, S.S., Cherenkova, A.F.Deep seated mineral associations of kimberlites from the SouthWestern periphery of the Anabar massif.(Russian)Mineral Zhurn., (Russian), Vol. 8, No. 4, pp. 20-32RussiaPetrology, Mineralogy
DS1987-0070
1987
Matsyuk, S.S.Botkunov, A.I., Matsyuk, S.S., PLatonov, A.N.Distribution of paragenetic types of garnets in kimberlite rocks from a horizon of the Mir pipe; from optical spectra and colorimetry data.(Russian)Geol. Zhurnal, (Russian), Vol. 47, No. 1, pp. 124-132RussiaBlank
DS1987-0344
1987
Matsyuk, S.S.Kharkiv, A.D., Matsyuk, S.S., Safronov, A.F., Makhoto, V.F.Minerals in xenoliths of deep seated rocks from kimberlites oftheInternationial'Naya' pipe, Yakutia.(Russian)Mineral. Zhurn., *UKR., Vol. 9, No. 4, pp. 62-71RussiaBlank
DS1987-0348
1987
Matsyuk, S.S.Khomemko, V.M., Matsyuk, S.S., Garanin, V.K., Kharkiv, A.D.Crystallochemical and genetic aspects of the study of clinopyroxenes from mantle peridotite nodules in kimberlites.(Russian)Doklady Academy of Science USSR, Earth Science Section, Vol. 296, No. 5, Sept-Oct., pp. 132-135RussiaGeochemistry, Kimberlite - inclusions
DS1987-0446
1987
Matsyuk, S.S.Matsyuk, S.S., Vishnevskii, A.A., Platonov, A.N., Kharkiv, A.D.Composition and optical spectroscopic characteristics of garnets from peridotites-pyroxenite intrusives of the Czech Massif.(Russian)Mineral. Zhurn., (Russian), Vol. 9, No. 3, pp. 15-28GlobalBlank
DS1987-0581
1987
Matsyuk, S.S.Platanov, A.N., Botkunov, A.I., Matsyuk, S.S.Distribution of paragenetic types of garnets in kimberlitic rocks from a horizon of the Mir pipe (based on optical spectroscopic colorimetric data).Geol. Zhurn. (Russian), Vol. 47, No. 1, pp. 124-132RussiaBlank
DS1988-0351
1988
Matsyuk, S.S.Kharkiv, A.D., Matsyuk, S.S., Safronov, A.F.Mineralogy of deep seated xenolithic rocks From kimberlites of the Aikhal pipe (western Yakutia) USSR. (Russian)Mineral Zhurn.(Russian), Vol. 42, No. 1, pp. 20-30RussiaKimberlite, Mineralogy
DS1988-0352
1988
Matsyuk, S.S.Kharkiv, A.D., Matsyuk, S.S., Safronov, A.F.Mineralogy of deep seated xenoliths from the Aykalkimberlite pipe, Western Yakutia.(Russian)Mineral. Sbornik (L'Vov), (Russian), Vol. 42, No. 1, pp. 20-30RussiaPetrology, Deposit -Aykal
DS1988-0445
1988
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.N., Taran, M.N., Nazarov, Yu.N., Dunaeva, G.V.Optical spectroscopy as an effective investigative method when prospecting for kimberlites.*UKR.Visn. Akad. Nauk UKR. RSR, *UKR., No. 2, pp. 53-59RussiaBlank
DS1988-0629
1988
Matsyuk, S.S.Shabalin, B.G., Matsyuk, S.S.IR spectroscopic study of characteristics of isomorphism of R(2+ )cations in garnets of eclogite paragenesis from kimberlites. (Russian)Ontogeniya Mineralov I Teknol Mineral Kiev.(Russian), pp. 176-182RussiaEclogite, Spectroscopy
DS1989-0772
1989
Matsyuk, S.S.Khomenko, V.M., Matsyuk, S.S., Garanin, V.K., Kharkiv, A.D.Crystallochemical and genetic aspects of the study of clinopyroxenes from plutonic ultramafic inclusions In kimberlite #2Doklady Academy of Science USSR, Earth Science Section, Vol. 296, No. 1-6, pp. 132-135RussiaCrystallography, Ultramafic inclusions
DS1989-0957
1989
Matsyuk, S.S.Matsyuk, S.S., Platonov, A.N., Bulanova, G.P.Optical spectra of orange garnets included in diamonds. (Russian)Doklady Academy of Sciences Nauk. SSR, Ser. B., Geol. Khim Biol, (Russian), No. 5, pp. 15-18RussiaDiamond inclusion, Garnet analyses
DS1989-0958
1989
Matsyuk, S.S.Matsyuk, S.S., Platonov, O.M., Bulanova, G.P.Optical spectra of orange garnet inclusions in diamonds.(Russian)Dopov. Akad. Nauk. Ukr. Ser. B., (Russian), No. 5, pp. 14-17RussiaDiamond morphology, Garnet inclusions
DS1990-0518
1990
Matsyuk, S.S.Garanin, V.K., Kudryavtseva, G.P., Matsyuk, S.S., Cherenkova, A.F., CherenkovDiscovery of zircon bearing ilmenite-amphibole-pyroxenite in kimberlitesInternational Geology Review, Vol. 32, No. 11, November pp. 1086-1094RussiaPyroxenite- zircon, Geochemistry
DS1990-0996
1990
Matsyuk, S.S.Matsyuk, S.S., Bulanova, G.P., Platonov, A.N.Optical spectroscopic investigation of mineral inclusions from diamond and some problems of their genesis.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 1, pp. 3-14RussiaDiamond inclusions, Mineralogy
DS1990-1604
1990
Matsyuk, S.S.Yakovlev, B.G., Matsyuk, S.S., Vishnevskiy, A.A., Chubarov, V.M.Evolution of mineral equilibration temperatures and petrogenesis of the deep mafic ferruginous granulites from Yakutian kimberlite pipes.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 4, August pp. 3-15RussiaPetrology, Mineral chemistry
DS1991-0067
1991
Matsyuk, S.S.Bao Yannan, Matsyuk, S.S.Characteristics of chemical composition of spinels from kimberlites of the Shandong and Liaoning Provinces, China. (Russian)Geochemistry International (Geokhimiya), (Russian), Vol. 1991, No. 2, pp. 259-266ChinaGeochemistry, Spinels
DS1991-0068
1991
Matsyuk, S.S.Bao, J.N., Matsyuk, S.S., Vishnevskaya, A.A.Garnets from Chin a kimberlites (technical note).(Russian)Izvest. Akad. Nauk SSSR, (Russian), No. 8, August pp. 152-157ChinaPetrology, Garnets
DS1991-0069
1991
Matsyuk, S.S.Bao, Y.N., Matsyuk, S.S.Pecularieties of chemical composition of spinels from kimberlites of Shantung and Liaoning Province, China.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 2, Feb. pp. 259-266ChinaGeochemistry, Spinels
DS1991-1902
1991
Matsyuk, S.S.Yannan Bao, Matsyuk, S.S.Composition of kimberlite spinels from Shangtung and Liaoning Provinces inChinaGeochemistry International, Vol. 28, No. 9, pp. 89-95ChinaGeochemistry, kimberlite spinels
DS1992-0081
1992
Matsyuk, S.S.Barashkov, Yu.P., Matsyuk, S.S., Talnikova, S.B.First find of garnet with zoned birefringence in material from the Udachnaya kimberlite pipe, YakutiaDoklady Academy of Sciences USSR, Earth Science Section, Vol. 314, No. 1-6, July 1992, pp. 198-200Russia, YakutiaGarnet, Mineralogy
DS1992-1011
1992
Matsyuk, S.S.Matsyuk, S.S., Vishnevskii, A.A., Cherenkova, A.F., Egorova, L.N.K-richterite bearing ilmenite clinohumite dunites: a new variety of Deep seated peridotites in kimberlites.Soviet Geology and Geophysics, Vol. 32, No. 12, pp. 64-70.Russia, SayanGeochemistry, mineral chemistry, Peridotite xenoliths
DS1998-0964
1998
Matsyuk, S.S.Matsyuk, S.S., Kharkiv, A.D.The first find of pyrope and titanoclinohumite clinopyroxene assemblage inkimberlites.Doklady Academy of Sciences, Vol. 359A, No. 3, Mar-Apr. pp. 341-3.RussiaMineralogy - garnet
DS1998-0965
1998
Matsyuk, S.S.Matsyuk, S.S., Langer, K., Hosch, A.Hydroxyl defects in garnets from mantle xenoliths in kimberlites of the Siberian Platform #2Contributions to Mineralogy and Petrology, Vol. 132, No. 2, pp. 163-179.Russia, SiberiaMantle xenoliths, Petrology
DS1998-0966
1998
Matsyuk, S.S.Matsyuk, S.S., Langer, K., Hosch, A.Hydroxyl defects in garnets from mantle xenoliths in kimberlites of the Siberian Platform #1Contributions to Mineralogy and Petrology, Vol. 133, No. 4, pp. 418-.Russia, SiberiaXenoliths, Garnets
DS200412-1023
2004
Matsyuk, S.S.Koch Muller, M., Matsyuk, S.S., Wirth, R.Hydroxyl in omphacites and omphacitic clinopyroxenes of upper mantle to lower crustal origin beneath the Siberian platform.American Mineralogist, Vol.89, 7, pp. 921-931.Russia, SiberiaMineralogy, Mir, Zagadochnaya, Udachnaya
DS200412-1025
2004
Matsyuk, S.S.Koch-Muller, M., Matsyuk, S.S., Wirth, R.Hydroxyl in omphacites and omphacitic clinopyroxenes of upper mantle to lower crustal origin beneath the Siberian Platform.American Mineralogist, Vol. 89, June pp. 921-931.Russia, YakutiaSpectroscopy, Mir, Zagadochnaya, Udachnaya pipes
DS200412-1247
2004
Matsyuk, S.S.Matsyuk, S.S., Langer, K.Hydroxl in olivines from mantle xenoliths in kimberlites of the Siberian platform.Contributions to Mineralogy and Petrology, Vol. 147, 4, pp. 413-437.Russia, SiberiaMineral chemistry
DS200612-0717
2006
Matsyuk, S.S.Koch-Mueller, M., Matsyuk, S.S., Rhede, D., Wirth, R., Khistina, N.Hydroxyl in mantle olivine xenocrysts from the Udachnaya kimberlite pipe.Physics and Chemistry of Minerals, Vol. 33, 4, pp. 276-287.RussiaMineral chemistry - Udachnaya
DS202005-0743
2020
Matsyuk, S.S.Kostrovitsky, S.I., Yakolev, D.A., Soltys, A., Ivanov, A.S., Matsyuk, S.S., Robles-Cruz, S.E.A genetic relationship between magnesian ilmenite and kimberlites of the Yakutian diamond fields.Ore Geology Reviews, Vol. 120, 16p. PdfRussia, Yakutiailmenite

Abstract: We present new major element geochemical data, and review the existing data for ilmenite macrocrysts, megacrysts, as well as ilmenite in mantle xenoliths from four diamondiferous kimberlite fields in the Yakutian province. This combined data set includes 10,874 analyses of ilmenite from 94 kimberlite pipes. In the studied samples we identify various different ilmenite compositional distributions (e.g., “Haggerty's parabola”, or “Step-like” trends in MgO-Cr2O3 bivariate space), which are common to all kimberlites from a given cluster, but the compositional distributions differ between clusters. We propose three stages of ilmenite crystallization: 1) Mg-Cr poor ilmenite crystallising from a primitive asthenospheric melt (the base of Haggerty's parabola on MgO-Cr2O3 plots). 2) This primitive asthenospheric melt was then modified by the partial assimilation of lithospheric material, which enriched the melt in MgO and Cr2O3 (left branch of Haggerty’s parabola). 3) Ilmenite subsequently underwent sub-solidus recrystallization in the presence of an evolved kimberlite melt under increasing oxygen fugacity (ƒO2) conditions (right branch of Haggerty’s parabola in MgO-Cr2O3 plots). Significant differences in the ilmenite compositional distribution between different kimberlite fields are the result of diverse conditions during subsequent ilmenite crystallization in a kimberlite melt ascending through the lithospheric mantle, which have different textures and compositions beneath the studied kimberlite fields. We propose that a TiO2 fluid formed due to immiscibility of an asthenospheric melt with low Cr and high Ti contents. This fluid infiltrated lithospheric mantle rocks forming Mg-ilmenite. These features indicate a genetic link between ilmenite and the host kimberlite melt.
DS1985-0354
1985
Matsyukm, S.S.Komenko, V.M., Platanov, A.N., Matsyukm, S.S.The optical sprectoscopy of chromium isomorphism in enstatite from plutonic paragenesisGeochemistry International, Vol. 21, No. 6, pp. 47-53Russia, YakutiaPetrology
DS2001-0740
2001
Matte, P.Matte, P.The Variscan collage and orogeny (480-290 Ma) and the tectonic definition of Armorica microplate: a reviewTerra Nova, Vol. 13, pp. 122-18.EuropeTectonics
DS201906-1321
2019
Matte, S.Matte, S., Stevenson, R., Constantin, M.Metallogeny, mineralogy and isotopic geochemistry of the Kipawa rare earth deposit: genetic implications and comparison with other rare earth deposits in peralkaline syenites.GAC/MAC annual Meeting, 1p. Abstract p. 140.Canada, Quebecdeposit - Kipawa

Abstract: We propose to study the Kipawa peralkaline complex, a rare-earth deposit principally composed of eudialyte, mosandrite and britholite. The Kipawa complex is situated in the Parautochton zone of the Grenville Province in the Tesmiscamingue region of Quebec, 55 km south of contact with Superior Province. The complex consists of peralkaline syenites, amphibolites, gneisses that are intercalated with calc-silicate rocks and marble, and overlain by a peralkaline gneissic granite. The Kipawa complex differs geochemically and petrologically from other well-known peralkaline complexes such as the Illimausaq, Lovozero, Thor Lake or Strange Lake complexes. Classic peralkaline complexes are large, circular igneous complexes, with or without volcanism and have an isotopic signature reflecting mantle origin with different degrees of assimilation and crustal contamination (for example Illimausaq is reported with ?Nd values of 0.4 and -5.7). The Kipawa Complex is a thin, folded stack of sheet imbricates between Kikwissi Suite rocks, McKillop Lake sequence and Red Pine Chute gneiss, suggesting a regional tectonic control. Isotopic analyses carried out by other teamsindicate a strong crustal signature (?Nd = -8.7). Several hypotheses are possible: crustal contamination, hydrothermal activity, fluids alteration during formation, metamorphism or dominant crustal origin. Our objective is to characterize the geochemical and isotopic composition of the Kipawa complex in order to improve our understanding of the age and formation of the complex. Analyses of both whole rocks, eudialytes and zircons will be made to obtain isotopic signatures and determine formation ages and/or post-formation processes.
DS202106-0926
2021
Mattei, M.Casalini, M., Avanzinelli, R., Tommasini, S., Natali, C., Bianchini, G., Prelevic, D., Mattei, M., Conticelli, S.Petrogenesis of Mediterranean lamproites and associated metasomatic events in the postcollisional lithospheric upper mantle.Geological Society, London Special Publication, doi.org/10.1144/SP513-2021-36 49p. PdfEurope, Italy, France, Spain, Serbia, Macedonia, Turkeylamproites

Abstract: High-MgO lamproite and lamproite-like (i.e., lamprophyric) ultrapotassic rocks are recurrent in the Mediterranean and surrounding regions. They are associated in space and time with ultrapotassic shoshonites and high-K calc-alkaline rocks. This magmatism is linked with the geodynamic evolution of the westernmost sector of the Alpine-Himalaya collisional margin, which followed the closure of the Tethys ocean. Subduction-related lamproites, lamprophyres, shoshonites and high-K calc-alkaline suites were emplaced in the Mediterranean region in the form of shallow level intrusions (e.g., plugs, dykes, and laccoliths), and small volume lava flows, with very subordinate pyroclastic rocks, starting from the Oligocene, in the Western Alps (Northern Italy), through the Late Miocene in Corsica (Southern France) and in Murcia-Almeria (South-Eastern Spain), to the Plio-Pleistocene in Southern Tuscany and Northern Latium (Central Italy), in the Balkan peninsula (Serbia and Macedonia), and in the Western Anatolia (Turkey). The ultrapotassic rocks are mostly lamprophyric, but olivine latitic lavas with a clear lamproitic affinity are also found, as well as dacitic to trachytic differentiated products. Lamproite-like rocks range from slightly silica under-saturated to silica over-saturated composition, have relatively low Al2O3, CaO, and Na2O contents, resulting in plagioclase-free parageneses, and consist of abundant K-feldspar, phlogopite, diopsidic clinopyroxene and highly forsteritic olivine. Leucite is generally absent and it is rarely found only in the groudmasses of Spanish lamproites. Mediterranean lamproites and associated rocks share an extreme enrichment in many incompatible trace elements and depletion in High Field Strength Elements and high, and positively correlated Th/La and Sm/La ratios. They have radiogenic Sr and unradiogenic Nd isotope compositions, high 207Pb over 206Pb and high time integrated 232Th/238U. Their composition requires an originally depleted lithospheric mantle source metasomatised by at least two different agents: i) a high Th/La and Sm/La (i.e., SALATHO) component deriving from lawsonite-bearing, ancient crustal domains likely hosted in mélanges formed during the diachronous collision of the northward drifting continental slivers from Gondwana; ii) a K-rich component derived from a recent subduction and recycling of siliciclastic sediments. These metasomatic melts produced a lithospheric mantle source characterised by network of felsic and phlogopite-rich veins, respectively. Geothermal readjustment during post-collisional events induced progressive melting of the different types of veins and the surrounding peridotite generating the entire compositional spectrum of the observed magmas. In this complex scenario, orogenic Mediterranean lamproites represent rocks that characterise areas that were affected by multiple Wilson cycles, as observed in the the Alpine-Himalayan realm.
DS202107-1093
2021
Mattei, M.Casalini, M., Avanzinellli, R., Tommasini, S., Natali, C., Bianchini, G., Prelevic, D., Mattei, M., Conticelli, S.Petrogenesis of Mediterranean lamproites and associated rocks: the role of overprinted metasomatic events in the postcollisional lithospheric upper mantle.Geological Society London Special Publication, doi.org/10.1144/SP513-2021-36. pdfMantlelamproite

Abstract: High-MgO lamproite and lamproite-like (i.e., lamprophyric) ultrapotassic rocks are recurrent in the Mediterranean and surrounding regions. They are associated in space and time with ultrapotassic shoshonites and high-K calc-alkaline rocks. This magmatism is linked with the geodynamic evolution of the westernmost sector of the Alpine-Himalaya collisional margin, which followed the closure of the Tethys ocean. Subduction-related lamproites, lamprophyres, shoshonites and high-K calc-alkaline suites were emplaced in the Mediterranean region in the form of shallow level intrusions (e.g., plugs, dykes, and laccoliths), and small volume lava flows, with very subordinate pyroclastic rocks, starting from the Oligocene, in the Western Alps (Northern Italy), through the Late Miocene in Corsica (Southern France) and in Murcia-Almeria (South-Eastern Spain), to the Plio-Pleistocene in Southern Tuscany and Northern Latium (Central Italy), in the Balkan peninsula (Serbia and Macedonia), and in the Western Anatolia (Turkey). The ultrapotassic rocks are mostly lamprophyric, but olivine latitic lavas with a clear lamproitic affinity are also found, as well as dacitic to trachytic differentiated products. Lamproite-like rocks range from slightly silica under-saturated to silica over-saturated composition, have relatively low Al2O3, CaO, and Na2O contents, resulting in plagioclase-free parageneses, and consist of abundant K-feldspar, phlogopite, diopsidic clinopyroxene and highly forsteritic olivine. Leucite is generally absent and it is rarely found only in the groudmasses of Spanish lamproites. Mediterranean lamproites and associated rocks share an extreme enrichment in many incompatible trace elements and depletion in High Field Strength Elements and high, and positively correlated Th/La and Sm/La ratios. They have radiogenic Sr and unradiogenic Nd isotope compositions, high 207Pb over 206Pb and high time integrated 232Th/238U. Their composition requires an originally depleted lithospheric mantle source metasomatised by at least two different agents: i) a high Th/La and Sm/La (i.e., SALATHO) component deriving from lawsonite-bearing, ancient crustal domains likely hosted in mélanges formed during the diachronous collision of the northward drifting continental slivers from Gondwana; ii) a K-rich component derived from a recent subduction and recycling of siliciclastic sediments. These metasomatic melts produced a lithospheric mantle source characterised by network of felsic and phlogopite-rich veins, respectively. Geothermal readjustment during post-collisional events induced progressive melting of the different types of veins and the surrounding peridotite generating the entire compositional spectrum of the observed magmas. In this complex scenario, orogenic Mediterranean lamproites represent rocks that characterise areas that were affected by multiple Wilson cycles, as observed in the the Alpine-Himalayan realm.
DS2002-1012
2002
Matteini, M.Matteini, M., Mazzuoli, R., Omarini, R., Cas, R., MaasThe geochemical variations of the upper Cenozoic volcanism along Calama Olacapato El Toro transversalTectonophysics, Vol.345,1-4,Feb.15, pp. 211-27.AndesGeodynamics - tectonics, fault system, Petrogenetic
DS201112-0419
2010
Matteini, M.Hauser, N., Matteini, M., Omarini, R.H., Pimentel, M.M.Constraints on metasomatized mantle under central South America: evidence from Jurassic alkaline lamprophyre dykes from the eastern Cordillera, NM Argentina.Mineralogy and Petrology, Vol. 100, pp. 153-184.South America, ArgentinaLamprophyre
DS201807-1516
2018
Matter, J.M.Mervine, E.M., Wilson, S.A., Power, I.M., Dipple, G.M., Turvey, C.C., Hamilton, J.L., Vanderzee, S., Raudsepp, M., Southam, C., Matter, J.M., Kelemen, P.B., Stiefenhofer, J., Miya, Z., Southam, G.Potential for offsetting diamond mine carbon emissions through mineral carbonation of processed kimberlite: an assessment of De Beers mine sites in South Africa and Canada.Mineralogy and Petrology, 10.1007/ s00710-018- 0589-4, 14p.Africa, South Africa, Canada, Northwest Territories, Ontariodeposit - Venetia, Voorspoed, Gahcho Kue, Victor, Snap Lake

Abstract: De Beers kimberlite mine operations in South Africa (Venetia and Voorspoed) and Canada (Gahcho Kué, Victor, and Snap Lake) have the potential to sequester carbon dioxide (CO2) through weathering of kimberlite mine tailings, which can store carbon in secondary carbonate minerals (mineral carbonation). Carbonation of ca. 4.7 to 24.0 wt% (average?=?13.8 wt%) of annual processed kimberlite production could offset 100% of each mine site’s carbon dioxide equivalent (CO2e) emissions. Minerals of particular interest for reactivity with atmospheric or waste CO2 from energy production include serpentine minerals, olivine (forsterite), brucite, and smectite. The most abundant minerals, such as serpentine polymorphs, provide the bulk of the carbonation potential. However, the detection of minor amounts of highly reactive brucite in tailings from Victor, as well as the likely presence of brucite at Venetia, Gahcho Kué, and Snap Lake, is also important for the mineral carbonation potential of the mine sites.
DS200512-0693
2005
Mattern, E.Mattern, E., Matas, J., Ricard, Y.,Bass, J.Lower mantle composition and temperature from mineral physics and thermodynamic modelling.Geophysical Journal International, Vol. 160, 3, pp. 973-990.MantleGeothermometry
DS200512-0694
2005
Mattern, E.Mattern, E., Matas, J., Ricard, Y., Bass, J.Lower mantle composition and temperature from mineral physics and thermodynamic modelling.Geophysical Journal International, Vol. 160, 3, pp. 973-990.MantleGeothermometry
DS200612-1158
2005
Mattern, E.Ricard, Y., Mattern, E., Matas, J.Synthetic tomographic images of slabs from mineral physics.American Geophysical Union, Geophysical Monograph, ed. Van der Hilst, Earth's Deep mantle, structure ...., No. 160, pp. 283-200.MantleTomography, subduction
DS200712-0694
2007
Mattern, E.Matas, J., Bass, J., Ricard, Y., Mattern, E., Bukowinski, M.S.T.On the bulk composition of the lower mantle: predictions and limitations from generalized inversion seismic profiles.Geophysical Journal International, Vol. 170, 2, August pp. 764-780.MantleGeophysics - seismics
DS1992-1223
1992
MatteyPorcelli, D.R., O'Nions, R.K., Galer, S.J.G., Cohen, A.S., MatteyIsotopic relationships of volatile and lithophile trace elements in continental ultramafic xenolithsContributions to Mineralogy and Petrology, Vol. 110, No. 2-3, pp. 528-538Australia, Arizona, East AfricaUltramafic xenoliths, Geochronology
DS1995-2154
1995
MatteyZinngrebe, E., Foley, S.F., Vannucci, R., Bottazi, MatteyMetasomatism of peridotite by alkaline melt and cognate fluid:microchemical and ion probe evidence from low pressureProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 700-702.Russia, Yakutia, Aldan ShieldMetasomatism, Deposit -Inagli complex
DS2001-1301
2001
MatteyZhang, H.F., Menzies, M.A., Mattey, Hinton, GurneyPetrology, mineralogy and geochemistry of oxide minerals in polymict xenoliths from Bultfontein...Contributions to Mineralogy and Petrology, Vol. 141, No. 3, June, pp. 367-79.South AfricaGeochronology - low bulk rock oxygen ratios, Deposit - Bultfontein
DS2002-1591
2002
MatteyThompson, R.N., Smith, P.M., Gibson, Mattey, DickinAnkerite carbonatite from Swartbooisdrif Namibia: the first evidence for magmatic ferrocarbonatite.Contribution to Mineralogy and Petrology, Vol.143,3,June,pp. 377-96., Vol.143,3,June,pp. 377-96.NamibiaCarbonatite
DS2002-1592
2002
MatteyThompson, R.N., Smith, P.M., Gibson, Mattey, DickinAnkerite carbonatite from Swartbooisdrif Namibia: the first evidence for magmatic ferrocarbonatite.Contribution to Mineralogy and Petrology, Vol.143,3,June,pp. 377-96., Vol.143,3,June,pp. 377-96.NamibiaCarbonatite
DS1986-0536
1986
Mattey, D.Mattey, D., Pillinger, C.T., Menzies, M.A.Abundances and carbon isotope compositions of trapped fluids in mantlediopsides: implications for mantle recycyling modelsProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 276-278GlobalBlank
DS1994-0820
1994
Mattey, D.Jacob, D., Jagoutz, E., Lowry, D., Mattey, D., KudrjavtsevaDiamondiferous eclogites from Siberia: remnants of Archean oceanic crustGeochimica et Cosmochimica Acta, Vol. 58, 23, pp. 5191-207.Russia, SiberiaEclogites, Deposit -Udachnaya
DS1994-1124
1994
Mattey, D.Mattey, D., Lowry, D., Macpherson, C.Oxygen isotope composition of mantle peridotiteEarth Planetary Science Letters, Vol. 128, No. 3-4, Dec. pp. 231-242.MantleGeochronology
DS1996-0899
1996
Mattey, D.Mason, P.R.D., Downes, H., Mattey, D.Crustal assimilation as a major petrogenetic process in the East Carpathian Neogene and Quat. margin arcJournal of Petrology, Vol. 37, No. 4, Aug. 1, pp. 927-960RomaniaTectonics
DS1997-0064
1997
Mattey, D.Baker, J., Matthews, A., Mattey, D., Rowley, D., Xue, F.Fluid-rock interactions during high pressure metamorphism, Dabie Shan, China.Geochimica et Cosmochimica Acta, Vol. 61, No. 8, April pp. 1685-1696.ChinaEclogites, metamorphism
DS1997-0184
1997
Mattey, D.Chazot, G., Lowry, D., Menzies, M., Mattey, D.Oxygen isotopic composition of hydrous and anhydrous mantle peridotitesGeochimica et Cosmochimica Acta, Vol. 61, No. 1, Jan. pp. 161-169.MantlePeridotites, Geochronology
DS1998-0187
1998
Mattey, D.Burgess, R., Johnson, L.H., Mattey, D., Harris, TurnerHelium, Argon, and Carbon isotopes in coated and polycrystalline diamonds.Chemical Geology, Vol. 146, No. 3-4, May 5, pp. 205-218.AustraliaGeochronology, Diamond morphology
DS2003-1544
2003
Mattey, D.Zhang, H.F., Menzies, M.A., Mattey, D.Mixed mantle provenance diverse garnet compositions in polymict peridotitesEarth and Planetary Science Letters, Vol. 216, 3, pp. 329-46.South AfricaGeochemistry
DS200412-2202
2003
Mattey, D.Zhang, H.F., Menzies, M.A., Mattey, D.Mixed mantle provenance diverse garnet compositions in polymict peridotites, Kaapvaal Craton, South Africa.Earth and Planetary Science Letters, Vol. 216, 3, pp. 329-46.Africa, South AfricaGeochemistry
DS1985-0509
1985
Mattey, D.P.Ozima, M., Zashu, S., Mattey, D.P., Pillinger, C.T.Helium, argon and carbon isotopic compositions in diamonds and theirapplications in mantle evolution.*JAPGeochem. Journal, *JAP, Vol. 19, No. 3, pp. 127-134GlobalDiamond Morphology
DS1985-0510
1985
Mattey, D.P.Ozima, M., Zashu, S., Mattey, D.P., Pillinger, C.T.Helium, Argon and Carbon Isotopic Compositions in Diamonds And Their Implications in Mantle Evolution.Geochemical Journal, Vol. 19, No. 3, PP. 127-134.GlobalGeochronology, Diamond Morphology
DS1986-0537
1986
Mattey, D.P.Mattey, D.P.Carbon isotopes in the mantleTerra Cognita, Vol.7, No.4, Autumn, pp. 31-36GlobalMantle genesis, Carbon
DS1987-0076
1987
Mattey, D.P.Boyd, S.R., Mattey, D.P., Pillinger, C.T., Milledge, H.J.Multiple growth events during diamond genesis: an integrated study of carbon and nitrogen isotopes and nitrogen aggregation state in coated stonesEarth and Planetary Science Letters, Vol. 86, pp. 341-353Democratic Republic of CongoMbuji Mayi
DS1987-0197
1987
Mattey, D.P.Exley, R.A., Boyd, S.R., Mattey, D.P., Pillindesly, C.T.Nitrogen isotope geochemistry of basaltic glasses- implications for mantle degasing and structureEarth and Planetary Sci. Letters, Vol. 81, No. 2-3, January pp. 163-174GlobalMantle genesis
DS1987-0447
1987
Mattey, D.P.Mattey, D.P., Exley, R.A., Boyd, S.R., Pillinger, C.T., MenziesCarbon isotopes in oceanic and continental lithosphereTerra Cognita, Conference abstracts Oceanic and Continental Lithosphere:, Vol. 7, No. 4, Autumn, abstract only p. 618GlobalBlank
DS1987-0620
1987
Mattey, D.P.Rogers, N.W., Hawkesworth, C.J., Mattey, D.P., Harmon, R.S.Sediment subduction and the source of potassium in orogenic leucititesGeology, Vol. 15, No. 5, May pp. 451-453GlobalLeucite, Ultrapotassic rocks
DS1988-0293
1988
Mattey, D.P.Hawkesworth, C.J., Kempton, P.D., Mattey, D.P., Palacz, Z.A., Rogers, N.W.Intra-mantle fractionation VS lithosphere recycling:evidence from the sub-continental mantleD. Reidel Publishing Co., Nato Series, Asi C, Math. Phys. Sci., Vol., pp. 227-237Southern AfricaIsotopes- kimberlites, lamproites, Mid Ocean Ridge Basalt (MORB).
DS1989-0959
1989
Mattey, D.P.Mattey, D.P., Exley, R.A., Pillinger, C.T., Menzies, M.A., PorcelliRelationships between Carbon, Heleum, Strontium and neodymium isotopes in mantle diopsidesGeological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 913-921GlobalMantle xenoliths
DS1991-1078
1991
Mattey, D.P.Mattey, D.P., Taylor, W.R., Green, D.H.Carbon isotope fractionation between CO2 vapour and silicate melts at 5-30KBARSTerra, Abstracts of Experimental mineralogy, petrology and, Vol. 2, December abstracts p. 88GlobalExperimental petrology, Carbonatite
DS1992-0980
1992
Mattey, D.P.Macpherson, C., Mattey, D.P., Harris, J.Oxygen isotope analysis of microgram quantities of silicate by a laser fluorination technique dat a for syngenetic inclusions in diamondV.m. Goldschmidt Conference Program And Abstracts, Held May 8-10th. Reston, p. A 66. abstractGlobalDiamond inclusions, Geochemistry
DS1992-1012
1992
Mattey, D.P.Mattey, D.P., Harris, J.Oxygen isotope analysis of syngenetic silicate inclusions in diamond by laser microprobeEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.336South Africa, RussiaWesselton, Mir, Diamond inclusions
DS1994-0289
1994
Mattey, D.P.Chazot, G., Menzies, M.A., Lowry, D., Mattey, D.P.Fluid peridotite interaction in spinel facies mantle: oxygen composition of hydrous and anhydrous lherzolitesInternational Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 70-72.GlobalMetasomatism
DS1994-1060
1994
Mattey, D.P.Lowry, D., Mattey, D.P., Macpherson, C.G., Harris, J.W.Evidence for stable isotope and chemical disequilibrium associated with diamond formation in the mantle.Mineralogical Magazine, Vol. 58A, pp. 535-536. AbstractMantleGeochronology, Diamond genesis
DS1994-1125
1994
Mattey, D.P.Mattey, D.P., et al.Oxygen isotope composition of mantle minerals by laser fluorinationanalysis: homogeneity in peridotites, eclogites.Mineralogical Magazine, Vol. 58A, pp. 573-574. AbstractMantleGeochronology, Peridotites, eclogites
DS1994-1279
1994
Mattey, D.P.Nisbet, E.G., Mattey, D.P., Lowry, D.Can diamonds be dead bacteria?Nature, Vol. 367, No. 6465, February 24, p. 694.GlobalAliphatic hydrocarbons, Diamond mineralogy
DS1995-0240
1995
Mattey, D.P.Burgess, S.R., Turner, G., Mattey, D.P.Helium, argon and carbon isotope constraints on the formation of cubic and polycrystalline diamonds.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 92-94.GlobalGeochronology -noble gas, cubic diamonds, Deposit -Jwaneng, Orapa
DS1998-0676
1998
Mattey, D.P.Jacob, D.E., Mattey, D.P.Geochemistry of layered kyanite bearing eclogites froim the Roberts Victormine.7th International Kimberlite Conference Abstract, pp. 364-5.South AfricaGeochemistry - garnets, Deposit - Roberts Victor
DS1999-0424
1999
Mattey, D.P.Lowry, D., Mattey, D.P., Harris, J.W.Oxygen isotope composition of syngenetic inclusions in diamond from The finsch mine, RSA.Geochimica et Cosmochimica Acta, Vol. 63, No. 11, 12, June 1, pp. 1825-36.South AfricaGeochronology, Deposit - Finsch
DS200612-1421
2006
Mattey, D.P.Thirwall, M.F., Gee, M.A., Lowry, D., Mattey, D.P., Murton, B.J., Taylor, R.N.Low 180 in the Icelandic mantle and its origins: evidence from Reykjanes Ridge and Icelandic lavas.Geochimica et Cosmochimica Acta, Vol. 70, 4, pp. 993-1019.Europe, IcelandGeochronology
DS201705-0877
2017
Mattey, D.P.Sommer, H., Jacob, D.E., Stern, R.A., Petts, D., Mattey, D.P., Pearson, D.G.Fluid induced transition from banded kyanite to bimineralic eclogite and implications for the evolution of cratons.Geochimica et Cosmochimica Acta, in press available 55p.Africa, South AfricaDeposit - Roberts Victor

Abstract: Heterogeneous, modally banded kyanite-bearing and bimineralic eclogites from the lithospheric mantle, collected at the Roberts Victor Diamond mine (South Africa), show a reaction texture in which kyanite is consumed. Geothermobarometric calculations using measured mineral compositions in Perple_X allowed the construction of a P-T path showing a steep, cool prograde metamorphic gradient of 2 °C/km to reach peak conditions of 5.8 GPa and 890 °C for the kyanite eclogite. The kyanite-out reaction formed bimineralic eclogite and is probably an integral part of the mineralogical evolution of most archetypal bimineralic eclogites at Roberts Victor and potentially elsewhere. The kyanite-out reaction occured at close to peak pressure (5.3 GPa) and was associated with a rise in temperature to 1380 °C. Mass balance calculations show that upon breakdown, the kyanite component is fully accommodated in garnet and omphacite via a reaction system with low water fugacity that required restricted fluid influx from metasomatic sources. The ?18O values of garnets are consistently higher than normal mantle values. Each sample has its characteristic trend of ?18O variance between garnets in the kyanite-bearing sections and those in the bimineralic parts covering a range between 5.1‰ and 6.8‰. No systematic change in O-isotope signature exists across the sample population. Differences in garnet trace element signatures between differing lithologies in the eclogites are significant. Grossular-rich garnets coexisting with kyanite have strong positive Eu-anomalies and low Gd/Yb ratios, while more pyrope-rich garnets in the bimineralic sections have lost their positive Eu-anomaly, have higher Gd/Yb ratios and generally higher heavy rare earth element contents. Garnets in the original kyanite-bearing portions thus reflect the provenance of the rocks as metamorphosed gabbros/troctolites. The kyanite-out reaction was most likely triggered by a heating event in the subcratonic lithosphere. As kyanite contains around 100 ppm of H2O it is suggested that the kyanite-out reaction, once initiated by heating and restricted metasomatic influx, was promoted by the release of water contained in the kyanite. The steep (high-P low-T) prograde P-T path defining rapid compression at low heating rates is atypical for subduction transport of eclogites into the lithospheric mantle. Such a trajectory is best explained in a model where strong lateral compression forces eclogites downward to higher pressures, supporting models of cratonic lithosphere formation by lateral collision and compression.
DS201709-2056
2017
Mattey, D.P.Sommer, H., Jacob, D.E., Stern, R.A., Petts, D., Mattey, D.P., Pearson, D.G.Fluid induced transition from banded kyanite to bimineralic eclogite and implications for the evolution of cratons.Goldschmidt Conference, abstract 1p.Africa, South Africadeposit - Roberts Victor

Abstract: Heterogeneous, modally banded kyanite-bearing and bimineralic eclogites from the lithospheric mantle, collected at the Roberts Victor Diamond mine (South Africa), show a reaction texture in which kyanite is consumed. Geothermobarometric calculations using measured mineral compositions in Perple_X allowed the construction of a P-T path showing a steep, cool prograde metamorphic gradient of 2 °C/km to reach peak conditions of 5.8 GPa and 890 °C for the kyanite eclogite. The kyanite-out reaction formed bimineralic eclogite and is probably an integral part of the mineralogical evolution of most archetypal bimineralic eclogites at Roberts Victor and potentially elsewhere. The kyanite-out reaction occured at close to peak pressure (5.3 GPa) and was associated with a rise in temperature to 1380 °C. Mass balance calculations show that upon breakdown, the kyanite component is fully accommodated in garnet and omphacite via a reaction system with low water fugacity that required restricted fluid influx from metasomatic sources. The ?18O values of garnets are consistently higher than normal mantle values. Each sample has its characteristic trend of ?18O variance between garnets in the kyanite-bearing sections and those in the bimineralic parts covering a range between 5.1‰ and 6.8‰. No systematic change in O-isotope signature exists across the sample population. Differences in garnet trace element signatures between differing lithologies in the eclogites are significant. Grossular-rich garnets coexisting with kyanite have strong positive Eu-anomalies and low Gd/Yb ratios, while more pyrope-rich garnets in the bimineralic sections have lost their positive Eu-anomaly, have higher Gd/Yb ratios and generally higher heavy rare earth element contents. Garnets in the original kyanite-bearing portions thus reflect the provenance of the rocks as metamorphosed gabbros/troctolites. The kyanite-out reaction was most likely triggered by a heating event in the subcratonic lithosphere. As kyanite contains around 100 ppm of H2O it is suggested that the kyanite-out reaction, once initiated by heating and restricted metasomatic influx, was promoted by the release of water contained in the kyanite. The steep (high-P low-T) prograde P-T path defining rapid compression at low heating rates is atypical for subduction transport of eclogites into the lithospheric mantle. Such a trajectory is best explained in a model where strong lateral compression forces eclogites downward to higher pressures, supporting models of cratonic lithosphere formation by lateral collision and compression.
DS1994-0288
1994
Matteym D.Chazot, G., Menzies, M.A., Harte, B., Matteym D.Carbonatite metasomatism and melting of the Arabian lithosphere: evidence from trace element composition.Mineralogical Magazine, Vol. 58A, pp. 167-168. AbstractGlobalCarbonatite, Lherzolites
DS1996-0904
1996
Matthai, S.K.Matthai, S.K., Fischer, G.Quantitative modeling of fault fluid discharge and fault dilation induced fluid pressure variations..Geology, Vol. 24, No. 2, Feb. pp. 183-186GlobalSeismogenic zone, Earthquakes
DS1990-0841
1990
Matthes, S.Klemd, R., Matthes, S., Okrusch, M.high pressure relics in metapelitic wallrocks of the Weissenstein eclogite(Munchberg gneiss complex, Germany)Terra, Abstracts of Crustal Dynamics: Pathways and Records held Bochum FRG, Vol. 2, December p. 2GermanyEclogite, metamorphism
DS1991-1253
1991
Matthes, S.Okrusch, M., Matthes, S., Klemd, R., O'Brien, P.J., Schmidt, K.Eclogites at the north-western margin of the Bohemian Massif: a reviewEuropean Journal of Mineralogy, Vol. 3, No. 4, pp. 707-730EuropeEclogites, Mineral chemistry
DS2000-0782
2000
MatthewsPrior, D.J., Wheeler, J., Brenker, F. Harte, MatthewsCrystal plasticity of natural garnet: new microstructural evidenceGeology, Vol. 28, No. 1, Nov. pp. 1003-6.MantleGarnets, xenoliths, kelphite, Microscopy
DS1994-1126
1994
Matthews, A.Matthews, A.Oxygen isotope geothermometers for metamorphic rocksJournal of Metamorphic Geology, Vol. 12, No. 3, May pp. 211-220GlobalGeothermometry, metamorphism
DS1997-0064
1997
Matthews, A.Baker, J., Matthews, A., Mattey, D., Rowley, D., Xue, F.Fluid-rock interactions during high pressure metamorphism, Dabie Shan, China.Geochimica et Cosmochimica Acta, Vol. 61, No. 8, April pp. 1685-1696.ChinaEclogites, metamorphism
DS2003-0025
2003
Matthews, A.Appora, I., Eiler, J.M., Matthews, A., Stolper, E.M.Experimental determination of oxygen isotope fractionation between CO2 vapor andGeochimica et Cosmochimica Acta, Vol. 67, 3, pp. 459-71.GlobalMelilite, Melting
DS2003-0107
2003
Matthews, A.Beyth, M., Avigad, D., Wetzel, H.U., Matthews, A., Berhe, S.M.Crustal exhumation and indications for Snowball Earth in the East African Orogen:Precambrian Research, Vol. 123, 2-4, pp. 187-201.EthiopiaBlank
DS200412-0148
2003
Matthews, A.Beyth, M., Avigad, D., Wetzel, H.U., Matthews, A., Berhe, S.M.Crustal exhumation and indications for Snowball Earth in the East African Orogen: north Ethiopia and east Eritrea.Precambrian Research, Vol. 123, 2-4, pp. 187-201.Africa, EthiopiaTectonics, orogeny
DS1993-1791
1993
Matthews, D.Yates, D., Matthews, D., Deakin, S.Hard rock diamond mining at Argyle Diamond Mines Pty. LtdAustralia Min. Met. Mawby Memorial Volume, Mon. 19, pp. 1443-1448.AustraliaMining, Deposit -Argyle
DS1993-1792
1993
Matthews, D.Yates, D., Matthews, D., Deakin, S.Open pit mining at Argyle diamond mine, western AustraliaThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) , Annual Meeting Abstracts LESS than approximately 10, Vol. 86, No. 968, March ABSTRACT p. 75.AustraliaMining, Mineral processing, Deposit -Argyle
DS1994-1127
1994
Matthews, H.L.Matthews, H.L.Aboriginal community and mineral industry perspectives: mineral business opportunities -issues recommendationsCanadian Institute 1994 Canadian Mining Symposium, Preprint, 40pCanadaEconomics, Aboriginals, legal, law
DS201907-1579
2019
Matthews, K.J.Tetley, M.G., Li, Z-X., Matthews, K.J., Williams, S.E., Muller, R.D.Decoding Earth's plate tectonic history using sparse geochemical data.Geoscience Frontiers, available 12p. PdfMantleplate tectonics

Abstract: Accurately mapping plate boundary types and locations through time is essential for understanding the evolution of the plate-mantle system and the exchange of material between the solid Earth and surface environments. However, the complexity of the Earth system and the cryptic nature of the geological record make it difficult to discriminate tectonic environments through deep time. Here we present a new method for identifying tectonic paleo-environments on Earth through a data mining approach using global geochemical data. We first fingerprint a variety of present-day tectonic environments utilising up to 136 geochemical data attributes in any available combination. A total of 38301 geochemical analyses from basalts aged from 5-0 Ma together with a well-established plate reconstruction model are used to construct a suite of discriminatory models for the first order tectonic environments of subduction and mid-ocean ridge as distinct from intraplate hotspot oceanic environments, identifying 41, 35, and 39 key discriminatory geochemical attributes, respectively. After training and validation, our model is applied to a global geochemical database of 1547 basalt samples of unknown tectonic origin aged between 1000-410 Ma, a relatively ill-constrained period of Earth's evolution following the breakup of the Rodinia supercontinent, producing 56 unique global tectonic environment predictions throughout the Neoproterozoic and Early Paleozoic. Predictions are used to discriminate between three alternative published Rodinia configuration models, identifying the model demonstrating the closest spatio-temporal consistency with the basalt record, and emphasizing the importance of integrating geochemical data into plate reconstructions. Our approach offers an extensible framework for constructing full-plate, deep-time reconstructions capable of assimilating a broad range of geochemical and geological observations, enabling next generation Earth system models.
DS202004-0539
2020
Matthews, K.J.Tetley, M.G., Li, Z-X., Matthews, K.J., Williams, S.E.Decoding Earth's plate tectonic history using sparse geochemical data. RodiniaGeoscience Frontiers, in press available 12p. PdfMantleplate tectonics

Abstract: Accurately mapping plate boundary types and locations through time is essential for understanding the evolution of the plate-mantle system and the exchange of material between the solid Earth and surface environments. However, the complexity of the Earth system and the cryptic nature of the geological record make it difficult to discriminate tectonic environments through deep time. Here we present a new method for identifying tectonic paleo-environments on Earth through a data mining approach using global geochemical data. We first fingerprint a variety of present-day tectonic environments utilising up to 136 geochemical data attributes in any available combination. A total of 38301 geochemical analyses from basalts aged from 5-0 Ma together with a well-established plate reconstruction model are used to construct a suite of discriminatory models for the first order tectonic environments of subduction and mid-ocean ridge as distinct from intraplate hotspot oceanic environments, identifying 41, 35, and 39 key discriminatory geochemical attributes, respectively. After training and validation, our model is applied to a global geochemical database of 1547 basalt samples of unknown tectonic origin aged between 1000-410 Ma, a relatively ill-constrained period of Earth's evolution following the breakup of the Rodinia supercontinent, producing 56 unique global tectonic environment predictions throughout the Neoproterozoic and Early Paleozoic. Predictions are used to discriminate between three alternative published Rodinia configuration models, identifying the model demonstrating the closest spatio-temporal consistency with the basalt record, and emphasizing the importance of integrating geochemical data into plate reconstructions. Our approach offers an extensible framework for constructing full-plate, deep-time reconstructions capable of assimilating a broad range of geochemical and geological observations, enabling next generation Earth system models.
DS200712-0066
2005
Matthews, L.Bellefleur, G., Matthews, L., Roberts,B., McMonnies, B., Salisbury, M., Snyder, D., Perron, G., McGaughty, J.Downhole seismic imaging of the Victor kimberlite, James Bay Lowlands, Ontario: a feasibility study.Geological Survey of Canada Current Research, 2005- C1, 7p.Canada, OntarioGeophysics - seismics
DS1992-1013
1992
Matthews, M.Matthews, M., Harte, B., Prior, D.Mantle garnets - a cracking yarnGeochimica et Cosmochimica Acta, Vol. 56, No. 7, July pp. 2633-2642Lesotho, Southern AfricaMantle geochemistry, Garnets
DS1991-0678
1991
Matthews, M.B.Harte, B., Matthews, M.B., Winterburn, P.A., Gurney, J.J.Aspects of melt composition, crystallization, metasomatism anddistribution, shown by mantle xenoliths from the Matsoku kimberlite pipeProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 167-169South AfricaMantle, Metasomatism
DS1994-1047
1994
Matthews, P.A.Long, R.E., Matthews, P.A., Graham, D.P.The nature of crustal boundaries: combined interpret.of wide angle and normal incidence seismic dataTectonophysics, Vol. 232, pp. 309-318GlobalGeophysics -seismics, Crustal boundaries
DS1994-1048
1994
Matthews, P.A.Long, R.E., Matthews, P.A., Graham, D.P.The nature of crustal boundaries: combined interpret. of wide angle and normal incidence seismic data.Tectonophysics, Vol. 232, pp. 309-318.GlobalGeophysics -seismics, Crustal boundaries
DS1995-0444
1995
Matthews, R.Drever, G., Matthews, R.Metallic and industrial mineral assessment report on the Alberta diamond project in the Hinton area.Alberta Geological Survey, MIN 1995005AlbertaExploration - assessment, Cameco Corp., Dia Met Minerals
DS201809-2072
2018
Matthews, S.Matthews, S., Shorttle, O., Maclennan, J., Rudge, J.F., Miller, W.G.R.Can we detect carbon rich mantle reservoirs?Goldschmidt Conference, 1p. AbstractMantlecarbon

Abstract: The Earth’s surface inventory of carbon is critical for maintaining the planet’s habitability, yet the majority of Earth’s carbon is likely sequestered in the solid Earth. Understanding how Earth’s shallow carbon cycle evolved requires an assesment of the total carbon accreted, how it was distributed between Earth’s reservoirs, and how these reservoirs continue to exchange carbon. The low carbon content of Earth’s depleted upper mantle has been well constrained by primitive olivine hosted melt inclusions and the CO2/3He ratios of magmatic fluids. Using mass balance constraints we show that either the lower mantle is considerably more carbon rich, or the Earth has lost much of its initial carbon inventory. Distinguising between these scenarios is crucial for understanding the development and maintenance of Earth’s shallow carbon cycle. We assess the carbon content of the lower mantle using new melt inclusion datasets from Iceland, sampling both primordial and recycled mantle material. By comparing carbon concentrations with lithophile element concentrations we find evidence that carbon rich material is transported in the Iceland plume. Furthermore, we demonstrate that such datasets provide only a low bound on the true carbon content of the lower mantle, due to fundamental limits imposed by magma mixing, degassing and inclusion decrepitation. Using a global compilation of melt inclusion analyses we argue these processes occur ubiquitously and are likely to limit our ability to robustly resolve high mantle carbon using melt inclusion datasets. By combining these observations with global mass balance constraints we derive new estimates of the carbon content of primordial and recycled mantle material.
DS202104-0615
2021
Matthews, S.Williams, H.M., Matthews, S., Rizo, H., Shorttle, O.Iron isotopes trace primordial magma ocean cummulates melting in Earth's upper mantle.Science Advances, 7, (11) eabc7394 10.1126 /sciad-v.abc7394Europe, Greenlandmagmatism

Abstract: The differentiation of Earth ~4.5 billion years (Ga) ago is believed to have culminated in magma ocean crystallization, crystal-liquid separation, and the formation of mineralogically distinct mantle reservoirs. However, the magma ocean model remains difficult to validate because of the scarcity of geochemical tracers of lower mantle mineralogy. The Fe isotope compositions (?57Fe) of ancient mafic rocks can be used to reconstruct the mineralogy of their mantle source regions. We present Fe isotope data for 3.7-Ga metabasalts from the Isua Supracrustal Belt (Greenland). The ?57Fe signatures of these samples extend to values elevated relative to modern equivalents and define strong correlations with fluid-immobile trace elements and tungsten isotope anomalies (?182W). Phase equilibria models demonstrate that these features can be explained by melting of a magma ocean cumulate component in the upper mantle. Similar processes may operate today, as evidenced by the ?57Fe and ?182W heterogeneity of modern oceanic basalts.
DS2001-0440
2001
Matthews, W.Hamilton, M.A., Goutier, J., Matthews, W.uranium-lead (U-Pb) baddeleyite age for the Paleoproterozoic Lac Esprit dyke swarm, James Bay region, Quebec.Geological Survey of Canada (GSC) Current Research, No. 2001-F5, 17p.Quebec, James Bay LowlandsGeochronology, Yasinski Lake, dike swarm
DS200712-0120
2007
Matthews, W.A.Buchan, K.L., Goutier, J., Hamilton, M.A., Ernst, R.E., Matthews, W.A.Paleomagnetism, U Pb geochronology and geochemistry of Lac Esprit and other dyke swarms, James Bay area, Quebec: implications for Paleoproterozoic deformationCanadian Journal of Earth Sciences, Vol. 44, 5, pp. 643-664.Canada, QuebecDyke swarms
DS1982-0329
1982
Mattick, R.E.King, E.R., Mattick, R.E.Principal Facts for Six Gravity Profiles Across the Midcontinent Gravity High in Iowa and Nebraska.United States Geological Survey (USGS) OPEN FILE., No. 82-1072, 18P.GlobalMid-continent
DS1996-0905
1996
Mattie, P.D.Mattie, P.D., Condie, K.C.Mafic xenoliths from the Navajo volcanic field, Four Corners: constraints on the composition of crust.Geological Society of America, Abstracts, Vol. 28, No. 7, p. A-213.Colorado PlateauXenoliths
DS1997-0743
1997
Mattie, P.D.Mattie, P.D., Condie, K.C., Selverstone, J., Kyle, P.R.Origin of the continental crust in the Colorado Plateau: geochemical evidence from mafic xenoliths....Geochimica et Cosmochimica Acta, Vol. 61, No. 10, May pp. 2007-22.Colorado PlateauXenoliths, Navajo Volcanic Field
DS1993-1389
1993
Mattielli, N.Schiano, P., Clochiatti, R., Mattielli, N., Shimizu, N.Melt and fluid inclusions in peridoite xenoliths from the KerguelenArchipelago.Eos, Transactions, American Geophysical Union, Vol. 74, No. 16, April 20, supplement abstract p. 320.GlobalXenoliths
DS1996-0906
1996
Mattielli, N.Mattielli, N., Weis, D., Giret, A.Kerguelen basic and ultrabasic xenoliths: evidence for hotspot activityLithos, Vol. 37, No. 2/3, April pp. 261-GlobalGeodynamics, Hotspots
DS201212-0558
2012
Mattielli, N.Pivin, M., Debaille, V., Mattielli, N.,Demaiffe, D.Nd-Hf isotope systematics of megacrysts from the Mbuji-Mayi kimberlites, D.R. Congo: implications for the cratonic lithospheric mantle.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractAfrica, Democratic Republic of CongoDeposit - Mbuji-Mayi
DS201312-0202
2013
Mattielli, N.DeBaille, V., O'Neill, C., Brandon, A.D., Haenecour, P., Yin, Q-Z., Mattielli, N., Trieman, A.H.Stagnant lid tectonics in early Earth revealed bu 142 Nd variations in late Archean rocks.Earth and Planetary Science Letters, Vol. 373, pp. 83-92.MantleConvection
DS201312-0711
2013
Mattielli, N.Pivin, M., Debaille, V., Mattielli, N.Nd-Hf isotope systematics of megacrysts from the Mbuji-Mayi kimberlites, D.R. Congo: evidence for a metasomatic origin related to kimberlite interaction with the cratonic lithosphere mantle.Proceedings of the 10th. International Kimberlite Conference, Vol. 1, Special Issue of the Journal of the Geological Society of India,, Vol. 1, pp. 123-136.Africa, Democratic Republic of CongoDeposit - Mbuji-Mayi
DS201610-1859
2016
Mattielli, N.Doucet, L.S., Mattielli, N., Ionov, D.A., Debouage, W., Golovin A.V.Zn isotopic heterogeneity in the mantle: a melting control?Earth and Planetary Science Letters, Vol. 451, pp. 232-240.MantlePeridotite

Abstract: We present new Zn elemental and isotope data on seventeen fertile and refractory mantle peridotite xenoliths. Eleven fertile peridotites are garnet and spinel lherzolites from Vitim and Tariat (Siberia and Mongolia) and represent some of the most pristine fertile peridotites available. Six refractory peridotites are spinel harzburgites from the Udachnaya kimberlite (Siberian craton) that are nearly pristine residues of high-degree polybaric melting at high pressure (7-4 GPa). Geochemical data suggest that Zn isotopic compositions in the peridotites have not been affected by post-melting processes such as metasomatism, contamination by the host-magmas or alteration. The fertile peridotites have uniform Zn concentrations (59±2 ppm59±2 ppm) and Zn isotopic compositions with ?66Zn (relative to JMC-Lyon-03-0749l)?=?+0.30?±?0.03‰ consistent with the Bulk Silicate Earth estimates of ?66Zn?=?+0.28?±?0.05‰ (Chen et al., 2013). The refractory peridotites have Zn concentrations ranging from 30 to 48 ppm and ?66Zn from +0.10±0.01‰+0.10±0.01‰ to +0.18±0.01‰+0.18±0.01‰ with an average of +0.14±0.03‰+0.14±0.03‰. Our data suggest that the lithospheric mantle has a heterogeneous Zn isotopic composition. Modeling of Zn isotope partitioning during partial melting of fertile mantle suggests that high degrees of melt extraction (>30%) may significantly fractionate Zn isotopes (up to 0.16‰) and that during mantle melting, Zn concentrations and isotopic compositions are mainly controlled by the stability of clinopyroxene and garnet within the melting residue. Because the stability of clinopyroxene and garnet is mainly pressure dependent we suggest that both the depth and the degrees of melt extraction may control Zn isotope fractionation during mantle melting.
DS202007-1136
2020
Mattielli, N.Doucet, L.S., Xu, Y., Klaessens, D., Hui, H., Ionov, D.A., Mattielli, N.Decoupled water and iron enrichments in the cratonic mantle: a study on peridotite xenoliths from Tok, SE Siberian craton.American Mineralogist, Vol. 105, pp. 803-819.Russia, Siberia peridotites

Abstract: Water and iron are believed to be key constituents controlling the strength and density of the lithosphere and, therefore, play a crucial role in the long-term stability of cratons. On the other hand, metasomatism can modify the water and iron abundances in the mantle and possibly triggers thermo-mechanical erosion of cratonic keels. Whether local or large scale processes control water distribution in cratonic mantle remains unclear, calling for further investigation. Spinel peridotite xenoliths in alkali basalts of the Cenozoic Tok volcanic field sampled the lithospheric mantle beneath the southeastern margin of the Siberian Craton. The absence of garnet-bearing peridotite among the xenoliths, together with voluminous eruptions of basaltic magma, suggests that the craton margin, in contrast to the central part, lost its deep keel. The Tok peridotites experienced extensive and complex metasomatic reworking by evolved, Ca-Fe-rich liquids that transformed refractory harzburgite to lherzolite and wehrlite. We used polarized Fourier transform infrared spectroscopy (FTIR) to obtain water content in olivine, orthopyroxene (Opx), and clinopyroxene (Cpx) of 14 Tok xenoliths. Olivine, with a water content of 0-3 ppm H2O, was severely degassed, probably during emplacement and cooling of the host lava flow. Orthopyroxene (49-106 ppm H2O) and clinopyroxene (97-300 ppm H2O) are in equilibrium. The cores of the pyroxene grains, unlike olivine, experienced no water loss due to dehydration or addition attributable to interaction with the host magma. The water contents of Opx and Cpx are similar to those from the Kaapvaal, Tanzania, and North China cratons, but the Tok Opx has less water than previously studied Opx from the central Siberian craton (Udachnaya, 28-301 ppm; average 138 ppm). Melting models suggest that the water contents of Tok peridotites are higher than in melting residues, and argue for a post-melting (metasomatic) origin. Moreover, the water contents in Opx and Cpx of Tok peridotites are decoupled from iron enrichments or other indicators of melt metasomatism (e.g., CaO and P2O5). Such decoupling is not seen in the Udachnaya and Kaapvaal peridotites but is similar to observations on Tanzanian peridotites. Our data suggest that iron enrichments in the southeastern Siberian craton mantle preceded water enrichment. Pervasive and large-scale, iron enrichment in the lithospheric mantle may strongly increase its density and initiate a thermo-magmatic erosion. By contrast, the distribution of water in xenoliths is relatively “recent” and was controlled by local metasomatic processes that operate shortly before the volcanic eruption. Hence, water abundances in minerals of Tok mantle xenoliths appear to represent a snapshot of water in the vicinity of the xenolith source regions.
DS202008-1384
2020
Mattielli, N.Doucet, L.S., Li, Z-X., Gamel El Dien, H., Pourteau, A., Murphy, B., Collins, W.J., Mattielli, N., Olierook, H.K.H., Spencer, C.J., Mitchell, R.N.Distinct formation history for deep mantle domains reflected in geochemical differences.Nature Geoscience, Vol. 13, pp. 511-515. pdfMantlegeochemistry

Abstract: The Earth’s mantle is currently divided into the African and Pacific domains, separated by the circum-Pacific subduction girdle, and each domain features a large low shear-wave velocity province (LLSVP) in the lower mantle. However, it remains controversial as to whether the LLSVPs have been stationary through time or dynamic, changing in response to changes in global subduction geometry. Here we compile radiogenic isotope data on plume-induced basalts from ocean islands and oceanic plateaus above the two LLSVPs that show distinct lead, neodymium and strontium isotopic compositions for the two mantle domains. The African domain shows enrichment by subducted continental material during the assembly and breakup of the supercontinent Pangaea, whereas no such feature is found in the Pacific domain. This deep-mantle geochemical dichotomy reflects the different evolutionary histories of the two domains during the Rodinia and Pangaea supercontinent cycles and thus supports a dynamic relationship between plate tectonics and deep-mantle structures.
DS202009-1625
2020
Mattielli, N.Doucet, L.S., Li, Z-X., GamelEl Dien, H., Pourteau, A., Murphy, J.B., Collins, W.J., Mattielli, N., Olierook, H.K.H., Spencer, C.J., Mitchell, R.N.Distinct formation history for deep mantle domains reflected in geochemical differences.Nature Geoscience, Vol. 13, July pp. 511-515. pdfMantlegeochemistry

Abstract: The Earth’s mantle is currently divided into the African and Pacific domains, separated by the circum-Pacific subduction girdle, and each domain features a large low shear-wave velocity province (LLSVP) in the lower mantle. However, it remains controversial as to whether the LLSVPs have been stationary through time or dynamic, changing in response to changes in global subduction geometry. Here we compile radiogenic isotope data on plume-induced basalts from ocean islands and oceanic plateaus above the two LLSVPs that show distinct lead, neodymium and strontium isotopic compositions for the two mantle domains. The African domain shows enrichment by subducted continental material during the assembly and breakup of the supercontinent Pangaea, whereas no such feature is found in the Pacific domain. This deep-mantle geochemical dichotomy reflects the different evolutionary histories of the two domains during the Rodinia and Pangaea supercontinent cycles and thus supports a dynamic relationship between plate tectonics and deep-mantle structures.
DS1995-1180
1995
Mattikalli, N.M.Mattikalli, N.M., Devereux, B.J., Richards, K.S.Integration of remotely sensing satellite images with a Geographical Information systemComputers and Geosciences, Vol. 21, No. 8, October pp. 947-956GlobalRemote sensing, GIS
DS200712-0698
2007
Mattinson, C.G.Mattinson, C.G., Wooden, J.L., Liou, J.G., Bird, D.K., Wu, C.L.Age and duration of eclogite facies metamorphism, North Quaidam HP/UHP terrane, western China.American Journal of Science, Vol. 306, 9, pp. 683-711.ChinaUHP
DS201012-0890
2010
Mattinson, C.G.Zhang, J.X., Mattinson, C.G., Yu, S.Y., Li, J.P., Meng, F.C.U-Pb zircon geochronology of coesite bearing eclogites from the southern Dulan areas of the North Qaidam UHP terrane, northwestern China: spatially and temporallyJournal of Metamorphic Geology, Vol. 28, 9, pp. 955-978.ChinaUHP - subduction
DS201212-0390
2012
Mattinson, C.G.Kylander-Clark, A.R.C., Hacker, B.R., Mattinson, C.G.Size and exhumation rate of ultrahigh pressure terranes linked to orogenic stage.Earth and Planetary Science Letters, Vol. 321-322, pp. 115-120.MantleUHP
DS2003-0527
2003
Mattinson, J.M.Hacker, B.R., Anderson, T.B., Root, D.B., Mehl, L., Mattinson, J.M., WoodenExhumation of high pressure rocks beneath the Solund Basin, Western gneiss regionJournal of Metamorphic Geology, Vol. 21, 6, pp. 613-30.NorwayUHP
DS200412-0758
2003
Mattinson, J.M.Hacker, B.R., Anderson, T.B., Root, D.B., Mehl, L., Mattinson, J.M., Wooden, J.L.Exhumation of high pressure rocks beneath the Solund Basin, Western gneiss region, Norway.Journal of Metamorphic Geology, Vol. 21, 6, pp. 613-30.Europe, NorwayUHP
DS201312-0586
2013
Mattinson, J.M.Mattinson, J.M.Revolution and evolution: 100 years of U-Pb geochronologyElements, Vol. 9, pp. 53-57.TechnologyGeochronology - radioactivity
DS1985-0423
1985
Mattioli, G.S.Mattioli, G.S., Wood, B.J.Upper Mantle Oxygen Fugacity Recorded by Spinel LherzolitesNature, Vol. 322, August 14, pp. 626-628GlobalExperimental Petrology, Lherzolites
DS1987-0448
1987
Mattioli, G.S.Mattioli, G.S., Wood, B.J., Carmichael, I.S.E.Ternary spinel volumes in the system MgAl2O4 Fe3O4 Fe8/3O4:Implications for the effect of P on intrinsic Fo2 measurements of mantle xenolith spinelsAmerican Mineralogist, Vol. 72, pp. 468-480GlobalExperimental Petrology, Mantle xenoliths
DS201912-2830
2019
Mattioli, M.Toscani, L., Salvioli-Mariani, E., Mattioli, M., Tellini, C., Boschetti, T., Iacumin, P., Selmo, E.The pyroclastic breccia of the Cabezo Negro de Tallant ( SE Spain): the first finding of carbonatite volcanism in the internal domain of the Betic Cordillera.Lithos, in press available, 16p.Europe, Spaincarbonatite
DS200512-0695
2004
Mattison, C.G.Mattison, C.G., Zhang, Ru.Y., Tsujimori, T., Liou, J.G.Epidote rich talc kyanite phengite eclogites, Sulu terrane, eastern China: P T fo2 estimates and the significance of epidote talc assemblage in eclogite.American Mineralogist, Vol. 89, pp. 1772-1783.ChinaUHP
DS200512-1243
2005
Mattison, C.G.Zhang, J.X., Yang, J.S., Mattison, C.G., Xu, Z.Q., Meng, F.C., Shi, R.D.Two contrasting eclogite cooling histories, north Qaidam HP/UHP terrane, western China: petrological and isotopic constraints.Lithos, Vol. 84, 1-2, Sept. pp. 51-76.ChinaEclogite, UHP, geochronology
DS1987-0508
1987
Mattison, G.D.Nelson, D.O., Nelson, K.L., Reeves, K.D., Mattison, G.D.Geochemistry of Tertiary alkaline rocks of the Eastern Trans Pecosmagmatic province, TexasContributions to Mineralogy and Petrology, Vol. 97, No. 1, pp. 72-92GlobalAlkaline rocks
DS1998-0967
1998
Mattitelli, N.Mattitelli, N., Weis, D., et al.Evolution of the lithospheric mantle beneath the Kerguelen Archipelago:formation of heterogeneities...Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 973-4.RussiaKerguelen xenoliths, Plume environment
DS1989-0960
1989
Mattoli, G.S.Mattoli, G.S., Baker, M.B., Rutter, M.J., Stolper, E.M.Upper mantle oxygen fugacity and its relationship to MetasomatismJournal of Geology, Vol. 97, No. 5, September pp. 521-536HawaiiUpper mantle, Xenoliths
DS201412-0561
2014
Matton, G.Matton, G., Jebrak, M.The "eye of Africa" Richat dome, Mauritania: an isolated Cretaceous alkaline-hydrothermal complex.Journal of African Earth Sciences, Vol. 97, pp. 109-124.Africa, MauritaniaAlkalic
DS201512-1979
2015
Matton, G.Tremblay, J., Bedard, L.P., Matton, G.A petrographic study of Nb-bearing minerals at the Saint-Honore niobium deposit.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 75-82.Canada, QuebecNiobium

Abstract: The mineralogy of rare earth element (REE) ore deposits is critical in understanding their petrogenesis but also has signifi cant implications for metallurgy. Like many ore deposits, high-grade rocks do not necessarily equate to positive economic viability and this is especially true for REE deposits. Consequently, knowledge of sample mineralogy acquired early in a project’s life can lead to more effi cient exploration programs through confi rmation of either ‘good’ or ‘bad’ mineralogy. Many REE minerals show fi ne grain sizes and their accumulation can be diffi cult to recognize in hand sample or drill core with an unaided eye. Knowledge of their distribution before sampling can ensure that the best rocks or core lengths are sampled for petrographic or detailed study. REE minerals generally have complex yet diagnostic absorption patterns in visible to shortwave infrared (VNIRSWIR) refl ectance spectra that are driven primarily by REErelated 4f-4f intraconfi gurational electronic transitions. Our recent research (Turner et al., 2014, Turner 2015) has focused on three important mineral classes: REE fl uorocarbonates (bastnaesite, synchysite, and parisite), REE phosphates (monazite, xenotime, and britholite), and REE-bearing silicates (cerite, mosandrite, kainosite, zircon and eudialyte). Refl ectance spectra were acquired in the visible to short wave infrared regions (500 nm to 2500 nm) and samples were characterized using scanning electron microscopy and electron microprobe analysis. The results of our work and publications from other research groups (e.g., Rowan et al., 1986, Swayze et al., 2013, Hoefen et al., 2014, Boesche et al., 2015) have shown the strong applicability of refl ectance spectroscopy and hyperspectral imaging to understanding, exploring, and exploiting rare earth element ore deposits and their associated rocks.
DS201906-1274
2019
Matton, G.Bedard, L.P., Desjardins, D., Matton, G.The importance of syenite enclaves in the evolution of the Saint-Honore alkaline complex.GAC/MAC annual Meeting, 1p. Abstract p. 60.Canada, QuebecCarbonatite

Abstract: The Saint-Honoré alkaline complex located near the Saguenay River (Grenville Province, Québec) has a syenite outer rim and concentric units of calcio-, magnesio- to ferro-carbonatite moving towards the centre. The Mg-carbonatite hosts a niobium deposit, and the Fe-carbonatite hosts a rare earth-rich zone at its centre. The Nb mineralization has a close spatial relationship to the syenite enclaves suggesting that the syenites may have played a critical role in concentrating the pyrochlore (Pcl). There are two forms of Nb mineralization: high- and low-grade. Low-grade mineralization is characterized by highly variable Pcl chemistry with higher U concentrations and a low abundance of fluoroapatite (Ap), whereas high-grade mineralization has a consistent Pcl chemistry (low-U), abundant Ap (with many acicular crystals) and more abundant phlogopite and magnetite. Some of the Pcl crystals have been altered to columbite by hydrothermal processes. It is interpreted that the metamict Pcl (rich in radioactive elements) was altered more readily than the Pcl having undamaged crystal structure. The high-grade mineralization is generally located near the syenite enclaves. Syenite enclaves (from a centimetre scale to several tens of metres in size) reacted with the carbonatite magma to produce a phlogopite rim. Ap is also abundant along the immediate contact between the enclaves and Mg-carbonatite. Large enclaves show hydro-fracturing by the carbonatite suggesting they were crystalline enough to be brittle. There are smaller textures (3-6 mm in diameter) that share many similarities with the syenite enclaves; however, these textures are rounded and could be interpreted as being related to liquid immiscibility. The interaction of carbonatite magma with syenite enclaves is interpreted to have started with abundant crystallization of acicular Ap which depleted the magma in F and lowered the magma's Nb-solubility. Pcl then crystallized in abundance in the vicinity of the syenite enclaves to create the economic Nb-rich zone.
DS1960-0576
1965
Matton, R.B.Matton, R.B.Upheaval Dome, San Juan County, UtahAmerican Association of Petroleum Geologists Bulletin., Vol. 49, No. 3, P. 349. (abstract.).United States, Utah, Colorado Plateau, Rocky MountainsDiatreme
DS200912-0482
2009
Mattson, H.B.Mattson, H.B., Reusser, E.Incomplete mixing of silicate carbonatite magmas during the explosive eruption of Oldoinyo Lengai. September 2007.Goldschmidt Conference 2009, p. A849 Abstract.Africa, TanzaniaCarbonatite
DS201606-1128
2016
Mattson, H.R.Weidendorfer, D., Schmidt, M.W., Mattson, H.R.Fractional crystallization of Si-undersaturated alkaline magmas leading to unmixing of carbonatites on Brava Island ( Cape Verde) and a general model of carbonatite genesis in alkaline magma suites.Contributions to Mineralogy and Petrology, Vol. 171, pp. 43-50.Europe, Cape Verde IslandsCarbonatite

Abstract: The carbonatites of Brava Island, Cape Verde hot spot, allow to investigate whether they represent small mantle melt fractions or form through extreme fractionation and/or liquid immiscibility from CO2-bearing silicate magmas. The intrusive carbonatites on Brava Island are part of a strongly silica-undersaturated pyroxenite, ijolite, nephelinite, nepheline syenite, combeite-foiditite, carbonatite series. The major and trace element composition of this suite is reproduced by a model fractionating olivine, clinopyroxene, perovskite, biotite, apatite, titanite, sodalite and FeTi oxides, all present as phenocrysts in the rocks corresponding to their fractionation interval. Fractionation of ~90 wt% crystals reproduces the observed geochemical trend from the least evolved ultramafic dikes (bulk X Mg = 0.64) to syenitic compositions. The modelled fractional crystallization leads to alkali enrichment, driving the melt into the carbonatite-silicate miscibility gap. An initial CO2 content of 4000 ppm is sufficient to saturate in CO2 at the point where the rock record suggests continuing unmixing carbonatites from nephelinites to nepheline syenites after 61 wt% fractionation. Such immiscibility is also manifested in carbonatite and silicate domains on a hand-specimen scale. Furthermore, almost identical primary clinopyroxene, biotite and carbonate compositions from carbonatites and nephelinites to nepheline syenites substantiate their conjugate character and our unmixing model. The modelled carbonatite compositions correspond to the natural ones except for their much higher alkali contents. The alkali-poor character of the carbonatites on Brava and elsewhere is likely a consequence of the release of alkali-rich CO2 + H2O fluids during final crystallization, which cause fenitization in adjacent rocks. We propose a general model for carbonatite generation during alkaline magmatism, where the fractionation of heavily Si-undersaturated, alkaline parent melts results in alkali and CO2 enrichment in the evolving melt, ultimately leading to immiscibility between carbonatites and evolved Si-undersaturated alkaline melts. Early saturation in feldspathoids or feldspars would limit alkali enrichment preventing the formation of carbonatites. The complete and continuous fractionation line from almost primitive melts to syenitic compositions on Brava underlines the possibly important role of intrusives for hot spot volcanism.
DS1993-1429
1993
Mattson, P.H.Seyler, M., Mattson, P.H.Gabbroic and pyroxenite layers in the Tinaquillo peridotite: succession of melt intrusions in a rising mantle diapir.Journal of Geology, Vol. 101, pp. 501-11.VenezuelaPlumes, Peridotite - alpine type
DS2001-0295
2001
Mattsson, H.Elming, S.A., Mattsson, H.Post Jotnian basic intrusions in the Fennoscandian Shield and the break up of Baltica from Laurentia.Precambrian Research, Vol. 108, No. 3, June 1, pp. 215-36.GlobalGeophysics - paleomagnetics, AMS
DS201012-0348
2010
Mattsson, H.B.Keller, J., Klaudius, J., Kervyn, M., Ernst, G.G.J., Mattsson, H.B.Fundamental changes in the activity of the natrocarbonatite volcano Oldoinyo Lengai, Tanzania.Bulletin of Volcanology, Vol. 72, 8, pp. 893-912. also pp. 913-931.Africa, TanzaniaCarbonatite
DS201112-0719
2011
Mattsson, H.B.Nandedkar, R.H., Mattsson, H.B., Ulmer, P.Petrology of the Lake Natron Engaruka monogenetic volcanic fields, Gregory Rift (northern Tanzania).Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterAfrica, TanzaniaAlkalic
DS201212-0447
2012
Mattsson, H.B.Martin, L.H.J., Schmidt, M.W., Mattsson, H.B., Ulmer, P., Hametner, K., Gunther, D.Element partitioning between immiscible carbonatite-kamafugite melts with application to the Italian ultrapotassic suite.Chemical Geology, Vol. 320-321 pp. 96-112.Europe, ItalyCarbonatite
DS201212-0450
2012
Mattsson, H.B.Mattsson, H.B.Rapid magma ascent and short eruption durations in the Lake Natron-Engaruka monogenetic volcanic field ( Tanzania): a case study of the olivine melilitic Pello Hill scoria cone.Journal of Volcanology and Geothermal Research, Vol. 247-248, Dec. 1, pp. 16-25.Africa, TanzaniaDynamics of vent facies kimberlitic eruptions
DS201312-0070
2013
Mattsson, H.B.Berghuijs, J.F., Mattsson, H.B.Magma ascent, fragmentation and depositional characteristics of "dry" maar volcanoes: similarities with vent facies kimberlite deposits.Journal of Geology and Volcanology Research, Vol. 252, pp. 53-72.MantleCrater rim stratigraphy - melilitite
DS201312-0579
2013
Mattsson, H.B.Martin, L.H.J., Schmidt, M.W., Mattsson, H.B., Guenther, D.Element partitioning between immiscible carbonatite and silicate melts for dry and H2O bearing systems at 1-3 Gpa.Journal of Petrology, Vol. 54, pp. 2301-2338.MantleCarbonatite
DS201312-0589
2013
Mattsson, H.B.Mattsson, H.B., Nandedkar, R.H., Ulmer, P.Petrogenesis of the melilititic and nephenilinitic rock suites in the Lake Natron-Engaruka monogenetic volcanic fields, northern Tanzania.Lithos, Vol. 179, pp. 175-192.Africa, TanzaniaMetasomatism
DS201412-0061
2014
Mattsson, H.B.Bosshard-Stadlin, S.A., Mattsson, H.B., Keller, J.Magma mixing and forced exsolution of CO2 during the explosive 2007-8 eruption of Oldoinyo Lengai ( Tanzania).Journal of Volcanology and Geothermal Research, Vol. 285, pp. 229-246.Africa, TanzaniaMagmatism
DS201412-0062
2014
Mattsson, H.B.Bosshard-Stadlin, S.A., Mattsson, H.B., Keller, J.Magma mixing and forced exsolution of CO2 during the explosive 2007-2008 eruption of Oldoinyo Lengai ( Tanzania).Journal of Volcanology and Geothermal Research, Vol. 285, pp. 229-246.Africa, TanzaniaCarbonatite
DS201412-0562
2014
Mattsson, H.B.Mattsson, H.B., Kervyn, M.Insights into a carbonatite volcano, Kerimasi, N. Tanzania.Volcanic and Magmatic Studies Group meeting, Poster Held Jan. 6-8. See minsoc websiteAfrica, TanzaniaCarbonatite
DS201706-1110
2017
Mattsson, H.B.Weidendorfer, D., Schmidt, M.W., Mattsson, H.B.A common origin of carbonatite magmas.Geology, Vol. 45, 6, pp. 507-510.Africa, Tanzaniacarbonatite - Oldoinyo Lengai

Abstract: The more than 500 fossil Ca-carbonatite occurrences on Earth are at odds with the only active East African Rift carbonatite volcano, Oldoinyo Lengai (Tanzania), which produces Na-carbonatite magmas. The volcano's recent major explosive eruptions yielded a mix of nephelinitic and carbonatite melts, supporting the hypothesis that carbonatites and spatially associated peralkaline silicate lavas are related through liquid immiscibility. Nevertheless, previous eruption temperatures of Na-carbonatites were 490-595 °C, which is 250-450 °C lower than for any suitable conjugate silicate liquid. This study demonstrates experimentally that moderately alkaline Ca-carbonatite melts evolve to Na-carbonatites through crystal fractionation. The thermal barrier of the synthetic Na-Ca-carbonate system, held to preclude an evolution from Ca-carbonatites to Na-carbonatites, vanishes in the natural system, where continuous fractionation of calcite + apatite leads to Na-carbonatites, as observed at Oldoinyo Lengai. Furthermore, saturating the Na-carbonatite with minerals present in possible conjugate nephelinites yields a parent carbonatite with total alkali contents of 8-9 wt%, i.e., concentrations that are realistic for immiscible separation from nephelinitic liquids at 1000-1050 °C. Modeling the liquid line of descent along the calcite surface requires a total fractionation of ?48% calcite, ?12% apatite, and ?2 wt% clinopyroxene. SiO2 solubility only increases from 0.2 to 2.9 wt% at 750-1200 °C, leaving little leeway for crystallization of silicates. The experimental results suggest a moderately alkaline parent to the Oldoinyo Lengai carbonatites and therefore a common origin for carbonatites related to alkaline magmatism.
DS201708-1582
2017
Mattsson, H.B.Weidendorfer, D., Schmidt, M.W., Mattsson, H.B.A common origin of carbonatite magmas.Geology, Vol. 45, 6, pp. 507-510.Africa, Tanzaniacarbonatites

Abstract: The more than 500 fossil Ca-carbonatite occurrences on Earth are at odds with the only active East African Rift carbonatite volcano, Oldoinyo Lengai (Tanzania), which produces Na-carbonatite magmas. The volcano’s recent major explosive eruptions yielded a mix of nephelinitic and carbonatite melts, supporting the hypothesis that carbonatites and spatially associated peralkaline silicate lavas are related through liquid immiscibility. Nevertheless, previous eruption temperatures of Na-carbonatites were 490–595 °C, which is 250–450 °C lower than for any suitable conjugate silicate liquid. This study demonstrates experimentally that moderately alkaline Ca-carbonatite melts evolve to Na-carbonatites through crystal fractionation. The thermal barrier of the synthetic Na-Ca-carbonate system, held to preclude an evolution from Ca-carbonatites to Na-carbonatites, vanishes in the natural system, where continuous fractionation of calcite + apatite leads to Na-carbonatites, as observed at Oldoinyo Lengai. Furthermore, saturating the Na-carbonatite with minerals present in possible conjugate nephelinites yields a parent carbonatite with total alkali contents of 8–9 wt%, i.e., concentrations that are realistic for immiscible separation from nephelinitic liquids at 1000–1050 °C. Modeling the liquid line of descent along the calcite surface requires a total fractionation of ?48% calcite, ?12% apatite, and ?2 wt% clinopyroxene. SiO2 solubility only increases from 0.2 to 2.9 wt% at 750–1200 °C, leaving little leeway for crystallization of silicates. The experimental results suggest a moderately alkaline parent to the Oldoinyo Lengai carbonatites and therefore a common origin for carbonatites related to alkaline magmatism.
DS201710-2216
2017
Mattsson, H.B.Bosshard-Stadlin, S.A., Mattsson, H.B., Stewart, C., Reusser, E.Leaching of lava and tephra from the Oldoinyo Lengai volcano ( Tanzania): remobilization of fluorine and other potentially toxic elements in surface waters of the Gregory Rift.Journal of Volcanology and Geothermal Research, Vol. 322, pp. 14-25.Africa, Tanzaniadeposit - Oldoinyo Lengai

Abstract: Volcanic ash leachate studies have been conducted on various volcanoes on Earth, but few have been done on African volcanoes until now. Tephra emissions may affect the environment and the health of people living in this area, and therefore we conducted a first tephra (ash and lapilli sized) leachate study on the Oldoinyo Lengai volcano, situated in northern Tanzania. The recent explosive eruption in 2007-2008 provided us with fresh samples from the first three weeks of the eruption which were used for this study. In addition, we also used a natrocarbonatitic sample from the activity prior to the explosive eruption, as the major activity at Oldoinyo Lengai is natrocarbonatitic. To compare the leaching process affecting the natrocarbonatitic lavas and the tephras from Oldoinyo Lengai, the 2006 natrocarbonatitic lava flow was resampled 5 years after the emplacement and compared to the initial, unaltered composition. Special interest was given to the element fluorine (F), since it is potentially toxic to both humans and animals. A daily intake of fluoride (F?) in drinking water of > 1.5 mg/l can lead to dental fluorosis, and higher concentrations lead to skeletal fluorosis. For this reason, a guideline value for fluoride in drinking water was set by the WHO (2011) to 1.5 mg/l. However, surface waters and groundwaters in the Gregory Rift have elevated fluoride levels of up to 9.12 mg/l, and as a consequence, an interim guideline value for Tanzania has been set at 8 mg/l. The total concentration of fluorine in the samples from the natrocarbonatitic lava flow is high (3.2 wt%), whereas we observed a significant decrease of the fluorine concentration (between 1.7 and 0.5 wt%) in the samples collected three days and three weeks after the onset of the explosive 2007-08 eruption. However, the total amount of water-extractable fluoride is lower in the natrocarbonatitic lavas (319 mg/l) than in the nephelinitic tephra (573-895 mg/l). This is due to the solubility of the different F-bearing minerals. In the natrocarbonatites, fluorine exists predominantly in fluorite (CaF2), and in the early tephra as Na-Mg bearing salts such as neighborite (NaMgF3) and sellaite (MgF2). All these three minerals have very low solubility in water (16-130 mg/l). The later nephelinitic tephras contain surface coating of villiaumite (NaF), which is highly soluble (42,200 mg/l) in water and can thus release the fluoride more readily upon contact with water. Although there is still the need for further data and a more precise study on this topic in Tanzania, we can already draw a first conclusion that the intake of water during or directly following the deposition of the tephra is not advisable and should be avoided, whereas the release of fluoride from the lava flow has less influence on the river waters.-
DS201805-0961
2018
Mattsson, H.B.Mattsson, H.B., Balashova, A., Almqvist, S.A., Bosshard-Stadlin, S.A., Weidendorfer, D.Magnetic mineralogy and rock properties of silicate and carbonatite rocks from Oldoinyo Lengai volcano (Tanzania).Journal of African Earth Sciences, Vol. 142, pp. 193-206.Africa, Tanzaniadeposit - Oldoinyo Lengai

Abstract: Oldoinyo Lengai, a stratovolcano in northern Tanzania, is most famous for being the only currently active carbonatite volcano on Earth. The bulk of the volcanic edifice is dominated by eruptive products produced by silica-undersaturated, peralkaline, silicate magmas (effusive, explosive and/or as cumulates at depth). The recent (2007-2008) explosive eruption produced the first ever recorded pyroclastic flows at this volcano and the accidental lithics incorporated into the pyroclastic flows represent a broad variety of different rock types, comprising both extrusive and intrusive varieties, in addition to various types of cumulates. This mix of different accidental lithics provides a unique insight into the inner workings of the world's only active carbonatite volcano. Here, we focus on the magnetic mineralogy and the rock magnetic properties of a wide selection of samples spanning the spectrum of Oldoinyo Lengai rock types compositionally, as well from a textural point of view. Here we show that the magnetic properties of most extrusive silicate rocks are dominated by magnetite-ulvöspinel solid solutions, and that pyrrhotite plays a larger role in the magnetic properties of the intrusive silicate rocks. The natrocarbonatitic lavas, for which the volcano is best known for, show distinctly different magnetic properties in comparison with the silicate rocks. This discrepancy may be explained by abundant alabandite crystals/blebs in the groundmass of the natrocarbonatitic lavas. A detailed combination of petrological/mineralogical studies with geophysical investigations is an absolute necessity in order to understand, and to better constrain, the overall architecture and inner workings of the subvolcanic plumbing system. The results presented here may also have implications for the quest in order to explain the genesis of the uniquely natrocarbonatitic magmas characteristic of Oldoinyo Lengai.
DS201810-2294
2018
Mattsson, H.B.Balashova, A., Mattsson, H.B., Hirt, A.M.New tephrostratigraphic data from Lake Emakat ( northern Tanzania): implications for the eruptive history of the Oldoinyo Lengai volcano. ( melilitites)Journal of African Earth Sciences, Vol. 147, pp. 374-382.Africa, Tanzaniadeposit - Oldoinyo Lengai

Abstract: The northern Tanzanian sector of the Gregory Rift is an area of an active continental rifting, in which sedimentation processes are strongly affected by volcanism. Due to limited stratigraphic exposure, the volcanic record of the region is rather sparse, and assigning volcanic centres for the individual eruptions is difficult. This study presents new data on the tephrostratigraphy of the sedimentary sequence of Lake Emakat, Empakaai Crater, northern Tanzania. Seven volcanic ash layers are identified and described from a 1.1-m core of lake sediments. Geochemical, mineralogical, petrographic and magnetic analyses show that: (1) all ash layers are products of highly explosive eruptions of melilite-bearing magmas; (2) most of the eruptions originate from a complex magmatic system; (3) all ash horizons are very well preserved in the lake environment; and (4) there are significant fluctuations of the bulk magnetic susceptibility of the lacustrine sediments which is related to microtephra from additional eruptions, the result of detritus, washed from the shore during periods of strong lake level fluctuations or periods of high erosion rates, or simply by the contamination by the material from the ash layers. Based on geochemistry and mineralogy of the seven identified ash layers in Lake Emakat, combined with the eruption ages from ¹?C datings, we can pinpoint Oldoinyo Lengai volcano as the source of these specific layers. The combination of this new data with existing chronological data from Ryner et al. (2007), retrieved from the same core, provides precise ages of the voluminous highly explosive eruptions in this region of East Africa during the Pleistocene-Holocene transition.
DS201903-0552
2019
Mattsson, H.B.Weidendorfer, D., Schmidt, M.W., Mattsson, H.B.Mineral resorption triggers explosive mixed silicate-carbonatite eruptions.Earth and Planetary Science Letters, Vol. 510, pp. 219-230.Africa, Tanzaniadeposit - Oldoinyo Lengai

Abstract: Historic eruptions of Earth's only active carbonatite volcano, Oldoinyo Lengai (Tanzania), have repeatedly switched from low energy carbonatite lava extrusion to highly energetic explosive silicate volcanism, most recently in 1966-67 and 2007-08. The explosive eruptions produce strongly Si-undersaturated peralkaline silicate ashes with unusually high (Na + K)/Al of 3.4-6.3 when compared to the average peralkalinity of ?0.8 in the East African Rift System. A series of experiments in the carbonatite-clinopyroxene system at 750-1150 °C, 0.1 GPa, reveal that augitic clinopyroxene breaks down peritectically at >900 °C yielding strongly peralkaline conjugated silicate- and carbonatite melts. The clinopyroxene-derived silicate melt dissolves (Na,K)2O from the (Na,K)2CO3-component of the carbonatite leading to high peralkalinities and to liberation of excess CO2, since the solubility of carbon dioxide in silicate liquids is ?1 wt.% at subvolcanic pressures. Carbonatite injection into subvolcanic clinopyroxene-rich crystal mushes hence explains the occurrence of strongly peralkaline silicate melts and provides a mechanism for CO2-driven explosive eruptions. The silicate melt compositions mostly depend on the (Na + K)/Ca ratio of the intruding carbonatite, the silicate ashes erupted in 1966-67 and 2007-08 require an interaction of a clinopyroxene-rich crystal mush with a slightly less evolved alkali-carbonatite than presently erupted at Oldoinyo Lengai. The mechanism identified here, where mineral breakdown induced melt hybridization triggers volatile saturation and highly explosive volcanism is generally applicable to igneous systems that involve carbonatites or other low-viscosity CO2-bearing alkaline silicate melts.
DS201907-1561
2019
Mattsson, H.B.Mattsson, H.B., Hogdahl, K., Carlsson, M., Malehmir, A.The role of mafic dykes in the petrogenesis of the Archean Siilinjarvi carbonatite complex, east central Finland.Lithos, in press available, 37p.Europe, Finlandcarbonatites

Abstract: The Archean (~2.6?Ga) Siilinjärvi carbonatite complex in east-central Finland is crosscut by a few ultramafic lamprophyre dykes, together with a broad array of more evolved mafic dykes that range in composition from foidites to various types of alkali basalts. A possible genetic link between the primitive lamprophyres and the carbonatite complex has previously been hypothesised, but their exact relations have been unclear due to the regional metamorphic overprint (i.e., greenschist facies). Here we focus on the petrology and petrography of the mafic dykes, and integrate the data to present a coherent model that can explain the genesis of the Siilinjärvi carbonatite complex. Field-relations, in combination with petrography and geochemistry, indicate that there are at least three generations of mafic dykes present. The oldest dykes (Generation I) are strongly deformed, and inferred to have been emplaced shortly after the formation of the complex itself. These dykes can be divided into two groups (i.e., ultramafic lamprophyres and Group A), where Group A comprises foidites characterised by low SiO2 (41.4-51.5?wt%) and high alkali (>10?wt% K2O) content. We interpret the foiditic magmas to have evolved from primitive ultramafic lamprophyres by fractionating a clinopyroxene-olivine dominated mineral assemblage that was devoid of feldspar. This fractionation path forced alkali-enrichment in the magmas belonging to Group A, which pushed them into the miscibility gap, and resulted in liquid immiscibility that produced moderately alkaline conjugate carbonatite(s). Subsequent fractionation of the conjugate carbonatite by predominantly calcite and apatite produced the mineralogically homogeneous carbonatite cumulate that is exposed at Siilinjärvi. Younger, less deformed, mafic dykes (belonging to Generations II and III) exhibit trace element characteristics, broadly similar to basaltic dyke swarms in the region. The younger dykes are characterised by the presence of large plagioclase crystals in thin sections. Crystallisation of a feldspar-bearing mineral assemblage resulted in only moderate enrichment of alkalis with increased fractionation, which caused the younger dykes to evolve along the more common basalt-to-trachyte series. Thus, the magmas belonging to Generations II and III at Siilinjärvi never fulfilled the conditions required to produce carbonatites by liquid immiscibility.
DS201707-1383
2017
Mattsson B.Wiedendorfer, D., Schmidt, M.W., Mattsson B.A common origin of carbonatite magmas. Oldoinyo LengaiGeology, Vol. 45, 6, pp. 507-510.Africa, Tanzaniacarbonatite

Abstract: The more than 500 fossil Ca-carbonatite occurrences on Earth are at odds with the only active East African Rift carbonatite volcano, Oldoinyo Lengai (Tanzania), which produces Na-carbonatite magmas. The volcano’s recent major explosive eruptions yielded a mix of nephelinitic and carbonatite melts, supporting the hypothesis that carbonatites and spatially associated peralkaline silicate lavas are related through liquid immiscibility. Nevertheless, previous eruption temperatures of Na-carbonatites were 490–595 °C, which is 250–450 °C lower than for any suitable conjugate silicate liquid. This study demonstrates experimentally that moderately alkaline Ca-carbonatite melts evolve to Na-carbonatites through crystal fractionation. The thermal barrier of the synthetic Na-Ca-carbonate system, held to preclude an evolution from Ca-carbonatites to Na-carbonatites, vanishes in the natural system, where continuous fractionation of calcite + apatite leads to Na-carbonatites, as observed at Oldoinyo Lengai. Furthermore, saturating the Na-carbonatite with minerals present in possible conjugate nephelinites yields a parent carbonatite with total alkali contents of 8–9 wt%, i.e., concentrations that are realistic for immiscible separation from nephelinitic liquids at 1000–1050 °C. Modeling the liquid line of descent along the calcite surface requires a total fractionation of ?48% calcite, ?12% apatite, and ?2 wt% clinopyroxene. SiO2 solubility only increases from 0.2 to 2.9 wt% at 750–1200 °C, leaving little leeway for crystallization of silicates. The experimental results suggest a moderately alkaline parent to the Oldoinyo Lengai carbonatites and therefore a common origin for carbonatites related to alkaline magmatism.
DS1986-0539
1986
Mattyash, I.V.Mazykin, V.V., Mattyash, I.V., Kvasnitska, V.N., Argunov, K.P., ZinchukESR spectra of neutron irradiated diamonds.(Russian)Dopl. Akad. Nauk UKR. B.Geol, (Russian), No. 10, pp. 10-12GlobalMineralogy
DS200512-0004
2004
Matukhin, R.G.Afanasiev, V.P., Griffin, W.L., Natapov, L.M., Zinchuk, N.N., Matukhin, R.G., Mikrtychiyan, G.A.Diamond prospects in the southwestern flank of the Tungusk synclise.Geology of Ore Deposits, Vol. 47, 1, pp. 45-62.Russia, YakutiaDaldyn, Tychany, geochemistry
DS200712-0538
2007
Matukov, D.IKhudolev, A.K., Kropachev, A.P., Tkachenko, V.I., Rublev, A.G., Sergeev, S.A., Matukov, D.I,LyahnitskayaMesoproterozoic to Neoproterozoic evolution of the Siberian Craton and adjacent microcontinents: an overview with constraints for a Laurentian Connection.SEPM Special Publication 86, pp. 209-226.RussiaCraton
DS200712-0539
2007
Matukov, D.IKhudolev, A.K., Kropachev, A.P., Tkachenko, V.I., Rublev, A.G., Sergeev, S.A., Matukov, D.I,LyahnitskayaMesoproterozoic to Neoproterozoic evolution of the Siberian Craton and adjacent microcontinents: an overview with constraints for a Laurentian Connection.SEPM Special Publication 86, pp. 209-226.RussiaCraton
DS200712-0568
2007
Matukov, D.I.Kontinen, A., Kapyaho, A., Huhma, H., Karhu, J., Matukov, D.I., Larionov, A., Sergeev, S.A.Nurmes paragneisses in eastern Finland, Karelian Craton: provenance, tectonic setting and implications for Neoarchean craton correlation.Precambrian Research, Vol. 152, 3-4, pp. 119-148.Europe, FinlandKarelian Craton
DS200712-0573
2006
Matukov, D.I.Koreshkova, M.Yu., Nikitina, L.P., Vladykin, N.V., Matukov, D.I.U Pb dating of zircon from the lower crustal xenoliths, Udachnaya pipe, Yakutia.Doklady Earth Sciences, Vol. 411, 9, Nov-Dec. pp. 1389-1392.Russia, YakutiaDeposit - Udachnaya
DS200712-0928
2007
Matukov, D.I.Saltykova, A.K., Nikitina, L.P., Matukov, D.I.U Pb age and REE dat a (SHRIMP II) on zircons in mantle xenoliths from alkaline basalts ( Vitim area, Transbaikalia): implications for upper mantle partial..Plates, Plumes, and Paradigms, 1p. abstract p. A870.MantleMelting
DS1991-1281
1991
Matushi, Y.Ozima, M., Zashu, S., Tomura, K., Matushi, Y.Constraints from mobile gas contents on the origin of carbonado diamondsNature, Vol. 351, No. 6326, June 6, pp. 472-474GlobalDiamond inclusions, Carbonado -gas
DS200712-1117
2007
MatushkinVernikovskaya, I.V., Salnikova, Matushkin, YasnevThe Neoproterozoic alkaline rocks of the Yenisey Ridge, western margin of the Siberian Craton: mineralogy, geochemistry and geochronology.Plates, Plumes, and Paradigms, 1p. abstract p. A1065.RussiaIjolite
DS201312-0751
2012
Matushkin, N.Yu.Romanova, I.V., Vernikovskaya, A.E., Vernikovsky, V.A., Matushkin, N.Yu., Larionov, A.N.Neoproterozoic alkaline magmatism and associated igneous rocks in the western framing of the Siberian craton: petrography, geochemistry, and geochronology.Russian Geology and Geophysics, Vol. 53, 11, pp. 1176-1196.RussiaMagmatism
DS1997-1127
1997
MatveevSuvorov, V.D., Timirshin, Yruin, Parasotka, MatveevRatio of deep seated and near surface structures in the southern part Of the Yakutian kimberlite province.Russian Geology and Geophysics, Vol. 38, No. 5, pp. 1054-61.Russia, YakutiaGeophysics - seismics, Tectonics, structures
DS2001-0192
2001
MatveevChudinovskikh, L.T., Zharikov, Ishbulatov, MatveevMechanisms of high pressureotassium content in corporation into high pressure clinopyroxeneDoklady Academy of Sciences, Vol. 381, No. 8, Oct/Nov. pp. 956-9.GlobalMineralogy
DS1995-1181
1995
Matveev, S.Matveev, S., Ballhaus, C., Frick, K., et al.Synthesis of C H O fluids at high pressureProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 356-358.MantleIgneous processes, Fluid composition
DS1998-1452
1998
Matveev, S.Taylor, W.R., Matveev, S.Recalibration of the 5 parameter MRK equation of state for C O H fluids in upper mantle conditions...tests7th International Kimberlite Conference Abstract, pp. 895-6.MantleChemical composition
DS200412-1248
2004
Matveev, S.Matveev, S., Creighton, S., Stachel, T.The hydrogen content of olivine - a new tool for diamond exploration.Geological Association of Canada Abstract Volume, May 12-14, SS14-04 p. 263.abstractCanada, Northwest Territories, Africa, South AfricaSpectroscopy
DS200512-0696
2005
Matveev, S.Matveev, S., Portnyagin, M., Ballhaus, C., Brooker, R., Geiger, C.A.Spectrum of phenocryst olivine as an indicator of silica saturation in magmas.Journal of Petrology, Vol. 46, 3, pp. 603-614.MantleMagmatism
DS200512-0909
2005
Matveev, S.Rohrbach, A., Schuth, S., Ballhaus, C., Munker, C., Matveev, S., Qopoto, C.Petrological constraints on the origin of arc picrites, New Georgia Solomon Islands.Contributions to Mineralogy and Petrology, Vol. 149, 6, pp. 685-712.Asia, Solomon IslandsPicrite
DS200612-0730
2006
Matveev, S.Kopylova, M.G., Matveev, S., Raudsepp, M.Searching for primary kimberlite magma,Emplacement Workshop held September, 5p. extended abstractCanada, Northwest TerritoriesDeposit, Jericho, Gahcho Kue, melts
DS200612-0881
2006
Matveev, S.Matveev, S., Creighton, S., Stachel, T.OH in peridotitic olivines entrained in kimberlitic magma.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 24. abstract only.MantleMagmatism - olivine mineral chemistry
DS200712-0569
2007
Matveev, S.Kopylova, M.G., Matveev, S., Raudsepp, M.Searching for parental kimberlite melt.Geochimica et Cosmochimica Acta, Vol. 71, 14, July 15, pp. 3616-3629.MantleDiamond genesis
DS200712-0570
2007
Matveev, S.Kopylova, M.G., Matveev, S., Raudsepp, M.Searching for parental kimberlite melt.Geochimica et Cosmochimica Acta, Vol. 71, 14, July 15, pp. 3616-3629.MantleDiamond genesis
DS200712-0571
2007
Matveev, S.Kopylova, M.G., Matveev, S., Raudsepp, M.Complex history and abundance of volatiles in kimberlite melts.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.236-237.MantleKimberlite petrology
DS200712-0572
2007
Matveev, S.Kopylova, M.G., Matveev, S., Raudsepp, M.Complex history and abundance of volatiles in kimberlite melts.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.236-237.MantleKimberlite petrology
DS200712-0699
2006
Matveev, S.Matveev, S., Stachel, T.Unleashing olivine's potential as a first class kimberlite indicator mineral through FTIR spectroscopy.34th Yellowknife Geoscience Forum, p. 90. abstractTechnologyDatabase - olivine, nickel content
DS200712-0700
2007
Matveev, S.Matveev, S., Stachel, T.OH in mantle olivine: experiment vs nature.Plates, Plumes, and Paradigms, 1p. abstract p. A638.MantleOlivine
DS200712-0701
2007
Matveev, S.Matveev, S., Stachel, T.FTIR spectroscopy of OH in olivine: a new tool in kimberlite exploration.Geochimica et Cosmochimica Acta, Vol. 71, pp. 5528-5543,Canada, Northwest Territories, SaskatchewanSpectroscopy
DS200712-0702
2007
Matveev, S.Matveev, S., Stachel, T.FTIR spectroscopy of OH in olivine- a new tool in kimberlite exploration.Geochimica et Cosmochimica Acta, In press, availableTechnologySpectroscopy
DS200812-0249
2009
Matveev, S.Creighton, S., Stachel, S., Matveev, S., Hofer, H., McCammon, C., Luth, R.W.Oxidation of the Kaapvaal lithospheric mantle driven by metasomatism.Contributions to Mineralogy and Petrology, Vol. 157, pp. 491-504.Africa, South AfricaMetasomatism, Kimberley
DS200812-0343
2008
Matveev, S.Fedortchouk, Y., Matveev, S., Charnell, C., Carlson, J.A.Kimberlitic fluid as recorded by dissolving diamonds and crystallizaing olivine phenocrysts in five Lac de Gras kimberlites, Northwest Territories, Canada.9IKC.com, 3p. extended abstractCanada, Northwest TerritoriesDeposit - Ekati
DS200812-0724
2008
Matveev, S.Matveev, S., Stachel, T.Differences in FTIR spectra measured in olivines derived from depleted and metasomatised sections of the Earth's mantle.Goldschmidt Conference 2008, Abstract p.A606.Africa, South Africa, Canada, OntarioDeposit - Finsch, Victor
DS200912-0135
2009
Matveev, S.Creighton, S.,Stachel, T., Matveev, S., Hofer, H., McCammon, C., Luth, R.W.Oxidation of the Kaapvaal lithospheric mantle driven by metasomatism.Contributions to Mineralogy and Petrology, Vol. 157, 4, pp. 491-504.Africa, South AfricaMetasomatism
DS200912-0483
2009
Matveev, S.Matveev, S., Stachel,T.Evaluation of diamond potential using FTIR spectroscopy of xenocrystic olivine.Lithos, In press available, 18p.Africa, Ghana, Canada, Northwest TerritoriesDeposit - Birim, Diavik
DS201012-0195
2010
Matveev, S.Fedortchuk, Y., Matveev, S., Carlson, J.A.H2O and CO2 in kimberlitic fluid as recorded by diamonds and olivines in several Ekati diamond mine kimberlites, Northwest Territories, Canada.Earth and Planetary Science Letters, Vol. 289, 3-4, pp. 549-559.Canada, Northwest TerritoriesDeposit - Ekati
DS201412-0356
2014
Matveev, S.Hilchie, L., Fedortchouk, Y., Matveev, S., Kopylova, M.G.The origin of high hydrogen content in kimberlitic olivine: evidence from hydroxyl zonation in olivine from kimberlites and mantle xenoliths.Lithos, Vol. 202-203, pp. 429-441.Canada, Nunavut, Northwest Territories, Africa, LesothoDeposit - Jericho, Beartooth, Pipe 200, Matsoku
DS201705-0885
2017
Matveev, S.van den Heuvel, Q., Matveev, S., Drury, M., Gress, M., Chinn, I., Davies, G.Genesis of diamond inclusions: an integrated cathodluminescence ( CL) and electron backscatter diffraction (EBSD) study on eclogitic and peridotitic inclusions and their diamond host.European Geosciences Union General Assembly 2017, Vienna April 23-28, 1p. 6564 AbstractAfrica, BotswanaDeposit - Jwaneng, Letlhakane
DS201810-2308
2018
Matveev, S.Davies, G.R., van den Heuvel, Q., Matveev, S., Drury, M.R., Chinn, I.L., Gress, M.U.A combined catholuminescence and electron backscatter diffraction examination of the growth relationships between Jwaneng diamonds and their eclogitic inclusions.Mineralogy and Petrology, doi.org/10.1007/s00710-018-0634-3 12p.Africa, Botswanadeposit - Jwaneng

Abstract: To fully understand the implications of the compositional information recorded by inclusions in diamond it is vital to know if their growth was syn- or protogenetic and the extent to which they have equilibrated with diamond forming agents. The current paradigm is that the majority of inclusions in diamond are syngenetic but recently this assumption has been questioned. This study presents an integrated cathodoluminescence (CL) and electron backscatter diffraction (EBSD) study of 8 diamonds containing eclogitic inclusions: 19 pyrope-almandine garnets, 12 omphacitic clinopyroxenes, 4 sulphides, 1 coesite and 1 rutile from the Jwaneng diamond mine, Botswana. Diamond plates were sequentially polished to expose inclusions at different levels and CL imaging and EBSD were performed to constrain the relationship between diamond and inclusion growth. Despite complex growth and resorption, individual diamonds are single crystals with a homogeneous crystallographic orientation. All individual inclusions have homogeneous crystallographic orientation and no resolvable compositional zonation. The combined CL and EBSD data suggest that epitaxial inclusion-diamond growth is rare (none of 24 inclusions) and that the imposition of cubo-octahedral faces on inclusions does not necessarily result in epitaxy. Individual diamonds contain inclusions that record evidence of both syngentic and protogenetic relationships with the host diamond and in one case an inclusion appears syngenetic to the diamond core but protogenetic to the growth zone that surrounds 70% of the inclusion. These findings emphasise that inclusions in diamonds have multiple modes of origin and that in order to validate the significance of geochronological studies, further work is needed to establish that there is rapid chemical equilibration of protogenetic inclusions with diamond forming agents at mantle temperatures.
DS201810-2312
2009
Matveev, S.Fedortchouk, Y., Matveev, S.Surface features on diamonds and water content of olivine from kimberlite as indicators of fluid systems in kimberlite magma. EkatiAtlantic Geology, Vol. 45, p. 28. 1p. AbstractCanada, Northwest Territoriesmagmatism
DS1994-0858
1994
Matveev, S.V.Kadik, A.A., Matveev, S.V., et al.Gamma activation determination of nitrogen in silicate in the studies Of the earth's mantle degassing.Journal of Analytical Chemistry, Vol. 49, No. 1, Jan. pp. 110-115.MantleBlank
DS2002-1013
2002
Matveev, Y.A.Matveev, Y.A., Litvin, Y.A., Perchuk, L.L.Melting equilibration temperatures of the CaMgSiO3 Mg3Al2Si3O12 K2 Ca (Co2) system modelling a source composition of carbonate - silicate diamond bearing rocks Kokchetav18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.242. (poster)RussiaMineralogy - melting
DS201212-0381
2012
Matveeva, O.P.Kriulina, G.Y., Kyazimov, V.O., Vasillev, E.A., Matveeva, O.P.New dat a on the structure of the cubic habit diamonds from the M.V. Lomonosov diamond deposit. Archangelsk Diamondiferous Province, Russia.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractRussia, Archangel, Kola PeninsulaDeposit - Lomonosov
DS1950-0286
1956
Matveieff, D.Matveieff, D.Compures Geologiques de Sibiti Est et OestAef Dir. Mines Et Geol., SECT. B, No. 7, PP. 43-46.GlobalGeology
DS1993-0981
1993
Matveyenkov, V.V.Matveyenkov, V.V., Almukhamedov, A.I., Dashevskaya, D.M.Amphibole pyroxenite xenoliths from the Gorringe Bank (northeasternAtlantic).Doklady Academy of Sciences USSR, Earth Science Section, Vol. 316, No. 3, pp. 99-101.GlobalXenoliths
DS1960-0010
1960
Matveyeva, G.V.Apenko, M.A., Matveyeva, G.V., Plotnikova, M.I.Documents on the Study of Diamonds and Diamond Fields of The UssrLeningrad: All Union Geol. Institute Press, Nov. Ser., No. 40.RussiaKimberlite
DS1981-0257
1981
Matyash, I.V.Kvasnitsa, V.N., Mazykin, V.V., Matyash, I.V., Tsymbal, S.N.(epa Spectra of Small Natural Diamonds and Their Possible Geneticificance.)Mineral. Zhur., Vol. 3, No. 1, PP. 89-92.RussiaKimberlite
DS1987-0036
1987
Matyash, I.V.Bartoshinskii, Z.V., Matyash, I.V., Mazykin, V.V., Bekesha, S.N.Major nitrogen paramagnetic centers in diamonds from placers of northeastern Siberian PlatformMineral. Zhurn., (Russian), Vol. 9, No. 3, pp. 87-89RussiaBlank
DS1991-0773
1991
Matyash, I.V.Ivanitskiy, V.P., Kharkiv, A.D., Matyash, I.V., Polozov, A.G.NMR spectra of magnetite from kimberlite and iron ore deposits of the Siberian Platform*(in Russian)Mineral. Zhurn., (Russian), Vol. 13, No. 2, April pp. 45-54RussiaUdachnaya pipe, Geochemistry
DS1986-0390
1986
Matyashm I.V.Ivanitskiy, V.P., Matyashm I.V., Kharkiv, A.D.Crystal chemical pecularities of phlogopite of mantle origin according to NMR data.(Russian)Mineral Zhurn., (Russian)-UKR., Vol. 8, No. 3, pp. 41-48RussiaCrystallography
DS1995-0161
1995
Matysek, P.Bobrowksy, P.T., Sibbick, S.J., Newell, J.N., Matysek, P.Drift exploration in the Canadian CordilleraBritish Columbia Ministry of Energy and Mines, Paper 1995-2, 304p. $ 40.00British ColumbiaGeochemistry, Drift exploration- review
DS1995-0162
1995
Matysek, P.F.Bobrowsky, P.T., Sibbick, S.J., Newell, J.M., Matysek, P.F.Drift exploration in the Canadian CordilleraBritish Columbia Energy Mines Resources, Paper, 1995-2, 290p.British Columbia, YukonGeomorphology, Drift prospecting - applicable to gold
DS1989-0961
1989
Matyska, C.Matyska, C.Angular symmetries of hotspot distributionsEarth and Planetary Science Letters, Vol. 95, No. 3/4, November pp. 334-340GlobalGeothermometry, Hotspots, craton
DS1994-1128
1994
Matyska, C.Matyska, C., Moser, J., Yuen, D.A.The potential influence of radiative heat transfer on the formation of megaplumes in the lower mantle.Earth and Planetary Science Letters, Vol. 125, pp. 255-266.MantlePlumes, Heat transfer
DS2000-0634
2000
Matyska, C.Matyska, C., Yuen, D.A.Profiles of the Bulletinen parameter from mantle convection modellingEarth and Planetary Science Letters, Vol. 178, No. 1-2, May 15, pp.39-46.MantleMantle plumes, Convection
DS2001-0741
2001
Matyska, C.Matyska, C., Yuen, D.A.Are mantle plumes adiabatic?Earth and Planetary Science Letters, Vol. 189, No. 3-4, July 15, pp. 165-76.MantlePlumes - thermodynamic, density, heat, pressure
DS2002-1014
2002
Matyska, C.Matyska, C., Yuen, D.A.Bullen's parameter: a link between seismology and geodynamical modellingEarth and Planetary Science Letters, Vol.198,3-4,pp.471-83., Vol.198,3-4,pp.471-83.GlobalGeodynamics
DS2002-1015
2002
Matyska, C.Matyska, C., Yuen, D.A.Bullen's parameter: a link between seismology and geodynamical modellingEarth and Planetary Science Letters, Vol.198,3-4,pp.471-83., Vol.198,3-4,pp.471-83.GlobalGeodynamics
DS200512-0697
2005
Matyska, C.Matyska, C., Yuen, D.A.The importance of radiative heat transfer on superplumes in the lower mantle with the new post perovskite phase change.Earth and Planetary Science Letters, Vol. 234, 1-2, pp. 71-81.MantleGeothermometry
DS200612-0882
2006
Matyska, C.Matyska, C., Yuen, D.A.Lower mantle dynamics with the post perovskite phase change, radiative thermal conductivity, temperature and depth dependent viscosity.Physics of the Earth and Planetary Interiors, Vol. 154, 2, Feb. 16, pp. 196-207.MantleGeothermometry, core mantle boundary
DS200712-0703
2007
Matyska, C.Matyska, C., Yuen, D.A.Lower mantle material properties and convection models of multiscale plumes.Plates, plumes and Planetary Processes, pp. 137-164.MantleConvection
DS200812-1303
2007
Matyska, C.Yuen, D.A., Matyska, C., Cadek, O., Kameyama, M.The dynamical influences from physical properties in the lower mantle and post perovskite phase transition.AGU American Geophysical Union Monograph, No. 174, pp. 249-270.MantleTectonics
DS1990-1605
1990
Matyukhin, V.V.Yakovleva, T.P., Leskina, L.M., Matyukhin, V.V., Yampolskaya, E.G.Functional state and sickness rate of diamond processing workers. (Russian)Gig Tr Prof. Zabol., (russian), No. 8, pp. 38-42RussiaDiamond processing, Workers
DS1996-0907
1996
Matyunin, A.Matyunin, A.Diamond bearing kimberlites of the activized cratons of Khanka massif(Primorye) Russia.International Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 395.RussiaKimberlites
DS1999-0622
1999
Matyunin, A.P.Sakno, V.G., Matyunin, A.P., Zimin, S.S.The mineral composition of Diamondiferous kimberlite type rocks in the northern Khanka Massif, primorsk ..Doklady Academy of Sciences, Vol. 368, No. 7, pp. 920-23.RussiaMineralogy, Deposit - Khanka Massif
DS2001-1003
2001
Matyunin, A.P.Sakhno, V.G., Matyunin, A.P., Moiseenko, V.G.Isotopic signatures of kimberlites in the Kurkhan Diamondiferous diatreme, Primore region.Doklady Academy of Sciences, Vol. 380, No. 7, Sept-Oct. pp.833-6.RussiaGeochronology
DS2002-1386
2002
Matyunin, A.P.Sakhno, V.G., Moiseenko, V.G., Zhuravlev, D.Z., Matyunin, A.P.Sm Nd ages of Diamondiferous kimberlites of the Kurkhan diatreme in the Khanka Massif, Primor'e region.Doklady Earth Sciences, Vol. 387A, 9, pp. 1110-1112.RussiaGeochronology
DS2002-1387
2002
Matyunin, A.P.Sakhno, V.G., Moiseenko, V.G., Zhuravlev, D.Z., Matyunin, A.P.Sm Nd age of Diamondiferous kimberlites of the Kurkhan diatreme in the Khanka Massif Primore region.Geochemistry International, Vol. 40, 12, pp. 110-2.RussiaGeochronology
DS2000-0282
2000
Matzel, J.Farmer, G.L., Letser, A.C., Bowring, S., Matzel, J.Composition of the lower continental crust beneath the Cheyenne Belt S. WyoGeological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-386.Wyoming, ColoradoGeochronology - isotopic evidence, Xenoliths - mafic
DS2000-0635
2000
Matzel, J.Matzel, J., Bowring, S., Stevns, L., Williams, M.I.Geochronology of lower crustal xenoliths from across the State Line Belt, S. Wyoming and N. Colorado.Geological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-387.Wyoming, ColoradoGeochronology, Deposit - Leucite Hills, State Line
DS200712-0304
2005
Matzel, J.Farmer, G.L., Bowring, S.A., Williams, M.I., Christiensen, N.I., Matzel, J., Stevens, I.Contrasting lower crustal evolution across an Archean Proterozoic suture, physical, chemical and geochronologic studies of lower crustal xenoliths....Keller & Karlstrom: The Rocky Mountain Region, American Geophysical Union, No. 154, pp. 139-162.United States, Wyoming, Colorado PlateauGeochronology
DS201511-1851
2015
Matzel, J.Kaminsky, F., Matzel, J., Jacobsen, B., Hutcheon, I., Wirth, R.Isotopic fractionation of oxygen and carbin in decomposed lower-mantle inclusions in diamond. Rio Soriso Mineralogy and Petrology, DOI 10. 1007/s00710-015-0401-7South America, Brazil, Mato GrossoJuina area

Abstract: Two carbonatitic mineral assemblages, calcite + wollastonite and calcite + monticellite, which are encapsulated in two diamond grains from the Rio Soriso basin in the Juina area, Mato Grosso State, Brazil, were studied utilizing the NanoSIMS technique. The assemblages were formed as the result of the decomposition of the lower-mantle assemblage calcite + CaSi-perovskite + volatile during the course of the diamond ascent under pressure conditions from 15 to less than 0.8 GPa. The oxygen and carbon isotopic compositions of the studied minerals are inhomogeneous. They fractionated during the process of the decomposition of primary minerals to very varying values: ?18O from ?3.3 to +15.4?‰SMOW and ?13C from ?2.8 to +9.3?VPDB. These values significantly extend the mantle values for these elements in both isotopically-light and isotopically-heavy areas.
DS200512-0278
2005
Matzel, J.P.Farmer, G.L., Bowring, S.A., Willams, M.L., Christensen, N.I., Matzel, J.P., Stevens, L.Contrasting lower crustal evolution across an Archean Proterozoic suture: physical, chemical and geochronologic studies of lower crustal xenoliths in southern Wyoming and northern Colorado.American Geophysical Union, Geophysical Monograph, No. 154, pp. 139-162.United States,Wyoming, Colorado PlateauGeophysics - seismics, tectonics
DS201412-0989
2013
Matzen, A.K.Wood, B.J., Kiseeva, E.S., Matzen, A.K.Garnet in the Earth's mantle.Elements, Vol. 9, 6, Dec. pp. 421-426.MantlePeridotite, eclogites, diamond inclusions
DS201708-1577
2017
Matzen, A.K.Matzen, A.K., Wood, B.J., Baker, M.B., Stolper, E.M.The roles of pyroxenite and peridotite in the mantle sources onf oceanic basalt.Nature Geoscience, Vol. 10, pp. 530-535/Mantleperidotites

Abstract: Subduction of oceanic crust generates chemical and lithological heterogeneities in the mantle. An outstanding question is the extent to which these heterogeneities contribute to subsequent magmas generated by mantle melting, but the answer differs depending on the geochemical behaviour of the elements under investigation: analyses of incompatible elements (those that preferentially concentrate into silicate melts) suggest that recycled oceanic crust is an important contributor, whereas analyses of compatible elements (those that concentrate in crystalline residues) generally suggest it is not. Recently, however, the concentrations of Mn and Ni—two elements of varying compatibility—in early-crystallizing olivines, have been used to infer that erupted magmas are mixtures of partial melts of olivine-rich mantle rocks (that is, peridotite) and of metasomatic pyroxene-rich mantle rocks (that is, pyroxenite) formed by interaction between partial melts of recycled oceanic crust and peridotite. Here, we test whether melting of peridotite alone can explain the observed trend in olivine compositions by combining new experimental data on the partitioning of Mn between olivine and silicate melt under conditions relevant to basalt petrogenesis with earlier results on Ni partitioning. We show that the observed olivine compositions are consistent with melts of fertile peridotite at various pressures—importantly, melts from metasomatic pyroxenites are not required. Thus, although recycled materials may well be present in the mantle source regions of some basalts, the Mn and Ni data can be explained without such a contribution. Furthermore, the success of modelling the Mn–Ni contents of olivine phenocrysts as low-pressure crystallization products of partial melts of peridotite over a range of pressures implies a simple new approach for constraining depths of mantle melting.
DS1860-0157
1871
Mauch, K.Mauch, K.K. Mauch's Wasserfahrt von Potchefstroom Nach Den Diamant felden Am Vaal Fluss.Petermans Geograf. Mitt., Vol. 17, P. 70; PP. 254-257.Africa, South Africa, Cape ProvinceTravelogue
DS1910-0074
1910
Maucher, W.Maucher, W.Die Neuesten Resultate der Diamant forschung in Deutsch Suedwestafrika.Jber. Freiberg. Geol. Gesell., Vol. 3, P. 9.Southwest Africa, NamibiaDiamond, Current Activities
DS2000-0749
2000
Maud, R.R.Partridge, T.C., Maud, R.R.Macro scale geomorphic evolution of southern AfricaIn: The Cenozoic of Southern Africa, pp. 3-18.South AfricaGeomorphology - alluvials, tectonics, gravels
DS2002-1016
2002
Maude Lake ExplorationMaude Lake ExplorationNew acqusition for Maude Lake... Otish areaMaude Lake Exploration, Feb. 21, 1p.Quebec, Otish MountainsNews item - press release
DS2002-1017
2002
Maude Lake ExplorationMaude Lake ExplorationNew diamond exploration targets for Maude Lake in the Wemindji Otish areaMaude Lake Resources, Jan. 23, 2p.Quebec, Otish MountainsNews item - press release
DS200712-1012
2007
Maudit, T.Sokoutis, D., Corti, G., Bonin, M., Brun, J.P., Cloetingh, S., Maudit, T., Manetti, P.Modelling the extension of heterogeneous hot lithosphere.Tectonophysics, Vol. 444, pp. 63-79.MantleRheology, back arc extension
DS1910-0586
1919
Maufe, H.B.Maufe, H.B.Platinum Metals in the Somabula Diamondiferous GravelsGeological Survey Southern Rhodesia SHORT REPORT., No. 5, 1P.ZimbabwePlatinum, Diamond
DS2003-0862
2003
Mauger, A.Mahoney, S., James, P., Mauger, A., Heinson, G.Geologic and regolith mapping for mineral exploration in the Gawler Craton of SouthInternational Geoscience and Remote Sensing Symposium, Vol. 3, pp. III 1779-81. Ingenta 1034976078AustraliaRemote sensing
DS200412-1202
2003
Mauger, A.Mahoney, S., James, P., Mauger, A., Heinson, G.Geologic and regolith mapping for mineral exploration in the Gawler Craton of South Australia using Hyperion and other remote seInternational Geoscience and Remote Sensing Symposium, Vol. 3, pp. III 1779-81. Ingenta 1034976078AustraliaRemote sensing
DS1984-0497
1984
Mauger, R.L.Mauger, R.L.Origin of ocelli in an early carboniferous minette near Concord, NorthCarolinaGeological Society of America, Vol. 16, No. 3, p. 179. (abstract.)United States, Appalachia, North CarolinaMinette
DS1985-0424
1985
Mauger, R.L.Mauger, R.L.The Petrology and Plate Tectonic Interpretation of Minette Dikes Near Harrisburg, North Carolina.Geological Society of America (GSA), Vol. 17, No. 2, JANUARY P. 122. (abstract.).United States, North Carolina, AppalachiaPetrography, Geochemistry, Mineral Chemistry, Genesis
DS1985-0425
1985
Mauger, R.L.Mauger, R.L.Early Carboniferous Minettes from the Charlotte Belt, South cental North Carolina, UsaGeological Association of Canada (GAC)., Vol. 10, P. A37. (abstract.).United States, North Carolina, AppalachiaBlank
DS1988-0446
1988
Mauger, R.L.Mauger, R.L.Ocelli: transient disequilibrium features in a Lower Carboniferousminette near Concord, North CarolinaCanadian Mineralogist, Vol. 26, No. 1, March pp. 117-132GlobalBlank
DS1988-0447
1988
Mauger, R.L.Mauger, R.L.Geochemical evidence for sediment recycling from North Carolin a (United States (US))minettesCanadian Mineralogist, Vol. 26, No. 1, March pp. 133-142GlobalBlank
DS1991-1411
1991
Mauger, R.L.Reid, J.C., Mauger, R.L., Weiner, L.S., Maybin, A.H.III.Diamond-lamproite model- proposed explanation for North Carolin a and SouthCarolin a diamondsGeological Society of America Abstracts, Vol. 23, No. 1, February p. 121GlobalLamproite, Diamond genesis
DS1989-0962
1989
Mauk, J.J.Mauk, J.J., Seasor, R.O., Kelly, W.C., Van der Plum, B.A.The relationship between structure and second stage copper mineralization in the White Pine district of the Midcontinent Rift, northern MichiganGeological Society of America (GSA) Annual Meeting Abstracts, Vol. 21, No. 6, p. A130. AbstractMichiganMidcontinent, Tectonics
DS201012-0075
2010
Maukonen, D.Brusentsova, T.N., Peale, R.E., Maukonen, D., Harlow, G.E., Boesenberg, J.S., Ebel, D.Far infrared spectroscopy of carbonate minerals.American Mineralogist, Vol. 95, pp. 1515-1522.TechnologyIR - not specific to diamonds
DS2001-0742
2001
Mauler, A.Mauler, A., Godard, G., Kunze, K.Crystallographic fabrics of omphacite, rutile and quartz in Vendee eclogites. Consequences - deformationTectonophysics, Vol. 342, No. 1-2, Dec. pp. 81-112.FranceArmorican Massif, Eclogites
DS200412-1249
2004
Maumus, J.Maumus, J., Laporte, D., Schiano, P.Dihedral angle measurements and infiltration property of SIO2 rich melts in mantle peridotite assemblages.Contributions to Mineralogy and Petrology, Vol. 148, 1, pp. 1-12.MantleMineralogy - peridotites
DS201711-2513
2017
Maunder, B.Freeburn, R., Bouilhol, P., Maunder, B., Magni, V., van Hunen, J.Numerical models of the magmatic processes induced by slab breakoff.Earth and Planetary Science Letters, Vol. 478, pp. 203-213.Mantlesubduction

Abstract: After the onset of continental collision, magmatism often persists for tens of millions of years, albeit with a different composition, in reduced volumes, and with a more episodic nature and more widespread spatial distribution, compared to normal arc magmatism. Kinematic modelling studies have suggested that slab breakoff can account for this post-collisional magmatism through the formation of a slab window and subsequent heating of the overriding plate and decompression melting of upwelling asthenosphere, particularly if breakoff occurs at depths shallower than the overriding plate. To constrain the nature of any melting and the geodynamic conditions required, we numerically model the collision of two continental plates following a period of oceanic subduction. A thermodynamic database is used to determine the (de)hydration reactions and occurrence of melt throughout this process. We investigate melting conditions within a parameter space designed to generate a wide range of breakoff depths, timings and collisional styles. Under most circumstances, slab breakoff occurs deeper than the depth extent of the overriding plate; too deep to generate any decompressional melting of dry upwelling asthenosphere or thermal perturbation within the overriding plate. Even if slab breakoff is very shallow, the hot mantle inflow into the slab window is not sustained long enough to sufficiently heat the hydrated overriding plate to cause significant magmatism. Instead, for relatively fast, shallow breakoff we observe melting of asthenosphere above the detached slab through the release of water from the tip of the heating detached slab. Melting of the subducted continental crust during necking and breakoff is a more common feature and may be a more reliable indicator of the occurrence of breakoff. We suggest that magmatism from slab breakoff alone is unable to explain several of the characteristics of post-collisional magmatism, and that additional geodynamical processes need to be considered when interpreting magmatic observations.
DS201904-0758
2019
Maunder, B. HunenMaunder, B. Hunen, J., Bouihol, P., Magni, V.Modeling slab temperature: a reevaluation of the thermal parameter.Geochemistry, Geophysics, Geosystems, Vol. 20, 2, pp. 673-687.MantleThermometry

Abstract: We reevaluate the effects of slab age, speed, and dip on slab temperature with numerical models. The thermal parameter ? = t v sin ?, where t is age, v is speed, and ? is angle, is traditionally used as an indicator of slab temperature. However, we find that an empirically derived quantity, in which slab temperature T ? log (t?av?b) , is more accurate at depths <120 km, with the constants a and b depending on position within the slab. Shallower than the decoupling depth (~70-80 km), a~1 and b~0, that is, temperature is dependent on slab age alone. This has important implications for the early devolatilization of slabs in the hottest (youngest) cases and for shallow slab seismicity. At subarc depths (~100 km), within the slab mantle, a~1 and b~0 again. However, for the slab crust, now a~0.5 and b~1, that is, speed has the dominant effect. This is important when considering the generation of arc magmatism, and in particular, slab melting and the generation of slab?derived melange diapirs. Moving deeper into the Earth, the original thermal parameter performs well as a temperature indicator, initially in the core of the slab (the region of interest for deep water cycling). Finally, varying the decoupling depth between 40 and 100 km has a dominant effect on slab temperatures down to 140?km depth, but only within the slab crust. Slab mantle temperature remains primarily dependent on age.
DS200512-0310
2004
Maupin, V.Ganero, E.J., Maupin, V., Lay, T., Founch, M.J.Variable azimuthal anisotropy in Earth's lowermost mantle.Science, No. 5694, Oct. 8, p. 259-260.MantleGeophysics
DS200612-1064
2006
Maupin, V.Pedersen, H.A., Bruneton, M., Maupin, V., SVEKALAPKO Seismic Tomography Working GroupLithospheric and sublithospheric anisotropy beneath the Baltic Shield from surface wave array analysis.Earth and Planetary Science Letters, Vol. 244, 3-4, Apr.30, pp. 590-05.Europe, Finland, Baltic ShieldGeophysics - seismics
DS1991-1044
1991
Maurer, H.F.W.Mange, M.A., Maurer, H.F.W.Heavy minerals in colourCambridge University Press, 200p. approx. $ 90.00GlobalHeavy minerals, Descriptive -not specific to diamonds
DS202005-0763
2020
Maurer, V.C.Teixeira, W., Cordani, U.G., Faleiros, F.M., Sato, K., Maurer, V.C., Ruiz, A.S., Azevedo, E.J.P.The Rio Apa Terrane reviewed: U-Pb zircon geochronology and provenance studies provide paleotectonic links with a growing Proterozoic Amazonia.Earth Science Reviews, Vol. 202, 103089 35p. PdfSouth America, Brazilcraton

Abstract: New and compiled data of zircon U-Pb ages and geochemical-isotopic constraints provide new insights into the orogenic evolution of the Rio Apa Terrane (RAT) and its close affinity with the Amazonia throughout the Proterozoic. Two terranes with distinct evolutionary histories built the RAT. The Porto Murtinho (2070-1940 Ma) and Amoguijá (1870-1820 Ma) magmatic arcs generated the Western Terrane which is mainly composed of short-lived crustal components. Granitoid rocks (1870 Ma) in the distal Corumbá Window indicate that the RAT is much larger in extent. The Caracol accretionary arc (1800-1740 Ma) and the associated Alto Tererê back-arc basin formed away from the Amoguijá belt, being roughly coeval with the adjoining Baía das Garças suite (1776 Ma) and Paso Bravo granitoid rocks (1774-1752 Ma). These tectonic units constitute the Eastern Terrane, whilst the NdHf isotopic constraints indicate derivation from a predominantly juvenile magma source with the minor input of crustal-derived contaminants. The youngest detrital zircon grains from the Alto Tererê samples gave 1740-1790 Ma ages and unimodal age spectra were mainly present. The basin infill was, therefore, most likely concomitant with the exhumation of the Caracol belt. Alto Tererê provenance study also included detritus from passive to active margin settings. The RAT underwent regional cooling between 1.35 and 1.27 Ga, documented mainly by 40Ar39Ar and KAr ages. This age pattern matches a collisional episode that formed the accretionary margin of Amazonia, suggesting that the RAT was a close neighbor at Ectasian times. The geodynamic interplay between them lasted until 1.1 Ga ago, highlighted by some shared-components of a LIP event.
DS202108-1307
2021
Maurer, V.C.Reis, N.J., Cordani, U., Schobbenhaus, C., Maurer, V.C.New U-Pb age to the Pedra Pintada suite at the type-locality Roraima, Guiana Shield.CPRM, 1p. Abstract pdfSouth America, Venezuelacraton
DS200812-0365
2008
Maurice, C.Francis, D., Maurice, C.Ferropicrites and Archean crustal reworking in the northeastern Superior Provionce of Quebec.Goldschmidt Conference 2008, Abstract p.A281.Canada, QuebecPicrite
DS200912-0484
2009
Maurice, C.Maurice, C., Francis, D.Enriched crustal and mantle components and the role of the lithosphere in generating Paleoproterozoic dyke swarms of the Ungava Peninsula, Canada.Lithos, in press availableCanada, LabradorDykes
DS201012-0477
2010
Maurice, C.Maurice, C.Rare metal occurrences and exploration potential in Quebec.International Workshop Geology of Rare Metals, held Nov9-10, Victoria BC, Open file 2010-10, extended abstract pp.67.Canada, QuebecClassification
DS201012-0478
2010
Maurice, C.Maurice, C., Francis, D.Enriched crustal and mantle components and the role of the lithosphere in generating Paleoproterozoic dyke swarms of the Ungava Peninsula, Canada.Lithos, Vol. 114, pp. 95-108.Canada, Quebec, UngavaDykes
DS2003-0892
2003
Maurice, S.D.R.Maurice, S.D.R., Wiens, D.A., Koper, K.D., Vera, E.Crustal and upper mantle structure of southernmost South America inferred fromJournal of Geophysical Research, Vol. 08, 2, 10.1029/2001JB0001828.Asia, MantleGeophysics - seismics
DS200412-1250
2003
Maurice, S.D.R.Maurice, S.D.R., Wiens, D.A., Koper, K.D., Vera, E.Crustal and upper mantle structure of southernmost South America inferred from regional waveform inversion.Journal of Geophysical Research, Vol. 08, 2, 10.1029/2001 JB0001828.AsiaGeophysics - seismics
DS1993-0982
1993
Maurice, Y.T.Maurice, Y.T.IAGOD Symposium volume from Ottawa 1990Eigth Quadrennial Schweizerbartsche Verlag, 900pAustralia, Canada, Germany, Europe, Norway, Brazil, Russia, ChinaTectonics, paragenesis, fluid inclusions, Mineral deposits, mafics, Barite, skarn, tin, tungsten, Gold, manganese
DS1991-1079
1991
Maurin, J.C.Maurin, J.C., Boudzoumou, F., Djama, L.M., Gloan, P., Michard, A.The Proterozoic West Congolian belt and its foreland in Congo-newComptes Rendu Academy of Science Ser. II, Mec. Phys., (in French), Vol. 312, No. 11, pp. 1327-1334Central AfricaProterozoic, Geochronology
DS1993-0983
1993
Maurin, J.C.Maurin, J.C.The Pan-African West Congo belt: links with eastern Brasil and geodynamicalreconstructionInternational Geology Review, Vol. 35, No. 5, pp. 436-452Africa, Gabon, West Africa, BrazilGeodynamics, Craton
DS1991-1080
1991
Maurin, J-C.Maurin, J-C., Boudzoumou, F., Diama, L-M., Gioan, P., Michard, A.The Proterozoic of west Congolian belt and its foreland in Congo: newC.r. Academy Of Science Paris, Ser. Ii, Vol. 312, No. ser II, pp. 1327-1334Central Africa, CongoGeochronology, Structure
DS1985-0426
1985
Mauritsch, H.J.Mauritsch, H.J., Pondaga, M.H.Paleomagnetic Investigations on the East African Rift in Northern Tanzania.Journal of GEODYNAMICS, Vol. 2, No. 2-3. JUNE PP. 265-274.Central Africa, TanzaniaPaleomagnetics, Tectonics
DS1950-0146
1953
Maurois, A.Maurois, A.Cecil Rhodes: Translated from French by R. WadhamBrief Lives Publishing London United Kingdom, 405pSouth AfricaBiography
DS1950-0185
1954
Maurois, A.Maurois, A.Cecil Rhodes. #4London: Wadham, R., 140P.South AfricaKimberley, Biography
DS1950-0021
1950
Maury, G.Droogmans, H., Robert, M., Maury, G.Atlas du KatangaBruxelles: Com. Spec. Du Katanga., Democratic Republic of Congo, Central AfricaGeology, Mineral Resources
DS1998-0738
1998
Maury, R.Kepezhinskas, P., Defant, M., Maury, R., Clague, A.Composition of Island arc mantle and its bearing on the origin of cratoniclithosphere.7th International Kimberlite Conference Abstract, pp. 417-9.GlobalCraton, Subduction
DS1999-0345
1999
Maury, R.Juteau, T., Maury, R.The Oceanic crust, from accretion to mantle recyclingSpringer, 385p. approx. $ 150.00 United StatesOceanic, crustGeophysics, geodesy, Oceanic lithosphere
DS2000-0373
2000
Maury, R.Gutscher, M-A., Maury, R., Eissen, J-P., Bourdon, E.Can slab melting be caused by flat subduction?Geology, Vol. 28, No. 6, June pp. 535-8.Chile, Ecuador, Costa RicaThermometry - thermal structure, Adakites
DS2001-0951
2001
Maury, R.Prouteau, C., Scaillet, B., Maury, R.Evidence for mantle metasomatism by hydrous silicate melts derived from subducted oceanic crust.Nature, Vol. 410, No. 6825, Mar. 8, pp. 197-9.MantleMetasomatism, Subduction
DS201707-1377
2017
Maury, R.Turner, M., Turner, S., Blatter, D., Maury, R., Perfit, M., Yogodzinski, G.Water contents of clinopyroxenes from sub-arc mantle peridotitesIsland Arc, in press available 2p.Europe, Francemassif

Abstract: One poorly constrained reservoir of the Earth's water budget is that of clinopyroxene in metasomatised, mantle peridotites. This study presents reconnaissance Sensitive High-Resolution, Ion Microprobe–Stable Isotope (SHRIMP–SI) determinations of the H2O contents of (dominantly) clinopyroxenes in rare mantle xenoliths from four different subduction zones, i.e. Mexico, Kamchatka, Philippines, and New Britain (Tabar-Feni island chain) as well as one intra-plate setting (western Victoria). All of the sub-arc xenoliths have been metasomatised and carry strong arc trace element signatures. Average measured H2O contents of the pyroxenes range from 70 ppm to 510?ppm whereas calculated bulk H2O contents range from 88 ppm to 3?737?ppm if the variable presence of amphibole is taken into account. In contrast, the intra-plate, continental mantle xenolith from western Victoria has higher water contents (3?447?ppm) but was metasomatised by alkali and/or carbonatitic melts and does not carry a subduction-related signature. Material similar to the sub-arc peridotites can either be accreted to the base of the lithosphere or potentially be transported by convection deeper into the mantle where it will lose water due to amphibole breakdown.
DS1992-1014
1992
Maury, R.C.Maury, R.C., Defant, M.J., Joron, J-L.Metasomatism of the sub-arc mantle inferred from trace elements in Philippine xenolithsNature, Vol. 360, Dece, ber 17, pp. 661-663PhilippinesXenoliths, Mantle
DS1994-0972
1994
Maury, R.C.Lagabrielle, Y., la Moigne, J., Maury, R.C., Cotten, J.Volcanic record of the subduction of an active spreading ridge, Taitao Peninsula (southern Chile)Geology, Vol. 22, No. 6, June pp. 515-518ChileSubduction, Tectonics
DS2002-0331
2002
Maury, R.C.Coulon, C., Megartsi, M., Fourcade, S., Maury, R.C., Bellon, H., Louni Hacini, A.Post collisional transition from calc-alkaline to alkaline volcanism during the Neogene inLithos, Vol.62,3-4,pp. 87-110.AlgeriaSubduction - slab
DS201701-0001
2016
Maurya, N.Adhikary, D., Sahoo, R.K., Maurya, N.Petrography and geochemistry of new finding alkaline lamprophyre dyke in eastern margin of the eastern Dharwar craton, near Khammam, Telangana India.Acta Geologica Sinica, Vol. 90, 1, p. 197. abstractIndiaLamprophyre
DS201807-1491
2018
Maurya, S.Garber, J.M., Maurya, S., Hernandez, J-A., Duncan, M.S., Zeng, Li., Zhang, H.L., Faul, U., McCammon, C., Montagner, J-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L.Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere. Mentions Jericho and Roberts VictorGeochemistry, Geophysics, Geosystems, https://doi.org/10.1029/2018GCC007534Globalthermobarometry

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120?150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS201808-1745
2018
Maurya, S.Garber, J.M., Maurya, S., Hernandez, J-A., Duncan, M.S., Zeng, L., Zhang, H.L., Faul, U., McCammon, C., Montagner, J-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L.Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.G3 Geochemistry, Geophysics, Geosystems, http:/orchid.org/0000-0001-5313-0982Mantleeclogite
DS201809-2024
2018
Maurya, S.Garber, J.M., Maurya, S., Hernandez, J.A., Duncan, M.S., Zeng, L., Zhang, H.L.Multidisciplanary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.Geochemistry, Geophysics, Geosystems, Vol. 19, 7, pp. 2062-2086. doi.org/10/1029/ 2018GC007534Mantlegeophysics - seismics

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120-150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS202009-1628
2018
Maurya, S.Garber, J.M., Maurya, S., Hernandez, J.A., Duncan, M.S., Zeng, L., Zhang, H.L.Multidisciplenary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.Geochemistry, Geophysics, Geosystems, Vol. 19: https://doi.org/10.1029/2018GC007534Mantleeclogite

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120-150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS202202-0207
2021
Maurya, S.Mukherjee, S., Ray, L., Maurya, S., Shalivahan, K.P.Nature of the lithosphere boundary beneath the eastern Dharwar craton of the Indian Shield.Journal of Asian Earth Sciences, in press available 10.1016/j.jseaes.2021.105701 46 p. PdfIndiaCraton

Abstract: The lithosphere-asthenosphere boundary (LAB) is a fundamental element of the plate tectonic hypothesis that accommodates the differential motion of rigid lithosphere over the weaker asthenosphere. In recent times, various usages have been used to define the LAB, depending on the nature of their measurements. Here, we investigate the lithospheric structure beneath the Eastern Dharwar Craton (EDC) of the Indian Shield using geochemical, thermal and seismological data sets. We analysed S-receiver functions from the stations deployed in the EDC along with the surface wave dispersion tomography. We also added thermal measurements from 5 different locations and geochemical data from 34 Kimberlite/Lamproite xenolith samples to constrain the nature of the LAB. The seismological measurements using Rayleigh wave dispersion and receiver function analysis indicate the lithospheric thickness of 98-118 and 94-118 km respectively, with sharp transition across the LAB. The P-T results from xenoliths are interpreted in concurrence with the heat-flow measurements suggesting a thick thermal lithosphere of ?200 km for the normal mantle solidus with cold geotherm. To reconcile our observations, we invoke partial melts or enriched in volatiles, which significantly lowers the viscosity of mantle rocks inducing a zone of weakness between the rigid lithosphere (?125km) and the convective asthenosphere. Further, we favour the view that the thick lithosphere beneath the Indian plate has been thinned by a plume during the Gondwanaland breakup at ?130Ma. The presence of younger kimberlites from the Indian shield support that it is further degenerated by the delamination leading to an uneven topography in the LAB.
DS1999-0448
1999
Maus, S.Maus, S., Sengpiel, K.P., et al.Variogram analysis of helicopter magnetic dat a to identify paleochannels Of the Omaruru River, Namibia.Geophysics, Vol. 64, No. 3, May-June pp. 785-94.NamibiaGeophysics - magnetics, Geomorphology - not specific to diamonds
DS2003-0391
2003
Maus, S.Fairhead, J.D., Maus, S.CHAMP satellite and terrestrial magnetic dat a help define the tectonic model for SouthLeading Edge, Vol. 22, 8, pp. 779-83.South AmericaGeophysics
DS200412-0531
2003
Maus, S.Fairhead, J.D., Maus, S.CHAMP satellite and terrestrial magnetic dat a help define the tectonic model for South America and resolve the lingering problemLeading Edge, Vol. 22, 8, pp. 779-83.South AmericaGeophysics
DS200512-0420
2005
Maus, S.Hemant, K., Maus, S.Why no anomaly is visible over most of the continent ocean boundary in the global crustal magnetic field.Physics of the Earth and Planetary Interiors, Vol. 149, 3-4, April 15, pp. 321-333.MantleGeophysics - magnetics
DS200712-0426
2007
Maus, S.Hemant, K., Thebault, E., Mandea, M., Ravat, D., Maus, S.Magnetic anomaly map of the world: merging satellite, airborne, marine and ground based magnetic dat a sets.Earth and Planetary Science Letters, Vol. 260, 1-2, pp. 56-71.GlobalMap - magnetics
DS200712-0427
2007
Maus, S.Hemant, K., Thebault, E., Mandea, M., Ravat, D., Maus, S.Magnetic anomaly map of the world: merging satellite, airborne, marine and ground based magnetic dat a sets.Earth and Planetary Science Letters, Vol. 260, 1-2, pp. 56-71.GlobalMap - magnetics
DS2000-0397
2000
Mauyama, S.Hayashi, M., Komiya, T., Mauyama, S.Archean regional metamorphism of the Isua Supracrustal Belt: implications for driving force for Archean plateInternational Geology Review, Vol. 42, No. 12, Dec. 1, pp. 1055-1115.Greenland, southern WestTectonics
DS200412-1716
2004
Mauyama, S.Sachan, H.K., Mukherjee, B.K., Ogasawara, Y., Mauyama, S., Ishida, H., Muko, A., Yoshioka, N.Discovery of coesite from Indus Suture Zone (ISZ) Ladakh India: evidence for deep subduction.European Journal of Mineralogy, Vol. 16, 2, pp. 235-240.IndiaSubduction
DS200912-0757
2009
Mauz, B.Thrasher, I.M., Mauz, B., Chiverrell, R.C., Lang, A.Luminescence dating of glaciofluvial deposits: a review.Earth Science Reviews, Vol. 97, pp. 145-158.TechnologyNot specific to diamonds
DS201112-0865
2011
Mavimbela, P.K.Rigby, M.J., Basson, I.J., Kramers, J.D., Mavimbela, P.K.The structural, metamorphic and temporal evolution of the country rocks surrounding Venetia mine, Limpopo belt: evidence for a single paleoproterozoic eventPrecambrian Research, Vol. 186, 1-4, pp. 51-69.Africa, South AfricaTectonometamorphic - implications for a tectonic model
DS201112-0264
2011
MavrinDenison, V.N., Mavrin, Serebryanaya, Dubitsky, Aksenenkov, Kirichenko, Kuzmin, kulnitsky, PerehoginFirst priniples, UV Raman, X-ray diffraction and TEM study of the structure and lattic dynamics of the diamond lonsdaleite system.Diamond and Related Materials, Vol. 20, 7, pp. 951-953.TechnologyLonsdaleite
DS201802-0223
2018
Mavrin, B.N.Boldyrev, K.N., Mavrin, B.N., Sherin, P.S., Popova, M.N.Bright luminescence of diamonds with GeV centers.Journal of Luminescence, Vol. 193, pp. 119-124.Technologyluminescence

Abstract: We report on the quantum yield (?) and decay time (?) measurements at room temperature for the bright red-orange (602 nm) luminescence from new germanium-vacancy (Ge-V) centers in nano- and microcrystalline diamonds synthesized at high pressure and high temperature. The values ? = 3 ± 1% and ? = 6.2±0.2 ns were found. The Stokes shift measured as the energy difference between the maxima of the luminescence and luminescence excitation spectra is negligible. The relative intensity of the zero-phonon line constitutes up to 70% from the total intensity of the luminescence. Results of our ab initio DFT calculations for the ground-state electronic and vibrational structure of (Ge-V)? in diamond are presented and discussed.
DS202205-0674
2022
Mavrin, B.N.Boldyrev, K.N., Sedov, V.S., Vanpoucke, D.E.P., Ralchenko, V.G., Mavrin, B.N.Photoluminescence and first principles phonon study.Diamond and Related Materials, Vol. 126, 6p. PdfGlobalLuminescence
DS200812-0725
2008
Mavrin, S.A.Mavrin, S.A., Denisov, V.N., Popova, D.M., Skryleva, Kuznetsov, Nosukhin, Terentiev, Blank,V.D.Boron distribution in the subsurface region of heavily doped IIb type diamond.Physics and Chemistry of the Earth Parts A,B,C, Vol. 372, 21, pp. 3914-3918.TechnologyType IIb diamonds
DS200412-1884
2004
Mavrogenes, J.Spandler,C., Hermann, J., Arculus, R., Mavrogenes, J.Geochemical heterogeneity and element mobility in deeply subducted oceanic crust; insights from high-pressure mafic rocks from NChemical Geology, Vol. 206, 1-2, May 28, pp. 21-42.New CaledoniaSubduction, geochemistry, eclogite
DS200712-0399
2007
Mavrogenes, J.A.Hack, A.C., Hermann, J., Mavrogenes, J.A.Mineral solubility and hydrous melting relations in the deep earth: analysis of some binary A-H2O system pressure-temperature composition topologies.American Journal of Science, Vol. 307, 5, pp. 833-855.MantleMelting - water
DS201012-0531
2009
Mavrogenes, J.A.Nebel, O., Vroon, P.Z., Wiggers de Vries, D.F., Jenner, F.E., Mavrogenes, J.A.Tungsten isotopes as tracers of core mantle interactions: the influence of subducted sediments.Geochimica et Cosmochimica Acta, Vol. 74, 2, pp. 751-761.MantleSubduction
DS202010-1825
2020
Mavrogenes, J.A.Anenburg, M., Mavrogenes, J.A., Bennett, V.C.The fluorapatite P-REE-Th vein deposit at Nolans Bore: genesis by carbonatite metasomatism.Journal of Petrology, Vol. 61, 1, egaa003 42p. PdfAustralia, Northern Territorydeposit - Nolans Bore

Abstract: Nolans Bore is a rare earth element (REE) ore deposit in the Reynolds Range, Aileron Province, Northern Territory, Australia. It consists primarily of fluorapatite and alteration products thereof, surrounded by a diopside-dominated selvage. Previously considered to form via hydrothermal fluids, we now suggest that the deposit formed by a metasomatic reaction between a mantle-derived carbonatite and granulite-facies felsic host rocks, after peak metamorphism. REE patterns of fluorapatite are strongly light REE (LREE) enriched, convex with maxima at Ce to Nd, and contain a weak negative Eu anomaly. Textural and geochemical properties of the fluorapatite are consistent with its formation from a carbonatite liquid. Sinusoidal REE patterns in diopside along with strong Yb-Lu enrichment relative to coexisting titanite are suggestive of derivation from a Ca-rich carbonatite. Likewise, hyalophane present in the selvages forms by reaction of a BaCO3 component in the carbonatite with K-feldspar in the silicate host rocks. The overall morphology of Nolans Bore is consistent with carbonatite-silicate reaction experiments, with the carbonatite itself migrating elsewhere owing to the open-system nature of Nolans Bore. Ekanite veins in massive fluorapatite zones and allanite-epidote crusts on fluorapatite in contact with the diopside selvages formed by hydrothermal fluids exsolved from the carbonatite. Minor interstitial calcite was not igneous but was the last mineral to crystallize from the carbonatite-exsolved fluid. Y/Ho ratios qualitatively trace the transition from mantle-dominated igneous minerals to later low-temperature hydrothermal minerals. Rb-Sr and Sm-Nd analyses of unaltered minerals (fluorapatite, allanite, calcite) show that the carbonatite had homogeneous initial 87Sr/86Sr???0•7054 and ?Nd???-4 at 1525?Ma, the best age estimate of the mineralization. Fluorapatite-allanite Sm-Nd dating results in an age of 1446?±?140?Ma, consistent with forming soon after the end of the Chewings Orogeny. Neodymium depleted mantle model ages are older than 2?Ga, indicating the presence of recycled crustal material within the source. We suggest that the carbonatite was sourced from a mantle enriched by subduction of LREE-rich oceanic crustal rocks, marine sediments, and phosphorites, potentially from the south, or the Mount Isa area to the east. Nolans Bore represents the root zone of a now-eroded carbonatite. Other Nolans-type deposits (Hoidas Lake, Canada and Kasipatnam, India) are similarly hosted within siliceous granulite-facies rocks in regions with a long tectonic history, suggesting common processes that led to the formation of all three deposits. The REE-rich compositions of the mid-crustal Nolans Bore fluorapatite are the cumulates hypothesized to cause REE depletion in some unmineralized carbonatites. The rocks at Nolans Bore demonstrate that carbonatites, previously thought to be mostly unreactive, can undergo modification and modify the composition of the silicate rocks which they encounter, forming an ‘antiskarn’. At igneous temperatures, the resulting mineral assemblage (other than fluorapatite) consists of diopside and titanite, both of which are common in granulite-facies rocks. Therefore, carbonatite metasomatism can remain unnoticed if the resulting assemblage does not contain distinctively carbonatitic minerals.
DS202011-2027
2020
Mavrogenes, J.A.Anenburg, M., Mavrogenes, J.A., Frigo, C., Wall, F.Rare earth element mobility in and around carbonatites controlled by sodium, potassium, and silica.Science Advances, Vol. 6, 11p. 10.1126/sciadv.abb6570 pdfGlobalcarbonatites, REE

Abstract: Carbonatites and associated rocks are the main source of rare earth elements (REEs), metals essential to modern technologies. REE mineralization occurs in hydrothermal assemblages within or near carbonatites, suggesting aqueous transport of REE. We conducted experiments from 1200°C and 1.5 GPa to 200°C and 0.2 GPa using light (La) and heavy (Dy) REE, crystallizing fluorapatite intergrown with calcite through dolomite to ankerite. All experiments contained solutions with anions previously thought to mobilize REE (chloride, fluoride, and carbonate), but REEs were extensively soluble only when alkalis were present. Dysprosium was more soluble than lanthanum when alkali complexed. Addition of silica either traps REE in early crystallizing apatite or negates solubility increases by immobilizing alkalis in silicates. Anionic species such as halogens and carbonates are not sufficient for REE mobility. Additional complexing with alkalis is required for substantial REE transport in and around carbonatites as a precursor for economic grade-mineralization.
DS201911-2509
2019
Mavrogonatos, C.Baziotis, I., Xydous, S., Asimow, P.D., Mavrogonatos, C., Flemetakis, S., Klemme, S., Berndt, J.The potential of phosphorous in clinopyroxene as a geospeedometer: examples from mantle xenoliths.Geochimica et Cosmochimica Acta, Vol. 266, pp. 307-311.United States, California, Africa, Moroccometasomatism

Abstract: We investigate the potential to use concentrations and zoning patterns of phosphorus (P) in clinopyroxene as indicators of the rates of igneous and metasomatic processes, comparable to recent applications of P in olivine but applicable to more evolved rocks and lower temperatures of crystallization. Few high-P pyroxenes have been previously reported, and none have been analyzed in detail for the mechanism of P enrichment or the implications for mineral growth kinetics. Here, we report the discovery and characteristics of exotic phosphorus-rich secondary clinopyroxene in glassy pockets and veins in composite mantle xenoliths from the Cima Volcanic Field (California, USA) and the Middle Atlas Mountains (Morocco, West Africa). These glass-bearing xenoliths preserve evidence of melt infiltration events and the contrasting behavior of P in their pyroxene crystals constrains the different rates of reaction and extents of equilibration that characterized infiltration in each setting. We report optical petrography and chemical analysis of glasses and minerals for major elements by electron microprobe microanalyzer and trace elements by laser-ablation Inductively Coupled Plasma Mass Spectrometry. The Cima Volcanic Field specimen shows one end-member behavior, with unzoned P-rich clinopyroxene in a melt pocket. We attribute this occurrence to a slow crystallization process that occurred after the melt temperature reached near-equilibrium with the host rock and during which the P concentration in the melt was buffered by apatite saturation. In the Morocco xenolith, by contrast, clinopyroxene exhibits zonation with P increasing all the way to the rim, in contact with the glass. We ascribe this feature to a rapid growth process in which excess P was incorporated into the growing clinopyroxene from a diffusive boundary layer. We demonstrate quantitative agreement between the enrichment of P and other trace elements and their expected diffusion and partitioning behavior during rapid growth. We suggest that P has not been widely reported in clinopyroxene in large part because it has rarely been looked for and that its analysis offers considerable promise as a kinetic indicator both in xenoliths and volcanic rocks.
DS2003-0485
2003
Mawby, J.Goscombe, B., Hand, M., Gray, D., Mawby, J.Metamorphic architecture of a transpressional orogen: the Kaoko belt, NamibiaJournal of Petrology, Vol. 44, 4, pp. 679-712.NamibiaTectonics
DS200412-0698
2003
Mawby, J.Goscombe, B., Hand, M.,Gray, D., Mawby, J.Metamorphic architecture of a transpressional orogen: the Kaoko belt, Namibia.Journal of Petrology, Vol. 44, 4, pp. 679-712.Africa, NamibiaTectonics
DS1859-0023
1813
Mawe, J.Mawe, J.Travels in the Interior of BrasilBoston: Wells And Lilly, BrazilTravelogue
DS1986-0654
1986
Mawer, A.B.Pride, K.R., LeCouteur, P.C., Mawer, A.B.Geology and mineralogy of the Aley carbonatite, Ospika Riverarea, BritishColumbiaThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 79, No. 891, July p. 32. (abstract.)British ColumbiaCarbonatite
DS1992-1655
1992
Mawer, C.K.White, J.C., Mawer, C.K.Deep crustal deformation textures along megathrusts from Newfoundland andOntario: implications for microstructural preservation, strain rates and strength of the liCanadian Journal of Earth Sciences, Vol. 29, No. 2, Feb. pp. 328-337Newfoundland, OntarioStructure -lithosphere, Megathrusts
DS1996-0908
1996
Mawer, C.K.Mawer, C.K.Australian Proterozoic tectonicsAustralia Nat. University of Diamond Workshop July 29, 30., 1/2p.AustraliaTectonics
DS2001-0211
2001
MaxeinerCorrigan, D., Lucas, Maxeiner, Hajnal, Swanzig, SymeTectonic assembly of the Saskatchewan - Manitoba segment of the Trans Hudson Orogen.Geological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p.29, abstract.Manitoba, SaskatchewanTectonics, Trans Hudson orogeny
DS2002-0076
2002
Maxeiner, R.O.Ashton, K.E., Maxeiner, R.O., Slimmon, W.L.Sub Protereozoic Precambrian geology of southern Saskatchewan and implications for tectonic evolutionGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.3., p.3.SaskatchewanTectonics
DS2002-0077
2002
Maxeiner, R.O.Ashton, K.E., Maxeiner, R.O., Slimmon, W.L.Sub Protereozoic Precambrian geology of southern Saskatchewan and implications for tectonic evolutionGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.3., p.3.SaskatchewanTectonics
DS2002-1018
2002
Maxeiner, R.O.Maxeiner, R.O., et al.Paleoproterozoic backarc, arc and ophiolitic rocks on the northwest margin of the Trans Hudson Orogen:Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.74., p.74.SaskatchewanGeochemistry - ultramafics, harzburgite, websterite, Dykes
DS2002-1019
2002
Maxeiner, R.O.Maxeiner, R.O., et al.Paleoproterozoic backarc, arc and ophiolitic rocks on the northwest margin of the Trans Hudson Orogen:Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.74., p.74.SaskatchewanGeochemistry - ultramafics, harzburgite, websterite, Dykes
DS1989-1626
1989
Maxey, A.Wilkinson, D., Maxey, A.Diamonds are gaining more favor as a search targetRegister of Australian Mining 1989/90, pp. 297-306AustraliaOverview of exploration, Properties
DS1997-0744
1997
Maxey, M.N.Maxey, M.N.Mining ethical issues: the new prohibitionistsEngineering and Mining Journal, Vol. 198, No. 10, Oct., pp. 34-40United StatesEconomics, discoveries, Legal, environment
DS202001-0042
2019
Maximentko, N.Sumilova, T., Maximentko, N., Zubov, A., Kovalchuk, N., Ulyashev, V., Kis, V.Varieties of impactites and impact diamonds of the Kara meteorite crater ( Pay-Khoy, Russia).Geoscience Frontiers, 10.1016/j.gsf/2019.09.0111 1p. Abstract Conf.Russia, Siberiaimpact diamonds

Abstract: Impact diamonds are technical material with valuable mechanical properties. Despite of a quite long story from their discovery and huge diamond storages at the Popigai astrobleme (Siberia, Russia) they were not involved into industrial production, first of all because of remoteness of objects, complexity of extraction and economically more favourable synthesis of technical diamonds in the seventies of the past century. However, due to the high hardness of impact diamonds and also to the high demand of new carbon materials, including nanomaterials, the interest towards this type of natural diamonds is significantly increased in the recent years. Although the mentioned Popigai astrobleme is situated in a remote part of Russia it has been studied in more details. At the same time, the less known Kara giant meteorite crater (Pay-Khoy, Russia) is situated essentially closer to the industrial infrastructure of the European part of Russia. This astrobleme, similarly to Popigai, is enriched in impact diamonds as well. But, till recent years it was not deeply studied using modern analytical methods. During our studies in 2015 and 2017 at the territory of the Kara meteorite crater we have distinguished and described 5 varieties of impactites - bulk melt impactites which form cover-like and thick dike bodies; melt ultrahigh-pressure vein bodies and at least 3 types of suevites formed after specific sedimentary target rocks. These varieties have typomorphic features regarding the crystallinity and mineral composition. It was found that all of them have high concentration of microdiamonds formed by high-pressure high temperature pyrolysis mechanism from precursor materials like coal and organic relicts. Using a set of modern mineralogical methods we have found two principal types of diamond morphologies within the Kara impactites - sugar-like after coal diamonds and diamond paramorphs after organic relicts. The Kara diamonds have several accompanying carbon substances including newly formed graphite, glass-like carbon and probably carbyne. The studied diamondiferous Kara impactites provide an essentially novel knowledge of impact processes in sedimentary targets.
DS1996-1246
1996
Maximov, S.O.Sakhno, V.G., Maximov, S.O.Lamproite volcanism of the activized cratons of the Russia Far EastInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 395.RussiaLamproites
DS200412-1251
2004
Maximov, S.O.Maximov, S.O., Sakhno, V.G.High K picrites and basaltoids of the Okhotsk Massif, Russian Far East.Doklady Earth Sciences, Vol. 394, 1, Jan-Feb. pp. 32-38.RussiaPicrite
DS200812-0220
2007
Maximova, T.G.Chujkova, N.A., Nasonova, L.P., Maximova, T.G.Gravity anomalies in the Earth's crust and upper mantle.Astronomical and Astrophysical Transactions, Vol. 26, 4-5, pp. 391-399.MantleGeophysics - gravity
DS2002-1020
2002
Maxlow, J.Maxlow, J.Quantification of an Archean to recent Earth expansion process: a review of current research.The Australian Geologist, No. 122,March 31, pp. 22-27.AustraliaModel - causal, craton, global tectonics
DS1996-0909
1996
Maxson, J.Maxson, J., Tikoff, B.Hit and run collision model for the Laramide Orogeny, western UnitedStatesGeology, Vol. 24, No. 11, Nov. pp. 968-972Nevada, California, OregonTectonics, Laramide Orogeny
DS1997-0745
1997
Maxwell, P.Maxwell, P.Fly in - fly out mining education: mineral economics at the Western Australian School of MinesAustralian Institute of Mining and Metallurgy (AusIMM) Bulletin, No. 7, Nov. pp. 38-39AustraliaEconomics, discoveries
DS1991-1159
1991
Maxwell, R.J.Min Sun, Armstrong, R.L., Maxwell, R.J.Proterozoic mantle under Quesnellia: variably reset rubidium-strontium (Rb-Sr) mineral isochrons in ultramafic nodules carried up in Cenozoic volcanic vents of the s. OminecaBeltCanadian Journal of Earth Sciences, Vol. 28, No. 8, August pp. 1239-1253British ColumbiaGeochronology, Proterozoic mantle
DS1991-1081
1991
May, A.May, A.Operating system wars -the IBMpire strikes back and a Lotus 1-2-3 welldatabaseGeobyte, Vol. 6, No. 5, pp. 9-13GlobalComputer, Program -Lotus -brief overview
DS1991-1082
1991
May, A.May, A.DOS and OS/2 commandsGeobyte, Vol. 6, No. 4, August pp. 9-10GlobalComputers, Brief overview of commands -DOS/OS/2
DS1991-1083
1991
May, A.May, A.Operating environments: DOS vs. the AlternativesGeobyte, Vol. 6, No. 3, June pp. 7-10GlobalComputers, Comparison DOS etc
DS2003-0975
2003
May, D.Moresi, L., May, D., Freeman, J., Appelbe, B.Mantle convection modeling with viscoelelastic brittle lithosphere: numerical andLecture notes in Computer Science, No. 2659, pp. 781-87.MantleBlank
DS200412-1367
2003
May, D.Moresi, L., May, D., Freeman, J., Appelbe, B.Mantle convection modeling with viscoelelastic brittle lithosphere: numerical and computational methodology.Lecture notes in Computer Science, No. 2659, pp. 781-87.MantleLithosphere - model
DS200612-1370
2006
May, D.Stegman, D.R., Freeman, J., Schellart, W.P., Moresi, L.N., May, D.Evolution and dynamics of subduction zones from 4-D geodynamic models.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 58. abstract only.MantleSubduction
DS201212-0451
2012
May, D.May, D., Cordell, D., Giurco, D.Peak minerals: theoretical foundations and practical application.Natural Resources Research, Vol. 21, 1, pp. 43-60.GlobalEconomics - (oil related)
DS200912-0560
2008
May, D.A.OzBench, M., Regenauerlieb, K., Stegman, D.R., Morra, G., Farrington, R., Hale, A., May, D.A., Freeman, J.A model comparison study of large scale mantle lithosphere dynamics driven by subduction.Physics of the Earth and Planetary Interiors, Vol. 171, 1-4, pp. 224-234.MantleTectonics
DS201312-0590
2013
May, D.A.May, D.A., Schellart, W.P., Moresi, L.Overview of adaptive finite element analysis in computational geodynamics.Journal of Geodynamics, Vol. 70, Oct. pp. 1-20.TechnologyGeodynamic program
DS1995-1182
1995
May, P.M.May, P.M.CVD diamond - a new technology for the futureEndeavour, Vol. 19, No. 3, pp. 101-106. #RX948GlobalDiamond -CVD.
DS200412-0398
2003
May, P.W.Dahl, J.E.P., Moldowan, J.M., Peakman, T.M., Clardy, J.C., Lobkovsky, E., Olmstead, M.M., May, P.W., Davis, T.Isolation and structural proof of the large diamond molecule, cycloheamantane ( C26H30).Angewandte Chemie, Vol. 42, 18, pp. 2040-44.TechnologyMineral chemistry
DS200812-0726
2008
May, P.W.May, P.W.New diamond age.Science, Vol. 319, 5869, March 14, pp. 1490-1491.MantleHistory
DS202004-0497
2020
May, P.W.Ashfold, M.N.R., Goss, J.P., Green, B., May, P.W., Newton, M.E., Peaker, C.V.Nitrogen in diamond.Chemical Reviews, Vol. 120, 4, 10.1021/ acs.chemrev.9b00578 50p. PdfGlobalHPHT, CVD, synthetics

Abstract: Nitrogen is ubiquitous in both natural and laboratory-grown diamond, but the number and nature of the nitrogen-containing defects can have a profound effect on the diamond material and its properties. An ever-growing fraction of the supply of diamond appearing on the world market is now lab-grown. Here, we survey recent progress in two complementary diamond synthesis methods: high pressure high temperature (HPHT) growth and chemical vapor deposition (CVD), how each is allowing ever more precise control of nitrogen incorporation in the resulting diamond, and how the diamond produced by either method can be further processed (e.g., by implantation or annealing) to achieve a particular outcome or property. The burgeoning availability of diamond samples grown under well-defined conditions has also enabled huge advances in the characterization and understanding of nitrogen-containing defects in diamond alone and in association with vacancies, hydrogen, and transition metal atoms. Among these, the negatively charged nitrogen-vacancy (NV-) defect in diamond is attracting particular current interest in account of the many new and exciting opportunities it offers for, for example, quantum technologies, nanoscale magnetometry, and biosensing.
DS2003-0577
2003
Mayaga-Mikolo, F.Henning, A., Kiviets, G., Kurszlaukis, S., Barton, E., Mayaga-Mikolo, F.Early Proterozoic metamorphosed kimberlites from Gabon8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractGabonKimberlite petrogenesis
DS200412-0818
2003
Mayaga-Mikolo, F.Henning, A., Kiviets, G., Kurszlaukis, S., Barton, E., Mayaga-Mikolo, F.Early Proterozoic metamorphosed kimberlites from Gabon.8 IKC Program, Session 7, AbstractAfrica, GabonKimberlite petrogenesis
DS1950-0186
1954
Mayar, A.Mayar, A.L'industrie du Diamant En 1954Belg. Col. Et Comm. International Bruxelles, ANNEE LIV. Nov. 68P.GlobalDiamond Production, Mining
DS1950-0490
1959
Mayar, A.Mayar, A.The Diamond Industry 1956-1957Antwerp: Schoenmarket, Vlaams Economisch Verbond., 169P.GlobalDiamond Production, Mining
DS1991-1411
1991
Maybin, A.H.III.Reid, J.C., Mauger, R.L., Weiner, L.S., Maybin, A.H.III.Diamond-lamproite model- proposed explanation for North Carolin a and SouthCarolin a diamondsGeological Society of America Abstracts, Vol. 23, No. 1, February p. 121GlobalLamproite, Diamond genesis
DS1998-0968
1998
Mayborn, K.R.Mayborn, K.R.Petrogenesis of the Kanganiut dikes and implications for the Paleoproterozoic Nagsugtoqidian Orogen.Geological Society of America (GSA) Annual Meeting, abstract. only, p.A109.GreenlandMagmatism - dyke, Geochronology
DS2000-0636
2000
Mayborn, K.R.Mayborn, K.R., Lesher, C.E.Trace element constraints on the tectonic setting during emplacement of 2.04 Ga Kangamiut dike swarm.Geological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-376.GreenlandTectonic - history Paleoproterozoic, Laurentia
DS200412-1252
2004
Mayborn, K.R.Mayborn, K.R., Lesher, C.E.Paleoproterozoic mafic dike swarms of northeast Laurentia: products of plumes or ambient mantle?Earth and Planetary Science Letters, Vol. 225, 3-4, Sept. 15, pp. 305-317.Europe, GreenlandKangamiut swarm, REE chemistry
DS1986-0732
1986
MayedaShervais, J.W., Taylor, L.A., Lugmair, G.W., Clayton, R.N., MayedaEvolution of sub-continental mantle and crust: eclogites fromSouthernAfricaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 326-328South AfricaEclogite
DS1987-0729
1987
MayedaTaylor, L.A., Neal, C.R., Shervais, J.W., Clayton, R.N., MayedaThree types of eclogites in the Bellsbank kimberlite, S.A.crustal and mantle signaturesEos, Vol. 68, No. 44, November 3, p. 1551, abstract onlySouth AfricaBlank
DS1988-0632
1988
MayedaShervais, J.W., Taylor, L.A., Lugmair, G.W., Calyton, R.N., MayedaEarly Proterozoic oceanic crust and the evolution ofsubcontinentalmantle: eclogites and related rocks From southern AfricaGeological Society of America (GSA) Bulletin, Vol. 100, No. 3, March pp. 411-423LesothoBlank
DS1995-1791
1995
MayedaSnyder, G.A., Taylor, L.A., Jerde, E.A., Clayton, MayedaArchean mantle heterogeneity and origin of Diamondiferous eclogites:evidence hydroxyl in garnets.American Mineralogist, Vol. 80, July-Aug. No. 7-8, pp. 799-809.GlobalGeochronology, Eclogites
DS1998-1319
1998
Mayeda, T.K.Sgarbi, P.B.A., Clayton, R.N., Mayeda, T.K., Gaspar, J.Oxygen isotope thermometry of Brazilian potassic volcanic rocks of kamafugitic affinities.Chemical Geology, Vol. 146, No. 3-4, May 5, pp. 115-126.BrazilGeochronology, Alkaline rocks
DS1995-1535
1995
Mayer, A.Quick, J.E., Sinigol, S., Mayer, A.Emplacement of mantle peridotite in the lower continental crust, Ivrea-Verbano zone, northwest ItalyGeology, Vol. 23, No. 8, August pp. 739-742.ItalyPeridotite, Mantle, crust
DS201412-0563
2014
Mayer, B.Mayer, B., Jung, S., Romer, R.,Pfander, J., Klugel, A., Pack, A., Groner, E.Amphibole in alkaline basalts from intraplate settings: implications for the petrogenesis of alkaline lavas from the metasomatised lithospheric mantle.Contributions to Mineralogy and Petrology, Vol. 167, 3, pp. 1-22.MantleMetasomatism
DS1986-0156
1986
Mayer, F.Craig, M., Mayer, F.Die Diamanten Story.(in German)Geo, (in German), No. 3, March pp.11-36Southwest Africa, NamibiaOverview, Mining
DS200812-0727
2008
Mayer, S.Mayer, S.What drives iron isotope fractionation in magmas?Science, Vol. 320, 5883, June 20, p. 1600.MantleMagmatism
DS1975-1129
1979
Mayer, T.E.Mason, D.O., Mayer, T.E. , Cra exploration pty. ltd.Progress and Final Reports on Kangaroo Island, El 319, South Australia.South Australia Open File., No. E3051, 39P. UNPUBL.Australia, South AustraliaGeochemistry, Prospecting, Stream Sediment Sampling, Soil, Rock
DS201212-0191
2012
Mayers, C.Evans, N.J., McInnes, B.I.A., McDonald, B., Danisik, M., Jourdan, F., Mayers, C., Thern, E., Corbett, D.Emplacement age and thermal footprint of the Diamondiferous Ellendale E9 lamproite pipe, Western Australia.Mineralium Deposita, in press availableAustraliaDeposit - Ellendale E9
DS201212-0192
2012
Mayers, C.Evans, N.J., McInnes, B.I.A., McDonald, B., Danisik, M., Jourdan, F., Mayers, C., Thern, E., Corbett, D.Emplacement age and thermal footprint of the Diamondiferous Ellendale E9 lamproite pipe, western Australia.Mineralium Deposita, in press availableAustraliaDeposit - Ellendale E9
DS201212-0455
2012
Mayers, C.McInnes, B.I.A., Evans, N.J., Jourdan, F., McDonald, B.J., Danislk, M., Mayers, C.Zircon U-TH-PB-HE double dating of North Australian diamond fields: Ellendale(WA) Seppelt ( WA) Merlin (NT).10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAustraliaDeposit - Ellendale, Seppelt, Merlin
DS201212-0456
2012
Mayers, C.McInnis, B., Evans, N., Jourdan, F., McDonald, B., Gorter, J., Mayers, C., Wilde, S.A Tertiary record of Australian plate motion from ages of Diamondiferous alkalic intrusions.Goldschmidt Conference 2012, abstract 1p.AustraliaGeochronology - Fohn
DS201312-0252
2013
Mayers, C.Evans, N.J., McInnies, B.I.A., McDonald, B., Danisik, M., Jourdan, F., Mayers, C., Thern, E., Corbett, D.Emplacement age and thermal footprint of the Diamondiferous Ellendale E9 lamproite pipe, western Australia.Mineralium Deposita, Vol. 48, 3, pp. 413-421.AustraliaDeposit - Ellendale 9
DS201112-0561
2011
Mayewski, P.A.Kurbatov, A.V., Mayewski, P.A., Steffensen, J.P., West, A., Kennett, Bunch, Handley, Introne, Shane, Mercer etcDiscovery of a nanodiamond rich layer in the Greenland ice sheet.Journal of Glaciology, Vol. 56, no. 199, pp. 747-757.Europe, GreenlandGeomorphology
DS2003-1085
2003
Mayfield, D.Platt, J.P., Allerton, S., Kirker, A., Mandeville, C., Mayfield, D.The ultimate arc: differential displacement, oroclinal bending..Tectonics, Vol. 22,3,May, 10.1029/2001TC001321GlobalTectonics - arc
DS200412-1556
2003
Mayfield, D.Platt, J.P., Allerton, S., Kirker, A., Mandeville, C., Mayfield, D.The ultimate arc: differential displacement, oroclinal bending...Tectonics, Vol. 22,3,May, 10.1029/2001 TC001321TechnologyTectonics - arc
DS1920-0310
1926
Mayfield, S.M.Weller, S., Roberts, J.K., Mayfield, S.M.Map of the Areal and Structural Geology and Fault Patterns Of Livingston County.Kentucky Geological Survey Map, L:L MILE.Central StatesKimberlite
DS1982-0412
1982
Mayhew, M.A.Mayhew, M.A.Magsat Anomaly Field Inversion and Interpretation for the United StatesNational Technical Information Service NASA CR 169591, 67P.GlobalMid-continent, Geophysics
DS1982-0413
1982
Mayhew, M.A.Mayhew, M.A., Thomas, H.H., Wasilewski, P.J.Satellite and Surface Geophysical Expression of Anomalous Crustal structure in Kentucky and Tennessee.Earth and Planetary Science Letters, Vol. 58, PP. 395-405.GlobalMid-continent
DS1985-0427
1985
Mayhew, M.A.Mayhew, M.A., Johnson, B.D., Wasilews, P.J.A Review of Problems and Progress in Studies of Satellite Magnetic Anomalies.Journal of Geophysical Research, Vol. 90, No. 83, PP. 2511-2522.GlobalGeophysics, Remote Sensing
DS1986-0408
1986
Mayhewm M.A.Johnson, B.D., Mayhewm M.A., O'Reilly, S.Y., Griffin, W.L., ArnottMagsat anomalies, crustal magnetisation, heat flow and kimberlite occurrences in AustraliaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, Geological, No. 16, pp. 127-129AustraliaGeophysics, Magnetics
DS1986-0062
1986
Mayila, A.Basu, N.K., Mayila, A.Petrographic and chemical characteristics of the PAnd a Hillcarbonatitecomplex, TanzaniaJournal of African Earth Science, Vol. 5, No.6, pp. 589-598TanzaniaAfrica, Geochemistry
DS1983-0124
1983
Mayila, A.S.Basu, N.K., Mayila, A.S.Petrology of the PAnd a Hill Carbonatite, Mbeya Region, TanzaniaScience and Culture, Vol. 49, No. 2, pp. 44-46Central Africa, TanzaniaCarbonatite
DS1983-0437
1983
Mayman, J.Mayman, J.Diamonds in Guinea- First Stage Finances Take ShapeIndustrial Minerals, No. 187, APRIL, P. 53.Guinea, West AfricaFinance, Production
DS1986-0538
1986
Mayman, J.Mayman, J.Australia'ss new Kimberley mine-diamonds down underGoldsmith, Vol. 169, No. 4, pp. 50-54AustraliaHistory
DS1989-0963
1989
Maynard, D.E.Maynard, D.E.Terrain analysis in exploration geochemistryExplore (association Of Exploration Geochemists Newsletter), No. 65, April pp. 14, 15, 16GlobalGeochemistry, Terrains
DS1993-1557
1993
Maynard, J.B.Sutton, S.J., Maynard, J.B.Sediment and basalt hosted regoliths in the Huronian supergroup: role of parent litholohy in middle Precambrian weathering profilesCanadian Journal of Earth Sciences, Vol. 30, No. 1, January pp. 60-76OntarioWeathering, Analyses
DS1996-1390
1996
Maynard, J.B.Sutton, S., Maynard, J.B.Basement unconformity control on alteration, St. Francois Mountains, southeastMissouriJournal of Geology, Vol. 104, No. 1, pp. 55-70MissouriAlteration,, basement, St. Francois Mtns
DS1940-0123
1946
Maynard, J.E.Maynard, J.E., Ploger, L.W.An Unrecorded Dike in Syracuse, New YorkAmerican Mineralogist., Vol. 31, PP. 200-201.United States, Appalachia, New YorkRelated Rocks, Geology
DS1940-0124
1946
Maynard, J.E.Maynard, J.E., Ploger, L.W.A Study of the Salt Springs Road Peridotite Dike in Syracuse New York.American Mineralogist., Vol. 31, No. 9-10, PP. 471-485.United States, Appalachia, New YorkRelated Rocks, Petrography
DS1950-0053
1951
Maynard, J.E.Apfel, E.T., Maynard, J.E., Ploger, L.W.Possible Diatremes in Syracuse, New YorkGeological Society of America (GSA) Bulletin., Vol. 62, P. 1421. (abstract.).United States, Appalachia, New YorkRelated Rocks
DS201112-0909
2011
Maynard-Casely, H.Sanloup, C., Van Westrenen, W., Dasgupta, R., Maynard-Casely, H., Perrillat, J-P.Compressability change in iron-rich melt and implications for core formation models.Earth and Planetary Science Letters, Vol. 306, 1-2, pp. 118-122.MantleMelting
DS1975-0333
1976
Mayo, E.B.Mayo, E.B.Intrusive Fragmental Rocks Directly or Indirectly of Igneous Origin.Arizona Geol. Digest Soc., Vol. 10, PP. 347-430.GlobalBreccia
DS1994-1784
1994
Mayorova, O.Titov, A.V., Vladimirov, A.G., Chupin, V.P., Mayorova, O.Evolution and crystallization conditions of shoshonite and latite melts Kyzylrabat volcanic structure, Pamirs.Doklady Academy of Science USSR, Earth Science Section, Vol. 328, No. 1, Nov. pp. 103-107.Russia, PamirShoshonite, Alkaline rocks
DS1986-0761
1986
Mayr, U.Sobczak, L.W., Mayr, U., Sweeney, J.F.Crustal section across the polar continent, ocean transition in CanadaCanadian Journal of Earth Sciences, Vol. 23, pp. 608-21.Northwest Territories, Boothia Peninsula, Ellesmere IslandGeodynamics
DS1993-0334
1993
Mayr, U.De Frietas, T.A., Mayr, U.Middle Paleozoic tear faulting, basin development, and basement uplift central Canadian Arctic.Canadian Journal of Earth Sciences, Vol. 30, pp. 603-20.GlobalTectonics
DS1989-0903
1989
Mayrand, L.J.Ludden, J.N., Hubert, C., Mayrand, L.J., Milkereit, B., Green, A.G.Results from the lithoprobe Abitibi projectGeological Society of Canada (GSC) Forum 1989, P. 17 abstractOntarioGeophysics-seismics
DS1990-0598
1990
Mayrand, L.J.Green, A.G., Milkereit, B., Mayrand, L.J., Ludden, J.N., Hubert, C.Deep structure of an Archean greenstone terraneNature, Vol. 344, No. 6164, March 22, pp. 327-329QuebecGreenstone belt, Tectonics/structure
DS2002-0393
2002
Maza, M.Dostal, J., Caby, R., Keppie, J.D., Maza, M.Neoproterozoic magmatism in southwestern Algeria ( Sebkha el Melah Inlier): a northerly extension of the Trans Saharan orogen.Journal of African Earth Sciences, Vol. 35, 2, Aug. pp. 213-25.AlgeriaShoshonite, West African Craton
DS1991-0948
1991
Mazaud, A.Laj, C., Mazaud, A., Weeks, R., Fuller, M., Herrero Bervera, E.Geomagnetic reversal pathsNature, Vol. 351, June 6, p. 447GlobalGeophysics, Geomagnetics, Paleomagnetics
DS200812-0767
2008
Mazdab, F.Moser, D.E., Bowman, J.R., Wooden, J., Valley, J.W., Mazdab, F., Kita, N.Creation of a continent recorded in zircon zoning.Geology, Vol. 36, 3 March pp. 239-242.Canada, OntarioGeochronology - Kapuskasing
DS200612-0886
2006
Mazdab, F.K.McClelland, W.C., Power, S.E., Gilotti, J.A., Mazdab, F.K., Wopenka, B.U Pb SHRIMP geochronology and trace element geochemistry of coesite bearing zirocons, north east Greenland Caledonides.Geological Society of America, Special Paper, No. 403, pp. 23-44.Europe, GreenlandCoesite
DS200812-0132
2008
Mazdab, F.K.Bowman, J.R., Moser, D.E., Wooden, J.L., Valley, J.W., Mazdab, F.K., Kita, N.Cathodluminescence CL isotopic Pb O and trace element zoning in lower crustal zircon documents growth of early continental lithosphere.Goldschmidt Conference 2008, Abstract p.A107.Canada, OntarioKapuskasing Uplift
DS2002-0339
2002
Mazel, J.P.Crowley, J.L., Mazel, J.P., Bowring, S.A., Williams, M.L., Farmer, G.L.Paleoproterozoic to mesoproterozoic evolution of southwestern North America: the view from the lower crust.Geological Society of America Annual Meeting Oct. 27-30, Abstract p. 253.Wyoming, New MexicoDeformation, xenoliths
DS1983-0477
1983
Mazey, D.J.Nelson, R., Hudson, J.A., Mazey, D.J., Piller, R.C.Diamond Synthesis; Internal Growth During Carbon Ion ImplantationRoyal Soc. London Proceedings, Series A., Vol. 386, No. 1790, PP. 211-222.GlobalSynthesis
DS1970-0349
1971
Maziarek, S.Maziarek, S.El Mercadeo Mundial Del DiamanteCaracas Venezuela., 36P.VenezuelaKimberlite
DS1975-0129
1975
Maziarek, S.Maziarek, S.El Diamante En VenezuelaCaracas:, 129P.VenezuelaKimberlite, Kimberley, Janlib, History, Diamond
DS1993-0400
1993
Mazilov, V.N.Egorov, K.N., Bezborodov, S.M., Mazilov, V.N.Occurrence of xenoliths of volcanogenic sedimentary rocks from the Udachnaya kimberlite pipe. (Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 328, No. 3, January pp. 376-378Russia, Commonwealth of Independent States (CIS), YakutiaVolcanics, Xenoliths
DS1993-1197
1993
Mazilov, V.N.Pavlov, S.F., Kashik, S.A., Mazilov, V.N.Origin of upper Paleozoic diamond bearing placers of the Botuobin region inYakutia.(Russian)Bulletin. Mosk. Obschestva Ispyt. Prirody Otdel Geol.(Russian), Vol. 68, 3, pp. 102-108.Russia, YakutiaAlluvials, Botuobin region
DS1995-2102
1995
Mazilov, V.N.Yegorov, K.N., Bezborodov, S.M., Mazilov, V.N.Volcanogenic sedimentary xenoliths in the Udacahnaya kimberlite pipeDoklady Academy of Sciences, Vol. 329, No. 2, Jan. pp. 109-113.RussiaXenoliths, Deposit -Udachanaya
DS2003-0893
2003
Mazin, J.Mazin, J.BBX - the new over the counter market in the United StatesPdac Short Course: Comparison Of Listing Requirements For Emerging Mineral, March 12, 9p. ( slides)United StatesLegal - exchange
DS201812-2794
2018
Maziviero, M.V.Crosta, A.P., Reimold, W.V., Vasconcelos, M.A.R., Hauser, N., Oliveira, G.J.G., Maziviero, M.V., Goes, A.M.Impact cratering: the South American record. Part 2.Chemie der Erde, doi.org/10.1016/j ,chemer.2018.09.002 30MBSouth America, Brazilmeteorite

Abstract: In the first part of this review of the impact record of South America, we have presented an up-to-date introduction to impact processes and to the criteria to identify/confirm an impact structure and related deposits, as well as a comprehensive examination of Brazilian impact structures. The current paper complements the previous one, by reviewing the impact record of other countries of South America and providing current information on a number of proposed impact structures. Here, we also review those structures that have already been discarded as not being formed by meteorite impact. In addition, current information on impact-related deposits is presented, focusing on impact glasses and tektites known from this continent, as well as on the rare K-Pg boundary occurrences revealed to date and on reports of possible large airbursts. We expect that this article will not only provide systematic and up-to-date information on the subject, but also encourage members of the South American geoscientific community to be aware of the importance of impact cratering and make use of the criteria and tools to identify impact structures and impact deposits, thus potentially contributing to expansion and improvement of the South American impact record.
DS1970-0821
1973
Mazor, E.Sellschop, J.P.F., Verhagen, B.TH., Mazor, E., et al.Groundwater at Orapa, Botswana, Isotopic, Chemical and Hydrogeological Studies.Johannesburg: University Witwatersrand, Npru Report., 42P.BotswanaMining Engineering, Diamond Recovery, Kimberley
DS201902-0297
2019
Mazourel, S.Mazourel, S., Ghent, R.R., Bottke, W.F., Parker, A.H., Gernon, T.M.Earth and Moon impact flux increased at the end of the Paleozoic. Craters almost abscent older than 650 mln years. Kimberlite ages used.Science, Vol. 363, 6424, Jan. 18, pp. 253-257.Globalgeochronology
DS202002-0205
2019
Mazuera, F.Mazuera, F., Schmitz, M., Escalona, A., Zelt, C., Levander, A.Lithospheric structure of northwestern Venezuela from wide angle seismic data: implications for the understanding of continental margin evolution.Journal of Geophysical Research: Solid Earth, Vol. 124, 12, pp. 13124-131249. ( open access)South America, Venezuelageophysics - seismic

Abstract: Northwestern Venezuela is located in the complex deformation zone between the Caribbean and South American plates. Several models regarding the lithospheric structure of the Mérida Andes have been proposed. Nevertheless, they lack relevant structural information in order to support the interpretation of deeper structures. Therefore, a 560?km?long refraction profile across the northern part of Mérida Andes, oriented in a NNW direction, covering areas from the Proterozoic basement in the south, to both Paleozoic and Meso?Cenozoic terranes of northwestern Venezuela to the north, is analyzed in this contribution. Thirteen land shots were recorded by 545 short?deployment seismometers, constraining P wave velocity models from first?arrival seismic tomography and layer?based inversion covering the whole crust in detail, with some hints to upper mantle structures. The most prominent features imaged are absence of a crustal root associated to the Mérida Andes, as the Northern Andes profile is located marginal to the Andean crustal domain, and low?angle subduction of the Caribbean oceanic slab (~10-20°) beneath northwestern South America. Further crustal structures identified in the profile are (a) crustal thinning beneath the Falcón Basin along the western extension of the Oca?Ancón fault system interpreted as a back?arc basin; (b) suture zones between both the Proterozoic and Paleozoic provinces (Ouachita?Marathon?related suture?), and Paleozoic and Meso?Cenozoic terranes (peri?Caribbean suture) interpreted from lateral changes in seismic velocity; and (c) evidence of a deep Paleozoic(?) extensional basin, underlying thick Mesozoic and Cenozoic sequences (beneath the Guárico area).
DS202103-0405
2021
Mazuera, F.Schmitz, M., Ramirez, K., Mazuera, F., Avila, J., Yegres, L., Bezada, M., Levander, A.Moho depth map of northern Venezuela on wide-angle seismic studies.Journal of South American Earth Sciences, Vol. 107, 103088, 17p. PdfSouth America, VenezuelaGeophysics - seismics

Abstract: As part of the lithosphere, the crust represents Earth's rigid outer layer. Some of the tools to study the crust and its thickness are wide-angle seismic studies. To date, a series of seismic studies have been carried out in Venezuela to determine in detail the crustal thickness in the southern Caribbean, in the region of the Caribbean Mountain System in northern Venezuela, as well as along the Mérida Andes and surrounding regions. In this study, a review of the wide-angle seismic data is given, incorporating new data from the GIAME project for western Venezuela, resulting in a map of Moho depth north of the Orinoco River, which serves as the basis for future integrated models. Differences in Moho depths from seismic data and receiver function analysis are discussed. From the Caribbean plate, Moho depth increases from 20 to 25 km in the Venezuela Basin to about 35 km along the coast (except for the Falcón area where a thinning to less than 30 km is observed) and 40-45 km in Barinas - Apure and Guárico Basins, and Guayana Shield, respectively. Values of more than 50 km are observed in the Maturín Basin and in the southern part of the Mérida Andes.
DS200612-0468
2006
MazukababzovGladkochub, D.P., Wingate, M.T.D., Pisarevsky, S.A., Donskaya, T.V., Mazukababzov, Ponomarchuk, StanevichMafic intrusions in southwestern Siberia and implications for a Neoproterozoic connection with Laurentia.Precambrian Research, Vol. 147, 3-4, July 5, pp. 260-278.Russia, CanadaMagmatism
DS200912-0182
2009
Mazukabov, A.M.Donskaya, T.V., Gladkochub, D.P., Pisarevsky, S.A., Poller, U., Mazukabov, A.M., Bayanova, T.B.Discovery of Archean crust within the Akitkan orogenic belt of the Siberian craton: new insight into its architecture and history.Precambrian Research, Vol. 170, 1-2, pp. 61-72.Russia, SiberiaTectonics
DS2001-0385
2001
MazukabzovGladkochub, D.P., Sklyarov, Donskaya, MazukabzovPetrology of gabbro dolerites from Neoproterozoic dike swarms in the Sharyzhalgai block - problem breakup...Petrology, Vol. 9, No. 6, pp. 560-75.RussiaTectonics - Rodinia supercontinent, Dike swarms
DS2001-0387
2001
MazukabzovGladkochub, D.P., Sklyarov, E.V., Menshagin, MazukabzovGeochemistry of ancient ophiolites of the Sharyzhalgai upliftGeochemistry International, Vol. 39, No. 10, pp. 947-58.RussiaOphiolite - geochemistry
DS200612-0469
2006
MazukabzovGladkochub, D.P., Wingate, M.T.D., Pisarevsky, S.A., Donskaya, T.V., Mazukabzov, Ponomarchuk, StanevichMafic intrusions in southwestern Siberia and implications for a Neoproterozoic connection with Laurentia.Precambrian Research, In press, availableRussia, SiberiaGeochronology, Biryusa, magmatism
DS200512-0864
2005
Mazukabzov, A.Poller, U., Gladkochub, D., Donskaya, T., Mazukabzov, A., Sklyarov, E., Todt, W.Multistage magmatic and metamorphic evolution in the southern Siberian craton: Archean and paleoproterozoic zircon ages revealed by SHRIMP and TIMS.Precambrian Research, Vol. 136, 3-4, pp. 353-368.Russia, SiberiaGeochronology
DS200612-0467
2006
Mazukabzov, A.Gladkochub, D., Pisarevsky, S., Donskaya, L., Mazukabzov, A., Stanevich, A., Sklyarov, E.Siberian Craton and its evolution in terms of Rodinia hypothesis.Episodes, Vol. 29, 3, pp. 169-174.Russia, SiberiaCraton, genesis
DS2002-0578
2002
Mazukabzov, A.M.Gladkochub, D.P., Donskaya, T.V., Mazukabzov, A.M., Sklyarov, E.V.The Urik Iya graben of the Sayan In lier of the Siberian Craton: new geochronologicalDoklady Earth Sciences, Vol. 386, 7, Sept-Oct.pp. 737-41.Russia, SiberiaGeochronology, Geodynamics, tectonics - not specific to diamonds
DS2002-1505
2002
Mazukabzov, A.M.Sklyarov, E.V., Gladkochub, D.P., Mazukabzov, A.M., Donskaya, T.V.Geological complexes in the margin of the Siberian Craton as indicators of the evolutionRussian Journal of Earth Science, Vol. 4, 3, JuneRussiaMagmatism, Gondwana
DS2003-1290
2003
Mazukabzov, A.M.Sklyarov, E.V., Gladkochub, D.P., Mazukabzov, A.M., Menshagin, Y.V.Neoproterozoic mafic dike swarms of the Sharyzhalgai metamorphic massif, southernPrecambrian Research, Vol. 122, 1-4, pp.359-76.Russia, SiberiaDyke swarms, Magmatism
DS200412-1484
2004
Mazukabzov, A.M.Ota, T., Gladkochub, D.P., Skylarov, E.V., Mazukabzov, A.M., Watanabe, T.P T history of garnet websterites in the Sharyzhalgai complex, southwestern margin Siberian Craton: evidence from PaleproterozoiPrecambrian Research, Vol. 132, 4, pp. 327-348.Russia, SiberiaMetamorphism
DS200412-1847
2003
Mazukabzov, A.M.Sklyarov, E.V., Gladkochub, D.P., Mazukabzov, A.M., Menshagin, Y.V., Watanabe, T., Pisarevsky, S.A.Neoproterozoic mafic dike swarms of the Sharyzhalgai metamorphic massif, southern Siberian craton.Precambrian Research, Vol. 122, 1-4, pp.359-76.Russia, SiberiaDyke swarms Magmatism
DS200512-0865
2005
Mazukabzov, A.M.Poller, U., Gladkochub, D.P., Donskaya, T.V., Mazukabzov, A.M., Sklyarov, E.V., Todt, W.Timing of Early Proterozoic magmatism along the southern margin of the Siberian Craton ( Kitoy area).Geological Society of America Special Paper, No. 389, pp. 215-226.RussiaMagmatism ( not specific to diamonds)
DS200712-0363
2007
Mazukabzov, A.M.Gladkochub, D.P., Donskaya, T.V., Mazukabzov, A.M., Stanevich, A.M., Sklyarov, E.V., Ponomarchuk, V.A.Signature of Precambrian extension events in the southern Siberian Craton.Russian Geology and Geophysics, Vol. 48, pp. 17-31.RussiaDike swarm, rifting, Rodinia
DS200712-0847
2006
Mazukabzov, A.M.Pisarevsky, S.A., Gladkochub, D.P., Donskaya, T.A., De Waeel, B., Mazukabzov, A.M.Paleomagnetism and geochronology of mafic dykes in south Siberia, Russia: the first precisely dated Permian paleomagnetic pole from the Siberian Craton.Geophysical Journal International, Vol. 167, 2, pp. 649-658.RussiaGeochronology
DS200812-0413
2008
Mazukabzov, A.M.Gladkochub, D.P., Sklyarov, E.V., Donskaya, T.V., Stanevich, A.M., Mazukabzov, A.M.A period of global uncertainty ( Blank spot) in the Precambrian history of the southern Siberian Craton and the problem of the transproterozoic supercontinent.Doklady Earth Sciences, Vol. 421, 1, pp. 774-778.Russia, SiberiaTectonics
DS201012-0236
2010
Mazukabzov, A.M.Gladkochub, D.P., Pisarevsky, S.A., Ernst, R., Donskaya, T.V., Soderlund, U., Mazukabzov, A.M., Hanes, J.Large igneous province of about 1750 Ma in the Siberian Craton.Doklady Earth Sciences, Vol. 430, 2, pp. 163-167.RussiaMagmatism
DS201312-0315
2013
Mazukabzov, A.M.Gladkochub, D.P., Kostrovitskii, S.I., Donskaya, T.V., De Waele, B., Mazukabzov, A.M.Age of zircons from diamond bearing lamproites of the East Sayan as an indicator of known and unkonwn endogenous events in the south Siberian craton.Doklady Earth Sciences, Vol. 450, 2, June pp. 597-601.Russia, SayanLamproite
DS201712-2686
2017
Mazukabzov, A.M.Gladkochub, D.P., Donskaya, T.V., Sklyarov, E.V., Kotov, A.B., Vladykin, N.V., Pisarevsky, S.A., Larin, A.M., Salnikova, E.B., Saveleva, V.B., Sharygin, V.V., Starikova, A.E., Tolmacheva, E.V., Velikoslavinsky, S.D., Mazukabzov, A.M., Bazarova, E.P., KovaThe unique Katugin rare metal deposit ( southern Siberia): constraints on age and genesis.Ore Geology Reviews, in press available, 18p.Russia, Siberiadeposit - Katugin

Abstract: We report new geological, mineralogical, geochemical and geochronological data about the Katugin Ta-Nb-Y-Zr (REE) deposit, which is located in the Kalar Ridge of Eastern Siberia (the southern part of the Siberian Craton). All these data support a magmatic origin of the Katugin rare-metal deposit rather than the previously proposed metasomatic fault-related origin. Our research has proved the genetic relation between ores of the Katugin deposit and granites of the Katugin complex. We have studied granites of the eastern segment of the Eastern Katugin massif, including arfvedsonite, aegirine-arfvedsonite and aegirine granites. These granites belong to the peralkaline type. They are characterized by high alkali content (up to 11.8?wt% Na2O?+?K2O), extremely high iron content (FeO?/(FeO??+?MgO)?=?0.96-1.00), very high content of most incompatible elements - Rb, Y, Zr, Hf, Ta, Nb, Th, U, REEs (except for Eu) and F, and low concentrations of CaO, MgO, P2O5, Ba, and Sr. They demonstrate negative and CHUR-close ?Nd(t) values of 0.0…?1.9. We suggest that basaltic magmas of OIB type (possibly with some the crustal contamination) represent a dominant part of the granitic source. Moreover, the fluorine-enriched fluid phases could provide an additional source of the fluorine. We conclude that most of the mineralization of the Katugin ore deposit occurred during the magmatic stage of the alkaline granitic source melt. The results of detailed mineralogical studies suggest three major types of ores in the Katugin deposit: Zr mineralization, Ta-Nb-REE mineralization and aluminum fluoride mineralization. Most of the ore minerals crystallized from the silicate melt during the magmatic stage. The accessory cryolites in granites crystallized from the magmatic silicate melt enriched in fluorine. However, cryolites in large veins and lens-like bodies crystallized in the latest stage from the fluorine enriched melt. The zircons from the ores in the aegirine-arfvedsonite granite have been dated at 2055?±?7?Ma. This age is close to the previously published 2066?±?6?Ma zircon age of the aegirine-arfvedsonite granites, suggesting that the formation of the Katugin rare-metal deposit is genetically related to the formation of peralkaline granites. We conclude that Katugin rare-metal granites are anorogenic. They can be related to a Paleoproterozoic (?2.05?Ga) mantle plume. As there is no evidence of the 2.05?Ga mantle plume in other areas of southern Siberia, we suggest that the Katugin mineralization occurred on the distant allochtonous terrane, which has been accreted to Siberian Craton later.
DS202102-0194
2021
Mazukabzov, A.M.Gladkochub, D.P., Donskaya, T.V., Pisarevesky, S.A., Salnikova E.B., Mazukabzov, A.M., Kotov, A.B., Motova, Z.I., Stepanova, A.V., Kovach, V.P.Evidence of the latest Paleoproterozoic ( ~1615 Ma) mafic magmatism the southern Siberia: extensional environments in Nuna subcontinent.Precambrian Research, Vol. 354, doi.org/10.1016 /j.precamres. 2020.10049 14p. PdfRussiaCraton - Siberian
DS2001-0386
2001
Mazukabzov, et al.Gladkochub, D.P., Sklyarov, Donskaya, Mazukabzov, et al.Petrology of gabbro dolerites from Neoproterozoic dike swarms in Sharyzhalgai Block with reference to problemPetrology, Vol.9, 6, pp. 560-75.Russia, SiberiaCraton - breakup of the Rodinia supercontinent, Magma - melt
DS201012-0719
2009
Mazukebzov, A.M.Sklyarov, E.V., Fedorovsky, V.S., Kotov, A.B., Lavrenchuk, A.V., Mazukebzov, A.M., Levitsky, V.I., et al.Carbonatites in collisional settings and pseudo-carbonatites of the Early Paleozoic Olkhon collisional system.Russian Geology and Geophysics, Vol. 50, 12, pp. 1091-1106.RussiaTectonics
DS2000-0637
2000
Mazumder, R.Mazumder, R., Bose, P.K., Sarkar, S.A commentary on the tectono sedimentary record of the pre 2.0 Ga continental growth of India vis a vis ...Journal of African Earth Sciences, Vol. 30, No. 2, Feb. pp. 201-18.IndiaGondwana Afro-India supercontinent, Tectonics
DS2000-0638
2000
Mazumder, R.Mazumder, R., Bose, P.K., Sarkar, S.A commentary of the tecton-sedimentary record of pre 2.0 Ga continental growth of India..vis a vis pre-Journal of African Earth Sciences, Vol. 30, No. 2, pp. 201-17.IndiaTectonics - Gondwana Afro-Indian supercontinent
DS200712-0296
2006
Mazumder, R.Eriksson, P.G., Mazumder, R., Catuneanu, O., Bumby, A.J., Ilondo, B.O.Precambrian continental free board and geological evolution: a time perspective. Kaapvaal, Pilbara, SinghbhumEarth Science Reviews, in press availableMantle, South Africa, Australia, IndiaContinent freeboard, crustal growth, thickness, plumes
DS200912-0619
2009
Mazumder, R.Reddy, S.M., Mazumder, R., Evans, D.A.D., Collins, A.S.Paleoproterozoic supercontinents and global evolution.Geological Society of London Special Publication, www.geolsoc.org.uk/bookshopGlobalBook
DS202009-1626
2011
Mazumder, R.Eriksson, P.G., Lenhardt, N., Wright, D.T., Mazumder, R., Bumby, A.J.Late Neoarchean-paleoproterozoic supracrustal basin-fills of the Kaapvaal craton: relevance of the supercontinent cycle, the "Great Oxidation Event" and "Snowball Earth?". Note Date*** glaciationMarine and Petroleum Geology, Vol. 28, pp. 1385-1401.Africa, South Africageomorphology

Abstract: The application of the onset of supercontinentality, the “Great Oxidation Event” (GOE) and the first global scale glaciation in the Neoarchaean-Palaeoproterozoic as panacea-like events providing a framework or even chronological piercing points in Earth’s history at this time, is questioned. There is no solid evidence that the Kaapvaal craton was part of a larger amalgamation at this time, and its glacigenic record is dominated by deposits supporting the operation of an active hydrological cycle in parallel with glaciation, thereby arguing against the “Snowball Earth Hypothesis”. While the Palaeoproterozoic geological record of Kaapvaal does broadly support the GOE, this postulate itself is being questioned on the basis of isotopic data used as oxygen-proxies, and sedimentological data from extant river systems on the craton argue for a prolongation of the greenhouse palaeo-atmosphere (possibly in parallel with a relative elevation of oxygen levels) which presumably preceded the GOE. The possibility that these widespread events may have been diachronous at the global scale is debated.
DS2003-0894
2003
Mazunder, R.Mazunder, R.Correlations between the Eastern Block of the North Chin a Craton and the SouthPrecambrian Reserach, Vol. 127,4, pp. 379-80.China, IndiaTectnics
DS200412-1253
2003
Mazunder, R.Mazunder, R.Correlations between the Eastern Block of the North Chin a Craton and the South Indian Block of the Indian Shield: an Archean toPrecambrian Reserach, Vol. 127,4, pp. 379-80.China, IndiaTectonics
DS201212-0452
2012
Mazunder, R.Mazunder, R., Saha, D.Paleoproterozoic of India.Geological Society of London Special Publication, no. 365, 300p.IndiaBook - paleoproterozoic
DS2000-0115
2000
Mazur, T.R.Brown, P.G., Hildebrand, A.R., Mazur, T.R.The fall, recovery, orbit and composition of the Taglish Lake meteorite: A new type of carbonaceous..Science, Vol. 290, No. 5490, Oct. 13, pp. 320-4.Northwest TerritoriesChondrites
DS200712-1111
2007
Mazurov, M.P.Vasilev, Y.R., Prusskaya, S.N., Mazurov, M.P.A new type of large scale manifestation of within plate intrusive trap magmatism.Doklady Earth Sciences, Vol. 413, 2, pp. 187-191.RussiaMagmatism
DS200812-0432
2008
Mazurov, M.P.Grishina, S.N., Polozov, A.C., Mazurov, M.P., Titov, A.T.Origin of chloride xenoliths of Udachnaya East kimberlite pipe, Siberia: evidence from fluid and saline melt inclusions.9IKC.com, 3p. extended abstractRussia, SiberiaDeposit - Udcahnaya inclusions
DS201012-0686
2009
Mazurov, M.P.Sharapov, V.N.,Chudnenko, K.V., Mazurov, M.P., Perepechko, Yu.V.Metasomatic zoning of subduction lithosphere in Siberia: physiochemical modeling.Russian Geology and Geophysics, Vol. 50, 12, pp. 1107-1118.Russia, SiberiaSubduction
DS201112-0940
2011
Mazurov, M.P.Sharapov, V.N., Mazurov, M.P., Tomilenko, A.A., Faleev, V.A.Mass transfer in garnet ultramafic xenoliths subject to partial melting under hot reduced gas flows.Russian Geology and Geophysics, Vol. 52, pp. 165-177.Russia, YakutiaDeposit - Udachnaya Vostochnaya
DS201412-0316
2014
Mazurov, M.P.Grishina, S.N., Polozov, A.G., Mazurov, M.P., Goryinov, S.V.Genesis of chloride-carbonate segregations of the Udachnaya-East pipe.Doklady Earth Sciences, Vol. 458, 1, pp. 1129-1131.Russia, YakutiaDeposit - Udachnaya-East
DS1981-0257
1981
Mazykin, V.V.Kvasnitsa, V.N., Mazykin, V.V., Matyash, I.V., Tsymbal, S.N.(epa Spectra of Small Natural Diamonds and Their Possible Geneticificance.)Mineral. Zhur., Vol. 3, No. 1, PP. 89-92.RussiaKimberlite
DS1986-0539
1986
Mazykin, V.V.Mazykin, V.V., Mattyash, I.V., Kvasnitska, V.N., Argunov, K.P., ZinchukESR spectra of neutron irradiated diamonds.(Russian)Dopl. Akad. Nauk UKR. B.Geol, (Russian), No. 10, pp. 10-12GlobalMineralogy
DS1987-0036
1987
Mazykin, V.V.Bartoshinskii, Z.V., Matyash, I.V., Mazykin, V.V., Bekesha, S.N.Major nitrogen paramagnetic centers in diamonds from placers of northeastern Siberian PlatformMineral. Zhurn., (Russian), Vol. 9, No. 3, pp. 87-89RussiaBlank
DS201412-0410
2014
Mazzarini, F.Isola, I., Mazzarini, F., Bonini, M., Corti, G.Spatial variability of volcanic features in early stage rift settings: the case of the Tanzania divergence, East African rift system.Terra Nova, in press availableAfrica, TanzaniaTectonics
DS201412-0752
2014
Mazzarini, F.Rooney, T.O., Bastow, I.D., Keir, D., Mazzarini, F., Movsesian, E., Grosfils, E.B., Zimbelman, J.R., Ramsey, M.S., Ayalew, D., Yirgu, G.The protracted development of focused magmatic intrusion during continental rifting.Tectonics, Vol. 33, 6, pp. 875-897.Africa, EthiopiaPrecambrian lineaments
DS201502-0065
2014
Mazzarini, F.Isola, I., Mazzarini, F., Bonini, M., Cortiz, G.Spatial variability of volcanic features in early-stage rift settings: the case of the Tanzanian divergence, East African Rift.Terra Nova, Vol. 26, pp. 461-468.Africa, TanzaniaRifting, magmatism
DS202103-0393
2021
Mazzero, F.C.Mazzero, F.C., Rocco, I., Tucker, R.D., Morra, V., D'Antonio, M., Melluso, L.Olivine melilitites, mantle xenoliths, and xenocrysts of the Takarindiona district: petrogenesis, magmatic evolution, and the sub-continental lithospheric mantle of east-central Madagascar.Journal of African Earth Sciences, Vol. 174, 104059, 17p. PdfAfrica, Madagascarmelilitites

Abstract: The olivine melilitites from the southern part of the 6.8 Ma-old Takarindiona volcanic field (Eastern Madagascar) are olivine ± chromite -phyric lavas, with zoned titanaugite, perovskite, melilite, nepheline, monticellite, Ba-Ti-mica and Fe-Ti oxides as microphenocrysts and groundmass phases. The rocks are very primitive, rich in incompatible trace elements (e.g., Ba = 1049 ± 153 ppm, Sr = 1050 ± 167 ppm, Nb = 98 ± 13 ppm; La/Ybn = 41 ± 5; La/Nb = 0.88 ± 0.05), and have restricted ranges of initial 87Sr/86Sr (0.70391-0.70410) and 143Nd/144Nd (0.51272-0.51282). The rocks follow a differentiation trend controlled by ab. 20% removal/addition of phenocryst olivine ± chromite. The olivine melilititic magmas are the product of small degrees of partial melting (1-3%) of a peridotitic source, enriched in highly incompatible trace elements by CO2-, F-, and H2O-rich melts, located within the garnet stability field (3-3.5 GPa and ~100 km depth) of sub-continental lithospheric mantle, where carbonates (dolomite) and possibly phlogopite were stable phases. Mantle xenoliths within the volcanics are mostly spinel harzburgites having mineral modes and chemical compositions suggesting variable degrees of "basalt" melt extraction. Based on textural and chemical evidence, and quantitative thermobarometric estimates, the xenoliths were incorporated at a pressure of ~1.1 GPa (~35-40 km depth), far shallower than the source of the melilititic magmas, and along a predictably cool geotherm beneath Archean continental lithosphere. Highly resorbed orthopyroxene xenocrysts mantled by augite indicate that the melilitites may have also entrained lower crustal materials or underplated subalkaline rocks. The mantle sources of the lavas and mantle xenoliths of the Takarindiona district indicate stratification of the lithospheric mantle, and help constraining the lithospheric features and the magmatic history of the Eastern Madagascar craton.
DS1996-0252
1996
Mazzoli, S.Cello, G., Mazzoli, S.Kinematics of primary contacts between low and relatively high pressure rocks in orogensJournal of Structural Geology, Vol. 18, No. 4, Apr.1, pp. 519-522GlobalStructure, metamorphism
DS1986-0540
1986
Mazzone, P.Mazzone, P., Haggerty, S.E.Corganites and corgaspinites. Two new types of aluminous assemblages From the Jagersfontein kimberlite pipeProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 279-281South AfricaPetrography, Mineral chemistry
DS1987-0449
1987
Mazzone, P.Mazzone, P., McLanahan, A., Haggerty, S.E.Clinopyroxene megacrysts from the Jagersfontein kimberlite pipeEos, abstractSouth AfricaPetrology
DS1988-0448
1988
Mazzone, P.Mazzone, P.Petrography, mineral chemistry and geochemistry of peraluminous xenoliths from the JagersfonteinkimberlitePh.d. thesis, University of Massachusetts, 232pSouth AfricaPetrography Jagersfontein, Geochemistry
DS1989-0964
1989
Mazzone, P.Mazzone, P., Haggerty, S.E.Peraluminous xenoliths in kimberlite: metamorphosed restites produced by partial melting of pelitesGeochimica et Cosmochimica Acta, Vol. 53, pp. 1551-1561South AfricaJagersfontein, Xenoliths
DS1989-0965
1989
Mazzone, P.Mazzone, P., Haggerty, S.E.Corganites and coraspinites: two new types of aluminous assemblages From the Jagersfontein kimberlite pipeGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 795-808South AfricaXenoliths, Mineral chemistry
DS1996-1058
1996
Mazzoni, M.M.Ort, M.H., Coira, B.L., Mazzoni, M.M.Generation of a crust mantle magma mixture: magma sources and contaminationat Cerro PanizosContributions to Mineralogy and Petrology, Vol. 123, pp. 308-322Argentina, Bolivia, AndesIgnimbrite
DS201709-2043
2017
Mazzoni, M.S.C.Pimenta Martins, L.G., Matos, M.J.S., Paschoal, A.R., Freire, P.T.C., Andrade, N.F., Aguiar, A.L., Kong, J., Neves, B.R.A., de Oliveira, A.B., Mazzoni, M.S.C., Souza Filhio, A.G., Cancad, L.G.Raman evidence for pressure induced formation of diamondene.Nature Communications, Vol. 8, 9p.Technologydiamondene

Abstract: Despite the advanced stage of diamond thin-film technology, with applications ranging from superconductivity to biosensing, the realization of a stable and atomically thick two-dimensional diamond material, named here as diamondene, is still forthcoming. Adding to the outstanding properties of its bulk and thin-film counterparts, diamondene is predicted to be a ferromagnetic semiconductor with spin polarized bands. Here, we provide spectroscopic evidence for the formation of diamondene by performing Raman spectroscopy of double-layer graphene under high pressure. The results are explained in terms of a breakdown in the Kohn anomaly associated with the finite size of the remaining graphene sites surrounded by the diamondene matrix. Ab initio calculations and molecular dynamics simulations are employed to clarify the mechanism of diamondene formation, which requires two or more layers of graphene subjected to high pressures in the presence of specific chemical groups such as hydroxyl groups or hydrogens.
DS2002-1021
2002
Mazzotti, S.Mazzotti, S., Dragert, Hyndman, Miller, HentonGPS deformation in a region of high crustal seismicity: N. Cascadia forearcEarth and Planetary Science Letters, Vol.198,1-2,pp.41-8., Vol.198,1-2,pp.41-8.CordilleraGeophysics - seismics not specific to diamonds
DS2002-1022
2002
Mazzotti, S.Mazzotti, S., Dragert, Hyndman, Miller, HentonGPS deformation in a region of high crustal seismicity: N. Cascadia forearcEarth and Planetary Science Letters, Vol.198,1-2,pp.41-8., Vol.198,1-2,pp.41-8.CordilleraGeophysics - seismics not specific to diamonds
DS200612-0615
2006
Mazzotti, S.Hyndman, R.D., Fluck, P., Mazzotti, S., Lewis, T.J., Ristau, J., Leonard, L.Current tectonics of the northern Canadian Cordillera.Canadian Journal of Earth Sciences, Vol. 42, 6, pp. 1117-1136.Canada, British ColumbiaTectonics
DS2001-0657
2001
Mazzucchelli, M et al.Laurora, A., Mazzucchelli, M et al.Metasomatism and melting in carbonated peridotite xenoliths from the mantle wedge: Gobernador GregoresJournal of Petrology, Vol. 42, No. 1, Jan. pp. 69-88.GlobalMetasomatism - xenoliths
DS1992-1015
1992
Mazzucchelli, M.Mazzucchelli, M., Rivalenti, G., Vannucci, R., Bottazzi, P.Trace element distribution between clinopyroxene and garnet in gabbroicGeochimica et Cosmochimica Acta, Vol. 56, pp. 2371-2385ItalyCrust, Mafic-ultramafic, Garnet, clinopyroxene
DS1995-1183
1995
Mazzucchelli, M.Mazzucchelli, M., Rivalenti, G.Petrology of the Proterozoic mafic dyke swarms of Uruguay and constraints on their mantle source...Precambrian Research, Vol. 74, No. 3, Aug. 15, pp. 177-UruguayDyke swarms, Magmatism
DS1996-0533
1996
Mazzucchelli, M.Girardi, A., Mazzucchelli, M., Correia, C.T.Petrology and geochemistry of the mafic dyke swarm of the Treinte Y Tresregion, northeast Uruguay.Journal of South American Earth Sciences, Vol. 9, No. 3/4, pp. 243-250.UruguayDike swarm, Petrology
DS1998-1241
1998
Mazzucchelli, M.Rivalenti, G., Mazzucchelli, M., Teixeira, W.Petrogenesis of the Paleoproterozoic basalt andesite rhyolite dyke association in Carajas regionLithos, Vol. 43, No. 4, Sept. 1, pp. 235-266Peru, ArgentinaAmazonia Craton, Dyke swarm
DS1999-0823
1999
Mazzucchelli, M.Zanetti, A., Mazzucchelli, M., Vanucci, R.The Finero phlogopite peridotite massif: an example of subduction relatedMetasomatismContributions to Mineralogy and Petrology, Vol. 134, No. 2-3, pp. 107-122.ItalyMetasomatism, perioditite
DS200412-1674
2004
Mazzucchelli, M.Rivalenti, G., Zanetti, A., Mazzucchelli, M., Vanucci, R., Congolani, C.A.Equivocal carbonatite markers in the mantle xenoliths of the Patagonia backarc: the Gobernador Gregores case ( Santa Cruz ProvinContributions to Mineralogy and Petrology, Vol. 147, 6, pp. 647-670.South America, ArgentinaCarbonatite
DS200512-0907
2004
Mazzucchelli, M.Rivalenti, G., Mazzucchelli, M., Laurora, A., Ciuffi, S.I.A., Zanetti, A., Vannucci, R., Cingolani, C.A.The backarc mantle lithosphere in Patagonia, South America.Journal of South American Earth Sciences, Vol. 17, 2, Oct. 30, pp. 121-152.South America, PatagoniaXenoliths, geothermometry, melting, slab, subduction
DS200612-1164
2006
Mazzucchelli, M.Rivalenti, G., Zanetti, A., Giradri, V.A.V., Mazzucchelli, M., Tassinari, C.G., Bertotto, G.W.The effect of the Fernando de Noronha plume on the mantle lithosphere in north eastern Brazil.Lithos, in press available,South America, BrazilXenoliths, alkali basalts, geochemistry
DS200712-0897
2006
Mazzucchelli, M.Rivalenti, G., Zanetti, A., Girardi, V.A.V., Mazzucchelli, M., Colombo, C.G., Bertotto, G.W.The effect of the Fernando de Noronha plume on the mantle lithosphere in north eastern Brazil.Geochimica et Cosmochimica Acta, In press availableSouth America, BrazilXenolith - alkali basalt
DS201612-2342
2016
Mazzucchelli, M.Teixeira, W., Girardi, V.A.V., Mazzucchelli, M., Oliveira, E.P., Correa da Costa, P.C.Precambrian dykes in the Sao Francisco craton revisited: geochemical-isotopic signatures and tectonic significance.Acta Geologica Sinica, Vol. 90, July abstract p. 26-27.South America, Brazil, DiamantinaGeochronology
DS201705-0830
2017
Mazzucchelli, M.Giovanardi, T., Girardi, V.A.V., Correia, C.T., Sinigoi, S., Tassinari, C.C.G., Mazzucchelli, M.The growth and contamination mechanism of the Cana Brava layered mafic-ultramafic complex: new field and geochemical evidences.Mineralogy and Petrology, in press available 24p.South America, BrazilGeochemistry

Abstract: The Cana Brava complex is the northernmost of three layered complexes outcropping in the Goiás state (central Brasil). New field and geochemical evidences suggest that Cana Brava underwent hyper- to subsolidus deformation during its growth, acquiring a high-temperature foliation that is generally interpreted as the result of a granulite-facies metamorphic event. The increase along the stratigraphy of the incompatible elements abundances (LREE, Rb, Ba) and of the Sr isotopic composition, coupled with a decrease in ?Nd(790), indicate that the complex was contaminated by the embedded xenoliths from the Palmeirópolis Sequence. The geochemical data suggest that the contamination occurred along the entire magma column during the crystallization of the Upper Mafic Zone, with in situ variations determined by the abundance and composition of the xenoliths. These features of the Cana Brava complex point to an extremely similarity with the Lower Sequence of the most known Niquelândia intrusion (the central of the three complexes). This, together with the evidences that the two complexes have the same age (c.a. 790 Ma) and their thickness and units decrease northwards suggests that Cana Brava and Niquelândia are part of a single giant Brasilia body grown through several melt impulses.
DS201904-0718
1991
Mazzucchelli, M.Bossi, J., Campal, N., Civetta, L., Demarchi, G., Girardi, V.V., Mazzucchelli, M., Piccirillo, E.M., Rivalenti, G., Sinigol, S., Teixeira, W., Fragoso-Cesar, A.R.Petrological and geochronological aspects of the Precambrian mafic dyke swarm of Uruguay. IN: Eng. Note Date****BOL.IG-USP, Publ.Esp., Vol. 10, pp. 35-42.South America, Uruguaydykes

Abstract: The subparallel maflc dykes of the Aorida-Durazno-S.José region (SW Uruguay) trend N60-80W and vary in thickness from 0.6 to 50 m. They are part of the mafic dyke swarms intrudlng granitic-gnelssic basement that were mappecl by BOSSI et ai. (1989), In an ares approximately 200 km In length and 100 km in bresdth. Plagioclass, augite, subcalclc augite (plgeonite) and opaques are the maln components of the dykes. Orthopyroxene and oIlvine are very rare. Blotite and homblende are secondary minerais. Quartz-feldspar Intergrowths occur In the coarser gralnecl dykes. The characterlstlc textures are subophitic and intersertal.
DS201904-0740
2019
Mazzucchelli, M.Giovanardi, T., Girardi, V.A.V., Teixeira, W., Mazzucchelli, M.Mafic dyke swarms at 1882, 535 and 200 Ma in the Carajas region Amazonian Craton: Sr-Nd isotopy, trace element geochemistry and inferences on their origin and geological settings.Journal of South American Earth Sciences, Vol. 92, pp. 197-208.South America, Brazilcraton

Abstract: The Carajás-Rio Maria region, together with the Rio Maria domain of the Central Amazonian province, comprises the eastern margin of the Amazonian Craton with the Neoproterozoic Araguaia belt. This region hosts several basaltic dyke swarms whose UPb baddeleyite ages highlighted three intrusive events at 1882, 535 and 200?Ma. New geochemical and SrNd isotopic data were obtained for the different groups of the Carajás dykes allowing new insights on i) the mantle source composition beneath the Carajás region through time and ii) the geodynamic setting of the intrusive events. The 1882?Ma swarm is coeval to the Uatumã SLIP event which is one of the oldest intraplate events of the proto-Amazonian craton. Trace elements and isotopic values suggest that the dyke parent melt for those dykes have a crustal component derived from a sedimentary source similar to GLOSS (GLObal Subducting Sediment compositions). This is consistent with the emplacement of the dykes in a supra-subduction setting or in a post-collisional setting. Trace and isotopic values of the 535?Ma dyke swarm are consistent with an enriched mantle source from EMII component. These geochemical features suggest an enrichment of the mantle from an oceanic lithosphere poor in sediments, different to that of the 1882?Ma source. The age of this swarm matches magmatic activity during a post-collisional extensive-transtensive event recorded in the marginal Araguaia belt after the amalgamation of the Amazonian Craton to the Western Gondwana during Neoproterozoic. The 200?Ma dyke swarm which is related to the CAMP (Central Atlantic Magmatic Province) and opening of the Atlantic Ocean shows trace element composition similar to Atlantic E-MORB. The coupled isotopic values are consistent with an enriched mantle source with EMII component. These particular geochemical features suggest that the plume activity responsible for the CAMP near the rifting zone has not affected the mantle beneath the Carajás region.
DS201908-1787
2019
Mazzucchelli, M.Liu, S., Tommasi, A., Vauchez, A., Mazzucchelli, M.Crust mantle coupling during continental convergence and break-up: constraints from peridotite xenoliths from the Bororema province, northeast Brazil.Tectonophysics, Vol. 766, pp. 249-269.South America, Brazilgeophysics - seismic

Abstract: We studied a suite of mantle xenoliths carried by Cenozoic volcanism in the Borborema Province, NE Brazil. These xenoliths sample a subcontinental lithospheric mantle affected by multiple continental convergence and rifting events since the Archean. Equilibrium temperatures indicate a rather hot geotherm, implying a ca. 80?km thick lithosphere. Most xenoliths have coarse-granular and coarse-porphyroclastic microstructures, recording variable degrees of annealing following deformation. The high annealing degree and equilibrated pyroxene shapes in coarse-granular peridotites equilibrated at ~900?°C indicate that the last deformation event that affected these peridotites is several hundreds of Ma old. Coarse-porphyroclastic peridotites equilibrated at 950-1100?°C probably record younger (Cretaceous?) deformation in the deep lithospheric mantle. In addition, a few xenoliths show fine-porphyroclastic microstructures and equilibrium temperatures ?1200?°C, which imply recent deformation, probably related to the dykes that fed the Cenozoic volcanism. Chemical and microstructural evidence for reactive percolation of melts is widespread. Variation in textural and chemical equilibrium among samples implies multiple melt percolation events well spaced in time (from Neoproterozoic or older to Cenozoic). Crystal preferred orientations of olivine and pyroxenes point to deformation controlled by dislocation creep with dominant activation of the [100](010) and [001]{0kl} slip systems in olivine and pyroxenes, respectively, for all microstructures. Comparison of xenoliths' seismic properties to SKS splitting data in the nearby RCBR station together with the equilibrated microstructures in the low-temperature xenoliths point to coupled crust-mantle deformation in the Neoproterozoic (Brasiliano) continental-scale shear zones, which is still preserved in the shallow lithospheric mantle. This implies limited reworking of the lithospheric mantle in response to extension during the opening of the Equatorial Atlantic in the Cretaceous, which in the present sampling is restricted to the base of the lithosphere.
DS201502-0038
2015
Mazzucchelli, M.L.Angel, R.J., Alvaro, M., Nestola, F., Mazzucchelli, M.L.Diamond thermoelastic properties and implications for determining the pressure of formation of diamond inclusion systems.Russian Geology and Geophysics, Vol. 56, 1-2, pp. 211-220.TechnologyDiamond inclusions

Abstract: The formation conditions of diamond can be determined from the residual pressure of inclusions trapped within the diamond, as measured at ambient conditions, and the equations of state (EoS) of the mineral inclusion and the host diamond. The EoS parameters of the diamond and the inclusion phase are therefore critical for determining the precision and accuracy of the calculation of formation conditions of diamonds. The questions we address are (i) How precise are these calculations? and, in particular, (ii) Do we know the EoS parameters of diamond to a precision and accuracy which do not contribute significantly to uncertainties in the geological conclusions drawn from these calculations? We present a review of the most recent compressional data, simulations, and direct elastic measurements of diamond and show them to be consistent with a room-temperature bulk modulus of K0T = 444(2) GPa and a pressure derivative K = 4.0. In combination with a thermal-pressure model with parameters aV300,0 = 2.672(3) x 10- 6 K- 1 and a single Einstein temperature 0E = 1500 K, the volume variation of diamond from room conditions to pressures and temperatures exceeding those in the Earth’s transition zone is described to within the levels of uncertainty inherent in both experimental and computational determinations. For the example of olivine inclusions in diamond, these uncertainties in the diamond EoS parameters lead to uncertainties in the entrapment pressures of no more than 0.001 GPa at low temperatures and 0.008 GPa at higher temperatures.
DS201507-0326
2015
Mazzucchelli, M.L.Milani, S., Nestola, F., Alvaro, M., Pasqual, D., Mazzucchelli, M.L., Domeneghetti, M.C., Geiger, C.A.Diamond -garnet geobarometry: the role of garnet compressibility and expansivity.Lithos, Vol. 227, pp. 140-147.TechnologyGeobarometry
DS201712-2672
2017
Mazzucchelli, M.L.Angel, R.J., Mazzucchelli, M.L., Alvaro, M., Nestola, F.EosFit-Pinc: a simple GUI for host inclusion elastic thermobarometry.American Mineralogist, Vol. 102, pp. 1957-1960.Technologygeobarometry

Abstract: Elastic geothermobarometry is a method of determining metamorphic conditions from the excess pressures exhibited by mineral inclusions trapped inside host minerals. An exact solution to the problem of combining non-linear Equations of State (EoS) with the elastic relaxation problem for elastically isotropic spherical host-inclusion systems without any approximations of linear elasticity is presented. The solution is encoded into a Windows GUI program EosFit-Pinc. The program performs host-inclusion calculations for spherical inclusions in elastically isotropic systems with full P-V-T EoS for both phases, with a wide variety of EoS types. The EoS values of any minerals can be loaded into the program for calculations. EosFit-Pinc calculates the isomeke of possible entrapment conditions from the pressure of an inclusion measured when the host is at any external pressure and temperature (including room conditions), and it can calculate final inclusion pressures from known entrapment conditions. It also calculates isomekes and isochors of the two phases.
DS201812-2853
2018
Mazzucchelli, M.L.Murri, M., Mazzucchelli, M.L., Campomenosi, N., Korsakov, A.V., Prencipe, M., Mihailova, B.D., Scambelluri, M., Angel, R.J., Alvaro, M.Raman elastic geobarometry for anisotropic mineral inclusions. MirAmerican Mineralogist, Vol. 103, pp. 1869-1872.Russiamineral inclusions

Abstract: Elastic geobarometry for host-inclusion systems can provide new constraints to assess the pressure and temperature conditions attained during metamorphism. Current experimental approaches and theory are developed only for crystals immersed in a hydrostatic stress field, whereas inclusions experience deviatoric stress. We have developed a method to determine the strains in quartz inclusions from Raman spectroscopy using the concept of the phonon-mode Grüneisen tensor. We used ab initio Hartree-Fock/Density Functional Theory to calculate the wavenumbers of the Raman-active modes as a function of different strain conditions. Least-squares fits of the phonon-wavenumber shifts against strains have been used to obtain the components of the mode Grüneisen tensor of quartz (??m1 and ?m3?) that can be used to calculate the strains in inclusions directly from the measured Raman shifts. The concept is demonstrated with the example of a natural quartz inclusion in eclogitic garnet from Mir kimberlite and has been validated against direct X-ray diffraction measurement of the strains in the same inclusion.
DS201904-0714
2019
Mazzucchelli, M.L.Anzolini, C., Nestola, F., Mazzucchelli, M.L., Alvaro, M., Nimis, P., Gianese, A., Morganti, S., Marone, F., Campione, M., Hutchison, M.T., Harris, J.W.Depth of diamond formation obtained from single periclase inclusions. SDD ( Super Deep Diamonds)Geology , Vol. 47, 3, pp. 219-222.South America, Brazil, Guyanadiamond genesis

Abstract: Super-deep diamonds (SDDs) are those that form at depths between ?300 and ?1000 km in Earth’s mantle. They compose only 1% of the entire diamond population but play a pivotal role in geology, as they represent the deepest direct samples from the interior of our planet. Ferropericlase, (Mg,Fe)O, is the most abundant mineral found as inclusions in SDDs and, when associated with low-Ni enstatite, which is interpreted as retrogressed bridgmanite, is considered proof of a lower-mantle origin. As this mineral association in diamond is very rare, the depth of formation of most ferropericlase inclusions remains uncertain. Here we report geobarometric estimates based on both elasticity and elastoplasticity theories for two ferropericlase inclusions, not associated with enstatite, from a single Brazilian diamond. We obtained a minimum depth of entrapment of 15.7 (±2.5) GPa at 1830 (±45) K (?450 [±70] km depth), placing the origin of the diamond-inclusion pairs at least near the upper mantle-transition zone boundary and confirming their super-deep origin. Our analytical approach can be applied to any type of mineral inclusion in diamond and is expected to allow better insights into the depth distribution and origin of SDDs.
DS201910-2288
2019
Mazzucchelli, M.L.Nestola, F., Zaffiro, G., Mazzucchelli, M.L., Nimis, P., Andreozzi, G.B., Periotto, B., Princivalle, F., Lenaz, D., Secco, L., Pasqualetto, L., Logvinova, A.M., Sobolev, N.V., Lorenzetti, A., Harris, J.W.Diamond inclusion system recording old deep lithosphere conditions at Udachnaya ( Siberia).Nature Research, Vol. 9, 12586 8p. PdfRussia, Siberiadeposit - Udachnaya

Abstract: Diamonds and their inclusions are unique fragments of deep Earth, which provide rare samples from inaccessible portions of our planet. Inclusion-free diamonds cannot provide information on depth of formation, which could be crucial to understand how the carbon cycle operated in the past. Inclusions in diamonds, which remain uncorrupted over geological times, may instead provide direct records of deep Earth’s evolution. Here, we applied elastic geothermobarometry to a diamond-magnesiochromite (mchr) host-inclusion pair from the Udachnaya kimberlite (Siberia, Russia), one of the most important sources of natural diamonds. By combining X-ray diffraction and Fourier-transform infrared spectroscopy data with a new elastic model, we obtained entrapment conditions, Ptrap?=?6.5(2) GPa and Ttrap?=?1125(32)-1140(33) °C, for the mchr inclusion. These conditions fall on a ca. 35?mW/m2 geotherm and are colder than the great majority of mantle xenoliths from similar depth in the same kimberlite. Our results indicate that cold cratonic conditions persisted for billions of years to at least 200?km in the local lithosphere. The composition of the mchr also indicates that at this depth the lithosphere was, at least locally, ultra-depleted at the time of diamond formation, as opposed to the melt-metasomatized, enriched composition of most xenoliths.
DS201912-2768
2019
Mazzucchelli, M.L.Alvaro, M., Mazzucchelli, M.L., Angel, R.J., Murri, M., Campmenosi, N., Scambelluri, M., Nestola, F., Korsakov, A., Tomilenko, A.A., Marone, F., Morana, M.Fossil subduction recorded by quartz from the coesite stability field. GeobarometryGeology, in press, 5p. PdfRussia, Yakutiadeposit - Mir

Abstract: Metamorphic rocks are the records of plate tectonic processes whose reconstruction relies on correct estimates of the pressures and temperatures (P-T) experienced by these rocks through time. Unlike chemical geothermobarometry, elastic geobarometry does not rely on chemical equilibrium between minerals, so it has the potential to provide information on overstepping of reaction boundaries and to identify other examples of non-equilibrium behavior in rocks. Here we introduce a method that exploits the anisotropy in elastic properties of minerals to determine the unique P and T of entrapment from a single inclusion in a mineral host. We apply it to preserved quartz inclusions in garnet from eclogite xenoliths hosted in Yakutian kimberlites (Russia). Our results demonstrate that quartz trapped in garnet can be preserved when the rock reaches the stability field of coesite (the high-pressure and high-temperature polymorph of quartz) at 3 GPa and 850 °C. This supports a metamorphic origin for these xenoliths and sheds light on the mechanisms of craton accretion from a subducted crustal protolith. Furthermore, we show that interpreting P and T conditions reached by a rock from the simple phase identification of key inclusion minerals can be misleading.
DS201912-2804
2019
Mazzucchelli, M.L.Mazzucchelli, M.L., Reali, A., Morganti, S., Angel, R.J., Alvaro, M.Elastic geobarometry for anistropic inclusions in cubic hosts. ( not specific to diamonds)Lithos, Vol. 350-351, 105218 11p. PdfMantlegeobarometry

Abstract: Mineral inclusions entrapped in other minerals may record the local stresses at the moment of their entrapment in the deep Earth. When rocks are exhumed to the surface of the Earth, residual stresses and strains may still be preserved in the inclusion. If measured and interpreted correctly through elastic geobarometry, they give us invaluable information on the pressures (P) and temperatures (T) of metamorphism. Current estimates of P and T of entrapment rely on simplified models that assumes that the inclusion is spherical and embedded in an infinite host, and that their elastic properties are isotropic. We report a new method for elastic geobarometry for anisotropic inclusions in quasi-isotropic hosts. The change of strain in the inclusion is modelled with the axial equations of state of the host and the inclusion. Their elastic interaction is accounted for by introducing a 4th rank tensor, the relaxation tensor, that can be evaluated numerically for any symmetry of the host and the inclusion and for any geometry of the system. This approach can be used to predict the residual strain/stress state developed in an inclusion after exhumation from known entrapment conditions, or to estimate the entrapment conditions from the residual strain measured in real inclusions. In general, anisotropic strain and stress states are developed in non-cubic mineral inclusions such as quartz and zircon, with deviatoric stresses typically limited to few kbars. For garnet hosts, the effect of the mutual crystallographic orientation between the host and the inclusion on the residual strain and stress is negligible when the inclusion is spherical and isolated. Assuming external hydrostatic conditions, our results suggest that the isotropic and the new anisotropic models give estimations of entrapment conditions within 2%.
DS1989-0264
1989
Mazzucchelli, R.H.Chork, C.Y., Mazzucchelli, R.H.Spatial filtering of exploration geochemical dat a using EDA and robuststatisticsJournal of Geochemical Exploration, Vol. 34, No. 3, November pp. 221-243BrazilSan Francisco Basin, Zinc geochemistry
DS2002-1012
2002
Mazzuoli, R.Matteini, M., Mazzuoli, R., Omarini, R., Cas, R., MaasThe geochemical variations of the upper Cenozoic volcanism along Calama Olacapato El Toro transversalTectonophysics, Vol.345,1-4,Feb.15, pp. 211-27.AndesGeodynamics - tectonics, fault system, Petrogenetic
DS202110-1613
2021
Mazzurchelli, M.Faccincani, L., Faccini, B., Casetta, F., Mazzurchelli, M., Nastola, F., Coltorti, M.EoS of mantle minerals coupled with composition and thermal state of the lithosphere: inferring the density structure of peridotitic systems.Lithos, Vol. 401-404, 12p. PdfMantle peridotites

Abstract: Unravelling the physical state and properties of mantle rocks is crucial for understanding both plate tectonics, seismic activity, and volcanism. In this context, the knowledge of accurate elastic parameters of constituent mineral phases, and their variations with pressure (P) and temperature (T), is an essential requirement, that coupled with the thermal state of the lithosphere can provide a better understanding of its petrophysics and thermochemical structure. In this paper, we present an assessment of the thermoelastic parameters [in the form of P-V-T-K Equations of State (EoS)] of orthopyroxene, clinopyroxene, spinel and garnet based on X-Ray diffraction data and direct elastic measurements available in literature. The newly developed EoS are appropriate to describe the elastic behaviour of these phases under the most relevant P-T conditions and bulk compositions of the Earth's mantle. In combination with the published EoS for mantle olivine and magnesiochromite, these EoS are suitable to calculate the physical properties of mantle peridotites and their variation with P and T. Thanks to these EoS, we can evaluate how the variations in bulk composition and thermal regimes affect the density structure of the lithospheric mantle. Accordingly, the density structure of fertile and depleted peridotitic systems was calculated along the 35, 45 and 60 mWm?2 geothermal gradients at P comprised between 1 and 8 GPa. Under very cold geothermal gradients, the density of both fertile and depleted peridotitic systems progressively increases with depth, whereas under relatively hot conditions a first downwards decrease from 1 to ca 3 GPa is observed, followed by an increase downward. In mantle sections characterized by intermediate geotherms (45 mWm?2), the behaviour of the two systems differs up to ca 4 GPa, as the density of the depleted system remains nearly constant down to this depth whereas it moderately increases in the fertile system. The results of our simplified parameterisation, in agreement with classical thermodynamic modelling, indicate that the density structure of the lithospheric mantle is predominantly controlled by the P - T gradient variations, with some compositional control mostly arising at cold-intermediate thermal conditions. Integrated by geophysical and thermodynamic modelling, the newly developed and selected EoS could provide an alternative strategy to infer the elastic properties of mineral phases and peridotite rocks, under the most relevant P-T conditions and compositions of the Earth's mantle, without requiring sets of end-member properties and solution models.
DS1994-1129
1994
Mbalu-Keswa, C.Mbalu-Keswa, C., Gold, D.P., Tedeski, J.R.Inclusions in clinopyroxene xenocrysts from the Tanoma kimberlite IndianaCounty, Pennsylvania.Geological Society of America Abstracts, Vol. 26, No. 3, March, p. 60. AbstractGlobalKimberlite inclusions, Tanoma
DS1994-1130
1994
Mbalu-Keswa, C.Mbalu-Keswa, C., Gold, D.P., Tedeski, J.R.Polymineralic blebs in pyroxene megacrysts from the Tonoma kimberlites, Indiana County, Pennsylvania, USAGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p. PosterGlobalMegacrysts, Tonoma
DS201704-0625
2016
Mbalu-Keswa, C.Gold, D., Doden, A.G., Mbalu-Keswa, C., Tedeski, J.R., Mathur, R.The Rogue kimberlite dikes in Indiana County, Pennsylvania Part 1. unusual intrusive habit of kimberlite dikes in coal seams.Guidebook 81st annual field conference of Pennsylvania Geologists, Oct. 6-8, pp. 121-160.United States, PennsylvaniaDeposit - Rogue
DS201704-0626
2016
Mbalu-Keswa, C.Gold, D., Doden, A.G., Mbalu-Keswa, C., Tedeski, J.R., Mathur, R.Supplement to guidebook: Petrography of the Tanoma and Ernest kimberlites.Guidebook 81st annual field conference of Pennsylvania Geologists, Oct. 6-8, pp. 263-268.United States, PennsylvaniaDeposit - Rogue
DS202106-0974
2021
Mbang, C.S.Tchoukeu, C.D.N., Baseka, C.A., Djomani, Y.P., Rousse, S., Etame,J., Llubes, M., Seoane,L., Mbang, C.S., Yomba, A.E.Crustal thickness, depth to the bottom of magnetic sources and thermal structure of the crust from Cameroon to Central African Republic: preliminary results for a better understanding of the origin of the Bangui Magnetic Anomaly.Journal of African Earth Sciences, Vol. 179, 104206, 21p. pdfAfrica, Cameroon, Central African Republicgeophysics

Abstract: The Bangui Magnetic Anomaly (BMA) is one of the largest magnetic anomalies in the world whose origin is still not known. This research investigated the crustal thickness, Curie depths and thermal structures in the Central African sub-regions - Cameroon, Central African Republic and adjacent countries - which are largely characterized by the Bangui Magnetic Anomaly. To achieve a better understanding and clearer idea of the location of the possible sources of the BMA, analyses of geothermal structures were conducted. Two potential methods were used: gravity to evaluate the crustal thickness and magnetics for geothermal analysis. Spectral analysis of gravity data shows that crustal thickness range between 14 and 55 km. The highest depths were found in Central African Republic. The lower values of crustal thickness were obtained in South-Chad basin with a minimum of roughly 14 km. Geothermal analysis is carried out using the Curie point depth, thermal gradient and heat-flow evaluations. The results show that the BMA is related to a thick crust of roughly 40 km. Depth to the bottom of possible sources does not exceed the lower crust. The mean Curie point depth estimated is 38 km with an error of ±2 km. Geothermal results also show the difference in the thermal behaviour between the crust in the Pan African and Precambrian domain. The mobile zone which constitutes the Pan African domain is associated with a thin crust of high heat-flow values of 65 mW/m2. However, the Precambrian domain beneath the BMA is associated with a thick crust with lower heat-flow values (roughly 45 mW/m2). The difference between crustal thickness and Curie point depths shows that all the sources of the BMA are crustal. The present results are in favour of a geological origin for the Bangui Magnetic anomaly.
DS201412-0564
2014
Mbangula, I.Mbangula, I.Namdeb's Probe Drill Platform ( PDP): exploring the notorious ultra-sha;;ow water area, Mining Area No. 1, Namibia.GSSA Kimberley Diamond Symposium and Trade Show provisional programme, Sept. 10-12, POSTERAfrica, NamibiaMining area no. 1
DS201608-1411
2015
Mbayi, L.Grynberg, R., Mbayi, L.The Global diamond industry: economics and Development. Vol. I and IIPalgrave Hamilton, Hampshire (Publishers), Two separate Vols. Each $ 75.00 Kindle editionGlobalBook - diamond industry
DS1997-0307
1997
Mbede, E.Ebinger, C., Djomani, Y.P., Mbede, E., Foster, DawsonRifting Archean lithosphere: the Eyasi Manyara Natron Rifts, East AfricaJournal of the Geological Society of London, Vol. 154, pp. 947-960.Tanzania, East AfricaTectonics, Geophysics - gravity anomalies
DS200812-0560
2008
Mbede, E.Kervyn, M., Ernst, G.G., Harris, A.J.L., Belton, F., Mbede, E., Jacobs, P.Thermal remote sensing of the low intensity carbonatite volcanism of Oldoinyo Lengai, Tanzania,International Journal of Remote Sensing, Vol. 29, 22, pp. 6467-6499.Africa, TanzaniaCarbonatite
DS1991-1084
1991
Mbede, E.I.Mbede, E.I.The sedimentary basins of Tanzania- reviewedJournal of African Earth Sciences, Vol. 13, No. 3-4, pp. 291-298TanzaniaBasins, Review
DS201012-0479
2009
Mbedi, E.Mbedi, E., Kampunzu, A.B., Armstrong, R.A.Neoproterozoic inheritance during Cainozoic rifting in the western and southwestern branches of the East African Rift system: evidence from carbonatite alkalineTanzanian Journal of Earth Science, Vol. 1, Dec. pp. 29-37.Africa, TanzaniaCarbonatite, Nachendezwaya
DS201809-2100
2018
Mbogoni, G.J.Tepp, G., Ebinger, C.J., Zal, H., Gallacher, R., Accardo, N., Shillington, D.J., Gaherty, J., Keir, D., Nyblade, A.A., Mbogoni, G.J., Chindandali, P.R.N., Ferdinand-Wambura, R., Mulibo, G.D., Kamihanda, G.Seismic anistrotropy of the Upper mantle below the western rfit, East Africa.Journal of Geophysical Research, Vol. 123, 7, pp. 5644-5660.Africa, east Africageophysics - seismic

Abstract: Although the East African rift system formed in cratonic lithosphere above a large?scale mantle upwelling, some sectors have voluminous magmatism, while others have isolated, small?volume eruptive centers. We conduct teleseismic shear wave splitting analyses on data from 5 lake?bottom seismometers and 67 land stations in the Tanganyika?Rukwa?Malawi rift zone, including the Rungwe Volcanic Province (RVP), and from 5 seismometers in the Kivu rift and Virunga Volcanic Province, to evaluate rift?perpendicular strain, rift?parallel melt intrusion, and regional flow models for seismic anisotropy patterns beneath the largely amagmatic Western rift. Observations from 684 SKS and 305 SKKS phases reveal consistent patterns. Within the Malawi rift south of the RVP, fast splitting directions are oriented northeast with average delays of ~1 s. Directions rotate to N?S and NNW north of the volcanic province within the reactivated Mesozoic Rukwa and southern Tanganyika rifts. Delay times are largest (~1.25 s) within the Virunga Volcanic Province. Our work combined with earlier studies shows that SKS?splitting is rift parallel within Western rift magmatic provinces, with a larger percentage of null measurements than in amagmatic areas. The spatial variations in direction and amount of splitting from our results and those of earlier Western rift studies suggest that mantle flow is deflected by the deeply rooted cratons. The resulting flow complexity, and likely stagnation beneath the Rungwe province, may explain the ca. 17 Myr of localized magmatism in the weakly stretched RVP, and it argues against interpretations of a uniform anisotropic layer caused by large?scale asthenospheric flow or passive rifting.
DS1993-1130
1993
mBudahn, J.R.Nielson, J.E, mBudahn, J.R., Unruh, D.M., Wilshire, H.G.Actualistic models of mantle metasomatism documented in a composite xenolith from Dish Hill, California.Geochemica et Cosmochimica Acta, Vol. 57, No. 1, January pp. 105-121.CaliforniaMantle, Dish Hill
DS1998-1565
1998
M-CWard, M-C, Lawrence, R.D.Comparable transaction analysis: the market is always rightPros. Developers Assoc, Short course pp. 53-68GlobalReserves, discoveries, success, economics, Valuation
DS2001-0687
2001
McA PowellLi, Z.X., McA PowellAn outline of the paleogeographic evolution of the Australasian region since beginning of NeproterozoicEarth Science Reviews, Vol. 53, No. 3-4, Apr. pp. 237-77.Australia, AsiaTectonics, 20 coloured illustrations
DS1995-1184
1995
Mcacandless, T.E.Mcacandless, T.E.Modeling carbon reservoirs and protoliths for eclogitic diamond: support for ancient microbial carbon source.Eos, Abstracts, Vol. 76, No. 17, Apr 25, p. S 296.MantleEclogite, Diamond
DS1960-0282
1962
Mcadam, R.C.Nickel, E.L., Mcadam, R.C.Niobian Perovskite from Oka Quebec; a New Classification For Minerals of the Perovskite Group.Canadian Mineralogist., Vol. 7, PP. 683-697.Canada, QuebecRelated Rocks
DS1994-1131
1994
MCadContourMCadContourBrief overview of ProgramUnknown, GlobalComputer, Program -MCadContour 4.0
DS1990-0470
1990
McAlister, E.O.Fink, J.B., Sternberg, B.K., McAlister, E.O., Wieduwilt, W.G.Induced polarization. Applications and case studiesSociety of Exploration Geophysicists, Vol. 4, 414pGlobalBook -table of contents, Geophysics -IP
DS1992-1016
1992
McAllister, M.L.McAllister, M.L.Changing political agendasC.r.s. Studies, Proceedings volume, 170pCanadaBook -table of contents, Economics, politics, mineral industries, labour
DS1992-1017
1992
McAllister, M.L.McAllister, M.L.Changing political agendas and the Canadian mining industryCrs Perspectives, No. 41, November pp. 23-27CanadaEconomics, Mining
DS1992-1018
1992
McAllister, M.L.McAllister, M.L.Prospects for the mineral industry: exploring public perceptions and developing political agendasCentre for Resource Studies, Working Paper No. 50, 27pCanadaEconomics, Mining industry crisis
DS1992-1019
1992
McAllister, M.L.McAllister, M.L., Schneider, T.F.Mineral policy update 1985- 1989. Policy and program changes affecting the Canadian Mineral IndustryCentre for Resource Studies, Queen's University, July 142p. approc. $ 30.00CanadaEconomics, Mineral policy
DS1994-0879
1994
McAllister, M.L.Karvinen, W.O., McAllister, M.L.Rising to the surface: emerging groundwater policy trends in CanadaCentre for Resource Studies, Mon. 29, 149p. $ 25.00CanadaGroundwater, Environment
DS1997-0746
1997
McAllister, M.L.McAllister, M.L., Alexander, C.J.A stake in the future: redefining the Canadian Mineral IndustryUbc Press, 248p. approx. $ 75.00CanadaBook - ad, Mineral industry - future, legal
DS2000-0639
2000
McAllister, M.L.McAllister, M.L., Milioli, G.Mining sustainably: opportunities for Canada and BrasilMinerals and Energy, Vol. 15, No. 2, pp. 3-14.Canada, BrazilEnvironment
DS201312-0272
2013
McAllister, M.L.Fonseca, A., Fitzpatrick, P., McAllister, M.L.Government and voluntary policy making for sustainability in mining towns: a longitudinal analysis.Natural Resources Forum, Vol. 37, 4, Nov. 1, pp. 211-220.GlobalLegislation
DS1975-0906
1979
Mcallister, R.H.Akella, J., Rao, P.S., Mcallister, R.H., Boyd, F.R., Meyer, H.O.Mineralogical Studies on the Diamondiferous Kimberlite of The Wajrakarur Area, Southern India #2Proceedings of Second International Kimberlite Conference, Vol. 1, PP. 172-177.India, Andhra PradeshMineralogy
DS1970-0759
1973
Mcandrew, J.Mcandrew, J., Marsden, .M.A.H.Geomorphology of the Western District Volcanic Plains, Lakes and Coastline.In:regional Guide To Victorian Geology, PP. 100-112.Australia, VictoriaGeomorphology, Lake Ballenmerri, Kimberlite
DS201212-0227
2012
McAndrews, J.H.Gao, C., McAndrews, J.H., Wang, X., Menzies, J., Turton, C.L., Wood, B.D., Pei, J., Kodors, C.Glaciation of North America in the James Bay Lowland, Canada, 3-5 Ma.Geology, Vol. 40, 11, pp. 975-978.Canada, Ontario, James Bay LowlandsGeomorphology
DS200412-0767
2004
McArdle, N.J.Halls, H.C., McArdle, N.J., Gratton, M.N., Hill, M.J., Shaw, J.Microwave paleointensities from dyke chilled margins: a way to obtain long term variations in geodynamo intensity for the last tPhysics of the Earth and Planetary Science Interiors, Vol. 147, 2-3, Nov. 15, pp.183-195.Canada, OntarioMattachewan dyke swarm, geochronology, Biscotasing, Mar
DS1975-0517
1977
Mcarthur, G.Godwin, C.I., Mcarthur, M., Mcarthur, G.Geology of the Mountain Diatreme: a Possible Kimberlite in The Mackenzie Fold Belt, Northwest Territories.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)/SEG/CGU ANNUAL MEETING, HELD VANCOUVER., Vol. 2, P. 21. (abstract.).Canada, Northwest TerritoriesGeology
DS1991-1085
1991
McArthur, J.M.McArthur, J.M.Strontium-isotope stratigraphy. Brief overview of definition of how they may be usedGeology Today, November-December pp. 5-i-vGlobalStratigraphy, Strontium-isotope geochronology
DS1992-1020
1992
McArthur, J.M.McArthur, J.M., Burnett, J., Hancock, J.M.Strontium isotopes at K/T boundaryNature, Vol. 355, No. 6355, January 2, p.28GlobalBoundary, Geochronology
DS1975-0517
1977
Mcarthur, M.Godwin, C.I., Mcarthur, M., Mcarthur, G.Geology of the Mountain Diatreme: a Possible Kimberlite in The Mackenzie Fold Belt, Northwest Territories.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)/SEG/CGU ANNUAL MEETING, HELD VANCOUVER., Vol. 2, P. 21. (abstract.).Canada, Northwest TerritoriesGeology
DS1980-0226
1980
Mcarthur, M.L.Mcarthur, M.L., Tipnis, R.S., Godwin, C.I.Early and Middle Ordovician Conodont Fauna from the Mountain Diatreme, Northern Mackenzie Mountains, District of Mackenzie.Geological Survey of Canada (GSC) PAPER., No. 80-1A, PP. 363-368.Canada, Northwest TerritoriesPaleontology
DS1997-0115
1997
mCassidy, J.F.Bostock, M.G, mCassidy, J.F.Upper mantle stratigraphy beneath the southern Slave CratonCanadian Journal of Earth Sciences, Vol. 34, No. 5, May pp. 577-587Northwest TerritoriesCraton, Stratigraphy
DS1982-0414
1982
Mcbain, D.R.Mcbain, D.R., Cra exploration pty. ltd.El 817- Report on the Partial Surrender of Gibralter Rocks, south Australia 18th. January 1982.South Australia Open File., No. E4474, 11P. UNPUBL.Australia, South AustraliaDiamonds, Gravels, Sampling, Assay, Geophysics, Tertiary, Mulgathi
DS1982-0415
1982
Mcbain, D.R.Mcbain, D.R., Kennedy, D.R., Finch, I.D., Cra exploration pty.El 817- Gibralter Rocks, South Australia, Progress and Final Reports from 15/6/68 to 15/6/82.South Australia Open File., No. E4257, 16P. UNPUBL.Australia, South AustraliaDiamonds, Geophysics, Ground Magnetics, Sampling, Gravels, Mulgat
DS2003-0719
2003
McBean, D.Kirkley, M., Mogg, T., McBean, D.Snap Lake field trip guide8th. International Kimberlite Conference Large Core Exhibit volume, 12p.Northwest TerritoriesGeology - field trip guide, Deposit - Snap Lake
DS2003-0895
2003
McBean, D.McBean, D., Kirkley, M., Revering, C.Structural controls on the morphology of Snap Lake kimberlite dyke8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractNorthwest TerritoriesKimberlite geology and economics, Deposit - Snap Lake
DS200412-1008
2003
McBean, D.Kirkley, M., Mogg, T., McBean, D.Snap Lake field trip guide.8th. International Kimberlite Conference Large Core Exhibit volume, 12p.Canada, Northwest TerritoriesGeology - field trip guide Deposit - Snap Lake
DS200512-0071
2005
McBean, D.Baudemont, D., McBean, D., Kirkley, M.Early Paleozoic deformation in the southern Slave Craton: evidence from the 530 m.y. Snap Lake kimberlite.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, Northwest TerritoriesGeochronology, dyke geometry
DS200712-0911
2006
McBean, D.Ross, M., McBean, D.Snap Lake diamond project geology update.34th Yellowknife Geoscience Forum, p. 50. abstractCanada, Northwest TerritoriesSnap Lake - geology
DS201607-1286
2016
McBeath, A.Bird, M.I., Wynn, J.G., Saiz, G., Wurster, C.W., McBeath, A.The pyrogenic carbon cycle.Annual Review of Earth and Planetary Sciences, Vol. 43, pp. 273-298.MantleCarbon

Abstract: Pyrogenic carbon (PyC; includes soot, char, black carbon, and biochar) is produced by the incomplete combustion of organic matter accompanying biomass burning and fossil fuel consumption. PyC is pervasive in the environment, distributed throughout the atmosphere as well as soils, sediments, and water in both the marine and terrestrial environment. The physicochemical characteristics of PyC are complex and highly variable, dependent on the organic precursor and the conditions of formation. A component of PyC is highly recalcitrant and persists in the environment for millennia. However, it is now clear that a significant proportion of PyC undergoes transformation, translocation, and remineralization by a range of biotic and abiotic processes on comparatively short timescales. Here we synthesize current knowledge of the production, stocks, and fluxes of PyC as well as the physical and chemical processes through which it interacts as a dynamic component of the global carbon cycle.
DS1950-0491
1959
Mcbirney, A.R.Mcbirney, A.R.Factors Governing the Emplacement of Volcanic NecksAmerican Journal of Science, Vol. 257, PP. 431-448.GlobalBreccia
DS1995-1185
1995
McBirney, A.R.McBirney, A.R.Mechanisms of differentiation in the Skaergaard intrusionJournal of the Geological Society of London, Vol. 152, pt. 3, May pp. 421-436GlobalLayered intrusion, Skaergaard
DS1995-1186
1995
McBirney, A.R.McBirney, A.R., Hunter, R.H.The cumulate paradigm reconsideredJournal of Geology, Vol. 103, No. 1, Jan. pp. 114-122GlobalCumulate texture, Layered intrusions
DS1997-0117
1997
McBirney, A.R.Boudreau, A.E., McBirney, A.R.The Skaergaard layered series: part III non-dynamic layeringJournal of Petrology, Vol. 38, No. 8, Aug. 1, pp. 1003-1020GreenlandLayered intrusion, Deposit - Skaergaard
DS1998-0969
1998
McBirney, A.R.McBirney, A.R.The Skaergaard layered series Platinum, Vanadium Included trace elementsJournal of Petrology, Vol. 39, No. 2, Feb. 1, pp. 255-276NorwayLayered intrusion, Geochemistry
DS1998-1383
1998
McBirney, A.R.Sonnenthal, E.L., McBirney, A.R.The Skaergaard layered series. Pt. IV. Reaction-transport simulations of foundered blocksJournal of Petrology, Vol. 39, No. 4, Apr. pp. 633-661GreenlandCrystallization, Melt composition, convection
DS1991-1189
1991
McBratney, A.B.Moran, C.J., McBratney, A.B.STRUCTURA: a C program for estimating attributes of two=phase heterogeneous structures digitized from planar specimensComputers and Geosciences, Vol. 17, No. 3, pp. 335-350GlobalProgram -STRUCTURA.
DS1960-0337
1963
Mcbride, B.Edwards, C.B., Dribble, C.D., Mcbride, B., Roger, T.H.Prospecting for Diamonds in Tanganyika 1959-1961United Nations Report, UNPUBL.Tanzania, East AfricaGeology
DS1985-0732
1985
Mcbride, J.Wille, D.M., Brown, L.D., Nelson, D.K., Arnow, J.A., Mcbride, J.The Surrency Bright Spot: Possible Evidence for Fluid in The Deep Crust.Geological Society of America (GSA), Vol. 17, No. 7, P. 751. (abstract.).United States, Appalachia, GeorgiaMidcontinent, Geotectonics, Suture Zone, Rift
DS1995-1187
1995
McBride, J.McBride, J.Rhenium- Osmium (Re-Os) isotopic constraints on the origin and evolution of the Australian continental lithosphere.Eos, Abstracts, Vol. 76, No. 17, Apr 25, p. S 294.AustraliaTectonics, Lithosphere
DS200912-0507
2009
McBride, J.Mitchell, R.H., Kjarsgaard, B.A., McBride, J.Mineralogy of juvenile lapilli in Fort a la Corne pyroclastic kimberlites.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyCanada, SaskatchewanMagma volatiles
DS201112-0655
2009
McBride, J.McBride, J.The petrography and mineralogy of the C29/30 Candle Lake kimberlite, Saskatchewan, Canada.Thesis: Msc. Lakehead University, Canada, SaskatchewanThesis - note availability based on request to author
DS202109-1469
2021
McBride, J.Good, D.J., Hollings, P., Dunning, G., Epstein, R., McBride, J., Jedemann, A., Magnus, S., Bohav, T., Shore, G.A new model for the Coldwell Complex and associated dykes of the Midcontinent Rift, Canada.Journal of Petrology, Vol. 62, 7, 10.1093/petrology/ega036Canadadeposit - Coldwell

Abstract: Mafic intrusions on the NE shoulder of the Midcontinent Rift (Keweenawan LIP), including Cu-PGE mineralized gabbros within the Coldwell Complex (CC), and rift parallel or radial dykes outside the CC are correlated based on characteristic trace element patterns. In the Coldwell Complex, mafic rocks are subdivided into four groups: (1) early metabasalt; (2) Marathon Series; (3) Layered Series; (4) Geordie-Wolfcamp Series. The Marathon Series are correlated with the rift radial Abitibi dykes (1140?Ma), and the Geordie-Wolfcamp Series with the rift parallel Pukaskwa and Copper Island dykes. U-Pb ages determined for five gabbros from the Layered and Marathon Series are between 1107•7 and 1106•0?Ma. Radiogenic isotope ratios show near chondritic (CHUR) ?Nd(1106?Ma) and 87Sr/86Sri values that range from -0•38 to +1•13 and 0•702537 to 0•703944, respectively. Distinctive geochemical properties of the Marathon Series and Abitibi dykes, such as Ba/La (14-37), Th/Nb (0•06-0•12), La/Sm (3•8-7•7), Sr/Nd (21-96) and Zr/Sm (9-19), are very different from those of the Geordie-Wolfcamp Series and a subset of Copper Island and Pukaskwa dykes with Ba/La (8•7-11), Th/Nb (0•12-0•13), La/Sm (6•7-7•9), Sr/Nd (5-7•8) and Zr/Sm (18-24). Each unit exhibits covariation between incompatible element ratios such as Zr/Sm and Nb/La or Gd/Yb, Sr/Nd and Ba/La, and Nb/Y and Zr/Y, which are consistent with mixing relationship between two or more mantle domains. These characteristics are unlike those of intrusions on the NW shoulder of the MCR, but resemble those of mafic rocks occurring in the East Kenya Rift. The results imply that an unusual and long-lived mantle source was present in the NE MCR for at least 34?Myr (spanning the 1140?Ma Abitibi dykes and the 1106?Ma Marathon series) and indicate potential for Cu-PGE mineralization in an area much larger than was previously recognized.
DS1982-0416
1982
Mcbride, J.H.Mcbride, J.H., Downs, J.W.Structural Significance of Circular Land sat Anomalies in The Ozark Region of Missouri and Arkansaw.Geological Society of America (GSA), Vol. 14, No. 7, PP. 559-560, (abstract.).GlobalMid-continent
DS1985-0487
1985
Mcbride, J.H.Nelson, K.D., Arnow, J.A., Mcbride, J.H., Wille, D.M., Brown, L.New Cocorp Profiling in the Southeastern U.s.: Major Features and Regional Implications.Geological Society of America (GSA), Vol. 17, No. 7, P. 675. (abstract.).United States, Appalachia, GeorgiaMidcontinent
DS1988-0449
1988
McBride, J.H.McBride, J.H., Nelson, K.D.Integration of COCORP deep reflection and magnetic anomaly analysis in the southeastern United States: implications for origin of the Brunswick and EastCoasGeological Society of America (GSA) Bulletin, Vol. 100, No. 3, March pp. 436-445GlobalBlank
DS1991-1086
1991
McBride, J.H.McBride, J.H.Constraints on the structure and tectonic development of the early Mesozoic south Georgia Rift, southeastern United States; seismic reflection data processing &intTectonics, Vol. 10, No. 5, October pp. 1065-1083GeorgiaTectonics, Geophysics -seismics
DS1995-1188
1995
McBride, J.H.McBride, J.H.Does the Great Glen Fault really disrupt MOHO and upper mantle structure?Tectonics, Vol. 14, No. 2, Apr. pp. 422-34.GlobalTectonics - discontinuity, Geophysics - seismics
DS1997-0747
1997
McBride, J.H.McBride, J.H.Variable deep structure of a midcontinent fault and fold zone from seismicreflection: la Salle deformationGeological Society of America (GSA) Bulletin., Vol. 108, No. 11, Nov. pp. 1502-13.GlobalBasin, tectonics, Geophysics - seismic
DS1998-1409
1998
McBride, J.H.Stern, T.A., McBride, J.H.Seismic exploration of continental strike slip zonesTectonophysics, Vol. 286, No. 1-4, Mar. 10, pp. 63-78.MantleGeophysics - seismic
DS1999-0449
1999
McBride, J.H.McBride, J.H., England, R.W.Window into the Caledonian orogen: structure of the crust beneath East Shetland platform, U.K.Geological Society of America (GSA) Bulletin., Vol. 111, No. 7, July pp. 1030-41.GlobalOrogeny - structure
DS1999-0450
1999
McBride, J.H.McBride, J.H., Kolata, D.R.Upper crust beneath the central Illinois basin, United StatesGeological Society of America (GSA) Bulletin., Vol. 111, No. 3, Mar. pp. 375-94.GlobalGeophysics - seismics, New Madrid seismic zone, Precambrian basement
DS2003-0105
2003
McBride, J.H.Bexfield, C.E., McBride, J.H., Pugen, A.J.M., Nelson, W.J.Mesozoic Cenozoic deformation near the northern tip of the Madrid seismic zoneGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.15.IllinoisGeophysics - seismics, lithosphere
DS2003-0896
2003
McBride, J.H.McBride, J.H., Kolata, D.R., Hildenbrand, T.G.Geophysical constraints on understanding the origin of the Illinois Basin and itsTectonophysics, Vol. 363, 1-2, Feb. 20, pp. 45-78.IllinoisGeophysics - seismics, Tectonics
DS2003-0897
2003
McBride, J.H.McBride, J.H., Kolata, D.R., Hildenbrand, T.G.Geophysical constraints on understanding the origin of the Illinois basin and itsTectonophysics, Vol. 363, No. 1-2, Feb. 20, pp. 45-78.Illinois, IndianaGeophysics - seismics, New Madrift Rift system, Reelfoot Rift, Rough Creek Gra
DS200412-0144
2003
McBride, J.H.Bexfield, C.E., McBride, J.H., Pugen, A.J.M., Nelson, W.J.Mesozoic Cenozoic deformation near the northern tip of the Madrid seismic zone.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.15.United States, IllinoisGeophysics - seismics, lithosphere
DS200412-1254
2003
McBride, J.H.McBride, J.H., Kolata, D.R., Hildenbrand, T.G.Geophysical constraints on understanding the origin of the Illinois Basin and its underlying crust.Tectonophysics, Vol. 363, 1-2, Feb. 20, pp. 45-78.United States, IllinoisGeophysics - seismics Tectonics
DS200412-1255
2004
McBride, J.H.McBride, J.H., White, R.S., Smallwood, J.R., England, R.W.Must magmatic intrusion in the lower crust produce reflectivity.Tectonophysics, Vol. 388, 1-4, Sept. 13, pp. 271-297.Europe, IcelandMantle plume, volcanism, geophysics - seismics
DS1996-0910
1996
McBride, J.S.McBride, J.S.Multi-stage evolution of Australian subcontinental mantle:Rhenium- Osmium (Re-Os) isotopic constraints from Victorian mantleGeological Society of Australia 13th. Convention held Feb., No. 41, abstracts p.279.AustraliaMantle, Geochronology
DS1996-0911
1996
McBride, J.S.McBride, J.S., Lambert, D.D., Greig, A., Nicholls, I.A.Multistage evolution of Australian subcontinental mantle: Rhenium- Osmium (Re-Os) isotopic constraints from Victorian...Geology, Vol. 24, No. 7, July pp. 631-634.Australia, VictoriaMantle xenoliths, Geochronology
DS2001-0743
2001
McBride, J.S.McBride, J.S., Lambert, D.D., Nicholls, I.A., Price, R.Osmium isotopic evidence for crust mantle interaction in the genesis of continental intraplate basalts ...Journal of Petrology, Vol. 42, No. 6, pp. 1197-1218.Australia, southeastNewer Volcanic Province, Geochronology
DS1989-0966
1989
McCabe, C.McCabe, C., Elmore, R.D.The occurrence and origin of late Paleozoic remagnization in the sedimentary rocks of North AmericaReview of Geophysics, Vol. 27, No. 4, November pp. 471-494AppalachiaGeophysics, Remagnitization -sedimentary rocks
DS1989-0967
1989
McCabe, C.McCabe, C., Jackson, M., Suffer, B.Regional patterns of magnetite authigenesis in the Appalachian basin:implications for the mechanism of late Paleozoic remagnetizationJournal of Geophys. Research, Vol. 94, No. B8, August 10, pp. 10, 429-10, 443AppalachiaGeophysics, Paleomagnetism
DS1992-1021
1992
McCabe, C.McCabe, C.The continents 500 million years agoEos Transactions, Vol. 73, No. 2, Jan. 14, p. 22. (1/2 pg.)MantleCrust, Pangea
DS1993-0937
1993
McCabe, R.Lumadyo, E., McCabe, R., Harder, S., Lee, T.Borneo: a stable portion of the Eurasian margin since the EoceneJournal of Southeast Asian Earth Sciences, Vol. 8, No. 104, pp. 225-231.GlobalPaleomagnetics, Structure
DS1988-0001
1988
McCafferty, A.E.Adkins-Heljeson, D.M., Berendsen, P., McCafferty, A.E.Correlation of aeromagnetic and gravity dat a in the Joplin 2degree quadrangle of Kansas and Missouri to basement composition and structureGeological Society of America Abstracts with Program, Vol. 20, No. 2, January p. 89. Sth. Central, LawrenceGlobalMid continent, Tectonics
DS1989-0292
1989
McCafferty, A.E.Cordell, L., McCafferty, A.E.Geophysical studies in central Midcontinent CUSMAP QuadranglesUnited States Geological Survey (USGS) Open file, United States Geological Survey (USGS)-Missouri G.S. Symp: Mineral resource potential of, p. 5. (abstract.)GlobalMidcontinent, Tectonics
DS1990-0997
1990
McCafferty, A.E.McCafferty, A.E., Adkins-Heljeson, D.M., Yarger, H.L.Complete bouguer gravity anomaly map of the Joplin Quadrangle Kansas andMissouriUnited States Geological Survey (USGS) Open File No. 89-0283, 1 sheet 1: 250, 000 $3.25, GlobalGeophysics-gravity
DS1992-1022
1992
McCafferty, A.E.McCafferty, A.E., Cordell, L.E.Geophysically inferred structural and lithologic map of the Precambrian basement in the Joplin Quandrangle, Kansas and Missouri.United States Geological Survey (USGS) Map, No. MF 2125-D.GlobalGeophysics, Structure
DS1994-0410
1994
MCCafferty, A.E.De Miranda, F.P., MCCafferty, A.E., Taranik, J.V.Reconnaissance geologic mapping of portion of rain forest covered Guianashield, using SIR-B, digital dataGeophysics, Vol. 59, No. 5, May pp. 733-742BrazilGeophysics -aeromagnetics, SIR-B.
DS2002-0501
2002
McCaffrey, K.J.W.Garde, A.A., Hamilton, M.A., Chadwick, B., Grocott, J., McCaffrey, K.J.W.The Ketilidian orogen of South Greenland: geochronology, tectonics, magmatism andCanadian Journal of Earth Science, Vol.39,5, May, pp.765-93.GreenlandTectonics
DS200412-0729
2004
McCaffrey, K.J.W.Grocott, J., McCaffrey, K.J.W., Taylor, G., Tikoff, B.Vertical coupling and decoupling in the lithosphere.Geological Society of London Special Paper, No. 227, 352p. $140.MantleBook - lithosphere
DS200512-0371
2004
McCaffrey, K.J.W.Grocott, J., McCaffrey, K.J.W., Taylor, G., Tikoff, B.Vertical coupling and decoupling of the lithosphere.Geological Society of London , Special Publication 227, 352p. $134.Book - mantle, orogeny, subduction
DS201702-0232
2016
McCaffrey, K.J.W.Plethean, J.J.J., Kalnins, L.M., van Hunen, J., Biffi, P.G., Davies, R.J., McCaffrey, K.J.W.Madagascar's escape from Africa: a resolution plate reconstruction for the Western Somali Basin and for supercontinent dispersal.Geochemistry, Geophysics, Geosystems: G3, Vol. 17, 2, pp. 5036-5055.Africa, MadagascarTectonics

Abstract: Accurate reconstructions of the dispersal of supercontinent blocks are essential for testing continental breakup models. Here, we provide a new plate tectonic reconstruction of the opening of the Western Somali Basin during the breakup of East and West Gondwana. The model is constrained by a new comprehensive set of spreading lineaments, detected in this heavily sedimented basin using a novel technique based on directional derivatives of free-air gravity anomalies. Vertical gravity gradient and free-air gravity anomaly maps also enable the detection of extinct mid-ocean ridge segments, which can be directly compared to several previous ocean magnetic anomaly interpretations of the Western Somali Basin. The best matching interpretations have basin symmetry around the M0 anomaly; these are then used to temporally constrain our plate tectonic reconstruction. The reconstruction supports a tight fit for Gondwana fragments prior to breakup, and predicts that the continent-ocean transform margin lies along the Rovuma Basin, not along the Davie Fracture Zone (DFZ) as commonly thought. According to our reconstruction, the DFZ represents a major ocean-ocean fracture zone formed by the coalescence of several smaller fracture zones during evolving plate motions as Madagascar drifted southwards, and offshore Tanzania is an obliquely rifted, rather than transform, margin. New seismic reflection evidence for oceanic crust inboard of the DFZ strongly supports these conclusions. Our results provide important new constraints on the still enigmatic driving mechanism of continental rifting, the nature of the lithosphere in the Western Somali Basin, and its resource potential.
DS201911-2574
2019
McCaffrey, K.J.W.Wilson, R.W., Huseman, G.A., Buiter, S.J.H., McCaffrey, K.J.W., Dore, A.G.Fifty years of the Wilson Cycle concept in plate tectonics: an overview.IN: Cycle Concepts in Plate Tectonics, editors Wilson and Houseman , Geological Society of London special publication 470, pp. 1-17. pdfMantleplate tectonics

Abstract: It is now more than 50 years since Tuzo Wilson published his paper asking ‘Did the Atlantic close and then re-open?’. This led to the ‘Wilson Cycle’ concept in which the repeated opening and closing of ocean basins along old orogenic belts is a key process in the assembly and breakup of supercontinents. This implied that the processes of rifting and mountain building somehow pre-conditioned and weakened the lithosphere in these regions, making them susceptible to strain localization during future deformation episodes. Here we provide a retrospective look at the development of the concept, how it has evolved over the past five decades, current thinking and future focus areas. The Wilson Cycle has proved enormously important to the theory and practice of geology and underlies much of what we know about the geological evolution of the Earth and its lithosphere. The concept will no doubt continue to be developed as we gain more understanding of the physical processes that control mantle convection and plate tectonics, and as more data become available from currently less accessible regions.
DS1992-1023
1992
McCaffrey, R.McCaffrey, R.Oblique plate convergence, slip vectors, and forearc deformationJournal of Geophysical Research, Vol. 97, No. B6, June 10, pp. 8905-8916GlobalSubduction, Plate tectonics
DS200512-0698
2005
McCaffrey, R.McCaffrey, R.Block kinematics of the Pacific North America plate boundary in the southwestern United States from inversion GPS, seismological and geologic data.Journal of Geophysical Research, Vol. 110, B7, B07401 10.1029/2004 JB003307United StatesTectonics
DS201112-0656
2011
McCahon, J.McCahon, J.The final frontier - Arctic region.... mentions Gahcho Kue and general arctic conditions.Optima, April pp. 20-25.Global, ArcticExploration
DS1989-0968
1989
McCaig, A.M.McCaig, A.M.Fluid flow through fault zonesNature, Vol. 340, No. 6235, August 24, p. 600GlobalTectonics, Structure-fault
DS1991-1087
1991
McCall, G.McCall, G., Laming, D., Scott, S.GeohazradsChapman and Hall, 236p. approx. $ 40.00 United StatesGlobalBook -ad, Geohazards
DS1996-0038
1996
McCall, G.J.H.Appleton, J.D., Fuge, R., McCall, G.J.H.Environmental geochemistry and healthGeological Society of London, No. 113, 270pAfricaEnvironment, geochemistry, health, Table of contents
DS1996-0039
1996
McCall, G.J.H.Appleton, J.D., McCall, G.J.H.Environmental geochemistry and health with special reference to developingcountriesGeological Society of London, No. 113, 272p. approx. $ 98.00 United StatesGlobalGeochemistry and health, Book -ad
DS2001-0744
2001
McCall, G.J.H.McCall, G.J.H.Tektites in the geological Record. ... showers of glass from the skyGeological Society of London, 260p.GlobalTektites
DS200912-0485
2009
McCall, G.J.H.McCall, G.J.H.The carbonado diamond conundrum.Earth Science Reviews, Vol. 93, 3-4, pp. 85-91.South America, Brazil, Africa, Central African Republic, Russia, Siberia, YakutiaHistory, diamond genesis
DS200912-0486
2009
McCall, G.J.H.McCall, G.J.H.Half a century of progress in research on terrestrial impact structure: a review.Earth Science Reviews, Vol. 92, 3-4, Feb. pp. 99-172.TechnologyImpact structures - review
DS201112-0657
2011
McCall, G.J.H.McCall, G.J.H.New paradigm for the Early Earth: did plate tectonics as we know it not operate until the end of the Archean?Australian Journal of Earth Sciences, Vol. 57, 3, pp. 349-355.MantleTectonics
DS1990-0998
1990
McCall, G.W.McCall, G.W., Nabelek, P.I., Bauer, R.L., Glascock, M.D.Petrogenesis of Archean lamprophyres in the southern Vermilion graniticcomplex, northeastern Minnesota, with implications for the nature of their mantle sourceContributions to Mineralogy and Petrology, Vol. 104, No. 4, pp. 439-452MinnesotaGranite -Vermilion complex, Lamprophyres
DS1995-1189
1995
McCall, J.McCall, J.The early history of the earthGeoscientist, Vol. 6, No. 1, pp. 10-14GlobalArchean, Layman's overview
DS1995-1190
1995
McCall, J.McCall, J.The early history of the earth.... brief layman's overviewGeoscientist, Vol. 6, No. 1, pp. 10-14.GlobalHistory -brief
DS1900-0031
1900
Mccallie, S.W.Mccallie, S.W.A Preliminary Report on Mineral Resources of GeorgiaGeorgia Geological Survey Bulletin., No. 23, 164P.GlobalKimberley, Appalachia
DS1920-0290
1926
Mccallie, S.W.Mccallie, S.W.Diamonds; Mineral Resources of Georgia, 1926In: Mineral Resources of Georgia, Veatch, O., Georgia Geol., No. 23, 208P.Appalachia, GeorgiaDiamond Occurrence
DS1970-0760
1973
Mccallister, R.H.Mccallister, R.H., Meyer, H.O.A., Brookins, D.G.Pyroxene - Ilmenite Xenoliths from the Stockdale Pipe; KanProceedings of First International Kimberlite Conference, PP. 213-215, (abstract.).KansasKimberlite, Central States, Oxide-silicate Intergrowths
DS1975-0130
1975
Mccallister, R.H.Mccallister, R.H., Meyer, H.O.A., Brookins, D.G.Pyroxene - Ilmenite Xenoliths from the Stockdale Pipe; KanPhysics And Chemistry of Earth, Vol. 9, PP. 287-294.KansasKimberlite, Central States, Oxide-pyroxene Intergrowths
DS1975-0214
1975
Mccallister, R.H.Wyatt, B., Mccallister, R.H., Boyd, F.R., Ohashi, Y.An Experimentally Produced Clinopyroxene Ilmenite IntergrowtCarnegie Institute Yearbook, FOR 1974, PP. 536-542.South AfricaNodules, Petrography
DS1975-0441
1977
Mccallister, R.H.Akella, J., Mccallister, R.H., Meyer, H.O.A.Mineralogical Studies on the Diamondiferous Kimberlite of The Wajrakarur Area Southern India #1University of California LAWRENCE LIVERMORE LAB., National Technical Information Service Report No. 7807, 21P.India, Andhra PradeshMineralogy
DS1975-1130
1979
Mccallister, R.H.Mccallister, R.H.The Relationship between Unmixing in Subcaclic Diopsides And the Intrusion Rate and P T Path of Kimberlites.Kimberlite Symposium Ii, South AfricaPetrology
DS1981-0289
1981
Mccallister, R.H.Mccallister, R.H., Gordon, L.N.Subcalcic Diopsides from Kimberlites: Chemistry, Exsolutionmicrostructures, and Thermal History.Contributions to Mineralogy and Petrology, Vol. 78, PP. 118-125.South Africa, Botswana, Tanzania, East Africa, LesothoMicroprobe Analyses, Genesis, Kimberlite
DS1981-0290
1981
Mccallister, R.H.Mccallister, R.H., Nord, G.L.Subcalcic Diopsides from Kimberlites; Chemistry, Ex solution micros tructures and Thermal History.Contributions to Mineralogy and Petrology, Vol. 78, No. 2, PP. 118-125.GlobalGeochemistry, Mineral Chemistry, Geothermometry
DS1981-0291
1981
Mccallister, R.H.Mccallister, R.H., Nord, G.L.JR.Subcalcic Diopsides Fromm Kimberlites: Chemistry, Exsolution Microstructures and Thermal History.Contributions to Mineralogy and Petrology, Vol. 78, PP. 118-125.Lesotho, South Africa, Botswana, Tanzania, East AfricaGenesis
DS1982-0417
1982
Mccallister, R.H.Mccallister, R.H., Meyer, H.O.A.Two-pyroxene Intergrowths from South AfricaProceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, PP. 222-223, (abstract.).South AfricaKoffiefontein, Bellsbank, Kimberlite
DS1984-0515
1984
Mccallister, R.H.Meyer, H.O.A., Mccallister, R.H.Two Pyroxene Megacrysts from South African KimberlitesProceedings of Third International Kimberlite Conference, Vol. 2, PP. 133-144.South Africa, Bellsbank, Frank Smith, KoffiefonteinMineral Chemistry, Analyses, Geothermometry, Geobarometry
DS1975-1131
1979
Mccallister, R.N.Mccallister, R.N., Meyer, H.O.A., Aragon, R.Partial Thermal History of Two Exsolved Clinopyroxenes From the Thaba Putsoa Kimberlite Pipe, Lesotho.Proceedings of Second International Kimberlite Conference, Proceedings Vol. 2, PP. 244-248.LesothoGeothermometry
DS1995-0355
1995
McCallumCoopersmith, H.G., Griffin, W.L., Ryan, Win, McCallumTrace elements in garnets and chromites from Colorado Wyoming kimberlites as a guide to exploration.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 118-120.Colorado, WyomingMantle sampling, metasomatism, emplacement, resortion, Deposit -Colorado Wyoming District
DS202109-1480
2021
McCallum, A.McCallum, A.The importance of luminescence.Gems & Jewelery, Vol. 30, 2, pp. 32-26.Globalluminescence
DS1994-0852
1994
McCallum, I.Joswiak, D.J., McCallum, I., Nelson, B.K.Age and geochemistry of lower crustal granulite xenoliths from minette dikes in central Montana.Geological Society of America (GSA) Abstract Volume, Vol. 26, No. 7, ABSTRACT only p. A296.MontanaIgneous petrology, Minette
DS1985-0502
1985
Mccallum, I.S.O'brien, H.E., Irving, A.J., Mccallum, I.S.Complex Zoning of Clinopyroxene in Shonkinites from Mafic Phonolites, Highwood Mountains, Montana: Evidence for Periodic Mixing with a K Rich Bananitic Magma.Geological Society of America (GSA), Vol. 17, No. 3, P. 187. (abstract.).United States, Montana, Rocky MountainsMineralogy
DS1986-0615
1986
McCallum, I.S.O'Brien, H.E., Irving, A.J., McCallum, I.S.Evolution og minette, lamproite and mafic phonolite magmas in the Highwood Mountains province, Montana USA: geochemical andmineralogicalevidenceProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 199-201MontanaBlank
DS1987-0450
1987
McCallum, I.S.McCallum, I.S.Petrology of the igneous rocksReview of Geophysics, Vol. 25, No. 5, pp. 1021-1042GlobalKimberlites, Carbonatite
DS1987-0543
1987
McCallum, I.S.O'Brien, H.E., Irving, A.J., McCallum, I.S.Geochemical evidence for ancient enriched and eocene arc components In the source region of the Highwood mountains potassic volcanics, MontanaTerra Cognita, Conference abstracts Oceanic and Continental Lithosphere:, Vol. 7, No. 4, Autumn, abstract only p. 621MontanaBlank
DS1989-0686
1989
McCallum, I.S.Irving, A.J., O'Brieb, H.E., McCallum, I.S.Precambrian mantle beneath Montana: geochemical evidence from Eocene volcanics and their xenolithsLpi Technical Report, No. 89-05, pp. 45-46MontanaMantle xenoliths, Age determinations
DS1989-0687
1989
McCallum, I.S.Irving, A.J., O'Brien, H.E., McCallum, I.S.Montana potassic volcanism: geochemical evidence for interaction of asthenopsheric melts and meta-somatically-veinedPrec. subcontinental mantlelithNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 140 Abstract held June 25-July 1MontanaVolcanology, Mantle
DS1992-1024
1992
McCallum, J.McCallum, J.Canada's choice crisis of capital or renewed federalisMC.d. Howe Institute Lecture, June 25, 1992, 42pCanadaEconomics, Capital expenditures
DS1991-1247
1991
McCallum, J.S.O'Brien, H.E., Irvingm A.J., McCallum, J.S.Eocene potassic magmatism in the Highwood Mountains, Montana: petrology, geochemistry and tectonic implicationsJournal of Geophysical Research, Vol. 96, No. B8, July 30, pp. 13, 237-13, 260MontanaHighwood Mountains, Alkaline rocks
DS1982-0330
1982
Mccallum, M.Kirkley, M.B., Mccallum, M.Garnet and Spinel Xenoliths from Colorado Wyoming Kimberlites Reflect Precambrian Tectonic Events.Eos, Vol. 63, No. 45, P. 1134, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1994-1132
1994
McCallum, M. E.McCallum, M. E.Lamproitic(?) diatremes in the Golden area of the Rocky Mountain fold and thrust belt, British Columbia.Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 195-210.British ColumbiaLamproite, Deposit -Golden
DS1994-1133
1994
McCallum, M.EMcCallum, M.E, Huntley, P.M., Falk, R.W., Otter, M.L.Morphological resorption and etch feature trends of diamonds From kimberlite populations Colorado-Wyoming State Line.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 32-50.Colorado, Wyoming, United StatesDiamond morphology, Deposit -Sloan
DS1960-0154
1961
Mccallum, M.E.Houston, R.S., Mccallum, M.E.Mullen Creek-nash Fork Shear Zone, Medicine Bow Mountains, Southeastern Wyoming.Geological Society of America (GSA) SPECIAL PAPER., No. 68, P. 91, (abstract.).United States, Wyoming, Rocky Mountains, Medicine Bow MountainsBlank
DS1960-0478
1964
Mccallum, M.E.Mccallum, M.E.Petrology and Structure of the Precambrian and Post Mississippian Rocks of the East Central Portion of Medicine Bow Mountains.Ph.d. Thesis, University Wyoming, 166P.United States, Wyoming, Rocky Mountains, Medicine Bow MountainsRegional Studies
DS1960-0527
1965
Mccallum, M.E.Chronic, J., Mccallum, M.E., Ferris, C.S.Jr.Lower Paleozoic Rocks in Diatremes in Southern Wyoming and Northern Colorado.Geological Society of America (GSA) SPECIAL PAPER., No. 87, PP. 280-281.United States, Wyoming, Colorado, State Line, Rocky MountainsDiatreme
DS1960-0987
1968
Mccallum, M.E.Mccallum, M.E.The Centennial Ridge Gold-platinum District, Albany County, wyoming.Wyoming Geological Survey Prel. Report, No. 7, 13P.GlobalKimberlite, Medicine Bow Mountains, Rocky Mountains
DS1960-0988
1968
Mccallum, M.E.Mccallum, M.E.Cenozoic History of the East Central Medicine Bow Mountains, Wyoming.Mountain Geology, Vol. 5, No. 2, PP. 69-81.GlobalKimberlite, Medicine Bow Mountains, Rocky Mountains
DS1960-0989
1968
Mccallum, M.E.Mccallum, M.E., Eggler, D.H.Preliminary Report on Mineralogy of Kimberlite Diatremes In the Northern Front Range, Colorado-wyoming.Geological Society of America (GSA) SPECIAL PAPER., No. 121, P. 192, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1960-1090
1969
Mccallum, M.E.Chronic, J., Mccallum, M.E., Ferris, C.S.Jr., Eggler, D.H.Lower Paleozoic Rocks in Diatremes, Southern Wyoming and Northern Colorado.Geological Society of America (GSA) Bulletin., Vol. 80, PP. 149-155.United States, Colorado, Wyoming, Rocky Mountains, State LineDiatreme
DS1970-0350
1971
Mccallum, M.E.Mccallum, M.E., Eggler, D.H.Mineralogy of the Sloan Diatreme a Kimberlite Pipe in Northern Larimer County, Colorado.American Mineralogist., Vol. 56, SEPT.-Oct. No. 9-10, PP. 1735-1749.United States, Colorado, State Line, Rocky MountainsChemical Analyses, Petrography, Xenoliths, Microprobe
DS1970-0584
1972
Mccallum, M.E.Puckett, J.L., Mccallum, M.E., Johnson, R.B., Filson, R.H.Preliminary Geophysical Evaluation of Kimberlitic Diatremesin Northern Colorado and Southern Wyoming.Geological Society of America (GSA), Vol. 4, No. 6, P. 403, (abstract.).Colorado, Wyoming, United States, State Line, Rocky MountainsKimberlite, Geophysics
DS1970-0672
1973
Mccallum, M.E.Eggler, D.H., Mccallum, M.E.Ultramafic Nodules from Colorado Wyoming Kimberlite PipesCarnegie Institute Yearbook, FOR 1972, PP. 446-449.United States, Colorado, Wyoming, State Line, Rocky MountainsPetrography, Mineral Chemistry, Diatreme, Front Range
DS1970-0761
1973
Mccallum, M.E.Mccallum, M.E., Eggler, D.H., Burns, L.K.Kimberlitic Diatremes in Northern Colorado and Southern Wyoming #1International Kimberlite Conference FIRST EXTENDED ABSTRACT VOLUME., PP. 217-220.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1970-0856
1973
Mccallum, M.E.Woolsey, T.S., Mccallum, M.E., Schumm, S.A.Physical Modelling of Diatreme EmplacementInternational Kimberlite Conference FIRST EXTENDED ABSTRACT VOLUME., PP. 235-238.United States, State Line, Rocky MountainsGenesis, Model
DS1970-0903
1974
Mccallum, M.E.Eggler, D.H., Mccallum, M.E.Preliminary Upper Mantle Lower Crust Model of the Colorado Wyoming Front range.Carnegie Institute Yearbook, FOR 1973, PP. 295-300.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1970-0904
1974
Mccallum, M.E.Eggler, D.H., Mccallum, M.E.Colorado Wyoming Kimberlitic Diatremes ,pt. Ii, a View of The Upper Mantle from Nodules.Geological Society of America (GSA), Vol. 6, No. 5, P. 440, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1970-0957
1974
Mccallum, M.E.Mccallum, M.E.Infrared Detection of Kimberlitic Diatremes in Northern Colorado and Southern Wyoming.Contributions To Geology, Vol. 13, No. 1, PP. 17-18.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1970-0958
1974
Mccallum, M.E.Mccallum, M.E., Eggler, D.H., Burns, L.K.Colorado Wyoming Kimberlitic Diatremes: Pt. I, General Geology and Petrography.Geological Society of America (GSA), Vol. 6, No. 5, P. 457, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0071
1975
Mccallum, M.E.Eggler, D.H., Mccallum, M.E.A Field Test of Geothermometers and BarometersInternational Conference ON GEOTHERMOMETRY, EXTENDED ABSTRACTS, BOETTCH, 3P.United States, Colorado, Wyoming, Rocky MountainsBlank
DS1975-0072
1975
Mccallum, M.E.Eggler, D.H., Mccallum, M.E.Diamond Bearing Peridotite Nodule in Wyoming Kimberlite PipeGeological Society of America (GSA), Vol. 7, No. 7, P. 1065, (abstract.).United States, Wyoming, State Line, Rocky MountainsBlank
DS1975-0131
1975
Mccallum, M.E.Mccallum, M.E., Eggler, D.H., Burns, L.K.Kimberlitic Diatremes in Northern Colorado and Southern Wyoming #2Physics and Chemistry of the Earth, Vol. 9, PP. 149-161.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0132
1975
Mccallum, M.E.Mccallum, M.E., Smith, C.B., Burns, L.K., Eggler, D.H., Braddoc.Kimberlite Diatremes and Others Iron Mountain Area, Laramierange, Wyoming.Geological Society of America (GSA), Vol. 7, No. 5, P. 628 (abstract.).United States, Wyoming, State Line, Rocky MountainsBlank
DS1975-0213
1975
Mccallum, M.E.Woolsey, T.S., Mccallum, M.E., Schumm, S.A.Modeling of Diatreme Emplacement by FluidizationPhysics and Chemistry of the Earth, Vol. 9, PP. 29-42.United StatesBreccia
DS1975-0273
1976
Mccallum, M.E.Eggler, D.H., Mccallum, M.E.A Geotherm from Megacrysts in the Sloan Kimberlite Pipes, ColoradoCarnegie Institute Yearbook, FOR 1975 PP. 538-541.United States, Colorado, State Line, Rocky MountainsBlank
DS1975-0274
1976
Mccallum, M.E.Eggler, D.H., Mccallum, M.E., Smith, C.B.A Geotherm from Megacrysts in Colorado-Wyoming Kimberlite Pipes.Geological Society of America (GSA), Vol. 8, No. 6, P. 851, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0334
1976
Mccallum, M.E.Mccallum, M.E.An Emplacement Model to Explain Contrasting Mineral Assemblages in Adjacent Kimberlite Pipes.Journal of GEOLOGY, Vol. 84, PP. 673-684.United States, State Line, Rocky MountainsGenesis, Model
DS1975-0335
1976
Mccallum, M.E.Mccallum, M.E., Eggler, D.H.Diamonds in an An Upper Mantle Peridotite Nodule from Kimberlite in Southern Wyoming.Science., Vol. 192, No. 4236, PP. 253-256.United States, Wyoming, State Line, Rocky MountainsBlank
DS1975-0336
1976
Mccallum, M.E.Mccallum, M.E., Hedge, C.E.Rubidium-strontium Ages of Granitic Rocks in the Rawah Batholith, medicine Bow Mountains, Northern Colorado.Isochron West., No. 17, PP. 33-37.United States, State Line, Colorado, WyomingGeochronology, Batholites
DS1975-0337
1976
Mccallum, M.E.Mccallum, M.E., Mabarak, C.D.Diamond in Kimberlitic Diatremes of Northern ColoradoGeology, Vol. 4, PP. 467-469.United States, Colorado, State Line, Rocky MountainsKimberlite, State Line, Rocky Mountains
DS1975-0338
1976
Mccallum, M.E.Mccallum, M.E., Mabarak, C.D.Diamond in State Line Kimberlite Diatremes Albany County, Wyoming and Larimer County, Colorado.Wyoming Geological Survey Report Inv., No. 12, 36P.United States, Colorado, Wyoming, State Line, Rocky MountainsProspecting, Genesis, Distribution, Petrography, Mineralogy
DS1975-0339
1976
Mccallum, M.E.Mccallum, M.E., Mabarak, C.D.Diamond from Kimberlite Diatremes in Northern Colorado and Southern Wyoming.Geological Society of America (GSA), Vol. 8, No. 5, P. 609. (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0340
1976
Mccallum, M.E.Mccallum, M.E., Woolsey, T.S., Schumm, S.A.A Fluidization Mechanism for Subsidence of Bedded Tuffs in Diatremes and Related Volcanic Vents.Bulletin. VOLCAN., Vol. 39, No. 4, PP. 512-527.GlobalBreccia
DS1975-0341
1976
Mccallum, M.E.Mccallum, M.E., Woolsey, T.S., Schumm, S.A.A Fluidized Mechanism for Subsidence of Bedded Tuffs in Diatremes and Related Volcanic Vents.Bulletin. VOLCANOLOGIQUE., Vol. 39, No. 4, PP. 512-527.United States, Colorado Plateau, State Line, Rocky MountainsBlank
DS1975-0414
1976
Mccallum, M.E.Smith, C.B., Mccallum, M.E., Eggler, D.H.Clinopyroxene Ilmenite Intergrowths from the Iron Mountain kimberlite District, Wyoming.Carnegie Institute Yearbook, FOR 1975 PP. 542-544.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0415
1976
Mccallum, M.E.Smith, C.B., Mccallum, M.E., Eggler, D.H.Peridotite and Clinopyroxene Ilmenite Nodules from a Pipe In the Iron Mountain, Wyoming Kimberlite District.Geological Society of America (GSA), Vol. 8, No. 5, P. 631. (abstract.).United States, Wyoming, State Line, Rocky MountainsBlank
DS1975-0499
1977
Mccallum, M.E.Donnelly, M.E., Mccallum, M.E.Petrology and Structure of the Southern Portion of the Mullen Creek Mafic Complex, Medicine Bow Mountains, Wyoming.Geological Society of America (GSA), Vol. 9, No. 6, PP. 72-721, (abstract.).United States, Wyoming, Rocky Mountains, Medicine Bow MountainsBlank
DS1975-0502
1977
Mccallum, M.E.Eggler, D.H., Mccallum, M.E., Smith, C.B.Discrete Nodule Assemblages in Kimberlites from the Northern Colorado and Southern Wyoming Evidence for a Diapiric Origin of Kimberlite.International Kimberlite Conference SECOND, EXTENDED ABSTRACT VOLUME., United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0561
1977
Mccallum, M.E.Mccallum, M.E., Eggler, D.H.Field Guide for the Sloan and Nix Kimberlites in the Southern Portion of the Colorado-Wyoming State Line Kimberlite District #2International Kimberlite Conference SECOND, FIELD GUIDE TRIP No. 4, PP. 182-209.United States, State Line, Colorado, Wyoming, Rocky MountainsKimberley, Distribution
DS1975-0562
1977
Mccallum, M.E.Mccallum, M.E., Eggler, D.H., Coopersmith, H.G., Smith, C.B.M.Colorado-Wyoming State Line DistrictInternational Kimberlite Conference SECOND FIELD EXCURSION SEPT. 25-27TH., 25P.United States, Colorado, Wyoming, State Line, Rocky MountainsKimberley, Guidebook
DS1975-0563
1977
Mccallum, M.E.Mccallum, M.E., Eggler, D.H., Smith, C.B.Discrete Nodule Assemblages in Kimberlites from Northern Colorado and Southern Wyoming.International Kimberlite Conference SECOND EXTENDED ABSTRACT VOLUME., United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0564
1977
Mccallum, M.E.Mccallum, M.E., Kirkley, M.B., Padgett, J.P., Eggler, D.H.Textural and Mineral Compositional Ranges of Ultramafic Nodules from Kimberlites of Northern Colorado and Southern Wyoming #1International Kimberlite Conference SECOND EXTENDED ABSTRACT VOLUME., United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0565
1977
Mccallum, M.E.Mccallum, M.E., Mabarak, C.D., Coopersmith, H.G.Diamonds from Kimberlite in the Colorado Wyoming State Linedistrict.International Kimberlite Conference SECOND EXTENDED ABSTRACT VOLUME., United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-0566
1977
Mccallum, M.E.Mccallum, M.E., Naeser, C.W.Fission Track Ages of Tertiary Intrusive Rocks in the Manhattan Mining District, Northern Front Range Colorado.Isochron West., No. 18, PP. 1-4.United States, Colorado, State Line, Rocky MountainsBlank
DS1975-0581
1977
Mccallum, M.E.Mussard, D.E., Mccallum, M.E.Petrology and Geochemistry of Boulder Creek Equivalent (?) Felsic intrusives in the Medicine Bow Mountains, Southern Wyoming.Geological Society of America (GSA), Vol. 9, No. 6, P. 751, (abstract.).GlobalKimberlite, Medicine Bow Mountains Rocky Mountains
DS1975-0583
1977
Mccallum, M.E.Naeser, C.W., Mccallum, M.E.Fission Track Dating of Kimberlitic ZirconsInternational Kimberlite Conference SECOND EXTENDED ABSTRACT VOLUME., United States, State Line, Rocky MountainsIsotope
DS1975-0624
1977
Mccallum, M.E.Smith, C.B., Mccallum, M.E., Coopersmith, H.G., Eggler, D.H.Petrography, Petrology and Chemistry of Kimberlite from The colorado-wyoming State Line and Iron Mountain Wyoming Districts.International Kimberlite Conference SECOND, EXTENDED ABSTRACT VOLUME., United States, Wyoming, State Line, Rocky MountainsBlank
DS1975-0804
1978
Mccallum, M.E.Mccallum, M.E., Smith, C.B.Minor and Trace Element Contents of Kimberlite of the Frontrange, Colorado and Wyoming.United States Geological Survey (USGS) OPEN FILE Report, No. 78-1011, 23P.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1005
1979
Mccallum, M.E.Eggler, D.H., Mccallum, M.E., Smith, C.B.Megacryst Assemblages in Kimberlite from Northern Colorado And Southern Wyoming: Petrology Geothermometry-barometry And areal Distribution.International Kimberlite Conference SECOND Proceedings, Vol. 2, PP. 213-226.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1063
1979
Mccallum, M.E.Hausel, W.D., Mccallum, M.E., Woodzick, T.L.Preliminary Report on Exploration for Diamondiferous Kimberlites Colorado and Wyoming.Colorado Mining Association Yearbook, PP. 109-122.United States, Colorado, Wyoming, State Line, Rocky MountainsAlluvial Sampling, Prospecting, Geophysics, Kimberlite
DS1975-1064
1979
Mccallum, M.E.Hausel, W.D., Mccallum, M.E., Woodzick, T.L.Exploration for Diamond Bearing Kimberlite in Colorado and Wyoming-anWyoming Geological Survey Report Investigations, No. 19, 29P.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1065
1979
Mccallum, M.E.Hausel, W.D., Mccallum, M.E., Woodzick, T.L.Update on Exploration for Diamonds in Colorado Wyoming Kimberlite Province.A.a.p.g.s.e.p.m. Meeting, Vol. 63, No. 5, P. 830, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1113
1979
Mccallum, M.E.Leighton, V.L., Mccallum, M.E.Rapid Evaluation of Heavy Minerals in Stream Sediments of The Prairie Divide Area of Northern Colorado. a Tool for Kimberlite Exploration.United States Geological Survey (USGS) OPEN FILE., No. 79-761, 1 MAP WITH ABSTRACT AND RESULTS.United States, Colorado, Wyoming, State LineGeochemistry, Prospecting, Heavy Minerals, Techniques
DS1975-1132
1979
Mccallum, M.E.Mccallum, M.E.Geochemical Prospecting for Kimberlite in the Colorado Wyoming State Line District.Geological Society of America (GSA), Vol. 11, No. 6, P. 279, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsGeochemistry
DS1975-1133
1979
Mccallum, M.E.Mccallum, M.E., Coopersmith, H.G.Diamonds from Kimberlite in the Colorado-Wyoming State Linedistrict.International Kimberlite Conference SECOND, PP. 42-58.United States, Colorado, Wyoming, State Line, Rocky MountainsDiatreme
DS1975-1134
1979
Mccallum, M.E.Mccallum, M.E., Eggler, D.H.Field Guide for the Sloan and Nix Kimberlites in the Southern Portion of the Colorado-Wyoming State Line Kimberlite District #1Unknown, PP. 181-209.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1135
1979
Mccallum, M.E.Mccallum, M.E., Kirkley, M.B., Padgett, J.L., Eggler, D.H.Textural and Mineral Compositional Ranges of Ultramafic Nodules from Kimberlites of Northern Colorado and Southern Wyoming #2Kimberlite Symposium Ii, Cambridge, England., PP. 1-5.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1136
1979
Mccallum, M.E.Mccallum, M.E., Kirkley, M.B., Padgett, J.P.Compositional and Textural Ranges of Peridotite Nodules From Kimberlites of the Colorado-Wyoming State Line District.Geological Society of America (GSA), Vol. 11, No. 6, P. 279, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1137
1979
Mccallum, M.E.Mccallum, M.E., Mabarak, C.D., Coopersmith, H.G.Diamonds from Kimberlites in the Colorado Wyoming State Line District.International Kimberlite Conference SECOND Proceedings, Vol. 1, PP. 42-53.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1975-1223
1979
Mccallum, M.E.Smith, C.B., Mccallum, M.E., Coopersmith, H.G., Eggler, D.H.Petrochemistry and Structure of Kimberlites in the Front Range and Laramie Range Colorado-wyoming.International Kimberlite Conference SECOND Proceedings, Vol. 1, PP. 178-189.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1980-0166
1980
Mccallum, M.E.Hausel, W.D., Mccallum, M.E.General Review of Northern Colorado and Southeastern Wyoming Kimberlites ,diamonds and Related Research Activity.Colorado Geological Survey, No. 8, PP. 106-115.United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1980-0191
1980
Mccallum, M.E.Kirkley, M.B., Mccallum, M.E., Eggler, D.H.Mineral Chemistry and Textural Correlations in Peridotite Nodules from Northern Colorado-southern Wyoming Kimberlites.Geological Society of America (GSA), Vol. 12, No. 6, P. 276, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1980-0227
1980
Mccallum, M.E.Mccallum, M.E., Ater, P.C., Eggler, D.H., Smith, C.B., Shannon.Mantle Eclogite Nodules from Northern Colorado and Southernwyoming.Geological Society of America (GSA), Vol. 12, No. 3, P. 280, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1981-0097
1981
Mccallum, M.E.Bradley, S.D., Mccallum, M.E.Lower Crustal Granulite Facies and Related Xenoliths from Colorado-Wyoming State Line Kimberlites.Geological Society of America (GSA), Vol. 13, No. 4, P. 192, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1981-0292
1981
Mccallum, M.E.Mccallum, M.E.Mineralogical and Textural Genetic Classification of Northern Colorado-southern Wyoming Kimberlites.Geological Society of America (GSA), Vol. 13, No. 4, P. 219, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsGenesis
DS1982-0076
1982
Mccallum, M.E.Ater, P.C., Mccallum, M.E., Eggler, D.H.Petrology and Geochemistry of Mantle Eclogite Xenoliths From Colorado-Wyoming Kimberlites.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, PP. 221-222, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1982-0113
1982
Mccallum, M.E.Bradley, S.D., Mccallum, M.E.Lower Crustal Xenoliths from Colorado-Wyoming State Line Kimberlites.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 236, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1982-0132
1982
Mccallum, M.E.Carlson, J.A., Johnson, R.B., Mccallum, M.E., Padgett, J.P.Evaluation of Geophysical Techniques for Diatreme Delineation in the Colorado-Wyoming Kimberlite Province. #1Proceedings of Third International Kimberlite Conference, TERRA, Vol. 2, No. 3, P. 203, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsKimberlite, Geophysics, Groundmag, Electromagnetic, Radioactivity
DS1982-0133
1982
Mccallum, M.E.Carlson, J.A., Mccallum, M.E.Evaluation of Geophysical Techniques for Diatreme DelineatioThe Journal of The Colorado-wyoming Academy of Science, Vol. 14, No. 1, P. 27, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsKimberlite, Geophysics
DS1982-0331
1982
Mccallum, M.E.Kirkley, M.B., Mccallum, M.E., Eggler, D.H.Mantle Garnet-spinel Transition Zone Demonstrated by Xenoliths from Colorado-Wyoming Kimberlites.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, PP. 218-219, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1982-0418
1982
Mccallum, M.E.Mccallum, M.E., Coopersmith, H.G., Hodge, C.W.Mineralogical and Textural Genetic Classification of Kimberlites in Northern Colorado and Southern Wyoming, United States (us)Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 209, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1982-0419
1982
Mccallum, M.E.Mccallum, M.E., Donnelly, M.E., Mussard, D.E.Generalized Geologic Map and Rapid Whole Rock, Minor ElementUnited States Geological Survey (USGS) OPEN FILE REPORT., IN PREP.GlobalKimberlite, Medicine Bow Mountains Rocky Mountains
DS1982-0420
1982
Mccallum, M.E.Mccallum, M.E., Mussard, D.E.Generalized Geologic Map and Rapid Whole Rock, Minor ElementUnited States Geological Survey (USGS) OPEN FILE REPORT., IN PREP.GlobalKimberlite, Medicine Bow Mountains
DS1982-0486
1982
Mccallum, M.E.Padgett, J.P., Mccallum, M.E., Meyer, H.O.A.Relationship between Geochemistry and Color of Garnet Xenocrysts from Colorado-Wyoming Kimberlites.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 224, (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsBlank
DS1982-0570
1982
Mccallum, M.E.Smith, C.B., Mccallum, M.E., Hedge, C.E.Rubidium-strontium Isotopic Ratios in Selected Lower Crust Upper Mantle nodules from Colorado-Wyoming Kimberlites.United States Geological Survey (USGS) OPEN FILE Report, No. 82-0178, 22P.Colorado, WyomingKimberlite, State Line, Rocky Mountains
DS1982-0643
1982
Mccallum, M.E.Woodzick, T.L., Mccallum, M.E.A Teledetective Study of Kimberlite Regions in North America ( Colorado-wyoming),east Africa ( Mwadui ),and Siberia (mir). #1Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 203, (abstract.).United States, Colorado, Wyoming, East Africa, Russia, Tanzania, Rocky MountainsKimberlite, Geophysics, Remote Sensing
DS1983-0355
1983
Mccallum, M.E.Kirkley, M.B., Mccallum, M.E., Eggler, D.H.Coexisting Garnet and Spinel in Upper Mantle Xenoliths From colorado Wyoming Kimberlites: Appendix.Annales Scientifiques De L' Universite De Clermont-ferrand Ii, No. 74, PP. 149-156.United States, State Line, Colorado, Wyoming, Rocky MountainsAnalyses
DS1983-0438
1983
Mccallum, M.E.Mccallum, M.E., Lincoln, J.B.Review of Kimberlite Exploration and Evaluation MethodsGeological Survey WYOMING, PUB. INFO. Circular No. 19, PP. 8-10.United States, Wyoming, State Line, Colorado, Rocky MountainsSampling, Heavy Minerals, Soils
DS1983-0447
1983
Mccallum, M.E.Memmi, J.M., Mccallum, M.E., Hausel, W.D.Preliminary Results of Resistivity Investigations of Colorado Wyoming Kimberlite Diatremes.Geological Society of America (GSA), Vol. 15, No. 5, P. 317. (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsGeophysics, Kimberlite
DS1984-0119
1984
Mccallum, M.E.Ater, P.C., Eggler, D.H., Mccallum, M.E.Petrology and Geochemistry of Mantle Eclogite Xenoliths From Colorado Wyoming Kimberlites: Recycled Ocean Crust?Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 309-318.United States, Colorado, Wyoming, State LinePetrography, Mineral Chemistry, Garnets, Analyses, Whole Rock Composition
DS1984-0172
1984
Mccallum, M.E.Bradley, S.D., Mccallum, M.E.Granulite Facies and Related Xenoliths from Colorado Wyoming Kimberlite.Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 205-217.United States, State Line, California, Colorado, WyomingPetrography, Whole Rock Chemistry
DS1984-0180
1984
Mccallum, M.E.Carlson, J.A., Johnson, R.B., Mccallum, M.E., Campbell, D.L.P.Evaluation of Geophysical Techniques for Diatreme Delineation in the Colorado Wyoming Kimberlite Province. #2Proceedings of Third International Kimberlite Conference, Vol. 1, PP. 21-32.United States, Colorado, Wyoming, State Line, Rocky MountainsGeophysics, Kimberlite, Electromagnetic, Ground, Magnetics, Vlf
DS1984-0411
1984
Mccallum, M.E.Kirkley, M.B., Mccallum, M.E., Eggler, D.H.Coexisting Garnet and Spinel in Upper Mantle Xenoliths From colorado Wyoming Kimberlites.Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 84-96.United States, State Line, Colorado, Wyoming, California, Rocky MountainsWebsterite, Lherzolite, Petrography, Mineral Chemistry, Analyses
DS1984-0516
1984
Mccallum, M.E.Meyer, H.O.A., Mccallum, M.E.Mineral Inclusions in Diamonds from Kimberlites in Colorado and Wyoming.Geological Society of America (GSA), Vol. 16, No. 6, P. 595. (abstract.).United States, Colorado, Wyoming, State Line, Rocky MountainsMineralogy
DS1984-0773
1984
Mccallum, M.E.Woodzick, T.L., Mccallum, M.E.A Teledetective Study of Kimberlite Regions in North America (colorado- Wyoming),east Africa (mwadui) and Siberia (mir). #2Proceedings of Third International Kimberlite Conference, Vol. 1, PP. 5-20.United States, Colorado, Wyoming, State Line, Russia, East Africa, TanzaniaGeophysics, Kimberlite, Remote Sensing, Lineaments
DS1985-0171
1985
Mccallum, M.E.Eggler, D.H., Mccallum, M.E., Kirkley, M.B.Kimberlite-transported Nodules from Colorado Wyoming Enrichment of Shallow Lithosphere by MetasomatismGeological Society of America (GSA), Vol. 17, No. 3, P. 157. (abstract.).United States, Colorado, Wyoming, State LineAriiegite, Griquaite, Websterite
DS1985-0274
1985
Mccallum, M.E.Hausel, W.D., Mccallum, M.E., Roberts, J.T.The Geology, Diamond Testing Procedures, and Economic Potential of the Colorado Wyoming Kimberlite Province- a Review.Wyoming Geological Survey Report Inv., No. 31, 23P.United States, State Line, Colorado, WyomingHistory, Geology, Location, Diamond Occurrences, Prospecting
DS1985-0428
1985
Mccallum, M.E.Mccallum, M.E.Experimental Evidence for Fluidization Processes in Breccia pipe Formation.Econ.geol., Vol. 80, No. 6, PP. 1523-1543.United States, State Line, Wyoming, Colorado, Rocky Mountains, Utah, MontanaMule Ear, Butte, Diatreme, Breccia Pipes, Review
DS1986-0541
1986
McCallum, M.E.McCallum, M.E.Oxide minerals in Chicken Park kimberlite, north ColoradoProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 63-65ColoradoMineral chemistry, Spinel analyses
DS1986-0558
1986
McCallum, M.E.Meen, J.K., Eggler, D.H., McCallum, M.E.Proterozoic granulite xenoliths from Ming bar diatremeGeological Society of America (GSA) Abstract Volume, Vol. 18, No. 6, p. 692. (abstract.)MontanaBlank
DS1986-0567
1986
McCallum, M.E.Meyer, H.O.A., McCallum, M.E.Mineral inclusions in diamonds from the Sloan kimberlites, ColoradoJournal of Geology, Vol. 94, pp. 600=612ColoradoDiamond morphology, Inclusions
DS1987-0181
1987
McCallum, M.E.Eggler, D.H., Dudas, F.O., Hearn, B.C., McCallum, M.E., McGee, E.S.Lithosphere of the continental United States: Xenoliths in Kimberlites and other alkaline magmasin: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 41-58United States, Montana, Colorado Wyoming, Kansas, Arkansas, MichiganTennessee, Kentucky, Pennsylvania, New York, Wyoming, Arizon
DS1987-0182
1987
McCallum, M.E.Eggler, D.H., McCallum, M.E., Kirkley, M.B.Kimberlite transported nodules from Colorado-Wyoming: a recordof enrichment of shallow portions of an infertile lithosphereMantle metasomatism and alkaline magmatism, edited E. Mullen Morris and, No. 215, pp. 77-90Colorado, WyomingState Line
DS1989-0969
1989
McCallum, M.E.McCallum, M.E.Oxide minerals in Chicken Park kimberlite, northern ColoradoGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 241-263ColoradoDeposit -Chicken Park, Geochemistry
DS1990-0728
1990
McCallum, M.E.Huntley, P.M., McCallum, M.E.Morphology and surface textures of diamonds from selected kimberlite occurrences in the Colorado-Wyoming State Line DistrictGeological Society of America (GSA) Abstract Volume, held Jackson Wyoming, Vol. 22, No. 6, April p. 15. Abstract onlyColorado, WyomingDiamond morphology, Diamond resorption
DS1991-0618
1991
McCallum, M.E.Grubb, M.D., McCallum, M.E.Genesis of diamond placers on the Guiana shield, South AmericaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 151-153GuyanaIssineru-Enachu district, Roraima Group, geomorphology
DS1991-1088
1991
McCallum, M.E.McCallum, M.E.Lamproitic (?) diatremes in the Golden area of the Rocky Mountain fold and thrust belt, British Columbia, Canada #1The Canadian Mining and Metallurgical Bulletin (CIM Bulletin) ., Session, Vol. 84, No. 947, March p. 90. AbstractBritish ColumbiaLamproite, Diatremes
DS1991-1089
1991
McCallum, M.E.McCallum, M.E.Lamproitic (?) diatremes in the Golden area of the Rocky Mountain Fold and thrust Belt, British Columbia, Canada #2Proceedings of Fifth International Kimberlite Conference held Araxa June, pp. 257-260British ColumbiaPetrology, Geochemistry
DS1991-1090
1991
McCallum, M.E.McCallum, M.E., Huntly, P.M., Falk, R.W., Otter, M.L.Morphological, resorption and etch feature trends of diamonds From kimberlites within the Colorado Wyoming State Line District, USAProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 261-263Colorado, WyomingDiamond morphology, Diamond inclusions
DS1991-1124
1991
McCallum, M.E.Memmi, J.M., McCallum, M.E.Finite element modeling of resistivity dat a from kimberlites inColorado-Wyoming, USAProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 276-278Colorado, WyomingGeophysics -resistivity
DS1991-1125
1991
McCallum, M.E.Memmi, J.M., McCallum, M.E.Enhancement of geophysical dat a for kimberlite exploration at IronMountain, Wyoming, USAProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 273-275WyomingGeophysics-magnetics, Conductivity
DS1991-1276
1991
McCallum, M.E.Otter, M.L., Gurney, J.J., McCallum, M.E.A physical characterization of the Sloan diamondsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 320-321Colorado, WyomingState Line, diamond inclusions, Diamond morphology
DS1991-1820
1991
McCallum, M.E.Vos, W.P., McCallum, M.E.Application of simple paramagnetic susceptibility to rapid discrimination of ilmenite compositions in exploration for kimberlite in the Colorado-WyomingProvince, United StatesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 443-445Colorado, WyomingGeophysics -magnetics, Picroilmenite
DS1993-0984
1993
McCallum, M.E.McCallum, M.E., Neal, C.R.Petrogenesis of chromium-rich and chromium-poor megacrysts: seperate parental melts from a single source?American Geophysical Union, EOS, supplement Abstract Volume, October, Vol. 74, No. 43, October 26, abstract p. 637.Colorado, WyomingMegacrysts, Experimental petrology
DS1993-0985
1993
McCallum, M.E.McCallum, M.E., Vos, W.P.Ilmenite signatures: utilization of paramagnetic and chemical properties In kimberlite exploration.Diamonds: exploration, sampling and evaluation proceedings of a short, pp. 109-146.Northwest Territories, Colorado, WyomingIlmenites, Geophysics -magnetics
DS1993-1024
1993
McCallum, M.E.Meyer, H.O.A., McCallum, M.E.Diamonds and their sources in the Venezuelan portion of the Guyana shieldEconomic Geology, Vol. 88, No. 5, August pp. 989-998.Venezuela, Guyana, BrazilAlluvial diamonds, Source region for diamonds
DS1994-1167
1994
McCallum, M.E.Memmi, J.M., McCallum, M.E.Finite element modeling of resistivity dat a from kimberlite intrusions inWyoming, USAProceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 382-388.Wyoming, United StatesGeophysics -resistivity
DS1994-1319
1994
McCallum, M.E.Otter, M.L., McCallum, M.E., Gurney, J.J.A physical characterization of the Sloan (Colorado) diamonds using arevised diamond description scheme.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 15-31.Colorado, United StatesPetrology, Deposit -Sloan
DS1995-1191
1995
McCallum, M.E.McCammon, C.A., Chinn, I.L., Gurney, J.J., McCallum, M.E.Determination of the ferric iron content of diamond inclusions from George Creek - Mossbauer spectroscopyProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 359-361.WyomingDiamond inclusions, Deposit -George Creek
DS1995-1777
1995
McCallum, M.E.Smith, C.B., McCallum, M.E.Strontium and neodymium isotopic character of Colorado-Wyoming kimberlites: evidence for lithospheric variability...Eos, Vol. 76, No. 46, Nov. 7. p.F642. Abstract.Colorado, Wyoming, State LineGeochronology, Front Range, Sloan, Chicken Park, Green, Estes, Iron Mt
DS1998-0250
1998
McCallum, M.E.Chinn, I.L., McCallum, M.E., Harris, Milledge, GurneyCO2 bearing diamonds in eclogite xenoliths from the Sloan 2 kimberlite, Colorado.7th International Kimberlite Conference Abstract, p. 155.Colorado, WyomingEclogite xenoliths, Deposit - Sloan 2
DS1998-0971
1998
McCallum, M.E.McCammon, C.A., Chinn, I.L., McCallum, M.E.Ferric iron content of mineral inclusions in diamonds from George Creek determined - Mossbauer spectroscopy.Contributions to Mineralogy and Petrology, Vol. 133, No. 1-2, pp. 30-37.ColoradoMineral inclusions, Deposit - George Creek
DS200612-0883
2006
McCallum, M.E.McCallum, M.E.The Snap Lake kimberlite sheet complex, Northwest Territories, Canada.Emplacement Workshop held September, 5p. extended abstractCanada, Northwest TerritoriesDyke system model
DS1990-0186
1990
McCallum, R.E.Bell, J.S., McCallum, R.E.In situ stress in the Peace River Arch area, western CanadaGeology of the Peace River Arch, ed. Sc.C. O'Connell, J.S. Bell, Bulletin. Can., Vol. 38A, Special Volume, December pp. 270-281AlbertaPeace River area, Tectonics, structure
DS1996-0912
1996
McCalpin, J.P.McCalpin, J.P.PaleoseismologyAcademic Press, 576p. approx. 90.00GlobalBook - ad, Paleoseismology
DS1998-1021
1998
McCammonMitchell, R.H., Choi, J-B., Hawthorne, F.C., McCammonLatrappite: a re-investigationCan. Mineralog., Vol. 36, No. 1, Feb pp. 107-116.Quebec, Arkansas, GermanyCarbonatite, Mineralogy
DS201112-0698
2011
McCammonMookerjee, M., Nakajima, Y., Steinle-Neumann, G., Glazyrin, K., Wu, X., Dubrovinsky, McCammon, ChumakovHigh pressure behaviour of iron carbide (Fe[7]C[3j] at inner core conditions.Journal of Geophysical Research, Vol. 116, B4, B04201.MantleHP core
DS1993-0986
1993
McCammon, C.McCammon, C.Effect of pressure on the composition of the lower mantle end member FexOScience, Vol. 259, January 1, pp. 66-68.GlobalMantle, Oxygen fugacity
DS1993-0987
1993
McCammon, C.McCammon, C., et al.Determining the mantle oxidation state through Mossbauer analysis of high pressure phases in the system iron-FeO-MgO-SiO2.Geological Association of Canada (GAC), Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Annual Meeting, Abstract, Abstract Vol. p. A68.MantleExperimental petrology
DS1996-0398
1996
McCammon, C.Dyer, M.D., McCammon, C., Schaefer, M.W.Mineral spectroscopy: a tribute to Roger C. BurnsGeochemical Society, Book $ 35.00 United StatesGlobalSpectroscopy, Book -ad
DS1997-0748
1997
McCammon, C.McCammon, C.Perovskite as a possible sink for ferric iron in the lower mantleNature, Vol. 387, No. 6634, June 12, pp. 694-5.MantlePerovskite
DS1997-0749
1997
McCammon, C.McCammon, C., Hutchison, M., Harris, J.Ferric iron content of mineral inclusions in diamonds from Sao Luiz: a view from the lower mantle.Science, Vol. 278, No. 5337, Oct. 17, pp. 434-BrazilDiamond inclusions, Deposit - San Luiz
DS2001-0745
2001
McCammon, C.McCammon, C.Geophysics : deep diamond mysteriesScience, No. 5531, Aug. 3, pp. 813-4.MantleGeophysics
DS2002-0186
2002
McCammon, C.Bolfan Casanova, N., Mackwell, S., Keppler, H., McCammon, C., Rubie, D.C.Pressure dependence of H solibility in magnesiowustite up to 25 GPa: implications forGeophysical Research Letters, Vol. 29,10,May15,pp.89-MantleGeochemistry
DS2002-0660
2002
McCammon, C.Harte, B., Harris, J.W., Wilding, M., Sautter, V., McCammon, C.Eclogite garnetite inclusions in diamonds from the Sao Luiz area, Brasil18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.74.BrazilGarnet mineralogy
DS2002-1023
2002
McCammon, C.McCammon, C., Lauterbach, S., Van Akern, P., Langenhorst, F., Seifert, F.EELS studies of lower mantle mineral assemblages: a window to redox conditions18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.77.MantleUHP mineralogy - perovskite
DS2002-1537
2002
McCammon, C.Stachel, T., Harris, J.W., McCammon, C.Inclusions in ultra deep diamonds - tracers of ancient slabs?18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.74.MantleUHP mineralogy
DS2002-1751
2002
McCammon, C.Xu, Y., McCammon, C.Evidence for ionic conductivity in lower mantle. ( Mg Fe Si Al O3) perovskiteJournal of Geophysical Research, Vol. 107, 10, ECV 11 DOI 10.1029/2001JB000677MantleGeophysics - seismics
DS2002-1752
2002
McCammon, C.Xu, Y., McCammon, C.Evidence for ionic conductivity in lower mantle perovskiteJournal of Geophysical Research, Oct. 29, 10.1029/2001JB000677.MantlePerovskite
DS2003-0742
2003
McCammon, C.Kopylova, M.G., McCammon, C.Composition and the redox state of the Slave peridotitic mantle8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractNorthwest TerritoriesDiamond exploration, Geochemistry
DS200412-0218
2004
McCammon, C.Bromiley, G., Hilaret, N., McCammon, C.Solubility of hydrogen and ferris iron in rutile and TiO1(II): implications for phase assemblages during ultrahigh pressure metaGeophysical Research Letters, Vol. 31, 4, Feb. 28, DOI 1029/2004 GLO19430MantleSilica polymorphs in the lower mantle
DS200412-0219
2004
McCammon, C.Bromiley, G.D., Keppler, H., McCammon, C., Bromiley, F.A., Jacobsen, S.D.Hydrogen solubility and speciation in natural gem quality chromian diopside.American Mineralogist, Vol. 89, 6, pp. 941-949.TechnologyPetrology, experimental ( not specific to diamonds)
DS200412-1035
2003
McCammon, C.Kopylova, M.G., McCammon, C.Composition and the redox state of the Slave peridotitic mantle.8 IKC Program, Session 8, AbstractCanada, Northwest TerritoriesDiamond exploration Geochemistry
DS200412-1256
2004
McCammon, C.McCammon, C., Kopylova, M.G.A redox profile of the Slave mantle and oxygen fugacity control in the cratonic mantle.Contributions to Mineralogy and Petrology, Vol. 148, 1, pp. 55-68.Canada, Northwest TerritoriesMineral chemistry - redox
DS200512-0699
2005
McCammon, C.McCammon, C.The paradox of mantle redox.Science, Vol. 308, 5723, May 6, p. 807-8.MantleMelting
DS200512-1179
2005
McCammon, C.Williams, H.M., Peslier, A.H., McCammon, C., Halliday, A.N., Levasseur, S., Teutsch, N., Burg, J.P.Systematic iron isotope variations in mantle rocks and minerals: the effects of partial melting and oxygen fugacity.Earth and Planetary Science Letters, Advanced in press,MantleMelting
DS200512-1180
2005
McCammon, C.Williams, H.M., Peslier, A.H., McCammon, C., Halliday, A.N., Levasseur, S., Teutsch, N., Burg, J.P.Systematic iron isotope variations in mantle rocks and minerals. The effects of partial melting and oxygen fugacity.Earth and Planetary Science Letters, Vol. 235, 1-2, pp. 435-452.MantleGeochronology, melting
DS200612-0884
2006
McCammon, C.McCammon, C.Microscopic properties to macroscopic behaviour: the influence of iron electronic state.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p.MantleOxidation and spin state
DS200712-0647
2007
McCammon, C.Longo, M., McCammon, C.Iron oxidation state in (Mg,Fe)O: calibration of the 'flank method' using synthetic samples and application to natural diamond inclusions.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.190.MantleDiamond morphology, inclusions
DS200712-0648
2007
McCammon, C.Longo, M., McCammon, C.Iron oxidation state in (Mg,Fe)O: calibration of the 'flank method' using synthetic samples and application to natural diamond inclusions.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.190.MantleDiamond morphology, inclusions
DS200712-0649
2007
McCammon, C.Longo, M., McCammon, C.Fe3+/Fe in lower mantle (Mg,Fe)O: calibration of the 'flank method'.Plates, Plumes, and Paradigms, 1p. abstract p. A594.MantlePerovskite
DS200712-0681
2007
McCammon, C.Marks, M.A.W., Rudnick, R.L., McCammon, C., Vennemann, T., Markl, G.Arrested kinetic Li isotope fractionation at the margin of the Ilimaussaq complex: evidence for open system processes during final cooling peralkaline igneous rocksChemical Geology, Vol. 246, 3-4, pp. 207-230.Europe, GreenlandGeochronology
DS200712-0777
2007
McCammon, C.Nestola, F., Longo, M., McCammon, C., Boffa Ballaran, T.Crystal structure refinement of Na bearing clinopyroxenes from mantle derived eclogite xenoliths.American Mineralogist, Vol. 92, pp. 1242-1245.RussiaDeposit - Udachnaya, Zagadochnaya
DS200812-0249
2009
McCammon, C.Creighton, S., Stachel, S., Matveev, S., Hofer, H., McCammon, C., Luth, R.W.Oxidation of the Kaapvaal lithospheric mantle driven by metasomatism.Contributions to Mineralogy and Petrology, Vol. 157, pp. 491-504.Africa, South AfricaMetasomatism, Kimberley
DS200812-0728
2008
McCammon, C.McCammon, C., Kantor, I., Narygina, O., Roquette, J., Ponkratz, Sergieev, Mezouar, Prakapenka, DubrovinskyStable intermediate spin ferrous iron in lower mantle perovskite.Nature Geoscience, Vol. 1, 10, pp. 684-687.MantlePerovskite
DS200912-0135
2009
McCammon, C.Creighton, S.,Stachel, T., Matveev, S., Hofer, H., McCammon, C., Luth, R.W.Oxidation of the Kaapvaal lithospheric mantle driven by metasomatism.Contributions to Mineralogy and Petrology, Vol. 157, 4, pp. 491-504.Africa, South AfricaMetasomatism
DS200912-0453
2008
McCammon, C.Longo, M., McCammon, C., Bulanova, G., Kaminsky, F.Iron oxidation state ( Mg.Fe)O calibration of the flank method on synthetic samples and application to natural inclusions in lower mantle diamonds.American Geological Union, Fall meeting Dec. 15-19, Eos Trans.Vol. 89, no.53, meeting supplement, 1p. abstractSouth America, Brazil, Mato GrossoPerovskite
DS201112-0955
2010
McCammon, C.Shiryaev, A.A., Zubavichus, Y.V., Veligzhanin, A.A., McCammon, C.Local environment and valence state of iron in Micro inclusions in fibrous diamonds: x-ray absorption and Mossbauer data.Russian Geology and Geophysics, Vol. 51, pp. 1262-1266.Africa, Democratic Republic of Congo, South America, BrazilDiamond morphology
DS201312-0720
2014
McCammon, C.Prescher, C., Weigel, C., McCammon, C., Narygina, O., Potapkin, V., Kupenko, I., Sinmyo, R., Chumakov, A.I., Dubrovinsky, L.Iron spin state in silicate glass at high pressure: implications for melts in the Earth's lower mantle.Earth and Planetary Science Letters, Vol. 385, pp. 130-136.MantleUHP
DS201412-0297
2014
McCammon, C.Glazyrin, K., Boffa Ballaran, T., Frost, D.J., McCammon, C., Kantor, A., Merlini, M., Hanfland, M., Dubrovinsky, L.Magnesium silicate perovskite and effect of iron oxidation state on its bulk sound velocity at the conditions of the lower mantle.Earth and Planetary Science Letters, Vol. 393, pp. 182-186.MantlePerovskite
DS201412-0480
2014
McCammon, C.Kressall, R.D., Fedortchouk, Y., McCammon, C., Elliott, B.Fe-Ti oxides in kimberlites: implications for kimberlites from the Ekati diamond mine, Northwest Territories.2014 Yellowknife Geoscience Forum Poster, p. 87, abstractCanada, Northwest TerritoriesDeposit - Ekati
DS201412-0565
2014
McCammon, C.McCammon, C.High pressure matters: the inside story of Earth's deep carbon cycle.EHPRG 2014, 1p. AbtstractMantleUHP
DS201412-0566
2013
McCammon, C.McCammon, C., Glazyrin, K., Kantor, A., Kantor, I., Kupenko, I., Narygina, O., Potapin, V., Vasily, P., Sinmyo, C., Chumakov, Ruffer, Sergueev, Smirnov, DubrovinskyIron spin state in silicate perovskite at conditions of Earth's deep interior.International Journal of High Pressure Research, Vol. 33, 3, pp. 663-672.MantlePerovskite
DS201412-0834
2014
McCammon, C.Sinmyo, R., Pesce, G., Greenberg, E., McCammon, C., Dubrovinsky, L.Lower mantle electrical conductivity based on measurements of Al, Fe-bearing perovskite under lower mantle conditions.Earth and Planetary Science Letters, Vol. 393, pp. 165-172.MantleGeophysics
DS201502-0088
2015
McCammon, C.Nimis, P., Goncharov, A., Ionov, D.A., McCammon, C.Fe3 partitioning systematics between orthopyroxene and garnet in mantle peridotite xenoliths and implications for thermobarometry of oxidized and reduced mantle rocks.Contributions to Mineralogy and Petrology, Vol. 169, 6p.MantlePeridotite
DS201608-1427
2016
McCammon, C.Nestola, F., Cerantola, V., Milani, S., Anzolini, C., McCammon, C., Novella, D., Kupenko, I., Chumakov, A., Ruffer, R., Harris, J.W.Synchrotron Mossbauer source technique for in situ measurement of iron-bearing inclusions in natural diamonds.Lithos, in press available, 6p.South America, BrazilDeposit - Juina

Abstract: We describe a new methodology to collect energy domain Mössbauer spectra of inclusions in natural diamonds using a Synchrotron Mössbauer Source (SMS). Measurements were carried out at the Nuclear Resonance beamline ID18 at the European Synchrotron Radiation Facility (Grenoble, France). We applied this non-destructive approach to collect SMS spectra of a ferropericlase inclusion still contained within its diamond host from Juina (Brazil). The high spatial resolution of the measurement (~ 15 ?m) enabled multiple regions of the 190 × 105 ?m2 inclusion to be sampled and showed that while Fe3 +/Fetot values in ferropericlase were below the detection limit (0.02) overall, there was a magnetic component whose abundance varied systematically across the inclusion. Hyperfine parameters of the magnetic component are consistent with magnesioferrite, and the absence of superparamagnetism allows the minimum particle size to be estimated as ~ 30 nm. Bulk Fe3 +/Fetot values are similar to those reported for other ferropericlase inclusions from Juina, and their variation across the inclusion can provide constraints on its history.
DS201705-0861
2017
McCammon, C.Nestola, F., Cerantola, V., Milani, S., Anzolini, C., McCammon, C., Novella, D., Kupenko, I., Chumakov, A., Rueffer, R., Harris, J.W.Synchroton Mossabauer source technique for in situ measurement of iron bearing inclusions in natural diamonds.European Geosciences Union General Assembly 2017, Vienna April 23-28, 1p. 16340 AbstractSouth America, BrazilDeposit - Juina

Abstract: We describe a new methodology to collect energy domain Mössbauer spectra of inclusions in natural diamonds using a Synchrotron Mössbauer Source (SMS). Measurements were carried out at the Nuclear Resonance beamline ID18 at the European Synchrotron Radiation Facility (Grenoble, France). We applied this non-destructive approach to collect SMS spectra of a ferropericlase inclusion still contained within its diamond host from Juina (Brazil). The high spatial resolution of the measurement (~ 15 ?m) enabled multiple regions of the 190 × 105 ?m2 inclusion to be sampled and showed that while Fe3 +/Fetot values in ferropericlase were below the detection limit (0.02) overall, there was a magnetic component whose abundance varied systematically across the inclusion. Hyperfine parameters of the magnetic component are consistent with magnesioferrite, and the absence of superparamagnetism allows the minimum particle size to be estimated as ~ 30 nm. Bulk Fe3 +/Fetot values are similar to those reported for other ferropericlase inclusions from Juina, and their variation across the inclusion can provide constraints on its history.
DS201707-1367
2017
McCammon, C.Sinmyo, R., McCammon, C., Dubrovinsky, L.The spin state of Fe3+ in lower mantle bridgmanite.American Mineralogist, Vol. 102, pp. 1263-1269.Mantlebridgmanite

Abstract: Iron- and aluminum-bearing MgSiO3 bridgmanite is the most abundant mineral in the Earth’s interior; hence its crystal chemistry is fundamental to expanding our knowledge of the deep Earth and its evolution. In this study, the valence and spin state of iron in well-characterized Al-free Fe3+-rich bridgmanite were investigated by means of Mössbauer spectroscopy to understand the effect of ferric iron on the spin state. We found that a minor amount of Fe3+ is in the low-spin state above 36 GPa and that its proportion does not increase substantially with pressure up to 83 GPa. This observation is consistent with recent experimental studies that used Mössbauer and X-ray emission spectroscopy. In the Earth’s deep lower mantle, Fe3+ spin crossover may take place at depths below 900 and 1200 km in pyrolite and MORB, respectively. However, the effect of spin crossover on physical properties may be small due to the limited amount of Fe3+ in the low-spin state.
DS201709-2014
2017
McCammon, C.Kiseeva, E.S., Vasiukov, D.M., Wood, B.J., McCammon, C., Stachel, T., Chumakov, A., Dubrovinsky, L.Oxidation state of majoritic garnet inclusions in diamond.Goldschmidt Conference, abstract 1p.Africa, South Africadeposit, Jagersfontein

Abstract: Diamond inclusions are the only samples from the mantle transition zone (410-660 km) and the lower mantle. Majoritic garnet is a rare inclusion, limited to pressures of ~8-20 Gpa with Si content being indicative of depth of re-equilibration. These garnet inclusions can therefore provide information on properties of the transition zone such as oxidation state. In this study, we used Synchrotron Mössbauer Source (SMS) to determine the ferric-ferrous ratios of 13 small (30 to 100 micrometers diameter) majoritic inclusions in diamonds from Jagersfontein. The studied inclusions have pyroxenitic affinities [1], with compositions intermediate between typical peridotite and eclogite. They contain 4.62-11.2 wt% CaO, 0.03-0.34 wt% Cr2O3 and Mg# of 0.65-0.81. Minimum pressures for their equilibration using Beyer and Frost [2] barometer are between 8 and 18 GPa with at least 4 of these inclusions being formed in the transition zone. The Fe3+/Fetotal ratios in the garnets increase from 0.08±0.01 to 0.30±0.03 with increasing pressure. These values define a clear extension of the trend apparent in the data from peridotite xenoliths crystallised at lower pressures. Thermodynamic calculations suggest that these high ferric contents correspond to oxygen fugacities above the FeFeO (IW) buffer, which means that the high Fe3+ contents were not generated by disproportionation of Fe2+ to Fe3+ and Fe0 . It is more likely that carbonate was the oxidising agent responsible for generating the high Fe3+ of these garnets.
DS201710-2219
2017
McCammon, C.Cerantola, V., Bykova, E., Kupenko, I., Merlini, M., Ismailova, L., McCammon, C., Bykov, M., Chumakov, A.I., Petitgirard, S., Kantor, I., Svityk, V., Jacobs, J., Hanfland, M., Mezouar, M., Prescher, C., Ruffer, R., Prakapenka, V.B., Duvbovinsky, L.How iron carbonates help form diamonds.Nature Communications, July 18 #15960Mantlecarbonate inclusions
DS201807-1491
2018
McCammon, C.Garber, J.M., Maurya, S., Hernandez, J-A., Duncan, M.S., Zeng, Li., Zhang, H.L., Faul, U., McCammon, C., Montagner, J-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L.Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere. Mentions Jericho and Roberts VictorGeochemistry, Geophysics, Geosystems, https://doi.org/10.1029/2018GCC007534Globalthermobarometry

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120?150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS201808-1744
2018
McCammon, C.Fu, S., Yang, J., Zhang, Y., Okuschi, T., McCammon, C., Kim, H-I., Lee, S.K., Lin, J-F.Abnormal elasticity of Fe bearing bridgmanite in the Earth's lower mantle.Geophysical Research Letters, Vol. 45, 10, pp. 4725-4732.Mantlebridgmanite

Abstract: Seismic heterogeneities in the Earth's lower mantle have been attributed to thermal and/or chemical variations of constituent minerals. Bridgmanite is the most abundant lower?mantle mineral and contains Fe and Al in its structure. Knowing the effect of Fe on compressional and shear wave velocities (VP, VS) and density of bridgmanite at relevant pressure?temperature conditions can help to understand seismic heterogeneities in the region. However, experimental studies on both VP and VS of Fe?bearing bridgmanite have been limited to pressures below 40 GPa. In this study, VP and VS of Fe?bearing bridgmanite were measured up to 70 GPa in the diamond anvil cell. We observed drastic softening of VP by ~6(±1)% at 42.6-58 GPa and increased VS at pressures above 40 GPa. We interpret these observations as due to a spin transition of Fe3+. These observations are different to previous views on the effect of Fe on seismic velocities of bridgmanite. We propose that the abnormal sound velocities of Fe?bearing bridgmanite could help to explain the seismically observed low correlation between VP and VS in the mid?lower mantle. Our results challenge existing models of Fe enrichment to explain the origin of Large Low Shear Velocity provinces in the lowermost mantle.
DS201808-1745
2018
McCammon, C.Garber, J.M., Maurya, S., Hernandez, J-A., Duncan, M.S., Zeng, L., Zhang, H.L., Faul, U., McCammon, C., Montagner, J-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L.Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.G3 Geochemistry, Geophysics, Geosystems, http:/orchid.org/0000-0001-5313-0982Mantleeclogite
DS201809-2020
2018
McCammon, C.Fedortchouk, Y., Chinn, I., Liebske, C., McCammon, C.Mantle metasomatism as recorded in diamond dissolution features.Goldschmidt Conference, 1p. AbstractAfrica, Botswanadeposit - Orapa

Abstract: Roots of continental cratons keep a long record of multiple metasomatic events, but their trace is complicated due to the mixed signals left by these events in the composition of mantle silicate minerals. Simple composition helps diamonds to provide a more robust record of the latest metasomatic events which they witnessed. Growth and dissolution features on the diamond surface are sensitive to the composition of the reacting media. In this study we use mantle-derived resorption features on natural diamonds to examine the nature of metasomatic events in diamondiferous mantle lithologies. We use experiments at mantle conditions to examine how the composition of fluids and melts affect diamond resorption. We then compare these results to the features of natural diamonds to determine which of the tested compositions could have acted as metasomatic agents in Earth’s cratonic roots. Diamond dissolution experiments conducted at 6 GPa, 1200 - 1500oC using synthetic MgO-CaO-SiO2-CO2-H2O system examined the effect of CHO fluid, silica-saturated CHO fluid, aqueous and “dry” silica-carbonate and carbonate melts. Results show that the main control of diamond resorption morphology is the state of the reacting media: fluid vs. melt. We compared the experimental results to diamonds with mantle-derived resorption features from two kimberlites from the Orapa kimberlite cluster (Botswana). We identified twelve mantle-derived resorption types, none of which resembled the products of resorption in fluids. Most of the observed resorption types could be produced by dissolution in mantle melts with variable proportions of carbonate and silicate components and in the range of temperatures. The most abundant resorption type resembles the product of diamond dissolution in carbonate melts at temperatures above 1450oC. Our results suggest that fluid-metasomatism is not destructive for diamonds while melt-metasomatism is. The lower hydrous carbonated solidus of lherzolite compared to harzburgite can result in the shift the process from diamond growth in fluids to diamond dissolution in melts due to metasomatic transformation of harzburgite into lherzolite.
DS201809-2083
2018
McCammon, C.Schulze, K., Marquardt, H., Kawazoe, T., Boallaran, T.B., McCammon, C., Koch-Muller, M., Kurnosov, A., Marquardt, K.Seismically invisable water in Earth's transition zone?Earth and Planetary Science Letters, Vol. 498, pp. 9-16.Mantlewater

Abstract: Ringwoodite, the dominant mineral at depths between 520 km and 660 km, can store up to 2-3 wt.% of water in its crystal structure, making the Earth's transition zone a plausible water reservoir that plays a central role in Earth's deep water cycle. Experiments show that hydration of ringwoodite significantly reduces elastic wave velocities at room pressure, but the effect of pressure remains poorly constrained. Here, a novel experimental setup enables a direct quantification of the effect of hydration on ringwoodite single-crystal elasticity and density at pressures of the Earth's transition zone and high temperatures. Our data show that the hydration-induced reduction of seismic velocities almost vanishes at conditions of the transition zone. Seismic data thus agree with a wide range of water contents in the transition zone.
DS201901-0032
2018
McCammon, C.Fedortchouk, Y., Liebske, C., McCammon, C.Diamond destruction and growth during mantle metasomatism: an experimental study of diamond resorption features.Earth and Planetary Science Letters, Vol. 506, pp. 493-506.Mantlemetasomatism

Abstract: Most diamonds found in kimberlites show complex patterns of growth and dissolution (resorption) surface features. Populations of diamonds from within single kimberlite bodies commonly contain a large diversity of diamond surface forms, some of which are a result of dissolution in kimberlite magma and others are inherited from the mantle. Morphological studies of natural diamonds differentiated features produced during dissolution in kimberlite magma and during mantle metasomatism. The former features were experimentally reproduced at 1 3 GPa and used to infer the presence and composition of magmatic fluid in different kimberlites. However, the mantle-derived resorption features have not been reproduced experimentally and the composition and origins of their formative solvents are unknown. Here we report the results of diamond dissolution experiments conducted in a multi-anvil apparatus at 6 GPa and 1200 to 1500 °C in synthetic CaO MgO SiO2 CO2 H2O system. The experiments produced very different diamond resorption morphologies in COH fluid, in silicate-saturated fluid, and in silicate and carbonate melts. Dissolution in SiO2-free COH fluid developed rounded crystal forms with shallow negative trigons, striations and hillocks, which are commonly observed on natural diamonds and are similar in 6 GPa and in 1 3 GPa experiments. However, silicate-saturated fluid produced very different resorption features that are rarely observed on natural diamonds. This result confirms that natural, SiO2-poor fluid-induced resorption develops under the comparatively low-pressures of kimberlite ascent, because at mantle pressures the high content of SiO2 in fluids would produce features like those from the silicate-saturated experiments. Comparison of the experimental products from this study to natural diamond resorption features from the literature suggests that natural diamonds show no record of dissolution by fluids during mantle metasomatism. Diamond resorption morphologies developed in experiments with silicate carbonate melts closely resemble many of the mantle-derived resorption features of natural diamonds, whose diversity can result from variable SiO2 concentration in carbonatitic melts and temperature variation. The experimental results imply that metasomatism by fluids does not dissolve diamond, whereas metasomatism by melts is diamond-destructive. The repetitive growth-dissolution patterns of natural diamonds could be due to diamond growth from fluids in harzburgitic lithologies followed by its dissolution in partial melts.
DS201902-0285
2018
McCammon, C.Kiseeva, E.S., Vasiukov, D.M., Wood, B.J., McCammon, C., Stachel, T., Bykov, M., Bykova, E., Chumakov, A., Cerantola, V., Harris, J.W., Dubrovinsky, L.Oxidized iron in garnets from the mantle transition zone.Nature Geoscience, Vol. 11, pp. 144-147. Africa, South Africadeposit - Jagersfontein

Abstract: The oxidation state of iron in Earth’s mantle is well known to depths of approximately 200?km, but has not been characterized in samples from the lowermost upper mantle (200-410?km depth) or the transition zone (410-660?km depth). Natural samples from the deep (>200?km) mantle are extremely rare, and are usually only found as inclusions in diamonds. Here we use synchrotron Mössbauer source spectroscopy complemented by single-crystal X-ray diffraction to measure the oxidation state of Fe in inclusions of ultra-high pressure majoritic garnet in diamond. The garnets show a pronounced increase in oxidation state with depth, with Fe3+/(Fe3++ Fe2+) increasing from 0.08 at approximately 240?km depth to 0.30 at approximately 500?km depth. The latter majorites, which come from pyroxenitic bulk compositions, are twice as rich in Fe3+ as the most oxidized garnets from the shallow mantle. Corresponding oxygen fugacities are above the upper stability limit of Fe metal. This implies that the increase in oxidation state is unconnected to disproportionation of Fe2+ to Fe3+ plus Fe0. Instead, the Fe3+ increase with depth is consistent with the hypothesis that carbonated fluids or melts are the oxidizing agents responsible for the high Fe3+ contents of the inclusions.
DS201907-1555
2019
McCammon, C.Kupenko, G.A., Vasilukov, D.M., McCammon, C., Charleton, S., Cerantola, V., Kantor, I., Chumakov, A.I.., Ruffer, R., Dubrovinsky, L, Sanchez-Valle, C.Magnetism in cold subducting slabs at mantle transition zone depths.Nature, Vol. 570, 7759, p. 102.Mantlesubduction

Abstract: The Earth’s crust-mantle boundary, the Mohorovi?i? discontinuity, has been traditionally considered to be the interface between the magnetic crust and the non-magnetic mantle1. However, this assumption has been questioned by geophysical observations2,3 and by the identification of magnetic remanence in mantle xenoliths4, which suggest mantle magnetic sources. Owing to their high critical temperatures, iron oxides are the only potential sources of magnetic anomalies at mantle depths5. Haematite (?-Fe2O3) is the dominant iron oxide in subducted lithologies at depths of 300 to 600 kilometres, delineated by the thermal decomposition of magnetite and the crystallization of a high-pressure magnetite phase deeper than about 600 kilometres6. The lack of data on the magnetic properties of haematite at relevant pressure-temperature conditions, however, hinders the identification of magnetic boundaries within the mantle and their contribution to observed magnetic anomalies. Here we apply synchrotron Mössbauer source spectroscopy in laser-heated diamond anvil cells to investigate the magnetic transitions and critical temperatures in Fe2O3 polymorphs7 at pressures and temperatures of up to 90 gigapascals and 1,300 kelvin, respectively. Our results show that haematite remains magnetic at the depth of the transition zone in the Earth’s mantle in cold or very cold subduction geotherms, forming a frame of deep magnetized rocks in the West Pacific region. The deep magnetic sources spatially correlate with preferred paths of the Earth’s virtual geomagnetic poles during reversals8 that might not reflect the geometry of the transitional field. Rather, the paths might be an artefact caused by magnetized haematite-bearing rocks in cold subducting slabs at mid-transition zone depths. Such deep sources should be taken into account when carrying out inversions of the Earth’s geomagnetic data9, and especially in studies of planetary bodies that no longer have a dynamo10, such as Mars.
DS201911-2537
2019
McCammon, C.Kiseeva, E.S., Wood, B.J., McCammon, C., Ashchepkov, I.Ferric ferrous ratios in mantle xenoliths by synchrotron mossbauer source spectroscopy. Kilbourne HoleGoldschmidt2019, 1p. AbstractUnited States, Californiaspectroscopy

Abstract: Synchrotron Mössbauer Source (SMS) spectroscopy (ESRF, Grenoble, France) has high spatial resolution (~20 microns) and has been successfully applied to measuring Fe3+ concentrations in diamond inclusions [1,2]. Over the last few decades a number of studies have been conducted on individual minerals from mantle xenoliths in order to determine the oxidation state of the upper mantle [3,4]. These studies were conducted using ?50 mg of handpicked grains as opposed to individual crystals. In this study, we applied SMS to measure ferric iron contents of individual spinels, orthopyroxenes, clinopyroxenes and garnets from 5 spinel peridotite xenoliths and 1 pyroxenite and 2 eclogite xenoliths. Spinel xenoliths derive from Kilbourne hole, Mont Briançon and Ichinomegata. Spinels from these xenoliths were previously analysed by Mössbauer spectroscopy on bulk separates [4]. Eclogite xenoliths (UAS 1055, UAS 1525) and pyroxenite xenolith (UAS 510) were obtained from Udachnaya kimberlite pipe in Siberia. In spinel peridotites measured ratios range between 0.04- 0.14 Fe3+/Fetot for Opx, 0.14-0.19 Fe3+/Fetot for Cpx and between 0.15-0.23 for Spl. These values are broadly in agreement with previous measurements [3]. In eclogites and pyroxenite, the ratios range between 0.05-0.16 for garnet and 0.07-0.17 for Cpx, showing DGrt/Cpx for Fe3+ of 0.8-1.9. Oxygen fugacities derived from the spinel-olivineorthopyroxene oxybarometer are consistent with previous results for the continental lithosphere fO2 of between -1 and +1 log units relative to the FMQ buffer [5]. Nevertheless we observe small differences between our results on individual grains and previous data on bulk separates.
DS202002-0206
2020
McCammon, C.McCammon, C., Bureau, H., Cleaves II, H.J., Cottrell, E., Dorfman, S.M., Kellogg, L.H., Li, J., Mikhail, S., Moussallam, Y., Sanloup, C., Thomson, A.R., Brovarone, A.V.Deep Earth carbon reactions through time and space. ( mentions diamond)American Mineralogist, Vol. 105, pp. 22-27.Mantlesubduction

Abstract: Reactions involving carbon in the deep Earth have limited manifestations on Earth's surface, yet they have played a critical role in the evolution of our planet. The metal-silicate partitioning reaction promoted carbon capture during Earth's accretion and may have sequestered substantial carbon in Earth's core. The freezing reaction involving iron-carbon liquid could have contributed to the growth of Earth's inner core and the geodynamo. The redox melting/freezing reaction largely controls the movement of carbon in the modern mantle, and reactions between carbonates and silicates in the deep mantle also promote carbon mobility. The 10-year activity of the Deep Carbon Observatory has made important contributions to our knowledge of how these reactions are involved in the cycling of carbon throughout our planet, both past and present, and has helped to identify gaps in our understanding that motivate and give direction to future studies.
DS202109-1454
2021
McCammon, C.Bindi, L., Sinmyo, R., Bykova, E., Ovsyannikov, S.V., McCammon, C., Kupenko, I., Ismailova, L., Dubrovinsky, L., Xie, X.Discovery of Elgoresyite ( Mg,FE)5Si2O9: implications for novel iron magnesium silicates in rocky planetery interiors. Mentions Earth's magmatismACS Earth Space Chemistry, Vol. 5, pp. 2124-2130.Mantlebridgmanite

Abstract: As the most abundant material of rocky planets, high-pressure polymorphs of iron- and aluminum-bearing magnesium silicates have long been sought by both observations and experiments. Meanwhile, it was recently revealed that iron oxides form (FeO)m(Fe2O3)n homologous series above ?10 GPa according to laboratory high-pressure experiments. Here, we report a new high-pressure iron-magnesium silicate, recently approved by the International Mineralogical Association as a new mineral (No. 2020-086) and named elgoresyite, in a shock-induced melt vein of the Suizhou L6 chondrite with a chemistry of (Mg,Fe)5Si2O9. The crystal structure of this new silicate is the same as the iron oxide Fe7O9, strongly suggesting that silicates also form ((Mg,Fe)O)m + n(SiO2)n series that are isostructural to iron oxides via (Mg2+,Fe2+) + Si4+ = 2Fe3+ substitution. To test this hypothesis, the phase relationships of the silicates and iron oxides should be further investigated at higher temperature conditions. Newly found iron-magnesium silicate is a potential constituent mineral in rocky planets with relatively high MgO + FeO content.
DS202110-1623
2021
McCammon, C.Liu, Z., Fei, H., Chen, L., McCammon, C., Katsura, T.Bridgemanite is nearly dry at the top of the lower mantle.Earth and Planetary Science Letters, Vol. 570, 117088Mantlebridgemanite

Abstract: Water solubility in the dominant lower-mantle bridgmanite phase remains controversial. Discrepancies between previous results highlight the importance of the growth high-quality single crystals of bridgmanite under high-pressure and high-temperature conditions corresponding to the top of the lower mantle. Here we synthesized high-quality single crystals of aluminous bridgmanite up to 300 ?m in size that were saturated with hydrous melt at 24-26 GPa and 1700-1900 K using both stoichiometric and MgO-rich non-stoichiometric hydrous starting materials in a multi-anvil press. Fourier-transform infrared spectroscopy measurements on clear and pure spots of the single-crystal bridgmanites did not detect any pronounced OH-stretching bands, which were prominent in some earlier studies. The present results support that the lower-mantle dominated bridgmanite is nearly dry, at least at the top of the lower mantle, and that Al3+ and Fe3+ cannot enhance water incorporation into the crystal structure even in the presence of oxygen vacancies. Large partition coefficients of water between transition-zone minerals and dry lower-mantle dominated bridgmanite further support dehydration melting at the top of the lower mantle. We suggest that the majority of the top of a pyrolitic lower mantle is nearly dry based on the dry principal minerals and stability of hydrous phases in this region.
DS1995-1191
1995
McCammon, C.A.McCammon, C.A., Chinn, I.L., Gurney, J.J., McCallum, M.E.Determination of the ferric iron content of diamond inclusions from George Creek - Mossbauer spectroscopyProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 359-361.WyomingDiamond inclusions, Deposit -George Creek
DS1995-1192
1995
McCammon, C.A.McCammon, C.A., Griffin, W.L., Shee, S.H., O'Neill, H. St.Determination of ferric iron variation within zoned garnets from the Wesselton kimberlite using Mossbauer.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 362-364.South AfricaSpectroscopy, Deposit -Wesselton
DS1995-1193
1995
McCammon, C.A.McCammon, C.A., Shee, S.H., O'Neill, H.Determination of iron variation within zoned garnets from the Wesselton kimberlite using a Mossbauer Milliprobe.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Annual Meeting Abstracts, Vol. 20, p. A67 AbstractSouth AfricaGeochemistry -garnets, Deposit -Wesselton
DS1998-0970
1998
McCammon, C.A.McCammon, C.A.Methods for determination of Fe3 iron in microscopic samples7th International Kimberlite Conference Abstract, pp. 555-7.GlobalSpectroscopy - oxygen fugacity, diamond inclusions, Petrology - experimental
DS1998-0971
1998
McCammon, C.A.McCammon, C.A., Chinn, I.L., McCallum, M.E.Ferric iron content of mineral inclusions in diamonds from George Creek determined - Mossbauer spectroscopy.Contributions to Mineralogy and Petrology, Vol. 133, No. 1-2, pp. 30-37.ColoradoMineral inclusions, Deposit - George Creek
DS1999-0451
1999
McCammon, C.A.McCammon, C.A.Methods for determination of iron/iron (Fe/Fe) in microscopic samples7th International Kimberlite Conference Nixon, Vol. 2, pp. 540-44.GlobalPetrology, Mineral chemistry
DS2001-0746
2001
McCammon, C.A.McCammon, C.A., Griffin, W.L., Shee, S.R., O'Neill, H.R.Oxidation during metasomatism in ultramafic xenoliths from Wesselton kimberlite: implications for survival..Contributions to Mineralogy and Petrology, Vol. 141, No. 3, June, pp. 287-296.South AfricaXenoliths, diamond survival, Deposit - Wesselton
DS2002-1024
2002
McCammon, C.A.McCammon, C.A.From diamonds to defects: new ideas about the Earth's interiorHyperfine Interactions, Vol. 141/142, No. 1/4, pp. 73-81 Ingenta 1025292115MantleGeochemistry
DS2002-1025
2002
McCammon, C.A.McCammon, C.A., Beccero, A.I., Lauterbach, S., Blass, U., Marion, S.Oxygen vacancies in perovskite and related structures: implications for the lower mantle.Materials Research Society Symposium Proceedings, Vol. 718, pp. 109-114. Ingenta 1025440383MantlePerovskite
DS2003-0898
2003
McCammon, C.A.McCammon, C.A., Kopylova, M.G.Mantle oxygen fugacity and diamond formation8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, AbstractMantleMantle petrology, Diamond - redox
DS200412-0585
2004
McCammon, C.A.Frost, D.J., Liebske, C., Langenhorst, F., McCammon, C.A., Tronnes, R.G., Rubie, D.C.Experimental evidence for the existence of iron rich metal in the Earth's lower mantle.Nature, No. 6981, March 25, pp. 409-411.MantleSulphides
DS200412-0586
2004
McCammon, C.A.Frost, D.J., Liebske, C., McCammon, C.A., Langenhorst, F., Tronnes, R., Rubie,D.C.Experimental evidence for the existence of a metallic iron rich phase in the Earth's mantle.Lithos, ABSTRACTS only, Vol. 73, p. S38. abstractMantleRedox conditions
DS200412-1257
2003
McCammon, C.A.McCammon, C.A., Kopylova, M.G.Mantle oxygen fugacity and diamond formation.8 IKC Program, Session 6, AbstractMantleMantle petrology Diamond - redox
DS200412-1258
2004
McCammon, C.A.McCammon, C.A., Lauterbach, S., Seifert, F., Langenhorst, F., Van Aken, P.A.Iron oxidation state in lower mantle mineral assemblages. Part 2.Earth and Planetary Science Letters, Vol. 222, 2, pp. 435-449.MantleMineral chemistry
DS200412-1259
2004
McCammon, C.A.McCammon, C.A., Stachel, T., Harris, J.W.Iron oxidation state in lower mantle mineral assemblages. Part 1.Earth and Planetary Science Letters, Vol. 222, 2, pp. 423-434.MantleMineral chemistry
DS200412-1863
2003
McCammon, C.A.Smyth, J.R., Holl, C.M., Frost, D.J., Jacobsen, S.D., Langenhorst, F., McCammon, C.A.Structural systematics of hydrous ring woodite and water in Earth's interior.American Mineralogist, Vol. 88, 10, Oct. pp. 1402-7.MantleMineralogy
DS200412-2117
2004
McCammon, C.A.Williams, H.M., McCammon, C.A., Peslier, A.H., Halliday, A.N., Teutsch, N., Levasseur, S., Burg, J-P.Iron isotope fractionation and the oxygen fugacity of the mantle.Science, Vol. 304, 5677, June 11, p. 1656.MantleGeothermobarometry
DS200412-2118
2004
McCammon, C.A.Williams, H.M., McCammon, C.A., Peslier, Halliday, Teutsch, Levasseur, BurgIron isotope fractionation and the oxygen fugacity of the mantle.Geochimica et Cosmochimica Acta, 13th Goldschmidt Conference held Copenhagen Denmark, Vol. 68, 11 Supp. July, ABSTRACT p.A563.MantleMelting
DS200512-0151
2005
McCammon, C.A.Chakhmouradian, A.R., McCammon, C.A., MacBride, L., Cahill, C.L.Titaniferous garnets in carbonatites: their significance and place in the evolutionary history of host rocks.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Classification - mineralogy
DS200612-0885
2005
McCammon, C.A.McCammon, C.A.Mantle oxidation state and oxygen fugacity: constraints on mantle chemistry, structure and dynamics.American Geophysical Union, Geophysical Monograph, Ed. Van der Hilst, Earth's Deep Mantle, structure ...., No. 160, pp. 219-240..MantleGeochemistry
DS200612-1174
2006
McCammon, C.A.Romano, C., Poe, B.T., Kreidie, N., McCammon, C.A.Electrical conductivities of pyrope almandine garnets up to 19 GPa and 1700 C.American Mineralogist, Vol. 91, 9, pp. 1371-1377.MantleDiscontinuity
DS200712-0090
2006
McCammon, C.A.Bolfan Casanova, N., McCammon, C.A., Mackwell, S.J.Water in transition zone and lower mantle minerals.American Geophysical Union, Geophysical Monograph, No. 168, pp. 57-68.MantleWater
DS200712-1157
2007
McCammon, C.A.Williams, H.M., Nielsen, S.G., Renac, C., McCammon, C.A., Griffin, W.L., O'Reilly, S.Y.Fractionation of Fe and O isotopes in the mantle: implications for the origins of eclogites and the source regions of mantle plumes.Plates, Plumes, and Paradigms, 1p. abstract p. A1118.MantleSubduction
DS200812-0371
2008
McCammon, C.A.Frost, D.J., McCammon, C.A.The redox state of Earth's mantle.Annual Review of Earth and Planetary Sciences, Vol. 36, May, pp. 389-420.MantleRedox
DS200912-0232
2009
McCammon, C.A.Frost, D.J., McCammon, C.A.The effect of oxygen fugacity on the olivine to wadsleyite transformation: implications for remote sensing of mantle redox state at the 410 km seismic ...American Mineralogist, Vol. 94, 7, pp. 872-882.MantleUHP - discontinuity
DS201012-0643
2010
McCammon, C.A.Ruskov, T., Spirov, I., Georgieva, M., Yamamoto, S., Green, H.W., McCammon, C.A., Dobrzhinetskaya, L.F.Mossbauer spectroscopy studies of the valence state of iron in chromite from the Luobusa Massif of Tibet: implications for a highly reduced mantle.Journal of Metamorphic Geology, Vol. 28, 5, pp. 551-560.Asia, TibetMetasomatism
DS201112-0729
2011
McCammon, C.A.Naygina, O., Dubrovinsky, L.S., McCammon, C.A., Kurnosov, A., Kantor, I.Y., Prakapenka, V.B., Dubrovinskaia, N.A.X-ray diffraction and Mossbauer spectroscopy study of fcc iron hydride FeH at high pressures and implications for the composition of the Earth's core.Earth and Planetary Science Letters, Vol. 307, 3-4, pp. 409-414.MantleHydrogen budget
DS201112-0996
2011
McCammon, C.A.Stagno, V., McCammon, C.A., Frost, D.J.High pressure calibration of the oxygen fugacity recorded by garnet bearing peridotites.Goldschmidt Conference 2011, abstract p.1928.MantleGraphite/diamond in peridotite mantle
DS201212-0701
2012
McCammon, C.A.Stagno, V., Fei, Y., McCammon, C.A., Frost, D.J.Redox equilibration temperatures within eclogite assemblages as function of pressure and temperature: implications for the deep carbon cycle.emc2012 @ uni-frankfurt.de, 1p. AbstractMantleRedox
DS201312-0147
2013
McCammon, C.A.Chang, Y-Y., Jacobsen, S.D., Lin, J-F., Bina, C.R., Thomas, S-M., Wu, J., Shen, G., Xiao, Y., Chow, P., Frost, D.J., McCammon, C.A., Dera, P.Spin transition off F23+ in Al bearing phase D: an alternative explanation for small scale seismic scatterers in the mid-lower mantle.Earth and Planetary Science Letters, Vol. 382, pp. 1-9.MantleGeophysics, seismics
DS201312-0282
2013
McCammon, C.A.Frost, D.J., Stagno, V., McCammon, C.A., Fei, Y.The stability of carbonate melt in eclogite rocks with respect to oxygen fugacity. Diamond formation.Goldschmidt 2013, AbstractMantleRedox
DS201503-0179
2015
McCammon, C.A.Stagno, V., Frost, D.J., McCammon, C.A., Mohseni, H., Fei, Y.The oxygen fugacity at which graphite or diamond forms from carbonate bearing melts in eclogitic rocks.Contributions to Mineralogy and Petrology, Vol. 169, 18p.TechnologyRedox, carbonatite, geobarometry
DS201504-0204
2015
McCammon, C.A.Kaminsky, F.V., Ryabchikov, I.D., McCammon, C.A., Longo, M., Abakumov, A.M., Turner, S., Heidari, H.Oxidation potential in the Earth's lower mantle as recorded by ferropericlase inclusions in diamond.Earth and Planetary Science Letters, Vol. 417, pp. 49-56.South America, BrazilDeposit - Juina
DS201510-1785
2015
McCammon, C.A.Martin, A.P., Price, R.C., Cooper, A.F., McCammon, C.A.Petrogenesis of the rifted southern Victoria Land lithospheric mantle, Antarctica, inferred from petrography, geochemistry, thermobarometry and oxybarometry of peridotite and pyroxenite xenoliths from the Mount Morning eruptive centre.Journal of Petrology, Vol. 56, 1, pp. 193-226.AntarcticaMelting, subduction

Abstract: The lithospheric mantle beneath West Antarctica has been characterized using petrology, whole-rock and mineral major element geochemistry, whole-rock trace element chemistry and Mössbauer spectroscopy data obtained on a suite of peridotite (lherzolite and harzburgite) and pyroxenite xenoliths from the Mount Morning eruptive centre, Southern Victoria Land. The timing of pyroxenite formation in Victoria Land overlaps with subduction of the Palaeo-Pacific plate beneath the Gondwana margin and pyroxenite is likely to have formed when fluids derived from, or modified by, melting of the subducting, eclogitic, oceanic crustal plate percolated through peridotite of the lithospheric mantle. Subsequent melting of lithospheric pyroxenite veins similar to those represented in the Mount Morning xenolith suite has contributed to the enriched trace element (and isotope) signatures seen in Cenozoic volcanic rocks from Mount Morning, elsewhere in Victoria Land and Zealandia. In general, the harzburgite xenoliths reflect between 20 and 30% melt depletion. Their depleted element budgets are consistent with Archaean cratonization ages and they have mantle-normalized trace element patterns comparable with typical subcontinental lithospheric mantle. The spinel lherzolite mineral data suggest a similar amount of depletion to that recorded in the harzburgites (20-30%), whereas plagioclase lherzolite mineral data suggest <15% melt depletion. The lherzolite (spinel and plagioclase) xenolith whole-rocks have compositions indicating <20% melt depletion, consistent with Proterozoic to Phanerozoic cratonization ages, and have mantle-normalized trace element patterns comparable with typical depleted mid-ocean ridge mantle. All peridotite xenoliths have undergone a number of melt-rock reaction events. Melting took place mainly in the spinel peridotite stability field, but one plagioclase peridotite group containing high-sodium clinopyroxenes is best modelled by melting in the garnet field. Median oxygen fugacity estimates based on Mössbauer spectroscopy measurements of spinel and pyroxene for spinel-facies conditions in the rifted Antarctic lithosphere are -0·6 ?log fO2 at Mount Morning and –1·0 ± 0·1 (1?) ?log fO2 for all of Victoria Land, relative to the fayalite-magnetite-quartz buffer. These values are in good agreement with a calculated global median value of -0·9 ± 0·1 (1?) ?log fO2 for mantle spinel-facies rocks from continental rift systems.
DS201603-0368
2015
McCammon, C.A.Chang, Y-Y., Jacobsen, S.D., Bina, C.R., Thomas, S-M., Smyth, J.R., Frost, D.J., Boffa Ballaran, T., McCammon, C.A., Hauri, E.H., Inoue, T., Yurimoto, H., Meng, Y., Dera, P.Comparative compressibility of hydrous wadsleyite and ringwoodite: effect of H2O and implications for detecting water in the transition zone.Journal of Geophysical Research,, Vol. 120, 12, pp. 8259-8280.MantleRingwoodite

Abstract: Review of recent mineral physics literature shows consistent trends for the influence of Fe and H2O on the bulk modulus (K0) of wadsleyite and ringwoodite, the major phases of Earth's mantle transition zone (410-660?km). However, there is little consensus on the first pressure derivative, K0??=?(dK/dP)P=0, which ranges from about 4 to >5 across experimental studies and compositions. Here we demonstrate the importance of K0? in evaluating the bulk sound velocity of the transition zone in terms of water content and provide new constraints on the effect of H2O on K0? for wadsleyite and ringwoodite by conducting a comparative compressibility study. In the experiment, multiple crystals of hydrous Fo90 wadsleyite containing 2.0 and 0.25?wt?% H2O were loaded into the same diamond anvil cell, along with hydrous ringwoodite containing 1.4?wt?% H2O. By measuring their pressure-volume evolution simultaneously up to 32?GPa, we constrain the difference in K0? independent of the pressure scale, finding that H2O has no effect on K0?, whereas the effect of H2O on K0 is significant. The fitted K0? values of hydrous wadsleyite (0.25 and 2.0?wt?% H2O) and hydrous ringwoodite (1.4?wt?% H2O) examined in this study were found to be identical within uncertainty, with K0? ~3.7(2). New secondary-ion mass spectrometry measurements of the H2O content of these and previously investigated wadsleyite samples shows the bulk modulus of wadsleyite is reduced by 7.0(5)?GPa/wt?% H2O, independent of Fe content for upper mantle compositions. Because K0? is unaffected by H2O, the reduction of bulk sound velocity in very hydrous regions of transition zone is expected to be on the order of 1.6%, which is potentially detectible in high-resolution, regional seismology studies.
DS201608-1430
2016
McCammon, C.A.Palot, M., Jacobsen, S.D., Townsend, J.P., Nestols, F., Marquardt, K., Harris, J.W., Stachel, T., McCammon, C.A., Pearson, D.G.Evidence for H2O bearing fluids in the lower mantle from diamond inclusion.Lithos, in press available 27p.South America, BrazilSao Luis

Abstract: In this study, we report the first direct evidence for water-bearing fluids in the uppermost lower mantle from natural ferropericlase crystal contained within a diamond from São Luíz, Brazil. The ferropericlase exhibits exsolution of magnesioferrite, which places the origin of this assemblage in the uppermost part of the lower mantle. The presence of brucite-Mg(OH)2 precipitates in the ferropericlase crystal reflects the later-stage quenching of H2O-bearing fluid likely in the transition zone, which has been trapped during the inclusion process in the lower mantle. Dehydration melting may be one of the key processes involved in transporting water across the boundary between the upper and lower mantle.
DS201702-0226
2016
McCammon, C.A.Martin, R.F., Alarie, E., Minarik, W.G., Waczek, Z., McCammon, C.A.Titanium rich magneso-hastingite macrocrysts in a camptonite dike, Lafarge quarry, Montreal Island, Quebec: early crystallization in a pseudo-unary system.The Canadian Mineralogist, Vol. 54, pp. 65-78.Canada, QuebecCamptonite

Abstract: A prominent dike of camptonite cuts the Middle Ordovician Tétreauville Formation of the Trenton Group in the Montréal-Est quarry operated by Lafarge Canada Inc. The “Lafarge” dike is strikingly porphyritic, with largely anhedral macrocrysts of unzoned calcic amphibole up to 13 cm across. The macrocrysts are rimmed with ferri-kaersutite resembling the amphibole in the fine-grained matrix of the camptonite. The magnesio-hastingstite macrocrysts have virtually the same composition as the matrix; they thus grew without much of a boundary layer. The magma crystallized in a disequilibrium way as a pseudo-unary system. The macrocrysts are unusually enriched in Fe3+ (approximately 44% of the total iron), yet locally enclose globules of immiscible sulfide melt. The magma became oxygenated owing to preferential loss of hydrogen upon the dissociation of aqueous gas bubbles. The amygdaloidal macrocrysts have a relatively high ?D value because of this loss of H2; the values of ?18O are typical of an upper mantle source. Camptonite dikes are very common on Mont Royal. Like the Lafarge dike, they likely arose by the disequilibrium crystallization of batches of the parental melt of asthenospheric origin.
DS201910-2243
2019
McCammon, C.A.Amrstrong, K., Frost, D.J., McCammon, C.A., Rubie, D.C., Boffa Ballaran, T.Deep magma ocean formation set the oxidation state of Earth's mantle.Science, Vol. 365, 6456, pp. 903-906.Mantleredox

Abstract: The composition of Earth’s atmosphere depends on the redox state of the mantle, which became more oxidizing at some stage after Earth’s core started to form. Through high-pressure experiments, we found that Fe2+ in a deep magma ocean would disproportionate to Fe3+ plus metallic iron at high pressures. The separation of this metallic iron to the core raised the oxidation state of the upper mantle, changing the chemistry of degassing volatiles that formed the atmosphere to more oxidized species. Additionally, the resulting gradient in redox state of the magma ocean allowed dissolved CO2 from the atmosphere to precipitate as diamond at depth. This explains Earth’s carbon-rich interior and suggests that redox evolution during accretion was an important variable in determining the composition of the terrestrial atmosphere.
DS202009-1624
2020
McCammon, C.A.Dorfman, S.M., Potapkin, V., Lv, M., Greenberg, E., Kupenko, I., Chumakov, A.I., Bi, W., Alp, E.E., Liu, J., Magrez, A., Dutton, S.E., Cava, R.J., McCammon, C.A., Gillet, P.Effects of composition and pressure on electronic states of iron in bridgmanite.American Mineralogist, Vol. 105, pp. 1030-1039. pdfMantleredox

Abstract: Electronic states of iron in the lower mantle's dominant mineral, (Mg,Fe,Al)(Fe,Al,Si)O3 bridgmanite, control physical properties of the mantle including density, elasticity, and electrical and thermal conductivity. However, the determination of electronic states of iron has been controversial, in part due to different interpretations of Mössbauer spectroscopy results used to identify spin state, valence state, and site occupancy of iron. We applied energy-domain Mössbauer spectroscopy to a set of four bridgmanite samples spanning a wide range of compositions: 10-50% Fe/total cations, 0-25% Al/total cations, 12-100% Fe3+/total Fe. Measurements performed in the diamond-anvil cell at pressures up to 76 GPa below and above the high to low spin transition in Fe3+ provide a Mössbauer reference library for bridgmanite and demonstrate the effects of pressure and composition on electronic states of iron. Results indicate that although the spin transition in Fe3+ in the bridgmanite B-site occurs as predicted, it does not strongly affect the observed quadrupole splitting of 1.4 mm/s, and only decreases center shift for this site to 0 mm/s at ~70 GPa. Thus center shift can easily distinguish Fe3+ from Fe2+ at high pressure, which exhibits two distinct Mössbauer sites with center shift ~1 mm/s and quadrupole splitting 2.4-3.1 and 3.9 mm/s at ~70 GPa. Correct quantification of Fe3+/total Fe in bridgmanite is required to constrain the effects of composition and redox states in experimental measurements of seismic properties of bridgmanite. In Fe-rich, mixed-valence bridgmanite at deep-mantle-relevant pressures, up to ~20% of the Fe may be a Fe2.5+ charge transfer component, which should enhance electrical and thermal conductivity in Fe-rich heterogeneities at the base of Earth's mantle.
DS202105-0767
2021
McCammon, C.A.Huang, R., Boffa Ballaran, T., McCammon, C.A., Miyajima, N., Frost, D.J.The composition and redox state of bridgmanite in the lower mantle as a function of oxygen fugacity.Geochimica et Cosmochimica Acta, Vol. 30, pp. 110-136.Mantleredox

Abstract: The chemistry of bridgmanite (Brg), especially the oxidation state of iron, is important for understanding the physical and chemical properties, as well as putting constraints on the redox state, of the Earth’s lower mantle. To investigate the controls on the chemistry of Brg, the Fe3+ content of Brg was investigated experimentally as a function of composition and oxygen fugacity (fo2) at 25 GPa. The Fe3+/?Fe ratio of Brg increases with Brg Al content and fo2 and decreases with increasing total Fe content and with temperature. The dependence of the Fe3+/?Fe ratio on fo2 becomes less steep with increasing Al content. Thermodynamic models were calibrated to describe Brg and ferropericlase (Fp) compositions as well as the inter-site partitioning of trivalent cations in Brg in the Al-Mg-Si-O, Fe-Mg-Si-O and Fe-Al-Mg-Si-O systems. These models are based on equilibria involving Brg components where the equilibrium thermodynamic properties are the main adjustable parameters that are fit to the experimental data. The models reproduce the experimental data over wide ranges of fo2 with a relatively small number of adjustable terms. Mineral compositions for plausible mantle bulk compositions can be calculated from the models as a function of fo2 and can be extrapolated to higher pressures using data on the partial molar volumes of the Brg components. The results show that the exchange of Mg and total Fe (i.e., ferric and ferrous) between Brg and Fp is strongly fo2 dependent, which allows the results of previous studies to be reinterpreted. For a pyrolite bulk composition with an upper mantle bulk oxygen content, the fo2 at the top of the lower mantle is ?0.86 log units below the iron-wüstite buffer (IW) with a Brg Fe3+/?Fe ratio of 0.50 and a bulk rock ratio of 0.28. This requires the formation of 0.7?wt.% Fe-Ni alloy to balance the raised Brg ferric iron content. With increasing pressure, the model predicts a gradual increase in the Fe3+/?Fe ratio in Brg in contrast to several previous studies, which levels off by 50 GPa. Oxygen vacancies in Brg decrease to practically zero by 40 GPa, potentially influencing elasticity, diffusivity and rheology in the top portion of the lower mantle. The models are also used to explore the fo2 recorded by inclusions in diamonds, which likely crystallized as Brg in the lower mantle, revealing oxygen fugacities which likely preclude the formation of some diamonds directly from carbonates, at least at the top of the lower mantle.
DS202201-0005
2021
McCammon, C.A.Beyer, C., Myhill, R., Marquardt, K., McCammon, C.A.A reversed redox gradient in Earth's mantle transition zone.Earth and Planetary Science Letters, Vol. 575, 12p.Mantleredox

Abstract: The Earth's mantle hosts a variety of reduced and oxidized phases, including iron-bearing alloys, diamond, and sulfide and carbonate melts. In the upper mantle, increasing pressure favors the stabilization of reduced iron-bearing phases via disproportionation of ferrous iron into ferric and metallic iron. Pressure-driven disproportionation is thought to continue into the transition zone, based on the extrapolation of experiments conducted at lower pressures. To test this hypothesis, we performed high-temperature and high-pressure experiments on basaltic and peridotitic compositions at pressures of 10 to 20 GPa, buffered at different oxygen fugacities. Under these conditions, majoritic garnet is the dominant ferric-iron bearing phase. We analyze our experimental run products for their ferric iron concentrations with EELS and Mössbauer spectroscopy. Contrary to expectations, results show that at iron saturation, ferric iron content of majorite peaks in the upper transition zone and then decreases between 500 and 650 km depth, destabilizing and resorbing reduced phases. This peak can be explained by decreases in the effective volume of ferrous minerals in transition zone assemblages. We also show that natural diamond-hosted majorite inclusions that equilibrated in the sublithospheric mantle grew from variably reduced fluids. These results are consistent with the idea that these diamonds formed during progressive reduction of an originally carbonatitic melt.
DS1994-1134
1994
McCammon, R.B.McCammon, R.B.ProspectorII: towards a knowledge base for mineral depositsMathematical Geology, Vol. 26, No. 8, pp. 917-936GlobalComputers, Program -ProspectorII
DS200412-1597
2004
McCamon, C.Proyer, A., Dachs, E., McCamon, C.pit falls in geothermobarometry of eclogites: Fe 3+ and changes in the mineral chemistry of omphacite at ultrahigh pressures.Contributions to Mineralogy and Petrology, Vol. 147, 3, pp. 305-329.TechnologyEclogite - geochemistry
DS1960-0707
1966
Mccamy, K.Mccamy, K., Meyer, R.P.Crustal Results of Fixed Multiple Shots in the Mississippi Embayment. In: the Earth Beneath the ContinentsGeophys. Monograph Series, Vol. 10, PP. 370-381.GlobalMid-continent
DS2003-0113
2003
McCandelss, T.E.Birkett, T.C., McCandelss, T.E., Hood, C.T.Petrology of the Renard igneous bodies: host rocks for diamond in the northern Otish8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractQuebec, Otish MountainsKimberlite petrogenesis
DS200412-0156
2003
McCandelss, T.E.Birkett, T.C., McCandelss, T.E., Hood, C.T.Petrology of the Renard igneous bodies: host rocks for diamond in the northern Otish Mountains Region, Quebec.8 IKC Program, Session 7, AbstractCanada, Quebec, Otish MountainsKimberlite petrogenesis
DS2002-0293
2002
McCandlessClements, B.P., Skelton, McCandless, HoodThe Buffalo Head Hills kimberlite province, AlbertaGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.22., p.22.AlbertaRegional geology - brief
DS2002-0294
2002
McCandlessClements, B.P., Skelton, McCandless, HoodThe Buffalo Head Hills kimberlite province, AlbertaGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.22., p.22.AlbertaRegional geology - brief
DS2003-0899
2003
McCandless, T.McCandless, T.Diamonds - unique commodity, unusual ore, viable exploration targetsPdac Abstract 2003, March 10, 1p.GlobalNews item, Diamond production
DS200512-0700
2005
McCandless, T.McCandless, T.Diamond indicators. Lead to economic deposits that may be considerable distance from an exploration site.Rough Diamond Review, No. 8, March pp. 15-17.Technology
DS200812-0492
2007
McCandless, T.Hunt, L., Stachel, T., McCandless, T.A study on diamonds and their mineral inclusions from the Renard kimberlites, Quebec. Stornoway35th. Yellowknife Geoscience Forum, Abstracts only p. 25-26.Canada, QuebecDiamond inclusions - Renard
DS200812-0729
2007
McCandless, T.McCandless, T.Kimberlites and other primary host rocks for diamonds in North America.Abstract 1p., 1p.Canada, United StatesGeochronology
DS200812-0861
2008
McCandless, T.Patterson, M., Francis, D., McCandless, T.Autoliths as samples of kimberlite magma.Goldschmidt Conference 2008, Abstract p.A727.Canada, AlbertaDeposit - Buffalo Head Hills
DS200812-0862
2008
McCandless, T.Patterson, M., Francis, D., McCandless, T.Kimberlite: magmas or mixtures? Hypabyssal dykes from Foxtrot.9IKC.com, 3p. extended abstractCanada, QuebecDeposit - Foxtrot
DS200912-0575
2009
McCandless, T.Patterson, M., Francis, D., McCandless, T.Kimberlites: magmas or mixtures?Lithos, In press available, 20p.Canada, QuebecGeochemistry - whole rock, Foxtrot
DS201312-0591
2013
McCandless, T.McCandless, T.The mystery of microdiamonds.Vancouver Kimberlite Cluster, abstract onlyTechnologyMicrodiamonds
DS201602-0224
2016
McCandless, T.McCandless, T.Perspectives on the Buffalo Head Hills kimberlites from 'new' data.Vancouver Kimberlite Cluster, Jan. 20, 1p. AbstractCanada, AlbertaDeposit - BHH
DS201708-1709
2017
McCandless, T.McCandless, T.Geology of the K6-252 kimberlite complex, Alberta.11th. International Kimberlite Conference, PosterCanada, Albertadeposit - K6-252
DS201712-2675
2017
McCandless, T.Barnett, W., Stubley, M., Hrkac, C., Hetman, C.M., McCandless, T.Kelvin and Faraday kimberlite emplacement geometries and implications for subterranean magmatic processes.45th. Annual Yellowknife Geoscience Forum, p. 4 abstractCanada, Northwest Territoriesdeposit - Kelvin, Faraday

Abstract: The Kennady North Project kimberlites are located approximately 280 kilometers east-northeast of Yellowknife, in the Northwest Territories of Canada. The unusual geometry and extent of the kimberlite magmatic system is revealed by renewed exploration drilling activities by Kennady Diamonds since 2012. It has become clear that the system comprises multiple intrusive dykes within which several volcaniclastic bodies have developed, all within 11 kilometres of the Gahcho Kué kimberlite cluster and diamond mine. The detailed exploration of the entire system provides unique evidence for subterranean volcanic conduit growth processes that may have scientific and practical exploration benefits. The identified Kennady North Project volcaniclastic bodies are named Kelvin, Faraday 1, Faraday 2 and Faraday 3, and have complex geometries atypical of the more common subvertical kimberlite pipes. Rather, these pipe-like bodies are inclined between 12 and 30 degrees towards the northwest. Kelvin has sharp angular change in trend towards the north. On-going detailed petrographic studies have shown that the pipes contain layers of complex volcaniclastic units with variable volumes of xenolithic fragments, as well as coherent magmatic layers. The pipe textures include evidence for high energy magma and country rock fragmentation processes typically observed in open volcanic systems. The pipes have developed within a shallow 20 degree northwest dipping kimberlite dyke system. Detailed structural geology studies, using fault observations in oriented and unoriented drill core, have identified at least two important fault-fracture trends. The first fault-fracture system is parallel to the dyke segments, and likely related to the intrusion of the dykes and the regional stress tensor during emplacement. The second fault system is subvertical and north-south striking, parallel to the lithological layering within the metasedimentary country rock. The north-south faults match the contact geometry of the Kelvin pipe’s north-south limb exactly. The dykes have been 3-D modelled along with the pipes. Three possible renditions of the dykes have been created, based on different interpretations of dyke segment continuity. The renditions have been labelled “Optimistic”, “Realistic” and “Pessimistic”. The assumptions made have important implications for developing dyke-type mineral resources. The realistic dyke model defines dyke segments that intersect the Kelvin pipe, and those intersections match geometric trends and irregularities in the pipe shape. The coincidental geometries strongly imply that the pipe development interacted with a penecontemporaneous dyke system. The north-south faults also controlled the local trend of Kelvin pipe development, possibly by enhancing fluid permeability, alteration and brecciation along the faults, connecting from one shallow dipping dyke to the next above. Breccia bodies have been observed on similar dipping dykes at Snap Lake mine that intersect fault structures. We conclude that the pipe development geometry and process is governed by a combination of stress, structure and magmatic fluids, and speculate on the nature of the energy required for fragmentation and development of the pipe at some still unknown depth in the crust.
DS201712-2704
2017
McCandless, T.McCandless, T., desGagnes, B., Shimell, M., Read, G.Geology of the K6-252 kimberlite complex, Alberta.45th. Annual Yellowknife Geoscience Forum, p. 102 abstract posterCanada, Albertadeposit - K6-252
DS201809-1993
2018
McCandless, T.Barnett, W., Stubley, M., Hetman, C., Uken, R., Hrkac, C., McCandless, T.Kelvin and Faraday kimberlite emplacement geometries and implications for subterranean magmatic processes.Mineralogy and Petrology, doi.org/10.1007/ s00710-018-0621-8 16p.Canada, Northwest Territoriesdeposit - Kelvin, Faraday

Abstract: The Kennady North Project kimberlites (Northwest Territories of Canada) comprises multiple shallow dipping dykes and several volcaniclastic bodies that have an unusual shallow plunging geometry and complex "pipe" shapes that are termed chonoliths. The detailed exploration of the entire system provides exceptional evidence for subterranean volcanic conduit growth processes. The possible processes leading to the development of the kimberlite bodies are discussed, with emphasis on the importance of the subsurface intrusive system geometry and the local stress tensor. Emplacement into a locally compressive stress regime (i.e. ?1 and ?2 inclined at a low angle to surface) could change the kimberlite emplacement geometries to that observed at Kennady North. Models are proposed for the development of the chonoliths, to emphasize aspects of the growth of kimberlite systems that are not well understood. The conclusions challenge or evolve current emplacement models and should influence kimberlite exploration and resource definition assumptions.
DS1982-0421
1982
Mccandless, T.E.Mccandless, T.E.The Mineralogy, Morphology and Chemistry of Detrital Minerals of a Kimberlitic and Eclogitic Nature, Green River Basin, wyoming.Msc. Thesis University Utah, Salt Lake City, 107P.United States, Wyoming, Rocky Mountains, ManillaMineral Chemistry
DS1984-0498
1984
Mccandless, T.E.Mccandless, T.E.Detrital Minerals of Mantle Origin in the Green River Basin, Wyoming.Society for Mining, Metallurgy and Exploration (SME)-American Institute of Mining, Metallurgical, and Petroleum Engineers (AIME)., SYMPOSIUM OUTLINE FALL MEETING DENVER OCTOBER 24TH. P. 13. (United States, Wyoming, Green River BasinGeochemistry, Morphology, Heavy Minerals
DS1984-0499
1984
Mccandless, T.E.Mccandless, T.E.Detrital Minerals of Mantle Origin in the Green River Basinwyoming.American Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) PREPRINT., No. 84-395, Oct. 26TH. 6P.United States, Wyoming, State Line, Rocky MountainsGeochemistry
DS1984-0500
1984
Mccandless, T.E.Mccandless, T.E., Nash, W.P.Detrital Minerals from a Mantle Source, Green River Basin, WyomingAmerican Mineralogist., IN PRESSUnited States, Wyoming, Rocky Mountains, Green River BasinGeochemistry
DS1985-0708
1985
Mccandless, T.E.Waldman, M.A., Mccandless, T.E., Dummett, H.T.Geology and Mineralogy of the Twin Knobs # 1 Lamproite Pikecounty, Arkansaw #2Geological Society of America (GSA), Vol. 17, No. 3, P. 196. (abstract.).United States, Gulf Coast, Arkansas, PennsylvaniaGeochronology, Evaluation
DS1985-0709
1985
Mccandless, T.E.Waldman, M.A., Mccandless, T.E., Dummett, H.T.Geology and Mineralogy of the Twin Knobs # 1 Lamproite Pikecounty, Arkansaw #1Preprint of Paper Presented Geological Society of America (gsa), 17P. 12 FIGS. 1 TABLE.United States, Gulf Coast, Arkansas, PennsylvaniaLamproite, Prospecting, Geophysics, Geochemistry
DS1986-0542
1986
McCandless, T.E.McCandless, T.E., Collins, D.S.A diamond graphite eclogite from the Sloan 2 kimberlite Colorado, USAProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 403-405ColoradoEclogite
DS1986-0543
1986
McCandless, T.E.McCandless, T.E., Gurney, J.J.Sodium in garnet and potassium in clinopyroxene: criteria forclassifying mantle eclogites #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 282-284South AfricaEclogite
DS1987-0777
1987
McCandless, T.E.Waldman, M.A., McCandless, T.E., Dummett, H.T.Geology and petrography of the Twin Knobs # 1 lamproite, Pike County, ArkansawMantle metasomatism and alkaline magmatism, edited E. Mullen Morris and, No. 215, pp. 205-216ArkansasAnalyses p. 212, 214
DS1989-0563
1989
McCandless, T.E.Gurney, J.J., McCandless, T.E., Kirkley, M.B., Robinson, D.N.Some initial observations on polycrystalline diamonds mainly from Orapa:abstractDiamond Workshop, International Geological Congress, July 15-16th. editors, BotswanaAnalyses, Diamond morphology
DS1989-0970
1989
McCandless, T.E.McCandless, T.E.Microdiamonds from the Sloan 1 and 2 kimberlites, Colorado, USADiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 44-46. AbstractColoradoMicrodiamonds, Diamond morphology
DS1989-0971
1989
McCandless, T.E.McCandless, T.E., Collins, D.S.A diamond-graphite eclogite from the Sloan 2 kimberlite Colorado, United States (US)Geological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1063-1069ColoradoEclogite, Sloan diatreme
DS1989-0972
1989
McCandless, T.E.McCandless, T.E., Gurney, J.J.Sodium in garnet and potassium in clinopyroxene:criteria for classifying mantle eclogites #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 827-832South AfricaDiamond morphology, Diamond eclogite
DS1989-0973
1989
McCandless, T.E.McCandless, T.E., Kirkley, M.B., Robinson, D.N., Gurney, J.J.Some initial observations on polycrystalline diamonds mainly from Orapa:Diamond Workshop, International Geological Congress, July 15-16th. editors, pp. 47-51BotswanaDiamond morphology, Diamond aggregates
DS1989-1157
1989
McCandless, T.E.Otter, M.L., Gurney, J.J., McCandless, T.E.The carbon isotope composition of Sloan diamonds #1Diamond Workshop, International Geological Congress, July 15-16th., pp. 76-79. AbstractColoradoGeochronology -Carbon Isotope, Deposit -Sloan diatremes
DS1990-0999
1990
McCandless, T.E.McCandless, T.E.Kimberlite xenocryst wear in high energy fluvial systems: experimentalstudiesJournal of Geochemical Exploration, Vol. 37, No. 3, July pp. 323-331Colorado, AustraliaGeochemistry -stream sediment, Evaluation
DS1990-1143
1990
McCandless, T.E.Otter, M.L., Gurney, J.J., McCandless, T.E.The carbon isotope composition of Sloan diamonds #2Eos, Vol. 71, No. 17, April 24, p. 644 Abstract onlyColorado, WyomingDiamond genesis, Geochronology -carbon iso
DS1991-1091
1991
McCandless, T.E.McCandless, T.E., Waldman, M.A., Gurney, J.J.Macro and micro diamonds from Arkansaw lamproites: morphology, inclusion sand isotope geochemistryProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 264-266ArkansasDiamond morphology, Diamond inclusions, comparison to Ellendale
DS1994-1135
1994
McCandless, T.E.McCandless, T.E., Waldman, M.A., Gurney, J.J.Macrodiamonds, microdiamonds from Murfreesboro lamproites: morphology, inclusions, carbon isotope geochemistry.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 78-97.ArkansasDiamond morphology, Deposit -Crater of Diamonds
DS1995-1194
1995
McCandless, T.E.McCandless, T.E.Sea Floor hydrothermal vent systems: protoenvironment for 13C depletede clogitic diamonds.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 365-367.GlobalEclogites, Microprobe
DS1995-1195
1995
McCandless, T.E.McCandless, T.E.A correlation between carbon isotopes and morphology for diamonds from theRoberts Victor mine.Eos, Vol. 76, No. 46, Nov. 7. p.F643. Abstract.South AfricaDiamond morphology, Deposit -Roberts Victor
DS1995-1196
1995
McCandless, T.E.McCandless, T.E., Gurney, J.J.Microdiamonds from kimberlites and lamproites: observations and ideas concerning their origin.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 368-370.Wyoming, South Africa, AustraliaMicrodiamonds, Lamproites
DS1995-1326
1995
McCandless, T.E.Nash, W.P., McCandless, T.E.Geochemical and morphological evaluation of indicator mineral anomalies in northeastern Utah and southwest Wyoming.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 393-395.Utah, WyomingGeochemistry, Green River Basin
DS1995-1362
1995
McCandless, T.E.Norton, D., McCandless, T.E.Kimberlites, fluids and diamonds: activity relations in the system magnesium-Ca Al K -C O -H.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 402-403.MantleFluids, magnesium, Calcium, Aluminum, Carbon, Oxygen, Hydrogen, Serpentinization
DS1996-0913
1996
McCandless, T.E.McCandless, T.E., Nash, W.P.Detrital mantle indicator minerals in southwestern Wyoming, USA: evaluation of mantle environment, hostExploration and Mining Geology, Vol. 5, No. 1, Jan. pp. 33-44.WyomingGreen River Basin, Igneous, diamond exploration, technology
DS1997-0488
1997
McCandless, T.E.Hausel, W.D., Kucera, R.E., McCandless, T.E., GregoryDiamond exploration potential of the Wyoming craton, western USA ... extends into southernmost Alberta.Wyom. Geol. Association Guidebook, No. 48, pp. 139-176.Alberta, Wyoming, SaskatchewanCraton - brieg mention of Wyoming province
DS1997-0750
1997
McCandless, T.E.McCandless, T.E., Gurney, J.J.Diamond eclogites: comparison with carbonaceous chondrites, shales and microbial carbon enriched Mid Ocean Ridge Basalt (MORB).Russian Geology and Geophysics, Vol. 38, No. 2, pp. 394-404.MantleEclogites, Organic, carbon
DS1998-0597
1998
McCandless, T.E.Hausel, W.D., Kucera, R.E., McCandless, T.E., GregoryMantle derived diatremes in the southern Green River Basin, Wyoming, USA7th International Kimberlite Conference Abstract, pp. 320-1.WyomingDiatremes, Deposit - Cedar Mountain
DS1998-0863
1998
McCandless, T.E.Letendre, J., McCandless, T.E., Eastoe, C.J.Morphology and carbon isotope composition of microdiamonds from Dachine, French Guiana.7th International Kimberlite Conference Abstract, pp. 500-2.French GuianaDiamond morphology, resorption, Deposit - Dachine
DS1998-0972
1998
McCandless, T.E.McCandless, T.E.Kimberlites: the products of deep seated subduction7th International Kimberlite Conference Abstract, pp. 558-0.Southern Africa, North AmericaTectonics, subduction, Magmatism
DS1998-1267
1998
McCandless, T.E.Ruiz, J., McCandless, T.E., Helmstaedt, H.H.Eclogites from the Colorado Plateau: a Phanerozoic record of subduction beneath North America.7th. Kimberlite Conference abstract, pp. 757-9.Colorado PlateauSubduction, Eclogites
DS1999-0452
1999
McCandless, T.E.McCandless, T.E.Kimberlites: mantle expressions of deep seated subduction7th International Kimberlite Conference Nixon, Vol. 2, pp. 545-49.United States, Wyoming, Southern AfricaSubduction - slab, Tectonics - hot spots, magmatism
DS1999-0453
1999
McCandless, T.E.McCandless, T.E., Letendre, J., Eastoe, C.J.Morphology and carbon isotope composition of microdiamonds from Dachine, French Guiana.7th International Kimberlite Conference Nixon, Vol. 2, pp. 550-56.French GuianaMicro diamonds, diamond morphology, eclogite, Deposit - Dachine
DS1999-0615
1999
McCandless, T.E.Ruiz, J., McCandless, T.E., Helmstaedt, H.H.Re Os model ages for eclogite xenoliths from the Colorado Plateau, USA7th International Kimberlite Conference Nixon, Vol. 2, pp. 736-40.Colorado Plateau, New MexicoGeochronology, subduction, diatreme, Moses Rock, Garnet Ridge, Mule Ear
DS2000-0640
2000
McCandless, T.E.McCandless, T.E.Diamonds, kimberlite and plate tectonics: is there a connection?Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) 2000, 3p. abstractMantleTectonics - subduction
DS2002-1026
2002
McCandless, T.E.McCandless, T.E.Global diamond exploration - a matter of scaleSociety of Economic Geologists, Abstracts, pp. 29-30.Northwest Territories, Alberta, OntarioExploration - brief overview, Economics
DS2003-0049
2003
McCandless, T.E.Aulbach, S., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.The lithospheric mantle beneath the Buffalo Head Terrane, Alberta: xenoliths from the8 Ikc Www.venuewest.com/8ikc/program.htm, Session 4, AbstractAlbertaMantle geochemistry, Geochronology
DS2003-0149
2003
McCandless, T.E.Boyer, L.P., Hood, C.T., McCandless, T.E., Skelton, D.N., Tosdal, R.D.Volcanology of the Buffalo Hills kimberlites, Alberta, Canada8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractAlbertaKimberlite geology and economics, Volcanism
DS2003-0150
2003
McCandless, T.E.Boyer, L.P., Hood, C.T., McCandless, T.E., Skelton, D.N., Tosdal, R.M.Volcaniclastic kimberlites of the Buffalo Head Hills, Alberta, CanadaGeological Association of Canada Annual Meeting, Abstract onlyAlbertaPetrology
DS2003-0151
2003
McCandless, T.E.Boyer, L.P., McCandless, T.E., Tosdal, R.M., Russell, J.K.Diamondiferous volcanoclastics of the Buffalo Head Hills kimberlites, northern AlbertaGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.327.AlbertaPetrology
DS2003-0317
2003
McCandless, T.E.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.Inclusions in diamonds from the K10 and K14 kimberlites, Buffalo Hills, Alberta8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractAlbertaDiamonds - inclusions
DS2003-0600
2003
McCandless, T.E.Hood, C.T., McCandless, T.E.Systematic variations in xenocryst mineral composition at the Province scale, Buffalo8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractAlbertaDiamond exploration - mineralogy, Deposit - Buffalo Hills
DS2003-0900
2003
McCandless, T.E.McCandless, T.E., Dummett, H.T.Some aspects of chromian spinel (chromite) chemistry in relation to diamondGeological Association of Canada Annual Meeting, Abstract onlyGlobalGeochemistry
DS200412-0074
2003
McCandless, T.E.Aulbach, S., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.The lithospheric mantle beneath the Buffalo Head Terrane, Alberta: xenoliths from the Buffalo Hills kimberlites.8 IKC Program, Session 4, AbstractCanada, AlbertaMantle geochemistry Geochronology
DS200412-0075
2004
McCandless, T.E.Aulbach, S., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.Genesis and evolution of the lithospheric mantle beneath the Buffalo Head Terrane, Alberta ( Canada).Lithos, Vol. 77, 1-4, Sept. pp. 413-451.Canada, AlbertaTrace elements, Os Hf isotopes, geochronology, metasoma
DS200412-0090
2004
McCandless, T.E.Banas, A., Stachel, T., McCandless, T.E.Diamonds from the K252, K11 and K 19 kimberlites, Buffalo Head Hills, Alberta Canada.Geological Association of Canada Abstract Volume, May 12-14, SS14-10 p. 269.abstractCanada, AlbertaDiamond inclusions, morphology
DS200412-0198
2003
McCandless, T.E.Boyer, L.P., Hood, C.T., McCandless, T.E., Skelton, D.N., Tosdal, R.M.Volcaniclastic kimberlites of the Buffalo Head Hills, Alberta, Canada.Geological Association of Canada Annual Meeting, Abstract onlyCanada, AlbertaPetrology
DS200412-0199
2003
McCandless, T.E.Boyer, L.P., McCandless, T.E., Tosdal, R.M., Russell, J.K.Diamondiferous volcanoclastics of the Buffalo Head Hills kimberlites, northern Alberta Canada.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.327.Canada, AlbertaPetrology
DS200412-0417
2004
McCandless, T.E.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.Inclusions in diamonds from K14 and K10 kimberlites, Buffalo Hills, Alberta, Canada: diamond growth in a plume?Lithos, Vol. 77, 1-4, Sept. pp. 99-111.Canada, AlbertaDiamond inclusions, Carbon isotopes, nitrogen aggregati
DS200412-0849
2003
McCandless, T.E.Hood, C.T., McCandless, T.E.Systematic variations in xenocryst mineral composition at the Province scale, Buffalo Hills kimberlites, Alberta Canada.8 IKC Program, Session 8, AbstractCanada, AlbertaDiamond exploration - mineralogy Deposit - Buffalo Hills
DS200412-0850
2004
McCandless, T.E.Hood, C.T.S., McCandless, T.E.Systematic variations in xenocryst mineral composition at the province scale, Buffalo Hills kimberlites, Alberta Canada.Lithos, Vol. 77, 1-4, Sept. pp. 733-747.Canada, AlbertaMineral chemistry, Proterozoic mantle, pyrope, chromian
DS200412-1260
2003
McCandless, T.E.McCandless, T.E., Dummett, H.T.Some aspects of chromian spinel (chromite) chemistry in relation to diamond exploration.Geological Association of Canada Annual Meeting, Abstract onlyTechnologyGeochemistry
DS200512-0063
2004
McCandless, T.E.Banas, A., Stachel, T., Muehlenbachs, K., McCandless, T.E.Origin of diamonds from the K252, K91 and K11 kimberlites, Buffalo Head Hills, Alberta, Canada.32nd Yellowknife Geoscience Forum, Nov. 16-18, p.3-4. (talk)Canada, AlbertaDiamond morphology, genesis
DS200712-0050
2007
McCandless, T.E.Banas, A., Stachel, T., Muehlenbachs, K., McCandless, T.E.Diamonds from the Buffalo Head Hills, Alberta: formation in a non-conventional setting.Lithos, Vol. 93, 1-2, pp. 199-213.Canada, AlbertaDeposit - Buffalo Head Hills area
DS200712-0819
2007
McCandless, T.E.Patterson, M.V., McCandless, T.E.Geochemistry of kimberlitic rocks from the Otish Mountains of northern Quebec.Geological Association of Canada, 1 pg. abstract p.62-63.Canada, QuebecMineral chemistry
DS200812-0493
2008
McCandless, T.E.Hunt, L., Stachel, T., Simonetti, T., Armstrong, J., McCandless, T.E.Microxenoliths from the Renard kimberlites, Quebec.Northwest Territories Geoscience Office, p. 35-36. abstractCanada, QuebecBrief overview - Stornoway
DS200912-0222
2009
McCandless, T.E.Fitzgerald, C.E., Hetman, C.M., Lepine,I., Skelton, D.S., McCandless, T.E.The internal geology and emplacement history of the Renard 2 kimberlite, Superior Province, Quebec, Canada.Lithos, In press - available 29p.Canada, QuebecDeposit - Renard
DS200912-0786
2009
McCandless, T.E.Van Rythoven, A., McCandless, T.E., Schulze, D.J.,Bellis, A., Taylor, I.A., Liu, Y.In-situ analysis of diamonds and their mineral inclusions from the Lynx kimberlite dyke complex, central Quebec.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyCanada, QuebecDeposit - Lynx
DS201112-1077
2011
McCandless, T.E.Van Rythoven, A.D., McCandless, T.E., Schulze, D.J., Bellis, A., Taylor, L.A., Liu, Y.Diamond crystals and their mineral inclusions from the Lynx kimberlite dyke complex, central Quebec.The Canadian Mineralogist, Vol. 49, 3, pp. 691-706.Canada, QuebecDiamond morphology - Lynx dyke
DS201212-0320
2012
McCandless, T.E.Hunt, L., Stachel, T., Grutter, H., Armstrong, J., McCandless, T.E., Simonetti, A., Tappe, S.Small mantle fragments from the Renard kimberlites, Quebec: powerful recorders of mantle lithosphere formation and modification beneath the eastern Superior Craton.Journal of Petrology, Vol. 53, 8, pp. 1597-1635.Canada, QuebecDeposit - Renard
DS201212-0321
2012
McCandless, T.E.Hunt, L., Stachel, T., McCandless, T.E., Armstrong, J., Muelenbachs, K.Diamonds and their mineral inclusions from the Renard kimberlites in Quebec.Lithos, in press availableCanada, QuebecDeposit - Renard
DS201512-1942
1989
McCandless, T.E.McCandless, T.E.Microdiamonds from the Sloan 1 and 2 kimberlites, Colorado, USA.28th International Geological Congress, Washington DC, Workshop on Diamonds, extended abstracts, pp. 44-46.United States, Colorado PlateauMicrodiamonds
DS201512-1943
1999
McCandless, T.E.McCandless, T.E., Letendre, J., Eastoe, C.J.The morphology and carbon isotope chemistry of microdiamonds from the Dachine Diamondiferous body, French Guiana.Proceedings of rhe 7th International Kimberlite Conference, Vol. 2, pp. 550-556.South America, French GuianaMicrodiamonds
DS201512-1944
1994
McCandless, T.E.McCandless, T.E., Waldman, M.A., Gurney, J.J.Macro- and microdiamonds from Arkansas lamproites: morphology, inclusions and isotope geochemistry.Proceedings of the 5th. International Kimberlite Conference, Vol. 2, pp. 78-97.United States, ArkansasMicrodiamonds

Abstract: The first report of diamond in igneous rock in the United States originated at Prairie Creek, Arkansas. We have examined the morphological, carbon isotope, and inclusion characteristics of diamonds from Prairie Creek, and from the Twin Knobs # 1, #2, Black Lick, and American lamproites. White is the most common macrodiamond color at Prairie Creek (62% of total), with 20% brown and 16% yellow. This contrasts with Australian lamproites where brown predominates, and with other North American localities such as the Sloan, Colorado kimberlites where yellow is rare. Lamination lines indicate ductile deformation at mantle conditions. The macrodiamonds are very resorbed; 82% are equiform or distorted tetrahexahedroida and none are octahedra. Low relief surfaces indicate prolonged and/or intense resorption. Microdiamonds differ dramatically, with octahedra and fragn~ents common and tetrahexahedroida abscnL Serrate laminae, knob-like asperities, pointed plates, ribbing, and non-uniform resorption are the most common surface features. Diamonds from the Twin Knobs # 1 lamproite are similar to microdiamonds with respect to size and surface features. Magnetite and olivine (F093) are the only primary inclusions foqnd in the diamonds, although inclusions of peridotitic and eclogitic parageneses have been reported in previous studies. Carbon isotope B13c values for Prairie Creek macrodiamonds peak at-3.0 to -6.2 %o (ave. -4.7 %o for 19 stones) and -10.3 to -10.6 %o (ave. -10.5 %o for 2 stones). The diamonds with magnetite and olivine inclusions have B13c values of -5.1 %o and -4.0 %o respectively. Microdiamonds from Prairie Creek, Twin Knobs #2, American, and Black Lick are similar to Prairie Creek macrodiamonds ( -0.5 to -7 .8; ave. -4.1 %o for 8 stones). A Prairie Creek and a Black Lick microdiamond have B13c values of -26.1 and -25.2%orespectively, and the latter exhibits non-uniform resorption. Lamination lines on macrodiamonds and xenocrystic surface features on microdiamonds imply that both are xenocrysts in lamproite. Carbon isotopes are characteristic of a peridotitic or primordial carbon reservoir. Two 13cdepleted microdiamonds may be from a subducted carbon source. In comparison to macrodiamond populations from most kimberlites, Prairie Creek macrodiamonds are intensely resorbed, and lamproite may be more corrosive than kimberlite \\ ith respect to diamond resorption. Microdiamonds were probably encapsulated in xenolith material ani.! esca•,)ed resorption. The differences in size and color of Prairie Creek macrodiamonds relative to Sloan kimberlitic diamonds are genetic, and may be related to their formation in lithosphere of differing age and tectonic history.
DS1989-0076
1989
McCann, D.M.Baria, R., Jackson, P.D., McCann, D.M.Further development of a high frequency seismic source for use inboreholesGeophysical Prospecting, Vol. 37, No. 1, January pp. 31-52GlobalGeophysics, Seismic - drillholes
DS1920-0112
1922
Mccann, W.S.Mccann, W.S.Geology and Mineral Deposits of Bridge River AreaGeological Survey of Canada MEMOIR., No. 130, GEOL. SER. 1111, 115P. PP. 74-75.Canada, British ColumbiaBlank
DS1992-1025
1992
McCarn, D.W.McCarn, D.W., Carr, J.R.Influence of numerical precision and equation solution algorithm on computation of kriging weightsComputers and Geosciences, Vol. 18, No. 9, pp. 1127-1167GlobalGeostatistics, Kriging weights
DS1998-0070
1998
McCarroll, D.Ballantyne, C.K., McCarroll, D., Fifield, L.K.High resolution reconstruction of the last ice sheet in northwest ScotlandTerra Nova, Vol. 10, No. 2, pp. 63-68.ScotlandGeomorphology, Glacial
DS201112-0658
1997
McCarron, J.McCarron, J.Mantle xenoliths from Queensland and South Australia.Thesis: 'Macquarie University Msc. , AustraliaThesis: note availability based on request to author
DS1988-0450
1988
McCartan, L.McCartan, L., Architzel, R.J.Heat flow map of the Eastern United StatesUnited States Geological Survey (USGS) Map, (Colour), No. MF 2057 2 - 1:2, 500, 000; 2, 1:7, 500, 000 $4.80Appalachia, MidcontinentGeophysics, Heat flow
DS1991-1092
1991
McCartan, L.McCartan, L., Gettings, M.E.Possible relationship between seismicity and warm intrusive bodies in theCharleston, South Carolina, and New Madrid Missouri areasUnited States Geological Survey (USGS) Bulletin, No. 1953, 18pGlobalGeophysics -seismics, Intrusions
DS1991-1093
1991
McCarten, L.McCarten, L., Snyder, S.L., Stover, C.W.Map showing the relationship to selected mafic and ultramafic bodies in the crust of the eastern United States to seismically active areasUnited States Geological Survey (USGS) Map, No. MF-2143, 1, 2, 500, 000 $ 3.50AppalachiaMafic, ultramafics, Seismics
DS1987-0736
1987
McCarthy, D.Thompson, G.R., Walker, S., McCarthy, D.Zoned K bentonites of western MontanaGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p.867. abstracMontanaSweetgrass Arch
DS200912-0812
2009
mcCarthy, D.D.Whitelaw, G.S., mcCarthy, D.D., Tsuji, L.J.S.The Victor diamond mine environmental assessment process: a critical first.Impact Assessment and Project Appraisal, Vol. 27, Sept, no. 3, pp. 205-215.Canada, OntarioDeposit - Victor
DS201112-1060
2011
McCarthy, D.D.Tsuji, L.J.S., McCarthy, D.D., Whitelaw, G.S., McEachren, J.Getting back to basics: the Victor diamond mine environmental assessment scoping process and the issue of family based traditional lands versus reg. traplinesImpact assessment and Project Appraisal, March Vol. 29, no. 1, pp. 37-47.Canada, Ontario, AttawapiskatLegal
DS201212-0736
2011
McCarthy, D.D.Tsuji, L.J.S., McCarthy, D.D., Whielaw, G.S., McEachren, J.Getting back to basics: the Victor diamond mine environmental assessment scoping process and the issue of family based traditional lands versus traplines.Impact Assessment and Project Aapraisal, Vol. 29, 1, pp. 37-47.Canada, Ontario, AttawapiskatEnvironment
DS201212-0775
2009
McCarthy, D.D.Whitelaw, G.S., McCarthy, D.D., Tsuji, L.J.S.The Victor diamond mine environmental assessment process: a critical First Nation perspective.Impact Assessment and Project Aapraisal, Vol. 27, 3, pp. 205-215.Canada, Ontario, AttawapiskatEnvironment
DS1995-1197
1995
McCarthy, D.J.McCarthy, D.J., Puffer, S.M.Diamonds and rust on Russia road to privitization - the profits and pit falls for western managers.Columbia Jour W., Vol. 30, No. 3, Fall, pp. 56-69.RussiaEconomics
DS1990-1000
1990
McCarthy, J.McCarthy, J., et al.PACE lithospheric investigation of the Colorado PlateauEos, Vol. 71, No. 43, October 23, p. 1563 AbstractColorado PlateauGeophysics -seismics, Plateau
DS1990-1161
1990
McCarthy, J.Parsons, T., McCarthy, J., Howie, J.M., Thompson, G.A.Full wavelength imaging of Colorado Plateau, Arizona, USATerra, Abstracts of Deep Seismic reflection profiling of the Continental, Vol. 2, December abstracts p. 203ArizonaGeophysics -Seismics, Crust
DS1994-1136
1994
McCarthy, J.McCarthy, J., Parsons, T.Insights into kinematic Cenozoic evolution of Basin and Range-Colorado plateau transition from seismic refraction and reflection dataGeological Society of America (GSA) Bulletin, Vol. 106, No. 6, June pp. 747-7599Basin and RangeGeophysics -seismics, Tectonics
DS1995-1442
1995
McCarthy, J.Parsons, T., McCarthy, J.The active southwest margin of the Colorado Plateau: uplift of mantleoriginGeological Society of America (GSA) Bulletin, Vol. 107, No. 2, Feb. pp. 139-147Colorado Plateau, Utah, ArizonaMantle, Tectonics, subduction
DS1996-1074
1996
McCarthy, J.Parsons, T., McCarthy, J., Criley, E.E.Crustal structure of the Colorado Plateau Arizona: application of new long offset seismic dat a analysis...Journal of Geophysical Research, Vol. 101, No. 5, May 10, pp. 1173-94.Arizona, Colorado PlateauGeophysics -seismics, Structure, tectonics
DS1940-0053
1942
Mccarthy, J.R.Mccarthy, J.R.Fire in the Earth. the Story of the DiamondNew York: Harper And Bros., 263P.South AfricaHistory, Kimberley
DS1940-0125
1946
Mccarthy, J.R.Mccarthy, J.R.Fire in the Earth: the Story of the DiamondLondon: R. Hale, 250P.South AfricaKimberlite
DS1997-0751
1997
McCarthy, T.C.McCarthy, T.C., Patino Douce, A.E.Experimental evidence for high temperature felsic melts formed during basaltic intrusion of the deep crust.Geology, Vol. 25, No. 5, May pp. 463-466.MantleBasalts, Experimental petrology
DS1986-0544
1986
McCarthy, T.S.McCarthy, T.S., Charlesworth, E.G., Stanistreet, I.G.Post Transvaal structural features of the northern portion of the Witwatersrand BasinEconomic Geology Research Unit, Circular No. 191, 21pSouth AfricaStructure, Basin
DS1992-0952
1992
McCarthy, T.S.Linton, P.L., McCarthy, T.S.The use of discriminant function analysis for the stratigraphic classification of Klipriviersberg Group and Allanridge formation samplesEconomic Geology Research Unit, University of Witwatersrand, Inf. Circular No. 253, 14pSouth AfricaGeostatistics, Stratigraphy
DS1995-0201
1995
McCarthy, T.S.Brandl, G., McCarthy, T.S., Andreoli, M.A.G., AndersenTectonic and lineament investigations of the Vaalputs area, Namaqualand, South Africa: implications rifting..Centennial Geocongress (1995) Extended abstracts, Vol. 1, p. 445-448. abstractSouth AfricaTectonics
DS1995-0568
1995
McCarthy, T.S.Friese, A.E.W., Charlesworth, E.G., McCarthy, T.S.Tectonic processes within the Kaapvaal Craton during the Kibaran Orogeny:structural, geophysical, geochronEconomic Geol. Research Unit, No. 292, 67pSouth AfricaWitwatersrand Basin, Grenville Orogeny, geochronology, isotope
DS1997-0752
1997
McCarthy, T.S.McCarthy, T.S., Barry, M., Sternberg, H.The gradient of the Okavango fan, Botswana, and its sedimentological and tectonic implications.Journal of African Earth Sciences, Vol. 24, No. 1-2, Jan. pp. 65-78.BotswanaSedimentology, Alluvial - fan
DS200812-0730
2007
McCarthy, T.S.McCarthy, T.S., Allan, J.G.A possible new alluvial diamond field related to the Klipspringer kimberlite swarm, South Africa.South African Journal of Geology, Vol. 110, 4, pp. 503-510.Africa, South AfricaDeposit - Klipspringer
DS1984-0501
1984
Mccaughan, DYSON AND CO.Mccaughan, DYSON AND CO.The Australian Diamond Exploration Joint-ventureMccaughan Dyson And Co., 14P. JANUARY.Australia, Western AustraliaHistory, Review Of Investment
DS1989-1634
1989
McCauley, J.R.Wilson, F.W., McCauley, J.R.The relationship of remote sensing anomalies to the real world-examples from the midcontinent and the CUSMAP study areasUnited States Geological Survey (USGS) Open file, United States Geological Survey (USGS)-Missouri G.S. Symp: Mineral resource potential of, p. 45. (abstract.)MidcontinentTectonics, Remote sensing
DS1975-0805
1978
Mccausland, J.Mccausland, J.Race to Claim Likely Bits of the Kimberleys. Derby.!Unknown., Australia, Western AustraliaDiamond
DS201906-1322
2019
McCausland, P.McCausland, P., Higgins, M., LeCheminant, A., Jourdan, F., Hamilton, M., Murphy, J.B.Laurentia during the mid-Edicacaran: paleomagnetism and 580 Ma age of the Saint Honore alkali intrusion and related dykes, Quebec. GAC/MAC annual Meeting, 1p. Abstract p. 141.Canada, Quebecdeposit - Saint Honore

Abstract: We sampled the mid-Ediacaran Saint-Honoré alkali intrusion and related dykes in the Saguenay City region of Québec for paleomagnetic and U-Pb, 40Ar/39Ar geochonologic study. 40Ar/39Ar geochronology of phlogopite separates from carbonatite of the central intrusion return plateau ages with a weighted mean of 578.3 ± 3.5 Ma. Baddeleyite from a phoscorite dyke provides a concordant age of 580.25 ± 0.87 Ma for the crystallization of the dykes associated with the St-Honoré intrusive complex. Paleomagnetic results from the intrusion itself and related carbonatite and lamprophyre dykes exhibit some streaking between higher to moderate inclination directions, even at the site level, after screening to remove a steep, present-day viscous remanence. The predominant St-Honoré mean direction (13 sites), which is primary (baked contact test on the host Lac St-Jean anorthosite), is D = 119, I = 72.3°; ?95 = 9.5°, retained at higher coercivity and to high unblocking temperatures by titanomagnetite. Assuming a geocentric axial dipole, this result places the St. Honoré locality at 57° S at ~ 580 Ma, implying that Laurentia straddled mid-paleolatitudes at that time. Notably, the paleopole location at 27.2° N, 320.7 E (dp = 15°, dm = 17°) is consistent with similar mid-Ediacaran age paleopoles which place Laurentia at mid- to high paleolatitudes. The Saint-Honoré result implies that Laurentia had moved from low latitude in the early Ediacaran to higher southern paleolatitudes by 580-570 Ma, and then back to low paleolatitudes by as early as 564 Ma. Viewed as apparent polar wander (APW), this motion traces an 'Ediacaran loop' that can also be seen in similar-aged paleomagnetic results from at least two other paleocontinents. The similar APW loops suggest a role for true polar wander in Ediacaran geodynamics, and perhaps help to define a longitudinally-constrained global Ediacaran paleogeography.
DS2003-1354
2003
McCausland, P.J.A.Symons, D.T.A., Erdmer, P., McCausland, P.J.A.New 42 Ma cratonic North American paleomagnetic pole from the Yukon underscoresCanadian Journal of Earth Sciences, Vol. 40, 10, Oct. pp. 1321-34.YukonGeochronology
DS2003-1355
2003
McCausland, P.J.A.Symons, D.T.A., Erdmer, P., McCausland, P.J.A.New 42 Ma cratonic North American paleomagnetic pole from the Yukon underscoresCanadian Journal of Earth Science, Vol. 40, 10, pp. 1321-34.YukonGeochronology, magnetics
DS200412-1959
2003
McCausland, P.J.A.Symons, D.T.A., Erdmer, P., McCausland, P.J.A.New 42 Ma cratonic North American paleomagnetic pole from the Yukon underscores another Cordilleran paleomagnetism geology conunCanadian Journal of Earth Sciences, Vol. 40, 10, pp. 1321-34.Canada, YukonGeochronology, magnetics
DS201312-0977
2013
McCausland, P.J.A.Wilson, G.C., McCausland, P.J.A.Canadian meteorites: a brief review.Canadian Journal of Earth Sciences, Vol. 50, pp. 4-13.CanadaMeteorite
DS201312-0592
2013
McCelland, W.C.McCelland, W.C., Lapen, T.J.Linking time to the pressure temperature path of ultrahigh pressure rocks.Elements, Vol. 9, 4, August in pressMantleUHP
DS1970-0135
1970
Mcclatchie, L.Mcclatchie, L.Geological Report on the West Narringha Diamond ProjectNew South Wales Geological Survey Report., GS 1972/207, (UNPUBL.).AustraliaKimberlite
DS202003-0364
2019
McClaure, S.F.Sun, Z., Palke, A. C., Muyal, J., DeGhionno, D., McClaure, S.F.Geographic origin determination of alexandrite.Gems & Gemology, Vol. 55, 4, pp. 660-681.Russia, South America, Brazil, Africa, Tanzania, Zimbabwe, India, Asia, Sri Lankaalexandrite

Abstract: The gem and jewelry trade has come to place increasing importance on the geographic origin of alexandrite, as it can have a significant impact on value. Alexandrites from Russia and Brazil are usually more highly valued than those from other countries. In 2016, GIA began researching geographic origin of alexandrite with the intent of offering origin determination as a laboratory service. Unfortunately, collecting reliable samples with known provenance can be very difficult. Alexandrite is often recovered as a byproduct of mining for other gemstones (e.g., emerald and corundum), so it can be difficult to secure reliable parcels of samples because production is typically erratic and unpredictable. The reference materials studied here were examined thoroughly for their trace element chemistry profiles, characteristic color-change ranges under daylight-equivalent and incandescent illumination, and inclusion scenes. The data obtained so far allow us to accurately determine geographic origin for alexandrites from Russia, Brazil, Sri Lanka, Tanzania, and India. Future work may help to differentiate alexandrites from other localities.
DS1995-1198
1995
McClay, K.McClay, K., Dooley, T.Analogue models of pull apart basinsGeology, Vol. 23, No. 8, August pp. 711-714Andes, ArgentinaBasins, Tectonics
DS1995-1839
1995
McClay, K.Storti, F., McClay, K.Influence of syntectonic sedimentation on thrust wedges in analoguemodelsGeology, Vol. 23, No. 11, Nov. pp. 999-1002GlobalAccretionary prisms, Models
DS201502-0053
2010
McClay, K.deVera, J., Granado, P., McClay, K.Structural evolution of the Orange Basin gravity-driven system, offshore Namibia.Marine and Petroleum Geology, Vol. 27, 1, pp. 223-237.Africa, NamibiaStructure
DS1991-1094
1991
McClay, K.R.McClay, K.R.Deformation mechanics in analogue models of extensional fault systemsDeformation Mechanisms, Rheology and Tectonics, editors Knipe, R.J., No. 54, pp. 445-453GlobalStructure -faults, Models -extension
DS1991-1095
1991
McClay, K.R.McClay, K.R., Waltham, D.A., Scott, A.D., Abousetta, A.Physical and seismic modelling of listric normal fault geometriesThe geometry of normal faults, editors Roberts, A.M., Yielding, G., No. 56, pp. 231-239GlobalStructure -faults, Fault geometry -listric
DS1993-0988
1993
McClay, K.R.McClay, K.R.Thrust tectonicsChapman-Hall Publ, 450pBritish Columbia, Cordillera, Alps, Pyrenees, HimalayasBook -table of contents, Thrust tectonics
DS1997-0576
1997
McClay, K.R.Keep, M., McClay, K.R.Analogue modelling of multiphase rift systemsTectonophysics, Vol. 273, No. 3-4 May 30, pp. 239-270GlobalTectonics
DS1998-0973
1998
McClay, K.R.McClay, K.R., Dooley, T., Lewis, G.Analog modeling of progradational delta systemsGeology, Vol. 26, No. 9, Sept. pp. 772-4GlobalDelta systems, basins, model, Graben, Fold thrust, tectonics
DS2003-0901
2003
McClearn, M.McClearn, M.Diamond works seeks its fortune in war torn Africa. History of original area KoiduCanadian Business, June pp. 39,40.Sierra Leone, AngolaNews item, DiamondWorks
DS1995-1199
1995
McCleary, J.McCleary, J.Metallic and industrial mineral assessment report for the Steen River Prospects.Alberta Geological Survey, MIN 19950015AlbertaExploration - assessment, Troymin Resources Ltd.
DS1996-0914
1996
McClelland, G.E.McClelland, G.E., Scheiner, B.J., Muhtadi, O., Keane, J.Practical aspects of international management and processingSociety of Mining Engineers, 118p. see pricesUnited StatesBook -ad, Mining -practical processing
DS1989-1333
1989
McClelland, W.C.Samson, S.D., McClelland, W.C., Patchett, P.J., Gehrels, G.E.Evidence from neodynium isotopes for mantle contributions to Phanerozoiccrustal genesis in the Canadian CordilleraNature, Vol. 337, No. 6209, Feb. 23, pp. 705-708CordilleraIsotope, Mantle genesis
DS200612-0517
2006
McClelland, W.C.Hacker, B.R., McClelland, W.C., Liou, J.G.Ultrahigh pressure metamorphism: deep continental subduction.Geological Society of America, Special Paper, No. 403, 200p.China, RussiaUHP, geochronology, subduction
DS200612-0886
2006
McClelland, W.C.McClelland, W.C., Power, S.E., Gilotti, J.A., Mazdab, F.K., Wopenka, B.U Pb SHRIMP geochronology and trace element geochemistry of coesite bearing zirocons, north east Greenland Caledonides.Geological Society of America, Special Paper, No. 403, pp. 23-44.Europe, GreenlandCoesite
DS200612-0887
2006
McClemore, V.T.McClemore, V.T., Turner, D.Sustainable development and exploration.Mining Engineering, Feb. pp. 56-61.GlobalEconomics
DS2001-1237
2001
McClenaghanWilkinson, L., Harris, J., Kjarsgaard, B., McClenaghanInfluence of till thickness and texture on till geochemistry in the Lac deGras area, applications..Geological Survey of Canada Current Research, C9, 26p.Northwest TerritoriesRegional kimberlite exploration, Geochemistry - till, geomorphology
DS1996-1429
1996
McClenaghan, B.Thorleifson, H., McClenaghan, B., Ward, B., et al.Indicator mineral methods in diamond explorationGeological Survey of Canada Colloquium, Jan. 22-24th., 1p. abstractNorthwest TerritoriesExploration -indicators
DS1999-0454
1999
McClenaghan, B.McClenaghan, B., Kjarsgaard, Stirling, Pringle, BergerMineralogy and chemistry of the A4 kimberlite and associated glacialsediments, Kirkland Lake, Ontario.Geological Survey of Canada (GSC) Open file, No. 3769, 162p. plus Disc $ 65.00Ontario, Kirkland LakeGeochemistry - indictor minerals, Deposit - A4
DS1999-0464
1999
McClenaghan, B.McMartin, I., McClenaghan, B.Till geochemistry and sampling techniques in shield terrainAssocation of Exploration Geologists (AEG) 19th. Drift Exploration Glaciated, S.C., pp. 67-94.Cordillera, British ColumbiaGeomorphology, glacial, geochemistry, Drift prospecting - not specific to diamonds
DS2003-0902
2003
McClenaghan, B.McClenaghan, B.The Seed and Triple B kimberlites and associated glacial sediments Lake TimiskamingGeological Survey of Canada Open File, No. 4492, 1 CD $ 26.00Ontario, Lake TimiskamingGeomorphology, geochemistry
DS200412-1261
2003
McClenaghan, B.McClenaghan, B.The Seed and Triple B kimberlites and associated glacial sediments Lake Timiskaming area, Ontario.Geological Survey of Canada Open File, No. 4492, 1 CD $ 26.00Canada, Ontario, Lake TemiskamingGeomorphology, geochemistry
DS200512-0924
2004
McClenaghan, B.Sader, J.A., Leybourne, M.I., McClenaghan, B., Sherwood Lollar, B., Hamilton, S.M.Low T serpentinization and the production of hydrogen and methane gas in kimberlites in northeastern Ontario, Canada.Geological Society of America South Central Meeting ABSTRACTS, Vol. 36, 1, p. 28.Canada, Ontario, Kirkland Lake, Lake TemiskamingA4, B30, C14, groundwater interaction
DS1991-1096
1991
McClenaghan, B.M.McClenaghan, B.M.Geochemistry of tills from the Black River Matheson (BRiM) sonic overburden drilling program and implications for explorationOntario Geological Survey Open File, No. 5800, 263p. Kimberlite pp. 71-77; pp. 226-229OntarioGeochemistry, Heavy minerals, diopside, ilmenite
DS1991-1097
1991
McClenaghan, B.M.McClenaghan, B.M.Geochemistry of tills from the Black-River Matheson (BRiM) sonic overburden drilling program and implications for explorationOntario Geological Survey Open File, No. 5800, 263p. Only portion in fileOntarioGeochemistry, Tills Overburden drilling
DS1990-1001
1990
McClenaghan, M.B.McClenaghan, M.B., Wyatt, P.H.Summary of overburden and bedrock trace element dat a from the Kirkland Lake initiatives program (KLIP) reconnaissance till sampling ProgramOntario Geological Survey Open File, No. 5737, 470pOntarioKirkland Lake, Soil sampling
DS1992-1026
1992
McClenaghan, M.B.McClenaghan, M.B.Surface till geochemistry and implications for exploration, Black River-Matheson Area, northeastern Ontario.The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Exploration Mining Geology, Vol. 1, No. 4, October pp. 327-337.OntarioGeochemistry, General - not specific to diamonds
DS1992-1027
1992
McClenaghan, M.B.McClenaghan, M.B., DiLabio, R.N.W.Drift prospecting for diamonds and overburden drill hole compilation in the Kirkland Lake and Timmins areas.Ontario Geological Survey, Ontario Mines and Minerals Symposium held Dec., Poster abstract only, p. 45.OntarioGeochemistry, Drilling
DS1992-1028
1992
McClenaghan, M.B.McClenaghan, M.B., Lavin, O.P., Nichol. I., Shaw, J.Geochemistry and clast lithology as an aid to till classification, Matheson, Ontario, CanadaJournal of Geochemical Exploration, Vol. 42, No. 2-3, February pp. 237-260OntarioGeochemistry, Till classification, -Not specific to kimberlite mineralogy -mentions
DS1993-0989
1993
McClenaghan, M.B.McClenaghan, M.B.Location of known kimberlitic bedrock, float and indicator minerals in drift in the Kirkland Lake area, OntarioGeological Survey of Canada, Open file, No. 2636, 1 mapOntarioKimberlites, Open File -ad
DS1993-0990
1993
McClenaghan, M.B.McClenaghan, M.B.Location of known kimberlitic bedrock float and indicator minerals in driftin the Kirkland Lake area.Geological Survey Canada Open File, OF No. 2636, 1 map in colour coded 1: 100, 000 $ 17.25Ontario, Kirkland LakeKimberlite locations, Map
DS1993-0991
1993
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.M., Stirling, J.A.R., Pringle, G.Chemistry of kimberlitic indicator minerals in drift from the Kirkland Lakearea, northeastern OntarioGeological Survey of Canada, $ 57.00 and $ 15.00 and 15.00, Open File, No. 2761, 375p. 1 disc. 1 map 1: 200, 000OntarioGeochemistry, Indicator minerals
DS1993-0992
1993
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, Stirling, Pringle et al.Chemistry of kimberlite indicator minerals in drift from the Kirkland Lakearea, northeastern Ontario.Geological Survey of Canada (GSC) Open File, No. 2761, 375p.Ontario, Kirkland LakeGeochemistry, Geomorphology
DS1994-0085
1994
McClenaghan, M.B.Averril, S.A., McClenaghan, M.B.Behaviour of kimberlite indicator minerals in glacial sediments. C14 And diamond Lake kimberlite pipes, Kirkland Lake Ontario.Geological Survey of Canada Open File, No. 2819OntarioGeochemistry, Geomorphology
DS1994-1137
1994
McClenaghan, M.B.McClenaghan, M.B.Till geochemistry in areas of thick drift and its application to goldexploration, Matheson area, northeastern OntarioExploration and Mining Geology, Vol. 3, No. 1, January pp. 17-30OntarioGeochemistry, gold, Geomorphology -till
DS1994-1138
1994
McClenaghan, M.B.McClenaghan, M.B.Exploration for kimberlites using drift prospecting, Kirkland Lake regionHandout Prospectors and Developers Association of Canada (PDAC) meeting March 1994, 11p.OntarioKirkland Lake, Geochemistry
DS1994-1139
1994
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.Glacial dispersal of kimberlitic indicator minerals, Kirkland Lake, Ontario.Geological Survey of Canada Open Forum January 17-19th. Abstracts only, p. 27.OntarioGeomorphology, Indicator minerals
DS1995-1200
1995
McClenaghan, M.B.McClenaghan, M.B., Dilabio, R.N.W.Overburden drill hole compilation, Timmins OntarioGeological Survey of Canada Open File, No. 3086, $ 78.00 plus discs $ 39.00OntarioGeochemistry -overburden drill samples
DS1995-1201
1995
McClenaghan, M.B.McClenaghan, M.B., Dunn, C.E.Biogeochemical survey over kimberlites in the Kirkland Lake area northeastern Ontario.Geological Survey of Canada, Open File 3005Ontario, Kirkland LakeGeochemistry -biogeochemistry, Kimberlites
DS1995-1202
1995
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.M.Till mineralogy and geochemistry of the Buffonta kimberlite dike, Kirkland Lake Ontario.Geological Survey of Canada, Open File 3007Ontario, Kirkland LakeGeochemistry -till, Deposit -Buffonta
DS1995-1203
1995
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.M., Crabtree, D.Mineralogy and geochemistry of till and soil overlying the Buffonta kimberlite dyke area, Kirkland Lake.Geological Survey of Canada Open File, No. 3007, $ 31.69OntarioGeochemistry, Deposit -Buffonta
DS1995-1204
1995
McClenaghan, M.B.McClenaghan, M.B., Veillette, J.J., Dilabio, R.N.W.Ice flow indicators in the Timmins and Kirkland Lake areas, northeasternOntario.Geological Survey of Canada Open File, No. 3014, 1 map colour and i disk $ 40.00OntarioGeomorphology, Ice flow Kirkland Lake area
DS1995-1981
1995
McClenaghan, M.B.Veillette, J.J., McClenaghan, M.B.The sequence of ice flow in Abitibi-Timiskaming: implications for mineral exploration and dispersal...Geological Survey of Canada, Open file, No. 3033, $ 27.00 1 map 1:500, 000Quebec, OntarioMap, Geomorphology -ice flow
DS1996-0394
1996
McClenaghan, M.B.Dunn, C.E., McClenaghan, M.B.Biogeochemical studies of kimberlitesGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 219-223.Saskatchewan, OntarioBiogeochemistry, Mineral sampling -indicators
DS1996-0718
1996
McClenaghan, M.B.Katsube, T.J., McClenaghan, M.B., Scromeda, N.Petrophysical characteristics of diatreme facies kimberlites from KirklandLake, Ontario.Geological Survey of Canada (GSC) Paper, No.1996-E, pp. 171-8.Ontario, Kirkland LakePetrology
DS1996-0915
1996
McClenaghan, M.B.McClenaghan, M.B.Geochemical and mineralogical signatures of kimberlite in glacial drift, Kirkland Lake, Ontario.Geological Survey of Canada Colloquium, Jan. 22-24th., Poster display onlyOntarioExploration, Geomorphology, geochemistry
DS1996-0916
1996
McClenaghan, M.B.McClenaghan, M.B.Geochemistry and indicator mineralogy of drift over kimberlite, Kirkland Lake area.Geological Survey of Canada, LeCheminant ed, OF 3228, pp. 213-218.OntarioGeochemistry, Mineral sampling -indicators
DS1996-0917
1996
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Schultz, D.J., et al.Mineralogy and chemistry of the B30 kimberlite and overlying glacialsediments, Kirkland Lake, Ontario.Geological Survey of Canada Open File, No. 3295, 245p. discette $ 60.00OntarioMineralogy, geochemistry, Deposit -B30 kimberlite project
DS1997-0573
1997
McClenaghan, M.B.Katsube, T.J., Connell, S., McClenaghan, M.B., ArmstrongPetrophysical characteristics of limestone xenoliths in kimberlites from Kirkland Lake, Ontario.Geological Survey of Canada (GSC) Paper, No.1997-E, pp. 45-57.Ontario, Kirkland LakePetrology
DS1997-0753
1997
McClenaghan, M.B.McClenaghan, M.B., Thorleifson, L.H., DiLabio, R.N.W.Till geochemical and indicator mineral methods in mineral explorationExploration 97, Proceedings, pp. 233-248.Northwest Territories, OntarioGeochemistry, Geomorphology, Glacial
DS1998-0739
1998
McClenaghan, M.B.Kerr, D.E., Dredge, L.A., McClenaghan, M.B.Kimberlite indicator minerals in till, Lac de Gras area, NorthwestTerritories.Explore, No. 100, Aug. pp. 1, 3-6, 8-11.Northwest TerritoriesGeochemistry, till, Lac de Gras area
DS1998-0974
1998
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Schultze, D.J.Mineralogy and geochemistry of the Diamond Lake kimberlite and associate desker sediments, KirklandGeological Survey of Canada, Open File, 3576 approx. $ 200.00Ontario, Kirkland LakeMineralogy, geochemistry, Deposit - Diamond Lake
DS1999-0455
1999
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.A.Mineralogy and geochemistry of the Peddie kimberlite pipe and overlying glacial sediments New Liskeard OntarioAssocation of Exploration Geologists (AEG) 19th. Symposium Program Abstracts, p. 87. AbstractOntarioGeochemistry, Deposit - Peddie
DS1999-0456
1999
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.A., Kjarsgaard, I.M.Mineralogy and chemistry of the Peddie kimberlite and associated glacialsediment, Lake Timiskaming.Geological Survey of Canada (GSC) Open File, No. 3775, 190p. 1 disk. $ 72.28OntarioGeochemistry, Deposit - Peddie
DS1999-0457
1999
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Stirling et al.Mineralogy and geochemistry of the C14 kimberlite and associated glacialsediments, Kirkland Lake Ontario.Geological Survey of Canada Open file, No. 3719, 147p. $ 53.00OntarioGeochemistry - data, Deposit - C14
DS2000-0641
2000
McClenaghan, M.B.McClenaghan, M.B., Thorleifson, L.H., Dilabio, R.N.W.Till geochemical and indicator mineral methods in mineral exploration.pp. 157-159 on diamondJournal of Geochem. Exp., Vol. 69-70, pp.145-66.Finland, Canada, Fennoscandia, Northwest TerritoriesGeochemistry - diamonds, Glacial, geomorphology
DS2000-0642
2000
McClenaghan, M.B.McClenaghan, M.B., Ward, B.C., Kjarsgaard, B.A.Indicator mineral and till geochemical dispersal associated with the Ranch Lake kimberlite, Lac de GrasGeological Survey of Canada (GSC) Open File, No. 3924, 198p.Northwest TerritoriesGeochemistry, Deposit - Ranch Lake
DS2001-0747
2001
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.A.Indicator mineral and geochemical methods for diamond exploration in glaciated terrain in Canada.Drift Exploration in Glaciated Terrain, Geological Society of London, Geological Society of London No. 185, pp. 83-123.CanadaGeochemistry - till, Sampling
DS2001-0748
2001
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A.Reconnaisance scale till survey in New Liskard Temagami region: kimberlite indicator minerals and geochemistry.Geological Survey of Canada (GSC) Open File, No. 4086, 98p. CD $ 30.00Ontario, Kirkland LakeGeochemistry - sampling
DS2001-0749
2001
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaardm I.M., Kjarsgaard, B.A.Reconnaissance scale till survey New Liskard Temagami region. Kimberlite indicator minerals and geochemistryGeological Survey of Canada (GSC) Open File, No. 4086, 98p. $ 22.00OntarioGeochemistry
DS2001-0750
2001
McClenaghan, M.B.McClenaghan, M.B., Veillette, J.J.Ice flow indicators for the New Liskard - Temagami area, Ontario. NTS 31L,M, 41 I-P.Geological Survey of Canada (GSC) Open File, No. 3385, 1 map 1: 100,000 $ 20.Ontario, Kirkland LakeGeochemistry - sampling, Geomorphology
DS2001-0761
2001
McClenaghan, M.B.McMartin, I., McClenaghan, M.B.Till geochemistry and sampling techniques in glaciated shield terrain: a reviewDrift Exploration in Glaciated Terrain, Geological Society of London, Geological Society of London No. 185, pp. 19-43.Canada, Ontario, FennoscandiaGeochemistry - till, Sampling
DS2002-0641
2002
McClenaghan, M.B.Hamilton, S.M., Cameron, S.C.M., McClenaghan, M.B., Hall, G.E.M.Thick overburden geochemical methods: studies over volcanogenic massive sulphideOntario Geological Survey Open File, Summary of Field Work, No. 6100, pp. 27-1-17.Ontario, TimminsGeochemistry
DS2002-1027
2002
McClenaghan, M.B.McClenaghan, M.B.Indicator mineral and till geochemical methods for kimberlite exploration in glaciated terrain.C.i.m. Bulletin, Vol. 95, No. 1061, May, pp. 79-84.Northwest Territories, OntarioGeochemistry - indicator minerals, kimberlites, Techniques - sampling
DS2002-1028
2002
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.A., Kjarsgaard, I.M.Indicator mineral content and geochemistry of till around the Peddie kimberlite Lake Tamiskaming, Ontario.Geological Survey of Canada Open file, No.4262, 140p. 1 cd $ 23.Ontario, TimiskamingGeochemistry, Deposit - Peddie
DS2002-1029
2002
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjardsgaard, B.A., Heaman, L.M.Mineralogy of kimberlite boulders from eskers in the Lake Timiskaming and Kirkland Lake areas, northeastern Ontario.Geological Survey of Canada Open File, No.4361, 1 CD $ 26.OntarioGeochemistry - database CD
DS2002-1030
2002
McClenaghan, M.B.McClenaghan, M.B., Ward, B.C., Kjarsgaard, B.A., Kerr, D.E., Dredge, L.A.Indicator minerals and till geochemical dispersal patterns associated with the RanchGeochemistry, Exploration, Environment, Analysis, Vol. 2, No. 4, pp. 299-319.Northwest TerritoriesGeochemistry, Deposit - Ranch Lake
DS2003-0723
2003
McClenaghan, M.B.Kjarsgaard, I.M., McClenaghan, M.B., Kjarsgaard, B.A., Heaman, L.Mineralogy of the kimberlite boulders from eskers in the Kirkland Lake and Lake8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractOntarioGeochemistry, geomorphology
DS2003-0903
2003
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A.Mineralogy of the McLean kimberlite and associated glacial sediments, LakeGeological Survey of Canada Open File, No. 1762, 1 CD $ 20.00OntarioGeomorphology, Deposit - McLean
DS2003-0904
2003
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, B.A.The Seed and Triple B kimberlites and associated glacial sediments, Lake TimiskamingGsc Open File 4492, 1 CD-ROM, cost CDN $20.00Ontario20-page report on the geology and mineralogy of Lake Timiskaming
DS2003-0905
2003
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A.Mineralogy of McLean kimberlite and associated glacial sediments, Lake TimiskamingGeological Survey of Canada Open File, No. 1762, 1 CD, 33p. $ 26.00OntarioGeomorphology, geochemistry
DS2003-0906
2003
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A., Sobie, P.A.Application of surficial exploration methods in the Lake Timiskaming kimberlite field8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractOntarioGeochemistry, geomorphology
DS2003-0907
2003
McClenaghan, M.B.McClenaghan, M.B., Ward, B.C., Kjarsgaard, I.M., et al.Indicator minerals and till geochemical dispersal patterns associated with the RanchGeochemistry - Exploration, Environment, Analysis, Vol. 2, part 4, pp. 299-320Northwest Territorieskimberlite indicator minerals, till geochemistry, Ranch Lake kimberlite
DS2003-1203
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.I., McClenaghan, M.B., Hamilton, S.M.Geochemistry of groundwater from Jurassic kimberlites in the Kirkland Lake and LakeGeological Survey of Canada Open File, No. 4515, 1 CD 26p. $ 26.00Ontario, Kirkland LakeGeochemistry
DS2003-1204
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.I., McClenaghan, M.B., Hamilton, S.M., RobertsonGroundwater interaction with kimberlites - a geochemical investigation in northeasternExplore ( AEG Newsletter), No. 118, January pp. 1-4.Ontario, Kirkland LakeGeochemistry, Analytical methods and results
DS2003-1205
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.I., McClenaghan, M.B., Hamilton, S.M., RobertsonField procedures and results of groundwater sampling in kimberlite from drillholes in theGeological Survey of Canada Current Research, 9p.Ontario, Kirkland LakeSampling - geomorphology
DS2003-1206
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.L., McClenaghan, M.B., Hamilton, S.M., RobertsonKimberlite exploration using aqueous geochemistry - a new exploration methodGeological Association of Canada Annual Meeting, Abstract onlyGlobalTechniues - geochemistry
DS200412-1012
2003
McClenaghan, M.B.Kjarsgaard, I.M., McClenaghan, M.B., Kjarsgaard, B.A., Heaman, L.Mineralogy of the kimberlite boulders from eskers in the Kirkland Lake and Lake Timiskaming areas, northeastern Ontario, Canada.8 IKC Program, Session 8, POSTER abstractCanada, OntarioDiamond exploration Geochemistry, geomorphology
DS200412-1013
2004
McClenaghan, M.B.Kjarsgaard, I.M., McClenaghan, M.B., Kjarsgaard, B.A., Heaman, L.M.Indicator mineralogy of kimberlite boulders from eskers in the Kirkland Lake and Lake Timiskaming areas, Ontario, Canada.Lithos, Vol. 77, 1-4, Sept. pp. 705-731.Canada, Ontario, Kirkland LakeMunro, Misema River eskers, Sharp lake, geomorphology
DS200412-1262
2003
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A.Mineralogy of McLean kimberlite and associated glacial sediments, Lake Timiskaming Ontario.Geological Survey of Canada Open File, No. 1762, 1 CD, 33p. $ 26.00Canada, OntarioGeomorphology, geochemistry
DS200412-1263
2003
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A., Sobie, P.A.Application of surficial exploration methods in the Lake Timiskaming kimberlite field, Canada.8 IKC Program, Session 8, POSTER abstractCanada, OntarioDiamond exploration Geochemistry, geomorphology
DS200412-1707
2004
McClenaghan, M.B.Russell, H.A.J., McClenaghan, M.B., Boucher, D., Sobie, P.Kimberlite indicator minerals distribution in eskers, Lake Timiskaming kimberlite field, Ontario and Quebec: preliminary resultsGeological Association of Canada Abstract Volume, May 12-14, SS14-03 p. 262.abstractCanada, Ontario, Lake TemiskamingGeochemistry, geomorphology
DS200412-1717
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.I., McClenaghan, M.B., Hamilton, S.M.Geochemistry of groundwater from Jurassic kimberlites in the Kirkland Lake and Lake Timiskaming kimberlite fields northeastern OGeological Survey of Canada Open File, No. 4515, 1 CD 26p. $ 26.00Canada, Ontario, Kirkland LakeGeochemistry
DS200412-1718
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.I., McClenaghan, M.B., Hamilton, S.M., Robertson, K.Field procedures and results of groundwater sampling in kimberlite from drillholes in the Kirkland Lake and Lake Temiskaming areGeological Survey of Canada Current Research, 9p.Canada, Ontario, Kirkland LakeSampling - geomorphology
DS200412-1719
2003
McClenaghan, M.B.Sader, J.A., Leybourne, M.L., McClenaghan, M.B., Hamilton, S.M., Robertson, K.Kimberlite exploration using aqueous geochemistry - a new exploration method.Geological Association of Canada Annual Meeting, Abstract onlyTechnologyTechniues - geochemistry
DS200512-0701
2004
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A.Kimberlite indicator mineral chemistry and till geochemistry around the Seed and Triple B kimberlites, Lake Timiskaming Ontario.Geological Survey of Canada Open File, No. 4822, 31p. 1 CD $ 26.Canada, Ontario, Lake TemiskamingGeochemistry
DS200512-0702
2005
McClenaghan, M.B.McClenaghan, M.B., Veilette, J.J.Surficial geology: ice flow indicators for the New Liskeard Temagami area, Ontario.Geological Survey of Canada Open File, No. 3385, 1 cd $ 25.Canada, OntarioGeomorphology
DS200612-0888
2006
McClenaghan, M.B.McClenaghan, M.B., Hamilton, S.M., Hall, G.E.M., Burt, A.K., Kjarsgaard, B.A.Selective leach geochemistry of soils overlying the 95-2, B30 and A4 kimberlites, northeast Ontario.Geological Survey of Canada Open File, OF 5069, 28p. $ 9.00Canada, OntarioGeochemistry
DS200712-0704
2006
McClenaghan, M.B.McClenaghan, M.B., Kjarsgaard, I.M., Kjarsgaard, B.A., Russell, H.A.J.Indicator mineralogy of kimberlite boulders and sand samples from the Lac Baby and Sharp Lake eskers, Lake Timiskaming field, western Quebec and northeast OntarioGeological Survey of Canada Open File, No. 5050, 21p.Canada, Quebec, OntarioGeochemistry, geomorphology
DS200712-0924
2007
McClenaghan, M.B.Sader, J.A., Leybourne, M.I., McClenaghan, M.B., Hamilton, S.Low temperature serpentinization processes and kimberlite groundwater signature Kirkland Lake and Lake Timiskaming kimberlite fields: implications diamond exploration.Geochemistry: Exploration, Environment, Analysis, Vol. 7, 1, pp. 3-21.Canada, Ontario, Kirkland Lake, TimiskamingGeochemistry - diamond exploration
DS200912-0487
2009
McClenaghan, M.B.McClenaghan, M.B., Gauvreau, D., Kjarsgaard, B.A.Mineral chemistry database for kimberlite surficial sediments and kimberlite boulders from Lake Timiskaming and Kirkland Lake kimberlite fields.Geological Survey of Canada Open File, No. 5833, $7.00 CDCanada, Ontario, QuebecGeochemistry
DS201012-0569
2010
McClenaghan, M.B.Paulen, R.C., Adcock, S.W., Spirito, W.A., Chorlton, L.B., McClenaghan, M.B., Oviatt, Budulan, RobinsonsInnovative methods to search, download and display indicator mineral data: a new Tri-Territorial Indicator Mineral Database.38th. Geoscience Forum Northwest Territories, Abstract pp. 75-76.Canada, Northwest TerritoriesGEM database
DS201201-0856
2011
McClenaghan, M.B.McClenaghan, M.B.Overview of common processing methods for recovery of indicator minerals from sediment and bedrock in mineral exploration.Geochemistry, Exploration, Environment, Analysis, Vol. 11, 4, Nov. pp. 265-278.TechnologyGeochemistry - review includes diamonds
DS201201-0857
2011
McClenaghan, M.B.McClenaghan, M.B., Cabri, L.J.Review of gold and platinum group elements (PGE) indicator minerals methods for surficial sediment sampling.Geochemistry, Exploration, Environment, Analysis, Vol. 11, 4, Nov. pp. 251-263.TechnologyGeochemistry - review not specific to diamonds
DS201312-0354
2013
McClenaghan, M.B.Hall, G.EM., McClenaghan, M.B.Field portable XRF in exploration and mining.GSC Open file 7374 Ftp2.cits.rncan.gc.ca, pp. 75-85.TechnologyXRF
DS201312-0689
2013
McClenaghan, M.B.Paulen, R.C., McClenaghan, M.B.New frontiers for exploration in glaciated terrain.GSC Open file 7374 Ftp2.cits.rncan.gc.ca, 85p.CanadaShort Course notes - individual papers cited under authors
DS201312-0712
2013
McClenaghan, M.B.Plouffe, A., McClenaghan, M.B., Paulen, R.C., McMartin, I., Campbell, J.E., Spirito, W.A.Quality assurance and quality control measures applied to indicator mineral studies at the Geological Survey of Canada.GSC Open file 7374 Ftp2.cits.rncan.gc.ca, pp. 13-20.CanadaQuality controls
DS201412-0567
2013
McClenaghan, M.B.McClenaghan, M.B., Plouffe, A., McMartin, I., Campbell, J.E., Spirito, W.A., Paulen, R.C., Garrett, R.G., Hall, G.E.M.Till sampling and geochemical analytical protocols used by the Geological Survey of Canada.Geochemistry: Exploration, Environment, Analysis, Vol. 13, pp. 285-301.TechnologySampling
DS201412-0693
2013
McClenaghan, M.B.Plouffe, A., McClenaghan, M.B., Paulen, R.C., McMartin, I., Campbell, J.E., Spirito, W.A.Processing of glacial sediments for the recovery of indicator minerals: protocols used at the Geological Survey of Canada.Geochemistry: Exploration, Environment, Analysis, Vol. 13, pp. 303-316.TechnologySampling
DS201604-0610
2016
McClenaghan, M.B.Hall, E.M.G., McClenaghan, M.B., Page, L.Application of portable XRF to the direct analysis of till samples from various deposit types in Canada.Geochemistry, Exploration, Environment, Analysis, Vol. 16, pp. 62-84.Canada, Northwest TerritoriesKimberlite - Triple B mentioned

Abstract: In this study, results by direct portable XRF (‘pXRF’) on unsieved till samples were compared with those by established laboratory methods (aqua regia or fusion ICP-MS and ICP-ES) on the <0.063-mm fraction to determine if the application of direct pXRF in the field would serve as an acceptable guide for immediate follow-up work. Four test sites in Canada were chosen: the Halfmile Lake Cu-Pb-Zn VMS deposit; the intrusion-hosted W-Mo Sisson deposit; a Pb-Zn Mississippi Valley-type (MVT) deposit in the Pine Point district; and the Triple B kimberlite. Unsieved till samples from the GSC archive collection were used for this study and included samples from background areas, immediately overlying, and at various distances down-ice of each deposit. Ziploc® and Whirl-Pak® bags that were used to contain the samples in the field were tested for their properties of X-ray attenuation and contamination. In general, the performance of pXRF in the four test areas was very good where concentrations of elements of interest (indicator or pathfinder elements) were substantially above detection limits by this technique (in the low ppm range for many elements). The following elements, shown to be useful indicator elements (important constituents of the ore/commodity) or pathfinder elements (those associated with the commodity elements) by the established methodology, showed similar patterns by pXRF on the unsieved material: Zn, Cu, Pb, and As at Halfmile Lake; W, Mo, Cu, Zn, Pb, and As at the Sisson deposit; Zn, Pb, and Fe at Pine Point; and Ca, Sr, Cr, and Ni at Triple B. Pathfinder elements whose concentrations were too low for determination by pXRF include: Ag and Sb at Halfmile Lake; Ag and Cd at Sisson; Cd, S, and Se at Pine Point; and Co, Mg, P, U, and Th at Triple B. The high background for Bi by pXRF, equivalent to c. 50?ppm, and its noisy signal precluded its use at Halfmile Lake and Sisson. Elements which tended to show poor precision (three analyses each sample) by pXRF in some samples due to sample heterogeneity include Sn, V, and W. Mercury was erroneously reported for the majority of samples in the low ppm range by pXRF whereas its concentration in fact was in the low ppb range. Several Pb-, Zn- (c. 1% Pb, Zn) and Fe-rich (up to 16% Fe) samples demonstrated spectral interferences by: Pb on As, Th and Se; Zn on Cu; and Fe on Co. Results for six till samples analysed in Ziploc® and Whirl-Pak® bags showed that Ziploc® absorbs fewer low-energy photons and hence is preferable for determining light elements such as Si, K and Ca.
DS201611-2129
2015
McClenaghan, M.B.Paulen, R.C., McClenaghan, M.B., Trenhaile, A.Late Wisconsin ice-flow history in the Buffalo Head Hills kimberlite field, north-central Alberta.Canadian Journal of Earth Sciences, Vol. 52, 1, pp. 51-67.Canada, AlbertaDeposit - Buffalo Head Hills

Abstract: Ice flow of the last glaciation in the Buffalo Head Hills kimberlite field of northern Alberta is reconstructed from landform interpretations and clast orientations for the purpose of aiding kimberlite exploration in the region. The paucity of bedrock outcrop and the absence of preserved striae and other erosional ice-flow indicators on the soft Cretaceous marine sediments inhibit detailed interpretations on glacial flow chronology. Poorly developed bedrock drumlins on the Buffalo Head Hills and erosional ice-flow indicators preserved on the kimberlite outcrops indicate southwestward ice flow during the maximum extent of ice during the last glaciation. During the deglaciation of northern Alberta, later phases of ice flow were controlled by lobes of surging ice, which surged into proglacial lakes. West of the Buffalo Head Hills, the maximum phase of southwest flow was followed by southeastward ice movement of the Peace River ice lobe. Similarly, east of the Buffalo Head Hills, the maximum phase of ice flow was superceded by a south-southwest ice advance of the Wasbasca ice lobe.
DS201911-2546
2019
McClenaghan, M.B.McClenaghan, M.B., Paulen, R.C., Kjarsgaard, I.M.Rare metal indicator minerals in bedrock and till at the Strange Lake peralkaline complex, Quebec and Labrador, Canada.Canadian Journal of Earth Science, Vol. 56, pp. 957-969.Canada, Quebec, LabradorREE

Abstract: A study of rare metal indicator minerals and glacial dispersal was carried out at the Strange Lake Zr?-?Y?-?heavy rare earth element deposit in northern Quebec and Labrador, Canada. The heavy mineral (>3.2 specific gravity) and mid-density (3.0-3.2 specific gravity) nonferromagnetic fractions of mineralized bedrock from the deposit and till up to 50 km down ice of the deposit were examined to determine the potential of using rare earth element and high fileld strength element indicator minerals for exploration. The deposit contains oxide, silicate, phosphate, and carbonate indicator minerals, some of which (cerianite, uraninite, fluorapatite, rhabdophane, thorianite, danburite, and aeschynite) have not been reported in previous bedrock studies of Strange Lake. Indicator minerals that could be useful in the exploration for similar deposits include Zr silicates (zircon, secondary gittinsite (CaZrSi2O7), and other hydrated Zr±Y±Ca silicates), pyrochlore ((Na,Ca)2Nb2O6(OH,F)), and thorite (Th(SiO4))/thorianite (ThO2) as well as rare earth element minerals monazite ((La,Ce,Y,Th)PO4), chevkinite ((Ce,La,Ca,Th)4(Fe,Mg)2(Ti,Fe)3Si4O22), parisite (Ca(Ce,La)2(CO3)3F2), bastnaesite (Ce(CO3)F), kainosite (Ca2(Y,Ce)2Si4O12(CO3)•H2O), and allanite ((Ce,Ca,Y)2(Al,Fe)3(SiO4)3(OH)). Rare metal indicator minerals can be added to the expanding list of indicator minerals that can be recovered from surficial sediments and used to explore for a broad range of deposit types and commodities that already include diamonds and precious, base, and strategic metals.
DS202001-0027
2019
McClenaghan, M.B.Lougheed, H.D., McClenaghan, M.B., Layton-Matthews, D., Leybourne, M.I.Evaluation of single use nylon screened sieves for use with fine grained sediment samples.Geological Survey of Canada, Open File 8613, 13p. PdfGlobalsieves
DS202111-1782
2021
McClenaghan, M.B.Sader, J.A., Harrison, A.L., McClenaghan, M.B., Hamilton, S.M., Clark, I.D.Sherwood Lollar, B., Leybourne, M.I.Generation of high-pH groundwaters and H2 gas by groundwater-kimberlite interaction, northeastern Ontario.The Canadian Mineralogist, Vol. 59, pp. 1261-1276. doi:10.3749/canmin.2000048 pdfCanada, Ontariodeposit - Kirkland Lake

Abstract: We report new isotopic data for H2 and CH4 gases and Sr for groundwater collected from Jurassic Kirkland Lake kimberlites in northern Ontario, Canada. Groundwaters interacting with kimberlites have elevated pH (up to 12.4), are reducing (Eh as low as the H2-H2O couple), are dominated by OH? alkalinity, and have non-radiogenic (mantle) 87Sr/86Sr values (?0.706-0.707). Most significantly, the highest pH groundwaters have low Mg, high K/Mg, and are associated with abundant reduced gases (H2 ± CH4). Open system conditions favor higher dissolved inorganic carbon and CH4 production, whereas under closed system conditions low DIC, elevated OH? alkalinity, and H2 production are enhanced. Hydrogen gas is isotopically depleted (?2HH2 = ?771 to ?801‰), which, combined with ?2HH2O, yields geothermometry temperatures of serpentinization of 5-25 °C. Deviation of H2-rich groundwaters (by up to 10‰) from the meteoric water line is consistent with Rayleigh fractionation during reduction of water to H2. Methane is characterized by ?13CCH4 = ?35.8 to ?68‰ and ?2HCH4 = ?434‰. The origin of CH4 is inconclusive and there is evidence to support both biogenic and abiogenic origins. The modeled groundwater-kimberlite reactions and production of elevated concentrations of H2 gas suggest uses for diamond-production tailings, as a source of H2 for fuel cells and as a carbon sink.
DS1987-0566
1987
McClenaghan, M.P.Parker, A.J., Rickwood, P.C., Baillie, P.W., McClenaghan, M.P.Mafic dyke swarms of Australiain: Mafic dyke swarms, Editors, Halls, H.C., Fahrig, W.F. Geological, Special Paper 34, pp. 401-417AustraliaKimberley Basin, Canning Basin p. 408, southeast Victoria p. 4, Kimberlite, Lamproite
DS1994-1140
1994
McClenaghan, M.P.McClenaghan, M.P., Seymour, D.B., Villa, I.M.Lamprophyre dike suites from western Tasmania, their radiometric dating And the age of thrust faulting in the Point Hibbs area.Australian Journal of Earth Sciences, Vol. 41, No. 1, February pp. 47-54.Australia, TasmaniaMinettes, Lamprophyres
DS1985-0040
1985
MccleneaghanBaker, C.L., Steele, K.G., MccleneaghanReconnaissance till sampling program Matheson Lake Abitibi areaCochranedistrictOntario Geological Survey miscellaneous Paper, No. 126, pp. 329-333OntarioSampling, Geochemistry
DS200612-0889
2006
McClennan, S.M.McClennan, S.M., Taylor, S.R., Hemming, S.R.Composition, differentiation, and evolution of continental crust: constraints from sedimentary rocks and heat flow.Evolution and differentiation of Continental Crust, ed. Brown, M., Rushmer, T., Cambridge Univ. Press, Chapter 2, pp. 92-134.MantleMineral chemistry
DS200912-0285
2009
McClintock, M.Harvey, S., Kjarsgaard, McClintock, M., Shimell, M., Fourie, L., Du Plessis, P., Read, G.Geology and evaluation strategy of the Star and Orion South kimberlites, Fort a la Corne, Canada.Lithos, In press availableCanada, SaskatchewanDeposit - Star, Orion
DS200912-0384
2009
McClintock, M.Kjarsgaard, B.A., Harvey, S., McClintock, M., Zonneveld, J.P., Du Plessis, P., McNeil, D., Heaman, L.Geology of the Orion South kimberlite, Fort a la Corne, Canada.Lithos, In press - available formatted 15p.Canada, SaskatchewanDeposit - Orion South
DS200912-0488
2009
McClintock, M.McClintock, M., Ross, P-S., White, J.D.L.The importance of the transport system in shaping the growth and form of kimberlite volcanoes.Lithos, In press available 8p.MantlePhreatomagmatism
DS200912-0643
2009
McClintock, M.Ross, P., White, J.D., Lorenz, V., Zimanowski, B., Boettner, R., McClintock, M.Why lower diatremes in kimberlitic and non-kimberlitic systems are non-stratified, homogenized, and contain steep internal contacts: episodic burst and debris jets.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyMantleBoundary
DS2001-1233
2001
McClintock, M.K.White, J.D.L., McClintock, M.K.Immense vent complex marks flood basalt eruption in a wet failed rift: Coombs Hills Antartica.Geology, Vol. 29, No. 10, Oct. pp. 935-8.AntarcticaDiatremes, volcanic vebts, phreatomagmatic, rifting
DS1960-1141
1969
Mccloughan, C.H.Kanasewich, E.R., Clowes, R.M., Mccloughan, C.H.A Buried Precambrian Rift in Western CanadaTectonophysics, Vol. 8, pp. 513-27.Alberta, Western CanadaTectonics
DS201012-0625
2010
McClung, C.R.Richards, B., McClung, C.R., Voljoen, F.Characterization of the Kolo kimberlite pipe: constraints on the composition and genesis of the Diamondiferous lithospheric mantle below Kaapvaal.Geological Society of America Abstracts, 1/2p.Africa, LesothoDeposit - Kolo
DS2000-0812
2000
McClureReinitz, I.M., Buerki, P.R., Shigley, J.E., McClureIdentification of HPHT treated yellow to green diamonds. the saturated neon green colour is not only..Gems and Gemology, Vol. 36, No. 2, Summer, pp. 128-37.United States, Russia, SwedenDiamond - GE, Novatek, treated, colour
DS1990-0798
1990
McClure, S.F.Kammerling, R.C., Kane, R.E., Koivula, J.I., McClure, S.F.An investigation of a suite of black diamond jewelryGems and Gemology, Vol. 26, Winter pp. 282-287GlobalDiamond morphology, Black diamond
DS1990-0800
1990
McClure, S.F.Kane, R.E., McClure, S.F., Menzhausen, J.The legendary Dresden green diamondGems and Gemology, Vol. 26, Winter pp. 248-266IndiaHistory, Dresden diamond
DS1994-0869
1994
McClure, S.F.Kammerling, R.C., McClure, S.F., Johnson, M.L., et al.An update on filled diamonds: identification and durabilityGems and Gemology, Vol. 30, Fall pp. 142-177.GlobalDiamond -fracture filled, Diamond markets, industry
DS1995-1205
1995
McClure, S.F.McClure, S.F., Kammerling, R.C.A visual guide to the identification of filled diamondsGems and Gemology, Vol. 31, summer pp. 114-119. plus chart.GlobalDiamond morphology, Diamond -filled
DS1997-0836
1997
McClure, S.F.Nassau, K., McClure, S.F., Elen, S., Shigley, J.E.Synthetic moissanite: a new diamond substituteGems and Gemology, Vol. 33, winter, pp. 260-275.GlobalDiamond synthesis, Moissanite
DS2000-0643
2000
McClure, S.F.McClure, S.F., King, J.M., Koivula, J.J., Moses, T.M.A new lasering technique for diamondGems and Gemology, Vol. 36, No. 2, Summer, pp. 138-46.GlobalDiamond - treatment, laser enhancement
DS2000-0891
2000
McClure, S.F.Shigley, J.F., McClure, S.F., Koivula, J.I., Moses, T.New filling material for diamonds from OVED Diamond Company: a preliminarystudy.Gems and Gemology, Vol. 36, No. 2, Summer, pp. 147-53.GlobalDiamond - treatment
DS200412-1804
2004
McClure, S.F.Shigley, J.E., McClure, S.F., Breeding, C.M., Hsi-tien Shen, A., Muhlmeister, S.M.Lab grown coloured diamonds from Chatham created gems. Identifying characteristics of yellow, blue, green and pink synthetic diaGems & Gemology, Vol. 40, 2, Summer, pp.128-145.ChinaDiamond synthesis
DS200712-0977
2007
McClure, S.F.Shen, A.H., Wang, W., Hall, M.S., Novak, S., McClure, S.F., Shigley, J.E., Moses, T.M.Serenity coated colored diamonds: detection and durability.Gems & Gemology, Vol. 43, 1, Spring pp. 16-34.TechnologyFancy diamonds
DS200912-0693
2009
McClure, S.F.Shigley, J.E., McClure, S.F.Laboratory treated gemstones.Elements, Vol. 5, 3, June pp. 175-178.TechnologyMethodology
DS200912-0785
2009
McClure, S.F.Van der Bogert, C.H., Smith, C.P., Hainschwang, T., McClure, S.F.Gray to blue to violet hydrogen rich diamonds from the Argyle mine, Australia.Gems & Gemology, Vol. 45, 1, Spring pp. 20-37.AustraliaDeposit - Argyle, diamond mineralogy
DS201903-0540
2018
McClure, S.F.Renfro, N.D., Koivula, J.I., Muyal, J., McClure, S.F., Schumacher, K., Shigley, J.E.Inclusions in natural, synthetic, and treated diamonds. Gems & Gemology, Vol. 54, 4, pp. 428-429.Globaldiamond inclusions
DS202003-0349
2019
McClure, S.F.McClure, S.F., Moses, T.M., Shigley, J.E.The geographic origin dilemma.Gems & Gemology, Vol. 55, 4, pp. 457-463.Globalgemstones

Abstract: Welcome to the Winter 2019 edition of Gems & Gemology. This issue is special in that it is devoted exclusively to one timely subject: the determination of geographic origin for specific colored stones. Geographic origin determination is one of the most pressing issues facing the industry—a subject with many facets and complexities that should be addressed if the discussion is to be thorough. As part of GIA’s consumer protection mission of ensuring the public trust in gems and jewelry, our purpose with this issue is to lay out what we know about determining geographic origin and how we arrive at those opinions. These articles will present every aspect of geographic origin as these authors understand it—including full transparency on the approaches and testing methods typically applied in GIA’s gemological laboratories. We intend for this issue to promote healthy and useful discussion and debate—fueled by our collective interest in bringing more understanding and consistency to the reporting of the geographic origin of colored stones.
DS202003-0350
2019
McClure, S.F.McClure, S.F., Moses, T.M., Shigley, J.E.What's next .. Future of geographic origin determination.Gems & Gemology, Vol. 55, 4, p. 682.GlobalGIA

Abstract: GIA’s field gemology program was established in late 2008 to support research on geographic origin determination of colored gemstones. By building and maintaining an extensive collection of gem materials with known origins, GIA’s research scientists have been able to study and analyze rubies, sapphires, emeralds, and other gemstones using the best available reference samples. This has led to improved origin determination services while supporting numerous research and education projects. To date the collection has accumulated during more than 95 field expeditions on six continents and currently includes more than 22,000 samples. GIA’s field gemology efforts require a thorough understanding of the gem trade, including the evolution of gemstone deposits and the development of treatments. It is important to recognize potential new deposits and gemstone enhancement procedures immediately because they can change rapidly and leave a lasting impact on the trade. Field expeditions also involve documenting the mines and local conditions. These factors provide context for the gemstones and are becoming increasingly important in the eyes of the public.
DS202003-0355
2019
McClure, S.F.Palke, A.C., Saeseaw, S., Renfro, N.D., Sun, Z., McClure, S.F.Geographic origin of ruby.Gems & Gemology, Vol. 55, 4, pp. 580-579.Global, Asia, Myanmar, Vietnam, Cambodia, Thailand, Africa, Madagascar, Mozambique, Europe, Afghanistanruby

Abstract: Over the last several decades, geographic origin determination for fine rubies has become increasingly important in the gem trade. In the gemological laboratory, rubies are generally broken down into two groups based on their trace element chemistry: marble-hosted (low-iron) rubies and high-iron rubies. High-iron rubies are usually a straightforward identification based on their inclusions and trace element profiles. Marble-hosted rubies can be more challenging, with some deposits showing overlap in some of their inclusion scenes. But many marblehosted rubies, especially Burmese stones from Mogok and Mong Hsu, can be accurately identified based on their internal features and trace element profiles. This contribution will outline the methods and criteria used at GIA for geographic origin determination for ruby.
DS202003-0359
2019
McClure, S.F.Saeseaw, S., Renfro, N.D., Palke, A.C., Sun, Z., McClure, S.F.Geographic origin of emerald.Gems & Gemology, Vol. 55, 4, pp. 614-647.South America, Colombia, China, Europe, Afghanistan, Africa, Zambiaemerald

Abstract: The gem trade has grown to rely on gemological laboratories to provide origin determination services for emeralds and other fine colored stones. In the laboratory, this is mostly accomplished by careful observations of inclusion characteristics, spectroscopic analysis, and trace element profile measurements by laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS). Inclusions and spectroscopy can often separate Colombian emeralds from other sources (although there is some overlap between Colombian, Afghan, and Chinese [Davdar] emeralds). For non-Colombian emeralds, trace element analysis by LA-ICP-MS is needed in addition to information from the stone’s inclusions. The relative chemical diversity of emeralds from worldwide deposits allows confidence in origin determination in most cases. This contribution outlines the methods and criteria used at GIA for geographic origin determination for emerald.
DS200612-0385
2006
McClusky, S.Fadil, A., Vernant, P., McClusky, S., Reilinger, R., Gomez, F., Ben Sari, D., Mourabit, Feigl, BarazangiActive tectonics of the western Mediterranean: geodetic evidence for rollback of a delaminated subcontinental lithospheric slab beneath the Rif Mountains, Morocco.Geology, Vol. 34, 7, July pp. 529-532.Africa, MoroccoTectonics, continental dynamics
DS200612-1150
2006
McClusky, S.Reilinger, R., McClusky, S., Vernant, P., Lawrence, S., Ergintav, Cakmak, Ozener, Kadirov, Guliev, StepanyanGPS constraints on continental deformation in the Africa Arabia Eurasia continental collision zone and implications for the dynamics of plate interactions.Journal of Geophysical Research, Vol. 111,B5 B05411.AfricaGeodynamics
DS200612-1155
2006
McClusky, S.Relinger, R., McClusky, S., Vernant, P., Lawrence, S.GPS constraints on continental deformation in the Africa-Arabia-Eurasia continental collision zone and implications for the dynamics of plate interactions.Journal of Geophysical Research, Vol. 111, B5, May 31, B05411AfricaTectonics
DS201908-1797
2019
McColl, K.Murri, M., Smith, R.L., McColl, K., Hart, M., Alvaro, M., Jones, A.P., Nemeth, P., Salzmann, C.G., Cora, F., Domeneghetti, M.C., Nestola, F., Sobolev, N.V., Vishnevsky, S.A., Logvinova, A.M., McMillan, P.F.Quantifying hexagonal stacking in diamond. ( lonsdaleite)Nature Scientific Reports, doi.org/10.1038/ s41598-019-46556-3 8p. PdfGlobaldiamond morphology, impact craters

Abstract: Diamond is a material of immense technological importance and an ancient signifier for wealth and societal status. In geology, diamond forms as part of the deep carbon cycle and typically displays a highly ordered cubic crystal structure. Impact diamonds, however, often exhibit structural disorder in the form of complex combinations of cubic and hexagonal stacking motifs. The structural characterization of such diamonds remains a challenge. Here, impact diamonds from the Popigai crater were characterized with a range of techniques. Using the MCDIFFaX approach for analysing X-ray diffraction data, hexagonality indices up to 40% were found. The effects of increasing amounts of hexagonal stacking on the Raman spectra of diamond were investigated computationally and found to be in excellent agreement with trends in the experimental spectra. Electron microscopy revealed nanoscale twinning within the cubic diamond structure. Our analyses lead us to propose a systematic protocol for assigning specific hexagonality attributes to the mineral designated as lonsdaleite among natural and synthetic samples.
DS202011-2054
2020
McColl, K.Murri, M., Smith, R.L., McColl, K., Hart, M., Alvaro, M., Jones, A.P., Nemeth, P., Salzmann, C.G., Cora, F., Domeneghetti, M.C., Nestola, F., Sobolev, N.V., Vishnevsky, S.A., Logvinova, A.M., McMillan, P.F.Quantifying hexagonal stacking in diamond.Nature/scientific reports, 8p. PdfGlobalcrystallography

Abstract: Diamond is a material of immense technological importance and an ancient signifier for wealth and societal status. In geology, diamond forms as part of the deep carbon cycle and typically displays a highly ordered cubic crystal structure. Impact diamonds, however, often exhibit structural disorder in the form of complex combinations of cubic and hexagonal stacking motifs. The structural characterization of such diamonds remains a challenge. Here, impact diamonds from the Popigai crater were characterized with a range of techniques. Using the MCDIFFaX approach for analysing X-ray diffraction data, hexagonality indices up to 40% were found. The effects of increasing amounts of hexagonal stacking on the Raman spectra of diamond were investigated computationally and found to be in excellent agreement with trends in the experimental spectra. Electron microscopy revealed nanoscale twinning within the cubic diamond structure. Our analyses lead us to propose a systematic protocol for assigning specific hexagonality attributes to the mineral designated as lonsdaleite among natural and synthetic samples.
DS202011-2056
2020
McColl, K.Nemeth, P., McColl, K., Garvie, L.A.J., Salzmann, C.Complex nanostructures in diamond. Nature Materials, doi:10.1038/s4 1563-020-0759-8 7p. PdfGlobalmeteorites, synthetics

Abstract: Meteoritic diamonds and synthesized diamond-related materials contain a wide variety of complex nanostructures. This Comment highlights and classifies this structural complexity by a systematic hierarchical approach, and discusses the perspectives on nanostructure and properties engineering of diamond-related materials.
DS202102-0211
2020
McColl, K.Nemeth, P., McColl, K., Smith, R., Murri, M.Diamond-Graphene composite nanostructures.Nano Letters, doi.10.1021/acs/ nanolett.Oc0556 10p. PdfGlobalnanodiamond

Abstract: The search for new nanostructural topologies composed of elemental carbon is driven by technological opportunities as well as the need to understand the structure and evolution of carbon materials formed by planetary shock impact events and in laboratory syntheses. We describe two new families of diamond-graphene (diaphite) phases constructed from layered and bonded sp3 and sp2 nanostructural units and provide a framework for classifying the members of this new class of materials. The nanocomposite structures are identified within both natural impact diamonds and laboratory-shocked samples and possess diffraction features that have previously been assigned to lonsdaleite and postgraphite phases. The diaphite nanocomposites represent a new class of high-performance carbon materials that are predicted to combine the superhard qualities of diamond with high fracture toughness and ductility enabled by the graphitic units and the atomically defined interfaces between the sp3- and sp2-bonded nanodomains.
DS200712-0212
2007
McCombc, J.A.Dahl, P.S., Hamilton, M.A., Wooden, J.L., Foland, K.A., Frei, R., McCombc, J.A., Holm, D.K.2480 Ma mafic magmatism in the northern Black Hills, South Dakota: a new link connecting the Wyoming and Superior Cratons.Canadian Journal of Earth Sciences, Vol. 43, 10, pp. 1579-1600.United States, Wyoming, Canada, AlbertaMagmatism
DS2001-0751
2001
McCombe, D.McCombe, D.New standards of disclosure for mineral projectsThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) ., Vol. 94, No. 1047, Feb. pp. 27-30.CanadaLegal, Laws - regulatory
DS2002-1031
2002
McCombe, D.McCombe, D.The Canadian experience - disclosure standards for mineral projectsAustralian Institute of Mining and Metallurgy, No. 3/2002, pp.13-20.CanadaMineral reserves - definitions, category, Legal - regulations
DS200412-1264
2004
McCombe, D.McCombe, D.National instrument 43-101: what do Canadian regulators require from foreign issueres?An update on legal issues and developments in the mining industry, PDAC and Natural Resource and Energy Law (O, March 10, 15p. ppt slidesCanada, OntarioLegal - overview
DS1996-0918
1996
McCombe, D.A.McCombe, D.A.Technical report writing and common terminology #1Prospectors and Developers Association of Canada (PDAC) Short Course for Developing Country, pp. 21-92GlobalMining reports, Short course notes
DS1860-0418
1883
Mccombie, T.M.Mccombie, T.M.Ten Pounds and Ten Days by One Who Has Suffered ItUnknown., 56P.Africa, South AfricaLegal
DS1986-0505
1986
McConchie, D.M.Lucas, H., Muggeride, M.T., McConchie, D.M.The nature of iron in kimberlitic ilmenites and chromitesProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 60-62GlobalMineral chemistry
DS1986-0545
1986
McConchie, D.M.McConchie, D.M., Smith, C.B.Iron oxides in pisolite like clasts in Ellendale lamproite intrusionsProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 190-192AustraliaLamproite
DS1989-0900
1989
McConchie, D.M.Lucas, H., Muggeridge, M.T., McConchie, D.M.Iron in kimberlitic ilmenites and chromian spinels: a survey of analyticaltechniquesGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 311-320GlobalGeochemistry, Ilmenites
DS1989-0974
1989
McConchie, D.M.McConchie, D.M., Smith, C.B.Iron-oxides as paleotemperature indicators in Ellendale lamproiteintrusionsGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 520-527AustraliaDeposit - Ellendale, Paleotemperature
DS200612-1362
2006
McConnellStachel, T., Paulen, R., Prior, G., Micea, C., Cubbing, M., McConnell, GlennDiamond exploration in western sedimentary basin ( glacial processes, till sampling, geophysics)Calgary Mining Forum, April 28 Short Course # 3, NOTICE only meg.calgary.ab.caCanada, AlbertaExploration - program
DS1986-0291
1986
McConnell, D.A.Gilbert, M.C., McConnell, D.A.The southern margin of North American craton: problems and constraints on possible modelsGeological Society of America (GSA) Abstract Volume, Vol. 18, No. 6, p. 613. (abstract.)MidcontinentBlank
DS1990-1002
1990
McConnell, D.A.McConnell, D.A.Crustal shortening of the Wichita Uplift: Implications for the southern midcontinent -Texas craton transectGeological Society of America (GSA) Abstracts with programs, South-Central, Vol. 22, No. 1, p. 27GlobalMidcontinent, Tectonics
DS1990-1003
1990
McConnell, D.A.McConnell, D.A., Gilbert, M.C.Cambrian extensional tectonics and magmatism within the Southern Oklohomaaulocogen.Tectonophysics, Vol. 174, pp. 147-57.GlobalMidcontinent Rifting, Tectonics
DS1990-1004
1990
McConnell, D.A.McConnell, D.A., Goydas, M.J., Smith, G.N., Chitwood, J.P.Morphology of the frontal fault zone, southwest Oklahoma: implications for deformation and deposition in the Wichita uplift and Anadarko basinGeology, Vol. 18, No. 7, July pp. 634-637GlobalTectonics
DS1994-0441
1994
McConnell, D.A.Dominic, J.B., McConnell, D.A.The influence of structural lithic units in fault related folds, SeminoeMountains, WyomingJournal of Structural Geology, Vol. 16, No. 6, pp. 769-780WyomingStructure, Seminoe area
DS1996-0919
1996
McConnell, J.McConnell, J., Ryan, B.The search for kimberlite and lamproite intrusions in northeasternLabrador: results of a surficial sediment.Newfoundland Department of Mines, Report, No. 96-1, pp. 193-206.LabradorGeochemistry -till, bedrock orientiation study, Kimberlite, lamproite
DS2001-0752
2001
McConnell, J.McConnell, J.Snap Lake projectProspectors and Developers Association of Canada (PDAC) 2001, 1p. abstractNorthwest TerritoriesDiamond - exploration brief overview
DS2001-1170
2001
McConnell, J.Turner, R., McConnell, J.The Snap Lake diamond deposit, Northwest TerritoriesProspectors and Developers Association of Canada (PDAC) 2001, 1p. abstractNorthwest TerritoriesNews item, De Beers
DS200512-0703
2005
McConnell, J.McConnell, J.Canada's next diamond mine: the De Beers Snap Lake diamond project.British Columbia & Yukon Mineral Exploration Roundup, Jan.24-27th., p. 85-86.Canada, Northwest TerritoriesNews item - brief overview, De Beers
DS1985-0429
1985
Mcconnell, J.W.Mcconnell, J.W., Batterson, M.J.The Strange Lake Zr-y-rare Earth Elements (ree)-nb-be Deposit: an Exploration Geochemical Profile.11th. International Geochem. Symposium Held Toronto, April 28-may, ABSTRACT VOLUME, P. 70. (abstract.).Canada, LabradorAlkaline Rocks
DS1950-0492
1959
Mcconnell, R.B.Mcconnell, R.B.Notes on the Geology and Geomorphology of the Bechuana land Protectorate.Asoc. De Serv. Geol. Afr. Xx Sess. Cong. Geol. International Cuida, PP. 175-186.BotswanaGeology, Geomorphology
DS1960-0072
1960
Mcconnell, R.B.Mcconnell, R.B., Dixon, C.G.A Geological Map of British GuianaInternational Geol. Cong., 21st. sess. pat 9, pp. 39-46.GlobalMap - Description
DS1960-1165
1969
Mcconnell, R.B.Mcconnell, R.B.Fundamental Fault Zones in the Guiana and West African Shields in Relation to Presumed Axes of Atlantic Spreading.Geological Society of America (GSA) Bulletin., Vol. 80, PP. 1775-1782.South America, Guiana, West AfricaGeotectonics
DS1987-0451
1987
McConnville, P.McConnville, P., Reynolds, J.H.Cosmogenic Helium in Sierra Leone diamonds?Eos, Vol. 68, No. 44, November 3, p. 1514. abstract onlySierra LeoneNoble gases, Geochemistry
DS1989-0975
1989
McConville, P.McConville, P., Reynolds, J.H.Cosmogenic helium and volatile rich fluid in Sierra Leone alluvialdiamondsGeochimica et Cosmochimica Acta, Vol. 53, No. 9, September pp. 2365-2375Sierra LeoneGeochemistry, helium
DS1989-0976
1989
McConville, P.McConville, P., Reynolds, J.H.Cosmogenic helium and volatile rich mantle fluid in Sierra Leone diamonds #1Meteoritics, Vol. 24, No. 4, December, pp. 301-302Sierra LeoneGeochemistry, Isotope -helium
DS1989-0977
1989
McConville, P.McConville, P., Reynolds, J.H.Cosmogenic helium and volatile rich mantle fluid in Sierra Leone diamonds #252nd Annual Meeting Of The Meteoritical Society, Lpi Contribution, Vol. 712, p. 154. AbstractSierra LeoneGeochemistry, Isotope -helium
DS1991-1098
1991
McConville, P.McConville, P., Reynolds, J.H., Epstein, S., Roedder, E.Implanted 3He, 4He and Xe in further studies of diamonds from westernAustraliaGeochimica et Cosmochimica Acta, Vol. 55, pp. 1977-1989AustraliaLamproites, Argyle, Ellendale, noble gases, geochronology
DS201709-1949
2017
McCook, A.Abritis, A., McCook, A.Cash bonuses for peer reviewed papers go global. Overview citing Chin a excessive payments.Retraction Watch, Aug. 10, 3p.Global, Chinaresearch papers

Abstract: China is well known for the generous bonuses it pays scientists who land a peer-reviewed publication in a prestigious research journal. But scientists in many countries are reaping similar bounties. After spotting a discussion on a scholarship listserv about the topic, we dug further to find official documents on such payments from institutions named in the thread. Searching the internet using key terms such as “publishing cash incentives” and “schemes cash publishing” widened our net. We relied mostly on online documents in English, so we surely missed some policies. The numbers in the graphic below represent the maximum amounts we uncovered at a particular institution in a specific country. Even under those constraints, we documented publishing incentives from all corners of the globe, including at a number of U.S. institutions. Awards are primarily cash; some are as small as the $10 that Oakwood University in Huntsville, Alabama, bestows on authors when their papers are cited in the literature. Some institutions designate payments for faculty members, whereas others reward student authors.
DS1950-0287
1956
Mccord, R.G.Mccord, R.G.Fifty Years of Dreaming and Digging in North America's Only diamond Mine.Arkansaw DEMOCRAT SUNDAY MAGAZINE (LITTLE ROCK), AUGUST 5TH. P. 1; P. 7; P. 9.United States, Gulf Coast, Arkansas, PennsylvaniaMining, Sampling, Diamond, Production, History
DS201212-0322
2012
McCormack, R.J.Hunt, S.A., Davies, D.R., Walker, A.M., McCormack, R.J., Wills, A.S., Dobson, D.P., Li, Li.On the increase in thermal diffusivity caused by the perovskite to post-perovskite phase transition and its implications for mantle dynamics.Earth and Planetary Science Letters, Vol. 319-320, pp. 96-103.MantleGeodynamics
DS1975-1138
1979
Mccormick, G.Mccormick, G., Heathcote, R.Mineralogy of the Morrilton Alvikite Dike, Conway County, ArkansasGeological Society of America (GSA), Vol. 11, P. 163. (abstract.).United States, Gulf Coast, Arkansas, Conway CountyBlank
DS1986-0546
1986
McCormick, G.R.McCormick, G.R.Ferromagnesian mineral chemistry of Arkansaw carbonatite intrusionsGeological Association of Canada (GAC) Annual Meeting, Vol. 11, p. 100. (abstract.)Midcontinent, Arkansas, Gulf CoastPotash Sulphur Springs, Morrilton
DS1987-0452
1987
McCormick, G.R.McCormick, G.R., Heathcote, R.C.Mineral chemistry and petrogenesis of carbonatite intrusions, Perry and Conway Counties, ArkansawAmerican Mineralogist, Vol. 72, No. 1-2, Jan-Feb. pp. 59-66ArkansasUSA, Carbonatite
DS1989-0610
1989
McCormick, G.R.Heathcote, R.C., McCormick, G.R.Major-cation substitution in phlogopite and evolution of carbonatite In the Potash Sulfur Springs complex, Garland County, ArkansawAmerican Mineralogist, Vol. 74, No. 1-2, January-February pp. 132-140ArkansasAnalyses: Clinopyroxenes, phlogopite
DS1991-0005
1991
McCormick, G.R.Ahmed, Z., McCormick, G.R.A newly discovered kimberlitic rock from PakistanMineralogical Magazine, Vol. 54, December pp. 537-546PakistanKimberlite, Mineral chemistry
DS1994-1141
1994
McCormick, G.R.McCormick, G.R., Le Bas, M.J.Biotite-phlogopite crystallization in carbonatite magmasGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p. PosterGlobalCarbonatite, Mineralogy
DS1996-0920
1996
McCormick, G.R.McCormick, G.R., Le Bas, M.J.Phlogopite crystallization in carbonatitic magmas from UgandaCanadian Mineralogist, Vol. 34, pt. 2, April pp. 469-478.UgandaCarbonatite, Mineralogy, petrology
DS1984-0502
1984
Mccormick, T.C.Mccormick, T.C.Crystal Chemistry and Breakdown Reactions of Aluminous Mantle Derived omphacites.Ph.d. Thesis, Arizona State University, 136P.South AfricaMineralogy, Inclusions, Roberts Victor, Bellsbank, Rietfontein
DS1984-0683
1984
Mccormick, T.C.Smyth, J.R., Mccormick, T.C., Caporuscio, F.A.Petrology of a Suite of Eclogitic Inclusions from the Bobbejaan Kimberlite 1. Two Unusual Corundum Bearing Kyanite Eclogites.Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 109-119.South AfricaMicroprobe Analyses, Bellsbank, Petrography, Mineral, Bulk Chemi
DS1986-0547
1986
McCormick, T.C.McCormick, T.C.Crystal chemical aspects of nonstoichiometric pyroxenesAmerican Mineralogist, Vol. 71, pp. 1434-1440GlobalGenesis
DS1987-0453
1987
McCormick, T.C.McCormick, T.C., Hazen, R.M., Angel, R.J.Effect of vacancies on compressibilities of mantle ophacitesGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p.765. abstracSouth AfricaKimberlite
DS1987-0654
1987
McCormick, T.C.Scambos, T.A., Smyth, J.R., McCormick, T.C.Crystal structure refinement of high sanidine from the upper mantleAmerican Mineralogist, Vol. 72, pp. 973-978South AfricaRoberts Victor, Analyses
DS1989-0978
1989
McCormick, T.C.McCormick, T.C.Banded eclogite xenoliths: some constraints on chemical equilibration and metasomatism in the mantleEos, Vol. 70, No. 43, October 24, p. 1411. AbstractSouth AfricaRoberts Victor, Eclogites
DS1989-0979
1989
McCormick, T.C.McCormick, T.C., Hazen, R.M., Angel, R.Compressability of omphacite to 60 KBAR: role of vacanciesAmerican Mineralogist, Vol. 74, No. 11-12, pp. 1287-1292South AfricaCrystallography, Eclogites
DS1989-1414
1989
McCormick, T.C.Smyth, J.R., Caporusco, F.A., McCormick, T.C.Mantle eclogites- evidence of igneous fractionation in the mantleEarth and Planetary Science Letters, Vol. 93, No. 1, May pp. 123-132GlobalMantle, Eclogite
DS1989-1415
1989
McCormick, T.C.Smyth, J.R., Caporusco, F.A., McCormick, T.C.Mantle ecologites- evidence of igneous fractionation in the mantleEarth and Planetary Science Letters, Vol. 93, No. 1, May pp. 133-141GlobalMantle, Eclogite
DS1990-1005
1990
McCormick, T.C.McCormick, T.C., Smyth, J.R.Petrology of secondary phases in mantle eclogiteEos, Vol. 71, No. 17, April 24, p. 524 Poster Abstract onlySouth AfricaBellsbank, Roberts Victor, Eclogites
DS1991-1099
1991
McCormick, T.C.McCormick, T.C., Smyth, J.R., Caporuscio, F.A.Secondary phases in mantle eclogitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 267-269South AfricaBellsbank Roberts Victor, Geochemistry, major element, mineralogy, texture
DS1991-1620
1991
McCormick, T.C.Smythe, J.R., McCormick, T.C., Caporuscio, F.A.Pyroxene crystal chemistry and the evolution of eclogites in the mantleProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 385-387South AfricaCoesite, grospydite, Mineral chemistry
DS1994-1142
1994
McCormick, T.C.McCormick, T.C., Smyth, J.R., Caporuscio, F.A.Chemical systematics of secondary phases in mantle eclogitesProceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 405-423.MantleEclogites
DS1995-1506
1995
McCorquodalePokhilenko, N.P., McDonald, J.A., Melnyk, W., McCorquodaleIndicator minerals of CL 25 kimberlite pipe, Slave Craton, northwest TerritoriesProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 444-445.Northwest TerritoriesGeochemistry -indicator minerals, Deposit -CL-25 pipe
DS1997-0917
1997
McCorquodalePokhilenko, N.P., McDonald, J., Melnik, U., McCorquodaleIndicator minerals of CL-25 kimberlite pipe Slave Craton, NorthwestTerritories, Canada.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 550-558.Northwest TerritoriesGeochemistry, Deposit - CL-25
DS2001-0568
2001
McCourtKampunzu, A.B., Atekwana, McCourt, Tombale, RanganaiInteraction between Kaapvaal and Zimbabwe Cratons during the Neoarchean and implications for transition..Slave-Kaapvaal Workshop, Sept. Ottawa, 3p. abstractSouth Africa, ZimbabweArchean and post Archean plate tectonic styles, Limpopo Shashe belt
DS201604-0636
2016
McCourt, M.W.Thomas, R.J, Spencer, C., Bushi, A.M., Baglow, N., Gerrit de Kock, B., Hortswood, M.S.A., Hollick, L., Jacobs, J., Kajara, S., Kaminhanda, G., Key, R.M., Magana, Z., McCourt, M.W., Momburi, P., Moses, F., Mruma, A., Myamilwa, Y., Roberts, N.M.W., HamisiGeochronology of the centra Tanzania craton and its southern and eastern orogenic margins.Precambrian Research, in press available 57p.Africa, TanzaniaGeochronology

Abstract: Geological mapping and zircon U-Pb/Hf isotope data from 35 samples from the central Tanzania Craton and surrounding orogenic belts to the south and east allow a revised model of Precambrian crustal evolution of this part of East Africa. The geochronology of two studied segments of the craton shows them to be essentially the same, suggesting that they form a contiguous crustal section dominated by granitoid plutons. The oldest orthogneisses are dated at ca. 2820 Ma (Dodoma Suite) and the youngest alkaline syenite plutons at ca. 2610 Ma (Singida Suite). Plutonism was interrupted by a period of deposition of volcano-sedimentary rocks metamorphosed to greenschist facies, directly dated by a pyroclastic metavolcanic rock which gave an age of ca. 2725 Ma. This is supported by detrital zircons from psammitic metasedimentary rocks, which indicate a maximum depositional age of ca. 2740 Ma, with additional detrital sources 2820 and 2940 Ma. Thus, 200 Ma of episodic magmatism in this part of the Tanzania Craton was punctuated by a period of uplift, exhumation, erosion and clastic sedimentation/volcanism, followed by burial and renewed granitic to syenitic magmatism. In eastern Tanzania (Handeni block), in the heart of the East African Orogen, all the dated orthogneisses and charnockites (apart from those of the overthrust Neoproterozoic granulite nappes), have Neoarchaean protolith ages within a narrow range between 2710 and 2630 Ma, identical to (but more restricted than) the ages of the Singida Suite. They show evidence of Ediacaran "Pan-African" isotopic disturbance, but this is poorly defined. In contrast, granulite samples from the Wami Complex nappe were dated at ca. 605 and ca. 675 Ma, coeval with previous dates of the "Eastern Granulites" of eastern Tanzania and granulite nappes of adjacent NE Mozambique. To the south of the Tanzania Craton, samples of orthogneiss from the northern part of the Lupa area were dated at ca. 2730 Ma and clearly belong to the Tanzania Craton. However, granitoid samples from the southern part of the Lupa "block" have Palaeoproterozoic (Ubendian) intrusive ages of ca. 1920 Ma. Outcrops further south, at the northern tip of Lake Malawi, mark the SE continuation of the Ubendian belt, albeit with slightly younger ages of igneous rocks (ca. 1870-1900 Ma) which provide a link with the Ponte Messuli Complex, along strike to the SE in northern Mozambique. In SW Tanzania, rocks from the Mgazini area gave Ubendian protolith ages of ca. 1980-1800 Ma, but these rocks underwent Late Mesoproterozoic high-grade metamorphism between 1015 and 1040 Ma. One granitoid gave a crystallisation age of ca. 1080 Ma correlating with known Mesoproterozoic crust to the east in SE Tanzania and NE Mozambique. However, while the crust in the Mgazini area was clearly one of original Ubendian age, reworked and intruded by granitoids at ca. 1 Ga, the crust of SE Tanzania is a mixed Mesoproterozoic terrane and a continuation from NE Mozambique. Hence the Mgazini area lies at the edge of the Ubendian belt which was re-worked during the Mesoproterozoic orogen (South Irumide belt), providing a further constraint on the distribution of ca. 1 Ga crust in SE Africa. Hf data from near-concordant analyses of detrital zircons from a sample from the Tanzania Craton lie along a Pb-loss trajectory (Lu/Hf = 0), extending back to ?3.9 Ga. This probably represents the initial depleted mantle extraction event of the cratonic core. Furthermore, the Hf data from all igneous samples, regardless of age, from the entire study area (including the Neoproterozoic granulite nappes) show a shallow evolution trend (Lu/Hf = 0.028) extending back to the same mantle extraction age. This implies the entire Tanzanian crust sampled in this study represents over 3.5 billion years of crustal reworking from a single crustal reservoir and that the innermost core of the Tanzanian Craton that was subsequently reworked was composed of a very depleted, mafic source with a very high Lu/Hf ratio. Our study helps to define the architecture of the Tanzanian Craton and its evolution from a single age-source in the early Eoarchaean.
DS1987-0454
1987
McCourt, S.McCourt, S., Vearncombe, J.R.Shear zones bounding the central zone of the Limpopo mobile belt, SouthernAfricaJournal of Structural Geology, Vol.9, No.2, pp. 127-137South AfricaStructure, Shear
DS1993-1590
1993
McCourt, S.Thomas, R.J., Von Veh, M.W., McCourt, S.The tectonic evolution of southern Africa: an overviewJournal of African Earth Sciences, Vol. 16, No. 1/2, January-February pp. 5-24South AfricaTectonics, Review
DS1993-1591
1993
McCourt, S.Thomas, R.J., Von Veii, M.W., McCourt, S.The tectonic evolution of southern Africa: an overviewJournal of African Earth Sciences, Vol. 16, No. 1/2, January/February pp. 5-24.South AfricaTectonics, Review
DS1995-1206
1995
McCourt, S.McCourt, S.The crustal architecture of the Kaapvaal crustal block South Africa, between 3.5 and 2.0 Ga: a synopsisMineralium Deposita, Vol. 30, No. 2, pp. 89-97South AfricaTectonics, structure, Kaapvaal craton, geochronology
DS1995-1285
1995
McCourt, S.Mogk, D.W., McCourt, S.Archean high grade gneiss belts Central Zone Limpopo Belt and northern Wyoming Province -chips off same block?Centennial Geocongress (1995) Extended abstracts, Vol. 1, p. 193-196. abstractSouth Africa, Wyoming, United StatesTectonics
DS1995-1971
1995
McCourt, S.Van Reenen, D.D., McCourt, S., Smit, C.A.Are the Southern and Northern marginal zones of Limpopo belt related to a single continental collisional event. #1South African Journal of Geology, Vol. 98, No. 4, pp. 498-504.South Africa, ZimbabweLimpopo Belt, Kaapvaal craton, Zimbabwe craton
DS1996-1464
1996
McCourt, S.Van Reenen, D.D., McCourt, S., Smit, C.A.Are the southern and northern marginal zones of Limpopo Belt related to a single continental collisional event #2South Africa Journal of Geology, Vol. 95, No. 4, pp. 498-504South AfricaTectonics, Craton, Limpopo Belt
DS1998-0975
1998
McCourt, S.McCourt, S., Armstrong, R.A.Shrimp uranium-lead (U-Pb) zircon geochronology of granites from the Central Zone, LimpopoBelt: implications age Orogeny.South African Journal of Geology, Vol. 101, No. 4, Dec. 1, pp. 329-South AfricaGeochronology, Limpopo Orogeny - not specific to diamonds
DS2001-0753
2001
McCourt, S.McCourt, S., Armstrong, R.The architecture and evolution of the northern Kaapvaal Limpopo Terrane, South Africa.Slave-Kaapvaal Workshop, Sept. Ottawa, 5p. abstractSouth AfricaTectonics, Limpopo Belt
DS2002-0785
2002
McCourt, S.Johnson, S.T., McCourt, S., Bisnath, A., Mitchell, A.A.The Tugela Terrane Natal belt: Kibaran magmatism and tectonism along the southeast margin of the Kaapvaal Craton.Geological Society of South Africa, Vol. 105, No. 1, pp. 1-14.South AfricaCraton - tectonics
DS201312-0593
2013
McCourt, S.McCourt, S., Armstrong, R.A., Jelsma, H., Mapeo, R.B.M.New U-Pb SHRIMP ages from the Lubango region, sw Angola: insights into the Paleoproterozoic evolution of the Angolan shield, southern Congo craton, Africa.Journal of the Geological Society, Vol. 170, pp. 353-363.Africa, AngolaGeochronology
DS1900-0783
1909
Mccourt, W.E.Mccourt, W.E.Diamond in Arkansaw. #1Science., Vol. 30, JULY 30TH. P. 127. ALSO: ST. LOUIS Academy of Science TRANSUnited States, Gulf Coast, Arkansas, PennsylvaniaDiamond Occurrence
DS2002-0659
2002
McCoy, D.T.Hart, C.J.R., McCoy, D.T., Goldfarb, Smith, RobertsGeology, exploration and discovery in the Tintin a gold province Alaska and YukonSociety of Economic Geologists Special Publication, No.9,pp.241-74.Yukon, AlaskaGold, Deposit - Tintina area
DS201012-0480
2010
McCoy, T.J.McCoy, T.J.Mineralogical evolution of meteorites.Elements, Vol. 6, pp. 19-23.MantleMeteorite
DS201707-1328
2017
McCoy-West, A.J.Giuliani, A.M., Tappe, S., Rooney, T.O., McCoy-West, A.J., Yaxley, G.M., Mezger, K.Editorial: the role of intraplate magmas and their inclusions in Earth's mantle evolution.Chemical Geology, Vol. 455, pp. 1-5.Mantlemagmatism

Abstract: Carbon isotope compositions and the distribution of nitrogen and hydrogen in diamonds from 18 eclogites from Nurbinskaya kimberlites were studied in situ in polished plates. Cathodoluminescence images show that most of the diamonds have complex growth structures with distinctive cores, intermediate and rim zones. In some diamonds the cores display dissolution features, and intermediate growth zones are separated from the cores by narrow rounded oscillatory zones. At least three crystals show interrupted multistage diamond growth; variations in ? ¹³C of 2–3‰ occur across the contacts between distinct zones. Generally, ?¹³C within the diamond cores varies only by 1–2‰, in rare cases up to 3.3‰. ?¹³C values are usually lower in the intermediate zones and drop further towards the rims by up to 3‰. High-resolution SIMS profiles show that variations in ?¹³C across the diamond growth zones are sharp with no evidence of diffusive relaxation.
DS201809-2070
2018
McCoy-West, A.J.McCoy-West, A.J., Fitton, J.G., Pons, M-L., Inglis, E.C., Williams, H.M.The Fe and Zn isotope composition of deep mantle source regions: insight from Baffin Island picrites.Geochimica et Cosmochimica Acta, Vol. 238, pp. 542-562.Canada, Nunavut, Baffin Islandpicrites

Abstract: Young (61?Ma) unaltered picrites from Baffin Island, northeast Canada, possess some of the highest 3He/4He (up to 50?Ra) seen on Earth, and provide a unique opportunity to study primordial mantle that has escaped subsequent chemical modification. These high-degree partial melts also record anomalously high 182W/184W ratios, but their Sr-Nd-Hf-Pb isotopic compositions (including 142Nd) are indistinguishable from those of North Atlantic mid-ocean ridge basalts. New high precision Fe and Zn stable isotope analyses of Baffin Island picrites show limited variability with ?56Fe ranging from ?0.03‰ to 0.13‰ and ?66Zn varying from 0.18‰ to 0.28‰. However, a clear inflection is seen in both sets of isotope data around the composition of the parental melt (MgO?=?21?wt%; ?56Fe?=?0.08?±?0.04‰; and ?66Zn?=?0.24?±?0.03‰), with two diverging trends interpreted to reflect the crystallisation of olivine and spinel in low-MgO samples and the accumulation of olivine at higher MgO. Olivine mineral separates are significantly isotopically lighter than their corresponding whole rocks (?56Fe????0.62‰ and ?66Zn????0.22‰), with analyses of individual olivine phenocrysts having extremely variable Fe isotope compositions (?56Fe?=??0.01‰ to ?0.80‰). By carrying out modelling in three-isotope space, we show that the very negative Fe isotope compositions of olivine phenocryst are the result of kinetic isotope fractionation from disequilibrium diffusional processes. An excellent correlation is observed between ?56Fe and ?66Zn, demonstrating that Zn isotopes are fractionated by the same processes as Fe in simple systems dominated by magmatic olivine. The incompatible behaviour of Cu during magmatic evolution is consistent with the sulfide-undersaturated nature of these melts. Consequently Zn behaves as a purely lithophile element, and estimates of the bulk Earth Zn isotope composition based on Baffin Island should therefore be robust. The ancient undegassed lower mantle sampled at Baffin Island possesses a ?56Fe value that is within error of previous estimates of bulk mantle ?56Fe, however, our estimate of the Baffin mantle ?66Zn (0.20?±?0.03‰) is significantly lower than some previous estimates. Comparison of our new data with those for Archean and Proterozoic komatiites is consistent with the Fe and Zn isotope composition of the mantle remaining constant from at least 3?Ga to the present day. By focusing on large-degree partial melts (e.g. komatiites and picrites) we are potenitally biasing our record to samples that will inevitably have interacted with, entrained and melted the ambient shallow mantle during ascent. For a major element such as Fe, that will continuosly participate in melting as it rises through the mantle, the final isotopic compositon of the magama will be a weighted average of the complete melting column. Thus it is unsuprising that minimal Fe isotope variations are seen between localities. In contrast, the unique geochemical signatures (e.g. He and W) displayed by the Baffin Island picrites are inferred to solely originate from the lowermost mantle and will be continuously diluted upon magma ascent.
DS201912-2805
2019
McCoy-West, A.J.McCoy-West, A.J., Chowdhury, P., Burton, K.W., Sossi, P., Nowell, G,M., Fitton, J.G., Kerr, A.C., Cawood, P.A., Williams, H.M.Extensive crustal extraction in Earth's early history inferred from molybdenum isotopes.Nature Geoscience, Vol. 12, pp. 946-951.Mantlepicrites

Abstract: Estimates of the volume of the earliest crust based on zircon ages and radiogenic isotopes remain equivocal. Stable isotope systems, such as molybdenum, have the potential to provide further constraints but remain underused due to the lack of complementarity between mantle and crustal reservoirs. Here we present molybdenum isotope data for Archaean komatiites and Phanerozoic komatiites and picrites and demonstrate that their mantle sources all possess subchondritic signatures complementary to the superchondritic continental crust. These results confirm that the present-day degree of mantle depletion was achieved by 3.5 billion years ago and that Earth has been in a steady state with respect to molybdenum recycling. Mass balance modelling shows that this early mantle depletion requires the extraction of a far greater volume of mafic-dominated protocrust than previously thought, more than twice the volume of the continental crust today, implying rapid crustal growth and destruction in the first billion years of Earth’s history.
DS1996-0921
1996
McCracken, A.D.McCracken, A.D., Armstrong, D.K., McGregor, D.C.Fossils as indicators of thermal alteration associated with kimberlitesGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 143-145.Quebec, OntarioPaleontology, Thermal histories
DS2000-0644
2000
McCracken, A.D.McCracken, A.D., Armstrong, D.K., Bolton, T.E.Conodonts and corals in kimberlite xenoliths confirm a Devonian seaway in central Ontario and Quebec.Canadian Journal of Earth Sciences, Vol. 37, No.12, Dec. pp. 1651-63.Ontario, QuebecXenoliths, paleontology, Kirkland Lake area, Lake Timiskaming
DS1993-0993
1993
McCracken, M.McCracken, M., Major, T.Diamond mining by Poseidon Bow River Diamond Mine Limited, Bow River WAAustralia Min. Met. Mawby Memorial Volume, Mon. 19, pp. 1449-1452.AustraliaMining, Deposit -Bow River
DS1920-0435
1929
Mccrae, J.Crocker, H.J., Mccrae, J.South Africa and Science, a HandbookJohannesburg: Hortors Ltd., 313P.South AfricaHistory, Kimberley
DS2000-0645
2000
McCraken, A.D.McCraken, A.D., Bolton, T.E.Geology and paleontology of the southeast Arctic Platform and southern Baffin Island, Nunavut.Geological Survey of Canada (GSC) Bulletin., No. 557, 248p.Northwest Territories, Nunavut, Baffin IslandArctic Platform
DS1989-0980
1989
McCrank, G.F.D.McCrank, G.F.D., Kamineni, D.C., Ejeckam, R.B., Sikorsky, R.Geology of the East Bulletin Lake gabbro- anorthosite pluton, Algoma OntarioCanadian Journal of Earth Sciences, Vol. 26, No. 2, February pp. 357-375OntarioAnorthosite
DS1975-1139
1979
Mccrann, T.Mccrann, T.Diamond Prospect Sparkles AgainThe Age (melbourne), Dec. 12TH.Australia, Western AustraliaArgyle, Ord River, Northern Territory
DS1975-1140
1979
Mccrann, T.Mccrann, T.Foreign Equity Remains a Problem for AshtonThe Age (melbourne), Dec. 20TH.Australia, Western AustraliaArgyle, Shares
DS1975-1141
1979
Mccrann, T.Mccrann, T.Gems Spark Dilemma on CartelThe Age (melbourne), Dec.Australia, Western AustraliaArgyle, Shares, Markets, Cso
DS1975-1142
1979
Mccrann, T.Mccrann, T.Conzinc in New Diamond StrikeThe Age (melbourne), OCTOBER 22ND.Australia, Western AustraliaCra, Lake Argyle, Sampling
DS1975-1143
1979
Mccrann, T.Mccrann, T.Diamonds Are Sometimes EmbarrassingThe Age (melbourne), APRIL, 6TH.Australia, Western AustraliaLake Argyle, Uranerz, Markets
DS1980-0228
1980
Mccrann, T.Mccrann, T.Glitter Grows.... Ashton Diamond Discovery- How Much?The Age (melbourne), JANUARY 10TH, P. 13.Australia, Western AustraliaSampling, Market, Investment, Prices, Shares, Argyle
DS1981-0293
1981
Mccrann, T.Mccrann, T.Cso Can Add Sparkle to Argyle's Dull FacetsThe Age (melbourne), SEPT. 4TH. P. 17, P. 19.Australia, Western AustraliaArgyle, Cso, Markets
DS1981-0294
1981
Mccrann, T.Mccrann, T.Too Many Facets to the Argyle ReportsThe Age (melbourne), JULY, 11TH. P. 33.Australia, Western AustraliaCra, Ashton, Dispute, Sampling
DS1981-0295
1981
Mccrann, T.Mccrann, T.Exchange Must Get Answers from EndeavourThe Age (melbourne), JULY 8TH.Australia, Western AustraliaMarkets, Investment, Shares, Endeavour Resources
DS1996-0922
1996
McCreary, J.H.McCreary, J.H.ISO 14000: a framework for co-ordinating existing environmental managementresponsibilitiesThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 89, No. 999, April pp. 65-70CanadaMining, Environment
DS201312-0594
2013
McCreary, T.McCreary, T.Mining aboriginal success: the politics of difference in continuing education for industry needs.The Canadian Geographer, Vol. 57, 3, pp. 280-288.CanadaCSR
DS1992-0813
1992
McCreath, D.R.Kaiser, P.K., McCreath, D.R.Rock support in mining and underground constructionA.a. Balkema, 706p. $ 175.00GlobalBook -ad, Mining -rock support
DS201012-0481
2010
McCreath, J.A.McCreath, J.A., Finch, A.A., Donaldson, C.H., Armour-Brown, A.The petrology and petrogenesis of one of the world's biggest Ta deposits - the Motzfeldt Centre, South Greenland.International Workshop Geology of Rare Metals, held Nov9-10, Victoria BC, Open file 2010-10, extended abstract pp.43.Europe, GreenlandAlkalic
DS1995-2091
1995
McCuaig, T.C.Xie, Q., McCuaig, T.C., Kerrich, R.Secular trends in the melting depths of mantle plumes: evidence systematics of Archean high magnesium lavasChemical Geology, Vol. 126, No. 1, Nov. 20, pp. 29-42MantleBasalts, Geochemistry
DS201112-0333
2010
McCuaig, T.C.Ford, A., McCuaig, T.C.The effect of map scale on geological complexity for computer-aided exploration targeting.Ore Geology Reviews, Vol. 38, pp. 156-167.TechnologyMethodology - computing
DS201112-0659
2010
McCuaig, T.C.McCuaig, T.C., Bereford, S., Hronsky, J.Translating the mineral systems approach into an effective exploration targeting system.Ore Geology Reviews, Vol. 38, pp. 128-38.TechnologyMethodology - targets not specific to diamonds
DS201412-0579
2014
McCubbin, F.M.Mikhail, S., Howell, D., McCubbin, F.M.Evidence for multiple diamondite-forming events in the mantle.American Mineralogist, Vol. 99, pp. 1537-1543.MantleDiamondite
DS201909-2062
2019
McCubbin, F.M.Mikhail, S., McCubbin, F.M., Jenner, F.E., Shirey, S.B., Rumble, D., Bowden, R.Diamonites: evidence for a distinct tectono-thermal diamond - forming event beneath the Kaapvaal craton.Contributions to Mineralogy and Petrology, in press available, 15p. PdfAfrica, South Africadiamondite
DS201801-0037
2018
McCubbing, M.McCubbing, M.Using diamond characterization to refine micro and macro processing and recovery.Vancouver Kimberlite Cluster , 1p. AbstractTechnologydiamond recovery
DS201902-0298
2019
McCubbing, M.McCubbing, M.Using diamond characterization to refine micro and macro diamond processing and recovery.Vancouver Kimberlite , Jan. 31, 1p. AbstractGlobalmicrodiamonds

Abstract: Bulk samples for both micro and macro diamond recovery are very costly, and typically only a small amount of quantitative data is collected, this is particularly the case for micro diamonds. Standard practise is to only provide information on the number of diamonds, their sizes, and weight. However, a large amount of quantitative data can be collected for both micro and macro diamonds to understand their unique characteristics. This data can be used to enhance diamond recovery through optimization of standard processes or introduction of appropriate processing equipment. The more information that can be collected in the prefeasibility stage, the more streamlined the diamond recovery circuit can be made, and the less diamond loss will occur. This presentation will provide an overview of standard recovery methods for micro and macro diamonds as well as other test work that can be applied to the parcels. The resulting data can provide information on the unique properties for that parcel in order to customize process flows and optimize recovery. Caustic fusion is a widely accepted method for micro diamond recovery. Thanks to its high liberation efficiency by dissolution, caustic fusion can also be an effective tool for auditing process streams. Any additional diamonds recovered through these audits can be studied to determine if crusher gap or pressure settings are appropriate for optimal liberation or if there are any other properties the diamonds may have that inhibits proper recovery, such as unique fluorescence characteristics, abundant inclusions, coats, etc. Dense media separation (DMS) is currently the most common method of concentration for the recovery of macro diamonds. Process flows can be modified in attempts to optimize plant performance but there can often be sacrifices. Diamond breakage can be assessed to give insight on the type of damage occurring and if the source is mechanical or related to the properties of the diamonds themselves. By considering the diamond breakage, updated size frequency distribution plots can be made, and predictions on the largest diamond expected for the kimberlite tonnage can be made. This information can also be used when determining parameters such as crusher gap settings. In addition, densiometric analyses can provide a useful profile of the predominant mineral background in the DMS process material to determine the appropriate cut point. Once diamonds are recovered, the resulting parcels can have a story to tell in addition to the diamond value. Magnetic susceptibility investigations can provide information on included diamonds and how magnetics could be incorporated into a flow sheet for pre-recovery concentration. Diamond Typing based on their nitrogen content and aggregation states can identify populations of stones that could make recovery less effective. Type II diamonds are commonly known for being large and high value, however, they also exhibit low to no luminescence under conventional x-ray recovery equipment. Luminescence profiles can be measured and provide feedback on the appropriate x-ray thresholds for the recovery equipment. Being able to predict the characteristics of the diamond populations which will be mined can provide information to design a primary ore recovery circuit to recover these stones. There is a wide array of process equipment available for diamond recovery, some very old, and some very new, however there are ways to provide data on what combination will work best.
DS2001-1304
2001
McCullochZhang, M., Stephenson, P.J., O'Reilly, S.Y., McCullochPetrogenesis and geodynamic implications of Late Cenozoic basalts in northQueensland.. trace elements..Journal of Petrology, Vol. 42, No. 4, Apr. pp. 685-720.Australia, QueenslandGeochemistry, geochronology, Basalts
DS1982-0422
1982
Mcculloch, M.T.Mcculloch, M.T., Arculus, R.J., Chappell, B.W., Ferguson, J.Isotopic and Geochemical Studies of Nodules in Kimberlite Have Implications for the Lower Continental Crust.Nature., Vol. 300, No. 5888, Nov. 11, PP. 166-169.AustraliaCalcutteroo, Rare Earth Elements (ree), Xenolith, Geochemistry, Kimberlite
DS1983-0439
1983
Mcculloch, M.T.Mcculloch, M.T., Jaques, A.L., Nelson, D.R., Lewis, J.D.Neodymium and Strontium Isotopes in Kimberlites and Lamproites from western Australia and Enriched Mantle Origin.Nature., Vol. 302, No. 5907, PP. 400-403.AustraliaIsotope, Lamproite, Kimberlite, Petrology
DS1984-0546
1984
Mcculloch, M.T.Nelson, D.R., Crawford, A.J., Mcculloch, M.T.Neodymium-strontium Isotopic and Geochemical Systematics in Cambrian bonin Ites and Tholeites from Victoria, Australia.Contributions to Mineralogy and Petrology, Vol. 88, PP. 164-172.AustraliaBlank
DS1984-0547
1984
Mcculloch, M.T.Nelson, D.R., Mcculloch, M.T., Jaques, A.L.neodymium, Strontium isotope ratios in ultrapotassic rocks from southeast Australia and their implications from the subcontinental lithosphereIn: Geoscience in the development of Natural Resources Abstract Volume, Vol. 12, pp. 401-402AustraliaBlank
DS1984-0548
1984
Mcculloch, M.T.Nelson, D.R., Mcculloch, M.T., Jaques, A.L.Nd-sr Isotope Ratios in Ultrapotassic Rocks from Southeast Australia and Their Implications from the Subcontinental Lithosphere.Geological Society of Australia., No. 12, ABSTRACT VOLUME, PP. 401-402.Australia, Southeastern AustraliaGeochronology, Leucitite
DS1985-0430
1985
Mcculloch, M.T.Mcdonough, W.F., Mcculloch, M.T.Geochemical and Isotopic Systematics of Spinel Lherzolites from Southeast Australia.Eos, Vol. 66, No. 46, NOVEMBER 12, P. 1110. (abstract.).Australia, Southeast Australia, VictoriaGeochemistry
DS1985-0431
1985
Mcculloch, M.T.Mcdonough, W.F., Mcculloch, M.T., Sun, S.S.Isotopic and Geochemical Systematics in Tertiary Recent Basalts from Southeastern Australia and Implications for the Evolution of the Subcontinental Lithosphere.Geochimica et Cosmochimica ACTA., Vol. 49, No. 10, PP. 2051-2067.Australia, Southeast AustraliaPetrology, Basalt
DS1986-0548
1986
McCulloch, M.T.McCulloch, M.T.Samarium-neodymium (Sm-Nd) systematics in eclogite and garnet peridotite nodules fromkimberlites: implications for the early differentiation of the earth #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 285-287South Africa, RussiaEclogite
DS1986-0549
1986
McCulloch, M.T.McDonough, W.F., McCulloch, M.T.Chemical and isotopic evolution of the southeast AustraliansubcontinentallithosphereProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 288-290AustraliaGeochemistry
DS1986-0596
1986
McCulloch, M.T.Nelson, D.R., McCulloch, M.T., Ringwood, A.E.Ultrapotassic magmas: end products of subduction and mantle recycling ofsediments?Proceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 196-198Australia, Wyoming, MacRobertson Land, Enderby LandLamproite
DS1986-0597
1986
McCulloch, M.T.Nelson, D.R., McCulloch, M.T., Shen Su SunThe origins of ultrapotassic rocks as inferred from Strontium, neodymium, and lead isotopesGeochimica et Cosmochimica Acta, Vol. 50, No. 2, pp. 231-245AustraliaLachlan fold belt, Kimberley block, leucite basalt, Lamproite
DS1986-0789
1986
McCulloch, M.T.Sun, S.S., Jaques, A.L., McCulloch, M.T.Isotopic evolution of the Kimberley block, western AustraliaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 346-348AustraliaBlank
DS1987-0455
1987
McCulloch, M.T.McDonough, W.F., McCulloch, M.T.Growth and evolution of the subcrustal lithosphere: oceanic versuscontinentalTerra Cognita, Conference abstracts Oceanic and Continental Lithosphere:, Vol. 7, No. 4, Autumn, abstract only p. 619AustraliaBlank
DS1987-0456
1987
McCulloch, M.T.McDonough, W.F., McCulloch, M.T.The southeast Australian lithospheric mantle: isotopic and geochemical constraints on its growth and evolutionEarth and Planetary Science Letters, Vol. 86, pp. 327-340AustraliaBlank
DS1987-0509
1987
McCulloch, M.T.Nelson, D.R., McCulloch, M.T., Sun, S.S.The origins of ultrapotassic rocks as inferred from strontium neodymiumand lead isotopesGeochimica et Cosmochimica Acta, Vol. 50, pp. 231-245GlobalBlank
DS1988-0451
1988
McCulloch, M.T.McCulloch, M.T.Crust-mantle recycling: inputs and outputsCrust Mantle recycling at convergence zones, Editors, Hart, S.R., pp. 203-214GlobalMantle
DS1988-0503
1988
McCulloch, M.T.Nelson, D.R., Chivas, A.R., Chappell, B.W., McCulloch, M.T.Geochemical and isotopic systematics in carbonatites And implications For the evolution of ocean island sources (review)Geochimica et Cosmochimica Acta, Vol. 52, No. 1, January pp. 1-17GlobalBlank
DS1989-0280
1989
McCulloch, M.T.Collerson, K.D., McCulloch, M.T., Nutman, A.P.Strontium and neodymium isotope systematics of polymetamorphic Archean gneisses from southern West Greenland, LabradorCanadian Journal of Earth Sciences, Vol. 26, pp. 446-66.Greenland, LabradorGeochronology
DS1989-0981
1989
McCulloch, M.T.McCulloch, M.T.Samarium-neodymium (Sm-Nd) systematics in eclogite and garnet peridotite nodules fromkimberlites: implications for the early differentiation of the earth #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 864-876South AfricaEclogites, Nodules
DS1989-1106
1989
McCulloch, M.T.Nelson, D.R., Black, L.P., McCulloch, M.T.Neodymium-Palladium isotopic characteristics of the Mordor Complex, Northern Territory: Mid-Proterozoic potassic magmatism from an enriched mantle sourceAustralian Journal of Earth Sciences, Vol. 36, No. 4, December pp. 541-551AustraliaPotassic rocks, Proterozoic, Mordor Complex, Rare Earth Elements
DS1989-1107
1989
McCulloch, M.T.Nelson, D.R., McCulloch, M.T.Petrogenetic applications of the 40K -40Ca radiogenic decay scheme- are connaissance studyChemical Geology, Vol. 79, No. 4, Sept. 25, pp. 275-293Australia, SpainGeochronology, Petrology
DS1989-1108
1989
McCulloch, M.T.Nelson, D.R., McCulloch, M.T.Petrogenetic applications of the 40K-40Ca radiogenic decay scheme - are connaissance studyChemical Geology, Vol. 79, No. 4, September 25, pp. 275-293Australia, Spain, AntarcticaKimberlite, Geochronology
DS1989-1109
1989
McCulloch, M.T.Nelson, D.R., McCulloch, M.T.Enriched mantle components and mantle recycling of sedimentsGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 560-570GlobalMantle, Potassic enrichment
DS1990-1345
1990
McCulloch, M.T.Sheraton, J.W., Black, L.P., McCulloch, M.T., Oliver, R.L.Age and origin of a compositionally varied mafic dyke swarm in the Bunger Hills ,East AntarcticaChemical Geology, Vol. 85, No. 3/4, July 30, pp. 215-246AntarcticaMafic dyke, Picrite
DS1991-1100
1991
McCulloch, M.T.McCulloch, M.T., Gamble, J.A.Geochemical and geodynamical constraints on subduction zone magmatismEarth and Planetary Science Letters, Vol. 102, No. 3/4, March pp. 358-374GlobalGeochemistry, Mantle
DS1991-1599
1991
McCulloch, M.T.Sivell, W.J., McCulloch, M.T.Neodymium isotope evidence for ultra-depleted mantle in the earlyProterozoicNature, Vol. 354, No. 6352, December 5, pp. 384-386MantleGeochronology
DS1993-0106
1993
McCulloch, M.T.Bennett, V.C., Nutman, A.P., McCulloch, M.T.neodymium isotopic evidence for transient, highly depleted mantle reservoirs In the early history of the earthEarth and Planetary Science Letters, Vol. 119, No. 3, September pp. 299-318MantleGeochronology, magma
DS1993-0751
1993
McCulloch, M.T.Jian-xin Zhao, McCulloch, M.T.Melting of a subduction modified continental lithospheric mantle: evidence from Late Proterozoic mafic dike swarms in central AustraliaGeology, Vol. 21, No. 5, May pp. 463-466AustraliaDike, Subduction
DS1993-0994
1993
McCulloch, M.T.McCulloch, M.T.The role of subducted slabs in an evolving earthEarth and Planetary Science Letters, Vol. 115, No. 1-4, March pp. 89-101.MantleSubduction, Archean
DS1993-0995
1993
McCulloch, M.T.McCulloch, M.T.The role of subducted slabs in an evolving crustEarth and Planetary Science Letters, Vol. 115, No. 1-4, March pp. 89-100MantleTectonics, Subduction
DS1993-0996
1993
McCulloch, M.T.McCulloch, M.T., Bennett, V.C.Evolution of the early earth: constraints from 143 neodymium-142 neodymium isotopicsystematicsLithos, Vol. 30, No. 3-4, September pp. 237-256MantleGeochronology -evolution, Geodynamics
DS1993-1815
1993
McCulloch, M.T.Zhao, J.X., McCulloch, M.T.samarium-neodymium (Sm-Nd) mineral isochron ages of Late Proterozoic dyke swarms in Australia:evidence for two distinctive events of mafic magmatism and crustal extension.Chemical Geology, Vol. 109, pp. 341-354.AustraliaGeochronology, Dike swarms
DS1994-1143
1994
McCulloch, M.T.McCulloch, M.T.Primitive 87Sr and 86 Sr from an Archean barite and conjecture on theearth's age and originEarth and Planetary Science Letters, Vol. 126, No. 1-3, August pp. 1-14MantleGeochronology, Archean, strontium
DS1994-1144
1994
McCulloch, M.T.McCulloch, M.T., Bennett, V.C.Progressive growth of the earth's continental crust and depleted mantle:geochemical constraints.Geochimica et Cosmochimica Acta, Vol. 58, 21, pp. 4717-38.MantleGeochemistry, Model
DS1994-1988
1994
McCulloch, M.T.Zhao, J., McCulloch, M.T., Korsch, R.J.Characterisation of a plume related - 800 Ma magmatic event and its implications for basin formation in central -southern AustraliaEarth and Planetary Science Letters, Vol. 121, No. 3-4, February pp. 349-368AustraliaBasin formation, Hot spot
DS1996-0842
1996
McCulloch, M.T.Li, X., McCulloch, M.T.Secular variation in the neodymium isotopic composition of Neoproterozoic sediments from southern margin YangtzePrecambrian Research, Vol. 76, No. 1, 2, Jan. 1, pp. 67-76.ChinaGeochronology, Geodynamics, tectonics
DS1997-1284
1997
McCulloch, M.T.Young, D.N., Zhao, J.X., McCulloch, M.T.Geochemical and Strontium-neodymium isotopic mapping of source provinces for the Mawson charnockites..Precambrian Research, Vol. 86, No. 1/2, Dec. 15, pp. 1-20AntarcticaTectonics - Proterozoic, Gondwana
DS200412-0021
2004
McCulloch, M.T.Altherr, R., Meyer, H.P., Holl, A., Volker, F., Alibert, C., McCulloch, M.T., Majer, V.Geochemical and Sr Nd Pb isotopic characteristics of Late Cenozoic leucite lamproites from the East European Alpine belt ( MacedContributions to Mineralogy and Petrology, Vol. 147, 1, pp. 58-73.Europe, MacedoniaLamproite, geodynamics
DS200612-0541
2006
McCulloch, M.T.Harrison, T.M., McCulloch, M.T., Blichert-Toft, J., Albarede, F., Holden, P., Mojzsis, S.J.Further Hf isotope evidence for Hadean continental crust.Geochimica et Cosmochimica Acta, Vol. 70, 18, 1, p. 14, abstract only.MantleGeochronology
DS200812-0448
2008
McCulloch, M.T.Harrison, T.M., Schmitt, A.K., McCulloch, M.T., Lovera, O.M.Evidence of crust during the first 100 m.y. of Earth's history: Lu-Hf, delta18 O, and Ti thermometry results for Hadean zircons.Goldschmidt Conference 2008, Abstract p.A355.MantleGeochronology
DS1989-1086
1989
McCulloch, T.H.Naeser, N.D., McCulloch, T.H.Thermal history of sedimentary basins- methods and case historiesSpringer-Verlag, 312p. ISBN 3-540-96702-8GlobalBook -Thermal history, Table of contents
DS200612-0085
2006
McCullock, L.Barnes, C.G., Li, Y., Barnes, M., McCullock, L., Frost, C., Prestvik, T., Allen, C.Carbonate assimilation in the alkaline Hortavaer igneous complex, Norway.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1. abstract only.Europe, NorwayCarbonatite
DS1984-0684
1984
Mcculloh, R.P.Snead, J.I., Mcculloh, R.P.Geologic Map of LouisianaLousiana Geological Survey, MAP 1: 500, 000GlobalGeology, Mid Continent
DS1990-0482
1990
McCullough, J.R.Folger, D.W., Irwin, B.J., McCullough, J.R., Rowland, R.W., PolloniMap showing free-air gravity anomalies off the southern coast of west-central Africa; Liberia to GhanaUnited States Geological Survey (USGS) Map, MF 2098-E, 1: 500, 000 $ 1.50GlobalGeophysics -gravity, Coast
DS1990-0483
1990
McCullough, J.R.Folger, D.W., Irwin, B.J., McCullough, J.R., Rowland, R.W., PolloniMap showing free air gravity anomalies off the southern coast of west central Africa: Liberia to GhanaUnited States Geological Survey (USGS) Map, No. MF-2098-E 1: 500, 000 $ 1.50West AfricaGravity, Map, Geophysics
DS1998-0845
1998
McCurdyLeckie, D.A., Nadon, Spirito, McCurdy, FriskeEvolution of fluvial landscapes in the Western Canada Foreland Basin; Late Jurassic to the modern...Geological Survey of Canada Open File, No. 2369Alberta, Northwest TerritoriesGeochemistry - regional stream sediment
DS1999-0458
1999
McCurdy, M.W.McCurdy, M.W., Anglin, C.D., Spirito, W.A., Eddy, B.Geochemical surveys and interpretation. Briefly mentions diamondGeological Survey of Canada (GSC) Open File, No. 3714, pp. D1-34.. $ 50.00Northwest Territories, Nunavut, Bathurst IslandGeochemistry
DS200412-1265
2004
McCurdy, M.W.McCurdy, M.W., et al.Preliminary release of geochemistry, mineralogy, kimberlite indicator mineral electron microprobe data- silts, heavy minerals, wGeological Survey of Canada Open File, No. 4735 National Geochemical Reconnaissance Stream SedCanada, AlbertaGeochemistry NTS 84F,G,K, 1 CD $ 26.
DS200612-0319
2006
McCurdy, M.W.Day, S.J.A., Lariviere, J.M., Friske, P.W.B., McNeil, R.J., McCurdy, M.W.National geochemical Reconnaissance: regional stream sediment and water data: Travaillant Lake area.. analytical, mineralogical kimberlite indicator dataGeological Survey of Canada Open File, 4951, 1 CD May 17, $ 9.10Canada, Northwest TerritoriesGeochemistry - NTS 106N part of 106O
DS200612-1113
2006
McCurdy, M.W.Prior, G.J., McCurdy, M.W., Friske, P.W.B., Pawlowicz, S.J.A.,Day, R.J.Mc.Preliminary release of kimberlite indicator mineral dat a from National geochemical Reconnaissance stream sediment samples in the Jackpine Lake area Buffalo Head HillsGeological Survey of Canada Open File, 5267, 23p. 1 CD $ 26.00Canada, AlbertaGeochemistry
DS200712-0705
2006
McCurdy, M.W.McCurdy, M.W., Prior, G.J., Friske, P.W.B., McNeil, R.J., Day, S.J.A., Nicholl, T.J.Geochemical, mineralogical and kimberlite indicator mineral electron microprobe dat a from sills, heavy mineral concentrates and waters Buffalo Head Hills.Geological Survey of Canada Open File, No. 5057, 16p.Canada, AlbertaGeochemistry
DS201012-0600
2009
McCurdy, M.W.Prior, G.J., McCurdy, M.W., Friske, P.W.B.Stream sediment sampling for kimberlite indicator minerals in the western Canada sedimentary basin: the Buffalo Head Hills Survey, north central Alberta.Geological Association of Canada Short Course, No. 18, pp. 111-124.Canada, AlbertaGeochemistry, technology
DS1989-0058
1989
McCurry, M.Bahar, D., McCurry, M.Maar deposits at Kilbourne Hole: implications for base surge processesNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 11 Abstract held June 25-July 1New MexicoVolcanology
DS1960-1231
1969
Mccurry, P.Wright, J.B., Mccurry, P.Note on Atlantic Fracture Zones and the Guinea CoastMining Geology (japan), Vol. 65, No. 1-2, PP.West Africa, GuineaTectonics, Structure
DS1860-0268
1876
Mccutcheon, A.R.Mccutcheon, A.R.Geological Survey of the StateHandbook of The State of Georgia., ATLANTA: NEW YORK CITY: RUSSELL BROS., 256P.United States, GeorgiaDiamond Occurrence
DS1997-1188
1997
McCutcheon, S.Vallee, M., McCutcheon, S.Are international reporting standards feasible?The Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 90, No. 1007, Feb. pp. 30-37GlobalGeostatistics, Economics, ore reserves, resources, terminology
DS1990-0421
1990
McCutcheon, S.R.Dostal, J., McCutcheon, S.R.Geochemistry of Late Proterozoic basaltic rocks from southeastern NewBrunswick, CanadaPrecambrian Research, Vol. 47, No. 1-2, April pp. 83-98New BrunswickGeochemistry, Basalt
DS200412-1912
2004
McDada, P.Stachel, T., Vijoen, K.S., McDada, P., Harris, J.W.Survival of diamonds during major tectonothermal events - peridotitic inclusions in diamonds from Orapa and Jwaneng.Geological Association of Canada Abstract Volume, May 12-14, SS14-13 p. 272.abstractAfrica, BotswanaGeochemistry - major element
DS1998-0976
1998
McDade, P.McDade, P., Harris, J.W.Syngenetic inclusion bearing diamonds from Letseng la Terai, Lesotho7th International Kimberlite Conference Abstract, pp. 561-3.LesothoDiamond inclusions, Deposit - Letseng
DS1999-0459
1999
McDade, P.McDade, P., Harris, J.W.Syngenetic inclusion bearing diamonds from Letseng la Terai Lesotho7th International Kimberlite Conference Nixon, Vol. 2, pp. 557-65.LesothoDiamond - inclusions, Deposit - Letseng la Terai
DS2003-0908
2003
McDade, P.McDade, P., Blundy, J.D., Wood, B.J.Trace element partitioning between mantle wedge peridotite and hydrous MgO richAmerican Mineralogist, Vol. 88, pp. 1825-31.Mantle, AntillesSlab, subduction, LILE
DS200412-1266
2003
McDade, P.McDade, P., Blundy, J.D., Wood, B.J.Trace element partitioning between mantle wedge peridotite and hydrous MgO rich melt.American Mineralogist, Vol. 88, pp. 1825-31.Mantle, AntillesSlab, subduction, LILE
DS200412-1913
2004
McDade, P.Stachel, T., Viljoen, K.S., McDade,P.,Harris, J.W.Diamondiferous lithospheric roots along the western margin of the Kalahari Craton - the peridotitic inclusion suites in diamondsContributions to Mineralogy and Petrology, Vol. 147, 1, pp. 32-47.Africa, BotswanaDiamond genesis, Orapa, Jwaneng deposits
DS1975-0133
1975
Mcdaid, J.M.Mcdaid, J.M.Preliminary Report on the Geology of the Northern Part of Diamond Area No. 1, Southwest Africa.Cape Town University Precambrian Research Unit Annual Report, Vol. 13, PP. 94-96.Southwest Africa, NamibiaGeology
DS1975-0806
1978
Mcdaid, J.M.Mcdaid, J.M.The Geology of the Northern Part of Diamond Area No. 1, South West Africa in 1976 and 1977.Cape Town University Precambrian Research Unit Annual Report, Vol. 14-15, PP. 124-140.Southwest Africa, NamibiaGeology, Submarine Diamond Placers
DS201805-0962
2018
McDannell, K.T.McDannell, K.T., Zeitler, P.K., Schneider, D.A.Instability of the southern Canadian Shield during the late Proterozoic.Earth Planetary Science Letters, Vol. 490, pp. 100-109.Canadacraton

Abstract: Cratons are generally considered to comprise lithosphere that has remained tectonically quiescent for billions of years. Direct evidence for stability is mainly founded in the Phanerozoic sedimentary record and low-temperature thermochronology, but for extensive parts of Canada, earlier stability has been inferred due to the lack of an extensive rock record in both time and space. We used 40Ar/39Ar multi-diffusion domain (MDD) analysis of K-feldspar to constrain cratonic thermal histories across an intermediate (~150-350°C) temperature range in an attempt to link published high-temperature geochronology that resolves the timing of orogenesis and metamorphism with lower-temperature data suited for upper-crustal burial and unroofing histories. This work is focused on understanding the transition from Archean-Paleoproterozoic crustal growth to later intervals of stability, and how uninterrupted that record is throughout Earth’s Proterozoic "Middle Age." Intermediate-temperature thermal histories of cratonic rocks at well-constrained localities within the southern Canadian Shield of North America challenge the stability worldview because our data indicate that these rocks were at elevated temperatures in the Proterozoic. Feldspars from granitic rocks collected at the surface cooled at rates of <0.5°C/Ma subsequent to orogenesis, seemingly characteristic of cratonic lithosphere, but modeled thermal histories suggest that at ca. 1.1-1.0 Ga these rocks were still near ~200°C - signaling either reheating, or prolonged residence at mid-crustal depths assuming a normal cratonic geothermal gradient. After 1.0 Ga, the regions we sampled then underwent further cooling such that they were at or near the surface (<< 60°C) in the early Paleozoic. Explaining mid-crustal residence at 1.0 Ga is challenging. A widespread, prolonged reheating history via burial is not supported by stratigraphic information, however assuming a purely monotonic cooling history requires at the very least 5 km of exhumation beginning at ca. 1.0 Ga. A possible explanation may be found in evidence of magmatic underplating that thickened the crust, driving uplift and erosion. The timing of this underplating coincides with Mid-Continent extension, Grenville orogenesis, and assembly of the supercontinent Rodinia. 40Ar/39Ar MDD data demonstrate that this technique can be successfully applied to older rocks and fill in a large observational gap. These data also raise questions about the evolution of cratons during the Proterozoic and the nature of cratonic stability across deep time.
DS201810-2354
2018
McDannell, K.T.McDannell, K.T., Zeitler, P.K., Schneider, D.A.Instability of the southern Canadian shield during the Late Proterozoic.researchgate.com, 29p. PdfCanadacraton

Abstract: Cratons are generally considered to comprise lithosphere that has remained tectonically quiescent for billions of years. Direct evidence for stability is mainly founded in the Phanerozoic sedimentary record and low-temperature thermochronology, but for extensive parts of Canada, earlier stability has been inferred due to the lack of an extensive rock record in both time and space. We used 40Ar/39Ar multi-diffusion domain (MDD) analysis of K-feldspar to constrain cratonic thermal histories across an intermediate (?150-350?°C) temperature range in an attempt to link published high-temperature geochronology that resolves the timing of orogenesis and metamorphism with lower-temperature data suited for upper-crustal burial and unroofing histories. This work is focused on understanding the transition from Archean-Paleoproterozoic crustal growth to later intervals of stability, and how uninterrupted that record is throughout Earth's Proterozoic “Middle Age.” Intermediate-temperature thermal histories of cratonic rocks at well-constrained localities within the southern Canadian Shield of North America challenge the stability worldview because our data indicate that these rocks were at elevated temperatures in the Proterozoic. Feldspars from granitic rocks collected at the surface cooled at rates of <0.5?°C/Ma subsequent to orogenesis, seemingly characteristic of cratonic lithosphere, but modeled thermal histories suggest that at ca. 1.1-1.0 Ga these rocks were still near ?200?°C - signaling either reheating, or prolonged residence at mid-crustal depths assuming a normal cratonic geothermal gradient. After 1.0 Ga, the regions we sampled then underwent further cooling such that they were at or near the surface (?60?°C) in the early Paleozoic. Explaining mid-crustal residence at 1.0 Ga is challenging. A widespread, prolonged reheating history via burial is not supported by stratigraphic information, however assuming a purely monotonic cooling history requires at the very least 5 km of exhumation beginning at ca. 1.0 Ga. A possible explanation may be found in evidence of magmatic underplating that thickened the crust, driving uplift and erosion. The timing of this underplating coincides with Mid-Continent extension, Grenville orogenesis, and assembly of the supercontinent Rodinia. 40Ar/39Ar MDD data demonstrate that this technique can be successfully applied to older rocks and fill in a large observational gap. These data also raise questions about the evolution of cratons during the Proterozoic and the nature of cratonic stability across deep time.
DS202012-2230
2020
McDannell, K.T.McDannell, K.T., Flowers, R.M.Vestiges of the ancient: deep-time noble gas thermochronology.Elements, Vol. 16, pp. 325-330.Canada, Nunavut, Southampton Island, Africa, Kaapvaalcraton

Abstract: Ancient rocks have survived plate tectonic recycling for billions of years, but key questions remain about how and when they were exhumed to the surface. Constraining exhumation histories over long timescales is a challenge because much of the rock record has been lost to erosion. Argon and helium noble gas thermochronology can reconstruct deep-time <350 °C thermal histories by using the distinct temperature sensitivities of minerals such as feldspar, zircon, and apatite, while exploiting grain size and radiation damage effects on diffusion kinetics. Resolution of unique time-temperature paths over long timescales requires multiple chronometers, appropriate kinetic models, and inverse simulation techniques to fully explore and constrain possible solutions. Results suggest that surface histories of ancient continental interiors are far from uninteresting and may merely be misunderstood.
DS1994-0745
1994
McDermottHawkesworth, C.J., Gallagher, K., Hergt, J.M., McDermottDestructive plate margin magmatism: geochemistry and melt generationLithos, Vol. 33, No. 1-3, October pp. 169-188.MantleGeotectonics, geodynamics, Geochemistry
DS1989-0982
1989
McDermott, F.McDermott, F., Harris, N.B.W., Hawkesworth, C.J.Crustal reworking in southern Africa: constraints from Sr-neodymium isotope studies in Archean to Pan-AfricanterrainsTectonophysics, Vol. 161, No. 3/4, pp. 257-270South AfricaGeochronology, Tectonics
DS1990-0442
1990
McDermott, F.Ellam, R.M., Hawkesworth, C.J., McDermott, F.lead isotope dat a from late Proterozoic subduction related rocks:implications for crust-mantle evolutionChem. Geol, Vol. 83, No. 3/4, June 25, pp. 165-181Saudi ArabiaMantle, Geochronology
DS1990-1006
1990
McDermott, F.McDermott, F., Hawkesworth, C.The evolution of strontium isotopes in the upper continental crustNature, Vol. 344, No. 6269, April 26, pp. 850-853GlobalMantle, Geochronology
DS1991-0687
1991
McDermott, F.Hawkesworth, C.J., Hergt, J.M., Ellam, R.M., McDermott, F.Element fluxes associated with subduction related magmatismPhil. Transactions R. Soc. London, Sect. A., Vol. 335, pp. 393-405GlobalGeochemistry -rare earths, Isotopes
DS1991-0688
1991
McDermott, F.Hawkesworth, C.J., Hergt, J.M., McDermott, F., Ellam, R.M.Destructive margin magmatism and the contributions from the mantle wEdge and subducted crustAustralian Journal of Earth Sciences, Vol. 38, December pp. 577-594AustraliaMantle, Subduction
DS1993-0644
1993
McDermott, F.Hawkesworth, C.J., Gallagher, K., Hergt, J.M., McDermott, F.Trace element fractionation processes in the generation of island arcbasaltsRoyal Society Transactions, Physical Sciences, Ser. A, Vol. 342, No. 1663, January 15, pp. 179-191MantleSubduction, Magmas
DS1993-0645
1993
McDermott, F.Hawkesworth, K., Gallagher, K., Hergt, J.M., McDermott, F.Mantle and slab contribution in arc magmasAnnual Review of Earth and Planetary Sciences, Vol. 21, pp. 175-204MantleSubduction, Tectonics
DS1997-0585
1997
McDermott, F.Kepezhinskas, P., McDermott, F., et al.Trace element and Strontium, neodymium, lead isotopic constriants on a three component model of Kamchatka Arc petrogenesis.Geochimica Et Cosmochimica Acta, Vol. 61, No. 3, pp. 577-600.RussiaGeochemistry, Geochronology
DS1993-1525
1993
McDermott, J.Steels, L., McDermott, J.The knowledge level in expert systemsAcademic Press, 288p. approx. $ 50.00GlobalBook -ad, Expert systems
DS202104-0589
2021
McDermott, J.Lollar, B.S., Heuer, V.B., McDermott, J., Tille, S., Warr, O., Moran, J.J., Telling, J., Hinrichs, K-U.A window into the abiotic carbon cycle - acetate and formate in fracture waters in 2.7 billion year-old host rocks of the Canadian shield. ( Not specific to diamonds just interest)Geochimica et Cosmochimica Acta, Vol. 294. pp. 295-314. pdfCanadacarbon

Abstract: The recent expansion of studies at hydrothermal submarine vents from investigation of abiotic methane formation to include abiotic production of organics such acetate and formate, and rising interest in processes of abiotic organic synthesis on the ocean-world moons of Saturn and Jupiter, have raised interest in potential Earth analogs for investigation of prebiotic/abiotic processes to an unprecedented level. The deep continental subsurface provides an attractive target to identify analog environments where the influence of abiotic carbon cycling may be investigated, particularly in hydrogeological isolated fracture fluids where the products of chemical water-rock reactions have been less overprinted by the biogeochemical signatures of the planet’s surficial water and carbon cycles. Here we report, for the first time, a comprehensive set of concentration measurements and isotopic signatures for acetate and formate, as well as the dissolved inorganic and organic carbon pools, for saline fracture waters naturally flowing 2.4?km below surface in 2.7 billion year-old rocks on the Canadian Shield. These geologically ancient fluids at the Kidd Creek Observatory were the focus of previous investigations of fracture fluid geochemistry, microbiology and noble gas-derived residence times. Here we show the fracture waters of Kidd Creek contain high concentrations of both acetate and formate with concentrations from 1200 to 1900?µmol/L, and 480 to 1000?µmol/L, respectively. Acetate and formate alone account for more than 50-90% of the total DOC - providing a very simple "organic soup". The unusually elevated concentrations and profoundly 13C-enriched nature of the acetate and formate suggest an important role for abiotic organic synthesis in the deep carbon cycle at this hydrogeologically isolated site. A variety of potential abiotic production reactions are discussed, including a radiolytically driven H, S and C deep cycle that could provide a mechanism for sustaining deep subsurface habitability. Scientific discoveries are beginning to reveal that organic-producing reactions that would have prevailed on Earth before the rise of life, and that may persist today on planets and moons such as Enceladus, Europa and Titan, can be accessed in some specialized geologic settings on Earth that provide valuable natural analog environments for the investigation of abiotic organic chemistry outside the laboratory.
DS1960-0800
1967
Mcdermott, V.J.Brookins, D.G., Mcdermott, V.J.Age and Temperature of Intrusions of Kimberlite, Riley County, Kansas.Geological Society of America (GSA) SPECIAL PAPER., No. 115, P. 336, (abstract.).KansasKimberlite, Central States
DS1970-0037
1970
Mcdermott, V.J.Brookins, D.G., Mcdermott, V.J.The Mineralogy of the Randolph Kimberlite, Riley County, Kansas.Kansas Academy of Science Transactions, Vol. 73, No. 1, PP. 31-39.KansasKimberlite, Central States
DS1860-0902
1895
Mcdermott, W.Mcdermott, W.Mining Reports and Mine SaltingInstitute of Mining and Metallurgy. Transactions, Vol. 3, PP. 108-149.Africa, South AfricaMining recovery, legal
DS1900-0032
1900
Mcdermott, W.Mcdermott, W.Use of Grease in the Recovery of Diamonds. In: Discussion Of the Elmore Process, a Talk by Rolker.Institute of Mining and Metallurgy. Transactions, Vol. 8, P. 391.Africa, South AfricaDiamond Recovery, Grease Belt, Mining Engineering
DS1960-1166
1969
Mcdermott, W.J.Mcdermott, W.J.Determinative Mineralogy of the Randolph Intrusion, Riley County, kansas.Msc. Thesis, Kansas State University, 77P.GlobalKimberlite, Mineralogy
DS201212-0453
2011
McDiarmid, N.McDiarmid, N.Moving the goal posts - cracking the code Australian Securities Exchange listing rules change.ResourcesStocks.com, December pp. 64,65,67,69.AustraliaNews item - JORC
DS1990-1007
1990
McDivitt, J.McDivitt, J., LockSmall scale mining: a guide to appropriate equipmentInternational Tech. Publications, 103-105 Southampton Row, London WC1B 4HH 12.50 lbsGlobalMining, Small scale equipment guide
DS201805-0948
2018
McDivitt, J.A.Greenough, J.D., McDivitt, J.A.Earth's evolving subcontinental lithospheric mantle: inferences from LIP continental flood basalt geochemistry.International Journal of Earth Sciences, Vol. 107, 3, pp. 787-810.Mantlegeochemistry

Abstract: Archean and Proterozoic subcontinental lithospheric mantle (SLM) is compared using 83 similarly incompatible element ratios (SIER; minimally affected by % melting or differentiation, e.g., Rb/Ba, Nb/Pb, Ti/Y) for >3700 basalts from ten continental flood basalt (CFB) provinces representing nine large igneous provinces (LIPs). Nine transition metals (TM; Fe, Mn, Sc, V, Cr, Co, Ni, Cu, Zn) in 102 primitive basalts (Mg# = 0.69-0.72) from nine provinces yield additional SLM information. An iterative evaluation of SIER values indicates that, regardless of age, CFB transecting Archean lithosphere are enriched in Rb, K, Pb, Th and heavy REE(?); whereas P, Ti, Nb, Ta and light REE(?) are higher in Proterozoic-and-younger SLM sources. This suggests efficient transfer of alkali metals and Pb to the continental lithosphere perhaps in association with melting of subducted ocean floor to form Archean tonalite-trondhjemite-granodiorite terranes. Titanium, Nb and Ta were not efficiently transferred, perhaps due to the stabilization of oxide phases (e.g., rutile or ilmenite) in down-going Archean slabs. CFB transecting Archean lithosphere have EM1-like SIER that are more extreme than seen in oceanic island basalts (OIB) suggesting an Archean SLM origin for OIB-enriched mantle 1 (EM1). In contrast, OIB high U/Pb (HIMU) sources have more extreme SIER than seen in CFB provinces. HIMU may represent subduction-processed ocean floor recycled directly to the convecting mantle, but to avoid convective homogenization and produce its unique Pb isotopic signature may require long-term isolation and incubation in SLM. Based on all TM, CFB transecting Proterozoic lithosphere are distinct from those cutting Archean lithosphere. There is a tendency for lower Sc, Cr, Ni and Cu, and higher Zn, in the sources for Archean-cutting CFB and EM1 OIB, than Proterozoic-cutting CFB and HIMU OIB. All CFB have SiO2 (pressure proxy)-Nb/Y (% melting proxy) relationships supporting low pressure, high % melting resembling OIB tholeiites, but TM concentrations do not correlate with % melting. Thus, the association of layered intrusion (plutonic CFB) TM deposits with Archean terranes does not appear related to higher metal concentrations or higher percentages of melting in Archean SLM. Other characteristics of these EM1-like magmas (e.g., S2 or O2 fugacity) may lead to element scavenging and concentration during differentiation to form ore deposits.
DS2000-0133
2000
McDonaldByron, M.J., Gibson, Watkinson, Whitehead, McDonaldExtraordinary accessory minerals of the Mat a Da Corda Formation: implications for rock type classificationGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Calgary May 2000, 5p.BrazilPetrology, mineralogy, exploration, diamond, igneous, Mata Da Corda Formation
DS2001-0006
2001
McDonaldAgashev, A.M., Pokhilenko, McDonald, Takazawa, VavilovA unique kimberlite carbonatite primary association in the Snap lake dyke system: evidence from geochemical..Slave-Kaapvaal Workshop, Sept. Ottawa, 2p. abstractNorthwest TerritoriesGeochemistry, geochronology, Slave Craton, Deposit - Snap Lake
DS2001-0934
2001
McDonaldPokhilenko, N.P., McDonald, Hall, SobolevAbnormally thick Cambrian lithosphere of the southeast Slave Craton evidence from crystalline inclusions ..Slave-Kaapvaal Workshop, Sept. Ottawa, 3p. abstractNorthwest TerritoriesDiamonds and pyrope compositions - kimberlites, Deposit - Snap Lake
DS2001-0935
2001
McDonaldPokhilenko, N.P., Sobolev, McDonald, Hall, YefimovaCrystalline inclusions in diamonds from kimberlites of the Snap lake area: new evidence anomalous lithosphereDoklady Academy of Sciences, Vol. 381, No. 7, Sept/Oct. pp. 806-11.Northwest TerritoriesDiamond - inclusions, Deposit - Snap Lake
DS2001-0936
2001
McDonaldPokhilenko, N.P., Sobolev, N.V., McDonald, Hall et alCrystalline inclusions in diamonds from kimberlites of the Snap lake: new evidence anomalous lithosphericDoklady Academy of Sciences, Vol. 380, No. 7, Sept-Oct. pp.806-12.Northwest TerritoriesDiamond - inclusions, Deposit - Snap lake
DS201012-0482
2010
McDonald, A.M.McDonald, A.M., Chao, G.Y.Rogermitchellite, a new mineral species from Mont Hilaire Quebec: description, structure, determination and relationship with HFSE bearing cyclosilicates.Canadian Mineralogist, Vol. 48, 2, pp. 267-278.Canada, QuebecAlkalic
DS201707-1303
2017
McDonald, A.M.Ames, D.E., Kjarsgaard, I.M., McDonald, A.M., Good, D.J.Insights into the extreme PGE enrichment of the W Horizon, Marathon Cu-Pd deposit, Coldwell alkaline complex, Canada: platinum group mineralogy, compositions and genetic implications.Ore Geology Reviews, in press availableCanada, Ontarioalkaline - Coldwell Complex

Abstract: The W Horizon, Marathon Cu-Pd deposit in the Mesoproterozoic Midcontinent rift is one of the highest grade PGE repositories in magmatic ore deposits world-wide. The textural relationships and compositions of diverse platinum-group mineral (PGM) and sulfide assemblages in the extremely enriched ores (>100 ppm Pd-Pt-Au over 2 m) of the W Horizon have been investigated in mineral concentrates with ?10,000 PGM grains and in situ using scanning electron microprobe and microprobe analyses. Here we show, from ore samples with concentrations up to 23.1 Pd ppm, 8.9 Pt ppm, 1.4 Au ppm and 0.73 Rh ppm, the diversity of minerals (n = 52) including several significant unknown minerals and three new mineral species marathonite (Pd25Ge9; McDonald et al., 2016), palladogermanide (Pd2Ge; IMA 2016-086, McDonald et al., 2017), kravtsovite (PdAg2S, IMA No 2016-092, Vymazalová et al., 2017). The PGM are distributed as PG-, sulfides (52 vol%), -arsenides (34 vol%), -intermetallics of Au-Ag-Pd-Cu and Pd-Ge(10 vol%) and -bismuthides and tellurides (4 vol%). The discovery of abundant (>330 grains) large unknown sulfide minerals with Rh allows us to present analyses three significant potentially new minerals (WUK-1, WUK-2, WUK-3) that are all clearly enriched in Rh (averaging 4.2, 8.5 and 28.21 wt% Rh respectively). Several examples of paragenetic sequences and mineral chemical changes for enrichment of Cu, Pd and Rh with time are revealed in the PGM and base-metal sulfides. We suggest this enhanced metal enrichment formed in response to increasing fO2 causing the oxidation of Fe2+ to Fe3+ and to a lesser extent, S. Phase relations in the Ag-Pd-S, Rh-Ni-Fe-S, Pd-Ge, Au-Pd-Cu-Ag, Pd-Ag-Te systems help constrain the crystallization temperatures of the majority of ore minerals in the W Horizon at ?500 °C or moderate to high subsolidus temperatures (400–600 °C). Local transport by aqueous fluids becomes evident as minerals recrystallize down to <300 °C. The PGE-enriched W Horizon ores exhibit a complex post-magmatic history dominated by the effects of oxidation during cooling of a Cu-PGE enriched magma source from a deep reservoir.
DS201012-0484
2010
McDonald, B.McInnes, B., Evans, N., McDonald, B., Thern, E., Corbett, D.U Th Pb He double dating of zircon from the Diamondiferous Ellendale lamproite pipe, western Australia.Goldschmidt 2010 abstracts, abstractAustraliaDeposit - Ellendale
DS201212-0191
2012
McDonald, B.Evans, N.J., McInnes, B.I.A., McDonald, B., Danisik, M., Jourdan, F., Mayers, C., Thern, E., Corbett, D.Emplacement age and thermal footprint of the Diamondiferous Ellendale E9 lamproite pipe, Western Australia.Mineralium Deposita, in press availableAustraliaDeposit - Ellendale E9
DS201212-0192
2012
McDonald, B.Evans, N.J., McInnes, B.I.A., McDonald, B., Danisik, M., Jourdan, F., Mayers, C., Thern, E., Corbett, D.Emplacement age and thermal footprint of the Diamondiferous Ellendale E9 lamproite pipe, western Australia.Mineralium Deposita, in press availableAustraliaDeposit - Ellendale E9
DS201212-0456
2012
McDonald, B.McInnis, B., Evans, N., Jourdan, F., McDonald, B., Gorter, J., Mayers, C., Wilde, S.A Tertiary record of Australian plate motion from ages of Diamondiferous alkalic intrusions.Goldschmidt Conference 2012, abstract 1p.AustraliaGeochronology - Fohn
DS201312-0252
2013
McDonald, B.Evans, N.J., McInnies, B.I.A., McDonald, B., Danisik, M., Jourdan, F., Mayers, C., Thern, E., Corbett, D.Emplacement age and thermal footprint of the Diamondiferous Ellendale E9 lamproite pipe, western Australia.Mineralium Deposita, Vol. 48, 3, pp. 413-421.AustraliaDeposit - Ellendale 9
DS200912-0489
2009
McDonald, B.J.McInnes, B.I.A., Evans, N.J., McDonald, B.J., Kinny, P.D., Jakimowicz, J.Zircon U Th Pb He double dating of the Merlin kimberlite field, Northern Territory, Australia.Lithos, In press availableAustraliaDeposit - Merlin
DS201212-0455
2012
McDonald, B.J.McInnes, B.I.A., Evans, N.J., Jourdan, F., McDonald, B.J., Danislk, M., Mayers, C.Zircon U-TH-PB-HE double dating of North Australian diamond fields: Ellendale(WA) Seppelt ( WA) Merlin (NT).10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAustraliaDeposit - Ellendale, Seppelt, Merlin
DS202009-1673
2020
McDonald, B.J.Volante, S., Pouteau, A., Collins, W.J., Blereau, E., Li, Z-X., Smit, M., Evans, N.J., Nordsvan, A.R., Spencer, C.J., McDonald, B.J., Li, J., Gunter, C.Multiple P-T-d-t paths reveal the evolution of the final Nuna assembly in northeast Australia. Georgetown InlierJournal of Metamorphic Geology, Vol. 38, pp. 593-627.Australiageochronology

Abstract: The final assembly of the Mesoproterozoic supercontinent Nuna was marked by the collision of Laurentia and Australia at 1.60 Ga, which is recorded in the Georgetown Inlier of NE Australia. Here, we decipher the metamorphic evolution of this final Nuna collisional event using petrostructural analysis, major and trace element compositions of key minerals, thermodynamic modelling, and multi?method geochronology. The Georgetown Inlier is characterised by deformed and metamorphosed 1.70-1.62 Ga sedimentary and mafic rocks, which were intruded by c. 1.56 Ga old S?type granites. Garnet Lu-Hf and monazite U-Pb isotopic analyses distinguish two major metamorphic events (M1 at c. 1.60 Ga and M2 at c. 1.55 Ga), which allows at least two composite fabrics to be identified at the regional scale—c. 1.60 Ga S1 (consisting in fabrics S1a and S1b) and c. 1.55 Ga S2 (including fabrics S2a and S2b). Also, three tectono?metamorphic domains are distinguished: (a) the western domain, with S1 defined by low?P (LP) greenschist facies assemblages; (b) the central domain, where S1 fabric is preserved as medium?P (MP) amphibolite facies relicts, and locally as inclusion trails in garnet wrapped by the regionally dominant low?P amphibolite facies S2 fabric; and (c) the eastern domain dominated by upper amphibolite to granulite facies S2 foliation. In the central domain, 1.60 Ga MP-medium?T (MT) metamorphism (M1) developed within the staurolite-garnet stability field, with conditions ranging from 530-550°C at 6-7 kbar (garnet cores) to 620-650°C at 8-9 kbar (garnet rims), and it is associated with S1 fabric. The onset of 1.55 Ga LP-high?T (HT) metamorphism (M2) is marked by replacement of staurolite by andalusite (M2a/D2a), which was subsequently pseudomorphed by sillimanite (M2b/D2b) where granite and migmatite are abundant. P-T conditions ranged from 600 to 680°C and 4-6 kbar for the M2b sillimanite stage. 1.60 Ga garnet relicts within the S2 foliation highlight the progressive obliteration of the S1 fabric by regional S2 in the central zone during peak M2 metamorphism. In the eastern migmatitic complex, partial melting of paragneiss and amphibolite occurred syn? to post? S2, at 730-770°C and 6-8 kbar, and at 750-790°C and 6 kbar, respectively. The pressure-temperature-deformation-time paths reconstructed for the Georgetown Inlier suggest a c. 1.60 Ga M1/D1 event recorded under greenschist facies conditions in the western domain and under medium?P and medium?T conditions in the central domain. This event was followed by the regional 1.56-1.54 Ga low?P and high?T phase (M2/D2), extensively recorded in the central and eastern domains. Decompression between these two metamorphic events is ascribed to an episode of exhumation. The two?stage evolution supports the previous hypothesis that the Georgetown Inlier preserves continental collisional and subsequent thermal perturbation associated with granite emplacement.
DS1995-1207
1995
McDonald, D.McDonald, D., Poulin, R.Gainsharing, incentive plans and mining: an introductionThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 88, No. 988, March pp. 92-94CanadaMining -bonus plans
DS2003-0909
2003
McDonald, D.McDonald, D.Committee Bay project - the emerging story. ( brief mention of diamond)31st Yellowknife Geoscience Forum, p. 64. (abst.)NunavutMapping
DS200412-1267
2003
McDonald, D.McDonald, D.Committee Bay project - the emerging story. ( brief mention of diamond).31st Yellowknife Geoscience Forum, p. 64. (abst.)Canada, NunavutMapping
DS200412-1268
2004
McDonald, D.McDonald, D.The diamond frontier- from bleak and barren to bling-bling - how a growing industry is changing Canada's northern communities.Time Magazine, Canadian Edition, April 5, pp. 49-55.Canada, Northwest TerritoriesNews item - diamonds
DS1910-0368
1913
Mcdonald, D.P.Mcdonald, D.P.Notes on a Form of Black Diamond from the Premier MineGeological Society of South Africa Transactions, Vol. 16, PP. 156-161. ALSO: CHEM. abstract., Vol. 8, P. 3168.South Africa, Kimberley AreaMorphology, Mineralogy
DS2002-0802
2002
McDonald, G.D.Kamber, B.S., Ewart, A., Collerson, K.D., Bruce, M.C., McDonald, G.D.Fluid mobile trace element constraints on the role of slab melting and implications for Archean crustal growth models.Contributions to Mineralogy and Petrology, Vol. 144, 1, Oct. pp. 38-56.CrustSubduction, Tectonics
DS1994-1145
1994
McDonald, I.McDonald, I., Bizzi, L.A., De Wit, M..The geochemistry (platinum group elements (PGE)) in kimberlites and constraints of the nature platinum group elements (PGE) insubcratonic lithospheric mantle.International Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 73-75.Brazil, South AfricaKimberlites, Geochemistry
DS1994-1146
1994
McDonald, I.McDonald, I., De Wit, M.J., Bizzi, L.A.The geochemistry of the Platinum group elements in kimberlites and the nature platinum group elements (PGE) in subcratonic mantle.Mineralogical Magazine, Vol. 58A, pp. 581-582. AbstractMantleGeochemistry, Platinum in kimberlites
DS1994-1147
1994
McDonald, I.McDonald, I., Hart, R.J., Tredoux, M.Determination of platinum group elements (PGE)'sin South African kimberlites by nickel sulfide fine assay and neutron activation analysis.Analytical Chim., Vol. 289, No. 2, Apr. 29, pp. 237-249.South AfricaKimberlites, PlatinuM.
DS1995-0155
1995
McDonald, I.Bizzi, L.A., Dewit, M.J., Smith, C.B., McDonald, I., et al.Heterogeneous enriched mantle materials and dupal type magmatism along southwest margin of Sao Francisco craton.Journal of Geodynamics, Vol. 20, No. 4, Dec. pp. 469-491.BrazilMagmatism, petrology, Craton -Sao Francisco
DS1995-1208
1995
McDonald, I.McDonald, I., De Wit, M.J., Smith, C.B., Bizzi, L.A. etc.The geochemistry of platinum group elements in Brazilian and Southern african kimberlites.Geochimica et Cosmochimica Acta, Vol. 59, No. 14, July pp. 2883-2904.Brazil, South Africa, BotswanaGeochemistry -platinum group elements (PGE), Kimberlites
DS1996-0923
1996
McDonald, I.McDonald, I.Determination of noble metals in sulphide inclusions from diamonds using inductively coupled plasma mass spectrometryAnalytica et Chimica Acta, Vol. 333, No. 1-2, pp. 41-49.GlobalDiamonds -Sulfide inclusions, Mass spectrometry
DS1999-0460
1999
McDonald, I.McDonald, I., Ohenstetter, D.Palladium oxides in ultramafic complexes near Lavatrafo, WesternAndriemena.Mineralogical Magazine, Vol. 63, No. 3, June, pp. 345-52.MadagascarUltramafic rocks
DS2001-0754
2001
McDonald, I.McDonald, I., Harris, J.W., Viljoen, K.S.Can the nickel copper platinum group elements (PGE) signatures of sulphide inclusions in diamond help to constrain diamond formation processes?Institute of Mining and Metallurgy (IMM) Transactions. Durham Meeting absts., Vol. 110, p. B46. abstractGlobalDiamond - inclusions, genesis
DS200712-0669
2007
McDonald, I.Maier, W.D., McDonald, I., Peltonen, P., Barnes, S-J., Gurney, J., Hatton, C.Platinum group elements in mantle xenoliths from the Kaapvaal Craton.Plates, Plumes, and Paradigms, 1p. abstract p. A614.Africa, South Africa, Botswana, LesothoKimberley, Jagersfontein, Lethlakane, Finsch, Venetia
DS200712-0706
2006
McDonald, I.McDonald, I., Viljoen, K.S.Platinum group element geochemistry of mantle eclogites: a reconnaissance study of xenoliths from the Orapa kimberlite, Botswana.Transactions of Institute of Mining and Metallurgy, Vol. 115, no. 3, Sept. pp. B 81-93.Africa, BotswanaDeposit - Orapa, PGE, eclogites
DS200912-0151
2009
McDonald, I.Dare, S.A.S., Pearce, J.A., McDonald, I.,Styles, M.T.Tectonic discrimination of peridotites using fO2 Cr# and Ga Ti Fe111 systematics in chrome spinel.Chemical Geology, Vol. 261, 3-4, April 30, pp. 199-216.TechnologyMineral chemistry database
DS201212-0364
2012
McDonald, I.Koeberl, C., Claeys, P., Hecht, L., McDonald, I.Geochemistry of impactites.Elements, Vol. 8, 1, Feb. pp. 37-42.TechnologyPGM, isotopes
DS201212-0430
2012
McDonald, I.Maier, W.D., Peltonen, P., McDonald, I., Barnes, S.J., Barnes, S-J., Hatton, C., Viljoen, F.The concentration of platinum group elements and gold in southern African and Karelian kimberlite hosted mantle xenoliths: implications for the noble metal content of the Earth's mantle.Chemical Geology, Vol. 302-303, pp. 119-135.Africa, southern AfricaKimberlite - PGM
DS201707-1349
2017
McDonald, I.McDonald, I., Hughes, H.S.R., Butler, I.B., Harris, J.W., Muir, D.Homogenization of sulphide inclusions within diamonds: a new approach to diamond inclusion geochemistry.Geochimica et Cosmochimica Acta, available in press 23p.Africa, Botswanadeposit - Orapa

Abstract: Base metal sulphide (BMS) inclusions in diamonds provide a unique insight into the chalcophile and highly siderophile element composition of the mantle. Entombed within their diamond hosts, these provide a more robust (closed system) sample, from which to determine the trace element, Re-Os and S-isotopic compositions of the mantle than mantle xenoliths or orogenic peridotites, as they are shielded from alteration during ascent to the Earth’s crust and subsequent surface weathering. However, at temperatures below 1100 °C some BMS inclusions undergo subsolidus re-equilibration from an original monosulphide solid solution (Mss) and this causes fractionation of the major and trace elements within the inclusions. Thus to study the subjects noted above, current techniques require the entire BMS inclusion to be extracted for analyses. Unfortunately, ‘flaking’ of inclusions during break-out is a frequent occurrence and hence the risk of accidentally under-sampling a portion of the BMS inclusion is inherent in current practices. This loss may have significant implications for Re-Os isotope analyses where incomplete sampling of a Re-rich phase, such as chalcopyrite that typically occurs at the outer margins of BMS inclusions, may induce significant bias in the Re-Os and 187Os/188Os measurements and resulting model and isochron ages. We have developed a method for the homogenisation of BMS inclusions in diamond prior to their break-out from the host stone. Diamonds are heated to 1100 °C and then quenched to chemically homogenise any sulphide inclusions for both major and trace elements. Using X-ray Computed Microtomography (µCT) we determine the shape and spatial setting of multiple inclusions within a host stone and crucially show that the volume of a BMS inclusion is the same both before and after homogenisation. We show that the homogenisation process significantly reduces the inherent variability of in situ analysis when compared with unhomogenised BMS, thereby widening the scope for multiple methods for quantitative analysis, even on ‘flakes’ of single BMS inclusions. Finally we show that the trace elements present in peridotite (P-type) and eclogitic (E-type) BMS are distinct, with P-type diamonds having systematically higher total platinum-group element (particularly Os, Ir, Ru) and Te and As concentrations. These distinctions suggest that the PGE and semi-metal budgets of mantle-derived partial melts will be significantly dependent upon the type(s) and proportions of sulphides present in the mantle source.
DS201709-2030
2017
McDonald, I.McDonald, I., Hughes, H.S.R., Butler, I.B., Harris, J.W., Muir, D.Homogenisation of sulphide inclusions within diamonds: a new approach to diamond inclusion geochemistry.Geochimica et Cosmochimica Acta, in press available, 23p.Technologydiamond inclusions

Abstract: Base metal sulphide (BMS) inclusions in diamonds provide a unique insight into the chalcophile and highly siderophile element composition of the mantle. Entombed within their diamond hosts, these provide a more robust (closed system) sample, from which to determine the trace element, Re-Os and S-isotopic compositions of the mantle than mantle xenoliths or orogenic peridotites, as they are shielded from alteration during ascent to the Earth’s crust and subsequent surface weathering. However, at temperatures below 1100 °C some BMS inclusions undergo subsolidus re-equilibration from an original monosulphide solid solution (Mss) and this causes fractionation of the major and trace elements within the inclusions. Thus to study the subjects noted above, current techniques require the entire BMS inclusion to be extracted for analyses. Unfortunately, ‘flaking’ of inclusions during break-out is a frequent occurrence and hence the risk of accidentally under-sampling a portion of the BMS inclusion is inherent in current practices. This loss may have significant implications for Re-Os isotope analyses where incomplete sampling of a Re-rich phase, such as chalcopyrite that typically occurs at the outer margins of BMS inclusions, may induce significant bias in the Re-Os and 187Os/188Os measurements and resulting model and isochron ages. We have developed a method for the homogenisation of BMS inclusions in diamond prior to their break-out from the host stone. Diamonds are heated to 1100 °C and then quenched to chemically homogenise any sulphide inclusions for both major and trace elements. Using X-ray Computed Microtomography (µCT) we determine the shape and spatial setting of multiple inclusions within a host stone and crucially show that the volume of a BMS inclusion is the same both before and after homogenisation. We show that the homogenisation process significantly reduces the inherent variability of in situ analysis when compared with unhomogenised BMS, thereby widening the scope for multiple methods for quantitative analysis, even on ‘flakes’ of single BMS inclusions. Finally we show that the trace elements present in peridotite (P-type) and eclogitic (E-type) BMS are distinct, with P-type diamonds having systematically higher total platinum-group element (particularly Os, Ir, Ru) and Te and As concentrations. These distinctions suggest that the PGE and semi-metal budgets of mantle-derived partial melts will be significantly dependent upon the type(s) and proportions of sulphides present in the mantle source.
DS201710-2246
2017
McDonald, I.McDonald, I., Hughes, H.S.R., Butler, I.B., Harris, J.W., Muir, D.Homogenization of sulphide inclusions within diamonds: a new approach to diamond inclusion geochemistry.Geochimica et Cosmochimica Acta, Vol. 216, pp. 335-357.Technologydiamond inclusions - microtomography

Abstract: Base metal sulphide (BMS) inclusions in diamonds provide a unique insight into the chalcophile and highly siderophile element composition of the mantle. Entombed within their diamond hosts, these provide a more robust (closed system) sample, from which to determine the trace element, Re-Os and S-isotopic compositions of the mantle than mantle xenoliths or orogenic peridotites, as they are shielded from alteration during ascent to the Earth’s crust and subsequent surface weathering. However, at temperatures below 1100 °C some BMS inclusions undergo subsolidus re-equilibration from an original monosulphide solid solution (Mss) and this causes fractionation of the major and trace elements within the inclusions. Thus to study the subjects noted above, current techniques require the entire BMS inclusion to be extracted for analyses. Unfortunately, ‘flaking’ of inclusions during break-out is a frequent occurrence and hence the risk of accidentally under-sampling a portion of the BMS inclusion is inherent in current practices. This loss may have significant implications for Re-Os isotope analyses where incomplete sampling of a Re-rich phase, such as chalcopyrite that typically occurs at the outer margins of BMS inclusions, may induce significant bias in the Re-Os and 187Os/188Os measurements and resulting model and isochron ages. We have developed a method for the homogenisation of BMS inclusions in diamond prior to their break-out from the host stone. Diamonds are heated to 1100 °C and then quenched to chemically homogenise any sulphide inclusions for both major and trace elements. Using X-ray Computed Microtomography (µCT) we determine the shape and spatial setting of multiple inclusions within a host stone and crucially show that the volume of a BMS inclusion is the same both before and after homogenisation. We show that the homogenisation process significantly reduces the inherent variability of in situ analysis when compared with unhomogenised BMS, thereby widening the scope for multiple methods for quantitative analysis, even on ‘flakes’ of single BMS inclusions. Finally we show that the trace elements present in peridotite (P-type) and eclogitic (E-type) BMS are distinct, with P-type diamonds having systematically higher total platinum-group element (particularly Os, Ir, Ru) and Te and As concentrations. These distinctions suggest that the PGE and semi-metal budgets of mantle-derived partial melts will be significantly dependent upon the type(s) and proportions of sulphides present in the mantle source.
DS202001-0016
2019
McDonald, I.Holwell, D.A., Fiorentini, M., McDonald, I., Lu, Y., Giuliani, A., Smith, D.J., Keith, M., Locmelis, M.A metasomatized lithospheric mantle control on the metallogenic signature of post-subduction magmatism. ( Not specific to diamonds)Nature Communications, doi.org/10.1038/s41467-019-11065-4 pdf 10p.Mantlesubduction

Abstract: Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems. We propose that a trans-lithospheric continuum exists whereby post-subduction magmas transporting metal-rich sulfide cargoes play a fundamental role in fluxing metals into the crust from metasomatised lithospheric mantle. Therefore, ore deposits are not merely associated with isolated zones where serendipitous happenstance has produced mineralisation. Rather, they are depositional points along the mantle-to-upper crust pathway of magmas and hydrothermal fluids, synthesising the concentrated metallogenic budget available.
DS1997-0917
1997
McDonald, J.Pokhilenko, N.P., McDonald, J., Melnik, U., McCorquodaleIndicator minerals of CL-25 kimberlite pipe Slave Craton, NorthwestTerritories, Canada.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 550-558.Northwest TerritoriesGeochemistry, Deposit - CL-25
DS2002-1602
2002
McDonald, J.Tocher, S.N., McDonald, J.Geological report for Alberta diamond property Grande Cache areaMineral Assesment Files, Alberta Geological Survey, www.ags.gov.ab.ca, MIN 0106AlbertaAssessment - Grande Cache area
DS1995-1506
1995
McDonald, J.A.Pokhilenko, N.P., McDonald, J.A., Melnyk, W., McCorquodaleIndicator minerals of CL 25 kimberlite pipe, Slave Craton, northwest TerritoriesProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 444-445.Northwest TerritoriesGeochemistry -indicator minerals, Deposit -CL-25 pipe
DS1998-0977
1998
McDonald, J.A.McDonald, J.A., Pokhilenko, N., Melnyk, W., Hall, A.Camsell Lake kimberlites, Slave Province, northwest TerritoriesGeological Society of America (GSA) Annual Meeting, abstract. only, p.A245.Northwest TerritoriesExploration - history outline, Deposit - Camsell Lake, Snap Lake, dike
DS1998-1174
1998
McDonald, J.A.Pokhilenko, N.P., McDonald, J.A., Melnyk, Hall, ShimizuKimberlites of Camsell Lake field and some features of construction and composition of lithosphere roots...7th. Kimberlite Conference abstract, pp. 699-701.Northwest TerritoriesCraton - Slave, Deposit - Camsell Lake
DS1998-1341
1998
McDonald, J.A.Shimizu, N., Pokhilenko, N.P., McDonald, J.A.Geochemical characteristics of the Slave Craton lithosphere: a view heavy mineral concentrate garnets7th International Kimberlite Conference Abstract, pp. 805-6.Northwest TerritoriesGeochemistry, Peridotite diamonds
DS2002-1032
2002
McDonald, J.A.McDonald, J.A., Pokhilenko, N., Melnyk, W., Hall, A.Camsell Lake kimberlites, Slave Province, Northwest TerritoriesCanadian Institute of Mining and Metallurgy, Vol. 53, Industrial Minerals of Canada, pp. 361-2.Northwest TerritoriesHistory - exploration
DS2003-1090
2003
McDonald, J.A.Pokhilenko, N.P., Agashev, A.M., McDonald, J.A., Sobolev, N.V., MityukhinKimberlites of the Nakyn field, Siberia and the Snap Lake King Lake dyke system8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractNorthwest TerritoriesDeposit - Snap Lake, King Lake
DS2003-1091
2003
McDonald, J.A.Pokhilenko, N.P., Agashev, A.M., McDonald, J.A., Vavilov, M.A., Clark, D.B..Kimberlites and carbonatites of the Snap Lake King Lake dyke system: structural8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractNorthwest TerritoriesDeposit - Snap Lake, King Lake
DS2003-1093
2003
McDonald, J.A.Pokhilenko, N.P., McDonald, J.A., Sobolev, N.V., Reutsky, V.N., Hall, A.E.Crystalline inclusions and C isotope composition of diamonds from the Snap lake/King8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractNorthwest TerritoriesDiamonds - geochronology, Deposit - Snap Lake
DS2003-1094
2003
McDonald, J.A.Pokhilenko, N.P., McDonald, J.A., Turner, R.C.Snap Lake kimberlite dyke system - history and methods of a new type of largeGeological Association of Canada Annual Meeting, Abstract onlyNorthwest TerritoriesTechniques
DS200412-1561
2003
McDonald, J.A.Pokhilenko, N.P., Agashev, A.M., McDonald, J.A., Sobolev, N.V., Mityukhin, S.I., Vavilov, M.A., Yanygin, Y.T.Kimberlites of the Nakyn field, Siberia and the Snap Lake King Lake dyke system, Slave Craton, Canada: a new variety of kimberli8 IKC Program, Session 7, POSTER abstractCanada, Northwest TerritoriesKimberlite petrogenesis Deposit - Snap Lake, King Lake
DS200412-1562
2003
McDonald, J.A.Pokhilenko, N.P., Agashev, A.M., McDonald, J.A., Vavilov, M.A., Clark, D.B., Wright, K.J.Kimberlites and carbonatites of the Snap Lake King Lake dyke system: structural setting, petrochemistry and petrology of a uniqu8 IKC Program, Session 7, POSTER abstractCanada, Northwest TerritoriesKimberlite petrogenesis Deposit - Snap Lake, King Lake
DS200412-1564
2003
McDonald, J.A.Pokhilenko, N.P., McDonald, J.A., Sobolev, N.V., Reutsky, V.N., Hall, A.E., Logvinova, A.M., Reimers, L.F.Crystalline inclusions and C isotope composition of diamonds from the Snap lake/King Lake kimberlite dyke system: evidence for a8 IKC Program, Session 3, AbstractCanada, Northwest TerritoriesDiamonds - geochronology Deposit - Snap Lake
DS200412-1565
2003
McDonald, J.A.Pokhilenko, N.P., McDonald, J.A., Turner, R.C.Snap Lake kimberlite dyke system - history and methods of a new type of large primary diamond deposit discovery.Geological Association of Canada Annual Meeting, Abstract onlyCanada, Northwest TerritoriesTechniques
DS200812-0004
2008
McDonald, J.A.Agashev, A.M., Pokhilenko, N.P., Takazawa, E., McDonald, J.A., Vavilov, M.A., Watanabe, T., Sobolev, N.V.Primary melting sequence of a deep ( >250 km) lithospheric mantle as recorded in the geochemistry of kimberlite carbonatite assemblages, Snap Lake dyke system, Canada.Chemical Geology, Vol. 255, 3-4, pp. 317-328.Canada, Northwest TerritoriesDeposit - Snap Lake
DS201212-0562
2012
McDonald, J.A.Pokhilenko, N.P., Afanasev, V.P., McDonald, J.A., Vavilov, M.A., Kulgin, S.S., Pokhilenko, L.N., Golovin, A.V., Agashev, A.M.Kimberlite indicator minerals in terrigene sediments of lower part of Mackenzie River Basin, NWT, Canada: evidence of new craton with thick lithosphere.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractCanada, Northwest TerritoriesGeochemistry - KIMS
DS1920-0343
1927
Mcdonald, J.G.Mcdonald, J.G.Rhodes, a LifeLondon: P. Allan., 403P.South AfricaBiography, Kimberley
DS1995-1256
1995
McDonald, L.Miller, J.D.Jr., McDonald, L., DeShane, G., Balaban, N.Field trip guidebook for the geology and ore deposits of the Midcontinent rift in the Lake Superior region #1Minnesota Geological Survey, University of Minnesota, Guidebook No. 20, 216p.OntarioMidcontent Rift
DS1996-0924
1996
McDonald, R.McDonald, R.Mergers and acquisitions - a profitable way to grow?Australian Institute of Mining and Metallurgy (AusIMM) Bulletin, No. 8, Dec. pp. 45-46GlobalEconomics, Mergers, acqusitions, financing
DS1993-0997
1993
McDonald, R.J.McDonald, R.J.Rates of return and the cost of equity capital to the mining industry: an Australian perspectiveAusIMM, Centennary Conference Volume, pp. 239-250AustraliaEconomics, Mining finance
DS2000-0647
2000
McDononough, M.R.McNicoll, V.J., Theriault, R.J., McDononough, M.R.Taltson basement gneissic rocks: uranium-lead (U-Pb) and neodymium isotopic constraints on the basement to the Paleoproterozoic..Canadian Journal of Earth Sciences, Vol.37, No.11, Nov.pp.1575-96.AlbertaTectonics - Paleoproterozoic Taltson magmatic zone, Geochronology
DS2002-0111
2002
McDononough, W.F.Barth, M.G., Rudnick, R.L., Carlson, R.W., Horn, J., McDononough, W.F.Re Os and U Pb geochronological constraints on the eclogite tonalite connection in the Archean Man Shield, West Africa.Precambrian Research, Vol. 118, 3-4, pp. 267-83.West Africa, Liberia, Sierra LeoneGeochronology, Eclogite
DS2002-0112
2002
McDononough, W.F.Barth, M.G., Rudnick, R.L., Horn, J., McDononough, W.F., Spicuzza, M.J.Geochemistry of xenolithic eclogites from West Africa: part 2. origins of the high MgO eclogites.Geochimica et Cosmochimica Acta, Vol. 66, 24, pp. 4325-45.West Africa, Liberia, Sierra LeoneEclogites
DS2002-1051
2002
McDononough, W.F.Michael, P.J., McDononough, W.F., Nielsen, R. Cornell.Depleted melt inclusions in MORB plagioclase: messages from the mantle or mirages from the magma chamber.Chemical Geology, Vol.183, 1-4, pp.43-61.MantleMagma, mid ocean rid basalts, Geochemistry
DS200612-0890
2006
McDononough, W.F.McDononough, W.F., Arevalo, R.D.Crust mantle and core mantle recycling.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 30. abstract only.MantleSubduction
DS200912-0010
2009
McDononough, W.F.Arevalo, R., McDononough, W.F., Luong, M.The K/U ratio of the silicate Earth: insights into mantle composition, structure and thermal evolution.Earth and Planetary Science Letters, Vol. 278 3-4, pp. 361-369.MantleGeothermometry
DS2002-0497
2002
McDonoughGao, S., Rudnick, R.L., Carlson, R.W., McDonough, LiuRe-Os evidence for replacement of ancient mantle lithosphere beneath the North Chin a Craton.Earth and Planetary Science Letters, Vol.198,3-4,pp. 307-22., Vol.198,3-4,pp. 307-22.ChinaGeochronology, Craton - North China
DS2002-0498
2002
McDonoughGao, S., Rudnick, R.L., Carlson, R.W., McDonough, LiuRe-Os evidence for replacement of ancient mantle lithosphere beneath the North Chin a Craton.Earth and Planetary Science Letters, Vol.198,3-4,pp. 307-22., Vol.198,3-4,pp. 307-22.ChinaGeochronology, Craton - North China
DS200712-1107
2007
McDonoughVan Acken, D., Becker, H., Wombacher, Walker, McDonough, Ash, PiccoliFractionated HSE in suboceanic mantle: assessing the influence of refertilization processes on upper mantle peridotites.Plates, Plumes, and Paradigms, 1p. abstract p. A1051.Europe, SwitzerlandWebsterite
DS201412-0360
2014
McDonough, B.Hirose, K., McDonough, B., McNamara, A.Chemical composition of Earth's mantle.Goldschmidt Conference 2014, 1p. AbstractMantleMineral chemistry
DS1993-0998
1993
McDonough, M.R.McDonough, M.R., et al.Geology, Mercredi Lake Alberta-Northwest TerritoriesGeological Survey of Canada, Open file, No. 2629, 1 mapNorthwest TerritoriesMercredi Lake, Open File -ad
DS1997-0754
1997
McDonough, M.R.McDonough, M.R., McNicoll, V.J.uranium-lead (U-Pb) age constraints on the timing of deposition of the Wagh Lake and Burntwood Athabasca Groups, Taltson zoneGeological Society of Canada (GSC) Paper, No. 1997-F, p. 101-111.AlbertaGeochronology, Southern Taltson magmatic zone
DS2000-0646
2000
McDonough, M.R.McDonough, M.R., McNicoll, V.J., Schetselaar, GroverGeochronological and kinematic constraints on crustal shortening and escape in a two sided oblique slip...Canadian Journal of Earth Sciences, Vol.37, no11, Nov.pp.1549-73.Alberta, northeasternTectonics - Paleoproterozoic Taltson magmatic zone, Geochronology
DS1998-1263
1998
McDonough, W.Rudnick, R.L., Barth, M., McDonough, W., Horn, I.Rutiles in ecologites: a missing earth reservoir found?Geological Society of America (GSA) Annual Meeting, abstract. only, p.A207.Africa, SiberiaSubduction, Craton, xenoliths, Kimberlites
DS201012-0483
2010
McDonough, W.McDonough, W.Compositional models of the Earth, mantle and core revisited.Goldschmidt 2010 abstracts, AbstractMantleGeochemistry
DS1985-0430
1985
Mcdonough, W.F.Mcdonough, W.F., Mcculloch, M.T.Geochemical and Isotopic Systematics of Spinel Lherzolites from Southeast Australia.Eos, Vol. 66, No. 46, NOVEMBER 12, P. 1110. (abstract.).Australia, Southeast Australia, VictoriaGeochemistry
DS1985-0431
1985
Mcdonough, W.F.Mcdonough, W.F., Mcculloch, M.T., Sun, S.S.Isotopic and Geochemical Systematics in Tertiary Recent Basalts from Southeastern Australia and Implications for the Evolution of the Subcontinental Lithosphere.Geochimica et Cosmochimica ACTA., Vol. 49, No. 10, PP. 2051-2067.Australia, Southeast AustraliaPetrology, Basalt
DS1986-0549
1986
McDonough, W.F.McDonough, W.F., McCulloch, M.T.Chemical and isotopic evolution of the southeast AustraliansubcontinentallithosphereProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 288-290AustraliaGeochemistry
DS1987-0455
1987
McDonough, W.F.McDonough, W.F., McCulloch, M.T.Growth and evolution of the subcrustal lithosphere: oceanic versuscontinentalTerra Cognita, Conference abstracts Oceanic and Continental Lithosphere:, Vol. 7, No. 4, Autumn, abstract only p. 619AustraliaBlank
DS1987-0456
1987
McDonough, W.F.McDonough, W.F., McCulloch, M.T.The southeast Australian lithospheric mantle: isotopic and geochemical constraints on its growth and evolutionEarth and Planetary Science Letters, Vol. 86, pp. 327-340AustraliaBlank
DS1989-0714
1989
McDonough, W.F.Jochum, K.P., McDonough, W.F., Palme, H., Spettel, B.Compositional constraints on the continental lithospheric mantle from trace elements in spinel peridotite xenolithsNature, Vol. 340, No. 6234, August 17, pp. 548-550GlobalMantle, Xenoliths
DS1989-0983
1989
McDonough, W.F.McDonough, W.F., Frey, F.A.Rare earth elements in upper mantle rocks. Massiveperidotites, ultramafic xenoliths, megacrysts, minerals in xenoliths and diamond inclusionsReviews in Mineralogy: Geochemistry and mineralogy of Rare earth, Vol. 21, pp. 99-139Globalrare earth elements (REE) Mantle, Diamond inclusions
DS1990-1008
1990
McDonough, W.F.McDonough, W.F.Constraints on the composition of the continental lithospheric mantle #2Earth and Planetary Science Letters, Vol. 101, pp. 1-18AustraliaMantle, Geochemistry
DS1990-1009
1990
McDonough, W.F.McDonough, W.F.Chemical and isotopic systematics of continental mantle #1Eos, Vol. 71, No. 43, October 23, p. 1670 AbstractGlobalMantle, Geochemistry
DS1990-1010
1990
McDonough, W.F.McDonough, W.F., Jochum, K.P.Constraints on the composition of the continental lithospheric mantle #1Geological Society of Australia Abstracts, No. 25, No. A12.11 pp. 245. AbstractGlobalXenoliths, Mantle
DS1991-1101
1991
McDonough, W.F.McDonough, W.F.Partial melting of subducted oceanic crust and isolation of its residual eclogitic lithologyPhil. Transactions R. Soc. London, Sect. A., Vol. 335, No. 1638, May 15, pp. 407-418GlobalMantle, Eclogite
DS1991-1102
1991
McDonough, W.F.McDonough, W.F.Chemical and isotopic systematics of continental mantle #2Proceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 270-272GlobalPeridotite xenolith, spinel, garnet, Geochemistry
DS1991-1470
1991
McDonough, W.F.Rudnick, R.L., McDonough, W.F., Chappell, B.W.Cratonic and oceanic lithospheric mantle beneath northern TanzaniaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 344-346TanzaniaCraton, peridotite xenoliths, Lashaine, Olmani
DS1992-1029
1992
McDonough, W.F.McDonough, W.F.Composition of the primitive mantle, depleted mantle and other mantlereservoirsProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 1, abstract p. 175MantleMantle reservoirs, Geochemistry
DS1993-0999
1993
McDonough, W.F.McDonough, W.F., Ireland, T.R.Intraplate origin of komatiites inferred from trace elements in glassinclusionsNature, Vol. 365, No. 6445, September 30, pp. 432-434GlobalKomatiites, Genesis
DS1993-1347
1993
McDonough, W.F.Rudnick, R.L., McDonough, W.F., Chappell, B.W.Carbonatite metasomatism in the northern Tanzanian mantle: petrographic and geochemical characteristics.Earth and Planetary Science Letters, Vol. 114, pp. 463-475.TanzaniaCarbonatite, Geochemistry
DS1994-1148
1994
McDonough, W.F.McDonough, W.F.Chemical and isotopic systematics of continental lithospheric mantleProceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 478-485.MantleGeochronology
DS1994-1494
1994
McDonough, W.F.Rudnick, R.L., McDonough, W.F., Orpin, A.Northern Tanzania peridotite xenoliths: a comparison with Kaapvaal peridotites and inference of metasomatic reactions.Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 336-353.TanzaniaXenoliths, Peridotites
DS1995-1209
1995
McDonough, W.F.McDonough, W.F., Sun, S.S.The composition of the earthChemical Geology, Vol. 120, No. 3-4, March 1, pp. 223-253.Mantle, EarthGeophysics -seismics, Melt relationships
DS1998-0978
1998
McDonough, W.F.McDonough, W.F., Rudnick, R.L.Mineralogy and composition of the Upper MantleReviews in Mineralogy, Vol. 37, pp. 139-64.MantleMineralogy, Geochemistry
DS1998-1266
1998
McDonough, W.F.Rudnick, R.L., McDonough, W.F., O'Connell, R.J.Thermal structure, thickness and composition of continental lithosphereChemical Geology, Vol. 145, No. 3-4, Apr. 15, pp. 395-412.MantleTectonics
DS1999-0461
1999
McDonough, W.F.McDonough, W.F.Earth's coreEncyclopedia Geochemistry, Marshall and Fairbridge, pp. 151-5.GlobalDefinition
DS2000-0560
2000
McDonough, W.F.Lee, C.T., Rudnick, R.L., McDonough, W.F., Horn, I.Petrologic and geochemical investigation of carbonates in peridotite xenoliths from northeastern Tanzania.Contributions to Mineralogy and Petrology, Vol. 139, No. 4, pp. 470-84.TanzaniaGeochemistry, petrology, Peridotite xenoliths
DS2001-0089
2001
McDonough, W.F.Barth, M.G., Rudnick, R.L., Hor, I., McDonough, W.F.Geochemistry of xenolithic eclogites from West Africa: 1. a link between low MgO eclogites and archean crustGeochimica et Cosmochimica Acta, Vol. 65, No. 9, pp. 1499-1527.Sierra LeoneWhole rock compositions, Deposit - Koidu
DS2003-1195
2003
McDonough, W.F.Rudnick, R.L., McDonough, W.F.,Tomascak, P.B., Zack, T.Lithium isotopic composition of eclogites - implications for subduction zone processes8 Ikc Www.venuewest.com/8ikc/program.htm, Session 4, AbstractSierra LeoneMantle geochemistry, Deposit - Koidu
DS2003-1539
2003
McDonough, W.F.Zack, T., Tomascak, P.B., Rudnick, R.L., Dalpe, C., McDonough, W.F.Extremely light Li in orogenic eclogites: the role of isotope fractionation duringEarth and Planetary Science Letters, Vol. 208, 3-4, pp. 279-90.MantleEclogites
DS2003-1540
2003
McDonough, W.F.Zack, T., Tomascek, P.R., Rudnick, R.L., Dalpe, C., McDonough, W.F.Extremely light Li in orogenic eclogites: the role of isotope fractionation duringEarth and Planetary Science Letters, Vol. 208, 3-4, March 30, pp.279-90.SwitzerlandSubduction - not specific to diamonds
DS200412-1700
2004
McDonough, W.F.Rudnick, R.L., Gao, S., Ling, W-I., Liu, Y-S., McDonough, W.F.Petrology and geochemistry of spinel peridotite xenoliths from Hannuoba and Qixia, North Chin a Craton.Lithos, Vol. 77, 1-4, Sept. pp. 609-637.ChinaArchean craton, geochemistry, major, trace, thermometry
DS200412-1702
2003
McDonough, W.F.Rudnick, R.L., McDonough, W.F.,Tomascak, P.B., Zack, T.Lithium isotopic composition of eclogites - implications for subduction zone processes.8 IKC Program, Session 4, AbstractAfrica, Sierra LeoneMantle geochemistry Deposit - Koidu
DS200412-2194
2003
McDonough, W.F.Zack, T., Tomascak, P.B., Rudnick, R.L., Dalpe, C., McDonough, W.F.Extremely light Li in orogenic eclogites: the role of isotope fractionation during dehydration in subducted oceanic crust.Earth and Planetary Science Letters, Vol. 208, 3-4, pp. 279-90.MantleEclogite
DS200412-2195
2003
McDonough, W.F.Zack, T., Tomascek, P.R., Rudnick, R.L., Dalpe, C., McDonough, W.F.Extremely light Li in orogenic eclogites: the role of isotope fractionation during dehydration in subducted oceanic crust.Earth and Planetary Science Letters, Vol. 208, 3-4, March 30, pp.279-90.Europe, SwitzerlandSubduction - not specific to diamonds
DS200512-0517
2005
McDonough, W.F.Keshav, S., Corgne, A., Gudfinnasson, G.H., Bizimis, M., McDonough, W.F., Fei, Y.Kimberlite petrogenesis: insights from clinopyroxene melt partitioning experiments at 6 GPa in the CaO MgO Al2O3 SiO2 CO2 system.Geochimica et Cosmochimica Acta, Vol. 69, 11, June 1, pp. 2829-2845.Africa, South AfricaGroup I, modeling
DS200512-1078
2004
McDonough, W.F.Teng, F.Z., McDonough, W.F., Rudnick, R.L., Dalpe, C., Tomascak, P.B., Chappell, B.W., Gao, S.Lithium isotopic composition and concentration of the upper continental crust.Geochimica et Cosmochimica Acta, Vol. 68, 20, pp. 4167-4178.MantleGeochemistry, geochronology
DS200612-0279
2006
McDonough, W.F.Corgne, A., Keshav, S., Fei, Y., McDonough, W.F.How much potassium is in the Earth's core? New insights from partitioning experiments.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 114. abstract only.MantleMineral chemistry
DS200612-0842
2006
McDonough, W.F.Lundstrom, C.C., Sutton, A.L., McDonough, W.F., Ash, R.Trace element partitioning between type B CAI melts and melilite and spinel: implications for trace element distribution during CAI formation.Geochimica et Cosmochimica Acta, Vol. 70, 13, pp. 3421-3435.TechnologyCalcium aluminum rich inclusions, melilite melting
DS200712-0039
2007
McDonough, W.F.Aulbach, S., Rudnick, R.L., McDonough, W.F.Li Sr Nd isotope signatures of the plume and cratonic lithospheric mantle beneath the margin of the rifted Tanzanian craton (Labait).Contributions to Mineralogy and Petrology, Vol. 155, 1, pp. 79-92.Africa, TanzaniaGeochronology
DS200712-0201
2007
McDonough, W.F.Corgne, A., Keshav, S., Fei, Y., McDonough, W.F.How much potassium is in the Earth's core? New insights from partitioning experiments.Earth and Planetary Science Letters, Vol. 256, 3-4, pp. 567-576.MantleGeochemistry
DS200712-0403
2007
McDonough, W.F.Halama, R., McDonough, W.F., Rudnick, R.L., Keller, J., Klaudius, J.The Li isotopic composition of Oldoinyo Lengai: nature of the mantle sources and lack of isotopic fractionation during carbonatitic petrogenesis.Earth and Planetary Science Letters, Vol. 254, 1-2, Feb. 15, pp. 77-89.Africa, TanzaniaGeochronology, carbonatite
DS200812-0061
2008
McDonough, W.F.Aulbach, S., Rudnick, R.L., McDonough, W.F.Lithospheric mantle sources within the East African Rift, Tanzania.Goldschmidt Conference 2008, Abstract p.A37.Africa, TanzaniaLahait Craton, carbonatites
DS200812-0442
2008
McDonough, W.F.Halama, R., McDonough, W.F., Rudnick, R.L., Bell, K.Tracking the lithium isotopic evolution of the mantle using carbonatites.Earth and Planetary Science Letters, Vol. 265, 3-4, Jan. 30, pp. 726-742.MantleCarbonatite
DS200812-0731
2008
McDonough, W.F.McDonough, W.F.Earth Science: deducing a reducing mantle.Nature, Vol. 455, 7215, Oct. 16, pp. 881-882.MantleReduction
DS200812-0732
2008
McDonough, W.F.McDonough, W.F., Arevalo, R.J.Mantle convection and K/U.Goldschmidt Conference 2008, Abstract p.A613.MantleConvection
DS200812-1162
2008
McDonough, W.F.Teng, F-Z., Rudnick, R.L., McDonough, W.F., Gao, S., Tomascal, P.B., Liu, Y.Lithium isotopic composition and concentration of the deep continental crust.Chemical Geology, Vol. 255, 1-2, Sept. 30, pp. 47-59.MantleGeochronology
DS200912-0153
2009
McDonough, W.F.Dasgupta, R., Hirschmann, M.M., McDonough, W.F., Spiegelman, M., Withers, A.C.Trace element partitioning between garnet lherzolite and carbonatite at 6.6 and 8.6 GPa with application to the geochemistry of the mantle and mantle derived meltsChemical Geology, Vol. 262, 1-2, May 15, pp. 57-77.MantleMelting
DS200912-0624
2009
McDonough, W.F.Revalo, R.Jr., McDonough, W.F., Luong, M.The K/U ratio of the silicate Earth: insights into mantle composition, structure and thermal evolution.Earth and Planetary Interiors, Vol. 278, 3-4, pp. 361-369.MantleGeothermometry
DS201112-0078
2011
McDonough, W.F.Bellucci, J.J., McDonough, W.F., Rudnick, R.L.Thermal history and origin of the Tanzanian Craton from Pb isotope thermochronology of feldspars from lower crustal xenoliths.Earth and Planetary Science Letters, Vol. 301, 3-4, pp. 493-501.Africa, TanzaniaGeothermometry
DS201112-0133
2011
McDonough, W.F.Caciagli, N., Brenan, J.M., McDonough, W.F., Phinney, D.Mineral fluid partitioning of lithium and implications for slab-mantle interaction.Chemical Geology, Vol. 280, 3-4, pp. 384-398.MantleGeochemistry
DS201112-0403
2011
McDonough, W.F.Halama, R., McDonough, W.F., Rudnick, R.L., Bell, K.The lithium isotopic signature of carbonatites.Goldschmidt Conference 2011, abstract p.965.MantleMagmatism
DS201212-0133
2012
McDonough, W.F.Corgne, A., Armstrong, L.S., Keshav, S., Fei, Y., McDonough, W.F., Minarik, W.G., Moreno, K.Trace element partitioning between majoritic garnet and silicate melt at 10-17 Gpa: implications for deep mantle processes.Lithos, Vol. 148, pp. 128-141.Africa, South Africa, GuineaDeposit - Kankan
DS201312-0397
2014
McDonough, W.F.Carlson, R.W., Garnero, E., Harrison, T.M., Li, J., Manga, M., McDonough, W.F., Mukhopadhyay, S., Romanowicz, B., Rubie, D., Williams, Q., Zhong, S.Deep time: how did the early Earth become our modern world?Annual Review of Earth and Planetary Sciences, Vol. 42, pp. 151-178.MantleConvection, composition
DS201312-0877
2013
McDonough, W.F.Sramek, O., McDonough, W.F., Kite, E.S., Lekic, V., Dye, S.T., Zhong, S.Geophysical and geochemical constraints on geoneutrino fluxes from Earth's mantle.Earth and Planetary Science Letters, Vol. 361, pp. 356-366.MantleTomography
DS201412-0100
2014
McDonough, W.F.Carlson, R.W., Garnero, E., Harrison, T.M., Li, J., Manga, M., McDonough, W.F., Mukhopadhyay, S., Romanowicz, B., Rubie, D., Williams, Q., Zhong, S.How did early Earth become our modern world?Annual Review of Earth and Planetary Sciences, Vol. 42, pp. 151-178.MantleMelting
DS201605-0838
2016
McDonough, W.F.Gaschnig, R.M., Rudnick, R.L., McDonough, W.F., Kaufman, A.J., Valley, J., Hu, Z., Gao, S., Beck, M.L.Compositional evolution of the upper continental crust through time, as constrained by ancient glacial diamictites.Geochimica et Cosmochimica Acta, in press available 78p.MantleBulk chemistry

Abstract: The composition of the fine-grained matrix of glacial diamictites from the Mesoarchean, Paleoproterozoic, Neoproterozoic, and Paleozoic, collected from four modern continents, reflect the secular evolution of the average composition of the upper continental crust (UCC). The effects of localized provenance are present in some cases, but distinctive geochemical signatures exist in diamictites of the same age from different localities, suggesting that these are global signatures. Archean UCC, dominated by greenstone basalts and less so komatiites, was more mafic, based on major elements and transition metal trace elements. Temporal changes in oxygen isotope ratios, rare earth elements, and high field strength elements indicate that the UCC became more differentiated and that tonalite-trondhjemite-granodiorite suites became less important with time, findings consistent with previous studies. We also document the concentrations of siderophile and chalcophile elements (Ga, Ge, Cd, In, Sn, Sb, W, Tl, Bi) and lithophile Be in the UCC through time, and use the data for the younger diamictites to construct a new estimate of average UCC along with associated uncertainties.
DS201606-1130
2016
McDonough, W.F.Zhang, Z., Dorfman, S.M., Labidi, J., Zhang, S., Li, M., Manga, M., Stixrude, L., McDonough, W.F., Williams, Q.Primordial metallic melt in the deep mantle.Geophysical Research Letters, Vol. 43, 8, pp. 3693-3697.MantleMelting

Abstract: Seismic tomography models reveal two large low shear velocity provinces (LLSVPs) that identify large-scale variations in temperature and composition in the deep mantle. Other characteristics include elevated density, elevated bulk sound speed, and sharp boundaries. We show that properties of LLSVPs can be explained by the presence of small quantities (0.3-3%) of suspended, dense Fe-Ni-S liquid. Trapping of metallic liquid is demonstrated to be likely during the crystallization of a dense basal magma ocean, and retention of such melts is consistent with currently available experimental constraints. Calculated seismic velocities and densities of lower mantle material containing low-abundance metallic liquids match the observed LLSVP properties. Small quantities of metallic liquids trapped at depth provide a natural explanation for primitive noble gas signatures in plume-related magmas. Our model hence provides a mechanism for generating large-scale chemical heterogeneities in Earth's early history and makes clear predictions for future tests of our hypothesis.
DS201607-1323
2016
McDonough, W.F.Zhang, Z., Dorfman, S.M., Labidi, J., Zhang, S., Li, M., Manga, M., Stixrude, L., McDonough, W.F., Williams, Q.Primordial metallic melt in the deep mantle.Geophysical Research Letters, Vol. 43, 8, pp. 3693-3699.MantleMelting

Abstract: Seismic tomography models reveal two large low shear velocity provinces (LLSVPs) that identify large-scale variations in temperature and composition in the deep mantle. Other characteristics include elevated density, elevated bulk sound speed, and sharp boundaries. We show that properties of LLSVPs can be explained by the presence of small quantities (0.3 -3%) of suspended, dense Fe-Ni-S liquid. Trapping of metallic liquid is demonstrated to be likely during the crystallization of a dense basal magma ocean, and retention of such melts is consistent with currently available experimental constraints. Calculated seismic velocities and densities of lower mantle material containing low-abundance metallic liquids match the observed LLSVP properties. Small quantities of metallic liquids trapped at depth provide a natural explanation for primitive noble gas signatures in plume-related magmas. Our model hence provides a mechanism for generating large-scale chemical heterogeneities in Earth's early history and makes clear predictions for future tests of our hypothesis.
DS201803-0479
2017
McDonough, W.F.Strati, V., Wipperfurth, S.A., Baldoncini, M., McDonough, W.F., Mantovani, F.Perceiving the crust in 3-D: a model integrating geological, geochemical and geophysical data.Geochemistry, Geophysics, Geosystems G3, pp. 4326-Mantlegeophysics

Abstract: Regional characterization of the continental crust has classically been performed through either geologic mapping, geochemical sampling, or geophysical surveys. Rarely are these techniques fully integrated, due to limits of data coverage, quality, and/or incompatible data sets. We combine geologic observations, geochemical sampling, and geophysical surveys to create a coherent 3-D geologic model of a 50 × 50 km upper crustal region surrounding the SNOLAB underground physics laboratory in Canada, which includes the Southern Province, the Superior Province, the Sudbury Structure, and the Grenville Front Tectonic Zone. Nine representative aggregate units of exposed lithologies are geologically characterized, geophysically constrained, and probed with 109 rock samples supported by compiled geochemical databases. A detailed study of the lognormal distributions of U and Th abundances and of their correlation permits a bivariate analysis for a robust treatment of the uncertainties. A downloadable 3-D numerical model of U and Th distribution defines an average heat production of math formula µW/m3, and predicts a contribution of math formula TNU (a Terrestrial Neutrino Unit is one geoneutrino event per 1032 target protons per year) out of a crustal geoneutrino signal of math formula TNU. The relatively high local crust geoneutrino signal together with its large variability strongly restrict the SNO+ capability of experimentally discriminating among BSE compositional models of the mantle. Future work to constrain the crustal heat production and the geoneutrino signal at SNO+ will be inefficient without more detailed geophysical characterization of the 3-D structure of the heterogeneous Huronian Supergroup, which contributes the largest uncertainty to the calculation.
DS1998-0963
1998
McDougallMatsumoto, T., Honda, M., McDougall, O'Reilly, S.Y.Noble gases in an anhydrous lherzolites from the Newer Volcanics, southeastern Australia: Mid Ocean Ridge Basalt (MORB) like...Geochimica et Cosmochimica Acta, Vol. 62, No. 14, July, pp. 2521-34.AustraliaMantle - subcontinental, Geochemistry
DS1994-1149
1994
McDougall, D.McDougall, D.Diamond tests said positive.. Vera Cruz Minerals INc. kimberlite strike south of New Liskeard.Kirkland Lake Northern Daily News, March 3, p. 8A.OntarioNews item, Vera Cruz Minerals Inc.
DS1960-0479
1964
Mcdougall, I.Mcdougall, I., Green, D.H.Excess Radiogenic Argon in Pyroxenes and Isotopic Ages on Minerals from Norwegian Eclogites.Norske Geol. Tidsskr., Vol. 44, PP. 183-196.Norway, ScandinaviaIsotope
DS1970-0212
1970
Mcdougall, I.Wellman, P., Cundari, A., Mcdougall, I.Potassium-argon Ages for Leucite Bearing Rocks from New South Wales.Royal Society. NEW SOUTH WALES Transactions, Vol. 103, PP. 103-107.Australia, New South WalesLeucite, Geochronology
DS1970-1005
1974
Mcdougall, I.Wellman, P., Mcdougall, I.Cainozoic Igneus Activity in Eastern AustraliaTectonophysics, Vol. 23, PP. 49-65.Australia, New South WalesKimberlite, Basalt
DS1982-0152
1982
Mcdougall, I.Compston, W., Mcdougall, I., Wyborn, D.Possible 2 Stage Sr 87 Evolution in the Stockdale RhyoliteEarth And Planetary Sci. Letters, Vol. 61, No. 2, Dec., PP. 297-302.United States, Kansas, Central StatesStrontium, Stockdale
DS1994-1888
1994
McDougall, I.Watkins, R.T., McDougall, I., Le Roex, A.P.K-Ar ages of the Brandberg and Okenyenya igneous complexes, northwesternNamibiaGeologische Rundschau, Vol. 83, No. 2, July pp. 348-356NamibiaIgneous complexes, Geochronology
DS200612-0891
2006
McDougall, R.A.McDougall, R.A.Dealing with mineral disclosure and other key issues in financing transactions.Insight Mining Business and Investment Forum, Held June 5-6, Toronto, 17p. Xerox of slides onlyCanadaEconomics - legal - not specific to diamonds
DS1990-1011
1990
McDougall, T.J.McDougall, T.J.Bulk properties of hot smoker plumesEarth and Planetary Science Letters, Vol. 99, pp. 185-194GlobalGeochemistry, Mantle plumes
DS1990-0867
1990
McDowall, G.Koketso, H., McDowall, G.Geophysical response of some kimberlite pipes in the Jwaneng area, southernBotswana52nd. Meeting Of The European Association Of Exploration Geophysicists, Vol. 52, pp. 195-196BotswanaGeophysics -magnetics, Jwaneng
DS1991-1103
1991
McDowall, G.McDowall, G., Koketso, H.Radon emanometry over some kimberlites and lamproites in southern and western BotswanaEuropean Journal of Exploration Geophysics, Abstract No. D009 p. 332BotswanaGeophysics -Radon, Lamproites
DS1970-0351
1971
Mcdowell, F.W.Mcdowell, F.W.K-ar Ages of Igneus Rocks from the Western United StatesIsochron West., No. 2, PP. 1-16.GlobalLeucite Hills, Leucite, Rocky Mountains
DS1970-0352
1971
Mcdowell, F.W.Mcdowell, F.W., Roden, M.F., Arculus, R.J., Smith, D.Potassic Volcanism and Associated Inclusion on the Coloradoplateau.Geological Society of America (GSA), Vol. 10, P. 116, (abstract.).Colorado PlateauKimberlite, Rocky Mountains
DS1986-0358
1986
McDowell, F.W.Henry, C.D., McDowell, F.W., Price, J.G., Smyth, R.C.Compilation of potassium argon ages of Tertiary igneous rocks,Trans PecosTexasTexas Bur. Econ. Geol, Geol. Circular, No. 86-2, 20pGlobalGeochronology
DS1987-0457
1987
McDowell, F.W.McDowell, F.W., Roden, M.F., Smith, D.Comments on tectonic implications of the age, composition and orientation of lamprophyre dikes, Navajo volcanic field, Arizona #2Earth and Planetary Science Letters, Vol. 80, No. 3-4, pp. 415-420ArizonaUSA, Tectonics
DS1991-0346
1991
McDowell, F.W.Davis, L.L., McDowell, F.W., Smith, D., Walker, N.W.Potassic, mafic rocks at Twin Buttes, ColoradoEos, Spring Meeting Program And Abstracts, Vol. 72, No. 17, April 23, p. 295ColoradoMinette
DS1996-0338
1996
McDowell, F.W.Davis, L.L., Smith, D., McDowell, F.W., Walker, N.W., BorgEocene potassic magmatism at Two Buttes, Colorado, with implications for Cenozoic tectonics and magma generationGeological Society of America (GSA) Bulletin., Vol. 108, No. 12, Dec. pp. 1567-1579.ColoradoAlkaline rocks, Tectonics
DS2000-0250
2000
McDowell, F.W.Dunn, D., Smith, D., McDowell, F.W., Bergman, S.C.Mantle and crustal xenoliths from the Prairie Creek lamproite province, Arkansas.Geological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-386.ArkansasXenoliths, Deposit - Black Lick, Twin Knobs
DS201112-1060
2011
McEachren, J.Tsuji, L.J.S., McCarthy, D.D., Whitelaw, G.S., McEachren, J.Getting back to basics: the Victor diamond mine environmental assessment scoping process and the issue of family based traditional lands versus reg. traplinesImpact assessment and Project Appraisal, March Vol. 29, no. 1, pp. 37-47.Canada, Ontario, AttawapiskatLegal
DS201212-0736
2011
McEachren, J.Tsuji, L.J.S., McCarthy, D.D., Whielaw, G.S., McEachren, J.Getting back to basics: the Victor diamond mine environmental assessment scoping process and the issue of family based traditional lands versus traplines.Impact Assessment and Project Aapraisal, Vol. 29, 1, pp. 37-47.Canada, Ontario, AttawapiskatEnvironment
DS1996-0925
1996
McElfish, J.M.McElfish, J.M., Bernstein, T., Bass, S.P., Sheldon, E.Hard rock mining: ColoradoEnvironmental Law Institute, Chapter 4, pp. 103-158ColoradoMining laws, Environmental
DS1996-0926
1996
MCElfish, J.M.MCElfish, J.M., Berstein, T., Bassm S., Sheldon, E.Hard rock mining: state approaches to environmental protection.... Coloradochapter.Environmental Law Institute, Chapter 4, pp. 103-158.ColoradoLegal overview, Environmental overview
DS202006-0918
2020
McElhenny, G.Eaton-Magana. S., McElhenny, G., Breeding, C.M., Ardon, T.Comparison of gemological and spectroscopic features in type IIa and Ia natural pink diamonds.Diamonds & Related Materials, Vol. 105, 13p. PdfMantlenitrogen

Abstract: The majority of natural pink diamonds have a color origin due to absorption from a broad 550?nm band that has been associated with plastic deformation. One consistent feature in the photoluminescence spectra of these pink diamonds is a wide emission band extending from ~600 to 750?nm, with a series of smaller oscillations overlaid on the larger emission band. This "pink emission band" is seen in diamonds colored by the 550?nm absorption band; the absorption band often, but not always, shows similar oscillations at ~600?nm (called the 609?nm system by previous researchers). This emission band served as a proxy for the 550?nm absorption band as we performed spatial mapping to chronicle the differences between the uniform coloration in type IIa pink diamonds and the pronounced banding in type Ia pink diamonds. We also used Raman spectroscopy to identify the internal crystal inclusions present in type IIa pink diamonds and determined that the majority have a sub-lithospheric origin.
DS202102-0183
2020
McElhenny, G.Eaton-Magana, S., McElhenny, G.Diamond with cavities showing radiation evidence. Gems & Gemology , Vol. 56, 1, pp. 126-127Technologydiamond inclusions

Abstract: The Carlsbad laboratory recently examined a 0.70 ct, E-color round brilliant. Infrared spectroscopy showed this to be a type IIa diamond, so we performed a variety of additional spectroscopy and imaging to verify its natural origin. This diamond also had I1 clarity due to a large inclusion under the table (figure 1). Raman analysis of the inclusions verified that this crystal was a metastable composite of the minerals wollastonite (CaSiO3) and CaSiO3-breyite (E.M. Smith et al., “The very deep origin of the world’s biggest diamonds,” Winter 2017 G&G, pp. 388-403), which indicates a sublithospheric origin. These minerals are believed to be the lower-pressure phases of CaSiO3-perovskite. Around these minerals were large disk-like graphitic fractures indicating inclusion expansion as pressures on the diamond reduced during exhumation from the mantle. The other inclusion present was unidentifiable due to its graphitic casing. Recent research of inclusions in other type II diamonds shows that many, if not most, have a superdeep origin (again, see Smith et al., 2017). This stone is one more example of diamonds forming at incredible depths of 360-750 km before being transported to near the surface.
DS202102-0208
2020
McElhenny, G.McElhenny, G., Turner, M., Breeding, C.M.Corundum inclusions in gem diamond.Gems & Gemology , Vol. 56, 1, pp. 129-131.Technologydiamond inclusions

Abstract: Inclusions can tell us a great deal about a diamond’s formation history. Inclusions such as olivine, garnet, and chromite are more common, while others such as kyanite, zircon, and corundum (Al2O3) can be quite rare. Regardless of their rarity, diamond inclusions are often quite fascinating as they trap a small bit of the deep earth that cannot otherwise be sampled.
DS1960-0686
1966
Mcelhinney, M.W.Jones, D.L., Mcelhinney, M.W.Paleomagnetic Correlation of Basic Intrusions in the Precambrian of Southern Africa.Journal of Geophysical Research, Vol. 71, No. 2, PP. 543-552.South AfricaRelated Rocks, Paleomagnetics
DS1991-1006
1991
Mcelhinny, M.W.Lock, J., Mcelhinny, M.W.The global paleomagnetic database: design, installation and use withoracleSurveys in Geophysics, Vol. 12, No. 4-5, July pp. R5-R491GlobalPaleomagnetics, Database
DS1993-1000
1993
McElhinny, M.W.McElhinny, M.W., Lock, JoGlobal paleomagnetic database.. supplement number one: update to 1992Surveys in Geophysics, Vol. 14, No. 3, May pp. 303-GlobalGeophysics, Paleomagnetism
DS2003-0910
2003
McElhinny, M.W.McElhinny, M.W., Powell, C.M., Pisarevsky, S.A.Paleozoic terranes of eastern Australia and the drift history of GondwanaTectonophysics, Vol. 362, 1-4, pp. 41-65.AustraliaTectonics
DS1986-0550
1986
McElmore, V.T.McElmore, V.T.Geology and associated fenitization of the Lemitar carbonatites central New Mexico, USAGeological Association of Canada (GAC) Annual Meeting, Vol. 11, p. 100. (abstract.)New MexicoCarbonatite
DS1988-0452
1988
McElmore, V.T.McElmore, V.T.Geochemistry of carbonatites from New MexicoV.m. Goldschmidt Conference, Program And Abstract Volume, Held May, p. 60. AbstractNew MexicoBlank
DS2003-1021
2003
McElroy, R.Nowicki, T.E., Crawford, B., Dyck, D., Carlson, J., McElroy, R., Helmstaedt, H.A review of the geology of kimberlite pipes of the Ekati property, Northwest8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractNorthwest TerritoriesGeology, Deposit - Ekati
DS200412-1450
2003
McElroy, R.Nowicki, T.E., Crawford, B., Dyck, D., Carlson, J., McElroy, R., Helmstaedt, H., Oshust, P.A review of the geology of kimberlite pipes of the Ekati property, Northwest Territories, Canada8 IKC Program, Session 1, AbstractCanada, Northwest TerritoriesGeology Deposit - Ekati
DS200612-0892
2006
McElroy, R.McElroy, R., Nowicki, T., Dyck, D., Carlson, J., Todd, J., Roebuck, S., Crawford, B., Harrison, S.The geology of the PAnd a kimberlite Ekati mine, Canada.Emplacement Workshop held September, 5p. extended abstractCanada, Northwest TerritoriesDeposit - Panda geology
DS2003-0911
2003
McElroy, R.E.McElroy, R.E., Nowicki, T.E., Dyck, D.R., Carlson, J.A., Todd, J.K., RoebuckThe geology of the PAnd a kimberlite, Ekati diamond mine, Canada8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractNorthwest TerritoriesKimberlite geology and economics, Deposit - Panda
DS1996-0927
1996
McEnroe, S.McEnroe, S.A Barremenian-Aptian (Early Cretaceous) North American paleomagnetic reference pole.Journal of Geophysical Research, Vol. 101, No. B7, July 10, pp. 15, 819-36.North America, CanadaPaleomagnetics
DS1992-1030
1992
McEnroe, S.A.McEnroe, S.A., Brown, L.L.Implications for the Mesozoic APW for North America from intrusions and sedimentary rocks in New EnglandEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 95GlobalCretaceous intrusions, Paleomagnetics
DS1994-1150
1994
McEnroe, S.A.McEnroe, S.A.Does the changing chemistry of Mesozoic mafic dikes from Connecticut to Maine reflect changing plate conditions.Geological Society of America Abstracts, Vol. 26, No. 3, March, p. 61. AbstractGlobalTectonics, Dikes
DS1996-0928
1996
McEnroe, S.A.McEnroe, S.A.North America during the lower Cretaceous - new paleomagnetic constraints from intrusions New England.Geophysical Journal, Vol. 126, No. 2, Aug., pp. 477-494.Canada, United StatesGeophysics -paleomagnetics, Polar wandering
DS2001-0755
2001
McEnroe, S.A.McEnroe, S.A., Harrison, R.J., Robinson, P., GollaEffect of fine scale microstructures in titanohematite on the acquisition and stability of natural remnant...Journal of Geophysical Research, Vol. 106, No. 12, pp. 30,523-46.SwedenCrustal magnetism
DS2001-0756
2001
McEnroe, S.A.McEnroe, S.A., Robinson, P., Panish, P.T.Aeromagnetic anomalies, magnetic petrology, and rock magnetism of hemo-ilmenite magnetite rich cumulates...Amer. Min., Vol. 86, pp. 1447-68.NorwayGeophysics - magnetics - not specific to diamonds, Sokndal region
DS200412-1269
2004
McEnroe, S.A.McEnroe, S.A., Langenhorst, F., Robinson, P., Bromiley, G.D., Shaw, C.S.J.What is magnetic in the lower crust?Earth and Planetary Science Letters, Vol. 226, 1-2, Sept. 30, pp.175-192.MantleMagnetic anomalies, hematite-ilmenite, Curie isotherm
DS200612-0869
2005
McEvoy, F.Marker, B.R., Petterson, M.G., McEvoy, F., Stephenson, M.H.Sustainable minerals operations in the Developing World.Geological Society of London Special Publication, SP 250, 256p. aaprox. 160.00GlobalBook - resources
DS200612-0893
2006
McEwen, C.McEwen, C.Marketing ... following through.Canadian Diamonds, Winter, p. 12. (1p.)Canada, Northwest TerritoriesNews item - branding
DS1975-1144
1979
Mcewen, G.Mcewen, G.The Proceedings of a Seminar on Geophysics and the Exploration of the Kalahari.Botswana Geological Survey, Bulletin. No. 22, 423P.Botswana, South AfricaGeophysics, Tectonics
DS1996-1400
1996
McEwin, A.J.Tarlowski, C., McEwin, A.J., Reeves, C.V., Barton, C.E.Dewarping the composite aeromagnetic anomaly map of Australia using controltraverses and base stationsGeophysics, Vol. 61, No. 3, May-June pp. 696-705AustraliaGeophysics -aeomagnetics, Composite anomaly map
DS1983-0440
1983
Mcewing, C.E.Mcewing, C.E., Rees, C.E., Thode, H.G.Sulphur Isotope Ratios in the Canyon Diablo Metallic Spheroids.Meteoritics, Vol. 18, No. 3, SEPT. 30TH. PP. 171-178.United States, Arizona, Colorado PlateauIsotope, Meteor
DS2003-0912
2003
McFadden, N.McFadden, N.Diamonds in the rough: a new industry emerging in Canada's NorthCanada Forum: Held Nov. 204, Joint Ventures-Joint Rewards. The resource, [email protected] 180p. binder $ 120.00Northwest TerritoriesConference - talk
DS200412-1270
2003
McFadden, N.McFadden, N.Diamonds in the rough: a new industry emerging in Canada's North.Canada Forum: Held Nov. 204, Joint Ventures-Joint Rewards. The resource industry and aboriginal development co, info @canadaforum.com 180p. binder $ 120.00Canada, Northwest TerritoriesConference - talk
DS1992-1031
1992
McFadden, P.McFadden, P.Geomagnetism: reversal ideas up-endedNature, Vol. 356, No. 6368, April 2, pp. 381-382GlobalGeomagnetisM.
DS1970-0762
1973
Mcfadden, P.L.Mcfadden, P.L.A Paleomagnetic Study of the de Beers Diamond Mine1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 221-223.South AfricaSensing
DS1975-0134
1975
Mcfadden, P.L.Mcfadden, P.L.A Paleomagnetic Study of Cretaceous Kimberlite Occurrences In the Northern Cape.Salisbury: Ph.d. Thesis, University Rhodesia., South AfricaKimberlite, Geophysics
DS1975-0567
1977
Mcfadden, P.L.Mcfadden, P.L.A Paleomagnetic Determination of the Emplacement Temperature of Some South African Kimberlites.Geophys. Journal of Roy. Astron. Soc., Vol. 50, PP. 587-604.South AfricaKimberlite, Geophysics
DS1975-0568
1977
Mcfadden, P.L.Mcfadden, P.L., Jones, D.L.The Paleomagnetism of Some Upper Cretaceous Kimberlite Occurrences in South Africa.Earth and Planetary Science Letters, Vol. 34, No. 1, PP. 125-135.South AfricaKimberlite, Geophysics
DS1994-1173
1994
McFadden, P.L.Merrill, R.T., McFadden, P.L.Geomagnetic field stability: reversal events and excursionsEarth and Planetary Science Letters, Vol. 121, No. 1-2, January pp. 57-70GlobalPaleomagnetics, Geomagnetics
DS1995-1210
1995
McFadden, P.L.McFadden, P.L., Merrill, R.T.History of the earth's magnetic field and possible connections to core-mantle boundary processes.Journal of Geophysical Research, Vol. 100, No. B1, Jan. 10, pp. 307-316.MantleMagnetism, Boundary
DS1995-1239
1995
McFadden, P.L.Merrill, R.T., McFadden, P.L.Dynamo theory and PaleomagnetismJournal of Geophysical Research, Vol. 100, No. B1, Jan. 10, pp. 317-326.MantleMagnetism, Paleomagnetism -review
DS1992-1553
1992
McFadyen, D.Thurston, P.C., McFadyen, D.Geological interpretation and mineral potential of the basement underlying part of the Hudson Bay LowlandsOntario Geological Survey Open File, No. 5826, 12p. 12 coloured maps folio $ 194.00OntarioGeophysics, magnetics, Hudson Bay Lowlands
DS1975-0596
1977
Mcfadyen, D.A.Paterson, N.R., Mcfadyen, D.A., Turkeli, A.Geophysical Exploration for Kimberlites with Special Reference to Lesotho.Geophysics, Vol. 42, No. 7, P. 1531, (abstract.).South Africa, LesothoKimberlite, Geophysics
DS1985-0432
1985
Mcfarland, J.D.Mcfarland, J.D., Stolarz, T.The Geologic History of the Crater of Diamonds State ParkArkansaw STATE PARKS, 11P.United States, Gulf Coast, Arkansas, PennsylvaniaHistory
DS201703-0424
2017
McFarlane, C.R.M.LaFlamme, C., McFarlane, C.R.M., Fisher, C.M., Kirkland, C.L.Multi-mineral geochronology: insights into crustal behaviour during exhumation of an orogenic root.Contributions to Mineralogy and Petrology, in press available, 18p.CanadaCraton, Rae, Hearne
DS201707-1351
2017
McFarlane, C.R.M.Mitchell, R., Chudy, T., McFarlane, C.R.M., Wu, F-Y.Trace element and isotopic composition of apatite in carbonatites from the Blue River area ( British Columbia, Canada) and mineralogy of associated silicate rocks. Verity, Fir, Gum, Howard Creek, FelixLithos, in press available, 64p.Canada, British Columbiacarbonatite - Blue River

Abstract: Apatites from the Verity, Fir, Gum, Howard Creek and Felix carbonatites of the Blue River (British Columbia, Canada) area have been investigated with respect to their paragenesis, cathodoluminescence, trace element and Sr–Nd isotopic composition. Although all of the Blue River carbonatites were emplaced as sills prior to amphibolite grade metamorphism and have undergone deformation, in many instances magmatic textures and mineralogy are retained. Attempts to constrain the U–Pb age of the carbonatites by SIMS, TIMS and LA–ICP-MS studies of zircon and titanite were inconclusive as all samples investigated have experienced significant Pb loss during metamorphism. The carbonatites are associated with undersaturated calcite–titanite amphibole nepheline syenite only at Howard Creek although most contain clasts of disaggregated phoscorite-like rocks. Apatite from each intrusion is characterized by distinct, but wide ranges, in trace element composition. The Sr and Nd isotopic compositions define an array on a 87Sr/86Sr vs²Nd diagram at 350 Ma indicating derivation from depleted sub-lithospheric mantle. This array could reflect mixing of Sr and Nd derived from HIMU and EM1 mantle sources, and implies that depleted mantle underlies the Canadian Cordillera. Although individual occurrences of carbonatites in the Blue River region are mineralogically and geochemically similar they are not identical and thus cannot be considered as rocks formed from a single batch of parental magma at the same stage of magmatic evolution. However, a common origin is highly probable. The variations in the trace element content and isotopic composition of apatite from each occurrence suggest that each carbonatite represents a combination of derivation of the parental magma(s) from mineralogically and isotopically heterogeneous depleted mantle sources coupled with different stages of limited differentiation and mixing of these magmas. We do not consider these carbonatites as primary direct partial melts of the sub-lithospheric mantle which have ascended from the asthenosphere without modification of their composition.
DS1991-1104
1991
McFarlane, M.J.McFarlane, M.J.Some sedimentary aspects of lateritic weathering profile development in the major bioclimatic zones of tropical AfricaJournal of Sth. African Earth Sciences, Vol. pp. 267-282Africa, UgandaLaterites, Geomorphology
DS201810-2355
2018
McFarlane, M.J.McFarlane, M.J., Long, C.W., Coetzee, S.H.Lightning induced beads, 'fulguroids', associated with kimberlite eruptions in the Kalahari, Botswana.International Journal of Earth Sciences, Vol. 107, 7, pp. 2627-2633.Africa, Botswanakimberlites

Abstract: Glassy beads were found in the sand cover associated with known and suspected kimberlites on the Kalahari plateau, Botswana. Morphology and chemistry were examined by ESEM and EDAX. The polymetallic and quartzose "beads", here described for the first time and termed fulguroids, formed at very high temperatures, well in excess of those reached by the kimberlites. They solidified in free fall. We propose that they were melted in the atmosphere by lightning strikes on Kalahari overburden entrained when the kimberlites erupted.
DS1989-1613
1989
McFeeley, P.Wheeler, J.O., McFeeley, P.New edition of the tectonic assemblage map of the Canadian Cordillera and adjacent United StatesGeological Society of Canada (GSC) Forum 1989, P. 24 abstractCanadaMap, Tectonic
DS1987-0788
1987
McFeely, P.Wheeler, J.O., McFeely, P.Tectonic assemblage map of the Canadian Cordillera and parts of the United states of America.Geological Survey of Canada (GSC) Open file, No. 2369, 1:2, 000, 000Alberta, CordilleraMap, Tectonics
DS1993-1001
1993
McGarr, A.McGarr, A.Induced seismicity.. reprint from Pure and Applied GeophysicsSpringer Verlag, 460p. approx. $ 120.00GlobalBook -ad, Geophysics -seismics
DS2003-0913
2003
McGaughey, J.McGaughey, J.Detectability of mineral deposits with airborne gravity gradiometryPdac Abstract 2003, March 12, 1p.GlobalGeophysics - density
DS200612-1350
2006
McGaughey, J.Sprague, K., De Kemp, E., Wong, W., McGaughey, J., Perron, G., Barrie, T.Spatial targeting using queries in a 3 D GIS environment with application to mineral exploration.Computers & Geosciences, Vol.32, 3, pp. 396-418.TechnologyComputer - programs
DS2003-0914
2003
McGaughey, W.J.McGaughey, W.J., Perron, G., Bellefleur, G.Downhole seismic imaging technology for deep mineral exploration. (mentions VictorOntario Exploration and Geoscience Symposium, Dec. 8,9,10th., Abstracts p. 16-17. (1/4p.)Ontario, AttawapiskatGeophysics - seismic DS
DS200412-1271
2003
McGaughey, W.J.McGaughey, W.J., Perron, G., Bellefleur, G.Downhole seismic imaging technology for deep mineral exploration. (mentions Victor pipe)Ontario Exploration and Geoscience Symposium, Dec. 8,9,10th., Abstracts p. 16-17. (1/4p.)Canada, Ontario, Attawapiskat, James Bay LowlandsGeophysics - seismic DS
DS200712-0066
2005
McGaughty, J.Bellefleur, G., Matthews, L., Roberts,B., McMonnies, B., Salisbury, M., Snyder, D., Perron, G., McGaughty, J.Downhole seismic imaging of the Victor kimberlite, James Bay Lowlands, Ontario: a feasibility study.Geological Survey of Canada Current Research, 2005- C1, 7p.Canada, OntarioGeophysics - seismics
DS201212-0454
2012
McGee, B.McGee, B., Collins, A.S., Trindada, R.I.F.G'Day Gondwana - the final accretion of a supercontinent: U Pb ages from the post-orogenic Sao Vincente Granite, northern Paraguay Belt, Brazil.Gondwana Research, Vol 21, 2-3, pp. 316-322.South America, BrazilAccretion
DS201412-0568
2015
McGee, B.McGee, B., Collins, A.S., Trindade, R.I.F., Jourdan, F.Investigating mid-Edicaran glaciation and final Gondwana amalgamation using coupled sedimentology and 40 Ar/39Ar detrital muscovite provenance from the Paraguay Belt, Brazil.Sedimentology, Vol. 62, 1, pp. 130-154.South America, BrazilGeomorphology
DS201809-1992
2018
McGee, B.Babinski, M., McGee, B., do Couto Tokashiki, C., Tassinari, C.C.G., Souza Saes, G., Cavalante Pinho, F.E.Comparing two arms of an orogenic belt during Gondwana amalgamation: age and provenance of Cuiaba Group, northern Paraguay, Brazil.South American Earth Sciences, Vol. 85, pp. 6-42.South America, Brazilgeochronology

Abstract: The Cuiabá Group is the basal part of the sequence of passive margin sediments that unconformably overly the Amazonian Craton in central Brazil. Despite these rock's importance in understanding Brazil's path in the supercontinent cycle from Rodinia to Gondwana and their potential record of catastrophic glaciation their internal stratigraphy and relationship to other units is still poorly understood. The timing of deposition and source areas for the subunits of the Cuiabá Group sedimentary rocks are investigated here using integrated U-Pb and Sm-Nd isotope data. We sampled in the northern Paraguay Belt, a range that developed in response to the collision between the Amazonian Craton, the Rio Apa Block, the São Francisco Craton and the Paranapanema Block. 1125 detrital zircon LA-ICPMS U-Pb ages were calculated and 22 whole rock samples were used for Sm-Nd isotope analysis. The U-Pb ages range between Archean and Neoproterozoic and the main source is the Sunsás Province. Moving up stratigraphy there is a subtle increase in slightly younger detritus with the youngest grain showing an age of 652?±?5 Ma, found at the top of the sequence. The age spectra are similar across each of the sampled units and when combined with the Sm-Nd data, indicate that the source of the detritus was mostly similar throughout deposition. This is consistent with the analysis here that indicates sedimentation occurred in a passive margin environment on the southern margin of the Amazonian Craton. The maximum depositional age of 652?±?5 Ma along with the age of the overlying cap carbonate of the Mirassol d’Oeste Formation suggests that part of this section of sediments were deposited in the purportedly global ?636 Ma Marinoan glaciation, although we give no sedimentological evidence for glaciation in the study area. Compared to the southern Paraguay Belt where no direct age constraints exist, the glacial epoch could be either Cryogenian or Ediacaran. In addition, available data in the literature indicates a diachronous evolution between the northern and southern arms of the Paraguay Belt in the final stages of deposition and deformation.
DS1980-0229
1980
Mcgee, E.S.Mcgee, E.S., Hearn, B.C.JR.Garnets as Tracer Minerals for Montana KimberlitesGeological Society of America (GSA), Vol. 12, No. 6, P. 280, (abstract.).MontanaKimberlite, Rocky Mountains
DS1981-0211
1981
Mcgee, E.S.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotites from the Williams Kimberlites, North Central Montana.Geological Society of America (GSA), Vol. 13, No. 4, P. 199, (abstract.).United States, Montana, Rocky MountainsBlank
DS1982-0267
1982
Mcgee, E.S.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotites from Williams Kimberlites, North-centralmontana, United States (us)Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 218, (abstract.).United States, Montana, Rocky MountainsKimberlite, Alnoite, Diatreme, Lherzolite, Harzburgite, Dunite
DS1982-0268
1982
Mcgee, E.S.Hearn, B.C.JR., Mcgee, E.S.Garnet in Montana Diatremes: a Key to Prospecting for Kimberlites.United States Geological Survey (USGS) OPEN FILE REPORT., No. 82-722, 45P.United States, Montana, Rocky MountainsKimberlite, Analyses, Williams, Big Slide, Bulletinwacker Coulee
DS1982-0423
1982
Mcgee, E.S.Mcgee, E.S., Hearn, B.C. JR.Inclusions in the Lake Ellen Kimberlite, Northern Michigan, united States (us)Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 220, (abstract.).Michigan, United States, Great LakesKimberlite, Geophysics, Magnetic, Groundmag
DS1983-0299
1983
Mcgee, E.S.Hearn, B.C.JR, Mcgee, E.S.Garnets in Montana Diatremes; a Key to Prospecting for Kimberlites.United States Geological Survey (USGS) Bulletin., No. 1604, 33P.United States, Montana, Rocky MountainsMineral Chemistry, Inclusions, Microprobe, Analyses
DS1983-0300
1983
Mcgee, E.S.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotites from Williams Kimberlites, North Centralmontana, United States (us)United States Geological Survey (USGS) OPEN FILE., No. 83-172, 26P.United States, Montana, Rocky MountainsAlnoite, Xenoliths, Petrography, Lherzolite, Geology, Diatreme
DS1983-0441
1983
Mcgee, E.S.Mcgee, E.S., Hearn, B.C.JR.Lake Ellen Kimberlite, Michigan, United States (us)United States Geological Survey (USGS) OPEN FILE., No. 83-156, 22P.United States, Michigan, Great LakesXenolith, Megacrysts, Petrology, Petrography, Inclusions, Kimberite
DS1984-0351
1984
Mcgee, E.S.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotite from Williams Kimberlites, North Central Montana, United States (us)Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 57-70.United States, Rocky Mountains, MontanaInclusions, Textures, Petrography, Mineral Chemistry, Analyses
DS1984-0503
1984
Mcgee, E.S.Mcgee, E.S., Hearn, B.C.JR.The Lake Ellen Kimberlite, Michigan, United States (us)Proceedings of Third International Kimberlite Conference, Vol. 1, PP. 143-154.United States, Michigan, Great LakesProspecting, History, Xenocrysts, Mineralogy, Analyses, Inclusion
DS1985-0277
1985
Mcgee, E.S.Hearn, B.C.JR., Mcgee, E.S.Research on Kimberlites and Applications to Diamond Prospecting.United States Geological Survey (USGS) INF. Circular, No. 949, PP. 22-23.United States, Montana, Michigan, Colorado, Great Lakes, Rocky MountainsCurrent Review
DS1986-0551
1986
McGee, E.S.McGee, E.S.Potential for diamonds in kimberlites from Michigan and Montana as indicated by garnet xenocrysts compositionsGeological Society of America (GSA) Abstract Volume, Vol. 18, No. 6, p. 692. (abstract.)MontanaPetrology
DS1986-0552
1986
McGee, E.S.McGee, E.S.Garnet megacrysts of the Williams diatremes, north central MontanaAmerican Mineralogist, Vol. 71, pp. 674-681MontanaPetrology
DS1986-0553
1986
McGee, E.S.McGee, E.S., Hearn, B.C. Jr.Carbonates xenoliths from the Macdougal Springs mica peridotitediatreme:inferences for upper mantle conditions in north central MontanaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 291-293MontanaBlank
DS1987-0181
1987
McGee, E.S.Eggler, D.H., Dudas, F.O., Hearn, B.C., McCallum, M.E., McGee, E.S.Lithosphere of the continental United States: Xenoliths in Kimberlites and other alkaline magmasin: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 41-58United States, Montana, Colorado Wyoming, Kansas, Arkansas, MichiganTennessee, Kentucky, Pennsylvania, New York, Wyoming, Arizon
DS1987-0286
1987
McGee, E.S.Hearns, B.C.Jr., McGee, E.S.Crust and upper mantle beneath the Northern Plains; evidence from MontanaxenolithsUnited States Geological Survey (USGS) Circular No.956 Geophysics and petrology of the deep crust and upper, pp. 32-34MontanaXenoliths
DS1988-0453
1988
McGee, E.S.McGee, E.S.Potential for diamond in kimberlites from Michigan and Montanaas indicated by garnet xenocryst compositionsEconomic Geology, Vol. 83, No. 2, March-April pp. 428-432Michigan, MontanaBlank
DS1989-0984
1989
McG
 
 

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