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SDLRC - Scientific Articles all years by Author - G-Gh


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 - G-Gh
Posted/
Published
AuthorTitleSourceRegionKeywords
DS201912-2805
2019
G, M.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.
DS201212-0215
2012
G & G eBriefG & G eBriefGemesis CVD grown synthetic diamonds characterized.Gems & Gemology Lab Notes, 1p.TechnologySynthetic diamonds
DS201212-0216
2012
G & G eBriefG & G eBriefLarge artifically irradiated yellow diamond.Gems & Gemology Lab Notes, 1p.TechnologyDiamonds - irradition
DS201212-0217
2012
G & G eBriefG & G eBriefType Iib CVD synthetic diamond.G & G Brief, August 1/2p.TechnologyDiamond - synthetics
DS201212-0218
2012
G & G eBriefG & G eBriefDiamond type. Brief summary of 1a, 1b, 11a and 11b.G & G Brief, Sept 12, 1/3p.TechnologyDiamond category
DS201212-0219
2012
G & G eBriefG & G eBriefDiamond basics: part 2. Fluorescence and phosphoresence.G & G Brief, 1/4p.TechnologyDiamond - radiation
DS201212-0220
2012
G & G eBriefG & G eBriefMulti-treated yellowish green diamond.G & G Brief, Vol. 3, 8, May 8, 1/4p.TechnologyHPHT treatment
DS201212-0221
2012
G & G ebriefG & G ebriefDiamond with unusual omphacite and pyrope-almandine garnet inclusion.G & G Brief, Vol. 4, 2, Nov. 14, 1/4p.TechnologyDiamond inclusion
DS201212-0222
2012
G & G ebriefG & G ebriefDiamond basics: part 3: how color happens in diamonds.G & G Brief, Vol. 4, 2, Nov. 14, 1/4p.TechnologyDiamond colour
DS201212-0223
2012
G & G eBriefG & G eBriefHPHT grown synthetic diamond - DiamondViewG & G Brief, Vol. 3, 4, Jan. 14, 1/2p.TechnologyDiamond synthesis
DS201212-0224
2012
G & G eBriefG & G eBriefGlobal diamond demand stays strong. G & G Brief, Vol. 3, 4, Jan. 14, 1/2p.GlobalEconomics
DS201312-0286
2012
G & G ebriefG & G ebriefDiamond with diopside-pyrope contact inclusion pair.Gems & Gemology, Vol. 4, 3, 1/4p.TechnologyDiamond inclusion
DS201312-0287
2013
G & G ebriefsG & G ebriefsArtificially irradiated brown diamond.Gems & Gemology, 1/2p.TechnologyDiamond - colour
DS201201-0842
2011
G & G Lab notesG & G Lab notesGem quality CVD synthetic diamonds from Gemesis.Gems & Gemology, Vol. 47, 3, pp. 227-228.TechnologyGemesis CVD
DS201201-0843
2011
G & G Lab notesG & G Lab notesBlack diamond, colored by strong plastic deformation.Gems & Gemology, Vol. 47, 3, pp. 223.TechnologyBlack diamond
DS201201-0844
2011
G & G Lab notesG & G Lab notesColorless untreated diamonds with high levels of strain. Type IIaGems & Gemology, Vol. 47, 3, pp. 224-5.TechnologyDiamond morphology
DS201604-0606
2015
G & G Lab notesG & G Lab notesGraphite inclusions forming octahedral outline in diamond.Gems & Gemology Lab Notes, Vol. 51, 4, winter pp. 428-429.TechnologyDiamond inclusions
DS201604-0607
2015
G & G Lab notesG & G Lab notesVery large type 1b natural diamond ( yellow)Gems & Gemology Lab notes, Vol. 51, 4, winter pp. 430-431.TechnologyType 1b diamond
DS201903-0550
2019
G.Wang, D., Vervoort, J.D., Fisher, C.M., Cao, H. Li, G.Integrated garnet and zircon - titanate geochronology constrains the evolution of ultra high pressure terranes: an example from the Sulu orogen.Journal of Metamorphic Geology, in press availableChinaUHP

Abstract: Dating ultrahigh-pressure (UHP) metamorphic rocks provides important timing constraints on deep subduction zone processes. Eclogites, deeply subducted rocks now exposed at the surface, undergo a wide range of metamorphic conditions (i.e., deep subduction and exhumation) and their mineralogy can preserve a detailed record of chronologic information of these dynamic processes. Here we present an approach that integrates multiple radiogenic isotope systems in the same sample to provide a more complete timeline for the subduction-collision-exhumation processes, based on eclogites from the Dabie-Sulu orogenic belt in eastern China, one of the largest ultrahigh-pressure (UHP) terranes on Earth. In this study, we integrate garnet Lu-Hf and Sm-Nd ages with zircon and titanite U-Pb ages for three eclogite samples from the Sulu UHP terrane. We combine this age information with Zr-in-rutile temperature estimates, and relate these multiple chronometers to different P-T conditions. Two types of rutile, one present as inclusions in garnet and the other in the matrix, record the temperatures of UHP conditions and a hotter stage, subsequent to the peak pressure (“hot exhumation”), respectively. Garnet Lu-Hf ages (c. 238 to 235 Ma) record the initial prograde growth of garnet, while coupled Sm-Nd ages (c. 219 to 213 Ma) reflect cooling following hot exhumation. The maximum duration of UHP conditions is constrained by the age difference of these two systems in garnet (c. 235 to 220 Ma). Complementary zircon and titanite U-Pb ages of c. 235 - 230 Ma and c. 216 - 206 Ma provide further constraints on the timing of prograde metamorphism and the "cold exhumation", respectively. We demonstrate that timing of various metamorphic stages can thus be determined by employing complementary chronometers from the same samples. These age results, combined with published data from adjacent areas, show lateral diachroneity in the Dabie-Sulu orogeny. Three sub-blocks are thus defined by progressively younger garnet ages: western Dabie (243 - 238 Ma), eastern Dabie-northern Sulu (238 - 235 Ma,) and southern Sulu terranes (225 - 220 Ma), which possibly correlate to different crustal slices in the recently proposed subduction channel model. These observed lateral chronologic variations in a large UHP terrane can possibly be extended to other suture zones.
DS202002-0172
2019
G.Czas, J., Pearson, G., Stachel, T., Kjarsgaard, B., Read, G.H. J. Pearson, G., Stachel, T., KjaA Paleoproterozoic diamond bearing lithospheric mantle root beneath the Archean Sask craton, Canada.Lithos, DOI:10.1016/ j.lithos.2019.105301Canada, Saskatchewandiamond genesis
DS1982-0214
1982
G.R. Dale and Associates, Anthion Pty. Ltd.G.R. Dale and Associates, Anthion Pty. Ltd.El 2572 and El 2579 Nt Progress Report, Diamond Exploration1981-1982.Northern Territory Geological Survey Open File Report, No. CR 82/345, 6P.Australia, Northern TerritoryProspecting, Geochemistry, Victoria River Basin
DS1986-0259
1986
Gaal, G.Gaal, G.2200 million years of crustal evolution: the Baltic ShieldBulletin. Geological Survey Finland, Vol. 58, pt. 1, pp. 149-68.Finland, Baltic StatesTectonics
DS1987-0232
1987
Gaal, G.Gaal, G.An outline of the Precambrian evolution of the Baltic ShieldPrecambrian Research, Vol. 35, pp. 15-52.Baltic ShieldTectonics - Saamian Orogeny
DS1991-0522
1991
Gaal, G.Gaal, G., Merriam, D.F.Computer applications in resouce estimation prediction and assessment or metals and petroleuM.Pergamon Press, 455p. approx. $ 125.00 United StatesGlobalComputer applications, Book -ad
DS1992-0504
1992
Gaal, G.Gaal, G.Global Proterozoic tectonic cycles and Early Proterozoic metallogeny #1South African Journal of Geology, Vol. 95, No. 3-4, pp. 80-87PangeaPlate tectonics, Metallogeny, Supercontinent
DS1992-0505
1992
Gaal, G.Gaal, G.Global Proterozoic tectonic cycles and Early Proterozoic metallogeny #2South African Journal of Geology, August pp. 79-87South AfricaTectonics, Metallogeny
DS1975-0512
1977
Gaal, R.A.P.Gaal, R.A.P.The Diamond Dictionary 1977Gemological Institute of America, Santa Monica, CA, 342P. 2ND. EDITION.GlobalKimberlite, Kimberley, Janlib, Diamond
DS1995-0537
1995
GababotseField, M., Gibson, J.G., Wilkes, T.A., Gababotse, KhujweThe geology of the Orapa A/K1 kimberlite, Botswana: further insight into the emplacement of kimb. pipes.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 155-57.BotswanaKimberlite genesis, Deposit -Orapa A/K1
DS200812-0374
2008
Gababotse, J.Gababotse, J.Jwaneng mine - the richest diamond deposit.GSSA-SEG Meeting Held July, Johannesburg, 27 Power point slidesAfrica, BotswanaDeposit - Jwaneng
DS201710-2211
2017
Gababotse, J.Armstrong, J.P., Gababotse, J.Karowe diamond mine.11th International Kimberlite Field Trip Guide, Sept. 19p. PdfAfrica, Botswanadeposit - Karowe
DS201708-1642
2017
Gabanakgosi, K.Gabanakgosi, K.Slope stability challenges and solutions for mining kimberlite resources hosted in structurally complex country rock: dip slope mining at Jwaneng mine, Botswana.11th. International Kimberlite Conference, OralAfrica, Botswanadeposit - Jwaneng
DS201712-2681
2018
Gabanakgosi, K.Creus, P.K., Basson, I.J., Stoch, B., Mogorosi, O., Gabanakgosi, K., Ramsden, F., Gaegopolwe, P.Structural analysis and implicit 3D modelling of Jwaneng mine: insights into deformation of the Transvaal Supergroup in SE Botswana.Journal of African Earth Sciences, Vol. 137, pp. 9-21.Africa, Botswanadeposit - Jwaneng

Abstract: Country rock at Jwaneng Diamond Mine provides a rare insight into the deformational history of the Transvaal Supergroup in southern Botswana. The ca. 235 Ma kimberlite diatremes intruded into late Archaean to Early Proterozoic, mixed, siliciclastic-carbonate sediments, that were subjected to at least three deformational events. The first deformational event (D1), caused by NW-SE directed compression, is responsible for NE-trending, open folds (F1) with associated diverging, fanning, axial planar cleavage. The second deformational event (D2) is probably progressive, involving a clockwise rotation of the principal stress to NE-SW trends. Early D2, which was N-S directed, involved left-lateral, oblique shearing along cleavage planes that developed around F1 folds, along with the development of antithetic structures. Progressive clockwise rotation of far-field forces saw the development of NW-trending folds (F2) and its associated, weak, axial planar cleavage. D3 is an extensional event in which normal faulting, along pre-existing cleavage planes, created a series of rhomboid-shaped, fault-bounded blocks. Normal faults, which bound these blocks, are the dominant structures at Jwaneng Mine. Combined with block rotation and NW-dipping bedding, a horst-like structure on the northwestern limb of a broad, gentle, NE-trending anticline is indicated. The early compressional and subsequent extensional events are consistent throughout the Jwaneng-Ramotswa-Lobatse-Thabazimbi area, suggesting that a large area records the same fault geometry and, consequently, deformational history. It is proposed that Jwaneng Mine is at or near the northernmost limit of the initial, northwards-directed compressional event.
DS201811-2563
2018
Gabanakgosi, K.Creus, P.K., Basson, I.J., Stoch, B., Mogorosi, O., Gabanakgosi, K., Ramsden, F., Gaegopolwe, P.Structural analysis and implicit 3D modelling of Jwaneng mine: insights into deformation of the Transvaal Supergroup in SE Botswana.Journal of African Earth Sciences, Vol. 137, pp. 9-21.Africa, Botswanadeposit - Jwaneng

Abstract: Country rock at Jwaneng Diamond Mine provides a rare insight into the deformational history of the Transvaal Supergroup in southern Botswana. The ca. 235 Ma kimberlite diatremes intruded into late Archaean to Early Proterozoic, mixed, siliciclastic-carbonate sediments, that were subjected to at least three deformational events. The first deformational event (D1), caused by NW-SE directed compression, is responsible for NE-trending, open folds (F1) with associated diverging, fanning, axial planar cleavage. The second deformational event (D2) is probably progressive, involving a clockwise rotation of the principal stress to NE-SW trends. Early D2, which was N-S directed, involved left-lateral, oblique shearing along cleavage planes that developed around F1 folds, along with the development of antithetic structures. Progressive clockwise rotation of far-field forces saw the development of NW-trending folds (F2) and its associated, weak, axial planar cleavage. D3 is an extensional event in which normal faulting, along pre-existing cleavage planes, created a series of rhomboid-shaped, fault-bounded blocks. Normal faults, which bound these blocks, are the dominant structures at Jwaneng Mine. Combined with block rotation and NW-dipping bedding, a horst-like structure on the northwestern limb of a broad, gentle, NE-trending anticline is indicated. The early compressional and subsequent extensional events are consistent throughout the Jwaneng-Ramotswa-Lobatse-Thabazimbi area, suggesting that a large area records the same fault geometry and, consequently, deformational history. It is proposed that Jwaneng Mine is at or near the northernmost limit of the initial, northwards-directed compressional event.
DS1988-0040
1988
Gabert, G.Bardinet, C., Gabert, G., Monget, J-M, Zheng YuApplication of multisatellite dat a to thematic mapping #2Geol. Jahrb, Vol. 67, Sect. B., 74p. coloured mapsTanzaniaRemote Sensing, Tectonics
DS1988-0041
1988
Gabert, G.Bardinet, C., Gabert, G., Monget, J-M., Zheng YuApplication of multisatellite dat a to thematic mapping #1Geol. Jahrb, Heft 67, sect. B., 74p. maps approx. 25.00 Database # 1TanzaniaRemote sensing, Structure
DS2002-0493
2002
Gabirelsen, R.H.Gabirelsen, R.H., Braathen, A., Dehls, J., Roberts, D.Tectonic lineaments of NorwayNorsk Geologisk Tidsskrift, Vol. 82, No. 3, pp. 153-174.NorwayTectonics
DS1995-0954
1995
Gable, C.Kincaid, C., Ito, G., Gable, C.Laboratory investigation of the interaction of off axis mantle plumes and spreading centresNature, Vol. 376, No. 6543, Aug. 31, pp. 758-761MantleMantle plumes
DS1992-0506
1992
Gable, C.W.Gable, C.W., King, S.D., Weinstein, S.A.Models of convection driven tectonic plates: a comparison of methods andresultsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 273MantleModel -convection tectonic plates, Tectonics
DS1992-1132
1992
Gable, C.W.O'Connell, R.J., Gable, C.W.Some relations between plate motions and mantle convectionEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 272MantleMantle convection, Tectonics
DS1999-0422
1999
Gable, C.W.Lowman, J.P., Gable, C.W.Thermal evolution of the mantle following continental aggregation in three dimensional convection models.Geophysical Research Letters, Vol. 26, No. 17, Sept. 1, pp. 2649-52.MantleConvection - model
DS2001-0702
2001
Gable, C.W.Lowman, J.P., King, S.D., Gable, C.W.The influence of tectonic plates on mantle convection patterns, temperature and heat flow.Geophys. Jour. International, Vol. 146, No. 3, pp. 619-36.MantleTectonics, Geothermometry
DS2002-0853
2002
Gable, C.W.King, S.D., Lowman, J.P., Gable, C.W.Episodic tectonic plate reorganizations driven by mantle convectionEarth and Planetary Science Letters, Vol. 203, 1, pp. 83-91.MantleTectonics - subduction
DS2003-0847
2003
Gable, C.W.Lowman, J.P., King, S.D., Gable, C.W.The role of the heating mode of the mantle in intermittent reorganization of the plateGeophysical Journal International, Vol. 152, No. 2, pp. 455-67.MantleGeophysics - seismics, melting
DS200812-0378
2008
Gable, C.W.Gait, A.D., Lowman, J.P., Gable, C.W.Time dependence in 3 D mantle convection models featuring evolving plates: effect of lower mantle viscosity.Journal of Geophysical Research, Vol. 113, B08409.MantleGeophysics - seismcis
DS200812-0379
2008
Gable, C.W.Gait, A.D., Lowman, J.P., Gable, C.W.Time dependence in 3 D mantle convection models featuring evolving plates: effect of lower mantle viscosity.Journal of Geophysical Research, Vol. 113, B8, B80409.MantleGeophysics - seismics
DS200912-0455
2008
Gable, C.W.Lowman, J.P., Gait, A.D., Gable, C.W., Kukreja, H.Plumes anchored by a high velocity lower mantle in a 3D mantle convection model featuring dynamically evolving plates.Geophysical Research Letters, Vol. 35, 19, Oct. 16, GLO35342MantleHotspots
DS2002-0494
2002
Gabler, H-E.Gabler, H-E.Applications of magnetic sector ICP-MS in geochemistryJournal of Geochemical Exploration, Vol.75, 1-3, May pp. 1-15.GlobalGeochemistry - techniques, review
DS2003-0433
2003
Gaboret, C.Gaboret, C., Forte, A.M., Montagner, J.P.The unique dynamics of the Pacific hemisphere mantle and its signature on seismicEarth and Planetary Science Letters, Vol. 208, 3-4, pp. 219-233.MantleGeophysics - seismics
DS200412-0596
2003
Gaboret, C.Gaboret, C., Forte, A.M., Montagner, J.P.The unique dynamics of the Pacific hemisphere mantle and its signature on seismic anisotropy.Earth and Planetary Science Letters, Vol. 208, 3-4, pp. 219-233.MantleGeophysics - seismics
DS201509-0405
2015
Gaboury, D.Kamenetsky, V.S., Mitchell, R.H., Maas, R., Giuliani, A., Gaboury, D., Zhitova, L.Chlorine in mantle derived carbonatite melts revealed by halite in the St. Honore intrusion ( Quebec, Canada).Geology, Vol. 43, 8, pp. 687-690.Canada, QuebecCarbonatite

Abstract: Mantle-derived carbonatites are igneous rocks dominated by carbonate minerals. Intrusive carbonatites typically contain calcite and, less commonly, dolomite and siderite as the only carbonate minerals. In contrast, lavas erupted by the only active carbonatite volcano on Earth, Oldoinyo Lengai, Tanzania, are enriched in Na-rich carbonate phenocrysts (nyerereite and gregoryite) and Na-K halides in the groundmass. The apparent paradox between the compositions of intrusive and extrusive carbonatites has not been satisfactorily resolved. This study records the fortuitous preservation of halite in the intrusive dolomitic carbonatite of the St.-Honoré carbonatite complex (Québec, Canada), more than 490 m below the present surface. Halite occurs intergrown with, and included in, magmatic minerals typical of intrusive carbonatites; i.e., dolomite, calcite, apatite, rare earth element fluorocarbonates, pyrochlore, fluorite, and phlogopite. Halite is also a major daughter phase of melt inclusions hosted in early magmatic minerals, apatite and pyrochlore. The carbon isotope composition of dolomite (d13C = –5.2‰) and Sr-Nd isotope compositions of individual minerals (87Sr/86Sri = 0.70287 in apatite, to 0.70443 in halite; eNd = +3.2 to +4.0) indicate a mantle origin for the St.-Honoré carbonatite parental melt. More radiogenic Sr compositions of dolomite and dolomite-hosted halite and heavy oxygen isotope composition of dolomite (d18O = +23‰) suggest their formation at some time after magma emplacement by recrystallization of original magmatic components in the presence of ambient fluids. Our observations indicate that water-soluble chloride minerals, common in the modern natrocarbonatite lavas, can be significant but ephemeral components of intrusive carbonatite complexes. We therefore infer that the parental magmas that produce primary carbonatite melts might be enriched in Na and Cl. This conclusion affects existing models for mantle source compositions, melting scenarios, temperature, rheological properties, and crystallization path of carbonatite melts.
DS1989-0048
1989
Gabov, N.F.Avchenko, O.V, Gabov, N.F., Kozyreva, A.Z., Konikov, A.Z., TravinEclogites of North Muiskaya Block- the composition and genesis.(Russian)Izv. Akad. Nauk SSSR, Ser. Geol., (Russian), No. 5, pp. 68-82RussiaEclogites
DS1989-0049
1989
Gabov, N.F.Avchenko, O.V., Gabov, N.F., Kozyreva, I.V., Konikov, A.Z. Travin.Composition and origin of eclogites of the North Muya blockInternational Geology Review, Vol. 31, No. 8, August pp. 792-805RussiaEclogites, North Muya
DS1989-0457
1989
Gabrielse, H.Gabrielse, H., Yorath, C.J.DNAG # 4. The Cordilleran orogen in CanadaGeoscience Canada, Vol. 16, No. 2, June pp. 67-83CordilleraTectonics-orogeny, Overview
DS1991-0523
1991
Gabrielse, H.Gabrielse, H., Yorath, C.J.Geology of the Cordilleran orogen in Canada. Part of DNAG series.Extracted pages from listing in the index under kimberlite and diatremeGeological Survey of Canada, Vol. 4, pp. 460, 461, 464, 465, 494, 495British ColumbiaBrief overview, Diatreme, kimberlite
DS1991-0524
1991
Gabrielse, H.Gabrielse, H., Yorath, C.J.Geology of the Cordilleran Orogen in Canada. DNAG volume seriesGeological Survey of Canada Geology of Canada DNAG series, No. 4, 840p. $ 80.00British Columbia, CordilleraRegional geology, Table of contents
DS201706-1084
2017
Gabuda, S.P.Khlebopros, R.G., Zakhvataev, V.E., Gabuda, S.P., Kozlova, S.G., Slepkov, V.A.Possible mantle phase transitions by the formation of Si02 peroxides: implications for mantle convection.Doklady Earth Sciences, Vol. 473, 2, pp. 416-418.Mantleconvection

Abstract: On the basis of quantum-chemical calculations of the linear to isomeric bent transition of the SiO2 molecule, it is suggested that the bent to linear transition of SiO2 forms can occur in melted mantle minerals of the lower mantle. This may be important for the formation of the peculiarities of mantle convection and origination of plumes.
DS201912-2837
2019
Gacesa, M.Zahnle, K.J., Gacesa, M., Catling, D.C.Strange messenger: a new history of hydrogen on Earth, as told by xenon.Geochimica et Cosmochimica Acta, Vol. 244, pp. 56-85.Mantleconvection

Abstract: Atmospheric xenon is strongly mass fractionated, the result of a process that apparently continued through the Archean and perhaps beyond. Previous models that explain Xe fractionation by hydrodynamic hydrogen escape cannot gracefully explain how Xe escaped when Ar and Kr did not, nor allow Xe to escape in the Archean. Here we show that Xe is the only noble gas that can escape as an ion in a photo-ionized hydrogen wind, possible in the absence of a geomagnetic field or along polar magnetic field lines that open into interplanetary space. To quantify the hypothesis we construct new 1-D models of hydrodynamic diffusion-limited hydrogen escape from highly-irradiated CO2-H2-H atmospheres. The models reveal three minimum requirements for Xe escape: solar EUV irradiation needs to exceed that of the modern Sun; the total hydrogen mixing ratio in the atmosphere needs to exceed 1% (equiv. to CH4); and transport amongst the ions in the lower ionosphere needs to lift the Xe ions to the base of the outflowing hydrogen corona. The long duration of Xe escape implies that, if a constant process, Earth lost the hydrogen from at least one ocean of water, roughly evenly split between the Hadean and the Archean. However, to account for both Xe’s fractionation and also its depletion with respect to Kr and primordial 244Pu, Xe escape must have been limited to small apertures or short episodes, which suggests that Xe escape was restricted to polar windows by a geomagnetic field, or dominated by outbursts of high solar activity, or limited to transient episodes of abundant hydrogen, or a combination of these. Xenon escape stopped when the hydrogen (or methane) mixing ratio became too small, or EUV radiation from the aging Sun became too weak, or charge exchange between Xe+ and O2 rendered Xe neutral. In our model, Xe fractionation attests to an extended history of hydrogen escape and Earth oxidation preceding and ending with the Great Oxidation Event (GOE).
DS1999-0513
1999
Gacia, M.O.Norman, M.D., Gacia, M.O.Primitive magmas and source characteristics of Hawaiian plume: petrology and geochemistry of shield picrites.Earth and Planetary Science Letters, Vol. 169, No. 1-2, Apr. 30, pp. 27-44.HawaiiPicrites, Geochemistry
DS1992-0507
1992
Gaciri, S.J.Gaciri, S.J.Lineament map of Kenya: correlations of lineaments to known geologicaldataTectonophysics, Vol. 209, pp. 139-142. extended abstractEast Africa, KenyaTectonics, Structure, lineaments
DS1995-1332
1995
Gaciri, S.J.Negecu, W.M., Gaciri, S.J.Lithostratigraphy, provenance and facies distribution on Archean cratonic successions in western KenyaJournal of African Earth Sciences, Vol. 21, No. 3, Oct. 1, pp. 359-372KenyaCraton, Stratigraphy
DS201112-0530
2011
Gadas, P.Kmicek, L., Cempirek, J., Havlin, A., Pfichystal, A., Houzar, S., Kmichkova, M., Gadas, P.Mineralogy and petrogenesis of Ba Ti Zr rich peralkaline dyke from Sebkovice : recognition of the most lamproitic Varascan intrusion.Lithos, Vol. 121, 1-4, pp. 74-86.Europe, Czech RepublicLamproite
DS202009-1637
2020
Gadas, P.Krmicek, L., Romer, R.L., Cempirek, J., Gadas, P., Krmickova, S., Glodny, J.Petrographic and Sr-Nd-Pb-Li isotope characteristics of a complex lamproite intrusion from the Saxo-Thuringian zone: a unique example of peralkaline mantle-derived melt differentiation.Lithos, Vol. 374-375, 15p. PdfEurope, Bohemian Massiflamproites

Abstract: Variscan orogenic lamproites in the Bohemian Massif predominantly occur as 1 to 2?m wide and petrographically uniform dykes along the eastern borders of the Moldanubian and Saxo-Thuringian zones. Variscan orogenic lamproites were derived by preferential melting of subduction-related olivine-free metasomatic vein assemblages stabilised in the lithospheric mantle. These lamproitic melts may subsequently undergo extensive differentiation. In this study, we present the first combined petrographic and Sr-Nd-Pb-Li isotope characteristics of a complex lamproite exposed at ca 100?m long profile near Horní Rokytnice (Czech Republic) in the Saxo-Thuringian Zone. This lamproite is characterised by the primary mineral assemblage of K-amphibole + K-feldspar ± aegirine and quartz that petrographically varies from relatively primitive (fine-grained, mafic) to more differentiated (medium- to coarse-grained, felsic) pegmatitic lamproite domains. These domains may represent the product of crystallisation of immiscible liquids that had separated from the mafic melt. The primitive lamproite zone is characterised by the typomorphic minerals - baotite, benitoite, and henrymeyerite. The more differentiated pegmatitic domains are free of aegirine and show replacement of primary red-luminescent (Fe3+-rich) K-feldspar by blue-luminescent (Fe-poor) K-feldspar. Residual fluids rich in Ca, Ti, and HFSE in combination with the decreasing peralkalinity of the lamproite system resulted in the local formation of secondary zircon, titanite and quartz at the expense of the primary Ti-Ba-Zr-K lamproitic mineral assemblages. Lamproites from the Moldanubian and Saxo-Thuringian zones fall on separate mixing trends in the 87Sr/86Sr(t) - eNd(t) diagram, which indicates that the mantle beneath these two zones had been metasomatised by different crustal material. The scatter in the peralkalinity index vs. d7Li diagram indicates that the Li isotope composition is not controlled by mixing of two end members metasome and ambient depleted mantle alone, but may also be affected by late-stage magmatic and hydrothermal processes. The compositionally zoned Horní Rokytnice dyke is special as the petrographically different types show a variation of about 4 d-units in d7Li due to dyke-internal processes, such as fractionation, which increases d7Li in late-stage lamproitic melts, and post-emplacement interaction with fluids that reduced d7Li in samples that have lost Li. Post-emplacement alteration also led to the disturbance in the Pb isotope systematics of the differentiated orogenic lamproite as indicated by variable over-correction of in situ radiogenic Pb ingrowth.
DS201806-1239
2018
Gadre, S.R.Patwardhan, B., Nagarkar, S., Gadre, S.R., Lakhotia, S.C., Katoch, V.M., Moher, D.A critical analysis of the 'UGC' approved list of journals.Current Science, Vol. 114, 6, Mar. 25, pp. 1299-1303.Indialegal

Abstract: Scholarly journals play an important role in maintaining the quality and integrity of research by what they publish. Unethical practices in publishing are leading to an increased number of predatory, dubious and low-quality journals worldwide. It has been reported that the percentage of research articles published in predatory journals is high in India. The University Grants Commission (UGC), New Delhi has published an 'approved list of journals', which has been criticized due to inclusion of many substandard journals. We have developed a protocol with objective criteria for identifying journals that do not follow good publication practices. We studied 1336 journals randomly selected from 5699 in the university source component of the 'UGC-approved list'. We analysed 1009 journals after excluding 327 indexed in Scopus/Web of Science. About 34.5% of the 1009 journals were disqualified under the basic criteria because of incorrect or non-availability of essential information such as address, website details and names of editors; another 52.3% of them provided false information such as incorrect ISSN, false claims about impact factor, claimed indexing in dubious indexing databases or had poor credentials of editors. Our results suggest that over 88% of the non-indexed journals in the university source component of the UGC-approved list, included on the basis of suggestions from different universities, could be of low quality. In view of these results, the current UGC-approved list of journals needs serious reconsideration. New regulations to curtail unethical practices in scientific publishing along with organization of awareness programmes about publication ethics at Indian universities and research institutes are urgently needed.
DS200912-0622
2008
Gaede, H.Regenauer-Lieb, K., Sommer, H., Gaede, H., Gaede, O.Weertman cracks and the fast extraction of diamonds from the Earth's mantle.American Geological Union, Fall meeting Dec. 15-19, Eos Trans. Vol. 89, no. 53, meeting supplement, 1p. abstractAfrica, BotswanaDeposit - Jwaneng
DS200912-0622
2008
Gaede, O.Regenauer-Lieb, K., Sommer, H., Gaede, H., Gaede, O.Weertman cracks and the fast extraction of diamonds from the Earth's mantle.American Geological Union, Fall meeting Dec. 15-19, Eos Trans. Vol. 89, no. 53, meeting supplement, 1p. abstractAfrica, BotswanaDeposit - Jwaneng
DS200912-0715
2009
Gaede, O.Sommer, H., Regenauer-Lieb, K., Gaede, O.Weertman cracks and the near sonic extraction of diamonds from the Earth's mantle.Goldschmidt Conference 2009, p. A1249 Abstract.Africa, BotswanaDeposit - Jwaneng
DS201112-0986
2011
Gaede, O.Sommer, H., Regenauer-Lieb, K., Gaede, O., Jung, H., Gasharova, B.WEERTMAN cracks: a possible mechanism for near sonic speed diamond extraction from the Earth's mantle.Goldschmidt Conference 2011, abstract p.1908.MantleTransport for diamond bearing kimberlite melts
DS201712-2681
2018
Gaegopolwe, P.Creus, P.K., Basson, I.J., Stoch, B., Mogorosi, O., Gabanakgosi, K., Ramsden, F., Gaegopolwe, P.Structural analysis and implicit 3D modelling of Jwaneng mine: insights into deformation of the Transvaal Supergroup in SE Botswana.Journal of African Earth Sciences, Vol. 137, pp. 9-21.Africa, Botswanadeposit - Jwaneng

Abstract: Country rock at Jwaneng Diamond Mine provides a rare insight into the deformational history of the Transvaal Supergroup in southern Botswana. The ca. 235 Ma kimberlite diatremes intruded into late Archaean to Early Proterozoic, mixed, siliciclastic-carbonate sediments, that were subjected to at least three deformational events. The first deformational event (D1), caused by NW-SE directed compression, is responsible for NE-trending, open folds (F1) with associated diverging, fanning, axial planar cleavage. The second deformational event (D2) is probably progressive, involving a clockwise rotation of the principal stress to NE-SW trends. Early D2, which was N-S directed, involved left-lateral, oblique shearing along cleavage planes that developed around F1 folds, along with the development of antithetic structures. Progressive clockwise rotation of far-field forces saw the development of NW-trending folds (F2) and its associated, weak, axial planar cleavage. D3 is an extensional event in which normal faulting, along pre-existing cleavage planes, created a series of rhomboid-shaped, fault-bounded blocks. Normal faults, which bound these blocks, are the dominant structures at Jwaneng Mine. Combined with block rotation and NW-dipping bedding, a horst-like structure on the northwestern limb of a broad, gentle, NE-trending anticline is indicated. The early compressional and subsequent extensional events are consistent throughout the Jwaneng-Ramotswa-Lobatse-Thabazimbi area, suggesting that a large area records the same fault geometry and, consequently, deformational history. It is proposed that Jwaneng Mine is at or near the northernmost limit of the initial, northwards-directed compressional event.
DS201811-2563
2018
Gaegopolwe, P.Creus, P.K., Basson, I.J., Stoch, B., Mogorosi, O., Gabanakgosi, K., Ramsden, F., Gaegopolwe, P.Structural analysis and implicit 3D modelling of Jwaneng mine: insights into deformation of the Transvaal Supergroup in SE Botswana.Journal of African Earth Sciences, Vol. 137, pp. 9-21.Africa, Botswanadeposit - Jwaneng

Abstract: Country rock at Jwaneng Diamond Mine provides a rare insight into the deformational history of the Transvaal Supergroup in southern Botswana. The ca. 235 Ma kimberlite diatremes intruded into late Archaean to Early Proterozoic, mixed, siliciclastic-carbonate sediments, that were subjected to at least three deformational events. The first deformational event (D1), caused by NW-SE directed compression, is responsible for NE-trending, open folds (F1) with associated diverging, fanning, axial planar cleavage. The second deformational event (D2) is probably progressive, involving a clockwise rotation of the principal stress to NE-SW trends. Early D2, which was N-S directed, involved left-lateral, oblique shearing along cleavage planes that developed around F1 folds, along with the development of antithetic structures. Progressive clockwise rotation of far-field forces saw the development of NW-trending folds (F2) and its associated, weak, axial planar cleavage. D3 is an extensional event in which normal faulting, along pre-existing cleavage planes, created a series of rhomboid-shaped, fault-bounded blocks. Normal faults, which bound these blocks, are the dominant structures at Jwaneng Mine. Combined with block rotation and NW-dipping bedding, a horst-like structure on the northwestern limb of a broad, gentle, NE-trending anticline is indicated. The early compressional and subsequent extensional events are consistent throughout the Jwaneng-Ramotswa-Lobatse-Thabazimbi area, suggesting that a large area records the same fault geometry and, consequently, deformational history. It is proposed that Jwaneng Mine is at or near the northernmost limit of the initial, northwards-directed compressional event.
DS200812-0280
2008
Gaertner, M.Delechat, C., Gaertner, M.Exchange rate assessment in a resource - dependent economy: the case of Botswana.IMF Working Papers, April 1, no. 8083, 200, pp. 1-29. Avail from ingentaAfrica, BotswanaEconomics
DS1993-0475
1993
Gaeta, M.Gaeta, M., Trigil, R.Ultramafic xenoliths bearing on the origin of central Italy potassicmagmatismTerra Abstracts, IAGOD International Symposium on mineralization related to mafic, Vol. 5, No. 3, abstract supplement p. 15ItalyXenoliths, Potassic magma
DS201312-0583
2013
Gaeta, 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
DS200612-0542
2006
Gaetani, G.Hart, S., Gaetani, G.Mantle lead paradoxes: the sulphide solution.Contributions to Mineralogy and Petrology, Vol. 152, 3, pp. 295-308.MantleGeochemistry
DS201412-0258
2014
Gaetani, G.Gaetani, G., O'Leary, J., Koga, K., Hauri, E., Rose-Koga, E., Monteleone, B.Hydration of mantle olivine under variable water and oxygen fugacity conditions.Contributions to Mineralogy and Petrology, Vol. 167, 2, pp. 1-14.MantleOlivine
DS201607-1346
2016
Gaetani, G.Gaetani, G.The influence of spinel lherzolite partial melting on oxygen fugacity in the oceanic upper mantle.IGC 35th., Session The Deep Earth 1 p. abstractMantleMelting
DS1993-0476
1993
Gaetani, G.A.Gaetani, G.A., Grove, T.L., Bryan, W.B.The influence of water on the petrogenesis of subduction related igneousrocksNature, Vol. 365, No. 6444, September 23, pp. 332-335GlobalSubduction, Igneous rocks, Mantle
DS1994-0561
1994
Gaetani, G.A.Gaetani, G.A., Grove, T.L.Melting in the sub arc mantle: effects of H2O on primary magmas and the spinel to garnet transition.Mineralogical Magazine, Vol. 58A, pp. 301-302. AbstractMantleMagma transitions, Peridotite
DS1998-0459
1998
Gaetani, G.A.Gaetani, G.A., Grove, T.L.The influence of water on melting of mantle peridotiteContributions to Mineralogy and Petrology, Vol. 131, No. 4, May pp. 323-46.MantleMelting, Peridotite
DS1999-0232
1999
Gaetani, G.A.Gaetani, G.A., Grove, T.L.Wetting of mantle olivine by sulfide melt: implications for Re/Os ratios In mantle peridotite and late stage ..Earth and Planetary Science Letters, Vol. 169, No. 1-2, May 30, pp. 147-64.MantleSulphides, peridotite, Georchronology - late stage core formation
DS2000-0308
2000
Gaetani, G.A.Gaetani, G.A., Watson, E.B.Open system behaviour of olivine hosted melt inclusionsEarth and Planetary Science Letters, Vol.183, No.1-2, Nov.30, pp.27-41.MantleMelting - olivine, Mineral chemistry
DS2002-0495
2002
Gaetani, G.A.Gaetani, G.A., Watson, R.B.Modeling and the major element evolution of olivine hosted melt inclusionsChemical Geology, Vol.183, 1-4, pp.25-41.MantleMelt - inclusions, Geochemistry
DS2003-0434
2003
Gaetani, G.A.Gaetani, G.A., Kent, A.J., Grove, T.L., Hutcheon, I.D., Stolper, E.M.Mineral melt partitioning of trace elements during hydrous peridotite partial meltingContributions to Mineralogy and Petrology, Vol. 145, 4, pp. 391-405.MantlePeridotites
DS200412-0597
2004
Gaetani, G.A.Gaetani, G.A.The influence of melt structure on trace element partitioning near the peridotite solidus.Contributions to Mineralogy and Petrology, Vol. 147, 5, pp. 511-527.TechnologyPeridotite, mineralogy
DS200412-0598
2003
Gaetani, G.A.Gaetani, G.A., Kent, A.J., Grove, T.L., Hutcheon, I.D., Stolper, E.M.Mineral melt partitioning of trace elements during hydrous peridotite partial melting.Contributions to Mineralogy and Petrology, Vol. 145, 4, pp. 391-405.MantlePeridotite
DS200412-0731
2003
Gaetani, G.A.Grove, T.L., Elkins-Tanton, L.T., Parman, S.W., Chatterjee, N., Muntener, O., Gaetani, G.A.Fractional crystallization and mantle melting controls on calc-alkaline differentiation trends.Contributions to Mineralogy and Petrology, Vol. 145, 5, pp. 515-533.MantleGeochemistry - alkaline
DS200612-0495
2006
Gaetani, G.A.Green, T.H., Hauri, E.H., Gaetani, G.A., Adam, J.New calculations on water storage in the upper mantle, and implications for mantle melting models.Geochimica et Cosmochimica Acta, Vol. 70, 18, 1, p. 215, abstract only.MantleWater
DS200612-0543
2006
Gaetani, G.A.Hart, S.R., Gaetani, G.A.Mantle Pb paradoxes: the sulfide solution.Contributions to Mineralogy and Petrology, in press availableMantlePetrology - peridotites and lead
DS200612-0548
2006
Gaetani, G.A.Hauri, E.H., Gaetani, G.A., Green, T.H.Partitioning of water during melting of the Earth's upper mantle at H2O undersaturated conditions.Earth and Planetary Science Letters, Vol. 248, 3-4, Aug. 30, pp. 715-734.MantleMelting
DS200812-0375
2008
Gaetani, G.A.Gaetani, G.A., Asimov, P.D., Stolper, E.M.A model for rutile saturation in silicate melts with applications to eclogite partial melting in subduction zones and mantle plumes.Earth and Planetary Science Letters, Vol. 272, 3-4, pp. 720-729.MantleSubduction
DS201312-0106
2013
Gaetani, G.A.Bucholz, C.E., Gaetani, G.A., Behn, M.D., Shimizu, N.Post entrapment modification of volatiles and oxygen fugacity in olivine hosted melt inclusions.Earth and Planetary Science Letters, Vol. 392, pp. 39-49.MantleMelting
DS201606-1088
2016
Gaetani, G.A.Gaetani, G.A.The behavior of Fe3/Efe during partial melting of spinel lherzolite.Geochimica et Cosmochimica Acta, in press availableGeothermometry

Abstract: The use of wet chemistry and X-ray absorption near edge structure (XANES) spectroscopy to determine the oxidation state of Fe in submarine glasses and olivine-hosted melt inclusions has provided important new insights into the global systematics of Fe3+/?Fe in mid-ocean ridge basalts (MORB) [1, 2]. Because MORB are aggregates of near-fractional partial melts formed by decompression melting of variably depleted peridotite, it is difficult to judge the extent to which they directly reflect the oxidation state of the oceanic upper mantle. To provide a theoretical framework within which to interpret Fe3+/?Fe in MORB, I have developed a model that describes the behavior of Fe3+/?Fe during spinel lherzolite partial melting in a system closed to oxygen. Modeling is carried out by calculating the Fe3+/?Fe of olivine using the point defect model of [3], and determining Fe3+/?Fe of the bulk peridotite from mineral-mineral partitioning. The inter-mineral Fe3+/Fe2+ exchange coefficients are derived from Mössbauer data on natural spinel peridotites, and are parameterized in terms of oxygen fugacity, temperature, and the Fe content of the olivine. The Fe3+/?Fe of the melt is determined by combining mass-balance with an equation relating the Fe3+/?Fe of the melt to the fugacity of oxygen [4]. Spinel lherzolite partial melting is modeled after [5]. Modeling results indicate that oxygen fugacity does not follow the fayalite-magnetite-quartz (FMQ) buffer during partial melting. For isobaric partial melting, the system becomes reduced relative to FMQ with increasing extent of melting. This results from an increase in the FMQ buffer with increasing temperature, whereas oxygen fugacity in the peridotite remains nearly constant. Conversely, during polybaric partial melting the oxidation state of the residual peridotite increases relative to FMQ. The effective partition coefficient for Fe3+is larger than previously thought, so that a redox couple with S is not required to explain its compatibility during partial melting.
DS201607-1385
2016
Gaetani, G.A.Woodland, A., Gaetani, G.A.Redox reactions as controls on geochemical processes in the crust and mantle.IGC 35th., Session The Deep Earth 1 p. abstractMantleGeochemistry
DS201704-0645
2017
Gaetani, G.A.Sarafian, E., Gaetani, G.A., Hauri, E.H., Sarafian, A.R.Experimental constraints on the damp peridotite solidus and oceanic mantle potential temperature.Science, Vol. 355, 6328, pp. 942-945.MantleGeothermometry

Abstract: Decompression of hot mantle rock upwelling beneath oceanic spreading centers causes it to exceed the melting point (solidus), producing magmas that ascend to form basaltic crust ~6 to 7 kilometers thick. The oceanic upper mantle contains ~50 to 200 micrograms per gram of water (H2O) dissolved in nominally anhydrous minerals, which -relative to its low concentration-has a disproportionate effect on the solidus that has not been quantified experimentally. Here, we present results from an experimental determination of the peridotite solidus containing known amounts of dissolved hydrogen. Our data reveal that the H2O-undersaturated peridotite solidus is hotter than previously thought. Reconciling geophysical observations of the melting regime beneath the East Pacific Rise with our experimental results requires that existing estimates for the oceanic upper mantle potential temperature be adjusted upward by about 60°C.
DS201805-0942
2018
Gaetani, G.A.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.
DS200512-0308
2005
Gaetskii, R.C.Gaetskii, R.C., Dobrolyubov, A.I.The tidal discrete wave mechanism of tectonic movements in the lithosphere.Doklady Earth Sciences, Vol. 400, 1, pp. 35-39.MantleTectonics
DS1991-0274
1991
Gaffey, M.J.Cloutis, E.A., Gaffey, M.J.Pyroxene spectroscopy revisited: spectral-compositional correlations and relationship to geothermometryJournal of Geophysical Research, Vol. 96, No. E5, December 25, pp. 22, 809-22, 826GlobalGeothermometry, Spectroscopy-pyroxene
DS201412-0131
2014
Gaffey, M.J.Cloutis, E.A., Binzel, R.P., Gaffey, M.J.Asteroids: formation and physical properties of asteroids.Elements, Vol. 10, 1, pp. 19-24.TechnologyAsteroids
DS1993-0477
1993
Gaffey. M.J.Gaffey. M.J.Forging an asteroid-meteorite linkScience, Vol. 260, April 9, p. 167-168GlobalMeteorites
DS200612-0420
2006
Gaffney, A.Gaffney, A., Upton, B.Ocean Island basalt like source of kimberlite magmas from West Greenland revealed by high 3 He 4He ratios.Geology, Vol.34, 4, April pp. 273-276.Europe, GreenlandGeochronology, Group I
DS200612-1403
2006
Gaffney, A.Tachibana, Y., Kaneoka, I., Gaffney, A., Upton, B.Ocean Island basalt like source of kimberlite magmas from West Greenland revealed by high 3He 4He ratios.Geology, Vol. 34, 4, pp. 273-276.Europe, GreenlandMagmatism - kimberlite mineral chemistry
DS2002-0496
2002
Gaffney, A.M.Gaffney, A.M.Environemts of crystallization and compositional diversity of Mauna Loa xenolithsJournal of Petrology, Vol.43,6,pp.963-80.GlobalXenoliths - not specific to diamonds
DS200712-0339
2007
Gaffney, A.M.Gaffney, A.M., Blichert-Toft, J., Nelson, B.K., Bizzarro, M., Rosing, M., Albarec, F.Constraints on source forming processes of West Greenland kimberlites inferred from Hf Nd isotope systematics.Geochimica et Cosmochimica Acta, Vol. 71, 11, June 1, pp. 2820-2836.Europe, GreenlandGeochronology
DS200712-0340
2007
Gaffney, A.M.Gaffney, A.M., Blichert-Toft, J., Nelson, B.K., Bizzarro, M., Rosing, M., Albarede, F.Constraints on source forming processes of West Greenland kimberlites inferred from Hf Nd isotope systematics.Geochimica et Cosmochimica Acta, Vol. 71, 11, pp. 2820-2836.Europe, GreenlandDiamond genesis
DS1980-0133
1980
Gafitullina, D.S.Gafitullina, D.S., Khaydarov, A.A.The Nature of Microzoning in Natural DiamondsTsnigri, No. 153, PP. 64-68.RussiaBlank
DS1985-0208
1985
Gafitullina, D.S.Gafitullina, D.S., Solodova, I.P., Khaidarov, A.A.Trace Elements in Diamonds.(russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 284, No. 6, pp. 1464-1466RussiaDiamond Morphology
DS1987-0233
1987
Gafitullina, D.S.Gafitullina, D.S., Solodova, Yu.P., Khaydarov, A.A.Impurities in diamonds with fibrous textureDoklady Academy of Science USSR, Earth Science Section, Vol. 284, No. 5, Publishing July 1987, pp. 163-166RussiaMineralogy
DS1983-0107
1983
Gafiyllina, D.S.Argunov, K.P., Gafiyllina, D.S., Kirikitsa, S.I., Polykanov, Y.V.A.Trace Elements in Small Natural Diamonds.(russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 270, No. 3, pp. 693-695RussiaDiamond Morphology
DS1995-0574
1995
Gaft, M.Gaft, M., Kagan, B., Shoval, S.Laseroluminescent sorting and identification of diamondsProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 172-74.Russia, SiberiaDiamond morphology, Diamond luminescence
DS200412-0599
2004
Gaft, M.Gaft, M., Resifeld, R., Panczer, G.Luminescence spectroscopy of minerals and materials.Springer, 300p. ISBN 3-540-21918-8 $ 130.00TechnologyBook - luminescence
DS201312-0400
2012
Gagan, M.K.Honda, M., Phillips, D., Kendrick, M.A., Gagan, M.K., Taylor, W.R.Noble gas and carbon isotope ratios in Argyle diamonds, western Australia: evidence for a deeply subducted volatile component.Australian Journal of Earth Sciences, Vol. 59, 8, pp. 1135-1142.AustraliaDeposit - Argyle
DS1900-0752
1909
Gagel, C.Gagel, C.Die Nutzbaren Lagerstaetten von Deutsch SuedwestafrikaZeitschr. Berg. Hutt. U Salinenw., Vol. 57, PP. 173-184.Africa, NamibiaDiamond, Mineral Resources
DS1910-0049
1910
Gagel, C.Gagel, C.Ueber die Fortschritte in der Geologischen Erforschung und Der Bergbaulichen Erschliessung der Deutschen Schutzgebiete Seit 1905.Verh. Deutsch. Kolonkongr., PP. 15-32. ALSO: southwest AFRICA WINDHOEK, PP. 19-24.Southwest Africa, NamibiaGeology
DS1920-0033
1920
Gagel, C.Gagel, C.Die Neueren Fortschritte in der Geologischen Erforschung Und der Bergbaulichen Erschliessung der Deutschen Kolonien.Geologische Rundschau, Vol. 1, PP. 280-284.Southwest Africa, NamibiaGeology, Mining
DS201710-2278
2017
Gagen, M.H.Wolfe, A.P., Reyes, A.V., Royer, D.L., Greenwood, D.R., Doria, G., Gagen, M.H., Siver, P.A., Westgate, J.A.Middle Eocene CO2 and climate reconstructed from the sediment fill of a subarctic kimberlite Maar.Geology , Vol. 45, 7, pp. 619-622.Canada, Northwest Territoriesdeposit - Giraffe

Abstract: Eocene paleoclimate reconstructions are rarely accompanied by parallel estimates of CO2 from the same locality, complicating assessment of the equilibrium climate response to elevated CO2. We reconstruct temperature, precipitation, and CO2 from latest middle Eocene (ca. 38 Ma) terrestrial sediments in the posteruptive sediment fill of the Giraffe kimberlite in subarctic Canada. Mutual climatic range and oxygen isotope analyses of botanical fossils reveal a humid-temperate forest ecosystem with mean annual temperatures (MATs) more than 17 °C warmer than present and mean annual precipitation ~4× present. Metasequoia stomatal indices and gas-exchange modeling produce median CO2 concentrations of ~630 and ~430 ppm, respectively, with a combined median estimate of ~490 ppm. Reconstructed MATs are more than 6 °C warmer than those produced by Eocene climate models forced at 560 ppm CO2. Estimates of regional climate sensitivity, expressed as ?MAT per CO2 doubling above preindustrial levels, converge on a value of ~13 °C, underscoring the capacity for exceptional polar amplification of warming and hydrological intensification under modest CO2 concentrations once both fast and slow feedbacks become expressed.
DS1975-1265
1979
GagnonWoussen, G., Gagnon, BONNEAU, Bergeron, DIMROTH, Roy.Lithologie et tectonique des roches Precambriennes et des carbonatites du Saguenay Lac St. Jean.Geological Association of Canada (GAC) Guidebook, Excursion A 3.Quebec, Ungava, LabradorTectonics, Lithology
DS201412-0220
2014
Gagnon, A.Eiler, J.M., Berquist, B., Bourg, I., Cartigny, P., Farquhar, J., Gagnon, A., Guo, W., Halevy, I., Hofman, A., larson, T.E., Levin, N., Schauble, E.A., Stolper, D.Frontiers of stable isotope geoscience.Chemical Geology, Vol. 372, pp. 119-143.TechnologyReview of isotopes
DS1993-0478
1993
Gagnon, G-Y.Gagnon, G-Y., Rainville, J.A kimberlite discovery in the Temiscaminque areaQuebec Exploration Conference summaries held September 15-1th. Val d'Or, pp. 10-12QuebecTemiskaming area
DS200512-0969
2005
Gagnon, J.Shaw, C.S.,Eyzaguirre, J., Fryer, B., Gagnon, J.Regional variations in the mineralogy of metasomatic assemblages in mantle xenoliths with the West Eifel volcanic field, Germany.Journal of Petrology, Vol. 46, 5, May pp. 945-972.Europe, GermanyXenoliths
DS2000-0201
2000
Gahagan, L.M.Dalziel, I.W.D., Mosher, S., Gahagan, L.M.Laurentia Kalahari collision and the assembly of RodiniaJournal of Geology, Vol. 108, pp. 499-513.GlobalCraton, Llano Orogenic belt, Namaqua, Tectonics, suture
DS2002-1575
2002
Gahegan, M.Takatsuka, M., Gahegan, M.GeoVISTA Studio: a codeless visual programming environnment for geoscientific dat a analysis and visualization.Computers and Geosciences, Vol. 28, 10, pp.1131-44.GlobalComputers - programs
DS200612-0173
2006
Gahegan, M.Brodaric, B., Gahegan, M.Representing geoscientific knowledge in cyberinfrastructure: some challenges, approaches and implentatations.In: Sinha, A.K. Geoinformatics: data to knowledge, GSA Special Paper, 397, 397, pp.1-20.TechnologyData - not specific to diamonds
DS200512-0652
2004
Gaherty, D.Lizarralde, D., Gaherty, D., Collins, J.B., Hirth, J.A., Kim, S.D.Spreading rate dependence of melt extraction at mid-ocean ridges from mantle seismic refraction data.Nature, No. 7018, Dec. 9, pp. 744-746.MantleMelting
DS201809-2100
2018
Gaherty, 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.
DS1999-0233
1999
Gaherty, J.B.Gaherty, J.B., Kato, M., Jordan, T.H.Seismological structure of the upper mantle: a regional comparison of seismic layering.Physical Earth and Planetary Interiors, Vol. 110, pp. 21-41.MantleGeophysics - seismics, Discontinuities
DS1999-0234
1999
Gaherty, J.B.Gaherty, J.B., Wang, Y., Weidner, D.J.Testing plausible upper mantle compositions using fine scale models of the410 KM discontinuity.Geophysical Research Letters, Vol. 26, No. 11, June 1, pp. 1641-4.MantleDiscontinuity
DS2001-0336
2001
Gaherty, J.B.Freybouger, M., Gaherty, J.B., Jordan, T.H.Structure of the Kaapvaal craton from surface wavesGeophysical Research Letters, Vol. 28, No. 13, July 1, pp. 2489-92.South AfricaTectonics, Geophysics - seismics
DS200412-0600
2004
Gaherty, J.B.Gaherty, J.B.A surface wave analysis of seismic anisotropy beneath eastern North America.Geophysical Journal International, Vol. 158, 3, pp. 1053-66.United StatesGeophysics - seismics
DS200812-0740
2008
Gaherty, J.B.Mercier, J-P., Bostock, M.G., Audet, P., Gaherty, J.B., Garnero, E.J., Revenaugh, J.The teleseismic signature of fossil subduction: northwestern Canada. (part of Lithoprobe)Journal of Geophysical Research, Vol. 113, B 04308Canada, Northwest TerritoriesGeophysics - seismics
DS200912-0495
2009
Gaherty, J.B.Mercier, J.P., Bostock, M.G., Cassidy, J.F., Dueker, K., Gaherty, J.B., Garnero, E.J., Revenaugh, ZandtBody wave tomography of western Canada.Tectonophysics, Vol. 475, 2, pp. 480-492.Canada, Alberta, British Columbia, Northwest TerritoriesGeophysics - seismics
DS201012-0128
2010
Gaherty, J.B.Courtier, A.M., Gaherty, J.B., Revenaugh, J., Bostock, M.G., Gamero, E.J.Seismic anisotropy associated with continental lithosphere accretion beneath the CANOE array, northwestern Canada.Geology, Vol. 38, 10, pp. 887-890.Canada, Alberta, Northwest TerritoriesGeophysics - seismics
DS201312-0183
2013
Gaherty, J.B.Dalton, C.A., Gaherty, J.B.Seismic anisotropy in the continental crust of northwestern Canada.Geophysical Journal International, Vol. 193, 1, pp. 338-348.Canada, Northwest TerritoriesGeophysics - seismics
DS201811-2612
2018
Gai, S.S.Sun, M., Fu, X., Liu, K.H., Gai, S.S.Absence of thermal influence from the African Superswell and cratonic keels on the mantle transition zone beneath southern Africa: evidence from receiver function imaging.Earth and Planetary Science Letters, Vol. 503, pp. 108-117.Africa, South Africa, Zimbabwegeophysics - seismic

Abstract: The depths of the 410 km (d410) and 660 km (d660) discontinuities beneath southern Africa, which is presumably underlain by the lower-mantle African Superswell, are imaged in 1° radius consecutive circular bins using over 6400 P-to-S receiver functions (RFs) recorded by 130 seismic stations over a 27 yr period. When the IASP91 standard Earth model is utilized for moveout correction and time-depth conversion, a normal mantle transition zone (MTZ) thickness of 246 ± 7 km is observed, suggesting that the Superswell has no discernible effect on mantle transition zone temperature. Based on the negligible disparity of the mean MTZ thicknesses between on (246 ± 6 km) and off (246 ± 8 km) cratonic regions, we conclude that the deep Archean cratonic keels possess limited influence on MTZ thermal structure. The apparently shallower-than-normal MTZ discontinuities and the parallelism between the d410 and d660 are mostly the results of upper mantle high wave speed anomalies probably corresponding to a thick lithosphere with a mean thickness of about 245 km beneath the Kaapvaal and 215 km beneath the Zimbabwe cratons. In contradiction to conclusions from some of the previous studies, the resulting spatial distribution of the stacking amplitudes of the P-to-S converted phases at the discontinuities is inconsistent with the presence of an excessive amount of water in the MTZ and atop the d410.
DS2002-1530
2002
GaiborSpencer, R.M., Montenegro, J.L., Gaibor,Perez,MantillaThe Portovelo Zaruma mining camp: southwest Ecuador: porphyry and epithermal environments.Seg Newsletter, No. 49, April, pp. 1,8-14.EcuadorCopper, gold, Deposit - Portovelo Zaruma, R-Nivel, Muluncay
DS200512-0625
2005
Gaidamako, I.M.Levchenkov, O.A., Gaidamako, I.M., Levskii, L.K., Komarov, Yakovleva, Rizvanova, MakeevU Pb age of zircon from the Mir and 325 Let Yakutii pipes.Doklady Earth Sciences, Vol. 400, 1, pp. 99-101.Russia, YakutiaGeochronology
DS201112-0340
2011
Gaidoes, F.Gaidoes, F., Pattison, D.R.M., De Capitani, C.Toward a quantitative model of metamorphic nucleation and growth.Contributions to Mineralogy and Petrology, Vol. 162, 5, pp.975-1009.MantleContinent accretion
DS201706-1075
2017
Gaiduk, A.V.Gordadze, G.N., Kerimov, V.Yu., Gaiduk, A.V., Giruts, M.V., Lobusev, M.A., Serov, S.G., Kuznetsov, N.B., Romanyuk, T.V.Hydrocarbon biomarkers and diamondoid hydrocarbons from Late Precambrian and Lower Cambrian rocks of the Katanga Saddle ( Siberian Platform).Geochemistry International, Vol. 55, 4, pp. 360-366.Russia, Siberiadiamondoid

Abstract: A broad suite of geological materials were studied a using a handheld laser-induced breakdown spectroscopy (LIBS) instrument. Because LIBS is simultaneously sensitive to all elements, the full broadband emission spectrum recorded from a single laser shot provides a ‘chemical fingerprint’ of any material - solid, liquid or gas. The distinguishing chemical characteristics of the samples analysed were identified through principal component analysis (PCA), which demonstrates how this technique for statistical analysis can be used to identify spectral differences between similar sample types based on minor and trace constituents. Partial least squares discriminant analysis (PLSDA) was used to distinguish and classify the materials, with excellent discrimination achieved for all sample types. This study illustrates through four selected examples involving carbonate minerals and rocks, the oxide mineral pair columbite-tantalite, the silicate mineral garnet and native gold how portable, handheld LIBS analysers can be used as a tool for real-time chemical analysis under simulated field conditions for element or mineral identification plus such applications as stratigraphic correlation, provenance determination and natural resources exploration.
DS1989-0458
1989
Gaiduk, V.V.Gaiduk, V.V., Shamshina, E.A.First find of pyropes in lower carboniferous conglomerates of the Ygyattinskii basin (Siberian platform)Soviet Geology and Geophysics, Vol. 30, No. 9, pp. 118-120RussiaPyropes, Mineralogy
DS1987-0020
1987
Gaidukova, V.S.Bagdasarov, Yu.M., Gaidukova, V.S.Structure and origin of magnetite from rocks on their on ore complex and carbonatites of northernSiberia.(Russian)Zap. Vses. Mineral. O-Va, (Russian), Vol. 116, No. 6, pp. 645-658RussiaCarbonatite
DS201903-0542
2019
Gailland, O.Schmiedel, T., Gailland, O., Haug, O.T., Dumazer, G., Breikreuz, C.Coulomb failure of Earth's brittle crust controls growth, emplacement and shapes of igneous sills, saucer-shaped sills and laccoliths.Earth and Planetary Science Letters, Vol. 510, pp. 161-172.MantleMagmatism

Abstract: Tabular intrusions are common features in the Earth's brittle crust. They exhibit a broad variety of shapes, ranging from thin sheet intrusions (sills, saucer-shaped sills, cone sheets), to more massive intrusions (domed and punched laccoliths, stocks). Such a diversity of intrusion shapes reflects different emplacement mechanisms caused by contrasting host rock and magma rheologies. Most current models of tabular intrusion emplacement assume that the host rock behaves purely elastically, whereas numerous observations show that shear failure plays a major role. In this study, we investigate the effects of the host rock's Coulomb properties on magma emplacement by integrating (1) laboratory models using dry Coulomb granular model hosts of variable strength (cohesion) and (2) limit analysis numerical models. Our results show that both sheet and massive tabular intrusions initiate as a sill, which triggers shear failure of its overburden along an inclined shear damage zone at a critical sill radius, which depends on the emplacement depth and the overburden's cohesion. Two scenarios are then possible: (1) if the cohesion of the overburden is significant, opening of a planar fracture along the precursory weakened shear damage zones to accommodate magma flow, leads to the formation of inclined sheets, or (2) if the cohesion of the overburden is negligible, the sill inflates and lifts up the overburden, which is dissected by several faults that control the growth of a massive intrusion. Finally, we derive a theoretical scaling that predicts the thickness-to-radius aspect ratios of the laboratory sheet intrusions. This theoretical prediction shows how sheet intrusion morphologies are controlled by a mechanical equilibrium between the flowing viscous magma and Coulomb shear failure of the overburden. Our study suggests that the emplacement of sheet and massive tabular intrusions are parts of the same mechanical regime, in which the Coulomb behavior of the Earth's brittle crust plays an essential role.
DS201904-0757
2019
Gaillard, C.Malavergegne, V., Bureau, H., Raepsaet, C., Gaillard, C., Poncet, F., Surble, M., Sifre, S., Shcheka, D., Fourdrin, S., Deldicque, C., Khodja, D., HichamExperimental constraints on the fate of H and C during planetary core-mantle differentiation. Implications for the Earth.Icarus - New York, Vol. 321, 1, pp. 473-485.Mantlecarbon

Abstract: Hydrogen (H) and carbon (C) have probably been delivered to the Earth mainly during accretion processes at High Temperature (HT) and High Pressure (HP) and at variable redox conditions. We performed HP (1-15?GPa) and HT (1600-2300°C) experiments, combined with state-of-the-art analytical techniques to better understand the behavior of H and C during planetary differentiation processes. We show that increasing pressure makes H slightly siderophile and slightly decreases the highly siderophile nature of C. This implies that the capacity of a growing core to retain significant amounts of H or C is mainly controlled by the size of the planet: small planetary bodies may retain C in their cores while H may have rather been lost in space; larger bodies may store both H and C in their cores. During the Earth's differentiation, both C and H might be sequestrated in the core. However, the H content of the core would remain one or two orders of magnitude lower than that of C since the (H/C)core ratio might range between 0.04 and 0.27.
DS201909-2040
2019
Gaillard, E.Gaillard, E., Nabyl, Z., Tuduri, J., Di Carlo, I., Melleton, J., Bailly, L.The effects of F, Cl, P and H2O on the immiscibility and rare metals partitioning between carbonate and phonolite melts.Goldschmidt2019, 1p. AbstractGlobalcarbonatite - REE

Abstract: Carbonatite and alkaline magma constitute one of the principal resources of rare metals (REE, Nb, Ti, Zr). Carbonatite rare metals enrichment is mainly considered as the result of hydrothermal or supergen processes. However, the magmatic processes linked to carbonatites genesis and differentiation are still debated and whether these processes can significantly impact on the rare metal concentrations remains unclear. Experimental studies have shown that immiscibility processes between carbonate and silicate melts can lead to both REE enrichments and depletions in carbonatites. Anionic species (F, Cl, P or S) and water may impact both melt compositions and expand the immiscibility gap. Morever, anionic species are assumed to play an important role in REE behaviour in carbonate melts [1]. Indeed, halogens may occur in carbonatites as immiscible salt melts in melt inclusions [2] and primary REE- fluoride minerals have been identified as magmatic phases in carbonatites. Such occurrences thus question on the role of salt (carbonate, phosphate, fluoride and chloride) melts in REE and other rare metals partitioning. F, Cl, P and also H2O may all significantly increase the window of primary REE enrichment in carbonatites. Here we present high pressure and high temperature experiments made in piston-cylinder (850 to 1050°C, 8kb) simulating the immiscibility between carbonate and differentiated alkaline melts. We added F, Cl, P and H2O in order to assess the effect of salts and water on the immiscibility gap and on the rare metals partitoning between carbonatite and evolved silicate melts. The partitioning data are analysed using LA-ICP-MS, nano-SIMS, FTIR and RAMAN. The characterization of rare metal partition coefficients allow to determine the relative importance of F, Cl, P and H2O on carbonatites rare metal enrichments at evolved magmatic stage.
DS200612-0327
2006
Gaillard, F.Demouchy, S., Jacobsen, S.D., Gaillard, F., Stern, C.R.Rapid magma ascent recorded by water diffusion profiles in mantle olivine.Geology, Vol. 34, 6, June pp. 429-432.Mantle, South America, ChileMagmatism, xenoliths - not specific to diamonds
DS200712-0064
2006
Gaillard, F.Behrens, H., Gaillard, F.Geochemical aspects of melts: volatiles and redox behaviour.Elements, Vol. 2, 5, October pp. 275-280.TechnologyGeochemistry
DS200912-0238
2008
Gaillard, F.Gaillard, F.Carbonatite melts and electrical conductivity in the athenosphere: the electrical conductivity of molten carbonates is higher than that of silicate minerals;Science, Vol. 322, no. 5906, Nov. 28, pp. 1363-1364.MantleCarbonatite
DS201012-0592
2010
Gaillard, F.Pommier, A., Gaillard, F., Pichavant, M.Time dependent changes of the electrical conductivity of basaltic melts with redox state.Geochimica et Cosmochimica Acta, Vol. 74, 5, pp. 1653-1671.MantleRedox
DS201412-0818
2014
Gaillard, F.Shiryeav, A.A., Gaillard, F.Local redux buffering by carbon at low pressures and the formation of moissanite natural SiC.European Journal of Mineralogy, Vol. 26, 1, pp. 53-59.TechnologyMoissanite
DS201510-1786
2015
Gaillard, F.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.
DS201603-0402
2016
Gaillard, F.Moussallam, Y., Florian, P., Corradini, D., Morizet, Y., Sator, N., Vuilleumier, R., Guillot, B., Iacono-Marziano, G., Schmidt, B.C., Gaillard, F.The molecular structure of melts along the carbonatite-kimberlite-basalt compositional joint: CO (sub 2) and polymerisation.Earth and Planetary Science Letters, Vol. 434, pp. 129-140.TechnologyPetrology - experimental

Abstract: Transitional melts, intermediate in composition between silicate and carbonate melts, form by low degree partial melting of mantle peridotite and might be the most abundant type of melt in the asthenosphere. Their role in the transport of volatile elements and in metasomatic processes at the planetary scale might be significant yet they have remained largely unstudied. Their molecular structure has remained elusive in part because these melts are difficult to quench to glass. Here we use FTIR, Raman, 13C and 29Si NMR spectroscopy together with First Principle Molecular Dynamic (FPMD) simulations to investigate the molecular structure of transitional melts and in particular to assess the effect of CO2 on their structure. We found that carbon in these glasses forms free ionic carbonate groups attracting cations away from their usual ‘depolymerising’ role in breaking up the covalent silicate network. Solution of CO2 in these melts strongly modifies their structure resulting in a significant polymerisation of the aluminosilicate network with a decrease in NBO/Si of about 0.2 for every 5 mol% CO2 dissolved. This polymerisation effect is expected to influence the physical and transport properties of transitional melts. An increase in viscosity is expected with increasing CO2 content, potentially leading to melt ponding at certain levels in the mantle such as at the lithosphere-asthenosphere boundary. Conversely an ascending and degassing transitional melt such as a kimberlite would become increasingly fluid during ascent hence potentially accelerate. Carbon-rich transitional melts are effectively composed of two sub-networks: a carbonate and a silicate one leading to peculiar physical and transport properties.
DS201603-0403
2015
Gaillard, F.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.
DS201607-1309
2016
Gaillard, F.Moussallam, Y., Morizet, Y., Gaillard, F.H2O-CO2 solubility in low SiO2-melts and the unique mode of kimberlite degassing and emplacement.Earth and Planetary Science Letters, Vol. 447, pp. 151-160.Mantle, Europe, ItalyKimberlite formation, volcanism, melting

Abstract: Kimberlites are the most deep-seated magmas in the mantle and ascend to the surface at an impressive speed, travelling hundreds of kilometres in just hours while carrying a substantial load of xenolithic material, including diamonds. The ascent dynamics of these melts are buoyancy-controlled and certainly driven by outgassing of volatile species, presumably H2O and CO2, summing to concentration level of ca 15 -30 wt.% in kimberlite melts. We provide H2O -CO2 solubility data obtained on quenched glasses that are synthetic analogues of kimberlite melts (SiO2 content ranging from 18 to 28 wt.%). The experiments were conducted in the pressure range 100 to 350 MPa. While the CO2 solubility can reach 20 wt.%, we show that the H2O solubility in these low silica melts is indistinguishable from that found for basalts. Moreover, whereas in typical basalts most of the water exsolves at shallower pressure than the CO2, the opposite relationship is true for the low-SiO2 composition investigated. These data show that kimberlites can rise to depths of the upper crust without suffering significant degassing and must release large quantities of volatiles (>15 wt.%) within the very last few kilometres of ascent. This unconventional degassing path may explain the characteristic pipe, widening-upward from a =2.5 km deep root zone, where kimberlites are mined for diamonds. Furthermore, we show that small changes in melt chemistry and original volatile composition (H2O vs. CO2) provide a single mechanism to explain the variety of morphologies of kimberlite pipes found over the world. The cooling associated to such massive degassing must freeze a large quantity of melt explaining the occurrence of hypabyssal kimberlite. Finally, we provide strong constraints on the primary volatile content of kimberlite, showing that the water content reported for kimberlite magma is mostly reflective of secondary alteration.
DS201612-2277
2016
Gaillard, F.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.
DS201909-2065
2019
Gaillard, F.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 (SREE > 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
Gaillard, F.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
Gaillard, F.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.
DS202010-1862
2020
Gaillard, F.Morizet, Y., Larre, C., Di Carlo, I., Gaillard, F.High S and high CO2 contents in haplokimberlite: an experimental and Raman spectroscopic study.Mineralogy and Petrology, Vol. 114, pp. 363-373. pdfMantlemelting

Abstract: Sulfur is an important element present in natural kimberlites and along with CO2, S can play a role in the kimberlite degassing. We have investigated experimentally the change in S content and CO2 solubility in synthetic kimberlitic melts in response to a range of pressure (0.5 to 2.0 GPa) and temperature (1500 to 1525 °C). Several initial S concentrations were investigated ranging from 0 to 24000 ppm. The dissolved CO2 and S were determined by Raman spectroscopy and Electron Probe Micro-Analyses. Under the investigated oxidizing conditions (?FMQ?+?1), S is dissolved in the glass only as S6+ forming sulfate molecular groups (SO42-). The measured S concentration in the glasses increases from 2900 to 22000 ppm. These results suggest that the experimental conditions were below saturation with respect to S and that the S solubility is higher than 22000 ppm for kimberlitic melts; regardless of the experimental conditions considered here. CO2 is dissolved as CO32- molecular groups. The CO2 solubility ranges from 3.0 to 11.3 wt% between 0.5 and 2.0 GPa. CO2 solubility is not affected by the presence of S; which suggests that SO42- and CO32- clusters have two distinct molecular environments not interacting together. This result implies that both CO2 and S are efficiently transported by kimberlitic melt from the upper mantle towards the atmosphere.
DS1996-0395
1996
Gaillardet, J.Dupre, B., Gaillardet, J., Rousseau, D., Allegre, C.J.Major and trace elements of river borne material: The Congo BasinGeochimica et Cosmochimica Acta, Vol. 60, No. 8, April pp. 1301-1321.Central African RepublicCongo River Basin, Black Rivers, weathering
DS2002-1056
2002
Gaillardet, J.Millot, R., Gaillardet, J., Dupre, B., Allegre, C.J.The global control of silicate weathering rates and the coupling of physical erosion: new insights from riversEarth and Planetary Science Letters, Vol.196, 1-2, Feb.28, pp.83-98.Northwest Territories, Alberta, Manitoba, Ontario, QuebecGeomorphology
DS200412-1313
2004
Gaillardet, J.Millot, R., Allegre, C.J., Gaillardet, J., Roy, S.Lead isotopic systematics of major river sediments: a new estimate of the Pb isotopic composition of the Upper Continental CrustChemical Geology, Vol. 203, 1-2, Jan. 15, pp. 75-90.MantleGeochronology
DS201312-0291
2012
Gaillardet, J.Galvez, M.E., Gaillardet, J.Historical constraints on the origins of the carbon cycle concept.Comptes Rendus Geoscience, Vol. 344, pp. 549-567.MantleCarbon cycle
DS201112-1098
2011
GaillouWalter, M.J., Kohn, Arajuo, Bulanova, Smith, Gaillou, Wang, Steele, ShireyDeep mantle cycling of oceanic crust: evidence from diamonds and their mineral inclusions.Science, Vol. 334, 6052, pp. 51-52.MantleDiamond inclusions
DS200812-0376
2007
Gaillou, E.Gaillou, E., Post, J.E.An examination of the Napoleon diamond necklace.Gems & Gemology Lab Notes, Vol. 43, 4, Winter pp. 352-357.TechnologyType 1a and 11a diamonds
DS201012-0214
2010
Gaillou, E.Gaillou, E., Post, J.E., Bassim, N.D., Zaitsev, A.M., Rose, T., Fries, M.D., Stroud, R.M., Steele, A., Butler, J.E.Spectroscopic and microscopic characterizations of color laminae in natural pink diamonds.Diamond and Related Materials, Vol. 19, 10, pp. 1207-1220.TechnologySpectroscopy
DS201012-0215
2010
Gaillou, E.Gaillou, E., Rost, D., Post, J., Butler, J.Quantifying boron in natural type IIb blue diamonds.Goldschmidt 2010 abstracts, abstractTechnologyDiamond morphology
DS201012-0216
2010
Gaillou, E.Gaillou, E., Wang, W., Post, J.E., King, J.M., Butler, J.E., Collins, A.T., Moses, T.M.The Wittelsbach-Graff and Hope diamonds: not cut from the same rough.Gems & Gemology, Vol. 46, 2, pp. 80-88.TechnologyDiamonds notable
DS201112-0341
2011
Gaillou, E.Gaillou, E., Post, J.E., Butler, J.E.On the pecularities of Australian and Venezuelan pink diamonds: influence of the geologic settings.Goldschmidt Conference 2011, abstract p.882.Australia, South America, VenezuelaArgyle, Santa Elena, high thermal events
DS201212-0096
2012
Gaillou, E.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
DS201212-0225
2012
Gaillou, E.Gaillou, E.,Post, J.E., Rost, D., Butler, J.E.Boron in natural type 11b blue diamonds: chemical and spectroscopic measurements.American Mineralogist, Vol. 97, pp. 1-18.TechnologyBlue diamond
DS201412-0260
2014
Gaillou, E.Gaillou, E., Rossman, G.R.Color in natural diamonds: the beauty of defects.Rocks and Minerals, Jan-Feb. pp. 66-75.TechnologyDiamond - colour
DS201503-0144
2015
Gaillou, E.Gaillou, E., Post, J.E., Byne, K.S., Butler, J.E.Study of the Blue Moon diamond. ( from Cullinan)Gems & Gemology, Vol. 50, 4, winter 2014, 9p.Africa, South AfricaDiamonds notable

Abstract: The Blue Moon diamond, discovered in January 2014 at the historic Cullinan mine in South Africa, is of significance from both trade and scientific perspectives. The 29.62 ct rough yielded a 12.03 ct Fancy Vivid blue, Internally Flawless gem. The authors were provided the opportunity to study this rare diamond at the Smithsonian Institution before it went on exhibit at the Natural History Museum of Los Angeles County. Infrared spectroscopy revealed that the amount of uncompensated boron in the diamond was 0.26 ± 0.04 ppm, consistent with measurements of several large type IIb blue diamonds previously studied. After exposure to short-wave ultraviolet light, the Blue Moon displayed orange-red phosphorescence that remained visible for up to 20 seconds. This observation was surprising, as orange-red phosphorescence is typically associated with diamonds of Indian origin, such as the Hope and the Wittelsbach-Graff. Time-resolved phosphorescence spectra exhibited peaks at 660 and 500 nm, typical for natural type II blue diamonds. As with most natural diamonds, the Blue Moon showed strain-induced birefringence.
DS201605-0897
2016
Gaillou, E.Schoor, M., Boulliard, J.C., Gaillou, E., Duparc, O.H., Esteve, I., Baptiste, B., Rondeau, B., Fritsch, E.Plastic deformation in natural diamonds: rose channels associated to chemical twinning.Diamond and Related Materials, in press available 14p.TechnologyDiamond morphlogy
DS201608-1434
2016
Gaillou, E.Post, J.E., Gaillou, E., Butler, J.E., Byrne, K.S.Investigations into luminescence properties and compositions of colored diamonds.GSA Annual Meeting, Abstract, 1p.TechnologyLuminescence

Abstract: The Smithsonian’s National Gem Collection includes the Hope Diamond and an assortment of other significant fancy-colored diamonds, providing a unique opportunity to conduct detailed and sustained studies on an unprecedented selection of these rare and valuable stones. We present an overview and recent results from our work on pink, blue and chameleon diamonds. Boron causes the blue color of the Hope Diamond and other type IIb diamonds, but scarcity, high value, and the low concentration of B has inhibited B analyses of natural IIb diamonds. We used FTIR and ToF-SIMS to measure concentrations and distributions of B in the Hope and other blue diamonds. ToF-SIMS analyses gave spot B concentrations as high as 8.4 ± 1.1 ppm for the Hope Diamond to less than 0.08 ppm in other blue diamonds and revealed strong zoning of B in some diamonds, which was confirmed by mapping using synchrotron FTIR. Boron is also responsible for the phosphorescence emissions of IIb diamonds, at 660 nm and 500 nm; the emissions are likely caused by donor-acceptor pair recombination processes involving B and other defects. Approximately 50 type I natural pink diamonds were compared using UV-Vis, FTIR, and CL spectroscopies. All stones exhibit pink color zoning, ~1µm thick [111] lamellae, in otherwise colorless diamond. The pink diamonds fall into two groups: 1) those from Argyle in Australia and Santa Elena in Venezuela, and 2) those from other localities. TEM imaging from FIB sections revealed that twinning is the likely mechanism by which plastic deformation is accommodated for the pink diamonds. The deformation creates new centers, including the one responsible for the pink color, which remains unidentified. The differences in the plastic deformation features for the two groups might correlate to the particular geologic conditions under which the diamonds formed. Fluorescence and thermoluminescence experiments on natural chameleon diamonds reveal that an emission band, peaking near 556nm, may be stimulated via a number of different mechanisms. We discuss the implications of our observations for the electronic structure of the 556nm-fluorescing defect center, and the connections to the unidentified color center responsible for chameleon color changes.
DS201610-1900
2016
Gaillou, E.Post, J.E., Gaillou, E., Butler, J.E., Byrne, K.S.Investigations into the luminescence properties and compositions of colored diamonds. ( blue and pink)GSA Annual Meeting, 1/2p. abstractTechnologyColoured diamonds

Abstract: The Smithsonian’s National Gem Collection includes the Hope Diamond and an assortment of other significant fancy-colored diamonds, providing a unique opportunity to conduct detailed and sustained studies on an unprecedented selection of these rare and valuable stones. We present an overview and recent results from our work on pink, blue and chameleon diamonds. Boron causes the blue color of the Hope Diamond and other type IIb diamonds, but scarcity, high value, and the low concentration of B has inhibited B analyses of natural IIb diamonds. We used FTIR and ToF-SIMS to measure concentrations and distributions of B in the Hope and other blue diamonds. ToF-SIMS analyses gave spot B concentrations as high as 8.4 ± 1.1 ppm for the Hope Diamond to less than 0.08 ppm in other blue diamonds and revealed strong zoning of B in some diamonds, which was confirmed by mapping using synchrotron FTIR. Boron is also responsible for the phosphorescence emissions of IIb diamonds, at 660 nm and 500 nm; the emissions are likely caused by donor-acceptor pair recombination processes involving B and other defects. Approximately 50 type I natural pink diamonds were compared using UV-Vis, FTIR, and CL spectroscopies. All stones exhibit pink color zoning, ~1µm thick [111] lamellae, in otherwise colorless diamond. The pink diamonds fall into two groups: 1) those from Argyle in Australia and Santa Elena in Venezuela, and 2) those from other localities. TEM imaging from FIB sections revealed that twinning is the likely mechanism by which plastic deformation is accommodated for the pink diamonds. The deformation creates new centers, including the one responsible for the pink color, which remains unidentified. The differences in the plastic deformation features for the two groups might correlate to the particular geologic conditions under which the diamonds formed. Fluorescence and thermoluminescence experiments on natural chameleon diamonds reveal that an emission band, peaking near 556nm, may be stimulated via a number of different mechanisms. We discuss the implications of our observations for the electronic structure of the 556nm-fluorescing defect center, and the connections to the unidentified color center responsible for chameleon color changes.
DS201703-0442
2017
Gaillou, E.Zubkov, V.I., Solomnikova, A.V., Post, J.E., Gaillou, E., Butler, J.E.Characterization of electronic properties of natural type 11b diamonds.Diamond and Related Materials, Vol. 72, pp. 87-93.TechnologyDiamonds - type 11b

Abstract: Precision admittance spectroscopy measurements were carried out over wide temperature and frequency ranges for a set of natural single crystal type IIb diamond samples. Peaks of conductance spectra vs. temperature and frequency were used to compute the Arrhenius plots, and activation energies were derived from these plots. The capacitance-voltage profiling was used to estimate the majority charge carrier concentration and its distribution into depth of the samples. Apparent activation energies between 315 and 325 meV and the capture cross section of about 10- 13 cm2 were found for samples with uncompensated boron concentrations in the range of 1 to 5 × 1016 cm- 3 (0.06-0.3 ppm). The obtained boron concentrations are in good coincidence with FTIR results for the samples. Also, a reason for the difference between the observed admittance activation energy and the previously reported ionization energy for the acceptor boron in diamond (0.37 eV) is proposed.
DS201705-0827
2017
Gaillou, E.Gaillou, E., Rossman, G.R.On the Beauty of Defects.lithographie.org, No. 19, pp. 40-53.TechnologyBook - diamond colour

Abstract: Extensive study has shown that these inclusions contain mantle-derived fluids (e.g. Navon et al., 1988, Izraeli et al., 2001, 2004 Tomlinson et al., 2009; Logvinova et al., 2011; Zedgenizov et al., 2011; Smith et al., 2012, Smith et al., 2015 Howell et al., 2012b Howell et al., , 2013 Weiss et al., 2013 Weiss et al., , 2015 Rakovan et al., 2014; Smit et al., in press), Here we use the term 'milky' to describe diamonds that contain zones of opalescent to brown or grey opaque appearance (Gaillou and Rossman, 2014). The exact cause of this opacity is yet to be defined, and forms the purpose of this paper.
DS201809-2014
2018
Gaillou, E.Daver, L., Bureau, H., Gaillou, E., Ferraris, C., Bouillard, J-C., Cartigny, P., Pinti, D.L.In situ analysis of inclusions in diamonds from collections.Goldschmidt Conference, 1p. AbstractGlobaldiamond inclusions

Abstract: Diamonds represent one of the few witnesses of our planet interior. They are mainly formed in the first 200 km of the lithospheric mantle, and, more rarely from the transition zone to 700 km deep. Diamonds contain a lot of information about global evolution, however their mode of formation remains poorly understood. Recent studies in high-pressure mineralogy suggest that diamonds precipitate from oxidized metasomatic fluids. The study of inclusions trapped in diamonds may provide precise information on composition, pressure, temperature and redox conditions. The aim of this study is to use the inclusions trapped in diamond as probes of the deep cycling of volatiles (C, H, halogens). Therefore, we investigate inclusions in diamonds with a systematic study of diamonds from collections. We selected 73 diamonds from three museums: National Museum of Natural History, School of Mines and Sorbonne University. The selected diamonds are studied with the help of a large range of in situ methods: RAMAN and FTIR spectrometry and X-Ray Diffraction. These analyses allow us to identify the nature of the different inclusions without damaging the gems. First results indicate silicate minerals inclusions as pyrope garnet, olivine and enstatite pyroxene. This assemblage is typical of peridotitic-type diamonds in the lithosphere.
DS201812-2785
2018
Gaillou, E.Bulanova, G.P., Speich, L. Smith, C.B., Gaillou, E., Koln, S.C., Wibberley, E., Chapman, J.G., Howell, D., Davy, A.T.Argyle deposit: The unique nature of Argyle fancy diamonds: internal structure, paragenesis, and reasons for color.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 169-190.Australia, western Australiadeposit - Argyle
DS201905-1032
2014
Gaillou, E.Gaillou, E., Rossman, G.R.Color in natural diamonds .. The beauty of defects. Note date ***Rocks & Minerals, 12p.Globaldiamond colour

Abstract: In its pure form, diamond is colorless. However, in nature (or even when made in laboratories), diamonds are never composed of 100 percent carbon atoms. Even colorless diamonds will contain some defects: missing carbon atoms or containing trace amounts of nitrogen or hydrogen, for example. When present in certain atomic arrangements and concentrations, most minor components cause absorption of specific wavelengths of light, giving rise to color. The color in diamond is not source specific, even if some mines are known to produce more of certain colors, such as blue diamonds from the Premiere mine in South Africa, or brown and pink diamonds from the Argyle mine in Australia. Virtually every single diamond mine could produce any kind of colored diamond. At auction, record prices for gems are currently held by pink and blue diamonds: for example, $2,155,332 per carat for a 24.78-carat Fancy vivid pink diamond (sold at Sotheby's in 2010) and $1.8 million per carat for a 5.3-carat Fancy deep blue diamond (sold at Bonhams in London in April 2013).
DS201606-1093
2015
Gain, S.Howell, D., Griffin, W.L., Yang, J., Gain, S., Stern, R.A., Huang, J-X., Jacob, D.E., Xu, X., Stokes, A.J., O'Reilly, S.Y., Pearson, N.J.Diamonds in ophiolites: contamination or a new diamond growth environment?Earth and Planetary Science Letters, Vol. 430, pp. 284-295.Asia, TibetLuobusa Massif Type Iib

Abstract: For more than 20 years, the reported occurrence of diamonds in the chromites and peridotites of the Luobusa massif in Tibet (a complex described as an ophiolite) has been widely ignored by the diamond research community. This skepticism has persisted because the diamonds are similar in many respects to high-pressure high-temperature (HPHT) synthetic/industrial diamonds (grown from metal solvents), and the finding previously has not been independently replicated. We present a detailed examination of the Luobusa diamonds (recovered from both peridotites and chromitites), including morphology, size, color, impurity characteristics (by infrared spectroscopy), internal growth structures, trace-element patterns, and C and N isotopes. A detailed comparison with synthetic industrial diamonds shows many similarities. Cubo-octahedral morphology, yellow color due to unaggregated nitrogen (C centres only, Type Ib), metal-alloy inclusions and highly negative View the MathML sourcedC13 values are present in both sets of diamonds. The Tibetan diamonds (n=3n=3) show an exceptionally large range in View the MathML sourcedN15 (-5.6 to +28.7‰+28.7‰) within individual crystals, and inconsistent fractionation between {111} and {100} growth sectors. This in contrast to large synthetic HPHT diamonds grown by the temperature gradient method, which have with View the MathML sourcedN15=0‰ in {111} sectors and +30‰+30‰ in {100} sectors, as reported in the literature. This comparison is limited by the small sample set combined with the fact the diamonds probably grew by different processes. However, the Tibetan diamonds do have generally higher concentrations and different ratios of trace elements; most inclusions are a NiMnCo alloy, but there are also some small REE-rich phases never seen in HPHT synthetics. These characteristics indicate that the Tibetan diamonds grew in contact with a C-saturated Ni-Mn-Co-rich melt in a highly reduced environment. The stable isotopes indicate a major subduction-related contribution to the chemical environment. The unaggregated nitrogen, combined with the lack of evidence for resorption or plastic deformation, suggests a short (geologically speaking) residence in the mantle. Previously published models to explain the occurrence of the diamonds, and other phases indicative of highly reduced conditions and very high pressures, have failed to take into account the characteristics of the diamonds and the implications for their formation. For these diamonds to be seriously considered as the result of a natural growth environment requires a new understanding of mantle conditions that could produce them.
DS201606-1090
2016
Gain, S.E.Griffin, W.L., Afonso, J.C., Belousova, E.A., Gain, S.E., Gong, X-H., Gonzalez-Jiminez, J.M., Howell, D., Huang, J-X., McGowan, N., Pearson, N.J., Satsukawa, T., Shi R., Williams, P., Xiong, Q., Yang, J-S., Zhang, M., O'Reilly, S.Y.Mantle recycling: transition zone metamorphism of Tibetan ophiolitic peridotites and its tectonic implications.Journal of Petrology, in press available, 30p.Asia, China, TibetPeridotite

Abstract: Large peridotite massifs are scattered along the 1500?km length of the Yarlung-Zangbo Suture Zone (southern Tibet, China), the major suture between Asia and Greater India. Diamonds occur in the peridotites and chromitites of several massifs, together with an extensive suite of trace phases that indicate extremely low fO2 (SiC, nitrides, carbides, native elements) and/or ultrahigh pressures (UHP) (diamond, TiO2 II, coesite, possible stishovite). New physical and isotopic (C, N) studies of the diamonds indicate that they are natural, crystallized in a disequilibrium, high-T environment, and spent only a short time at mantle temperatures before exhumation and cooling. These constraints are difficult to reconcile with previous models for the history of the diamond-bearing rocks. Possible evidence for metamorphism in or near the upper part of the Transition Zone includes the following: (1) chromite (in disseminated, nodular and massive chromitites) containing exsolved pyroxenes and coesite, suggesting inversion from a high-P polymorph of chromite; (2) microstructural studies suggesting that the chromitites recrystallized from fine-grained, highly deformed mixtures of wadsleyite and an octahedral polymorph of chromite; (3) a new cubic Mg-silicate, with the space group of ringwoodite but an inverse-spinel structure (all Si in octahedral coordination); (4) harzburgites with coarsely vermicular symplectites of opx + Cr-Al spinel ± cpx; reconstructions suggest that these are the breakdown products of majoritic garnets, with estimated minimum pressures to?>?13?GPa. Evidence for a shallow pre-metamorphic origin for the chromitites and peridotites includes the following: (1) trace-element data showing that the chromitites are typical of suprasubduction-zone (SSZ) chromitites formed by magma mixing or mingling, consistent with Hf-isotope data from magmatic (375?Ma) zircons in the chromitites; (2) the composition of the new cubic Mg-silicate, which suggests a low-P origin as antigorite, subsequently dehydrated; (3) the peridotites themselves, which carry the trace element signature of metasomatism in an SSZ environment, a signature that must have been imposed before the incorporation of the UHP and low-fO2 phases. A proposed P-T-t path involves the original formation of chromitites in mantle-wedge harzburgites, subduction of these harzburgites at c. 375?Ma, residence in the upper Transition Zone for >200 Myr, and rapid exhumation at c. 170-150?Ma or 130-120?Ma. Os-isotope data suggest that the subducted mantle consisted of previously depleted subcontinental lithosphere, dragged down by a subducting oceanic slab. Thermomechanical modeling shows that roll-back of a (much later) subducting slab would produce a high-velocity channelized upwelling that could exhume the buoyant harzburgites (and their chromitites) from the Transition Zone in?
DS201910-2258
2019
Gain, S.E.Gain, S.E., Griffin, W.L., Saunders, M., Shaw, J.A., Toledo, V.A showcase of analytical techniques: native vanadium in hibonite and chromium in corundum: ultra-high contents under reducing conditions. Two posters Shefa Gems Microscopy and Microanalysis ( M&M)Co. Conference, Sept. 9, posters 1 p. eachEurope, Israeldeposit - Kishon

Abstract: The Microscopy and Microanalysis (M&M) conference in Portland Oregon, USA is one of the biggest microscopy conferences in the world and this year it hosted its largest meeting in history with over 3,300 participants, up to 20 parallel sessions and over 600 posters. The two posters were presented by Sarah E.M. Gain who is from the University of Western Australia where she trains and supports researchers in Microscopy, Characterisation and Microanalysis. Sarah discussed some of the unique gem material collected from Shefa Gems’ exploration activity in the Kishon Mid Reach and Rakefet Magmatic Complex, analysed using a range of microscopy and microanalysis techniques. She also discussed the scientific importance of this material.The first poster looked at hibonite (a Ca-Al-oxide) with inclusions of vanadium metal. The second poster looked at, Cr corundum (ruby), which is unusual due to the extremely high Cr levels and the inclusions of Cr metal.
DS201505-0246
2015
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Toledo, V., O'Reilly, S.Y., Jacob, D., Pearson, N.J.Corundum, moissanite and super reducing conditions in the upper mantle beneath the lower ( southern) Galilee ( Israel).Israel Geological Society, 1p.posterEurope, IsraelMineralogy
DS201603-0381
2016
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Adams, D., Huang, J-X., Saunders, M.,Toledo, V., Pearson, N.J., O'Reilly, S.Y.Heaven on Earth: tistarite ( Ti203) and other nebular phases in corundum aggregates from Mt. Carmel volcanic rocks.Israel Geological Society, pp. 85-86. abstractEurope, IsraelMoissanite

Abstract: This ending talk, focused on the ongoing cooperative research of Prof. Griffin and his team at Macquarie University and Shefa Yamim, since January 2014, highlighting unique corundum species characteristics. Preliminary results of this research were presented in the IGS Annual Meeting of 2015, whereas this year Prof. Griffin has shared innovative findings only microscopically tracked within titanium-rich corundum aggregates. One of the more abundant minerals is Tistarite (Ti2O3), previously known only as a single grain in a primitive type of meteorite (!). An article has been submitted to a scientific journal detailing this first terrestrial occurrence. Several other minerals are common in meteorites, but unknown or extremely rare on Earth. About half of these minerals are unknown to science, and will be described as new minerals in the scientific literature. The first of these is a Titanium-Aluminium-Zirconium oxide, informally known as TAZ; it will be submitted to the International Mineralogical Association for recognition as a new mineral, ShefaTAZite. Using state of the art technologies such as Thermal Ionisation Mass Spectrometry (TIMS) and Electron Microscopy Facility (EMF) that has three scanning electron microscopes, all with EBSD capability, and a transmission electron microscope - Prof. Griffin revealed spectacular imagery of minerals and rare compounds associated with titanium rich corundum aggregates.
DS201603-0382
2016
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Adams, D., Toledo, V., Pearson, N.J., O'Reilly, S.Y.Deep-Earth methane, mantle dynamics and mineral exploration: insights from northern Israel, southern Tibet and Kamchatka.Israel Geological Society, pp. 87-88. abstractEurope, Israel, TibetMoissanite
DS201610-1865
2016
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Adams, D.T., Huang, J-X., Saunders, M., Toledo, V., Pearson, N.J., O'Reilly, S.Y.First terrestrial occurrence of tistarite ( Ti2O3): ultra-low oxygen fugacity in the upper mantle beneath Mount Carmel, Israel.Geology, Vol. 44, 10, pp. 815-818.Europe, IsraelMoissanite

Abstract: The minimum oxygen fugacity (fO2) of Earth's upper mantle probably is controlled by metal saturation, as defined by the iron-wüstite (IW) buffer reaction (FeO ? Fe + O). However, the widespread occurrence of moissanite (SiC) in kimberlites, and a suite of super-reduced minerals (SiC, alloys, native elements) in peridotites in Tibet and the Polar Urals (Russia), suggest that more reducing conditions (fO2 = 6-8 log units below IW) must occur locally in the mantle. We describe pockets of melt trapped in aggregates of corundum crystals ejected from Cretaceous volcanoes in northern Israel which contain high-temperature mineral assemblages requiring extremely low fO2 (IW < -10). One abundant phase is tistarite (Ti2O3), previously known as a single grain in the Allende carbonaceous chondrite (Mexico) and believed to have formed during the early evolution of the solar nebula. It is associated with other reduced phases usually found in meteorites. The development of super-reducing conditions in Earth's upper mantle may reflect the introduction of CH4 + H2 fluids from the deep mantle, specifically related to deep-seated volcanic plumbing systems at plate boundaries.
DS201710-2280
2017
Gain, S.E.M.Xiong, Q., Griffin, W.L., Huang, J-X., Gain, S.E.M., Toledo, V., Pearson, N.J., O'Reilly, S.Y.Super reduced assemblages in "ophiolitic" chromitites and peridotites: the view from Mount Carmel.European Journal of Mineralogy, Vol. 29, 4, pp. 557-570.Europe, Israelmineralogy

Abstract: Ultrahigh-pressure (UHP) materials (e.g., diamond, high-pressure polymorph of chromite) and super-reduced (SuR) phases (e.g., carbides, nitrides, silicides and native metals) have been identified in chromitites and peridotites of the Tibetan and Polar-Urals ophiolites. These unusual assemblages suggest previously unrecognized fluid- or melt-related processes in the Earth’s mantle. However, the origin of the SuR phases, and in particular their relationships with the UHP materials in the ophiolites, are still enigmatic. Studies of a recently recognized SuR mineral system from Cretaceous volcanics on Mt Carmel, Israel, suggest an alternative genesis for the ophiolitic SuR phases. The Mt Carmel SuR mineral system (associated with Ti-rich corundum xenocrysts) appears to reflect the local interaction of mantle-derived CH4 ± H2 fluids with basaltic magmas in the shallow lithosphere (depths of ~30-100 km). These interactions produced desilication of the magma, supersaturation in Al2O3 leading to rapid growth of corundum, and phase assemblages requiring local oxygen fugacity (fO2) gradually dropping to ~11 log units below the iron-wüstite (IW) buffer. The strong similarities between this system and the SuR phases and associated Ti-rich corundum in the Tibetan and Polar-Urals ophiolites suggest that the ophiolitic SuR suite probably formed by local influx of CH4 ± H2 fluids within previously subducted peridotites (and included chromitites) during their rapid exhumation from the deep upper mantle to lithospheric levels. In the final stages of their ascent, the recycled peridotites and chromitites were overprinted by a shallow magmatic system similar to that observed at Mt Carmel, producing most of the SuR phases and eventually preserving them within the Tibetan and Polar-Urals ophiolites.
DS201806-1225
2018
Gain, S.E.M.Griffin, W.L., Huang, J-X., Thomassot, E., Gain, S.E.M., Toledo, V., O'Reilley, S.Y.Super reducing conditions in ancient and modern volcanic systems: sources and behaviour of carbon-rich fluids in the lithospheric mantle. Mt. Carmel moissaniteMineralogy and Petrology, in press available, 14p.Europe, Israelmetasomatism

Abstract: Oxygen fugacity (fO2) is a key parameter of Earth’s mantle, because it controls the speciation of the fluids migrating at depth; a major question is whether the sublithospheric mantle is metal-saturated, keeping fO2 near the Iron-Wustite (IW) buffer reaction. Cretaceous basaltic pyroclastic rocks on Mt. Carmel, Israel erupted in an intraplate environment with a thin, hot lithosphere. They contain abundant aggregates of hopper-shaped crystals of Ti-rich corundum, which have trapped melts with phenocryst assemblages (Ti2O3, SiC, TiC, silicides, native V) requiring extremely low fO2. These assemblages are interpreted to reflect interaction between basaltic melts and mantle-derived fluids dominated by CH4 + H2. Similar highly reduced assemblages are found associated with volcanism in a range of tectonic situations including subduction zones, major continental collisions, intraplate settings, craton margins and the cratons sampled by kimberlites. This distribution, and the worldwide similarity of d13C in mantle-derived SiC and associated diamonds, suggest a widespread process, involving similar sources and independent of tectonic setting. We suggest that the common factor is the ascent of abiotic (CH4 + H2) fluids from the sublithospheric mantle; this would imply that much of the mantle is metal-saturated, consistent with observations of metallic inclusions in sublithospheric diamonds (e.g. Smith et al. 2016). Such fluids, perhaps carried in rapidly ascending deep-seated magmas, could penetrate high up into a depleted cratonic root, establishing the observed trend of decreasing fO2 with depth (e.g. Yaxley et al. in Lithos 140:142-151, 2012). However, repeated metasomatism (associated with the intrusion of silicate melts) will raise the FeO content near the base of the craton over time, developing a carapace of oxidizing material that would prevent the rise of CH4-rich fluids into higher levels of the subcontinental lithospheric mantle (SCLM). Oxidation of these fluids would release CO2 and H2O to drive metasomatism and low-degree melting both in the carapace and higher in the SCLM. This model can explain the genesis of cratonic diamonds from both reduced and oxidized fluids, the existence of SiC as inclusions in diamonds, and the abundance of SiC in some kimberlites. It should encourage further study of the fine fractions of heavy-mineral concentrates from all types of explosive volcanism.
DS201808-1749
2018
Gain, S.E.M.Griffin, W.L., Huang, J-X., Thomassot, E., Gain, S.E.M., Toledo, V., O'Reilly, S.Y.Super-reducing conditions in ancient and modern volcanic systems: sources and behaviour of carbon-rich fluids in the lithospheric mantle ( Mt. Carmel).Mineralogy and Petrology, doi.org/10.1007/s00710-018-0575-x 14p.Mantlemoissanite
DS201810-2323
2018
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Huang, J.X., Belousova, E.A., Toledo, V., O'Reilly, S.Y.Permian to quaternary magmatism beneath the Mt. Carmel area, Israel: zircons from volcanic rocks and associated alluvial deposits.Lithos, Vol. 314-315, pp. 307-322.Europe, Israel zircons

Abstract: Xenocrystic zircons from Cretaceous pyroclastic vents on Mt. Carmel, N. Israel, document two major periods of earlier mafic magmatism: Permo-Triassic (285-220?Ma) and Jurassic (200-160?Ma). Related alluvial deposits also contain these zircon populations. However, most alluvial zircons are Cretaceous (118-80?Ma) or younger, derived from Miocene to Pliocene volcanic episodes. The Permo-Triassic-Jurassic zircons are typically large and glassy; they have irregular shapes and a wide variety of internal zoning patterns. They appear to have grown in the interstitial spaces of coarse-grained rocks; many show evidence of recrystallization, including brecciation and rehealing by chemically similar zircon. Grains with relict igneous zoning have mantle-like d18O (5.5?±?1.0‰), but brecciation leads to lower values (mean 4.8‰, down to 3.1‰). Hf-isotope compositions lie midway between the Chondritic Uniform Reservoir (CHUR) and Depleted Mantle (DM) reservoirs; Hf model ages suggest that the source region separated from DM in Neoproterozoic time (1500-1000?Ma). Most Cretaceous zircons have 176Hf/177Hf similar to those of the older zircons, suggesting recrystallization and/or Pb loss from older zircons in the Cretaceous thermal event. The Permo-Jurassic zircons show trace-element characteristics similar to those crystallized from plume-related magmas (Iceland, Hawaii). Calculated melts in equilibrium with them are characterized by strong depletion in LREE and P, large positive Ce anomalies, variable Ti anomalies, and high and variable Nb, Ta, Th and U, consistent with the fractionation of monazite, zircon, apatite and Ti-bearing phases. We suggest that these coarse-grained zircons crystallized from late differentiates of mafic magmas, ponded near the crust-mantle boundary (ca 30?km depth), and were reworked repeatedly by successively younger igneous/metasomatic fluids. The zircon data support a published model that locates a fossil Neoproterozoic plume head beneath much of the Arabia-Levant region, which has been intermittently melted to generate the volcanic rocks of the region. The Cretaceous magmas carry mantle xenoliths derived from depths up to 90?km, providing a minimum depth for the possible plume head. Post-Cretaceous magmatism, as recorded in detrital zircons, shows distinct peaks at 30?Ma, 13?Ma, 11.4?±?0.1?Ma (a major peak; n?=?15), 9-10?Ma and 4?Ma, representing the Lower and Cover Basalts in the area. Some of these younger magmas tapped the same mantle source as the Permian-Jurassic magmatism, but many young zircons have Hf-isotope compositions extending up to DM values, suggesting derivation of magmas from deeper, more juvenile sources.
DS201810-2360
2018
Gain, S.E.M.Nasdala, L., Corfu, F., Schoene, B., Tapster, S.R., Wall, C.J., Schmitz, M.D., Ovtcharova, M., Schaltegger, U., Kennedy, A.K., Kronz, A., Reiners, P.W., Yang, Y-H., Wu, F-Y., Gain, S.E.M., Griffin, W.L., Szymanowski, D., Chanmuang, C., Ende, N.M., ValleyGZ7 and GZ8 - two zircon reference materials for SIMS U-Pb geochronology.Geostandards and Geoanalytical Research, http://orchid.org/0000-0002-2701-4635 80p.Asia, Sri Lankageochronology

Abstract: Here we document a detailed characterization of two zircon gemstones, GZ7 and GZ8. Both stones had the same mass at 19.2 carats (3.84 g) each; both came from placer deposits in the Ratnapura district, Sri Lanka. The U-Pb data are in both cases concordant within the uncertainties of decay constants and yield weighted mean ²°6Pb/²³8U ages (95% confidence uncertainty) of 530.26 Ma ± 0.05 Ma (GZ7) and 543.92 Ma ± 0.06 Ma (GZ8). Neither GZ7 nor GZ8 have been subjected to any gem enhancement by heating. Structure-related parameters correspond well with the calculated alpha doses of 1.48 × 10¹8 g?¹ (GZ7) and 2.53 × 10¹8 g?¹ (GZ8), respectively, and the (U-Th)/He ages of 438 Ma ± 3 Ma (2s) for GZ7 and 426 Ma ± 9 Ma (2s) for GZ8 are typical of unheated zircon from Sri Lanka. The mean U concentrations are 680 µg g?¹ (GZ7) and 1305 µg g?¹ (GZ8). The two zircon samples are proposed as reference materials for SIMS (secondary ion mass spectrometry) U-Pb geochronology. In addition, GZ7 (Ti concentration 25.08 µg g?¹ ± 0.18 µg g?¹; 95% confidence uncertainty) may prove useful as reference material for Ti-in-zircon temperature estimates.
DS201902-0275
2018
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Bindi, L., Toledo, V., Camara, F., Saunders, M., O'Reilly, S.Y.Carmeltazite, ZrAl2Ti4011, a new mineral trapped in corundum from volcanic rocks of Mt Carmel, northern Israel.Minerals ( mdpi.com), Vol. 8, 12, 11p. PdfEurope, Israelmineralogy

Abstract: The new mineral species carmeltazite, ideally ZrAl2Ti4O11, was discovered in pockets of trapped melt interstitial to, or included in, corundum xenocrysts from the Cretaceous Mt Carmel volcanics of northern Israel, associated with corundum, tistarite, anorthite, osbornite, an unnamed REE (Rare Earth Element) phase, in a Ca-Mg-Al-Si-O glass. In reflected light, carmeltazite is weakly to moderately bireflectant and weakly pleochroic from dark brown to dark green. Internal reflections are absent. Under crossed polars, the mineral is anisotropic, without characteristic rotation tints. Reflectance values for the four COM wavelengths (Rmin, Rmax (%) (? in nm)) are: 21.8, 22.9 (471.1); 21.0, 21.6 (548.3), 19.9, 20.7 (586.6); and 18.5, 19.8 (652.3). Electron microprobe analysis (average of eight spot analyses) gave, on the basis of 11 oxygen atoms per formula unit and assuming all Ti and Sc as trivalent, the chemical formula (Ti3+3.60Al1.89Zr1.04Mg0.24Si0.13Sc0.06Ca0.05Y0.02Hf0.01)S=7.04O11. The simplified formula is ZrAl2Ti4O11, which requires ZrO2 24.03, Al2O3 19.88, and Ti2O3 56.09, totaling 100.00 wt %. The main diffraction lines, corresponding to multiple hkl indices, are (d in Å (relative visual intensity)): 5.04 (65), 4.09 (60), 2.961 (100), 2.885 (40), and 2.047 (60). The crystal structure study revealed carmeltazite to be orthorhombic, space group Pnma, with unit-cell parameters a = 14.0951 (9), b = 5.8123 (4), c = 10.0848 (7) Å, V = 826.2 (1) Å3, and Z = 4. The crystal structure was refined to a final R1 = 0.0216 for 1165 observed reflections with Fo > 4s(Fo). Carmeltazite exhibits a structural arrangement similar to that observed in a defective spinel structure. The name carmeltazite derives from Mt Carmel (“CARMEL”) and from the dominant metals present in the mineral, i.e., Titanium, Aluminum and Zirconium (“TAZ”). The mineral and its name have been approved by the IMA Commission on New Minerals, Nomenclature and Classification (2018-103).
DS201903-0514
2019
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Huang, J-X., Saunders, M., Shaw, J., Toledo, V., O'Reilly, S.Y.A terrestrial magmatic hibonite-grossite-vanadium assemblage: desilication and extreme reduction in a volcanic plumbing system, Mount Carmel, Israel.American Mineralogist, Vol. 104, pp. 207-219.Europe, Israelmelting

Abstract: Hibonite (CaAl12O19) is a constituent of some refractory calcium-aluminum inclusions (CAIs) in carbonaceous meteorites, commonly accompanied by grossite (CaAl4O7) and spinel. These phases are usually interpreted as having condensed, or crystallized from silicate melts, early in the evolution of the solar nebula. Both Ca-Al oxides are commonly found on Earth, but as products of high-temperature metamorphism of pelitic carbonate rocks. We report here a unique occurrence of magmatic hibonitegrossite-spinel assemblages, crystallized from Ca-Al-rich silicate melts under conditions [high-temperature, very low oxygen fugacity (fO2)] comparable to those of their meteoritic counterparts. Ejecta from Cretaceous pyroclastic deposits on Mt Carmel, N. Israel, include aggregates of hopper/skeletal Ti-rich corundum, which have trapped melts that crystallized at fO2 extending from 7 log units below the iron-wustite buffer (?IW = -7; SiC, Ti2O3, Fe-Ti silicide melts) to ?IW = -9 (native V, TiC, and TiN). The assemblage hibonite + grossite + spinel + TiN first crystallized late in the evolution of the melt pockets; this hibonite contains percentage levels of Zr, Ti, and REE that reflect the concentration of incompatible elements in the residual melts as corundum continued to crystallize. A still later stage appears to be represented by coarse-grained (centimeter-size crystals) ejecta that show the crystallization sequence: corundum + Liq ? (low-REE) hibonite ? grossite + spinel ± krotite ? Ca4Al6F2O12 + fluorite. V0 appears as spheroidal droplets, with balls up to millimeter size and spectacular dendritic intergrowths, included in hibonite, grossite, and spinel. Texturally late V0 averages 12 wt% Al and 2 wt% Mn. Spinels contain 10-16 wt% V in V0-free samples, and <0.5 wt% V in samples with abundant V 0. Ongoing paragenetic studies suggest that the fO2 evolution of the Mt Carmel magmatic system reflects the interaction between OIB-type mafic magmas and mantle-derived CH4+H2 fluids near the crust-mantle boundary. Temperatures estimated by comparison with 1 atm phase-equilibrium studies range from ca. 1500 °C down to 1200-1150 °C. When fO2 reached ca. ?IW = -7, the immiscible segregation of Fe,Ti-silicide melts and the crystallization of SiC and TiC effectively desilicated the magma, leading to supersaturation in Al2O3 and the rapid crystallization of corundum, preceding the development of the hibonite-bearing assemblages. Reports of Ti-rich corundum and SiC from other areas of explosive volcanism suggest that these phenomena may be more widespread than presently realized, and the hibonite-grossite assemblage may serve as another indicator to track such activity. This is the first reported terrestrial occurrence of krotite (CaAl2O4), and of at least two unknown Zr-Ti oxides.
DS201906-1276
2019
Gain, S.E.M.Bindi, L., Camara, F., Griffin, W.L., Huang, J-X., Gain, S.E.M., Toledo, V., O'Reilly, S.Y.Discovery of the first natural hydride. Mt. CarmelAmerican Mineralogist, Vol. 104, pp. 611-614.Europe, Israelcrystallography

Abstract: Although hydrogen is the most abundant element in the solar system, the mechanisms of exchange of this element between the deep interior and surface of Earth are still uncertain. Hydrogen has profound effects on properties and processes on microscopic-to-global scales. Here we report the discovery of the first hydride (VH2) ever reported in nature. This phase has been found in the ejecta of Cretaceous pyroclastic volcanoes on Mt Carmel, N. Israel, which include abundant xenoliths containing highly reduced mineral assemblages. These xenoliths were sampled by their host magmas at different stages of their evolution but are not genetically related to them. The xenoliths are interpreted as the products of extended interaction between originally mafic magmas and CH4+H2 fluids, derived from a deeper, metal-saturated mantle. The last stages of melt evolution are recorded by coarse-grained aggregates of hibonite (CaAl12O19) + grossite (CaAl4O7) + V-rich spinels ± spheroidal to dendritic inclusions of metallic vanadium (V0), apparently trapped as immiscible metallic melts. The presence of V0 implies low oxygen fugacities and suggests crystallization of the aggregates in a hydrogen-rich atmosphere. The presence of such reducing conditions in the upper mantle has major implications for the transport of carbon, hydrogen and other volatile species from the deep mantle to the surface.
DS201906-1293
2019
Gain, S.E.M.Gain, S.E.M., Greau, Y., Henry, H., Belousova, E., Dainis, I., Griffin, W.L., O'Reilly, S.Y.Mud Tank zircon: long term evaluation of a reference material for U-Pb dating, Hf-isotope analysis and trace element analysis. ( Carbonatite)Geostandards and Geoanalytical Research, in press available, 16p.Australiadeposit - Mud Tank

Abstract: Zircon megacrysts from the Mud Tank carbonatite, Australia, are being used in many laboratories as a reference material for LA-ICP-MS U-Pb dating and trace element measurement, and LA-MC-ICP-MS determination of Hf isotopes. We summarise a database of > 10000 analyses of Mud Tank zircon (MTZ), collected from 2000 to 2018 during its use as a secondary reference material for simultaneous U-Pb and trace element analysis, and for Hf-isotope analysis. Trace element mass fractions are highest in dark red-brown stones and lowest in colourless and gem-quality ones. Individual unzoned grains can be chemically homogeneous, while significant variations in trace element mass fraction are associated with oscillatory zoning. Chondrite-normalised trace element patterns are essentially parallel over large mass fraction ranges. A Concordia age of 731.0 ± 0.2 Ma (2s, n = 2272) is taken as the age of crystallisation. Some grains show lower concordant to mildly discordant ages, probably reflecting minor Pb loss associated with cooling and the Alice Springs Orogeny (450-300 Ma). Our weighted mean 176Hf/177Hf is 0.282523 ± 10 (2s, n = 9350); the uncertainties on this ratio reflect some heterogeneity, mainly between grains. A few analyses suggest that colourless grains have generally lower 176Hf/177Hf. MTZ is a useful secondary reference material for U-Pb and Hf-isotope analysis, but individual grains need to be carefully selected using CL imaging and tested for homogeneity, and ideally should be standardised by solution analysis.
DS202012-2217
2020
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Saunders, M., Bindi, L., Alard, O., Toledo, V., O'Reilly, S.Y.Parageneses of TiB2 in corundum xenoliths from Mt. Carmel, Israel: siderophile behavior of boron under reducing conditions.American Mineralogist, Vol. 105, pp. 1609-1621. pdfEurope, Israeldeposit - Mt. Carmel

Abstract: Titanium diboride (TiB2) is a minor but common phase in melt pockets trapped in the corundum aggregates that occur as xenoliths in Cretaceous basaltic volcanoes on Mt. Carmel, north Israel. These melt pockets show extensive textural evidence of immiscibility between metallic (Fe-Ti-C-Si) melts, Ca-Al-Mg-Si-O melts, and Ti-(oxy)nitride melts. The metallic melts commonly form spherules in the coexisting oxide glass. Most of the observed TiB2 crystallized from the Fe-Ti-C silicide melts and a smaller proportion from the oxide melts. The parageneses in the melt pockets of the xenoliths require fO2 = ?IW-6, probably generated through interaction between evolved silicate melts and mantle-derived CH4+H2 fluids near the crust-mantle boundary. Under these highly reducing conditions boron, like carbon and nitrogen, behaved mainly as a siderophile element during the separation of immiscible metallic and oxide melts. These parageneses have implications for the residence of boron in the peridotitic mantle and for the occurrence of TiB2 in other less well-constrained environments such as ophiolitic chromitites.
DS202101-0001
2020
Gain, S.E.M.Bindi, L., Camara, F., Gain, S.E.M., Griffin, W.L., Huang, J-X., Saunders, M., Toledo, V.Kishonite, VH2 and oreillyite, Cr2N, two new minerals from the conundrum xenocrysts of Mt. Carmel, northern Israel.Minerals MDPI, Vol. 10, 1118, doi:10.3390/ min10121118 10p. PdfEurope, Israeldeposit - Mt. Carmel

Abstract: Here, we describe two new minerals, kishonite (VH2) and oreillyite (Cr2N), found in xenoliths occurring in pyroclastic ejecta of small Cretaceous basaltic volcanoes exposed on Mount Carmel, Northern Israel. Kishonite was studied by single-crystal X-ray diffraction and was found to be cubic, space group Fm3¯m, with a = 4.2680(10) Å, V = 77.75(3) Å3, and Z = 4. Oreillyite was studied by both single-crystal X-ray diffraction and transmission electron microscopy and was found to be trigonal, space group P3¯1m, with a = 4.7853(5) Å, c = 4.4630(6) Å, V = 88.51 Å3, and Z = 3. The presence of such a mineralization in these xenoliths supports the idea of the presence of reduced fluids in the sublithospheric mantle influencing the transport of volatile species (e.g., C, H) from the deep Earth to the surface. The minerals and their names have been approved by the Commission of New Minerals, Nomenclature and Classification of the International Mineralogical Association (No. 2020-023 and 2020-030a).
DS202101-0013
2020
Gain, S.E.M.Griffin, W.L., Gain, S.E.M., Saunders, M., Bindi, L., Alard, O., Toledo, V., O'Reilly, S.Y.Parageneses of TIB2 in corundum xenoliths from Mt. Carmel, Israel: siderophile behaviour of boron under reducing conditions.American Mineralogist , in press available 33p. PdfEurope, Israeldeposit - Mt. Carmel

Abstract: Titanium diboride (TiB2) is a minor but common phase in melt pockets trapped in the corundum aggregates that occur as xenoliths in Cretaceous basaltic volcanoes on Mt. Carmel, north Israel. These melt pockets show extensive textural evidence of immiscibility between metallic (Fe-Ti-C-Si) melts, Ca-Al-Mg-Si-O melts, and Ti-(oxy)nitride melts. The metallic melts commonly form spherules in the coexisting oxide glass. Most of the observed TiB2 crystallized from the Fe-Ti-C silicide melts and a smaller proportion from the oxide melts. The parageneses in the melt pockets of the xenoliths require fO2 = ?IW-6, probably generated through interaction between evolved silicate melts and mantle-derived CH4+H2 fluids near the crust-mantle boundary. Under these highly reducing conditions boron, like carbon and nitrogen, behaved mainly as a siderophile element during the separation of immiscible metallic and oxide melts. These parageneses have implications for the residence of boron in the peridotitic mantle and for the occurrence of TiB2 in other less well-constrained environments such as ophiolitic chromitites.
DS2001-0813
2001
Gaina, C.Muller, R.D., Gaina, C., Roest, W.R., KLunbek HansenA recipe for microcontinent formationGeology, Vol. 29, No. 3, Mar. pp.203-6.GreenlandPlumes, accretion, terranes, Tectonics
DS200412-0601
2004
Gaina, C.Gaina, C., Muller, R.D., Brown, B.J., Ishihara, T.Microcontinent formation around Australia.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 405-416.AustraliaTectonics
DS200412-1378
2004
Gaina, C.Muller, R.D., Gaina, C.Tectonic evolution of the southwest Pacific using constraints from backarc basins.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 343-360.AustraliaTectonics
DS200412-1379
2004
Gaina, C.Muller, R.D., Gaina, C., Struckmeyer, H.I.M., Stagg, H.M.J., Symonds, P.A.Formation and evolution of Australian passive margins: implications for locating the boundary between continental and oceanic crHillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 223-244.AustraliaTectonics
DS200812-0024
2008
Gaina, C.Alvey, A., Gaina, C.,Kusznir, N.J., Torsvik, T.H.Integrated crustal thickness mapping and plate reconstructions for the high Arctic.Earth and Planetary Science Letters, In press availableCanada, Arctic, GreenlandTectonics, plate, lithosphere
DS201012-0793
2010
Gaina, C.Torsvik, T.H., Steinberger, B., Gurnis, M., Gaina, C.Plate tectonics and net lithosphere rotation over the past 150 My.Earth and Planetary Science Letters, Vol. 291, 1-4, pp. 106-112.MantleTectonics
DS201112-1074
2011
Gaina, C.Van Hinsbergen, D.J.J., Buiter, S.J.H., Torsvik, T.H., Gaina, C., Webb, S.J.The formation and evolution of Africa from the Archean to Present; introduction.The Formation and Evolution of Africa: A synopsis of 3.8 Ga of Earth History, Geol. Soc. London Special Publ., 357, pp. 1-8.AfricaHistory
DS201606-1116
2016
Gaina, C.Shephard, G.E., Tronnes, R.G., Spakman, W., Panet, I., Gaina, C.Evidence of slab material under Greenland and links to Cretaceous high Arctic magmatism.Geophysical Research Letters, Vol. 43, 8, pp. 3717-3726.Europe, GreenlandMagmatism

Abstract: Understanding the evolution of extinct ocean basins through time and space demands the integration of surface kinematics and mantle dynamics. We explore the existence, origin, and implications of a proposed oceanic slab burial ground under Greenland through a comparison of seismic tomography, slab sinking rates, regional plate reconstructions, and satellite-derived gravity gradients. Our preferred interpretation stipulates that anomalous, fast seismic velocities at 1000-1600?km depth imaged in independent global tomographic models, coupled with gravity gradient perturbations, represent paleo-Arctic oceanic slabs that subducted in the Mesozoic. We suggest a novel connection between slab-related arc mantle and geochemical signatures in some of the tholeiitic and mildly alkaline magmas of the Cretaceous High Arctic Large Igneous Province in the Sverdrup Basin. However, continental crustal contributions are noted in these evolved basaltic rocks. The integration of independent, yet complementary, data sets provides insight into present-day mantle structure, magmatic events, and relict oceans.
DS201607-1315
2016
Gaina, C.Shephard, G.E., Tronnes, R.G., Sparkman< W., Panet, I., Gaina, C.Evidence for slab material under Greenland and links to Cretaceous High Arctic magmatism.Geophysical Research Letters, Vol. 43, 8, pp. 3717-3726.Europe, GreenlandMagmatism

Abstract: Understanding the evolution of extinct ocean basins through time and space demands the integration of surface kinematics and mantle dynamics. We explore the existence, origin, and implications of a proposed oceanic slab burial ground under Greenland through a comparison of seismic tomography, slab sinking rates, regional plate reconstructions, and satellite-derived gravity gradients. Our preferred interpretation stipulates that anomalous, fast seismic velocities at 1000 -1600?km depth imaged in independent global tomographic models, coupled with gravity gradient perturbations, represent paleo-Arctic oceanic slabs that subducted in the Mesozoic. We suggest a novel connection between slab-related arc mantle and geochemical signatures in some of the tholeiitic and mildly alkaline magmas of the Cretaceous High Arctic Large Igneous Province in the Sverdrup Basin. However, continental crustal contributions are noted in these evolved basaltic rocks. The integration of independent, yet complementary, data sets provides insight into present-day mantle structure, magmatic events, and relict oceans.
DS201612-2337
2016
Gaina, C.Shephard, G.E., Tronnes, R.G., Spakman, W., Panet, I., Gaina, C.Evidence for slab material under Greenland and links to Cretaceous high arctic magmatism.Geophysical Research Letters, Vol. 7, 10.1002/ 2016GL068424Europe, GreenlandMagmatism

Abstract: Understanding the evolution of extinct ocean basins through time and space demands the integration of surface kinematics and mantle dynamics. We explore the existence, origin, and implications of a proposed oceanic slab burial ground under Greenland through a comparison of seismic tomography, slab sinking rates, regional plate reconstructions, and satellite-derived gravity gradients. Our preferred interpretation stipulates that anomalous, fast seismic velocities at 1000-1600?km depth imaged in independent global tomographic models, coupled with gravity gradient perturbations, represent paleo-Arctic oceanic slabs that subducted in the Mesozoic. We suggest a novel connection between slab-related arc mantle and geochemical signatures in some of the tholeiitic and mildly alkaline magmas of the Cretaceous High Arctic Large Igneous Province in the Sverdrup Basin. However, continental crustal contributions are noted in these evolved basaltic rocks. The integration of independent, yet complementary, data sets provides insight into present-day mantle structure, magmatic events, and relict oceans.
DS201904-0737
2019
Gaina, C.Gaina, C., Niocaill, C.M., Conrad, C.P., Steinberger, B., Svensen, H.H.Linking plate tectonics and volcanism to deep Earth dynamics - a tribute to Torsvik.Tectonophysics, in press available 6p.Mantlegeodynamics
DS201909-2056
2019
Gaina, C.Lebedeva-Ivanova, N., Gaina, C., Minakov, A., Kashubin, S.ArcCRUST: Arctic crustal thickness from 3-D gravity inversion.Geochemistry, Geophysics, Geosystems, Vol. 20 doi.org/10.1029 /2018GC008098Globalgeophysics - gravity

Abstract: An excess or deficit of mass is reflected in the gravity anomaly data. Gravity anomalies measured by satellite and airborne and shipborne instruments show variations in topography and bathymetry, sedimentary thickness, basement rock density contrast, crustal thickness, and even mantle convection. Using new geophysical data and an improved 3-D gravity inversion method, we calculate the crustal thickness of oceanic domains in the High Arctic and northern North Atlantic. This model helps to better understand the tectonic structure of poorly surveyed and difficult to access Arctic regions. ArcCRUST can be used to better constrain the deeper Arctic region structure.
DS202008-1453
2020
Gaina, C.van den Broeck, J.M., Gaina, C.Microcontinents and continental fragments associated with subduction systems.Tectonics, in press available, e2020TC006063 39p. PdfGlobalsubduction

Abstract: Microcontinents and continental fragments are small pieces of continental crust that are surrounded by oceanic lithosphere. Although classically associated with passive margin formation, here we present several preserved microcontinents and continental fragments associated with subduction systems. They are located in the Coral Sea, South China Sea, central Mediterranean and Scotia Sea regions and a ‘proto-microcontinent’, in the Gulf of California. Reviewing the tectonic history of each region and interpreting a variety of geophysical data allows us to identify parameters controlling the formation of microcontinents and continental fragments in subduction settings. All these tectonic blocks experienced long, complex tectonic histories with an important role for developing inherited structures. They tend to form in back-arc locations and separate from their parent continent by oblique or rotational kinematics. The separated continental pieces and associated marginal basins are generally small and formation is quick (<50 Myr). Microcontinents and continental fragments formed close to large continental masses tend to form faster than those created in systems bordered by large oceanic plates. A common triggering mechanism for formation is difficult to identify, but seems to be linked with rapid changes of complex subduction dynamics. The young ages of all contemporary pieces found in situ suggest that microcontinents and continental fragments in these settings are short lived. Although presently the amount of in-situ subduction-related microcontinents is meagre (an area of 0.56% and 0.28% of global, non-cratonic, continental crustal area and crustal volume respectively), through time microcontinents contributed to terrane amalgamation and larger continent formation.
DS202009-1672
2020
Gaina, C.van den Broek, J.M., Gaina, C.Microcontinents and continental fragments associated with subduction systems.Tectonics, 10.1029/2020/TC006063 29p. PdfGlobalsubduction

Abstract: Microcontinents and continental fragments are small pieces of continental crust that are surrounded by oceanic lithosphere. Although classically associated with passive margin formation, here we present several preserved microcontinents and continental fragments associated with subduction systems. They are located in the Coral Sea, South China Sea, central Mediterranean and Scotia Sea regions, and a “proto-microcontinent,” in the Gulf of California. Reviewing the tectonic history of each region and interpreting a variety of geophysical data allows us to identify parameters controlling the formation of microcontinents and continental fragments in subduction settings. All these tectonic blocks experienced long, complex tectonic histories with an important role for developing inherited structures. They tend to form in back-arc locations and separate from their parent continent by oblique or rotational kinematics. The separated continental pieces and associated marginal basins are generally small and their formation is quick (<50 Myr). Microcontinents and continental fragments formed close to large continental masses tend to form faster than those created in systems bordered by large oceanic plates. A common triggering mechanism for their formation is difficult to identify, but seems to be linked with rapid changes of complex subduction dynamics. The young ages of all contemporary pieces found in situ suggest that microcontinents and continental fragments in these settings are short lived. Although presently the amount of in-situ subduction-related microcontinents is meager (an area of 0.56% and 0.28% of global, non-cratonic, continental crustal area and crustal volume, respectively), through time microcontinents contributed to terrane amalgamation and larger continent formation.
DS201312-0387
2011
Gaina, G.Hinsbergen, D.J.J., Buiter, S.J.H., Torsvik, T.H., Gaina, G., Webb, S.J.Formation and evolution of Africa: a synopsis of 3.8 Ga of Earth history.Geological Society of London, Special Publication no. 357, 378p. Approx 120 lbsAfricaTectonics
DS201708-1643
2017
Gainer, D.Gainer, D.The geology of the Faraday 3 kimberlite, NWT, Canada.11th. International Kimberlite Conference, PosterCanada, Northwest Territoriesdeposit - Faraday 3
DS1989-0359
1989
Gaines, P.R.Dismukes, J.P., Gaines, P.R., Witzke, H., Leta, D.P., Kear, B.H.Demineralization and microstructure of carbonadoMater. Sci. Eng. Proceedings 'A struct. mater. prop. microstruct. Proceedings', Vol. 105-106, Dec.3rd International Sci Conference Hard Mat.pp. 555-63GlobalCarbonado
DS1997-0367
1997
Gaines, R.V.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
DS1940-0046
1942
Gainier, P.W.Gainier, P.W.Green FireNew York: Random House., 296P.GlobalKimberlite, Kimberley, Janlib, Emerald
DS201212-0651
2012
Gainutdinov, R.Shiryaev, A., Gainutdinov, R., Fedortchouk, Y.Deformation induced defects in diamonds: contribution of small angle X-ray scattering and atomic force microscopy.emc2012 @ uni-frankfurt.de, 1p. AbstractTechnologyDiamond microscopy
DS201312-0289
2013
Gainutdinov, R.V.Gainutdinov, R.V., Shiryaev, A.A., Boyko, V.S., Fedortchouk, Y.Extended defects in natural diamonds: an atomic force microscopy investigation.Diamond and Related Materials, Vol. 40, pp. 17-23.TechnologyDiamond morphology
DS1950-0272
1956
Gair, J.E.Gair, J.E., Wier, K.L.Geology of the Kiernan Qaudrangle, Iron County, MichiganUnited States Geological Survey (USGS) Bulletin., No. 1044, 88P.United States, Michigan, Great LakesRegional Geology
DS200512-0250
2005
Gaister, A.V.Dudnikova, V.B., Gaister, A.V., Zharikov, E.V., Senin, V.G., Urusov, V.S.Chromium distribution between forsterite and its melt: dependence on chromium content in melt and redox conditions.Geochemistry International, Vol. 43, 5, pp. 471-477.MantleMelting
DS200712-0341
2007
Gait, A.D.Gait, A.D., Lowman, J.P.Time dependence in mantle convection models featuring dynamically evolving plates.Geophysical Journal International, Vol. 171, 1, October pp. 463-477.MantleConvection
DS200712-0342
2007
Gait, A.D.Gait, A.D., Lowman, J.P.Time dependence in mantle convection models featuring dynamically evolving plates.Geophysical Journal International, Vol. 171, 1, pp. 463-477.MantleConvection
DS200812-0377
2007
Gait, A.D.Gait, A.D., Lowman, J.P.Effect of lower mantle viscosity on the time dependence of plate velocities in three dimensional mantle convection models.Geophysical Research Letters, Vol. 34, 21, Nov. 16, ppp. L21304-07.MantleConvection
DS200812-0378
2008
Gait, A.D.Gait, A.D., Lowman, J.P., Gable, C.W.Time dependence in 3 D mantle convection models featuring evolving plates: effect of lower mantle viscosity.Journal of Geophysical Research, Vol. 113, B08409.MantleGeophysics - seismcis
DS200812-0379
2008
Gait, A.D.Gait, A.D., Lowman, J.P., Gable, C.W.Time dependence in 3 D mantle convection models featuring evolving plates: effect of lower mantle viscosity.Journal of Geophysical Research, Vol. 113, B8, B80409.MantleGeophysics - seismics
DS200912-0455
2008
Gait, A.D.Lowman, J.P., Gait, A.D., Gable, C.W., Kukreja, H.Plumes anchored by a high velocity lower mantle in a 3D mantle convection model featuring dynamically evolving plates.Geophysical Research Letters, Vol. 35, 19, Oct. 16, GLO35342MantleHotspots
DS2003-0506
2003
Gaitzsch, I.Grimmer, J.C., Ratschbacher, L., McWilliams, M., Franz, L., Gaitzsch, I., et al.When did the ultrahigh-pressure rocks reach the surface? A 207Pb 206 Pb zircon 40Chemical Geology, Vol. 197, 1-4, pp. 87-110.ChinaDabie Shan synorogenic foreland sediments, UHP
DS200412-0728
2003
Gaitzsch, I.Grimmer, J.C., Ratschbacher, L., McWilliams, M., Franz, L., Gaitzsch, I., et al.When did the ultrahigh-pressure rocks reach the surface? A 207Pb 206 Pb zircon 40 Ar 39Ar white mica, Si in white mica, single gChemical Geology, Vol. 197, 1-4, pp. 87-110.ChinaDabie Shan synorogenic foreland sediments UHP
DS200512-0068
2001
Gakhova, L.N.Baryshnikov, V.D., Gakhova, L.N., Kramskov, N.P.Stress state of the rock mass in the vicinity of underground mining workings, pit edges, and below its bottom.Journal of Mining Science, Vol. 37, 5, pp. 462-465.RussiaMining - Aikhal
DS200512-0069
2002
Gakhova, L.N.Baryshnikov, V.D., Gakhova, L.N., Kramskov, N.P.Stress state of ore mass in the ascending slice system.Journal of Mining Science, Vol. 38, 6, pp. 608-611.RussiaMining - International
DS200912-0036
2009
Gakhova, L.N.Baryshnikov, V.D., Gakhova, L.N.Geomechanical conditions of kimberlite extraction in terms of Internatsionalnaya kimberlite pipe,Journal of Mining Science, Vol. 45, 2, pp. 137-145.RussiaMining
DS1998-0460
1998
Gala, M.G.Gala, M.G., Symons, D.T.A., Palmer, H.C.Geotectonics of the Hanson Lake block, Trans-Hudson orogen: preliminary paleomagnetic report.Precambrian Research, Vol. 90, No. 1-2, June 30. pp. 85-?ManitobaTectonics, Orogeny
DS1988-0232
1988
Galakhov, A.V.Galakhov, A.V.Khibiny massif- a complex central type polychamber intrusive.(in Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 302, No. 3, pp. 673-675RussiaCarbonatite
DS1985-0548
1985
Galakhova, T.N.Pripachkin, V.A., Pavlova, M.A., Galakhova, T.N., et al.Bitumens of Khibini CarbonatitesDoklady Academy of Sciences Nauk SSSR., Vol. 281, No. 6, PP. 1424-1426.RussiaBlank
DS1986-0655
1986
Galakhova, T.N.Pripachkin, V.A., Pavlova, N.A., Galakhova, T.N., VolokhovaBitumens in carbonatites of the KhibinyDoklady Academy of Science USSR, Earth Science Section, Vol. 281, No. 1-6, November pp. 137-140RussiaCarbonatite
DS1960-1105
1969
Galanov, S.I.Galanov, S.I., et al.On Prospecting for Kimberlite Bodies in East SayanEastern Siberian Publishing House, Yakutsk., Russia, YakutiaKimberlite, Geophysics
DS201812-2786
2018
Galarneau, M.Bulbuc, K.M., Galarneau, M., Stachel, T., Stern, R.A., Kong, J., Chinn, I.Contrasting growth conditions for sulphide-and garnet-included diamonds from the Victor mine ( Ontario).2018 Yellowknife Geoscience Forum , p. 97-98. abstractCanada, Ontario, Attawapiskatdeposit - Victor

Abstract: The Victor Diamond Mine, located in the Attawapiskat kimberlite field (Superior Craton), is known for its exceptional diamond quality. Here we study the chemical environment of formation of Victor diamonds. We imaged eight sulphide-included diamond plates from Victor using cathodoluminescence (CL). Then, along core-rim transects, we measured nitrogen content and aggregation state utilizing Fourier Transform Infrared (FTIR) spectroscopy, and the stable isotope compositions of carbon (d13C) and nitrogen (d15N), using a multi-collector ion microprobe (MC-SIMS). We compare the internal growth features and chemical characteristics of these sulphide inclusion-bearing diamonds with similar data on garnet inclusion-bearing diamonds from Victor (BSc thesis Galarneau). Using this information, possible fractionation processes during diamond precipitation are considered and inferences on the speciation of the diamond forming fluid(s) are explored. Sulphide inclusion-bearing diamonds show much greater overall complexity in their internal growth features than garnet inclusion-bearing diamonds. Two of the sulphide-included samples have cores that represent an older generation of diamond growth. Compared to garnet inclusion-bearing diamonds, the sulphide-included diamonds show very little intra-sample variation in both carbon and nitrogen isotopic composition; the inter-sample variations in carbon isotopic composition, however, are higher than in garnet included diamonds. For sulphide-included diamonds, d13C ranges from -3.4 to -17.5 and d15N ranges from -0.2 to -9.2. Garnet inclusion-bearing diamonds showed d13C values ranging from -4.6 to -6.0 and d15N ranging from -2.8 to -10.8. The observation of some 13C depleted samples indicates that, unlike the lherzolitic garnet inclusion-bearing diamonds, the sulphide inclusion-bearing diamonds are likely both peridotitic and eclogitic in origin. The total range in N content across sulphide inclusion-bearing diamonds was 2 to 981 at ppm, similar to the garnet-included samples with a range of 5 to 944 at ppm. The very limited variations in carbon and nitrogen isotopic signatures across growth layers indicate that sulphide-included Victor diamonds grew at comparatively high fluid:rock ratios. This is contrasted by the garnet inclusion-bearing diamonds that commonly show the effects of Rayleigh fractionation and hence grew under fluid-limited conditions.
DS1990-0504
1990
Galasso, F.S.Galasso, F.S.Perovskites and high TC superconductorsGordon and Breach Publk, Book 293p. approx. $ 110.00 ISBN 2-88124-391-6GlobalPerovskites, Superconductors
DS201112-0100
2011
Galbrun, B.Boulila, S., Galbrun, B., Miller, K.G., Pekar, S.F., Browning, J.V., Laskar, J., Wright, J.D.On the origin of Cenozoic and Mesozoic 'third order' eustatic sequences.Earth Science Reviews, Vol. 109, 3-4, pp. 94-112.GlobalGeomorphology - sea levels
DS201012-0800
2009
Galchenko, Y.P.Trubetskoy, K.N., Galchenko, Y.P., Ainbinder, L.L., Sabinyan, G.V.Outlook for the enhanced safety and improved efficiency of diamond deposit mining.Journal of Mining Science, Vol. 45, 6, pp. 581-590.RussiaMining - Yakutia pipes
DS2001-0351
2001
Galdeano, A.Galdeano, A., Asifirane, F., Nehlig, P.When was Arabia close to the pole?Earth and Planetary Science Letters, Vol. 193, No. 1-2, Nov. 30, pp. 25-37.ArabiaPaleomagnetism, Gondwanaland, Rodinia
DS200712-0767
2007
Galdeano, A.Muundjua, M., Hart, R.J., Gilder, S.A., Carporzen, L., Galdeano, A.Magnetic imaging of the Vredefort impact crater, South Africa.Earth and Planetary Science Letters, Vol. 261, 3-4, pp. 456-468.Africa, South AfricaGeophysics
DS1998-0797
1998
Galdin, N.E.Kouznetsova, E.I., Galdin, N.E.Continental lithosphere deep structure researches on the base of scientific deep drilling.7th International Kimberlite Conference Abstract, pp. 469-0.Russia, Kola PeninsulaMantle - lithosphere, Pechenga Structure, Baltic Shield
DS201412-0162
2014
Gale, A.Dalton, C.A., Langmuir, C.H., Gale, A.Report geophysical and geochemical evidence for deep temperature variations beneath mid-Ocean ridges.Science, Vol. 344, no. 6179, pp. 80-83.MantleGeophysics - seismics
DS1998-0653
1998
Gale, D.Indares, A., Dunning, G., Cox, R., Gale, D.high pressure high temperature rocks from the base of thick continentalcrust: Manicouagan imbricate zone.Tectonics, Vol. 17, No. 3, June pp. 426-40.Quebec, Labrador, Ungavametamorphism
DS1975-0598
1977
Gale, N.H.Paul, D.K., Gale, N.H., Harris, P.G.Uranium and Thorium Abundances in Indian KimberlitesGeochimica Et Cosmochimica Acta, Vol. 41, No. 2, PP. 335-339.IndiaIsotope
DS1980-0056
1980
Gale, N.H.Beckinsale, R.D., Gale, N.H., Parkhurst, R.J., Macfarlane, A.C.Discordant Rubidium-strontium and Lead Whole Rock Isochron Ages for ThePrecambrian Research., Vol. 13, No. 1, PP. 43-62.Sierra Leone, West AfricaGeochronology, Geology
DS1994-0321
1994
Galeotti, S.Coccioni, R., Galeotti, S.K-T boundary extinction: geologically instantaneous or gradual event?Evidence deep sea benthic formaniferaGeology, Vol. 22, No. 9, Sept. pp. 779-782GlobalK-T Boundary
DS1989-0459
1989
Galer, S.J.G.Galer, S.J.G., O'Nions, R.K.Chemical and isotopic studies of ultramafic inclusions from the San Carlos volcanic field, Arizona- a bearing on their petrogenesisJournal of Petrology, Vol. 30, No. 4, August pp. 1033-1064ArizonaGeochemistry, Geochronology, San Carlos
DS1991-0525
1991
Galer, S.J.G.Galer, S.J.G.Inter relationships between continental freeboard, tectonics and mantletemperatureEarth and Planetary Science Letters, Vol. 105, pp. 214-228GlobalSea-level, Archean tectonics
DS1992-1223
1992
Galer, S.J.G.Porcelli, 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
DS1993-0260
1993
Galer, S.J.G.Class, C., Goldstein, S.L., Galer, S.J.G.Young formation age of a mantle plume sourceNature, Vol. 362, No. 6422, April 22, pp. 715-721MantleHot spot, Plume, Geochronology
DS202004-0512
2020
Gales, E.Gales, E., Black, B., Elkins-Tanton, E.Carbonatites as a record of the carbon isotope composition of large igneous province outgassing.Earth and Planetary Science Letters, Vol. 535, 116076 11p. PdfRussia, Siberiacarbonatite

Abstract: Large igneous province (LIP) eruptions have been linked in some cases to major perturbations of Earth's carbon cycle. However, few observations directly constrain the isotopic composition of carbon released by LIP magmas because carbon isotopes fractionate during degassing, which hampers understanding of the relative roles of mantle versus crustal carbon reservoirs. Carbonatite magmatism associated with LIPs provides a unique window into the isotopic systematics of LIP carbon because the majority of carbon in carbonatites crystalizes rather than degassing. Although the volume of such carbonatites is small, they offer one of the few available constraints on the mantle carbon originally hosted in other more voluminous magma types. Here, we present new data for the Guli carbonatites in the Siberian Traps. In addition, we compile ~260 published measurements of from carbonatites related to the Deccan Traps and the Paraná-Etendeka. We find no evidence for magmas with carbon isotope ratios lighter than depleted mantle values of ‰ from any of these LIPs, though some carbonatites range to heavier . We attribute relatively heavy in some carbonatites to either slightly 13C-enriched domains in the mantle lithosphere or carbon isotope fractionation in deep, carbon-saturated LIP magma reservoirs. The absence of a light component in LIP magmas supports the view that lithospheric carbon reservoirs must be tapped during cases of LIP magmatism linked with sharp negative carbon isotope excursions and mass extinctions.
DS200912-0635
2009
Gali, S.Robles-Cruz, S.E., Watangua, M., Isidoro, l., Melgarejo, J.C., Gali, S., Olimpo, A.Contrasting compositions and textures of ilmenite in the Catoca kimberlite, Angola, and implications in exploration for diamond.Lithos, In press - available formatted 10p.Africa, AngolaDeposit - Catoca
DS201012-0632
2010
Gali, S.Robles-Cruz, S.E., Escayola, M., Melgarejo, J.C., Watangua, M., Gali, S., Goncalves, O.A., Jackson, S.Disclosed dat a from mantle xenoliths of Angolan kimberlites based on LA-ICP-MS analyses. Catoca and Cucumbi-79International Mineralogical Association meeting August Budapest, abstract p. 553.Africa, AngolaPetrology
DS201212-0113
2012
Gali, S.Castillo-Oliver, M., Gali, S., Gonscalves, A.O., Melgarejo, J.C.Use of indicator minerals in diamond exploration: a comparison between barren and fertile kimberlites in Angola.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, AngolaGeochemistry - KIMS
DS201212-0589
2009
Gali, S.Robles-Cruz, S., Lomba, A., Melgarejo, J-C., Gali, S., Olimpio Goncalves, A.The Cucumbi kimberlite, NE Angola: problems to discriminate fertile and barren kimberlites.Revist de la Sociedad de Mineralogia ( in english), pp. 159-160.Africa, AngolaDeposit - Cucumbi
DS201212-0590
2012
Gali, S.Robles-Cruz, S.E., Escayola, M., Jackson, S., Gali, S., Pervov, S., Watanga, M., Goncalves, A., Melgarejo, J.C.U-Pb SHRIMP geochronology of zircon from the Catoca kimberlite, Angola: implications for diamond exploration.Chemical Geology, Vol. 310-311, pp. 137-147.Africa, AngolaDeposit - Catoca
DS201604-0597
2016
Gali, S.Castilo-Oliver, M., Gali, S., Melgarejo, J.C., Griffin, W.L., Belousova, E., Pearson, N.J., Watangua, M., O'Reilly, S.Y.Trace element geochemistry and U-Pb dating of perovskite in kimberlites of the Lunda Norte province ( NE Angola): petrogenetic and tectonic implications.Chemical Geology, Vol. 426, pp. 118-134.Africa, AngolaGeochronology

Abstract: Perovskite (CaTiO3) has become a very useful mineral for dating kimberlite eruptions, as well as for constraining the compositional evolution of a kimberlitic magma and its source. Despite the undeniable potential of such an approach, no similar study had been done in Angola, the fourth largest diamond producer in Africa. Here we present the first work of in situ U-Pb geochronology and Sr-Nd isotope analyses of perovskite in six Angolan kimberlites, supported by a detailed petrographic and geochemical study of their perovskite populations. Four types of perovskite were identified, differing in texture, major- and trace-element composition, zoning patterns, type of alteration and the presence or absence of inclusions. Primary groundmass perovskite is classified either as anhedral, Na-, Nb- and LREE-poor perovskite (Ia); or euhedral, strongly zoned, Na-, Nb- and LREE-rich perovskite (Ib). Secondary perovskite occurs as reaction rims on ilmenite (IIa) or as high Nb (up to 10.6 wt% Nb2O5) perovskite rims on primary perovskite (IIb). The occurrence of these four types within the Mulepe kimberlites is interpreted as an evidence of a complex, multi-stage process that involved mingling of compositionally different melts. U-Pb dating of these perovskites yielded Lower Cretaceous ages for four of the studied kimberlites: Mulepe 1 (116.2 ± 6.5 Ma), Mulepe 2 (123.0 ± 3.6 Ma), Calonda (119.5 ± 4.3 Ma) and Cat115 (133 ± 10 Ma). Kimberlite magmatism occurred in NE Angola likely due to reactivation of deep-seated translithospheric faults (> 300 km) during the break-up of Gondwana. Sr-Nd isotope analyses of four of these kimberlites indicate that they are Group I kimberlites, which is consistent with the petrological observations.
DS201605-0819
2016
Gali, S.Castillo-Oliver, M., Gali, S., Melgarejo, J.C., Griffin, W.L., Belousova, E., Pearson, N.J., Watangua, M., O'Reilly, S.Y.Trace element geochemistry and U-Pb dating of perovskite in kimberlites of the Lunda Norte province ( NE Angola): petrogenetic and tectonic implications.Chemical Geology, Vol. 426, pp. 118-134.Africa, AngolaDeposit - Alto Cuilo

Abstract: Perovskite (CaTiO3) has become a very usefulmineral for dating kimberlite eruptions, aswell as for constraining the compositional evolution of a kimberlitic magma and its source. Despite the undeniable potential of such an approach, no similar study had been done in Angola, the fourth largest diamond producer in Africa. Here we present the firstwork of in situ U-Pb geochronology and Sr-Ndisotope analyses of perovskite in six Angolan kimberlites, supported by a detailed petrographic and geochemical study of their perovskite populations. Four types of perovskitewere identified, differing in texture,major- and trace-element composition, zoning patterns, type of alteration and the presence or absence of inclusions. Primary groundmass perovskite is classified either as anhedral, Na-, Nb- and LREE-poor perovskite (Ia); or euhedral, strongly zoned, Na-, Nb- and LREE-rich perovskite (Ib). Secondary perovskite occurs as reaction rims on ilmenite (IIa) or as high Nb (up to 10.6 wt% Nb2O5) perovskite rims on primary perovskite (IIb). The occurrence of these four types within the Mulepe kimberlites is interpreted as an evidence of a complex, multi-stage process that involved mingling of compositionally different melts. U-Pb dating of these perovskites yielded Lower Cretaceous ages for four of the studied kimberlites: Mulepe 1 (116.2±6.5Ma),Mulepe 2 (123.0±3.6Ma), Calonda (119.5±4.3 Ma) and Cat115 (133±10Ma). Kimberlite magmatism occurred in NE Angola likely due to reactivation of deep-seated translithospheric faults (N300 km) during the break-up of Gondwana. Sr-Nd isotope analyses of four of these kimberlites indicate that they are Group I kimberlites, which is consistent with the petrological observations.
DS201710-2263
2012
Gali, S.Robles-Cruz, S.E., Melgarejo, J.C., Gali, S., Escayola, M.Major and trace element compositions of indicator minerals that occur as macro and megacrysts, and of xenoliths, from kimberlites in northeastern Angola.Minerals NOTE Date, Vol. 2, pp. 318-337.Africa, Angoladeposits - Tchiuzo, Anomaly 116, Catoca, Alt Cuilo-4, Cuilo-63, Cucumbi-79.

Abstract: In this study, we compare the major- and trace-element compositions of olivine, garnet, and clinopyroxene that occur as single crystals (142 grains), with those derived from xenoliths (51 samples) from six kimberlites in the Lucapa area, northeastern Angola: Tchiuzo, Anomaly 116, Catoca, Alto Cuilo-4, Alto Cuilo-63 and Cucumbi-79. The samples were analyzed using electron probe microanalysis (EPMA) and laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS). The results suggest different paragenetic associations for these kimberlites in the Lucapa area. Compositional overlap in some of the macrocryst and mantle xenolith samples indicates a xenocrystic origin for some of those macrocrysts. The presence of mantle xenocrysts suggests the possibility of finding diamond. Geothermobarometric calculations were carried out using EPMA data from xenoliths by applying the program PTEXL.XLT. Additional well calibrated single-clinopyroxene thermobarometric calculations were also applied. Results indicate the underlying mantle experienced different equilibration conditions. Subsequent metasomatic enrichment events also support a hypothesis of different sources for the kimberlites. These findings contribute to a better understanding of the petrogenetic evolution of the kimberlites in northeastern Angola and have important implications for diamond exploration.
DS201711-2506
2017
Gali, S.Castillo-Oliver, M., Melgarejo, J.C., Gali, S., Pervov, V., Goncalves, A.O., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y.Use and misuse of Mg- and Mn- rich ilmenite in diamond exploration: a petrographic and trace element approach. Congo-Kasai cratonLithos, Vol. 292-293, pp. 348-363.Africa, Angoladeposit - CAT115, Tchiuzo

Abstract: Magnesian ilmenite is a common kimberlite indicator mineral, although its use in diamond exploration is still controversial. Complex crystallisation and replacement processes have been invoked to explain the wide compositional and textural ranges of ilmenite found in kimberlites. This work aims to shed light on these processes, as well as their implications for diamond exploration. Petrographic studies were combined for the first time with both major- and trace-element analyses to characterise the ilmenite populations found in xenoliths and xenocrysts in two Angolan kimberlites (Congo-Kasai craton). A multi-stage model describes the evolution of ilmenite in these pipes involving: i) crystallisation of ferric and Mg-rich ilmenite either as metasomatic phases or as megacrysts, both in crustal and in metasomatised mantle domains; ii) kimberlite entrainment and xenolith disaggregation producing at least two populations of ilmenite nodules differing in composition; iii) interaction of both types with the kimberlitic magma during eruption, leading to widespread replacement by Mg-rich ilmenite along grain boundaries and fractures. This process produced similar major-element compositions in ilmenites regardless of their primary (i.e., pre-kimberlitic) origin, although the original enrichment in HFSE (Zr, Hf, Ta, Nb) observed in Fe3 +-rich xenocrysts is preserved. Finally (iv) formation of secondary Mn-ilmenite by interaction with a fluid of carbonatitic affinity or by infiltration of a late hydrothermal fluid, followed in some cases by subsolidus alteration in an oxidising environment. The complexities of ilmenite genesis may lead to misinterpretation of the diamond potential of a kimberlite during the exploration stage if textural and trace-element information is disregarded. Secondary Mg-enrichment of ilmenite xenocrysts is common and is unrelated to reducing conditions that could favour diamond formation/preservation in the mantle. Similarly, Mn-rich ilmenite should be disregarded as a diamond indicator mineral, unless textural studies can prove its primary origin.
DS201906-1342
2019
Gali, S.Robles Cruz, S., Melgarejo, J.C., Gali, S.Revisiting the complexity of kimberlites from northeastern Angola.GAC/MAC annual Meeting, 1p. Abstract p. 166.Africa, Angoladeposit - Catoca

Abstract: The tectonic setting of northeastern Angola was influenced by the opening of the South Atlantic Ocean, which reactivated deep NE-SW-trending faults during the early Cretaceous. The new interpretation of a kimberlitic pulse during the middle of the Aptian and the Albian, which provides precise data on the age of a significant diamond-bearing kimberlite pulse in Angola, will be an important guide in future diamond exploration. These findings contribute to a better understanding of the petrogenetic evolution of the kimberlites in northeastern Angola and have important implications for diamond exploration. Six kimberlite pipes within the Lucapa structure in northeastern Angola have been investigated using major and trace element geochemistry of mantle xenoliths, macro- and megacrysts. Geothermobarometric calculations were carried out using xenoliths and well-calibrated single crystals of clinopyroxene. Geochronological and isotopic studies were also performed where there were samples available of sufficient quality. Results indicate that the underlying mantle experienced variable conditions of equilibration among the six sites. Subsequent metasomatic enrichment events also support a hypothesis of different sources for these kimberlites. The U/Th values suggest at least two different sources of zircon crystals from the Catoca suite. These different populations may reflect different sources of kimberlitic magma, with some of the grains produced in U- and Th-enriched metasomatized mantle units, an idea consistent with the two populations of zircon identified on the basis of their trace element compositions. This research shows the absence of fresh Mg-rich ilmenite in the Catoca kimberlite (one of the largest bodies of kimberlite in the world), as well as the occurrence of Fe3+-rich ilmenite, do not exclude the presence of diamond in the kimberlite. This is a new insight into the concept of ilmenite and diamond exploration and leads to the conclusion that compositional attributes must be evaluated in light of textural attributes.
DS1988-0588
1988
Galii, G.A.Rybalko, S.I., Galii, G.A., Gamarnik, M.Ya., et al.Electron optical studies of zircon from kimberlites.(Russian)Ontogeniya Mineralov I Teknol Mineral Kiev.(Russian), pp. 160-165RussiaMircoprobe, Zircon
DS201412-0261
2014
Galillou, E.Galillou, E., Post, J.E., Steele, A., Butler, J.E.Constrains on highly strained pink diamonds by high spatial resolution FTIR and Raman mapping.Geological Society of America Conference Vancouver Oct. 19-22, 1p. AbstractTechnologyPink diamond colour
DS200612-0421
2006
Galimov, E.Galimov, E., Kudin, A., Skorobogatskii, V., Plotnichenko, V., Bondarev, O., Zarubin, B., Strazdovskii, V., Aronin, A., Fisenko, A., Bykov, I., Barinov, A.Experimental corrobation of the synthesis of diamond in the cavitation process.Doklady Physical Chemistry, Vol. 49, 3, pp. 150-153.TechnologyDiamond synthesis
DS1970-0548
1972
Galimov, E.M.Kovalskiy, V.V., Galimov, E.M., et al.Isotopic Composition of Carbon from Colored Yakutian DiamondDoklady Academy of Science USSR, Earth Science Section., Vol. 203, No. 1-6, PP. 118-119.RussiaKimberlite, Geochronology, Genesis, Carbonado
DS1975-0747
1978
Galimov, E.M.Galimov, E.M., Kaminskiy, F.V., Ivanovskaya, I.N.Carbon Isotope Compositions of Diamonds from the Urals, Timan, Sayan, the Ukraine, and Elsewhere.Geochemistry International, Vol. 15, No. 2, PP. 11-18.RussiaBlank
DS1975-1024
1979
Galimov, E.M.Galimov, E.M., Klyuyev, Yu.A., et al.Correlation of Isotopic Distribution with Morphology and Lattice Structure in Diamonds from Yakutia Placers.Doklady Academy of Science USSR, Earth Science Section., Vol. 249, No. 1-6, PP. 153-156.Russia, YakutiaDiamond Morphology
DS1975-1042
1979
Galimov, E.M.Gurkina, G.A., Ivanovskaya, I.N., Kaminskiy, F.V., Galimov, E.M.The Distribution of Carbon Isotopes in Diamond Crystals.(russian)Geochemistry International (Geokhimiya)(Russian), Vol. 1979, No. 12, pp. 1897-1905RussiaBlank
DS1980-0134
1980
Galimov, E.M.Galimov, E.M., Ivanovskaya, I.N., et al.New Dat a on the Isotope Composition of Carbon in Diamonds from Various regions of the Soviet Union.Tsnigri, No. 153, PP. 19-29.RussiaBlank
DS1982-0308
1982
Galimov, E.M.Kaminskiy, F.V., Galimov, E.M., et al.Bort With Garnet from the Mir Pipe, YakutiaDoklady Academy of Science USSR, Earth Science Section., Vol. 256, No. 3, PP. 115-117.Russia, YakutiaCrystallcgraphy, Petrography
DS1984-0288
1984
Galimov, E.M.Galimov, E.M.13c/12c of Diamonds. Vertical Zonality of Diamond Formation InthelithosphereIn: Proceedings of the 27th. International Geological Congress held Moscow, August, Vol. 11, Geochemistry and Cosmochemistry, pp. 279-308GlobalDiamond Morphology
DS1984-0289
1984
Galimov, E.M.Galimov, E.M.Variations of Isotopic Composition of Diamond FormationGeokhemiya., No. 8, AUGUST PP. 1091-1118.RussiaBlank
DS1985-0209
1985
Galimov, E.M.Galimov, E.M.The relation between formation conditions and variations in isotope composition of diamondsGeochemistry International, Vol. 22, No. 1, pp. 118-142RussiaDiamond Morphology
DS1985-0210
1985
Galimov, E.M.Galimov, E.M.Some Evidence of Reality of the Cavitation Synthesis of Diamonds in Nature.Geockhimiya., No. 4, PP. 456-471. 66 REFS.RussiaDiamond Morphology, Crystallography
DS1985-0211
1985
Galimov, E.M.Galimov, E.M., Kaminsky, F.V., Kodina, L.A.New Dat a on Isotopic Composition of Carbon of CarbonadoGeochemistry International (Geokhimiya)., No. 5, MAY PP. 723-725.RussiaGeochemistry
DS1986-0260
1986
Galimov, E.M.Galimov, E.M.Some proofs of the reality of cavitational synthesis of diamonds in nature #2 (1986)Geochemistry International, No. 4, pp. 99-112RussiaDiamond morphology, geochemistry
DS1988-0233
1988
Galimov, E.M.Galimov, E.M.Carbon geochemistryGeochemistry International, Vol. pp. 94-110RussiaGeochemistry, Carbon
DS1988-0234
1988
Galimov, E.M.Galimov, E.M., Botkunov, A.I., Bannikova, L.A., et al.Isotopic composition of carbon from gas and bitumens of gas-liquid inclusions in garnet from the Mir kimberlite pipeDoklady Academy of Science USSR, Earth Science Section, Vol. 301, No. 4, July-Aug. pp. 184-185RussiaGeochronology, Carbon -Mir pipe
DS1989-0460
1989
Galimov, E.M.Galimov, E.M., Botkunov, A.I., Garanin, V.K.Carbon bearing fluid inclusions in olivine and garnet from the Udachnaya kimberlite pipe.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 7, pp. 1011-1015RussiaDiamond inclusions, Garnet analyses
DS1989-0461
1989
Galimov, E.M.Galimov, E.M., Botkunov, A.I., Garanin, V.K., Spasennykh, M. Yu.Carbon-containing fluid inclusions in garnet and olivine from Kimberlites of the Udachnaya pipe. (USSR)(Russian)Geochemistry International (Geokhimiya), (Russian), No. 7, pp. 1011-1015RussiaFluid inclusions, Garnet
DS1989-0462
1989
Galimov, E.M.Galimov, E.M., Kaminskiy, F.V., Maltsev, K.A., Sobolev, N.V.Relation of carbon isotopic composition with parageneses of mineral inclusions in diamonds in paired kimberlite pipes.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 5, pp. 754-758RussiaGeochronology - C Isotope, Diamond inclusions
DS1989-0463
1989
Galimov, E.M.Galimov, E.M., Sobolev, N.V., Yefimova, E.S.Isotopic composition of carbon of diamond bearing mineral inclusions From the northern Urals placers.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 9, pp. 1363-1370RussiaDiamond inclusions, Geochronology
DS1989-0464
1989
Galimov, E.M.Galimov, E.M., Soloviova, L.V., Belomestnykh, A.V.Carbon isotope composition of different forms of carbon in eclogite from Mir kimberlite pipe.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 305, No. 4, pp. 953-956RussiaEclogite, Geochronology
DS1989-0465
1989
Galimov, E.M.Galimov, E.M., Solovyeva, L.V., Belomesnyy, A.B.Isotopic composition of various forms of carbon in eclogite from kimberlite of the Mir pipeDoklady Academy of Sciences USSR, Earth Science Section, Vol. 305, No. 2, March-April pp. 204-206RussiaCarbon, Eclogite -Mir pipe
DS1989-0466
1989
Galimov, E.M.Galimov, E.M., Ukhanov, A.V.Nature of carbonate component of kimberlites.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 3, March pp. 337-348RussiaGeochemistry, Carbonate mineralogy
DS1989-0467
1989
Galimov, E.M.Galimov, E.M., Ukhanov, A.V.The carbonate component in kimberlitesGeochemistry International, Vol. 26, No. 10, pp. 14-23RussiaGeochronology, Carbonate-kimberlite
DS1989-1422
1989
Galimov, E.M.Sobolev, N.V., Galimov, E.M., Smith, C.B., Yefimova, E.S., MaltsevA comp study of the morphology, inclusions and C I composition of diamondsSoviet Geology and Geophysics, Vol. 30, No. 12, pp. 1-19AustraliaMicrodiamonds, Alluvial diamonds
DS1990-0505
1990
Galimov, E.M.Galimov, E.M., Botkunov, A.I., Garanin, V.K.Carbon bearing fluid inclusions in olivine and garnet from Udachnaya pipekimberlitesGeochemistry International, Vol. 27, No. 2, February pp. 87-90RussiaGeochronology, Carbon inclusions
DS1990-0506
1990
Galimov, E.M.Galimov, E.M., Kaminisky, F.V., Maltsev, K.A., Sobolev, N.V.The relation between delta 13 C and mineral inclusion assemblages in diamonds from paired kimberlite pipesGeochemistry International, Vol. 26, No. 12, pp. 134-137RussiaDiamond inclusions, carbon, Delta 13 C analyses
DS1990-0507
1990
Galimov, E.M.Galimov, E.M., Kuznetsov, V.P., Maltsev, K.A., Gorbachev, V.V.Isotopic composition of diamonds bearing the inclusions of diamond.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 7, July pp. 1033-1040RussiaDiamond inclusions, Geochronology
DS1990-0508
1990
Galimov, E.M.Galimov, E.M., Sobolev, N.V., Yefimova, E.S., Shemanina, Ye.I.Carbon isotope composition of inclusion bearing diamonds from north UralplacersGeochemistry Int, Vol. 27, No. 4, pp. 131-138RussiaGeochronology CI, Placers
DS1990-0509
1990
Galimov, E.M.Galimov, E.M., Solovyeva, L.V., Belomestnykh, A.V.Carbon isotope composition of metasomatized mantle rocksGeochemistry International, Vol. 26, No. 11, April pp. 38-43RussiaMantle, Geochronology
DS1991-0526
1991
Galimov, E.M.Galimov, E.M.Isotope fractionation related to kimberlite magmatism and diamond formation #1Geochimica et Cosmochimica Acta, Vol. 55, pp. 1697-1708GlobalKimberlite magaM., Diamond genesis
DS1991-0527
1991
Galimov, E.M.Galimov, E.M.Isotope fractionation related to kimberlite magmatism and diamond formation #2Proceedings of Fifth International Kimberlite Conference held Araxa June, pp. 502-504RussiaGeochronology, Diamond genesis
DS1991-0528
1991
Galimov, E.M.Galimov, E.M., Kuznetsova, V.P., Maltsev, K.A., Gorbachev, V.V.Isotope composition of diamonds containing diamond inclusionsGeochemistry International, Vol. 28, No. 1, pp. 115-121RussiaGeochronology, Diamond inclusions
DS1991-1042
1991
Galimov, E.M.Maltsev, K.A., Galimov, E.M.Isotope distribution in hydrogen of diamondDoklady Academy of Science USSR, Earth Science Section, Vol. 308, No. 5, pp. 229-230RussiaDiamond inclusions, Hydrogen
DS1993-0859
1993
Galimov, E.M.Krot, A.N., Poskukojovsky, T.V., Guseva, E.V., Galimov, E.M., Botkunov, A.I. et.Genesis of the garnets containing hydrocarbon inclusions (Mir kimberlitepipe). (Russian)Geochemistry International (Geokhimiya), (Russian), No. 6, June pp. 891-899RussiaGeochemistry -garnets, Deposit -Mir
DS1993-1498
1993
Galimov, E.M.Sobolev, N.V., Galimov, E.M., Efimova, E.S., Sobolev, E.V.Crystalline inclusions, isotopes carbon, nitrogen centers in diamonds, features of garnet from Madjgawan.Russian Geology and Geophysics, Vol. 34, No. 12, pp. 77-83.IndiaDiamond inclusions, Deposit -Madjgawan
DS1994-0562
1994
Galimov, E.M.Galimov, E.M., et al.The carbon isotope composition of north Chin a platform diamonds.(Russian)Doklady Academy of Sciences Nauk., (Russian), Vol. 337, No. 4, August pp. 467-468.ChinaGeochronology, Diamond, isotope -carbon
DS1994-0563
1994
Galimov, E.M.Galimov, E.M., Zakharch, O.D., Maltsev, K.A., Makhin, A.I.The isotopic composition of carbon in diamonds from the kimberlitic pipe sat Archangelsk.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 1, pp. 67-74.Russia, Yakutia, ArkangelskGeochronology, Diamond inclusions -carbon
DS1994-0564
1994
Galimov, E.M.Galimov, E.M., Zakharchenko, K.A., et al.Carbon isotope composition of diamonds from Arkangel region kimberlitepipes.Geochemistry International, Vol. 31, No. 8, pp. 71-78.Russia, ArkangelskDiamond geochronology, Deposit -Arkangel
DS1995-0575
1995
Galimov, E.M.Galimov, E.M., Bao Yannan, K.A., Maltsev, K.A., SmirnovaIsotopic composition of diamonds from the North Chinese PlatformDoklady Academy of Sciences Acad. Science Russia, Vol. 331A, No. 6, June pp. 189-192.ChinaGeochronology, Diamonds
DS1998-0461
1998
Galimov, E.M.Galimov, E.M.Growth of the earth's core as a source of its internal energy and a Factor of mantle redox evolution.Geochemistry International, Vol. 36, No. 8, Aug. 1, pp. 673-6.MantleRedox
DS1998-0462
1998
Galimov, E.M.Galimov, E.M., Mirononv, A.G., Shiryaev, A.A.Origin of carbon in Diamondiferous carbonized ultrabasites at the EasternSayan.Doklady Academy of Sciences, Vol. 363A, No. 9, Nov-Dec. pp. 1304-6.Russia, SayanMetamorphic rocks, Carbon, diamond
DS1998-1344
1998
Galimov, E.M.Shiryaev, A.A., Galimov, E.M., Sobolev, N.V., KolesovTrace elements in inclusion free diamonds from Venezuela and Arkhangelskdeposits.7th International Kimberlite Conference Abstract, pp. 811-13.Russia, Kola, VenezuelaDiamond formation, genesis, Mineral inclusions
DS2003-1269
2003
Galimov, E.M.Shiryaev, A., Izraeli, E.S., Hauri, E.., Galimov, E.M., Navon, O.Fluid inclusions in Brazilian coated diamonds8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractBrazilDiamonds - inclusions
DS200512-0309
2005
Galimov, E.M.Galimov, E.M.Redox evolution of the Earth caused by a multi stage formation of its core.Earth and Planetary Science Letters, Vol. 233, 3-4, May 15, pp. 263-276.MantleGeothermometry, core-mantle boundary
DS200612-0135
2006
Galimov, E.M.Bibikova, E.V., Galimov, E.M.Time and geodynamic constraints on the formation and evolution of the early Earth's crust.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.MantleGeodynamics
DS200812-0380
2008
Galimov, E.M.Galimov, E.M., Palazhchenko, O.V., Verichev, E.M., Garanin, V.K., Golovin, N.N.Carbon isotope composition of diamonds from the Archangelsk diamond province.Geochemistry International, Vol. 46, 10, pp. 961-970.Russia, Archangel, Kola PeninsulaDiamond chemistry
DS200812-0596
2008
Galimov, E.M.Kostitsyn, Y.A., Bibikova, E.V., Galimov, E.M.Finite speed of mantle homogenization and Hf W assessments of the Earth's core age.Goldschmidt Conference 2008, Abstract p.A493.MantleGeochronology
DS200812-0839
2008
Galimov, E.M.Palazhchenko, O.V., Garanin, V.K., Galimov, E.M.Isotope and mineralogical study of diamonds from northwestern Russia.Goldschmidt Conference 2008, Abstract p.A718.Russia, Kola Peninsula, ArchangelDeposit - Lomonosov, Grib
DS200912-0239
2009
Galimov, E.M.Galimov, E.M.Advances in geochemistry during the last four decades: a personal perspective.Applied Geochemistry, Vol. 24, 6, pp. 1048-1051.TechnologyGeochemistry
DS201608-1404
2016
Galimov, E.M.Galimov, E.M., Sevastyanov, V.S., Karpova, G.A., Shilobreeva, S.N., Maksimov, A.P.Microcrystalline diamonds in the oceanic lithosphere and their nature. MicrodiamondsDoklady Earth Sciences, Vol. 469, 1, pp. 670-673.RussiaTolbachik Volcano

Abstract: The carbon isotope composition of microdiamonds found in products of the Tolbachik Volcano eruption, Kamchatka (porous lavas and ash), was studied. The isotope composition of microdiamonds (with an average value of d13C =-25.05‰) is close to that of microsized carbon particles in lavas (from-28.9 to-25.3‰). The general peculiarities of the diamond-forming environment include (1) no evidence for high pressure in the medium; (2) a reduced environment; and (3) mineralogical evidence for the presence of a fluid. The geochemical data characterizing the type of diamonds studied allow us to suggest that they were formed in accordance with the mechanism of diamond synthesis during cavitation in a rapidly migrating fluid, which was suggested by E.M. Galimov.
DS202005-0731
2020
Galimov, E.M.Galimov, E.M., Kaminsky, F.V., Shilobreeva, S.N., Sevastyanov, V.S., Voropaev, S.A., Khachatryan, G.K., Wirth, R., Schreiber, A., Saraykin, V.V., Karpov, G.A., Anikin, L.P.Enigmatic diamonds from the Tolbachik volcano, Kamchatka.American Mineralogist, Vol. 105, pp. 498-509. pdfRussiadeposit - Tolbachik

Abstract: Approximately 700 diamond crystals were identified in volcanic (mainly pyroclastic) rocks of the Tolbachik volcano, Kamchatka, Russia. They were studied with the use of SIMS, scanning and transmission electron microscopy, and utilization of electron energy loss spectroscopy and electron diffraction. Diamonds have cube-octahedral shape and extremely homogeneous internal structure. Two groups of impurity elements are distinguished by their distribution within the diamond. First group, N and H, the most common structural impurities in diamond, are distributed homogeneously. All other elements observed (Cl, F, O, S, Si, Al, Ca, and K) form local concentrations, implying the existence of inclusions, causing high concentrations of these elements. Most elements have concentrations 3-4 orders of magnitude less than chondritic values. Besides N and H, Si, F, Cl, and Na are relatively enriched because they are concentrated in micro- and nanoinclusions in diamond. Mineral inclusions in the studied diamonds are 70-450 nm in size, round- or oval-shaped. They are represented by two mineral groups: Mn-Ni alloys and silicides, with a wide range of concentrations for each group. Alloys vary in stoichiometry from MnNi to Mn2Ni, with a minor admixture of Si from 0 to 5.20-5.60 at%. Silicides, usually coexisting with alloys, vary in composition from (Mn,Ni)4Si to (Mn,Ni)5Si2 and Mn5Si2, and further to MnSi, forming pure Mn-silicides. Mineral inclusions have nanometer-sized bubbles that contain a fluid or a gas phase (F and O). Carbon isotopic compositions in diamonds vary from -21 to -29‰ d13CVPDB (avg. = -25.4). Nitrogen isotopic compositions in diamond from Tolbachik volcano are from -2.32 to -2.58‰ d15NAir. Geological, geochemical, and mineralogical data confirm the natural origin of studied Tolbachik diamonds from volcanic gases during the explosive stage of the eruption.
DS200712-0872
2007
Galindo, C.Rapela, C.W., Pankhurst, R.J., Casquet, C., Fanning, C.M., Baldor Casado, E.G., Galindo, C., DahlquistThe Rio de la Plat a craton and the assembly of SW Gondwana.Earth Science Reviews, In press availableSouth America, BrazilTectonics
DS200712-0873
2007
Galindo, C.Rapela, C.W., Pankhurts, R.J., Casquet, C., Fanning, C.M., Baldo, E.G., Gonzalez-Casado, J.M., Galindo, C., Dahlquist, J.The Rio de la Plate craton and the assembly of SW Gondwana.Earth Science Reviews, Vol. 83, 1-2, pp. 49-82.South America, BrazilCraton, tectonics
DS1985-0212
1985
Galinov, E.M.Galinov, E.M., Kaminskiy, F.V., Kodina, L.A.New Dat a on Carbonado Carbon Isotope CompositionsGeochemistry International, Vol. 22, No. 9, pp. 18-21Russia, BrazilLonsdaleite, Morphology
DS1975-0281
1976
Galipeau, J.M.Galipeau, J.M.Petrochemistry of the Virginia Dale Ring Dike ComplexMsc. Thesis, University North Carolina., United States, Wyoming, Colorado, State Line, Rocky MountainsRegional Studies
DS1975-1025
1979
Galipeau, J.M.Galipeau, J.M., Ragland, P.C.Whole Rock Chemical Constraints on the Origin of the Virginia Dale Ring Dike Complex.Geochemical Journal, Vol. 13, No. 5, NOVEMBER PP. 207-216.United States, Colorado, Wyoming, State Line, Rocky MountainsGeochemistry
DS201802-0245
2017
Galkin, A.S.Kiselev, G.P., Yakovlev, E.Yu., Druzhinin, S.V., Galkin, A.S.Distribution of radioactive isotopes in rock and ore of Arkhanelskava pipe from the Arkhanelsk diamond province.Geology of Ore Deposits, Vol. 59, pp. 391-406.Russia, Archangeldeposit - Arkhangelskaya

Abstract: The contents of radioactive elements and the uranium isotopic composition of kimberlite in the Arkhangelskaya pipe at the M.V. Lomonosov deposit and of nearby country rocks have been studied. A surplus of 234U isotope has been established in rocks from the near-pipe space. The high ? = 234U/238U ratio is controlled by the geological structure of the near-pipe space. A nonequilibrium uranium halo reaches two pipe diameters in size and can be regarded as a local ore guide for kimberlite discovery. The rocks in the nearpipe space are also characterized by elevated or anomalous U, Th, and K contents with respect to the background.
DS1990-0419
1990
Galkin, V.M.Doroshev, A.M., Galkin, V.M., Turkin, A.I., Kalinin, A.A.Thermal expansion of garnets of pyrope grossularite and pyrope Knorringiteseries.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 1, January 1990, pp. 152-155RussiaGarnet-pyrope, Geochemistry
DS1990-0420
1990
Galkin, V.M.Doroshev, A.M., Galkin, V.M., Turkin, A.I., Kalinin, A.A.Thermal expansion in the pyrope-grossular and pyrope-knorringite garnetseriesGeochemistry International, Vol. 27, No. 8, pp. 144-149RussiaMineralogy, Pyrope
DS201012-0140
2010
Gall, L.De Hoog, J.C.M., Gall, L., Cornell, D.H.Trace element geochemistry of mantle olivine and application to mantle petrogenesis and geothermometry.Chemical Geology, In press available formatted 20p.MantleGeobarometry
DS1992-0508
1992
Gall, Q.Gall, Q.Precambrian paleosols in CanadaCanadian Journal of Earth Sciences, Vol. 29, No. 12, December pp. 2530-2536Northwest Territories, Ontario, Manitoba, SaskatchewanWeathering, Laterites, paleosols
DS1992-0509
1992
Gall, Q.Gall, Q.Precambrian paleosols in CanadaCanadian Journal of Earth Sciences, Vol.29, pp. 2350-56.CanadaPaleosols - location list, Structure - microstructures
DS1994-0565
1994
Gall, Q.Gall, Q.The Proterozoic The lon paleosol, Northwest Territories, CanadaPrecambrian Research, Vol. 68, No. 1/2, June pp. 115-138Northwest TerritoriesProterozoic, Thelon paleosol, sedimentary
DS2003-0435
2003
Gall, S.Gall, S.The Bushmen of the KalahariThe Ecologist, Vol. 33, No. 7, pp. 28-31.BotswanaHistory
DS200412-0602
2003
Gall, S.Gall, S.The Bushmen of the Kalahari.The Ecologist, Vol. 33, no. 7, pp. 28-31.Africa, BotswanaHistory
DS201212-0591
2012
Galla, S.Robles-Cruz, S.E., Galla, S., Escayoblab, M., Melgarejoa, J.C.Heterogeneous mantle beneath the Lunda area in Angola.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, AngolaDeposit - Lunda area
DS201809-2100
2018
Gallacher, R.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.
DS201905-1056
2019
Gallacher, R.Lavayssiere, A., Drooff, C., Ebinger, C., Gallacher, R., Illsley-Kemp, F., Finnigan, Oliva, S.J., Keir, D.Deep extent and kinematics of faulting in the southern Tanganyika Rift, Africa.Tectonics, Vol. 38, 3, pp. 842-862.Africarifting

Abstract: Unusually deep earthquakes occur beneath rift segments with and without surface expressions of magmatism in the East African Rift system. The Tanganyika rift is part of the Western rift and has no surface evidence of magmatism. The TANG14 array was deployed in the southern Tanganyika rift, where earthquakes of magnitude up to 7.4 have occurred, to probe crust and upper mantle structure and evaluate fault kinematics. Four hundred seventy-four earthquakes detected between June 2014 and September 2015 are located using a new regional velocity model. The precise locations, magnitudes, and source mechanisms of local and teleseismic earthquakes are used to determine seismogenic layer thickness, delineate active faults, evaluate regional extension direction, and evaluate kinematics of border faults. The active faults span more than 350 km with deep normal faults transecting the thick Bangweulu craton, indicating a wide plate boundary zone. The seismogenic layer thickness is 42 km, spanning the entire crust beneath the rift basins and their uplifted flanks. Earthquakes in the upper mantle are also detected. Deep earthquakes with steep nodal planes occur along subsurface projections of Tanganyika and Rukwa border faults, indicating that large offset (=5 km) faults penetrate to the base of the crust, and are the current locus of strain. The focal mechanisms, continuous depth distribution, and correlation with mapped structures indicate that steep, deep border faults maintain a half-graben morphology over at least 12 Myr of basin evolution. Fault scaling based on our results suggests that M > 7 earthquakes along Tanganyika border faults are possible.
DS1998-0172
1998
GallagherBrown, R.W., Gallagher, Griffin, Ryan, De Wit, BeltonKimberlites, accelerated erosion and evolution of the lithospheric mantle beneath Kaapvaal - mid-Cretaceous..7th International Kimberlite Conference Abstract, pp. 105-107.South AfricaHeat flow data, uplift, Kaapvaal Craton
DS1993-0920
1993
Gallagher, A.J.Livo, K.E., Gallagher, A.J.REMAPP-PC remote sensing image processing software for MS-DIS personalcomputers, version 2.00/United States Geological Survey (USGS) Open File, No. 91-0449 A-G each disc $ 6.00 = $ 42.00GlobalComputer, Program -REMAPP-PC.
DS1992-0510
1992
Gallagher, K.Gallagher, K., Hawkesworth, C.Dehydration melting and the generation of continental flood basaltsNature, Vol. 358, no 6381, July 2, pp. 57-59Brazil, NamibiaFlood basalts, Dehydration
DS1993-0643
1993
Gallagher, K.Hawkesworth, C.J., Gallagher, K., et al.Mantle hotspots, plumes and regional tectonics as causes of intraplatemagmatism.Terra Nova, Vol. 5, No. 6, pp. 552-559.MantleHot spots, subduction, melting, Tectonics
DS1993-0644
1993
Gallagher, K.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
Gallagher, K.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
DS1994-0218
1994
Gallagher, K.Brown, R., Gallagher, K., Duane, M.A quantitative assessment of the effects of magmatism on the thermal history of the Karoo sediment sequenceJournal of African Earth Sciences, Vol. 18, No. 3, April pp. 245-254South AfricaMagmatism, Karoo sedimentology
DS1994-0219
1994
Gallagher, K.Brown, R., Gallagher, K., Duane, M.A quantitative assessment of effects of magmatism on the thermal history Of the Karoo sedimentary sequenceJourn. African Earth Sciences, Vol. 18, No. 3, pp. 227-243South AfricaMagmatism, Paleotemperatures
DS1994-0566
1994
Gallagher, K.Gallagher, K., Hawkesworth, C.Mantle plumes, continental magmatism and asymmetry in the South AtlanticEarth and Planetary Science Letters, Vol. 123, pp. 105-17.GlobalPlumes, Magmatism
DS1994-0743
1994
Gallagher, K.Hawkesworth, C., Gallagher, K., Turner, S.Causes of melt generation in the sub-continental mantleMineralogical Magazine, Vol. 58A, pp. 394-395. AbstractMantleMantle plumes, Magma
DS1994-0745
1994
Gallagher, K.Hawkesworth, 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
DS1996-0182
1996
Gallagher, K.Brown, R., Gallagher, K., De Wit, M., Gleadow, A.The Cratonic conundrum: does old+cold+thick=stable?Australia Nat. University of Diamond Workshop July 29, 30. abstract, 1p.South Africa, BrazilCraton, Paleotemperatures
DS2000-0394
2000
Gallagher, K.Hawkesworth, C.J., Gallagher, K., Turner, S.P.Tectonic controls on magmatism associated with continental break up: an example from Parana-Etendeka.Earth and Planetary Science Letters, Vol. 179, No. 2, June 30, pp. 335-50.BrazilTectonics, Magmatism
DS2001-0913
2001
Gallagher, K.Petford, N., Gallagher, K.Partial melting of mafic amphibilitic lower crust by periodic influx of basaltic magmaEarth and Planetary Science Letters, Vol. 193, No. 3-4, pp.483-99.MantleMagmatism
DS2002-0870
2002
Gallagher, K.Kohn, B.P., Gleadow, A.J.W., Brown, R.W., Gallagher, K., O'Sullivan, P.B.Shaping the Australian crust over the last 300 million years: insights from fission trackAustralian Journal of Earth Sciences, Vol. 49,4,August pp. 697-718.AustraliaTectonics, Geothermometry
DS200912-0118
2009
Gallagher, K.Cobden, L., Goes, S., Ravenna, M., Styles, E., Cammarano, F., Gallagher, K., Connolly, J.Thermochemical interpretation of 1-D seismic dat a for the lower mantle: the significance of nonadiabiatic thermal gradients and compositional heterogeneity.Journal of Geophysical Research, Vol. 114, B 11, B11309MantleGeophysics - seismics. geothermometry
DS201502-0046
2014
Gallagher, K.Brown, R., Summerfield, M., Gleadow, A., Gallagher, K., Carter, A., Beucher, R., Wildman, M.Intracontinental deformation in southern Africa during the Late Cretaceous.Journal of African Earth Sciences, Vol. 100, pp. 20-41.Africa, NamibiaGeothermometry

Abstract: Intracontinental deformation accommodated along major lithospheric scale shear zone systems and within associated extensional basins has been well documented within West, Central and East Africa during the Late Cretaceous. The nature of this deformation has been established by studies of the tectonic architecture of sedimentary basins preserved in this part of Africa. In southern Africa, where the post break-up history has been dominated by major erosion, little evidence for post-break-up tectonics has been preserved in the onshore geology. Here we present the results of 38 new apatite fission track analyses from the Damara region of northern Namibia and integrate these new data with our previous results that were focused on specific regions or sections only to comprehensively document the thermo-tectonic history of this region since continental break-up in the Early Cretaceous. The apatite fission track ages range from 449 ± 20 Ma to 59 ± 3 Ma, with mean confined track lengths between 14.61 ± 0.1 µm (SD 0.95 µm) to 10.83 ± 0.33 µm (SD 2.84 µm). The youngest ages (c. 80–60 Ma) yield the longest mean track lengths, and combined with their spatial distribution, indicate major cooling during the latest Cretaceous. A simple numerical thermal model is used to demonstrate that this cooling is consistent with the combined effects of heating caused by magmatic underplating, related to the Paraná-Etendeka continental flood volcanism associated with rifting and the opening of the South Atlantic, and enhanced erosion caused by major reactivation of major lithospheric structures within southern Africa during a key period of plate kinematic change that occurred in the South Atlantic and SW Indian ocean basins between 87 and 56 Ma. This phase of intraplate tectonism in northern Namibia, focused in discrete structurally defined zones, is coeval with similar phases elsewhere in Africa and suggests some form of trans-continental linkage between these lithospheric zones.
DS1960-0344
1963
Gallagher, M.J.Gallagher, M.J.Lamprophyre Dykes from ArgylMineralogical Magazine., Vol. 33, PP. 415-430.Australia, Western AustraliaRelated Rocks
DS1994-0839
1994
Gallagher, R.Jaques, A.L., Wyborn, L.A.L., Gallagher, R.The role of geographic information systems, empirical modelling and expert systems in metallogenic research.Geological Society of Australia Abstracts, No. 37, p. 196-7.Australia, Western AustraliaGIS, Metallogeny, alkaline rocks
DS201212-0226
2012
Gallagher, R.J.Gallagher, R.J., Bastow, I.D.Receiver function constraints on crustal structure in Cameroon: implications for basement development and magmatism along the Cameroon Volcanic Line.Tectonics, in preparationAfrica, CameroonGeophysics - seismics
DS201312-0290
2013
Gallagher, W.Gallagher, W.Where have all the miners gone? Aboriginals are now masters of Canada's resource agenda says new book…. Bill Gallagher Resource rules: fortune and folly on Canada's road to resources.Canadian Mining Journal, Feb/March pp. 50-53. Gallagher's book is self published.CanadaCSR
DS1950-0026
1950
Gallagher, W.S.Gallagher, W.S., Kuttner, R.The Application of Long Hole Drilling to Diamond MiningAssociation MINE MANAGERS TRANSVAAL Circular, No. 8/50, 42P.South AfricaMining
DS1960-0045
1960
Gallagher, W.S.Gallagher, W.S.Mining Blue Ground at de BeersEngineering and Mining Journal, Vol. 161, PP. 92-102.South AfricaMining Methods, Recovery
DS1960-0046
1960
Gallagher, W.S.Gallagher, W.S., Loftus, W.K.B.Block Caving Practice at de Beers Consolidated Mines LimitedSouth African Institute of Mining and Metallurgy. Journal, Vol. 61, APRIL, PP. 405-429.South AfricaMining Methods, Recovery, Evaluation, Diamond, Kimberlite Pipes
DS1960-0047
1960
Gallagher, W.S.Gallagher, W.S., Sandilands, J.S., Howell, T.V.Native Administration in the Kimberley Diamond MinesSouth African Institute of Mining and Metallurgy. Journal, Vol. 60, No. 5, PP. 500-502.South AfricaPolitics, Mining Methods, Recovery
DS1960-0242
1962
Gallagher, W.S.Gallagher, W.S., Loftus, W.K.B.Yielding Arches for Support of Block Cave Scraper DriftsAssociation MINE MANAGERS STH. AFR. 1960/1961, PP. 439-450.South AfricaMining Methods
DS2002-1294
2002
Gallagherm K.Raab, M.J., Brown, R.W., Gallagherm K., Carter, A., Weber, K.Late Cretaceous reactivation of major crustal shear zones in northern Namibia: constraints from apatite fission track analysis.Tectonophysics, Vol. 349, No. 1-4, pp.75-92.NamibiaGeochronology, Tectonics
DS200712-0343
2007
Galland, O.Galland, O., Cobbold, P.R., De Bremond d'Ars, J., Hallot, E.Rise and emplacement of magma during horizontal shortening of the brittle crust: insights from experiments.Journal of Geophysical Research, Vol. 112, B6 B06402MantleMagmatism
DS201112-0342
2011
Gallardo, L.A.Gallardo, L.A., Meju, M.A.Structure coupled multiphysics imaging in geophysical sciences.Reviews of Geophysics, Vol. 49, 1, RG1003TechnologyGeophysics - not specific to diamonds
DS2000-0137
2000
Gallart, J.Carbonell, R., Gallart, J., Knapp, J.Seismic wide angle constraints on the crust of the southern UralsJournal of Geophysical Research, Vol. 105, No. 6, June 10, pp. 13755-78.Russia, Urals, KolaGeophysics - seismics
DS201312-0556
2013
Gallart, J.Luciana, B., Schimmel, M., Gallart, J., Morales, J.Studying the 410-km and 660-km discontinuities beneath Spain and Morocco through detection of P-to-s conversions.Geophysical Journal International, Vol. 194, 2, pp. 920-935.Europe, Spain, Africa, MoroccoGeophysics -
DS2002-0706
2002
GallasteguiHeredia, N., Rodiguez Fernandez, L.R., GallasteguiGeological setting of the Argentine frontal Cordillera in the flat slab segment 30 - 31)Journal of South American Earth Sciences, Vol.15,1,Apr.pp.79-99.Chile, AndesSubduction, Slab
DS201412-0412
2014
Gallego, A.Ito, G., Dunn, R.L.A., Wolfe, C.J., Gallego, A., Fu, Y.Seismic anisotropy and shear wave splitting associated with mantle plume-plate interactions.Journal of Geophysical Research, Vol. 119, no. 6, pp. 4923-4937.MantleGeophysics - seismics
DS201112-0173
2011
Gallet, S.Chauvel, C., Garcon, M., Arndt, N.T., Gallet, S., Jahn, B.M.Average Nd hf isotopic compositions and model age of the upper continental crust.Goldschmidt Conference 2011, abstract p.646.Africa, South AfricaBeach placers
DS1998-1505
1998
Gallet, Y.Valet, J.P., Gallet, Y.Paleomagnetism: ancient inclinationNature, Vol. 396, No. 6709, Nov. 26, pp. 315-6.MantleGeophysics - paleomagnetics
DS2000-0309
2000
Gallet, Y.Gallet, Y., Pavlov, V.E., Petrov, P.Y.Late Mesoproterozoic magnetostratigraphic results from Siberia: Paleogeographic implications and magnetics ..Journal of Geophysical Research, Vol.105, No.7, July 10, pp.16481-Russia, SiberiaGeophysics - magnetics
DS2002-1234
2002
Gallet, Y.Pavlov, V.E., Gallet, Y., Petrov, P.Y., Zhuravlev, D.Z., Shatsillo, A.V.The Ui Group and Late Riphean sills in the Uchur Maya area: isotopic andGeotectonics, Vol. 36,4,pp. 278-92.GondwanaGeochronology
DS201412-0522
2014
Gallet, Y.Livermore, P.W., Fournier, A., Gallet, Y.Core-flow constraints on extreme archeomagnetic intensity changes.Earth and Planetary Science Letters, Vol. 387, pp. 145-156.MantleGeophysics - magnetics
DS1989-0367
1989
Galley, A.Dostal, J., Jackson, G.D., Galley, A.Geochemistry of Neohelikian Nauyat plateau basalts, Borden rift basin, northwestern Baffin Island.Canadian Journal of Earth Sciences, Vol. 26, pp. 2214-23.Northwest Territories, Baffin IslandBasalts
DS1997-0041
1997
Galli, A.Armstrong, M., Galli, A.Option pricing: a new approach to valuing mining projectsThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 90, No. 1009, April pp. 37-44GlobalEconomics, geostatistics, valuation, discoveries, Option pricing, evaluation
DS201904-0738
2019
Galli, A.Galli, A., Grassi, D., Sartori, G., Gianola, O., Burg, J-P., Schmidt, M.W.Jurassic carbonatite and alkaline magmatism in the Ivrea zone ( European Alps) related to the breakup of Pangea.Geology, Vol. 47, 3, pp. 199-202..Europecarbonatite

Abstract: We report on pipe-like bodies and dikes of carbonate rocks related to sodic alkaline intrusions and amphibole mantle peridotites in the Ivrea zone (European Southern Alps). The carbonate rocks have bulk trace-element concentrations typical of low-rare earth element carbonatites interpreted as cumulates of carbonatite melts. Faintly zoned zircons from these carbonate rocks contain calcite inclusions and have trace-element compositions akin to those of carbonatite zircons. Laser ablation-inductively coupled plasma-mass spectrometry U-Pb zircon dating yields concordant ages of 187 ± 2.4 and 192 ± 2.5 Ma, coeval with sodic alkaline magmatism in the Ivrea zone. Cross-cutting relations, ages, as well as bulk and zircon geochemistry indicate that the carbonate rocks are carbonatites, the first ones reported from the Alps. Carbonatites and alkaline intrusions are comagmatic and were emplaced in the nascent passive margin of Adria during the Early Jurassic breakup of Pangea. Extension caused partial melting of amphibole-rich mantle domains, yielding sodic alkaline magmas whose fractionation led to carbonatite-silicate melt immiscibility. Similar occurrences in other rifts suggest that small-scale, sodic and CO2-rich alkaline magmatism is a typical result of extension and decompression-driven reactivation of amphibole-bearing lithospheric mantle during passive continental breakup and the evolution of magma-poor rifts.
DS1990-0510
1990
Galli, G.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
DS1991-0529
1991
Galli, G.Galli, G.Diamond melting and liquid carbonPhys. Scr, Vol. T39, pp. 148=150. #GV573GlobalExperimental petrology, Diamond melting
DS1991-0530
1991
Gallo, M.B.M.Gallo, M.B.M.The Romaria diamond bearing Cretaceous conglomerateFifth International Kimberlite Conferences Field Excursion Guidebook, Servico Geologico do Brasil (CPRM) Special, pp. 37-44BrazilConglomerate, Romaria
DS1900-0059
1901
Gallois, L.Gallois, L.La Geologie du Transvaal D'apres MolengraaffAnnual GEOL. PARIS, Vol. 10, PP. 450-453.Africa, South AfricaGeology
DS200812-0805
2008
Galloway, M.Nowicki, T., Helman, C., Gurney, J., Van Coller, B., Galloway, M., Smith, C., Mukodzani, B.Optimizing kimberlite evaluation programs by integrating geological, mineralogical and geophysical data.GSSA-SEG Meeting Held July, Johannesburg, 19 Power point slidesTechnologyEvaluation
DS200812-0806
2008
Galloway, M.Nowicki, T., Hetman, C.J., Gurney, J., Van Collar, B., Galloway, M., Mukodzani, B.Optimizing kimberlite evaluation programs by integrating geological, mineralogical and geophysical data.Northwest Territories Geoscience Office, p. 46-47. abstractTechnologyBrief overview - evaluation
DS200912-0240
2009
Galloway, M.Galloway, M., Nowicki, T., Van Coller, B., Mukodzani, B., Siemens, K., Hetman, C., Webb, K., Gurney, J.Constraining kimberlite geology through integration of geophysical, geological and geochemical methods: a case study of the Mothae kimberlite, northern Lesotho.Lithos, In press - available 47p.Africa, LesothoDeposit - Mothae
DS201806-1224
2018
Galmiche, A.Galmiche, A.Is space our next diamond resource?Gems&Jewellery www.gem-a-com, Spring, pp. 32-35.Technologyasteroids
DS1995-0576
1995
Galoisy, L.Galoisy, L., Calas, G., Brown, G.E.Intracrystalline distribution of nickel in San Carlos olivine: an EXAFS studyAmerican Mineralogist, Vol. 80, No. 9-10, Sept, Oct pp. 1089-1092.ArizonaPeridotite
DS200712-0497
2007
Galoisy, L.Juhin, A., Cabaret, D., Galoisy, L., Hazemann, J-L., Calas, G.First principles investigation of trace element in corporation in minerals: the case of Cr3+ in spinel and pyrope garnet.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.166-167.TechnologyGarnet mineralogy
DS200712-0498
2007
Galoisy, L.Juhin, A., Cabaret, D., Galoisy, L., Hazemann, J-L., Calas, G.First principles investigation of trace element in corporation in minerals: the case of Cr3+ in spinel and pyrope garnet.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.166-167.TechnologyGarnet mineralogy
DS201412-0262
2013
Galoisy, L.Galoisy, L.Garnet: from stone to star.Elements, Vol. 9, 6, Dec. pp. 453-456.TechnologySpectroscopy
DS200712-0344
2006
Galopin de Carvallo, R.Galopin de Carvallo, R.The Braganca diamond discovered?Gems & Gemology, 4th International Symposium abstracts, Fall 2006, p.132-3. abstract onlyEurope, PortugalDiamonds notable
DS1984-0233
1984
Galperov, G.Diallo, D., Galperov, G.Tectonique de la Guinee OccidentalePangea., No. 2, JUNE, PP. 20-27.Guinea, West AfricaTectonics
DS1987-0536
1987
Galushkin, E.V.Novgorodova, M.I., Galushkin, E.V., Boyarskaya, R.V., Mokhov, A.V.Accessory minerals of lamproite like rocks of central Asia.(Russian)Izv. Akad. Nauk SSSR, Ser. Geol, No. 4, pp. 15-27RussiaBlank
DS1987-0537
1987
Galuskin, Ye.V.Novgorodova, M.I., Galuskin, Ye.V., Boyzarsdaya, R., Mokhov, A.V.Accessory minerals in lamprophyres of central Asia.(Russian)Izves.Akad. Nauk SSSR, Ser. Geol. (Russian), No. 4, pp. 15-27RussiaLamproite, Petrology
DS1995-0577
1995
Galvao, L.S.Galvao, L.S., Vitorello, F., Paradella, W.R.Spectroradiometric discrimination of laterites with principal components analysis and additive modelingRemote Sensing of Environment, Vol. 53, No. 2, Aug. pp. 70-75GlobalLaterites, Remote sensing
DS201312-0291
2012
Galvez, M.E.Galvez, M.E., Gaillardet, J.Historical constraints on the origins of the carbon cycle concept.Comptes Rendus Geoscience, Vol. 344, pp. 549-567.MantleCarbon cycle
DS201709-1957
2017
Galvez, M.E.Aulbach, S., Woodland, A.B., Vasileyev, P., Galvez, M.E., Viljoen, K.S.Effects of low pressure igneous processes and subduction on Fe3/Fe and redox state of mantle eclogites from Lace ( Kaapvaal craton).Earth and Planetary Science Letters, Vol. 474, pp. 283-295.Africa, South Africadeposit - Lace

Abstract: Reconstructing the redox state of the mantle is critical in discussing the evolution of atmospheric composition through time. Kimberlite-borne mantle eclogite xenoliths, commonly interpreted as representing former oceanic crust, may record the chemical and physical state of Archaean and Proterozoic convecting mantle sources that generated their magmatic protoliths. However, their message is generally obscured by a range of primary (igneous differentiation) and secondary processes (seawater alteration, metamorphism, metasomatism). Here, we report the Fe3+/SFe ratio and d18 O in garnet from in a suite of well-characterised mantle eclogite and pyroxenite xenoliths hosted in the Lace kimberlite (Kaapvaal craton), which originated as ca. 3 Ga-old ocean floor. Fe3+/SFe in garnet (0.01 to 0.063, median 0.02; n = 16) shows a negative correlation with jadeite content in clinopyroxene, suggesting increased partitioning of Fe3+ into clinopyroxene in the presence of monovalent cations with which it can form coupled substitutions. Jadeite-corrected Fe3+/SFe in garnet shows a broad negative trend with Eu*, consistent with incompatible behaviour of Fe3+ during olivine-plagioclase accumulation in the protoliths. This trend is partially obscured by increasing Fe3+ partitioning into garnet along a conductive cratonic geotherm. In contrast, NMORB-normalised Nd/Yb - a proxy of partial melt loss from subducting oceanic crust (<1) and metasomatism by LREE-enriched liquids (>1) - shows no obvious correlation with Fe3+/SFe, nor does garnet d18OVSMOW (5.14 to 6.21‰) point to significant seawater alteration. Median bulk-rock Fe3+/SFe is roughly estimated at 0.025. This observation agrees with V/Sc systematics, which collectively point to a reduced Archaean convecting mantle source to the igneous protoliths of these eclogites compared to the modern MORB source. Oxygen fugacites (fO2) relative to the fayalite-magnetite-quartz buffer (FMQ) range from ?log ? fO2 = FMQ-1.3 to FMQ-4.6. At those reducing conditions, the solubility of carbon in the fluids released by dehydration is higher than in fluids closer to FMQ. The implication is that Archean processes of C transport and deposition would have differed from those known in modern-style subduction zones, and diamond would have formed from methane-rich fluids. In addition, such reducing material could drive redox melting or freezing upon deep recycling and migration of CH4-bearing fluids into the ambient mantle.
DS201707-1339
2017
Galy, A.Kitayama, Y., Thomassot, E., Galy, A., Golovin, A., Korsakov, A., d'Eyrames, E., Assayag, N., Bouden, N., Ionov, D.Co-magmatic sulfides and sulfates in the Udachnaya-East pipe ( Siberia): a record of the redox state and isotopic composition of sulfur in kimberlites and their mantle sources.Chemical Geology, Vol. 455, pp. 315-330.Russiadeposit - Udachnaya East

Abstract: Kimberlites of the Udachnaya-East pipe (Siberia) include a uniquely dry and serpentine-free rock type with anomalously high contents of chlorine (Cl = 6.1 wt%), alkalies (Na2O + K2O = 10 wt%) and sulfur (S = 0.50 wt%), referred to as a “salty” kimberlite. The straightforward interpretation is that the Na-, K-, Cl- and S-rich components originate directly from a carbonate-chloride kimberlitic magma that is anhydrous and alkali-rich. However, because brines and evaporites are present on the Siberian craton, previous studies proposed that the kimberlitic magma was contaminated by the assimilation of salt-rich crustal rocks. To clarify the origin of high Cl, alkalies and S in this unusual kimberlite, here we determine its sulfur speciation and isotopic composition and compare it to that of non-salty kimberlites and kimberlitic breccia from the same pipe, as well as potential contamination sources (hydrothermal sulfides and sulfates, country-rock sediment and brine collected in the area). The average d34S of sulfides is - 1.4 ± 2.2‰ in the salty kimberlite, 2.1 ± 2.7‰ in the non-salty kimberlites and 14.2 ± 5.8‰ in the breccia. The average d34S of sulfates in the salty kimberlites is 11.1 ± 1.8‰ and 27.3 ± 1.6‰ in the breccia. In contrast, the d34S of potential contaminants range from 20 to 42‰ for hydrothermal sulfides, from 16 to 34‰ for hydrothermal sulfates, 34‰ for a country-rock sediment (Chukuck suite) and the regional brine aquifer. Our isotope analyses show that (1) in the salty kimberlites, neither sulfates nor sulfides can be simply explained by brine infiltration, hydrothermal alteration or the assimilation of known salt-rich country rocks and instead, we propose that they are late magmatic phases; (2) in the non-salty kimberlite and breccia, brine infiltration lead to sulfate reduction and the formation of secondary sulfides – this explains the removal of salts, alkali-carbonates and sulfates, as well as the minor olivine serpentinization; (3) hydrothermal sulfur was added to the kimberlitic breccia, but not to the massive kimberlites. In situ measurements of sulfides confirm this scenario, clearly showing the addition of two sulfide populations in the breccia (pyrite-pyrrhotites with average d34S of 7.9 ± 3.4‰ and chalcopyrites with average d34S of 38.0 ± 0.4‰) whereas the salty and non-salty kimberlites preserve a unique population of djerfisherites (Cl- and K-rich sulfides) with d34S values within the mantle range. This study provides the first direct evidence of alkaline igneous rocks in which magmatic sulfate is more abundant than sulfide. Although sulfates have been rarely reported in mantle materials, sulfate-rich melts may be more common in the mantle than previously thought and could balance the sulfur isotope budget of Earth's mantle.
DS202011-2033
2020
Galy, A.Casola, V., France, L., Galy, A., Bouden, N., Villeneuve, J.No evidence for carbon enrichment in the mantle source of carbonatites in eastern Africa.Geology, Vol. 48, 10, pp. 971976. pdfAfrica, Tanzaniadeposit - Oldoinyo Lengai

Abstract: Carbonatites are unusual, carbon-rich magmas thought to form either by the melting of a carbon-rich mantle source or by low-degree partial melting of a carbon-poor (<80 ppm C) mantle followed by protracted differentiation and/or immiscibility. Carbonate-bearing mantle xenoliths from Oldoinyo Lengai (East African Rift), the only active volcano erupting carbonatites, have provided key support for a C-rich mantle source. Here, we report unique microscale O and C isotopic analyses of those carbonates, which are present as interstitial grains in the silicate host lava, veins in the xenoliths, and pseudo-inclusions in olivine xenoliths. The d18O values vary little, from 19‰ to 29‰, whereas d13C values are more variable, ranging from -23‰ to +0.5‰. We show that such carbonate d18O values result from the low-temperature precipitation of carbonate in equilibrium with meteoric water, rather than under mantle conditions. In this framework, the observed d13C values can be reproduced by Rayleigh distillation driven by carbonate precipitation and associated degassing. Together with petrological evidence of a physical connection between the three types of carbonates, our isotopic data support the pedogenic formation of carbonates in the studied xenoliths by soil-water percolation and protracted crystallization along xenolith cracks. Our results refute a mechanism of C enrichment in the form of mantle carbonates in the mantle beneath the Natron Lake magmatic province and instead support carbonatite formation by low-degree partial melting of a C-poor mantle and subsequent protracted differentiation of alkaline magmas.
DS202012-2210
2020
Galy, A.Casola, V., France, L., Galy, A., Bouden, N., Villeneuve, J.No evidence for carbon enrichment in the mantle source of carbonatites in eastern Africa.Geology, Vol. 48, 10, 5p. PdfAfrica, Tanzaniacarbonatites

Abstract: Carbonatites are unusual, carbon-rich magmas thought to form either by the melting of a carbon-rich mantle source or by low-degree partial melting of a carbon-poor (<80 ppm C) mantle followed by protracted differentiation and/or immiscibility. Carbonate-bearing mantle xenoliths from Oldoinyo Lengai (East African Rift), the only active volcano erupting carbonatites, have provided key support for a C-rich mantle source. Here, we report unique microscale O and C isotopic analyses of those carbonates, which are present as interstitial grains in the silicate host lava, veins in the xenoliths, and pseudo-inclusions in olivine xenoliths. The d18O values vary little, from 19‰ to 29, whereas d13C values are more variable, ranging from -23‰ to +0.5‰. We show that such carbonate d18O values result from the low-temperature precipitation of carbonate in equilibrium with meteoric water, rather than under mantle conditions. In this framework, the observed d13C values can be reproduced by Rayleigh distillation driven by carbonate precipitation and associated degassing. Together with petrological evidence of a physical connection between the three types of carbonates, our isotopic data support the pedogenic formation of carbonates in the studied xenoliths by soil-water percolation and protracted crystallization along xenolith cracks. Our results refute a mechanism of C enrichment in the form of mantle carbonates in the mantle beneath the Natron Lake magmatic province and instead support carbonatite formation by low-degree partial melting of a C-poor mantle and subsequent protracted differentiation of alkaline magmas.
DS1988-0360
1988
Galymova, A.Klyuev, Yu.A., Galymova, A., Korneeva, I.I., Naletov, A.M., NepshaPhotoluminescence tomography as a method to image point defect distributions in crystals- nitrogen-vacancy pairs in syntheticdiamonds*technical noteNov. Obl. Primeniya Tekn.Almazov, (Russian), pp. 24-30RussiaLuminescence
DS1986-0693
1986
Gamarik, M.Y.Rybalko, S.I., Gamarik, M.Y., Rybalkova, E.A., Nagaleva, N.B.The finding of feldspar in diamond.(Russian)Mineral. Zhurnal, (Russian), Vol.8, No. 6, pp. 78-79RussiaBlank
DS1987-0610
1987
Gamarik, M.Ya.Ribalko, S.I., Metalidi, S.V., Gamarik, M.Ya., et al.Typomorphism of diamond crystals from ancient coarse grained rocks of the northwestern Ukrainian shield.(Russian)Akad. Nauk UKR.RSR Institute Geokhim. I Fiz. Mineral.(Russian), Vol. 1987, No. 6, pp. 27-29RussiaBlank
DS1987-0632
1987
Gamarnik, M. Ya.Rybalko, S.I., Metalidi, S.V., Gamarnik, M. Ya., et al.Typomorphism of diamond crystals from ancient coarse detritalrocks In the northwestern part of the Ukrainian shield.(Russian)Doklady Academy of Sciences Nauk. UKR. Miner., (Russian), No. 6, pp. 27-30RussiaBlank
DS1988-0588
1988
Gamarnik, M.Ya.Rybalko, S.I., Galii, G.A., Gamarnik, M.Ya., et al.Electron optical studies of zircon from kimberlites.(Russian)Ontogeniya Mineralov I Teknol Mineral Kiev.(Russian), pp. 160-165RussiaMircoprobe, Zircon
DS1985-0213
1985
Gamble, J.A.Gamble, J.A.The Mucurdo Volcanics of the Ross Dependency, East AntarcticConference Report of The Proceedings of The Meeting of The V, 1P. ABSTRACT.GlobalBasanite, Erebus
DS1988-0235
1988
Gamble, J.A.Gamble, J.A., McGibbon, F., Kyle, P.R., Menzies, M.A., Kirsch, I.Metasomatised xenoliths from Foster Crater Antarctica:implications for lithospheric structure and processes beneath the Transantarctic Mountain FrontJournal of Petrology, Special Volume 1988- Oceanic and Continental, pp. 109-138AntarcticaFoster Crater
DS1991-1100
1991
Gamble, J.A.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
DS1999-0235
1999
Gamble, J.A.Gamble, J.A., Wysoczanski, R.J., Meighan, I.G.Constraints on the age of the British Tertiary Volcanic Province from ion microprobe uranium-lead (U-Pb) SHRIMP ages...Journal of Geological Society of London, Vol. 156, No. 2, Mar. pp. 291-300.IrelandGeochronology - acid igneous rocks
DS2003-0546
2003
Gamble, J.A.Handler, M.R., Wysoczanski, R.J., Gamble, J.A.Proterozoic lithosphere in Marie Byrd Land, West Antarctica: Re Os systematics ofChemical Geology, Vol. 196, 1-4, pp. 131-45.AntarcticaGeochronology, Xenoliths
DS200412-0779
2003
Gamble, J.A.Handler, M.R., Wysoczanski, R.J., Gamble, J.A.Proterozoic lithosphere in Marie Byrd Land, West Antarctica: Re Os systematics of spinel peridotite xenoliths.Chemical Geology, Vol. 196, 1-4, pp. 131-45.AntarcticaGeochronology Xenoliths
DS202003-0335
2020
Gamel El Dien, H.Doucet, L.S., Li, Z-X., Ernst, R.E., Kirscher, U., Gamel El Dien, H., Mitchell, R.N.Coupled supercontinent-mantle plume events evidence by oceanic plume record.Geology, Vol. 48, pp. 159-163.Mantle, Africageodynamics

Abstract: The most dominant features in the present-day lower mantle are the two antipodal African and Pacific large low-shear-velocity provinces (LLSVPs). How and when these two structures formed, and whether they are fixed and long lived through Earth history or dynamic and linked to the supercontinent cycles, remain first-order geodynamic questions. Hotspots and large igneous provinces (LIPs) are mostly generated above LLSVPs, and it is widely accepted that the African LLSVP existed by at least ca. 200 Ma beneath the supercontinent Pangea. Whereas the continental LIP record has been used to decipher the spatial and temporal variations of plume activity under the continents, plume records of the oceanic realm before ca. 170 Ma are mostly missing due to oceanic subduction. Here, we present the first compilation of an Oceanic Large Igneous Provinces database (O-LIPdb), which represents the preserved oceanic LIP and oceanic island basalt occurrences preserved in ophiolites. Using this database, we are able to reconstruct and compare the record of mantle plume activity in both the continental and oceanic realms for the past 2 b.y., spanning three supercontinent cycles. Time-series analysis reveals hints of similar cyclicity of the plume activity in the continent and oceanic realms, both exhibiting a periodicity of ~500 m.y. that is comparable to the supercontinent cycle, albeit with a slight phase delay. Our results argue for dynamic LLSVPs where the supercontinent cycle and global subduction geometry control the formation and locations of the plumes.
DS202008-1384
2020
Gamel El Dien, H.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
GamelEl Dien, H.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.
DS201012-0128
2010
Gamero, E.J.Courtier, A.M., Gaherty, J.B., Revenaugh, J., Bostock, M.G., Gamero, E.J.Seismic anisotropy associated with continental lithosphere accretion beneath the CANOE array, northwestern Canada.Geology, Vol. 38, 10, pp. 887-890.Canada, Alberta, Northwest TerritoriesGeophysics - seismics
DS201112-0571
2011
Gamero, E.J.Lay, T., Gamero, E.J.Deep mantle seismic modeling and imaging.Annual Review of Earth and Planetary Sciences, Vol. 39, pp. 91-123.MantleGeophysics - seismics
DS1993-0479
1993
Gamey, J.Gamey, J.A statistical analysis of airborne geophysical targets in the search fordiamonds. #1Northwest Territories Exploration Overview for 1993, November pp. 30-31.Northwest TerritoriesGeophysics, Magnetics
DS1994-0567
1994
Gamey, T.J.Gamey, T.J.A statistical analysis of airborne geophysical targets in the search fordiamonds. #2The Professional Association of Geologists and Geophysicists of QuTbec (APGGQ) 1994, held Val'D'Or Aprl 13-15., 1p. abstractNorthwest Territories, QuebecGeophysics
DS2003-1039
2003
Gammon, J.B.Owsiacki, I., Gammon, J.B.Reaching out - MDMN's "3 Offers" to Ontario's Far North First NationsOntario Geological Survey Open File, No. 6120, pp. I 1-4.OntarioLegal - First Nations
DS200412-1487
2003
Gammon, J.B.Owsiacki, I., Gammon, J.B.Reaching out - MDMN's '3 Offers' to Ontario's Far North First Nations.Ontario Geological Survey Open File, No. 6120, pp. I 1-4.Canada, OntarioLegal - First Nations
DS1991-0601
1991
Gamond, J.F.Gratier, J.P., Gamond, J.F.Transition between seismic and aseismic deformation in the upper crustDeformation Mechanisms, Rheology and Tectonics, editors Knipe, R.J., No. 54, pp. 461-473GlobalTectonics, Geophysics -seismics
DS1960-1001
1968
Gamyanina, V.V.Nekrasova, R.A., Gamyanina, V.V.The Composition of Rare Earth Elements in Kimberlite MineralDoklady Academy of Science USSR, Earth Science Section., Vol. 182, PP. 195-198.RussiaBlank
DS1970-0156
1970
Gamyanina, V.V.Nekrasova, R.A., Gamyanina, V.V., Rozhdestvenskaya, I.V.The Zro2lhfo2 Ratio in Zircons from Kimberlites and \ Alluvial Sediments.Geochemistry International, Vol. 7, No. 3, PP. 536-542.RussiaBlank
DS1970-0157
1970
Gamyanina, V.V.Nikisov, K.N., Gamyanina, V.V.Trace Elements in Perovskite from Intrusive KimberlitesIn: Geology, Petrography And Mineralogy of The Northeast Par, AKAD. NAUK SSSR, PP. 281-287.RussiaBlank
DS202004-0502
2020
Gan, C.Cawood, P.A., Wang, W., Zhao, T., Xu, Y., Mulder, J.A., Pisarevsky, S.A., Zhang, L., Gan, C., He, H., Liu, H., Qi, L., Wang, Y., Yao, J., Zhao, G., Zhou, M-F., Zi, J-W.Deconstructing south China and consequences for reconstructing Nuna and Rodinia.Earth-Science Reviews, in press available, 70p. PdfChinatectonics

Abstract: Contrasting models for internal and external locations of South China within the Nuna and Rodinia supercontinents can be resolved when the current lithotectonic associations of Mesoproterozoic and older rocks units that constitute the craton are redefined into four lithotectonic domains: Kongling, Kunming-Hainan, Wuyi, and Coastal. The Kongling and Kunming-Hainan domains are characterized by isolated Archean to early Paleoproterozoic rock units and events and crop out in northern and southern South China, respectively. The Kunming-Hainan Domain is preserved in three spatially separated regions at Kunming (southwestern South China), along the Ailaoshan shear zone, and within Hainan Island. Both domains were affected by late Paleoproterozoic tectonothermal events, indicating their likely juxtaposition by this time to form the proto-Yangtze Block. Late Paleoproterozoic and Mesoproterozoic sedimentary and igneous rock units developed on the proto-Yangtze Block, especially in its southern portions, and help link the rock units that formed along the shear zone at Ailaoshan and on Hainan Island into a single, spatially unified unit prior to Paleozoic to Cenozoic structural disaggregation and translation. The Wuyi Domain consists of late Paleoproterozoic rock units within a NE-SW trending, fault-bounded block in eastern South China. The Coastal Domain lies east of the Wuyi domain and is inferred to constitute a structurally separate block. Basement to the domain is not exposed, but zircon Hf model ages from Mesozoic granites suggest Mesoproterozoic basement at depth. The Archean to Paleoproterozoic tectonothermal record of the Kongling and Kunming-Hainan domains corresponds closely with that of NW Laurentia, suggesting all were linked, probably in association with assembly and subsequent partial fragmentation of the Nuna supercontinent. Furthermore, the age and character of Mesoproterozoic magmatism and detrital zircon signature of sedimentary rocks in the proto-Yangtze Block matches well with western Laurentia and eastern Australia-Antarctica. In particular, the detrital zircon signature of late Paleoproterozoic to early Mesoproterozoic sedimentary units in the block (e.g. Dongchuan Group) share a similar age spectrum with the Wernecke Supergroup of northwest Laurentia. This, together with similarities in the type and age of Fe-Cu mineralization in the domain with that in eastern Australia-Antarctica, especially northeast Australia, suggests a location adjacent to northwest Laurentia, southern Siberia, and northeast Australia within the Nuna supercontinent. The timing and character of late Paleoproterozoic magmatic activity in the Wuyi domain along with age of detrital zircons in associated sedimentary rocks matches the record of northern India. During rifting between Australia-Antarctica and Laurentia in the late Mesoproterozoic, the proto-Yangtze Block remained linked to northeast Australia. During accretionary orogenesis in the early Neoproterozoic, the proto-Yangtze Block assembled with the Wuyi Domain along the northern margin of India. The Coastal domain likely accreted at this time forming the South China Craton. Displacement of the Hainan and Ailaoshan assemblages from southwest of the Kunming assemblage likely occurred in the Cenozoic with the activation of the Ailaoshan-Red River fault system but could have begun in the early to mid-Paleozoic based on evidence for tectonothermal events in the Hainan assemblage.
DS2001-0442
2001
Gan, J.Han, B-F., Zheng, Y., Gan, J., Chang, Z.The Louzidian normal fault near Chifeng: master fault of a quasi metamorphic core complex.International Geology Review, Vol. 43, pp. 254-64.GlobalTectonics, Qinling Dabie Orogenic belt, ultra high pressure (UHP)
DS202101-0027
2020
Ganade, C.E.Pessano, P.C., Ganade, C.E., Tupinamba, M., Teixeira, W.Updated map of the mafic dike swarms of Brazil based on airborne geophysical data.Journal of South American Earth Sciences, in press available, 16p. PdfSouth America, Brazilgeophysics

Abstract: Identification of mafic dike swarms and LIPs (Large Igneous Provinces) are of vital importance in geologic history because they provide information on geodynamics, mantle geochemistry, and paleomagnetism. These data provide key information for paleogeographic reconstructions with the aid of barcode matches and precise radiometric ages. Considering such issues, the Brazilian Precambrian shield can be used as a case for refining the cartography of the relevant intraplate activity (e.g., dikes, sills, flood basalts) in space and time. This work presents an updated map of Brazilian mafic dike swarms produced from airborne geophysical maps (Series 1000 - Geological Survey of Brazil). Linear and strong anomalies found on aeromagnetic maps using First Vertical Derivative of the Magnetic Field and Amplitude of the Analytic Signal were mapped on a GIS platform. The obtained data were compared to ternary radiometric maps and geological maps in order to exclude those that do not correspond to mafic dikes. The remaining structures - those believed to represent mafic dikes - were classified based on data compiled from the literature. The updated map exhibits more than 5000 elements, including dikes and magmatic suites, in which about 75% were geologically identified and divided into 60 dike swarms and 10 igneous suites and/or units. The dikes were grouped into sixteen extensional episodes from the Archean to the Cenozoic, although some are related to extension/transtension domains within regional compressive zones akin to orogenic settings. The most frequent records refer to the Proterozoic, representing intraplate episodes, some of them consistent with LIPs. The dataset also includes a large record of the Mesozoic age, which corresponds to major LIP events related to the opening of the Atlantic Ocean and the fragmentation of Gondwana.
DS1988-0613
1988
GandhiScharer, U., Krogh, T.E., Wardle, Ryan, Gandhiuranium-lead (U-Pb) ages of early to middle Proterozoic volcanism and metamorphism in the Makkovik Orogen, Labrador.Canadian Journal of Earth Sciences, Vol. 25, pp. 1098-1107.LabradorGeochronology
DS2001-0352
2001
Gandhi, S.S.Gandhi, S.S., Mortensen, J.K., Prasad, N., Van BreemenMagmatic evolution of the southern Great Bear continental arc, northwestern Canadian shield....Canadian Journal of Earth Sciences, Vol. 38, No. 5, May, pp. 767-85.Northwest TerritoriesGeochronology - Slave Craton
DS200612-0422
2005
Gandhi, S.S.Gandhi, S.S., Van Breemen, O.SHRIMP U Pb geochronology of detrital zircons from the Treasure Lake Group - new evidence for Paleoproterozoic collisional tectonics in the southern Hottah terrane.Canadian Journal of Earth Sciences, Vol. 42, 5, pp. 833-845.Canada, Northwest TerritoriesGeochronology - not specific to diamonds
DS2002-0466
2002
Gandhok, G.Fodor, R.V., Sial, A.N., Gandhok, G.Petrology of spinel peridotite xenoliths from northeastern Brasil: lithosphere with a high geothermal gradient imparted by Fernando de Nornha plume.Journal of South American Earth Sciences, Vol.15,2,June pp. 183-98.BrazilGeothermometry, Hot spots
DS2002-0467
2002
Gandhok, G.Fodor, R.V., Sial, A.N., Gandhok, G.Petrology of spinel peridotite xenoliths from northeastern Brasil: lithosphere with a high geothermal gradient imparted by Fernando de Noronha plume.Journal of South American Earth Sciences, Vol. 15, No. 2, pp. 199-214.BrazilTectonics, Xenoliths
DS2002-0468
2002
Gandhok, G.Fodor, R.V., Sial, A.N., Gandhok, G.Petrology of spinel peridotite xenoliths from northeastern Brasil: lithosphere with a high geothermal gradient imparted by Fernando de Noronha plume.Journal of South American Earth Sciences, Vol.15,2,June pp. 199-214.Brazil, northeastMagmatism, hot spots, Geothermometry
DS1991-0494
1991
Gandhok, G.R.Fodor, R.V., Gandhok, G.R., Sial, A.N.Vertical sampling of mantle beneath northeastern Brasil as represented by ultramafic xenoliths and megacrysis in Tertiary basaltsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 101-102BrazilXenoliths, Mantle peridotite
DS201112-0734
2010
Gandini, A.L.Newman, J.A., Teixeira Carvalho de Newman, D., Gandini, A.L., Souza Gomes, N., Krambrock, K.W.H., Pimenta, M.A.Caracterizacao mineralogica dos diamantes policristalinos (carbonados) da regiao de Santa Elena de Uairen, estado Bolivar, Venezuela.5th Brasilian Symposium on Diamond Geology, Nov. 6-12, abstract p. 46-47.South America, VenezuelaCarbonado
DS201112-0735
2010
Gandini, A.L.Newman, J.A., Teixeira Carvallo de Newman, D.,Gandini, A.L.Classificacao tipologica do diamante da regiao de Santa Elena de Uairen, estado Bolivar, Venezuela, baseada na espectroscopia de absorcao no infravermelho.5th Brasilian Symposium on Diamond Geology, Nov. 6-12, abstract p. 41-42.South America, VenezuelaDiamond morphology
DS200512-0310
2004
Ganero, E.J.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
DS202010-1844
2020
Ganesan, K.Genish, H., Ganesan, K., Stacey, A., Prawer, S., Rosenbluh, M.Effect of radiation damage on the quantum optical properties of nitrogen vacancies in diamond.Diamond & Related Materials, Vol. 109, 108049, 6p. PdfMantlenitrogen

Abstract: Single crystal diamond (<5?ppm nitrogen) containing native NV centers with coherence time of 150?µs was irradiated with 2?MeV alpha particles, with doses ranging from 1012 ion/cm2 to 1015 ion/cm2. The effect of ion damage on the coherence time of NV centers was studied using optically detected magnetic resonance and supplemented by fluorescence and Raman microscopy. A cross-sectional geometry was employed so that the NV coherence time could be measured as a function of increasing defect concentration along the ion track. Surprisingly, although the ODMR contrast was found to decrease with increasing ion induced vacancy concentration, the measured decoherence time remained undiminished at 150us despite the estimated vacancy concentration reaching a value of 40?ppm at the end of range. These results suggest that ion induced damage in the form of an increase in vacancy concentration does not necessarily result in a significant increase in the density of the background spin bath.
DS200412-0603
2004
Ganesha Raj, K.Ganesha Raj, K.Major lineaments of Karnataka State and their relation to seismicity: a remote sensing based analysis.Journal Geological Society of India, Vol. 63, 4, pp. 430-439.India, KarnatakaStructure, 43 major lineaments
DS201710-2227
2017
Ganey, G.Q.Ganey, G.Q., Loso, M.G., Burgess, A.B., Dial, R.J.The role of microbes in snowmelt and radiative forcing on an an Alaskan icefield. Red algaeNature Geoscience, Sept. 18, onlineUnited States, Alaskageomorphology

Abstract: A lack of liquid water limits life on glaciers worldwide but specialized microbes still colonize these environments. These microbes reduce surface albedo, which, in turn, could lead to warming and enhanced glacier melt. Here we present results from a replicated, controlled field experiment to quantify the impact of microbes on snowmelt in red-snow communities. Addition of nitrogen-phosphorous-potassium fertilizer increased alga cell counts nearly fourfold, to levels similar to nitrogen-phosphorus-enriched lakes; water alone increased counts by half. The manipulated alga abundance explained a third of the observed variability in snowmelt. Using a normalized-difference spectral index we estimated alga abundance from satellite imagery and calculated microbial contribution to snowmelt on an icefield of 1,900?km2. The red-snow area extended over about 700?km2, and in this area we determined that microbial communities were responsible for 17% of the total snowmelt there. Our results support hypotheses that snow-dwelling microbes increase glacier melt directly in a bio-geophysical feedback by lowering albedo and indirectly by exposing low-albedo glacier ice. Radiative forcing due to perennial populations of microbes may match that of non-living particulates at high latitudes. Their contribution to climate warming is likely to grow with increased melt and nutrient input.
DS200412-1320
2004
Gang, L.Mingjie, Z., Zianbin, W., Gang, L., Tongwei, Z., Wenrui, B.Compositions of upper mantle fluids beneath eastern China: implications for mantle evolution.Acta Geologica Sinica, Vol. 78, 1, pp. 125-130.ChinaGeochemistry
DS1994-0568
1994
Gang ChaiGang ChaiChina's mineral endowmentAsian Mining Opportunities Symposium Aug. 3, 4th, 23pChinaEconomics
DS1994-0569
1994
Gang ChaiGang ChaiChina's mineral endowmentAsian Mining Opportunities Symposium Aug. 3, 4., 23p.ChinaMining, Economics -mentions diamonds
DS1990-0511
1990
Gang LuGang 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
DS2003-1189
2003
Ganga, J.Rotman, A., Ganga, J., Nosiko, S.Pipe Catoca, an example of the weakly eroded kimberlites from north east Angola8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractAngolaKimberlite geology and economics, Deposit - Catoca
DS200512-0914
2004
Ganga, J.Rotman, A.Y., Ganga, J., Nosyko, S.F., Shimupi, J., Zintchouk, N.N., Somov, S.V.Kimberlites of Angola: structural tectonic position and geology.Deep seated magmatism, its sources and their relation to plume processes., pp. 178-193.Africa, AngolaTectonics
DS1960-1106
1969
Gangadharam, E.V.Gangadharam, E.V., Aswathanarayana, V.Trace Element Content of Kimberlites of South IndiaEos, Vol. 50, P. 341. (abstract.).IndiaMineralogy
DS1970-0293
1971
Gangadharam, E.V.Gangadharam, E.V., Aswathanarayana, V.Th/u Ratio As an Aid in Prospecting for Diamonds in the Kimberlitic Rocks of India.Current Science., Vol. 24, DECEMBER, PP. 663-664.IndiaProspecting
DS1991-0531
1991
Gangi, A.F.Gangi, A.F.World rift systems. Special issueTectonophysics, Vol. 197, No. 2-4, pp. 99-390GlobalTectonics, World rift systems
DS1980-0135
1980
Gangopadhyay, S.Gangopadhyay, S.Bibliography on Dyke and Pipe Rocks of IndiaIndian Minerals, Vol. 34, No. 3, , PP. 43-52.IndiaBibliography
DS1996-0759
1996
Gangui, A.H.Kley, J., Gangui, A.H., Kruger, D.Basement involved blind thrusting in the eastern Cordillera Oriental:evidence from cross sect. balanceTectonophysics, Vol. 259, No. 1-3, June 30, pp. 171-184BoliviaGeophysics -magnetotellurics, gravity, Tectonics
DS2001-1057
2001
Ganguly, A.Shanker, R., Nag, S., Ganguly, A., Absar, Rawat, SinghAre Majhgawan Hinota pipe rocks truly group I kimberlite?Indian Acad. Sciences Earth and Plan., Vol. 110, No. 1, pp. 63-76.IndiaKimberlite - classification, Deposit - Majhgawan
DS200412-1793
2003
Ganguly, A.Shanker, R., Nag, S., Ganguly, A., Rawat, B.P.Chemistry of common and minor minerals in orangeite ( group II kimberlite) of Majhgawan, Panna District, Madhya Pradesh, India.Indian Journal of Geology, Vol. 73, pp. 207-220.India, Madhya PradeshGeochemistry - orangeite
DS1987-0234
1987
Ganguly, J.Ganguly, J., Bhattacharya, P.K.Xenoliths in Proterozoic kimberlites from southern India:petrology and geophysical implicationsin: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 249-266IndiaGeophysics, Analyses p. 251-2 ultrab
DS1992-0511
1992
Ganguly, J.Ganguly, J.Comments on evaluation of thermobarometers for garnet peridotites. Response to comments by Finnerty and BoydGeochimica et Cosmochimica Acta, Vol. 56, No. 2, February pp. 841-860GlobalGeothermometry, Garnet peridotites
DS200512-0311
2005
Ganguly, J.Ganguly, J.Adiabatic decompression and melting of mantle rocks: an irreversible thermodynamic analysis.Geophysical Research Letters, Vol. 32, 6, March 28, L06312MantleMelting
DS200612-0423
2006
Ganguly, J.Ganguly, J., Sacena, S.K., Freed, A.M.Density variation in subducting slabs and surrounding upper mantle: understanding stagnation vs penetration of the slabs at 670 km discontinuity.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p.102.MantleSubduction
DS200912-0241
2009
Ganguly, J.Ganguly, J., Freed, A.M., Saxena, S.K.Density profiles of oceanic slabs and surrounding mantle: integrated thermodynamic and thermal modeling, and implications for the fate of slabs at the 660 kmPhysics of the Earth and Planetary Interiors, Vol. 172, 3-4, pp. 257-267.MantleGeothermometry
DS200912-0764
2009
Ganguly, J.Tirose, M., Ganguly, J., Morgan, J.P.Modeled petrological geodynamics in the Earth's mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 10, Q04012.MantleThermometry
DS1994-0570
1994
Ganguly, P.Ganguly, P., et al.Evidence for superconductivity onset at 40 K in a carbon based systemCurrent Science, Vol. 67, No. 3, August 10, pp. 202-204.MantleCarbon
DS201511-1874
2015
Ganguly, S.Saha, A., Manikyamba, C., Santosh, M., Ganguly, S., Khelen, A.C.Platinum Group Elements ( PGE) geochemistry of komatiites and boninites from Dharwar Craton, India: implications for mantle melting processes.Journal of Asian Earth Sciences, Vol. 105, pp. 300-319.IndiaBoninites

Abstract: High MgO volcanic rocks having elevated concentrations of Ni and Cr are potential hosts for platinum group elements (PGE) owing to their primitive mantle origin and eruption at high temperatures. Though their higher PGE abundance is economically significant in mineral exploration studies, their lower concentrations are also valuable geochemical tools to evaluate petrogenetic processes. In this paper an attempt has been made to evaluate the PGE geochemistry of high MgO volcanic rocks from two greenstone belts of western and eastern Dharwar Craton and to discuss different mantle processes operative at diverse geodynamic settings during the Neoarchean time. The Bababudan greenstone belt of western and Gadwal greenstone belt of eastern Dharwar Cratons are dominantly composed of high MgO volcanic rocks which, based on distinct geochemical characteristics, have been identified as komatiites and boninites respectively. The Bababudan komatiites are essentially composed of olivine and clinopyroxene with rare plagioclase tending towards komatiitic basalts. The Gadwal boninites contain clinopyroxene, recrystallized hornblende with minor orthopyroxene, plagioclase and sulphide minerals. The Bababudan komatiites are Al-undepleted type (Al2O3/TiO2 = 23-59) with distinctly high MgO (27.4-35.8 wt.%), Ni (509-1066 ppm) and Cr (136-3036 ppm) contents. These rocks have low SPGE (9-42 ppb) contents with 0.2-2.4 ppb Iridium (Ir), 0.2-1.4 ppb Osmium (Os) and 0.4-4.4 ppb Ruthenium (Ru) among Iridium group PGE (IPGE); and 1.4-16.2 ppb Platinum (Pt), 2.8-19 ppb Palladium (Pd) and 0.2-9.8 ppb Rhodium (Rh) among Platinum group PGE (PPGE). The Gadwal boninites are high-Ca boninites with CaO/Al2O3 ratios varying between 0.8 and 1.0, with 12-24 wt.% MgO, 821-1168 ppm Ni and 2307-2765 ppm Cr. They show higher concentration of total PGE (82-207 ppb) with Pt concentration ranging from 13 to 19 ppb, Pd between 65 and 180 ppb and Rh in the range of 1.4-3 ppb compared to the Bababudan komatiites. Ir, Os and Ru concentrations range from 0.6 to 2.2 ppb, 0.2 to 0.6 ppb and 1.4 to 2.6 ppb respectively in IPGE. The PGE abundances in Bababudan komatiites were controlled by olivine fractionation whereas that in Gadwal boninites were influenced by fractionation of chromite and sulphides. The Al-undepleted Bababudan komatiites are characterized by low CaO/Al2O3, (Gd/Yb)N, (La/Yb)N, with positive Zr, Hf, Ti anomalies and high Cu/Pd, Pd/Ir ratios at low Pd concentrations suggesting the derivation of parent magma by high degrees (>30%) partial melting of mantle under anhydrous conditions at shallow depth with garnet as a residual phase in the mantle restite. The komatiites are geochemically analogous to Al-undepleted Munro type komatiites and their PGE compositions are consistent with Alexo and Gorgona komatiites. The S-undersaturated character of Bababudan komatiites is attributed to decompression and assimilation of lower crustal materials during magma ascent and emplacement. In contrast, the higher Al2O3/TiO2, lower (Gd/Yb)N, for Gadwal boninites in combination with negative Nb, Zr, Hf, Ti anomalies and lower Cu/Pd at relatively higher Pd/Ir and Pd concentrations reflect high degree melting of refractory mantle wedge under hydrous conditions in an intraoceanic subduction zone setting. Higher Pd/Ir ratios and S-undersaturation of these boninites conform to influx of fluids derived by dehydration of subducted slab resulting into high fluid pressure and metasomatism of mantle wedge.
DS201707-1361
2017
Ganguly, S.Saha, A., Ganguly, S., Ray, J., Koeberl, C., Thoni, M., Sarbajna, C., Sawant, S.S.Petrogenetic evolution of Cretaceous Samchampi Samteran alkaline complex, Mikir Hills, northeast India: implications on multiple melting events of heterogeneous plume and metasomatized sub continental lithospheric mantle.Gondwana Research, Vol. 48, pp. 237-256.Indiacarbonatite

Abstract: The Samchampi (26° 13'N: 93° 18'E)-Samteran (26° 11'N: 93° 25'E) alkaline complex (SSAC) occurs as an intrusion within Precambrian basement gneisses in the Karbi-Anglong district of Assam, Northeastern India. This intrusive complex comprises a wide spectrum of lithologies including syenite, ijolite-melteigite, alkali pyroxenite, alkali gabbro, nepheline syenite and carbonatite (nepheline syenites and carbonatites are later intrusives). In this paper, we present new major, trace, REE and Sr-Nd isotope data for different lithologies of SSAC and discuss integrated petrological and whole rock geochemical observations with Sr-Nd isotope systematics to understand the petrogenetic evolution of the complex. Pronounced LILE and LREE enrichment of the alkaline-carbonatite rocks together with steep LREE/HREE profile and flat HREE-chondrite normalized patterns provide evidence for parent magma generation from low degree partial melting of a metasomatized garnet peridotite mantle source. LILE, HFSE and LREE enrichments of the alkaline-silicate rocks and carbonatites are in agreement with the involvement of a mantle plume in their genesis. Nb-Th-La systematics with incompatible trace element abundance patterns marked by positive Nb-Ta anomalies and negative K, Th and Sr anomalies suggest contribution from plume-derived OIB-type mantle with recycled subduction component and a rift-controlled, intraplate tectonic setting for alkaline-carbonatite magmatism giving rise to the SSAC. This observation is corroborated by enriched 87Sr/86Srinitial (0.705562 to 0.709416) and 143Nd/144Ndinitial (0.512187 to 0.512449) ratios for the alkaline-carbonatite rocks that attest to a plume-related enriched mantle (~ EM II) source in relation to the origin of Samchampi-Samteran alkaline complex. Trace element chemistry and variations in isotopic data invoke periodic melting of an isotopically heterogeneous, metasomatized mantle and generation of isotopically distinct melt batches that were parental to the different rocks of SSAC. Various extents of plume-lithosphere interaction also accounts for the trace element and isotopic variations of SSAC. The Srinitial and Ndinitial (105 Ma) isotopic compositions (corresponding to eNd values of - 6.37 to - 1.27) of SSAC are consistent with those of Sung Valley, Jasra, Rajmahal tholeiites (Group II), Sylhet Traps and Kerguelen plateau basalts.
DS201903-0515
2019
Ganguly, S.Han, Y-S., Santosh, M., Ganguly, S., Li, S-S.Evolution of a Mesoarchean suprasubduction zone mantle wedge in the Dharwar Craton, southern India: evidence from petrology, geochemistry, zircon U-Pb geochronology, and Lu-Hf isotopes.Geological Journal, doi:10.1002/gj.3440Indiacraton

Abstract: Petrological, geochemical, and zircon U-Pb geochronological features of Archean ultramafic-mafic complexes formed in subduction-related settings provide significant insights into mantle source and geodynamic processes associated with subduction-accretion-collision events in the early Earth. Here, we investigate a suite of serpentinized dunite, dunite, pyroxenite, and clinopyroxenite from an ultramafic complex along the collisional suture between the Western Dharwar Craton (WDC) and the Central Dharwar Craton (CDC) in southern India. We present petrology, mineral chemistry, zircon U-Pb geochronology, rare earth element (REE), Lu-Hf isotopes, and whole-rock geochemistry including major, trace element, and platinum-group element (PGE) data with a view to investigate the magmatic and metasomatic processes in the subduction zone. Mineral chemistry data from chromite associated with the serpentinised ultramafic rocks show distinct characteristics of arc-related melt. Zircon U-Pb data from the ultramafic suite define different age populations, with the oldest ages at 2.9 Ga, and the dominant age population showing a range of 2.8-2.6 Ga. The early Paleoproterozoic (ca. 2.4 Ga) metamorphic age is considered to mark the timing of collision of the two WDC and CDC. Zircon REE patterns suggest the involvement continental crust components in the magma source. Zircon Lu-Hf analysis yields both positive and negative eHf(t) values from -3.9 to 1.5 with Hf-depleted model ages (TDM) of 3,041-3,366 Ma for serpentinised dunite and -0.2-2.0 and 2,833-2,995 Ma for pyroxenite, suggesting that the magma was sourced from depleted mantle and was contaminated with the ancient continental crust. Geochemical data show low MgO/SiO2 values and elevated Al2O3/TiO2 ratios, implying subduction-related setting. The serpentinized dunites and dunites show mild LREE enrichment over HREE, with relatively higher abundance of LILE (Ba, Sr) and depletion in HFSE (Nb, Zr), suggesting fluid-rock interaction, melt impregnation, and refertilization processes. The PGE data suggest olivine, chromite, and sulphide fractionations associated with subduction processes. Our study on the Mesoarchean to Neoarchean ultramafic complex provides important insights to reconstruct the history of the crust-mantle interaction in an Archean suprasubduction zone mantle wedge.
DS202005-0761
2019
Ganguly, S.Singh, T.D., Manikyamba, C., Subramanyam, K.S.V., Ganguly, S., Khelen, A., Ramakrsihna Reddy, N.Mantle heterogeneity, plume-lithosphere interaction at rift controlled ocean-continent transition zone: evidence from trace PGE geochemistry of Vempalle flows, Cuddapah basin India.Geoscience Frontiers, in press, 20p. PdfIndiaREE

Abstract: This study reports major, trace, rare earth and platinum group element compositions of lava flows from the Vempalle Formation of Cuddapah Basin through an integrated petrological and geochemical approach to address mantle conditions, magma generation processes and tectonic regimes involved in their formation. Six flows have been identified on the basis of morphological features and systematic three-tier arrangement of vesicular-entablature-colonnade zones. Petrographically, the studied flows are porphyritic basalts with plagioclase and clinopyroxene representing dominant phenocrystal phases. Major and trace element characteristics reflect moderate magmatic differentiation and fractional crystallization of tholeiitic magmas. Chondrite-normalized REE patterns corroborate pronounced LREE/HREE fractionation with LREE enrichment over MREE and HREE. Primitive mantle normalized trace element abundances are marked by LILE-LREE enrichment with relative HFSE depletion collectively conforming to intraplate magmatism with contributions from sub-continental lithospheric mantle (SCLM) and extensive melt-crust interaction. PGE compositions of Vempalle lavas attest to early sulphur-saturated nature of magmas with pronounced sulphide fractionation, while PPGE enrichment over IPGE and higher Pd/Ir ratios accord to the role of a metasomatized lithospheric mantle in the genesis of the lava flows. HFSE-REE-PGE systematics invoke heterogeneous mantle sources comprising depleted asthenospheric MORB type components combined with plume type melts. HFSE-REE variations account for polybaric melting at variable depths ranging from garnet to spinel lherzolite compositional domains of mantle. Intraplate tectonic setting for the Vempalle flows with P-MORB affinity is further substantiated by (i) their origin from a rising mantle plume trapping depleted asthenospheric MORB mantle during ascent, (ii) interaction between plume-derived melts and SCLM, (iii) their rift-controlled intrabasinal emplacement through Archean-Proterozoic cratonic blocks in a subduction-unrelated ocean-continent transition zone (OCTZ). The present study is significant in light of the evolution of Cuddapah basin in the global tectonic framework in terms of its association with Antarctica, plume incubation, lithospheric melting and thinning, asthenospheric infiltration collectively affecting the rifted margin of eastern Dharwar Craton and serving as precursors to supercontinent disintegration.
DS201212-0026
2012
Ganino, C.Arndt, N., Ganino, C.Deposits formed by sedimentary and surface processes.Metals and Society, and introduction to Economic Geology, Springer Publ., Chapter 5 pp. 113-140.GlobalAlluvials
DS200612-0424
2006
Ganley, M.Ganley, M.Conflict: the sixth C.Canadian Diamonds, Summer, pp. 26-32, 48.AfricaHistory - Kimberley Process
DS200612-0425
2005
Ganley, M.Ganley, M.Frozen in time... the North's regulatory process is too slow. Can anything be done to pull the process forward.Mining North, pp. 28,30,31.Canada, Northwest TerritoriesNews item - legal not specific to diamonds
DS200712-0345
2006
Ganley, M.Ganley, M.Artist of the DEAL. Profile of Eira Thomas and chosen Canadian Diamonds 2006 Person of the Year.Canadian Diamonds, pp. 27-32.CanadaNews item - profile Eira Thomas
DS200712-0346
2007
Ganley, M.Ganley, M.Mind the gap.... Diavik mine set a record for diamond production in 2006.. 9.8 million carats.Canadian Diamonds, Spring, pp. 26-30.Canada, Northwest TerritoriesDeposit - Diavik - production
DS200812-0381
2007
Ganley, M.Ganley, M.Target practice .. Government of NWT has suffered share of setbacks and blunders .. with new legislative assembly in place, might it improve its aim?Canadian Diamonds, Fall, pp.20-24.Canada, Northwest TerritoriesOverview - legal
DS200812-0382
2008
Ganley, M.Ganley, M.Will Tahera make it?UpHere Business, Vol. 1, 1, pp. 32-33,34, 36,38.Canada, NunavutJericho mine
DS1993-0480
1993
Gann, J.T.Gann, J.T.MudScan; PC based sidescan sonar real-time dat a acquisition, logging and display systemUnited States Geological Survey (USGS) Open File, No. 93-0242, 23p. $ 3.50GlobalComputer, Program - MudScan
DS201504-0185
2015
Ganne, J.Block, S., Ganne, J., Baratoux, A.Z., Parra-Avila, L.A., Jessell, M., Ailleres, L., Siebenaller, L.Petrological and geochronological constraints on lower crust exhumation during Paleoproterozoic (Eburnean) Orogeny, NW Ghana, West African craton.Journal of Metamorphic Geology, Vol. 33, 5, pp. 463-494.Africa, GhanaGeochronology

Abstract: New petrological and geochronological data are presented on high-grade ortho- and paragneisses from northwestern Ghana, forming part of the Paleoproterozoic (2.25-2.00 Ga) West African Craton. The study area is located in the interference zone between N-S and NE--SW-trending craton-scale shear zones, formed during the Eburnean orogeny (2.15-2.00 Ga). High-grade metamorphic domains are separated from low-grade greenstone belts by high-strain zones, including early thrusts, extensional detachments and late-stage strike-slip shear zones. Paragneisses sporadically preserve high-pressure, low-temperature (HP-LT) relicts, formed at the transition between the blueschist facies and the epidote-amphibolite sub-facies (10.0-14.0 kbar, 520-600 °C), and represent a low (~15 °C km-1) apparent geothermal gradient. Migmatites record metamorphic conditions at the amphibolite-granulite facies transition. They reveal a clockwise pressure-temperature-time (P-T-t) path characterized by melting at pressures over 10.0 kbar, followed by decompression and heating to peak temperatures of 750 °C at 5.0-8.0 kbar, which fit a 30 °C km-1 apparent geotherm. A regional amphibolite facies metamorphic overprint is recorded by rocks that followed a clockwise P-T-t path, characterized by peak metamorphic conditions of 7.0-10.0 kbar at 550-680 °C, which match a 20-25 °C km-1 apparent geotherm. These P-T conditions were reached after prograde burial and heating for some rock units, and after decompression and heating for others. The timing of anatexis and of the amphibolite facies metamorphic overprint is constrained by in-situ U-Pb dating of monazite crystallization at 2138 ± 7 and 2130 ± 7 Ma respectively. The new data set challenges the interpretation that metamorphic breaks in the West African Craton are due to diachronous Birimian ‘basins’ overlying a gneissic basement. It suggests that the lower crust was exhumed along reverse, normal and transcurrent shear zones and juxtaposed against shallow crustal slices during the Eburnean orogeny. The craton in NW Ghana is made of distinct fragments with contrasting tectono-metamorphic histories. The range of metamorphic conditions and the sharp lateral metamorphic gradients are inconsistent with ‘hot orogeny’ models proposed for many Precambrian provinces. These findings shed new light on the geodynamic setting of craton assembly and stabilization in the Paleoproterozoic. It is suggested that the metamorphic record of the West African Craton is characteristic of Paleoproterozoic plate tectonics and illustrates a transition between Archean and Phanerozoic orogens.
DS201701-0012
2016
Ganne, J.Ganne, J., Feng, X., Rey, P., De Andrade, V.Statistical petrology reveals a link between supercontinents cycle and mantle global climate.American Mineralogist, Vol. 101, pp. 2768-2773.MantleGeostatistics

Abstract: The breakup of supercontinents is accompanied by the emplacement of continental flood basalts and dike swarms, the origin of which is often attributed to mantle plumes. However, convection modeling has showed that the formation of supercontinents result in the warming of the sub-continental asthenospheric mantle (SCAM), which could also explain syn-breakup volcanism. Temperature variations during the formation then breakup of supercontinents are therefore fundamental to understand volcanism related to supercontinent cycles. Magmatic minerals record the thermal state of their magmatic sources. Here we present a data mining analysis on the first global compilation of chemical information on magmatic rocks and minerals formed over the past 600 million years: a time period spanning the aggregation and breakup of Pangea, the last supercontinent. We show that following a period of increasingly hotter Mg-rich magmatism with dominant tholeiitic affinity during the aggregation of Pangea, lower-temperature minerals crystallized within Mg-poorer magma with a dominant calc-alkaline affinity during Pangea disassembly. These trends reflect temporal changes in global mantle climate and global plate tectonics in response to continental masses assembly and dispersal. We also show that the final amalgamation of Pangea at ~300 Myr led to a long period of lithospheric collapse and cooling until the major step of Pangea disassembly started at ~125 Myr. The geological control on the geosphere magma budget has implications on the oxidation state and temperature of the Earth’s outer envelopes in the Phanerozoic and may have exerted indirect influence on the evolution of climate and life on Earth.
DS201706-1070
2017
Ganne, J.Ganne, J., Feng, X.Primary magmas and mantle temperatures through time.Geochemistry, Geophysics, Geosystems: G3, Vol. 18, pp. 872-888.Mantlegeothermometry

Abstract: Chemical composition of mafic magmas is a critical indicator of physicochemical conditions, such as pressure, temperature, and fluid availability, accompanying melt production in the mantle and its evolution in the continental or oceanic lithosphere. Recovering this information has fundamental implications in constraining the thermal state of the mantle and the physics of mantle convection throughout the Earth's history. Here a statistical approach is applied to a geochemical database of about 22,000 samples from the mafic magma record. Potential temperatures (Tps) of the mantle derived from this database, assuming melting by adiabatic decompression and a Ti-dependent (Fe2O3/TiO2?=?0.5) or constant redox condition (Fe2+/?Fe?=?0.9 or 0.8) in the magmatic source, are thought to be representative of different thermal “horizons” (or thermal heterogeneities) in the ambient mantle, ranging in depth from a shallow sublithospheric mantle (Tp minima) to a lower thermal boundary layer (Tp maxima). The difference of temperature (?Tp) observed between Tp maxima and minima did not change significantly with time (~170°C). Conversely, a progressive but limited cooling of ~150°C is proposed since ~2.5 Gyr for the Earth's ambient mantle, which falls in the lower limit proposed by Herzberg et al. [2010] (~150-250°C hotter than today). Cooling of the ambient mantle after 2.5 Ga is preceded by a high-temperature plateau evolution and a transition from dominant plumes to a plate tectonics geodynamic regime, suggesting that subductions stabilized temperatures in the Archaean mantle that was in warming mode at that time.
DS201810-2317
2018
Ganne, J.Ganne, J., Feng, X.Magmatism: a crustal and geodynamic perspective.Journal of Structual Geology, Vol. 11, pp. 329-335.Mantlemagmatism

Abstract: The Earth's continental crust constitutes a major interface between the inner and outer envelops of the planet, controlling the differentiation of magmas produced in the mantle and their transfer to the surface. This close link facilitates the use of different chemical proxies to qualitatively unravel the crustal thickness related to fossil magmatic systems based on the message carried by magmas. This paper aims to bridge different results of statistical petrology, recently obtained at different scales of observation, in a global geodynamic model. Statistical analyses applied to a large multidimensional database of magmatic rocks show that crustal thickness could actually exert a first-order control on the composition of magmas, which become more calc-alkaline and comparatively less tholeiitic with increasing crustal thickness. Using this correlation, we document the progressive build-up of a thick (>40?km) Jurassic to Cretaceous accretionary belt along the Circum-Pacific Orogenic Belts (CPOB) that bounded the Panthalassa Ocean. The destruction of this thick belt started at ca. 125 Ma and was initially recorded by the thinnest magmatic systems hosting amphibole-bearing magma. Thinning of the CPOB became widespread in the northern regions of western America and in the western Pacific after ca. 75 Ma, possibly in response to oceanic plate segmentation, which triggered slab rollback and overriding plate extension. This chemical evolution is superimposed on a more global evolution of magma controlled by the temperature of the mantle that has gradually decreased since 200 Ma. Although the relative contribution of crust vs mantle cooling in the chemical signature of magmatic rocks should be further explored in the future, our results offer a new global perspective of the magmatic history of Pangea, the last supercontinent.
DS200512-0312
2005
Gannicott, R.Gannicott, R.Aber Diamond Corporation - charting its own unique course in response to its unique position.CIM Mining Rocks April 24-27th. Toronto Annual Meeting, Paper# 1923 AbstractCanada, Northwest TerritoriesNews item - Aber Diamond
DS200612-0426
2006
Gannicott, R.Gannicott, R.Joint ventures: diamond mines and jewellers.Prospectors and Developers Association of Canada, March 1p. abstractCanada, Northwest TerritoriesEconomics
DS200612-0427
2006
Gannicott, R.Gannicott, R.Strategy to grow a diamond mining company.SEG 2006 Conference, Wealth Creation in the Minerals Industry, May 14-16, Keystone Colorado USA, Abtract Volume p. 27. ( 1p.)Canada, Northwest TerritoriesMining methods - Diavik
DS201012-0217
2010
Gannicott, R.Gannicott, R.A diamond company's ride through the economic turmoil.PDAC 2010, March 8, abstractGlobalHarry Winston Diamond Corporation
DS2001-0353
2001
Gannicott, R.A.Gannicott, R.A.Canadian diamonds, baby-boomers and the American economy: a unique resource opportunity.Prospectors and Developers Association of Canada (PDAC) 2001, 1p. abstractGlobalDiamond - exploration brief overview, Investor - economics
DS201810-2336
2018
Ganno, S.Kankeu, B., Greiling, R.O., Nzenti, J.P., Ganno, S., Danguene, P.Y.E., Basshahak, J., Hell, J.V.Contrasting Pan-African structural styles at the NW margin of the Congo shield in Cameroon.Journal of African Earth Sciences, Vol. 146, pp. 28-47.Africa, Camerooncraton

Abstract: Field, microstructural, and anisotropy of magnetic susceptibility (AMS, magnetic fabrics) studies assessed the Pan-African deformational history and strain geometry at the southern margin of the Central African Fold Belt (CAFB) against the older, cratonic basement of the Congo Shield (CS). Reflected light microscopy and thermomagnetic studies supported the identification of magnetic minerals. Data cover a low angle thrust margin (Mbengis-Sangmelima area) in the east and high angle shear zones cutting the margin (Kribi area) in the west, at the Atlantic coast. In the CS basement units, magnetic anisotropy is generally higher than in the low grade Pan-African units. In the latter, early D1/D2 shortening produced a flat-lying magnetic foliation parallel with the regional trend of the belt, a shallow magnetic lineation, and mostly oblate fabrics. Subsequent D3 deformation is only of local importance in the Mbengis-Sangmelima area. The magnetic lineation shows distinct maxima in NNE-SSW direction, parallel with the low angle tectonic transport direction. In the Kribi area, the NNE-SSW trending Kribi-Campo shear zone (KCSZ) affected both older rocks and Pan-African high grade metapelites of the Yaoundé unit together with their basal thrust. The early planar fabric (S1) was overprinted during D2 folding under relatively high T conditions, and subsequent D3 wrenching. Magnetic fabrics document a progressive change from oblate towards prolate ellipsoids towards the KCSZ. Magnetic foliations with medium to steep dips curve into the N-S to NE-SW orientation of the KCSZ, lineations follow the same trend with shallow to medium plunges. This fabric implies that the KCSZ is a Pan-African strike-slip shear zone with a subordinate component of compression. Strike-slip tectonics in the west (KCSZ) and thrusting in the east imply N-S to NE-SW convergence during Pan-African terrane assembly against the present northern margin of the CS. In addition, the KCSZ may separate the CS from the São Francisco Craton in Brazil and thus be the northern part of a link connecting the CAFB to the West Congo Belt in the south. This putative Pan-African link separated the São Francisco Craton from the Congo Shield prior to Mesozoic Gondwana break-up.
DS2002-0229
2002
GannounBurton, K.W., Gannoun, Birck, Allegre, Schiano,AlardThe compatibility of rhenium and osmium in natural olivine and their behaviour during mantle melting...Earth and Planetary Science Letters, Vol.198,1-2,pp.63-76., Vol.198,1-2,pp.63-76.MantleMineralogy - olivine, Basalt genesis
DS2002-0230
2002
GannounBurton, K.W., Gannoun, Birck, Allegre, Schiano,AlardThe compatibility of rhenium and osmium in natural olivine and their behaviour during mantle melting...Earth and Planetary Science Letters, Vol.198,1-2,pp.63-76., Vol.198,1-2,pp.63-76.MantleMineralogy - olivine, Basalt genesis
DS1998-0463
1998
Gannoun, A.Gannoun, A., Birck, J.L., Bourdon, B., Allegre, C.J.Re Os systematics in orogenic peridotite massifs and contraints on the petrogenesis of pyroxenites.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 496-7.Morocco, Spain, FranceUltramafics, Deposit - Beni Bouzra, Ronda, Lherz
DS200512-0008
2005
Gannoun, A.Alard, O., Luguet, A., Pearson, N.J., Griffin, W.L., Lorand, J.P., Gannoun, A., Burton, K.W., O'Reilly, S.Y.In situ Os isotopes in abyssal peridotites bridge the isotopic gap between MORBS and their source mantle.Nature, Vol. 436, No. 7053, Aug. 18, pp. 1005-1108.MantleGeochronology
DS201112-0416
2011
Gannoun, A.Harvey, J., Dale, C.W., Gannoun, A., Burton, K.W.Osmium mass balance in peridotite and the effects of mantle derived sulphides on basalt petrogenesis.Geochimica et Cosmochimica Acta, Vol. 75, 9, pp. 5574-5596.United States, New Mexico, Colorado PlateauKilbourne
DS201504-0199
2015
Gannoun, A.Gannoun, A., Burton, K.W., Barfod, D.N., Schiano, P., Vlastelic, I., Halliday, A.N.Resolving mantle and magmatic processes in basalts from the Cameroon volcanic line using the Re-Os isotopic system.Lithos, Vol. 224-5, pp. 1-12.Africa, CameroonAlkaline rocks, basalts
DS201801-0039
2017
Gannoun, A.Moyen, J-F., Paquette, J.L., Ionov, D.A., Gannoun, A., Korsakov, A.V., Golovin, A.V., Moine, B.N.Paleoproterozoic rejuvenation and replacement of Archean lithosphere: evidence from zircon U-Pb dating and Hf isotopes in crustal xenoliths at Udachnaya, Siberian craton.Earth and Planetary Science Letters, Vol. 458, 1, pp. 149-159.Russiadeposit - Udachnaya

Abstract: Cratons represent the oldest preserved lithospheric domains. Their lithosphere (lithospheric mantle welded to overlying Precambrian crystalline basement) is considered to be particularly robust and long-lived due to the protecting presence of buoyant and rigid “keels” made up of residual harzburgites. Although the cratons are mostly assumed to form in the Archaean, the timing of their formation remains poorly constrained. In particular, there are very few datasets describing concurrently the age of both the crustal and mantle portions of the lithosphere. In this study, we report new U-Pb ages and Hf isotope compositions for zircons in crustal xenoliths from the Udachnaya kimberlite in the central Siberian craton; this dataset includes samples from both the upper and lower portions of the crust. The zircon ages agree well with model melt-extraction Re-Os ages on refractory peridotite xenoliths from the same pipe; taken together they allow an integrated view of lithosphere formation. Our data reveal that the present day upper crust is Archaean, whereas both the lower crust and the lithospheric mantle yield Paleoproterozoic ages. We infer that the deep lithosphere beneath the Siberian craton was not formed in a single Archaean event, but grew in at least two distinct events, one in the late Archaean and the other in the Paleoproterozoic. Importantly, a complete or large-scale delamination and rejuvenation of the Archaean lower lithosphere (lower crust and lithospheric mantle) took place in the Paleoproterozoic. This further demonstrates that craton formation can be a protracted, multi-stage process, and that the present day crust and mantle may not represent complementary reservoirs formed through the same tectono-magmatic event. Further, deep cratonic lithosphere may be less robust and long living than often assumed, with rejuvenation and replacement events throughout its history.
DS201808-1775
2017
Gannoun, A.Paquette, J.L., Ionov, D.A., Agashev, A.M., Gannoun, A., Nikolenko, E.I.Age, provenance and Precambrian evolution of the Anabar shield from U Pb and Lu Hf isotope dat a on detrital zircons, and the history of the northern and central Siberian craton.Precambrian Research, Vol. 301, pp. 134-144.Russiacraton

Abstract: The Anabar shield in northern Siberia is one of the world’s least studied Precambrian areas, and provides a ‘window’ into the crustal basement of the central and northern Siberian craton. We report U-Pb and Hf isotope data for detrital zircons sampled in a profile across its major structural units. They define a U-Pb age range from 1.8 to 3.4 Ga with three main periods: 1.8-2.0 Ga, 2.4-2.8 Ga and 3.0-3.4 Ga. The oldest zircons yield super-chondritic eHf(t) implying that the parental magmas of their source rocks were juvenile, i.e. formed from depleted mantle (DM). Thus, the crustal basement of the Anabar shield, and probably the whole central and northern Siberian craton, started to form in the mid-Paleoarchean, and included no recycled crust. Zircons with 2.5-2.7 Ga ages define two eHf(t) intervals. One is super-chondritic (+2 to +7) implying juvenile sources, the other is sub-chondritic (-3 to -12) indicative of recycled crust, probably formed at 3.2-3.4 Ga, in magma sources. Nearly all 1.8-2.0 Ga zircons have sub-chondritic eHf(t) (-2 to -29) implying derivation from sources dominated by recycled crust formed at ~2.6 Ga and ~3.4 Ga and little or no juvenile addition. These events accompanied amalgamation of the entire craton by welding of Archean domains. The Bekelekh unit of the Daldyn series has the highest proportion of ~2.6 Ga zircons and may be the oldest ‘nucleus’ of the Anabar shield, whereas the Kilegur unit of the same series is essentially Proterozoic (1.95 Ga). The largest amount of 3.1-3.4 Ga zircons, as well as common 2.6-2.7 Ga zircons, occur in the Ambardakh unit of the Upper Anabar series. Our data suggest alternation of areas with dominant ages of 1.95 Ga and ~2.6 Ga, with the younger zircons coming from granites and granulites, and the older ones from gneisses. They show no evidence for significant ages differences for the Anabar and Olenek provinces. The final amalgamation of the entire Siberian craton by welding of Archean blocks, may have taken place at around 1954 ± 6 Ma.
DS1991-0409
1991
Gans, P.B.Dumitru, T.A., Gans, P.B., Foster, D.A., Miller, E.L.Refrigeration of the western Cordilleran lithosphere during Laramide shallow angle subductionGeology, Vol. 19, No. 11, November pp. 1145-1148CordilleraSubduction, Tectonics
DS1998-0464
1998
Gans, P.B.Gans, P.B., Bohrson, W.A.Suppression of volcanism during rapid extension in the Basin and Rangeprovince, United StatesScience, Vol. 279, No. 5347, Jan. 2, pp. 66-68Nevada, Basin and Rangevolcanism., tectonics
DS200512-0910
2005
Gans, P.B.Root, D.B., Hacker, B.R., Gans, P.B., Ducea, E.A., Eide, J.L.Discrete ultrahigh prssure domains in the Western Gneiss region, Norway: implications for formation and exhumation.Journal of Metamorphic Geology, Vol. 23, 1, pp. 45-61.Europe, NorwayUHP
DS200912-0275
2009
Gans, P.B.Hacker, B.R., Wallis, S.R., McWilliams, M.O., Gans, P.B.40 Ar 39AR constraints on the tectonic history and architecture of the ultrahigh pressure Sulu orogen.Journal of Metamorphic Geology, Vol. 27, 9, pp. 827-844.ChinaUHP
DS1960-1107
1969
Ganster, M.Ganster, M., Stearns, P.G.Configuration and Source of Anomalous Magnetic Field Near Gordonsville in Smith County, Tennessee.Tennessee Academy of Science Journal, Vol. 44, No. 2, P. 49, (abstract.).United States, Tennessee, Central StatesBlank
DS201611-2109
2016
Ganti, V.Ganti, V., Von Hagke, C., Scherler, D., Lamb, M.P., Fischer, W.W., Avouac, J-P.Time scale bias in erosion rates of glaciated landscapes.Science Advances, Vol. 2, 10, 3p.GlobalGlaciology

Abstract: Deciphering erosion rates over geologic time is fundamental for understanding the interplay between climate, tectonic, and erosional processes. Existing techniques integrate erosion over different time scales, and direct comparison of such rates is routinely done in earth science. On the basis of a global compilation, we show that erosion rate estimates in glaciated landscapes may be affected by a systematic averaging bias that produces higher estimated erosion rates toward the present, which do not reflect straightforward changes in erosion rates through time. This trend can result from a heavy-tailed distribution of erosional hiatuses (that is, time periods where no or relatively slow erosion occurs). We argue that such a distribution can result from the intermittency of erosional processes in glaciated landscapes that are tightly coupled to climate variability from decadal to millennial time scales. In contrast, we find no evidence for a time scale bias in spatially averaged erosion rates of landscapes dominated by river incision. We discuss the implications of our findings in the context of the proposed coupling between climate and tectonics, and interpreting erosion rate estimates with different averaging time scales through geologic time.
DS201505-0250
2015
Ganuza, M.L.Ferracutti, G.R., Gargiulo, M.F., Ganuza, M.L., Bjerg, E.A., Castro, S.M.Determination of the spinel group end-members based on electron microprobe analyses.Mineralogy and Petrology, Vol. 109, 2, pp. 153-160.TechnologyGeochronology
DS2001-1061
2001
Ganvir, D.V.Shasidharan, K., Ganvir, D.V.Search for kimberlite lamproite in parts of Chanrapur Garchiroli and Nanded districts, Maharashtra.India Geological Survey Records, No. 133, 6, p. 37-42.IndiaNews item, exploration
DS200612-1225
2001
Ganvir, D.V.Sashidharan, K., Ganvir, D.V., Mohanty, A.K.Search for kimberlites and lamproites in the western part of the Bastar Craton, Maharashtra.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 629-634.India, MaharashtraDiamond exploration - geochemistry comparison Monastery
DS201412-0263
2014
Ganz, M.Ganz, M.The state of the industry as 2014 begins.Hayashalom Magazine, January No. 213, pp. 8-11.GlobalEconomics
DS201412-0264
2014
Ganz, M.Ganz, M.The GIA has become our achilles heel. Slow documentation.Hayashalom Magazine, No. 215, pp. 8-11.GlobalGIA and documents
DS200912-0860
2009
GaoZheng, J.P., Griffin, W.L., O'Reilly, S.Y., Sun, M., Zheng, S., Pearson, N., Gao, Yu, Su, Tang, Liu, WuAge and composition of granulite and pyroxenite xenoliths in Hannuoba basalts reflect Paleogene underplating beneath the North Chin a craton.Chemical Geology, Vol. 264, 1-4, pp. 266-280.ChinaXenoliths
DS201608-1441
2016
Gao, B.Song, Z., Lu, T., Tang, S., Ke, J., Su, J., Gao, B., Bi, L., Wang, D.Identification of colourless HPHT grown synthetic diamonds from Shandong China.The Journal of Gemmology, Vol. 35, 2, pp. 14-147.ChinaSynthetics
DS200812-0383
2008
Gao, C.Gao, C., Liu, Y.Moissanite bearing carbonatite xenoliths from Cenozoic basalt, North China: products of ancient oceanic crust subduction.Goldschmidt Conference 2008, Abstract p.A292.ChinaCarbonatite
DS200812-0680
2008
Gao, C.Liu, Y., Gao, S., Gao, C., Zong, K.Recycling of lower continental crust in the Trans-North Chin a Orogen: evidence from zircon dating of mantle composite xenoliths.Goldschmidt Conference 2008, Abstract p.A563.ChinaCraton
DS201112-0343
2011
Gao, C.Gao, C.Surficial geology mapping and till sampling in the Chapleau area, northern Ontario. ( Kapuskasing Structual Zone ) and potential for kimberlite.Ontario Summary of Field Work and Other Activities, Ontario Open File 6270, pp.20-1-20-5.Canada, OntarioGeochemistry
DS201212-0227
2012
Gao, C.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
DS201212-0627
2012
Gao, C.Schmidt, M.W., Rohrbach, A., Gao, C., Connolly, J.A.D.The role of redox equilibration temperatures during carbon transfer in the mantle and the stability of carbides in the mantle.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleRedox
DS201501-0030
2014
Gao, C.Schmidt, M.W., Gao, C., Golubkova, A., Rohrbach, A., Connolly, J.A.D.Natural moissanite ( SiC) - a low temperature mineral formed from highly fractionated ultra-reducing COH-fluids.Progress in Earth and Planetary Science, Vol. 1, pp. 27-Moissanite
DS201605-0837
2016
Gao, C.Gao, C., Crabtree, D.C., Dyer, R.D.Indicator mineral and geochemistry dat a for a till and alluvium sampling survey in the McFaulds Lake ( Ring of Fire) area, northern Ontario. Mentions KIMS.Ontario Geological Survey Report and Data, Report 6309, Data release 322.Canada, OntarioGeochemistry - KIMS
DS201703-0406
2017
Gao, C.He, D., Liu, Y., Gao, C., Chen, C., Hu, Z., Gao, S.SiC dominated ultra-reduced mineral assemblage in carbonatitic xenoliths from the Dalihu basalt, Inner Mongolia, China.American Mineralogist, Vol. 102, pp. 312-320.China, MongoliaCarbonatite

Abstract: SiC and associated ultra-reduced minerals were reported in various geological settings, however, their genesis and preservation mechanism are poorly understood. Here, we reported a SiC-dominated ultra-reduced mineral assemblage, including SiC, TiC, native metals (Si, Fe, and Ni) and iron silicide, from carbonatitic xenoliths in Dalihu, Inner Mongolia. All minerals were identified in situ in polished/thin sections. SiC is 20-50 µm in size, blue to colorless in color, and usually identified in the micro-cavities within the carbonatitic xenolith. Four types of SiC polytypes were identified, which are dominated by ß-SiC (3C polytype) and 4H polytype followed by 15R and 6H. These SiC are featured by 13C-depleted isotopic compositions (d13C = -13.2 to -22.8‰, average = -17.7‰) with obvious spatial variation. We provided a numerical modeling method to prove that the C isotopic composition of the Dalihu SiC can be well-yielded by degassing. Our modeling results showed that degassing reaction between graphite and silicate can readily produce the low d13C value of SiC, and the spatial variations in C isotopic composition could have been formed in the progressive growth process of SiC. The detailed in situ occurring information is beneficial for our understanding of the preservation mechanism of the Dalihu ultra-reduced phase. The predominant occurrence of SiC in micro-cavities implies that exsolution and filling of CO2 and/or CO in the micro-cavities during the diapir rising process of carbonatitic melt could have buffered the reducing environment and separated SiC from the surrounding oxidizing phases. The fast cooling of host rock, which would leave insufficient time for the complete elimination of SiC, could have also contributed to the preservation of SiC.
DS202009-1676
2020
Gao, C.Zheng, H., Chen, H., Wu, C., Jiang, H., Gao, C., Kang, Q., Yang, C., Wang, D., Lai, C-K.Genesis of the supergiant Huayangchuan carbonatite-hosted uranium polymetallic deposit in the Qinling orogen, central China.Gondwana Research, Vol. 86, pp. 250-265.ChinaREE

Abstract: The newly-discovered supergiant Huayangchuan uranium (U)-polymetallic deposit is situated in the Qinling Orogen, Central China. The deposit contains economic endowments of U, Nb, Pb, Se, Sr, Ba and REEs, some of which (e.g., U, Se, and Sr) reaching super-large scale. Pyrochlore, allanite, monazite, barite-celestite and galena are the major ore minerals at Huayangchuan. Uranium is mainly hosted in the primary mineral of pyrochlore, and the mineralization is mainly hosted in or associated with carbonatite dikes. According to the mineral assemblages and crosscutting relationships, the alteration/mineralization at Huayangchuan comprises four stages, i.e., pegmatite REE mineralization (I), main mineralization (II), skarn mineralization (III) and post-ore alteration (IV). Coarse-grained euhedral allanite is the main Stage I REE mineral, and the pegmatite-hosted REE mineralization (ca. 1.8 Ga) occurs mostly in the shallow-level of northwestern Huayangchuan, corresponding to the Paleoproterozoic Xiong'er Group volcanic rocks (1.80-1.75 Ga) in the southern margin of North China Block. Carbonatite-hosted Stage II mineralization contributes to the majority of U-Nb-REE-Ba-Sr resources, and is controlled by the Huayangchuan Fault. Stage II mineralization can be further divided into the sulfate mineralization (barite-celestite) (II-A), alkali-rich U mineralization (aegirine-augite + pyrochlore + uraninite + uranothorite) (II-B) and REE (allanite + monazite + chevkinite)-U (pyrochlore + uraninite) mineralization (II-C) substages. Stage II mineralization may have occurred during the Late Triassic Mianlue Ocean closure. Skarn mineralization contributed to the majority of Pb and minor U-REE (uraninite-allanite) resources at Huayangchuan, and is spatially associated with the Late Cretaceous-Early Jurassic (Yanshanian) Huashan and Laoniushan granites. We suggested that hydrothermal fluids derived from the Laoniushan and Huashan granites may have reacted with the Triassic carbonatites, and formed the Huayangchuan Pb skarn mineralization. The mantle-derived Triassic carbonatites may have been fertilized by the U-rich subducting oceanic sediments, and were further enriched through reacting with the Proterozoic U-REE-rich pegmatite wallrocks at Huayangchuan. Ore-forming elements were likely transported in metal complexes (F-, and ), and deposited with the dilution of the complex concentration. This may have formed the distinct vertical mineralization zoning, i.e., sodic fenite-related alkali-U mineralization at depths and potassic fenite-related REE-U mineralization at shallow level.
DS202012-2258
2020
Gao, C.Zheng, H., Chen, H., Wu, C., Jiang, H., Gao, C., Kang, Q., Yang, C., Wang, D., Lai, C-k.Genesis of the supergiant Huayanchuan carbonatite-hosted uranium-plymetallic deposit in the Qinling Orogen, central China.Gondwana Research, Vol. 86, pp. 250-265. pdfChinadeposit - Huayangchuan

Abstract: The newly-discovered supergiant Huayangchuan uranium (U)-polymetallic deposit is situated in the Qinling Orogen, Central China. The deposit contains economic endowments of U, Nb, Pb, Se, Sr, Ba and REEs, some of which (e.g., U, Se, and Sr) reaching super-large scale. Pyrochlore, allanite, monazite, barite-celestite and galena are the major ore minerals at Huayangchuan. Uranium is mainly hosted in the primary mineral of pyrochlore, and the mineralization is mainly hosted in or associated with carbonatite dikes. According to the mineral assemblages and crosscutting relationships, the alteration/mineralization at Huayangchuan comprises four stages, i.e., pegmatite REE mineralization (I), main mineralization (II), skarn mineralization (III) and post-ore alteration (IV). Coarse-grained euhedral allanite is the main Stage I REE mineral, and the pegmatite-hosted REE mineralization (ca. 1.8 Ga) occurs mostly in the shallow-level of northwestern Huayangchuan, corresponding to the Paleoproterozoic Xiong'er Group volcanic rocks (1.80-1.75 Ga) in the southern margin of North China Block. Carbonatite-hosted Stage II mineralization contributes to the majority of U-Nb-REE-Ba-Sr resources, and is controlled by the Huayangchuan Fault. Stage II mineralization can be further divided into the sulfate mineralization (barite-celestite) (II-A), alkali-rich U mineralization (aegirine-augite + pyrochlore + uraninite + uranothorite) (II-B) and REE (allanite + monazite + chevkinite)-U (pyrochlore + uraninite) mineralization (II-C) substages. Stage II mineralization may have occurred during the Late Triassic Mianlue Ocean closure. Skarn mineralization contributed to the majority of Pb and minor U-REE (uraninite-allanite) resources at Huayangchuan, and is spatially associated with the Late Cretaceous-Early Jurassic (Yanshanian) Huashan and Laoniushan granites. We suggested that hydrothermal fluids derived from the Laoniushan and Huashan granites may have reacted with the Triassic carbonatites, and formed the Huayangchuan Pb skarn mineralization. The mantle-derived Triassic carbonatites may have been fertilized by the U-rich subducting oceanic sediments, and were further enriched through reacting with the Proterozoic U-REE-rich pegmatite wallrocks at Huayangchuan. Ore-forming elements were likely transported in metal complexes (F-, and ), and deposited with the dilution of the complex concentration. This may have formed the distinct vertical mineralization zoning, i.e., sodic fenite-related alkali-U mineralization at depths and potassic fenite-related REE-U mineralization at shallow level.
DS200812-0384
2008
Gao, E-G.Gao, E-G., Liu, H., Liu, L-F.The origin and tectonic frame of the Dabie Shan orogenic belt: constraints from geophysical data.Goldschmidt Conference 2008, Abstract p.A293.ChinaUHP
DS1996-0478
1996
Gao, H.Gao, H., Wang, J., Zhao, P.The updated kriging variance and optimal sample designMathematical Geology, Vol. 28, No. 3, pp. 295-313GlobalComputer, Program -kriging variance, sample design
DS2001-0354
2001
Gao, J.Gao, J., Klemd, R.Primary fluids entrapped at blueschist to eclogite transition: evidence from the Tainshan meta subductionContributions to Mineralogy and Petrology, Vol. 142, No. 1, Oct. pp. 1-14.China, NorthwestMineral chemistry, Subduction
DS2002-0862
2002
Gao, J.Klemd, R., Schroter, F.C., Will, T.M., Gao, J.P-T evolution of glauco phaneomphacite bearing HP - LT rocks in the eastern Tien Shan Orogen: Alpine type ..Journal of Metamorphic Geology, Vol. 20, No. 2, pp. 239-54.China, northwestTectonics - evidence, Ultrahigh pressure, UHP
DS2003-0436
2003
Gao, J.Gao, J., Klemd, R.Formation of HP LT rocks and their tectonic implications in the western TainshanLithos, Vol. 66, 1-2, Jan. pp. 1-22.ChinaGeochemistry
DS2003-0437
2003
Gao, J.Gao, J., Klemd, R.Formation of HP Lt rocks and their tectonic implications in the western TianshanLithos, Vol. 66, 3-4, January, pp. 1-22.ChinaMineral chemistry, Geochronology
DS2003-0438
2003
Gao, J.Gao, J., Klemd, R.Formation of HP LT rocks and their tectonic implications in the Western TienshanLithos, Vol. 66, 1-2, pp. 1-22.ChinaUHP - ultrahigh pressure
DS200412-0604
2003
Gao, J.Gao, J., Klemd, R.Formation of HP Lt rocks and their tectonic implications in the western Tian Shan Orogen, NW China: geochemical and age constrainLithos, Vol. 66, 3-4, January, pp. 1-22.ChinaMineral chemistry, Geochronology
DS200612-0715
2006
Gao, J.Klemd, R., Gao, J., John, T.Trace element enriched fluids released during slab dehydration: implications for oceanic slab mantle wedge transfer.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 22. abstract only.MantleSubduction
DS201112-0527
2011
Gao, J.Klemd, R., Scherer, J.E.E., Rondenay, S., Gao, J.Changes in dip of subducted slabs at depth: petrological and geochronological evidence from HP-UHP rocks (Tianshan, NW China).Earth and Planetary Science Letters, Vol. 310, 1-2, pp. 9-20.ChinaUHP
DS201703-0403
2017
Gao, J.Gao, J., Niu, J., Qin, S., Wu, X.Ultradeep diamonds originate from deep subducted sedimentary carbonates.Science China Earth Sciences, Vol. 60, 2, pp. 207-217.TechnologySubduction

Abstract: Diamonds are renowned as the record of Earth’s evolution history. Natural diamonds on the Earth can be distinguished in light of genetic types as kimberlitic diamonds (including peridotitic diamonds and eclogitic diamonds), ultrahigh-pressure metamorphic diamonds and ophiolitic diamonds. According to the inclusion mineralogy, most diamonds originated from continental lithospheric mantle at depths of 140-250 km. Several localities, however, yield ultradeep diamonds with inclusion compositions that require a sublithospheric origin (>~250 km). Ultradeep diamonds exhibit distinctions in terms of carbon isotope composition, N-concentration, mineral inclusions and so on. The present study provides a systematic compilation concerning the features of ultradeep diamonds, based on which to expound their genesis affinity with mantle-carbonate melts. The diamond-parental carbonate melts are proposed to be stemmed from the Earth’s crust through subduction of oceanic lithosphere. Ultradeep diamonds are classified into a subgroup attaching to kimberlitic diamonds grounded by formation mechanism, and present connections in respect of carbon origin to eclogitic diamonds, ultrahigh-pressure metamorphic diamonds and ophiolitic diamonds.
DS201706-1071
2016
Gao, J.Gao, J., Niu, J.J., Qin, S., Wu, X.Ultradeep diamonds originate from deep subducted sedimentary carbonates.Science China Earth Sciences, 12p. * engMantlesubduction, carbon cycle

Abstract: Diamonds are renowned as the record of Earth’s evolution history. Natural diamonds on the Earth can be distinguished in light of genetic types as kimberlitic diamonds (including peridotitic diamonds and eclogitic diamonds), ultrahigh-pressure metamorphic diamonds and ophiolitic diamonds. According to the inclusion mineralogy, most diamonds originated from continental lithospheric mantle at depths of 140-250 km. Several localities, however, yield ultradeep diamonds with inclusion compositions that require a sublithospheric origin (>~250 km). Ultradeep diamonds exhibit distinctions in terms of carbon isotope composition, N-concentration, mineral inclusions and so on. The present study provides a systematic compilation concerning the features of ultradeep diamonds, based on which to expound their genesis affinity with mantle-carbonate melts. The diamond-parental carbonate melts are proposed to be stemmed from the Earth’s crust through subduction of oceanic lithosphere. Ultradeep diamonds are classified into a subgroup attaching to kimberlitic diamonds grounded by formation mechanism, and present connections in respect of carbon origin to eclogitic diamonds, ultrahigh-pressure metamorphic diamonds and ophiolitic diamonds.
DS201707-1325
2016
Gao, J.Gao, J., Niu, J., Qin, S., Wu, X.Ultradeep diamonds originate from deep subducted sedimentary carbonates.Science China Earth Sciences, Vol. 60, 2, 3p.MantleUHP

Abstract: Diamonds are renowned as the record of Earth’s evolution history. Natural diamonds on the Earth can be distinguished in light of genetic types as kimberlitic diamonds (including peridotitic diamonds and eclogitic diamonds), ultrahigh-pressure metamorphic diamonds and ophiolitic diamonds. According to the inclusion mineralogy, most diamonds originated from continental lithospheric mantle at depths of 140–250 km. Several localities, however, yield ultradeep diamonds with inclusion compositions that require a sublithospheric origin (>~250 km). Ultradeep diamonds exhibit distinctions in terms of carbon isotope composition, N-concentration, mineral inclusions and so on. The present study provides a systematic compilation concerning the features of ultradeep diamonds, based on which to expound their genesis affinity with mantle-carbonate melts. The diamond-parental carbonate melts are proposed to be stemmed from the Earth’s crust through subduction of oceanic lithosphere. Ultradeep diamonds are classified into a subgroup attaching to kimberlitic diamonds grounded by formation mechanism, and present connections in respect of carbon origin to eclogitic diamonds, ultrahigh-pressure metamorphic diamonds and ophiolitic diamonds.
DS201809-2085
2018
Gao, J.Sharma, S.K., Chen, B., Gao, J., Lai, X.Micro-Raman investigations of diamond genesis during slab-mantle interaction.Goldschmidt Conference, 1p. AbstractMantlediamond genesis

Abstract: Magnesite is proposed to be a major oxidized carbon storage phase in the mantle due to its wide P-T range of stability [1-2]. The presence of magnesite in the Earth's interior will depend on the redox state of the Earth's interior. Large part of the deep mantel is considered to be significantly reduced with considerable amount of FeO dispersed in rocks [3]. During slab-mantle interaction, subducted carbonates in the slab will undergo redox reactions with metallic Fe. However, the mechanism of this interaction is not well understood. In order to understand diamond genesis during the slabmantle interactions, we have conducted high-pressure and high-temperature experiments in a 2000-ton multi-anvil highpressure press on samples containing MgCO3 and iron foils (50 µm thick) in BN capsules. The samples under pressures from 10 to 16 GPa were heated to 1200-1700 K. The samples were quenched under pressure and the quenched samples were polished and then analyzed with multi-wavelength micro-Raman spectrometers using 785, 514.5 and 532 nm laser excitations. Micro-Raman investigations show that the iron foils reduce MgCO3 to various sp2 carbon phases, mainly graphite, followed by the transformation to diamond upon long-duration heating. The transformation to diamond is driven by the temperature. For example, in the Run number PL066 with staring material containing magnesite and two Fe foils heated to 1400 K at 10 GPa for 24 hrs, and quenched, the run products were [Mg,Fe]O, and diamond and graphite. The sample PL044 with staring material containing magnesite and three Fe foils heated to 1600 K at 14 GPa for 12 hrs, the run products were larger size (~10 µm) diamonds, iron carbide and small amount of graphite. Our results indicate that in slow subduction (T~1500 K) all carbonates will be converted in diamond and iron carbide. Under rapid subduction of the slab, the carbonate will survive and be carried to greater depth. The inclusions of [Mg,Fe]O in diamonds, however, do not necessarily indicate that this phase is of lower mantle origin.
DS201906-1340
2019
Gao, J.Qiao, X., Zhou, Z., Schwarz, D.T., Qi, L., Gao, J., Nong, P., Lai, M., Guo, K., Li, Y.Study of the differences in infrared spectra of emerald from different mining areas and the controlling factors.The Canadian Mineralogist, Vol. 57, pp. 65-79.Globalemerald genesis

Abstract: Natural emeralds from 11 mining areas were studied using an infrared spectrometer. The results showed different spectroscopic characteristics for emerald from different mine regions. Infrared absorption is mainly attributed to the vibration of Si-O lattice, channel water, alkaline cations, and molecules such as CO2, [Fe2(OH)4]2+, etc. Both near-infrared and mid-infrared spectra showed that the differences in band positions, intensities, and shapes are related to the mixed ratio of the two types of channel water. Accordingly, emerald and its mining regions can be divided into 3 types: H2O I, H2O II, and transition I-II. Furthermore, the study indicates that the relative amounts of the two different orientations of channel water molecules are mainly affected by the presence of (Mg + Fe)2+ in the host rock or in the mineralizing fluid. Therefore, the mineralization environment type (alkali-poor, alkali-rich, and transitional types) of emerald can be preliminarily identified from IR spectroscopy. This can be useful for determining the origin of emeralds.
DS1998-1300
1998
Gao, R.Schulze, A., Jiang, M., Ryberg, T., Gao, R.Survey yields dat a on unique metamorphic rock complex in ChinaEos, Vol. 79, No. 36, Sept. 8, p. 429, 433.ChinaGeophysics - seismics, Dabie Shan
DS2001-0684
2001
Gao, R.Li, P., Cui, J., Gao, R.Estimation of shortening between Siberian and Indian plates since the Early CretaceousJour. Asian Earth Sci., Vol. 20, No. 3, pp. 241-5.Russia, Siberia, IndiaTectonics - compression Himalayan Block
DS200512-0242
2005
Gao, R.Dong, S., Gao, R., Cong, B., Zhao, Z., Liu, X., Li, S., Huang, D.Crustal structure of the southern Dabie ultrahigh pressure orogen and Yangtze foreland from deep seismic reflection profiling.Terra Nova, Vol. 16, 6, Dec. pp. 319-324.ChinaUHP, tectonics
DS200812-0290
2008
Gao, R.Dong, S.W., Li, Q.S., Gao, R., Liu, F.T., Liu, X.C., Xue, H.M., Guan, Y.Moho mapping in the Dabie ultrahigh pressure collisional orogen, central China.American Journal of Science, Vol. 308, 4, pp. 517-528.ChinaUHP
DS1995-0579
1995
Gao, S.Gao, S., Wedepohl, K.H.The negative Eu anomaly in Archean sedimentary rocks: implications fordecomposition, age, importance graniteEarth and Planet. Science Letters, Vol. 133, pp. 81-94South Africa, Greenland, North America, Australia, ChinaArchean Eu signatures, Europium, Continental crust composition
DS1995-0580
1995
Gao, S.Gao, S., Zhang, B.R., Guo, X-M.Silurian Devonian provenance changes of South Qinling Basins: implicationfor accretion of Yangtze craton.Tectonophysics, Vol. 250, No. 1/3, Nov. 15, pp. 183-ChinaCraton, North China
DS1998-0465
1998
Gao, S.Gao, S., Zhang, B.R., Zhao, Z.D.How mafic is the lower continental crust?Earth and Planetary Science Letters, Vol. 161, No. 1-4, Sept. 1, pp. 101-118.MantleMagmatism
DS1999-0358
1999
Gao, S.Kern, H., Gao, S., Jin, S.Petrophysical studies on rocks from the Dabie ultrahigh pressure metamorphic belt: implications for compositionTectonophysics, Vol. 301, No. 3-4, Jan. 30, pp. 191-216.ChinaCrust - petrology, metamorphism
DS2000-0310
2000
Gao, S.Gao, S., Kern, H., Zhao, Z-B.Measured and calculated seismic velocities and densities for granulites from xenolith occurrencesJournal of Geophysical Research, Vol. 105, No.8, Aug. 10, pp.18965-76.ChinaCraton - North, Lower crustal sections
DS2001-0355
2001
Gao, S.Gao, S., Kern, H., Jin, Popp, Jin, Zhang, ZhangPoisson's ratio of eclogite: the role of retrogressionEarth and Planetary Science Letters, Vol. 192, No. 4, pp. 523-31.GlobalEclogite - geochemistry, Poisson ratio
DS2001-1076
2001
Gao, S.Silver, P., Gao, S.Anisotropic and discontinuity structure beneath southern AfricaSlave-Kaapvaal Workshop, Sept. Ottawa, 1p. abstractSouth AfricaGeophysics - seismics
DS2002-0087
2002
Gao, S.Ayers, J.C., Dunkle, S., Gao, S., Miller, C.F.Constraints on timing of peak and retrograde metamorphism in the Dabie Shan ultrahigh pressure metamorphic belt, east central China, using U Th PbChemical Geology, Vol.186,2-3, pp.315-31.ChinaUHP, Geochronology - dating of zircon and monazite
DS2002-0497
2002
Gao, S.Gao, 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
Gao, S.Gao, 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
DS2002-1773
2002
Gao, S.Zhang, H., Gao, S., Zhong, Z., Zhang, B., Zhang, L., Hu, S.Geochemical and Sr Nd Pb isotopic compositions of Cretaceous granitoids: constraintsChemical Geology, Vol. 186, 2-4, pp. 281-99.China, easternUHP, Dabie Shan area
DS2003-0820
2003
Gao, S.Ling, W., Gao, S., Zhang, B., Li, H., Liu, Y., Cheng, J.Neoproterozoic tectonic evolution of the northwestern Yangtze Craton, South China:Precambrian Research, Vol. 122, 1-4, pp.111-140.China, RodiniaTectonics
DS200412-0605
2003
Gao, S.Gao, S., Rudnick, R.L., Carlson, R.W.Removal of lithospheric mantle in the North Chin a Craton: Re Os isotopic evidence for coupled crust - mantle growth.Earth Science Frontiers, Vol. 10, 3, pp. 61-68. Ingenta 1035303167ChinaGeochronology
DS200412-1139
2003
Gao, S.Ling, W., Gao, S., Zhang, B., Li, H., Liu, Y., Cheng, J.Neoproterozoic tectonic evolution of the northwestern Yangtze Craton, South China: implications for amalgamation and break up ofPrecambrian Research, Vol. 122, 1-4, pp.111-140.China, RodiniaTectonics
DS200412-1164
2003
Gao, S.Liu, Y.,Gao, S., Liu, X., Chen, X., Zheng, W., Wang, X.Thermodynamic evolution of lithosphere of the North Chin a Craton: records from lower crust and upper mantle xenoliths from HannuChinese Science Bulletin, Vol. 48, 21, pp. 2371-77. Ingenta 1035395020ChinaGeothermometry
DS200412-1165
2004
Gao, S.Liu, Y., Gao, S., Yuan, H., Zhou, L., Liu, X., Wang, X., Hu, Z., Wang, L.U Pb zircon ages and Nd, Sr, and Pb isotopes of lower crustal xenoliths from North Chin a Craton: insights on evolution of lowerChemical Geology, Vol. 211, 1-2, Nov. 8, pp. 87-109.ChinaGeochronology
DS200412-1700
2004
Gao, S.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
DS200512-0313
2004
Gao, S.Gao, S., Rudnick, R.L., Yuan, H.L., Liu, X.M., Liu, Y.S., Xu, W.L., Ling, W.L., Ayers, K., Wang, X.C.,Wang, Q.H.Recycling lower continental crust in the North Chin a Craton.Nature, No. 7019, Dec. 16, pp. 892-896.ChinaSubduction
DS200512-0651
2005
Gao, S.Liu, Y., Gao, S., Lee, C.T.A., Hu, S., Liu, X.,Yuan, H.Melt peridotite interactions: links between garnet pyroxenite and high Mg# signature of continental crust.Earth and Planetary Science Letters, Vol. 234, pp. 39-57.MantleGeochemistry
DS200512-1078
2004
Gao, S.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
DS200612-0106
2006
Gao, S.Becker, H., Horan, M.F., Walker, R.J., Gao, S., Lorand, J-P., Rudnick, R.L.Highly siderophile element composition of the Earth's primitive upper mantle: constraints from new dat a on peridotite massifs and xenoliths.Geochimica et Cosmochimica Acta, Vol. 70, 17, pp. 4528-4550.MantleMineral chemistry
DS200612-0428
2006
Gao, S.Gao, S., Rudnick, R.L., Xu, W.L., Yuan, H.L., Hu, Z.C., Liu, X.M.Lithospheric evolution of the North Chin a Craton: evidence from high Mg adakitic rocks and their entrained xenoliths.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 193, abstract only.ChinaGeochemistry
DS200612-0830
2006
Gao, S.Liu, X., Gao, S., Ling, W., Yuan, H., Hu, Z.Identification of 3.5 Ga detrital zircons from Yangtze Craton in South Chin a and the implication for Archean crust evolution.Progress in Natural Science, Vol. 16, 6, June pp. 663-666.ChinaGeochronology
DS200612-1579
2006
Gao, S.Yuan, H.L., Gao, S., Rudnick, R.L., Jin, Z.M., Walker, R.J.Re Os evidence for age and origin of peridotites from the Dabie Sulu UHP belt.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 10. abstract only.ChinaUHP, geochronology
DS200612-1594
2006
Gao, S.Zhang, S-B., Zheng, Y-F., Wu, Y-B., Zhao, Z-F., Gao, S., Wu, F-Y.Zircon isotope evidence for >3.5 Ga continental crust in the Yangtze craton of China.Precambrian Research, in press,ChinaCrustal evolution, geochronology
DS200712-0347
2007
Gao, S.Gao, S., Rudnick, R.L., Xu, W-L., Yuan, Liu, Puchtel, Liu, Huang, WangRecycling deep cratonic lithosphere and generation of intraplate magmatism.Plates, Plumes, and Paradigms, 1p. abstract p. A307.ChinaAlkaline rocks, picrites
DS200712-1184
2007
Gao, S.Wu, Y-B., Gao, S., Zhang, H-F., Wang, S-H., Jiao, W-F., Liu, Y-S, Yuan, H-L.Timing of UHP metamorphism in the Hongan area, western Dabie Mountains China: evidence from zircon Pb age, trace element and Hf isotope composition.Contributions to Mineralogy and Petrology, Vol. 155, 1, pp. 123-133.ChinaUHP
DS200812-0385
2008
Gao, S.Gao, S., Rudnick, R.L., Xu, Yuan, Liu, Walker, Puchtel, Liu, Huang, Wang, WangRecycling deep cratonic lithosphere and generation of intraplate magmatism in the North Chin a Craton.Earth and Planetary Science Letters, Vol. 270, 1-2, June 15, pp. 41-53.ChinaTectonics - delamination, picrites
DS200812-0487
2008
Gao, S.Hu, Z., Gao, S.Upper crustal abundances of trace elements: a revision and update.Chemical Geology, Vol. 253, 3-4, August 15, pp. 205-221.MantleSediments - not specific to diamonds
DS200812-0678
2008
Gao, S.Liu, X., Gao, S., Diwu, C., Ling, W.Precambrian crustal growth of Yangtze Craton as revealed by detrital zircon studies.American Journal of Science, Vol. 308, 4, pp. 421-468.ChinaGeochronology
DS200812-0680
2008
Gao, S.Liu, Y., Gao, S., Gao, C., Zong, K.Recycling of lower continental crust in the Trans-North Chin a Orogen: evidence from zircon dating of mantle composite xenoliths.Goldschmidt Conference 2008, Abstract p.A563.ChinaCraton
DS200812-1162
2008
Gao, S.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
DS200812-1282
2008
Gao, S.Xu, W-L., Yang, D.B., Gao, S., Yu, Y., Pei, F.P.Mesozoic lithospheric mantle of the Central North Chin a craton: evidence from peridotite xenoliths.Goldschmidt Conference 2008, Abstract p.A1047.ChinaXenoliths
DS201012-0453
2010
Gao, S.Liu, J., Rudnick, R., Walker, R., Gao, S., Wu, F., Xu, W., Xu, Y.OS isotope evidence for diachronous formation of lithospheric mantle beneath the Trans-North Chin a oorgen, north Chin a, craton.Goldschmidt 2010 abstracts, abstractChinaGeochronology
DS201012-0828
2010
Gao, S.Wang, C., Jin, Z., Gao, S., Zhang, J., Zheng, S.Eclogite- melt/peridotite reaction: experimental constraints of the destruction mechanism of the North Chin a craton.Science China Earth Sciences, Vol. 53, 6, pp. 797-809.ChinaMelting
DS201112-0611
2011
Gao, S.Liu, J., Rudnick, R.L., Walker, R.J., Gao, S., Wu, F-y., Piccoli, P.M., Yuan, H., Xu, W-l., Xu, Yi-G.Mapping lithospheric boundaries using Os isotopes of mantle xenoliths: an example from the North Chin a Craton.Geochimica et Cosmochimica Acta, Vol. 75, 13, pp. 3881-3902.ChinaGeochronology
DS201112-1099
2011
Gao, S.Wang, H., Wu, Y-B., Gao, S., Liu, X-C., Gong, H-J., Li, Q-L., Li, X-H., Yuan, H-L.Eclogite origin and timing in the North Qinling terrane, and their bearing on the amalgamation of the South and North Chin a blocks.Journal of Metamorphic Geology, in press available,ChinaCraton
DS201112-1123
2011
Gao, S.Wu, Y., Gao, S., Liu, X., Wang, J., Peng, M., Gong, H., Yuan, H.Two stage exhumation of the ultrahigh pressure metamorphic rocks from the Western Dabie Orogen, central China.Journal of Geology, Vol. 119, pp. 15-32.ChinaUHP
DS201112-1124
2011
Gao, S.Wu, Y., Gao, S., liu, X., Wang, J., peng, M., Gong, H., Yuan, H.Two stage exhumation of ultrahigh pressure metamorphic rocks from the western Dabie orogen, Central China.Journal of Geology, Vol. 119, 1, Jan. pp. 15-31.ChinaUHP
DS201112-1125
2011
Gao, S.Wu, Y., Gao, S., Liu, X., Wang, J., Peng, M., Gong, H., Yuan, H.Two stage exhumation of ultrahigh pressure metamorphic rocks from the western Dabie Orogen, central China.Journal of Petrology, Vol. 119, no. 1, pp. 15-31.ChinaUHP
DS201112-1129
2011
Gao, S.Xu,L., Zhou, Q.J., Pei, F.P., Yang, D.B., Gao, S., Wang, W., Feng, H.Recycling lower continental crust in an intra continental setting: mineral chemistry and oxygen isotope insights from websterite xenoliths.Goldschmidt Conference 2011, abstract p.2197.ChinaNorth China craton
DS201212-0797
2013
Gao, S.Xu, W-L., Zhou, Q-J., Pei, F-P., Gao, S., Li, Q-L., Yang, Y-H.Destructive of the North Chin a craton: delamin ation or thermal/chemical erosion? Mineral chemistry and oxygen isotope insights from websterite xenoliths.Gondwana Research, Vol. 23, 1, pp. 119-129.ChinaCraton, destruction
DS201412-0960
2014
Gao, S.Wang, H., Wu, Y-B., Gao, S., Zheng, J-P., Liu, Q., Liu, X-C., Qin, Z-W., Yang, S-H., Gong, H-J.Deep subduction of continental crust in accretionary orogen: evidence from U-Pb dating on diamond-bearing zircons from the Qinling orogen, central China.Lithos, Vol. 190-191, pp. 420-429.ChinaUHP
DS201603-0419
2016
Gao, S.Shang, R., Chen, S., Wang, B-W., Wang, Z-M., Gao, S.Temperature induced irreversible phase transition from perovskite to diamond but pressure-driven back-transition in an ammonium copper formate.Angewandte Chemie, Vol. 18. 6. pp. 2137-2140.TechnologyPerovskite

Abstract: The compound [CH3 CH2 NH3 ][Cu(HCOO)3 ] undergoes a phase transition at 357 K, from a perovskite to a diamond structure, by heating. The backward transition can be driven by pressure at room temperature but not cooling under ambient or lower pressure. The rearrangement of one long copper-formate bond, the switch of bridging-chelating mode of the formate, the alternation of N-H···O H-bonds, and the flipping of ethylammonium are involved in the transition. The strong N-H···O H-bonding probably locks the metastable diamond phase. The two phases display magnetic and electric orderings of different characters.
DS201603-0432
2016
Gao, S.Yang, W., Teng, F-Z., Li, W-Y., Liu, S-A., Ke, S., Liu, Y-S., Zhang, H-F., Gao, S.Magnesium isotopic composition of the deep continental crust.American Mineralogist, Vol. 101, pp. 243-252.MantleMineralogy
DS201605-0838
2016
Gao, S.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.
DS201701-0040
2017
Gao, S.Zhang, J., Liu, Y-S., Ling, W., Gao, S.Pressure dependent compatibility of iron in garnet: insights into the proigin of ferropicrite melt mantle, China.Geochimica et Cosmochimica Acta, Vol. 197, pp. 356-377.ChinaPicrite

Abstract: Iron-rich silicate melts in the Earth’s deep mantle have been seismologically and geochemically inferred in recent years. The origin of local enrichments in iron and low-velocity seismic anomalies that have been detected in dense mantle domains are critical to understanding the mantle’s evolution, which has been canonically explained by long-term chemical reactions between the Earth’s silicate mantle and its liquid iron outer core. However, the Pleistocene alkaline ferropicrites (~0.73 Ma) from Wudi, North China, show chemical and Sr-Nd-Os isotopic features that suggest derivation from the preferential melting of silica-deficient eclogite, a lithology of delaminated mafic lower continental crust that had stagnated at mid-upper mantle depths during the Mesozoic decratonization of the North China block. These rocks are characterized by substantial enrichment in iron (14.9-15.2 wt% Fe2O3), relative depletion in silica (40-41 wt% SiO2) and decoupled Y and heavy rare earth element (HREE) compositions. These ferropicrites have particularly higher Y/Yb ratios than the other Cenozoic basalts from North China. The pressure-dependent compatibility of Fe, Y and Yb in eclogitic garnet can adequately explain the Fe-enrichment and Y-HREE decoupling of the Wudi ferropicrites and indicates that the eclogites were melted at pressures of 5-8 GPa, as also constrained by previous high-P-T experiments. This melting depth ties together a seismically imaged high-velocity anomaly that extends from 150 km to 350 km in depth under the study area, which has been commonly interpreted as evidence for the stagnation of the missing, delaminated continental lithosphere. Our findings provide an alternative mechanism to produce an extremely iron-rich mantle reservoir in addition to core-mantle interaction. Iron-rich silicate melts that form by this process are likely to be denser than the ambient mantle peridotite (and therefore drive flow downward) and may play a more significant role in the deep-mantle geophysical and geochemical diversities than previously considered.
DS201703-0406
2017
Gao, S.He, D., Liu, Y., Gao, C., Chen, C., Hu, Z., Gao, S.SiC dominated ultra-reduced mineral assemblage in carbonatitic xenoliths from the Dalihu basalt, Inner Mongolia, China.American Mineralogist, Vol. 102, pp. 312-320.China, MongoliaCarbonatite

Abstract: SiC and associated ultra-reduced minerals were reported in various geological settings, however, their genesis and preservation mechanism are poorly understood. Here, we reported a SiC-dominated ultra-reduced mineral assemblage, including SiC, TiC, native metals (Si, Fe, and Ni) and iron silicide, from carbonatitic xenoliths in Dalihu, Inner Mongolia. All minerals were identified in situ in polished/thin sections. SiC is 20-50 µm in size, blue to colorless in color, and usually identified in the micro-cavities within the carbonatitic xenolith. Four types of SiC polytypes were identified, which are dominated by ß-SiC (3C polytype) and 4H polytype followed by 15R and 6H. These SiC are featured by 13C-depleted isotopic compositions (d13C = -13.2 to -22.8‰, average = -17.7‰) with obvious spatial variation. We provided a numerical modeling method to prove that the C isotopic composition of the Dalihu SiC can be well-yielded by degassing. Our modeling results showed that degassing reaction between graphite and silicate can readily produce the low d13C value of SiC, and the spatial variations in C isotopic composition could have been formed in the progressive growth process of SiC. The detailed in situ occurring information is beneficial for our understanding of the preservation mechanism of the Dalihu ultra-reduced phase. The predominant occurrence of SiC in micro-cavities implies that exsolution and filling of CO2 and/or CO in the micro-cavities during the diapir rising process of carbonatitic melt could have buffered the reducing environment and separated SiC from the surrounding oxidizing phases. The fast cooling of host rock, which would leave insufficient time for the complete elimination of SiC, could have also contributed to the preservation of SiC.
DS2000-0895
2000
Gao, S.S.Silver, P.G., Gao, S.S.Mantle deformation beneath southern Africa #1Geological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-163.South AfricaCraton - evolution Kaapvaal, Zimbabwean, Geophysics - seismics
DS2002-0499
2002
Gao, S.S.Gao, S.S., Liu, K.H., Chen, C., Hubbard, M., Zachary, J., Zhang, Y.Old rifts never die: crustal thickening across the Midcontinent rift and its possible role in post rifting tectonics.Geological Society of America Annual Meeting Oct. 27-30, Abstract p. 79.AppalachiaTectonics - rifts
DS2002-0500
2002
Gao, S.S.Gao, S.S., Silver, P.G., Liu, K.H.Mantle discontinuities beneath southern AfricaGeophysical Research Letters, Vol. 29,10,May15,pp.129-South Africa, BotswanaGeophysics - seismics
DS2002-0958
2002
Gao, S.S.Liu, K.H., Gao, S.S.Possible seismic discontinuities in the lower mantleGeological Society of America Annual Meeting Oct. 27-30, Abstract p. 21.MantleGeophysics - seismics
DS2003-0439
2003
Gao, S.S.Gao, S.S., Liu, K.H., Davis, P.M., Slack, P.D., Zorin, Y.A., Mordvinova, V.V.Evidence for small scale mantle convection in the upper mantle beneath the Baikal RiftJournal of Geophysical Research, Vol. 108, B4, April 11, 10.1029/2002JB002039RussiaGeophysics - seismics
DS2003-0832
2003
Gao, S.S.Liu, K.H., Gao, S.S., Silver, P.G., Zhang, Y.Mantle layering across central South AmericaJournal of Geophysical Research, Vol. 108, B11, 2510 DOI. 1029/2002JB002208Brazil, South AmericaGeophysics - seismics, discontinuity, depth, Nazca, sub
DS200412-0606
2003
Gao, S.S.Gao, S.S., Liu, K.H., Davis, P.M., Slack, P.D., Zorin, Y.A., Mordvinova, V.V., Kozhevnikov, V.M.Evidence for small scale mantle convection in the upper mantle beneath the Baikal Rift zone.Journal of Geophysical Research, Vol. 108, B4, April 11, 10.1029/2002 JB002039RussiaGeophysics - seismics
DS200412-1159
2003
Gao, S.S.Liu, K.H.,Gao, S.S., Silver, P.G., Zhang, Y.Mantle layering across central South America.Journal of Geophysical Research, Vol. 108, B11, ESE 9 10.1029/2003 JB002208South America, MantleGeophysics - seismics
DS200412-1824
2004
Gao, S.S.Silver, P.G., Fouch, M.J., Gao, S.S., Schmitz, M.Seismic anisotropy, mantle fabric, and the magmatic evolution of Precambrian southern Africa.South African Journal of Geology, Vol. 107, 1/2, pp. 45-58.Africa, South AfricaGeophysics - seismics, tectonics, magmatism
DS200612-0964
2006
Gao, S.S.Nair, S.K., Gao, S.S., Liu, K.H., Silver, P.G.Southern African crustal evolution and composition: constraints from receiver function system.Journal Geophysical Research, Vol. 111, B2, Feb. 17, B02304Africa, South AfricaGeophysics - seismics
DS200712-0638
2006
Gao, S.S.Liu, K.H., Gao, S.S.Mantle transition zone discontinuities beneath the Baikal rift and adjacent areas.Journal of Geophysical Research, Vol. 111, B 11, B11301.RussiaGeophysics - seismics
DS201112-0001
2011
Gao, S.S.Abdelsalam, M.G., Gao, S.S., Liegeois, J-P.Upper mantle structure of the Sahara metacraton.Journal of African Earth Sciences, Vol. 60, 5, pp. 328-336.AfricaUpper mantle structure, convection
DS201312-0292
2014
Gao, S.S.Gao, S.S., Liu, K.H.Imaging mantle discontinuities using multiply-reflected P to S conversions.Earth and Planetary Science Letters, Vol. 402, pp. 99-106.MantleGeophysics - seismics
DS201312-0293
2013
Gao, S.S.Gao, 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
DS201312-0738
2014
Gao, S.S.Refayee, H.A., Yang, B.B., Liu, K.H., Gao, S.S.Mantle flow and lithosphere asthenosphere coupling beneath the southwestern edge of the North American craton: constraints from shear wave splitting measurements.Earth and Planetary Science Letters, Vol. 402, pp. 209-220.CanadaAnisotropy
DS201512-1997
2015
Gao, S.S.Yu, Y., Liu, K.H., Reed, C.A., Moidaki, M., Mickus, K., Atekwana, E.A., Gao, S.S.A joint receiver function and gravity study of crustal structure beneath the incipient Okavango Rift, Botswana.Geophysical Research Letters, Vol. 42, 20, pp. 8398-8405.Africa, BotswanaGeophysics - gravity

Abstract: Rifting incorporates the fundamental processes concerning the breakup of continental lithosphere and plays a significant role in the formation and evolution of sedimentary basins. In order to decipher the characteristics of rifting at its earliest stage, we conduct the first teleseismic crustal study of one of the world's youngest continental rifts, the Okavango Rift Zone (ORZ), where the magma has not yet breached the surface. Results from receiver function stacking and gravity modeling indicate that the crust/mantle boundary beneath the ORZ is uplifted by 4-5 km, and the initiation of the ORZ is closely related to lithospheric stretching. Possible decompression melting of the subcrustal lithosphere occurs beneath the ORZ, as evidenced by a relatively low upper mantle density based on the gravity modeling.
DS201909-2106
2019
Gao, S.S.Wang, T., Gao, S.S., Dai, Y., Yang, Q., Liu, K.H.Lithospheric structure and evolution of southern Africa: constraints from joint inversion of Rayleigh wave dispersion and receiver functions.Geochemistry, Geophysics, Geosystems, Vol. 20, 7, pp. 3311-3327.Africa, South Africageophysics

Abstract: We conduct a joint inversion of teleseismic receiver functions and Rayleigh wave phase velocity dispersion from both ambient noise and earthquakes using data from 79 seismic stations in southern Africa, which is home to some of the world's oldest cratons and orogenic belts. The area has experienced two of the largest igneous activities in the world (the Okavango dyke swarm and Bushveld mafic intrusion) and thus is an ideal locale for investigating continental formation and evolution. The resulting 3-D shear wave velocities for the depth range of 0-100 km and crustal thickness measurements show a clear spatial correspondence with known geological features observed on the surface. Higher than normal mantle velocities found beneath the southern part of the Kaapvaal craton are consistent with the basalt removal model for the formation of cratonic lithosphere. In contrast, the Bushveld complex situated within the northern part of the craton is characterized by a thicker crust and higher crustal Vp/Vs but lower mantle velocities, which are indicative of crustal underplating of mafic materials and lithospheric refertilization by the world's largest layered mafic igneous intrusion. The thickened crust and relatively low elevation observed in the Limpopo belt, which is a late Archean collisional zone between the Kaapvaal and Zimbabwe cratons, can be explained by eclogitization of the basaltic lower crust. The study also finds evidence for the presence of a stalled segment of oceanic lithosphere beneath the southern margin of the Proterozoic Namaqua-Natal mobile belt.
DS200412-2155
2004
Gao, T.Xie, Z., Zheng, Y-F., Jahn, B-M., Ballevre, M., Chen, J., Gautier, P., Gao, T., Gong, B., Zhou, J.Sm Nd and Rb Sr dating of pyroxene garnetite from North Dabie in east centra China: problem of isotope disequilibrium due to retChemical Geology, Vol. 206, 1-2, May 28, pp. 137-158.ChinaUHP, eclogite, geochronology
DS201112-1171
2011
Gao, T.Zheng, Y-F., Gao, X-Y., Chen, R-X., Gao, T.Zr in rutile thermometry of eclogite in the Dabie orogen: constraints on rutile growth during continental subduction zone metamorphism.Journal of Asian Earth Sciences, Vol. 40, 2, Jan. pp. 427-451.ChinaSubduction
DS200612-1602
2006
Gao, T.S.Zhao, Z-F., Zheng, Y-F., Gao, T.S., Wu, Y.B., Chen, B., Chen, F-K., Wu, F.Y.Isotopic constraints on age and duration of fluid assisted high pressure eclogite facies recrystallization during exhumation of deeply subducted continental crursJournal of Metamorphic Geology, Vol. 24, 8, pp. 687-702.ChinaUHP Sulu orogen
DS200412-0607
2004
Gao, W.Gao, W., Grand, S.P., Baldridge, W.S., Wilson, D., West, M., Ni, J.F., Aster, R.Upper mantle convection beneath the central Rio Grande rift imaged by P and S wave tomography.Journal of Geophysical Research, Vol. 109, 3, DOI 10.1029/2003 JB002743United States, New Mexico, Colorado PlateauGeophysics - seismics, tectonics
DS200412-2101
2004
Gao, W.West, M., Ni, J., Baldridge, W.S., Wilson, D., Aster, R., Gao, W., Grand, S.Crust and upper mantle shear wave structure of the southwest United States: implications for rifting and support for high elevatJournal of Geophysical Research, Vol. 109, 3, DOI 10.1029/2003 JB002575United States, California, Colorado PlateauGeophysics - seismics, tectonics
DS200512-1185
2005
Gao, W.Wilson, D., Aster, R., Ni, J., Grand, S., West, M., Gao, W.,Baldridge, W.S., Semken, S.Imaging the seismic structure of the crust and upper mantle beneath the Great Plains, Rio Grande Rift, and Colorado Plateau using receiver functions.Journal of Geophysical Research, Vol. 110, B5, 10.1029/2004 JB003492United States, Colorado PlateauGeophysics - seismics
DS200512-1186
2005
Gao, W.Wilson, D., Aster, R., Ni, J., Grand, S., West, M., Gao, W., Baldridge, W.S., Semken, S.Imaging the seismic structure of the crust and upper mantle beneath the Great Plains, Rio Grande Rift and Colorado Plateau using receiver functions.Journal of Geophysical Research, Vol. 110, B5 May 28, B05306 10.1029/2004 JB003492United States, ColoradoGeophysics - seismics
DS200812-1072
2008
Gao, W.Sine, C.R., Wilson, D., Gao, W., Grand, S.P., Aster, R., Ni, J., Baldridge, W.S.Mantle structure beneath the western edge of the Colorado Plateau.Geophysical Research Letters, Vol. 35, 10, May 28, L10303.United States, Colorado PlateauTectonics
DS200512-0665
2004
Gao, X.Ma, Z., Gao, X.Some thoughts on the research on continental tectonics, oceanic tectonics and earth tectonics.Earth Science Frontiers, Vol. 11, 4, pp. 9-14. Ingenta 1045384804ChinaTectonics
DS201112-0344
2011
Gao, X.Y.Gao, X.Y., Zheng, Y.F., Chen, Y.X.Dehydration melting of ultrahigh pressure eclogite in the Dabie Orogen: evidence from multiphase solid inclusions in garnet.Journal of Metamorphic Geology, in press availableChinaUHP
DS201212-0228
2012
Gao, X.Y.Gao, X.Y., Zheng, Y.F., Chen, Y.X.Dehydration melting of ultra high pressure eclogite in the Dabie Orogen: evidence from multiphase solid inclusions in garnet.Journal of Metamorphic Geology, Vol. 30, 2, pp. 193-210.ChinaUHP
DS201112-0345
2011
Gao, X-Y.Gao, X-Y., Zheng, Y-F., Chen, Y-X.U Pb ages and trace elements in metamorphic zircon and titanate from UHP eclogite in the Dabie Orogen: constraints on P-T-t path.Journal of Metamorphic Geology, in press availableChinageochronology
DS201112-0346
2011
Gao, X-Y.Gao, X-Y., Zheng, Y-F., Chen, Y-X.U-Pb ages and trace elements in metamorphic zircon and titanite from UHP eclogite in the Dabie orogen: constraints on P-T-t path.Journal of Metamorphic Geology, Vol. 29, 7, pp. 721-740.ChinaUHP
DS201112-1171
2011
Gao, X-Y.Zheng, Y-F., Gao, X-Y., Chen, R-X., Gao, T.Zr in rutile thermometry of eclogite in the Dabie orogen: constraints on rutile growth during continental subduction zone metamorphism.Journal of Asian Earth Sciences, Vol. 40, 2, Jan. pp. 427-451.ChinaSubduction
DS201312-0294
2013
Gao, X-Y.Gao, X-Y., Zheng, Y.F., Chen, Y.X., Hu, Z.Trace element composition of continentally subducted slab-derived melt: insight from multiphase solid inclusions in ultrahigh pressure eclogite in the Dabie Orogen.Journal of Metamorphic Geology, Vol. 31, 4, pp. 453-468.ChinaUHP
DS201412-0122
2014
Gao, X-Y.Chen, Y-X., Zheng, Y-F., Gao, X-Y., Hu, Z.Multiphase solid inclusions in zoisite bearing eclogite: evidence for partial melting of ultrahigh pressure metamorphic rocks during continental collision.Lithos, Vol. 200-201, pp. 1-21.ChinaSulu UHP
DS201412-0123
2014
Gao, X-Y.Chen, Y-X., Zheng, Y-F., Gao, X-Y., Hu, Z.Multiphase solid inclusions in zoisite bearing eclogite: evidence for partial melting of ultrahigh-pressure metamorphic rocks during continental collision.Lithos, Vol. 200-201, pp. 1-21.MantleEclogite
DS201412-0266
2014
Gao, X-Y.Gao, X-Y., Zheng, Y-F., Chen, Y-X., Hu, Z.Composite carbonate and silicate multiphase solid inclusions in metamorphic garnet from ultrahigh-P eclogite in the Dabie orogen.Journal of Metamorphic Geology, Vol. 32, 9, pp. 961-980.ChinaSubduction
DS201708-1644
2017
Gao, X-Y.Gao, X-Y.Multiphase solid inclusions in UHP eclogite from the Dabie orogen: constraints on anatectic melts during continental collision.11th. International Kimberlite Conference, PosterChinaUHP
DS201012-0594
2010
Gao, Y.Posukhova, T.V., Dorofeev, S.A., Gao, Y.Mineralogy of the wastes from diamond bearing mines. Arkangelsk LiaoninInternational Mineralogical Association meeting August Budapest, abstract p. 349.Russia, ChinaMining - recycling
DS201312-0180
2013
Gao, Y.Crampin, S., Gao, Y.The new geophysics.Terra Nova, Vol. 25, 3, pp. 173-180.MantleFluid-rock deformation
DS201412-0644
2013
Gao, Y.Obayashi, M., Yoshimitsu, J., Noelt, G., Fukao, Y., Shiobara, H., Sugioka, H., Miyamachi, H., Gao, Y.Finite frequency whole mantle P wave tomography: improvement of subducted slab images.Geophysical Research Letters, Vol. 40, 21, pp. 5652-5657.MantleTomography
DS201911-2523
2019
Gao, Y.Gao, Y., Yin, P.Determination of crystallite size of nanodiamond by raman spectroscopy.Diamond & Related Materials, Vol. 99, 107524Globalnanodiamond

Abstract: Although the phonon confinement model (PCM) was claimed to be successfully used to accurately calculate the size of larger Si nanocrystals, quantitative size characterization by Raman spectra still remains a challenge in the case of nanodiamonds due to its complexity. Here, we find that a local-mode model of Raman spectra developed recently can be employed to determine the bond number of the ordered diamond core in nanodiamonds, and then furtherly determine the size of nanodiamonds. The Raman lines of nanodiamonds of 3.0?nm, 2.0?nm, 2.2?nm, 3.3?nm, 3.7?nm 4.42?nm and 6.3?nm are calculated. Results are in good agreement with the measured Raman spectra. It not only provides a new approach to predict the size of nanodiamonds accurately by Raman spectra, but also helps to clarify issues in Raman spectra of nanodiamond and other carbon nanomaterials.
DS201609-1747
2016
Gao, Y-J.Su, B., Chen, Y., Guo, S., Chu, Z-Y., Liu, J-B., Gao, Y-J.Carbonatitic metasomatism in orogenic dunites from Lijiatun in the Sulu UHP terrane, eastern China.Lithos, Vol. 262, pp. 266-284.ChinaCarbonatite

Abstract: Among orogenic peridotites, dunites suffer the weakest crustal metasomatism at the slab-mantle interface and are the best lithology to trace the origins of orogenic peridotites and their initial geodynamic processes. Petrological and geochemical investigations of the Lijiatun dunites from the Sulu ultrahigh-pressure (UHP) terrane indicate a complex petrogenetic history involving melt extraction and multistage metasomatism (carbonatitic melt and slab-derived fluid). The Lijiatun dunites consist mainly of olivine (Fo = 92.0-92.6, Ca = 42-115 ppm), porphyroblastic orthopyroxene (En = 91.8-92.8), Cr-spinel (Cr# = 50.4-73.0, TiO2 < 0.2 wt.%) and serpentine. They are characterized by refractory bulk-rock compositions with high MgO (45.31-47.07 wt.%) and Mg# (91.5-91.9), and low Al2O3 (0.48-0.70 wt.%), CaO (0.25-0.44 wt.%) and TiO2 (< 0.03 wt.%) contents. Whole-rock platinum group elements (PGE) are similar to those of cratonic mantle peridotites and Re-Os isotopic data suggest that dunites formed in the early Proterozoic (~ 2.2 Ga). These data indicate that the Lijiatun dunites were the residues of ~ 30% partial melting and were derived from the subcontinental lithospheric mantle (SCLM) beneath the North China craton (NCC). Subsequent carbonatitic metasomatism is characterized by the formation of olivine-rich (Fo = 91.6-92.6, Ca = 233-311 ppm), clinopyroxene-bearing (Mg# = 95.9-96.7, Ti/Eu = 104-838) veins cutting orthopyroxene porphyroblasts. Based on the occurrence of dolomite, mass-balance calculation and thermodynamic modeling, carbonatitic metasomatism had occurred within the shallow SCLM (low-P and high-T conditions) before dunites were incorporated into the continental subduction channel. These dunites then suffered weak metasomatism by slab-derived fluids, forming pargasitic amphibole after pyroxene. This work indicates that modification of the SCLM beneath the eastern margin of the NCC had already taken place before the Triassic continental subduction. Orogenic peridotites derived from such a lithospheric mantle wedge may be heterogeneously modified prior to their incorporation into the subduction channel, which would set up a barrier for investigation of the mass transfer from the subducted crust to the mantle wedge through orogenic peridotites.
DS201610-1912
2016
Gao, Y-J.Su, B., Chen, Y., Guo, S., Chu, Z-Y., Liu, J-B., Gao, Y-J.Carbonatitic metasomatism in orogenic dunites from Lijiatun in the Sulu UHP terrane, eastern China.Lithos, Vol. 262, pp. 266-284.ChinaUHP, carbonatite

Abstract: Among orogenic peridotites, dunites suffer the weakest crustal metasomatism at the slab-mantle interface and are the best lithology to trace the origins of orogenic peridotites and their initial geodynamic processes. Petrological and geochemical investigations of the Lijiatun dunites from the Sulu ultrahigh-pressure (UHP) terrane indicate a complex petrogenetic history involving melt extraction and multistage metasomatism (carbonatitic melt and slab-derived fluid). The Lijiatun dunites consist mainly of olivine (Fo = 92.0-92.6, Ca = 42-115 ppm), porphyroblastic orthopyroxene (En = 91.8-92.8), Cr-spinel (Cr# = 50.4-73.0, TiO2 < 0.2 wt.%) and serpentine. They are characterized by refractory bulk-rock compositions with high MgO (45.31-47.07 wt.%) and Mg# (91.5-91.9), and low Al2O3 (0.48-0.70 wt.%), CaO (0.25-0.44 wt.%) and TiO2 (< 0.03 wt.%) contents. Whole-rock platinum group elements (PGE) are similar to those of cratonic mantle peridotites and Re-Os isotopic data suggest that dunites formed in the early Proterozoic (~ 2.2 Ga). These data indicate that the Lijiatun dunites were the residues of ~ 30% partial melting and were derived from the subcontinental lithospheric mantle (SCLM) beneath the North China craton (NCC). Subsequent carbonatitic metasomatism is characterized by the formation of olivine-rich (Fo = 91.6-92.6, Ca = 233-311 ppm), clinopyroxene-bearing (Mg# = 95.9-96.7, Ti/Eu = 104-838) veins cutting orthopyroxene porphyroblasts. Based on the occurrence of dolomite, mass-balance calculation and thermodynamic modeling, carbonatitic metasomatism had occurred within the shallow SCLM (low-P and high-T conditions) before dunites were incorporated into the continental subduction channel. These dunites then suffered weak metasomatism by slab-derived fluids, forming pargasitic amphibole after pyroxene. This work indicates that modification of the SCLM beneath the eastern margin of the NCC had already taken place before the Triassic continental subduction. Orogenic peridotites derived from such a lithospheric mantle wedge may be heterogeneously modified prior to their incorporation into the subduction channel, which would set up a barrier for investigation of the mas
DS1999-0220
1999
Gao Mai, et al.Flint, D.J., Gao Mai, et al.Mineral and petroleum exploration and development in Western Australia in1997-8. Brief mention of diamondsAustralian Institute of Mining and Metallurgy (AusIMM) Bulletin., No. 1, Feb. pp. 22-25.Australia, Western AustraliaNews item, Diamonds mentioned p. 25.
DS1990-0512
1990
Gao ShanGao Shan, Zhang Benren, Li ZejiuGeochemical evidence for Proterozoic continental arc and continental margin rift magmatism along the northern margin of the Yangtze craton, South ChinaPrecam. Res, Vol. 47, pp. 205-221ChinaCraton -Yangtze, Tectonics -rift
DS1990-0940
1990
Gao ShanjiLiu Guangliang, Lian Dawei, Gao Shanji, Wang XiongwuMineralogy of Dahongshan lamproite in Hubei provinceInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 832-833ChinaLamproite, Dahongshan
DS1990-1635
1990
Gao YanZhou Xiuzhong, Huang Yunhaui, Qin Shuying, Deng Chujun, Gao Yan, YangStudies on the type and the typomorphic characteristics of the garnets From kimberlites and the relationship between the garnets and diamondInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 141-142ChinaMineralogy -garnets, Diamond morphology
DS1991-1932
1991
Gao YanZhou Xiouzhong, Huang Yunhui, Qin Shuying, Gao Yan, Yang JianminTypes, typomorphic characteristics of garnet from kimberlites in Shandong and Liaoning and its relationship with diamond.*CHIYanshi Kuangwuxue Zazhi (Acta Petrologica et Mineralogica)*CHI, Vol. 10, No. 3, August pp. 252-264ChinaPetrology, Garnets from kimberlites
DS1995-0578
1995
Gao YanGao Yan, Li Jingzhi, Zhang BeiliThe infrared microscope and rapid identification of gemstonesJournal of Gemology, Vol. 24, No. 6, April, pp. 411-414.GlobalMicroscopy
DS2001-1077
2001
Gao.S.S.Silver, P.G., Gao.S.S., Lio, K.H.Mantle deformation beneath southern Africa #2Geophysical Research Letters, Vol. 28, No. 13, July 1, pp. 2493-6.South AfricaGeophysics - seismics, Craton - evolution Kaapvaal, Zimbabwean, Kaapvaal Craton
DS1994-0571
1994
Gaolathe, B.Gaolathe, B.Lessons from Botswana mining experienceRaw Materials Report, Vol. 9, No. 3, pp. 2-14.BotswanaMining, Development, legal, laws
DS1989-0468
1989
Gaonach, H.Gaonach, H., Picard, C., Ludden, J.N., Francis, D.M.Alkaline rocks from a Proterozoic volcanic island in the Cape Smith thrustbelt, New Quebec.Geoscience Canada, Vol. 16, No. 3, September pp. 137-139QuebecBasanite, Nephelinite, phonolites, Proterozoic
DS1992-0512
1992
Gaonach, H.Gaonach, H., Ludden, Picard, FrancisHighly alkaline lavas in a Proterozoic rift zone: implications for Precambrian mantle metasomatic processGeology, Vol. 20, Mar. pp. 247-50.Labrador, Ungava, QuebecTectonics, Cape Smith thrust belt, Mantle metasomatism, Alkaline lavas, Nephelinites, basanites
DS1989-0469
1989
Gaonac'h, H.Gaonac'h, H., Picard, C., Ludden, J.N., Francis, D.M.Alkaline rocks from a Proterozoic volcanic island In the Cape Smith thrust belt, New QuebecGeoscience Canada, Vol. 16, No. 3, pp. 137-9.Quebec, Ungava, LabradorAlkaline rocks
DS201511-1877
2015
Gaonkar, M.Sastry, M.D., Mane, S., Gaonkar, M., Bhide, M.K., Desai, S.N., Ramachandran, K.T.Luminescence studies of gemstones and diamonds.International Journal of Luminescence and Applications, Vol. 5, 3, pp. 293-297.TechnologyLuminescence

Abstract: Some of the minerals like Corundum, chryso beryl, beryllium alumino silicate (emerald) and also Diamond exhibit exceptional optical properties[1] and in some cases attractive colours; in India these were recognized quite early since the days of Indus valley civilization. In more recent times there has been a lot of scientific interest in colours and colour modifications in Gem minerals and in Diamonds. Science of gem stones deals with their identification by non destructive means and understanding of origin of colour and excellent optical properties[1]. Optical methods have long been used to obtain properties like ‘Refractive Index’ which still remains an important parameter as a preliminary test to identify the gemstone/mineral. The spectroscopic studies of gem grade minerals are essentially directed towards some of these features in identifying and understanding the spectral properties of chromophores, either chemical impurities and/or radiation induced point defects, in solids. In this context a variety of spectroscopic methods are used to address the problems of the Gem stone identification and identification of origin of colours and colour modification treatments. The methods frequently used in Gem testing labs are the following: (i)Electronic absorption in UV-Visible-NIR range.(ii)UV-Vis excited luminescence, (iii) Vibrational spectra – Absorption in the Infra red range (iv) Vibrational spectra using Light Scattering (Raman spectroscopy) (v)Surface Fluorescence mapping Under deep UV excitation. The present paper deals with the luminescence studies in rubies, sapphires, emeralds and diamonds. Special mention may be made of fluorescence mapping using deep UV excitation (around 205 nm) corresponding to the band gap of diamond. Under such an excitation inter band excitation takes place creating a e-h pair and most of the absorption and subsequent emission being restricted to the surface. This makes surface mapping possible and thereby elucidating the growth patterns. This is invaluable in the diagnostics for the detection of synthetic diamonds. In this introductory presentation on the Luminescence methods in Gemmology, we give a brief account of optical spectroscopic methods which mainly deal with identification of corundum based gem stones (rubies, sapphire) and diamonds including the electronic absorption and luminescence of chromophore centres. In gem testing infrared absorption and Raman scattering methods are main work horses and they will be brought in as and when necessary to give a complete picture.
DS1989-0470
1989
Gapais, D.Gapais, D.Shear structures within deformed granites: mechanical and thermalindicatorsGeology, Vol. 17, No. 12, December pp. 1144-1147GlobalStructure -shears, Granites
DS1995-1598
1995
Gapais, D.Roman Berdiel, T., Gapais, D., Brun, J.P.Analogue models of laccolith formationJournal of Structural Geology, Vol. 17, No. 9, pp. 1337-1346GlobalMagma -intrusions, Laccoliths
DS1995-1599
1995
Gapais, D.Roman-Berdiel, T., Gapais, D., Brun, J.P.Analogue models of laccolith formationJournal of Structural Geology, Vol. 17, No. 9, pp. 1337-1346.GlobalLaccolith, Model - not specific to kimberlites
DS1996-0351
1996
Gapais, D.De Urreiztieta, M., Gapais, D., Rossello, E.Cenozoic dextral transpression and basin development at the southern edge of the Puna PlateauTectonophysics, Vol. 254, No. 1-2, March 30, pp. 17-40ArgentinaTectonics, Puna Plateau
DS200512-0314
2005
Gapais, D.Gapais, D., Brun, J-P., Cobbold, P.R.Deformation mechanisms, rheology and tectonics: from minerals to the lithosphere.Geological Society of London, SP 243, 320p.MantleBook - review papers on rheology, UHP
DS200612-0204
2006
Gapais, D.Cagnard, F., Durrieu, N., Gapais, D., Brun, J-P, Ehlers, C.Crustal thickening and lateral flow during compression of hot lithospheres, with particular reference to Precambrian times.Terra Nova, Vol. 18, Feb. pp. 72-78.MantleGeothermometry
DS200612-0205
2006
Gapais, D.Cagnard, F., Durrieu, N., Gapais, D., Brun, J-P., Ehlers, C.Crustal thickening and lateral flow during compression of hot lithospheres, with particular reference to Precambrian times.Terra Nova, Vol. 18, 1, Feb. pp. 72-78.MantleGeophysics - seismics
DS200612-0206
2006
Gapais, D.Cagnard, F., Durrieu, N., Gapais, D., Brun, J-P., Ehlers, C.Crustal thickening and lateral flow during compression of hot lithospheres, with particular reference to Precambrian times.Terra Nova, Vol. 18, 1, pp. 72-78.MantleMelting
DS200812-0917
2007
Gapais, D.Precigout, J., Gueydan, F., Gapais, D., Garrido, C.J., Eassaifi, A.Strain localization in the subcontinental mantle ?? a ductile alternative to the brittle mantle.Tectonophysics, Vol. 445, 3-4, pp. 318-336.MantleSubduction
DS200912-0242
2009
Gapais, D.Gapais, D., Cagnard, F., Guyedan, F., Barbey, P., Bellevre, M.Mountain building and exhumation process through time: inference from nature and models.Terra Nova, Vol. 21, 3, pp. 188-194.MantleTectonics - not specific to diamonds
DS2000-0330
2000
GapeevGenshaft, Y.S., Tselmovich, GapeevPicroilmenite: factors determining its compositionDoklady Academy of Sciences, Vol. 373A, No. 6, Aug-Sept. pp.969-73.GlobalMineralogy - picroilmenite
DS1950-0388
1958
Gapeeva, G.M.Gapeeva, G.M.The Position of the Kimberlites in the Genetic Classification of Igneus Rocks.Niiga Info. Bulletin., No. 1, PP. 137-140.RussiaBlank
DS1991-0339
1991
Gapsar, J.C.Danni, J.C.M., Gapsar, J.C., Gonzaga, G.M.The Fazenda Alagoinha intrusion, Tres Ranchos, GoaisFifth International Kimberlite Conferences Field Excursion Guidebook, Servico Geologico do Brasil (CPRM) Special, pp. 31-36BrazilGeology, Kimberlitic intrusions
DS200412-0608
2004
Garagash, I.A.Garagash, I.A., Ermakov, V.A.A probable geodynamic model of the Early Earth.Doklady Earth Sciences, Vol. 394, 1, pp. 73-77.GlobalTectonomagmatic, geochronology
DS200712-0348
2006
Garai, J.Garai, J., Haggerty, S.E., Rekhi, S., Chance, M.Infrared absorption investigations confirm the extraterrestrial origin of carbonado diamonds.The Astrophysical Journal, Vol. 653, Dec. 20, pp. L153-L156.TechnologyCarbonado diamonds
DS202001-0028
2019
Garakoev. A.Moilanen, J., Pavlov, B., Karshakov, E., Volovitsky, A., Garakoev. A.Airborne geophysical technologies as a basis for diamond field prognoses in regional and state scale.2019 Twelth International Conference Oct 1-3. Moscow, IEEE DOI 11.09/MLSD .2019.8911014Africa, Angola, Russia, Yakutiageophysics

Abstract: We show how to increase the effectiveness of the prognoses of kimberlite bodies by using airborne geophysical technologies. We show the advantages of electromagnetic and magnetic methods for predicting kimberlite pipes. You will see examples of a regional diamond survey in Angola and Siberia.
DS2002-0071
2002
GaraninAshchepkov, I.V., Vladykin, N.V., Mitchell, R.H., Coopersmith, H., GaraninMantle evolution beneath the Colorado Plateau: interpretation of the study of mineralDoklady Earth Sciences, Vol. 385A, 6, July-August, pp. 721-6.ColoradoTectonics, geochemistry, Deposit - Kelsey Lake
DS201112-0639
2011
GaraninMalkovets, V.G., Griffin, Pearson, Rezvukhin, O'Reilly, Pokhilenko, Garanin, Spetsius, LitasovLate metasomatic addition of garnet to the SCLM: Os-isotope evidence.Goldschmidt Conference 2011, abstract p.1395.RussiaUdachnaya, Daldyn
DS1993-1651
1993
Garanin, D.A.Varlamov, D.A., Garanin, D.A., Kostroviski, S.I.Unusual association of ore minerals in inclusion of garnet from International kimberlite pipe. (Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 328, No. 5, Feb. pp. 596-600.Russia, YakutiaMineral inclusions, Deposit -International
DS201708-1645
2017
Garanin, K.Garanin, K.Zarya diamond deposit, Yakutian Province, Russia.11th. International Kimberlite Conference, PosterRussia, Yakutiadeposit - Zarya
DS201903-0511
2018
Garanin, K.Garanin, K.Alrosa - world top diamond producer.7th Symposio Brasleiro de geologia do diamante, 54p ppts AvailableRussiaoverview
DS2003-0125
2003
Garanin, K.V.Bobrov, A.V., Verichev, E.M., Garanin, V.K., Garanin, K.V., Kudryavtseva, G.P.Xenoliths of mantle metamorphic rocks from the Diamondiferous V. Grib pipe (8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, POSTER abstractRussia, ArkangelskDeposit - Grib
DS200412-0173
2003
Garanin, K.V.Bobrov, A.V., Verichev, E.M., Garanin, V.K., Garanin, K.V., Kudryavtseva, G.P.Xenoliths of mantle metamorphic rocks from the Diamondiferous V. Grib pipe ( Arkangelsk province): petrology and genetic aspects8 IKC Program, Session 6, POSTER abstractRussia, Kola Peninsula, ArchangelMantle petrology Deposit - Grib
DS200512-0026
2005
Garanin, K.V.Appollonov, V.N., Verzhak, V.V., Garanin, K.V., Garanin, V.K., Kudryavtseva, G.P., Shlykov, V.G.Saponite from the Lomonosov diamond deposit.Moscow University Geology Bulletin, Vol. 59, 2, pp. 69-84.Russia, Kola Peninsula, ArchangelGeology
DS200512-0315
2004
Garanin, K.V.Garanin, K.V.Alkaline ultrabasic rocks in the Arkangelsk diamond province: present state of knowledge and prospects for studies.Moscow University Geology Bulletin, Vol. 59, 1, pp. 35-45.Russia, Kola Peninsula, ArchangelAlkalic
DS200612-0345
2006
Garanin, K.V.Dorjnamjaa, D., Selenge, D., Garanin, K.V.Diamond bearing astropipes in Mongolia their recognition and characteristics.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1. abstract only.Asia, MongoliaUHP Breccia pipes
DS200712-1118
2006
Garanin, K.V.Verzhak, D.V., Garanin, K.V.Diamond deposits of Arkhangelsk Oblast and environmental problems associated with their development.Moscow University Geology Bulletin, Vol. 60, 6, pp. 20-30.Russia, Kola PeninsulaEnvironmental
DS201212-0177
2012
Garanin, K.V.Dyakonov, D.B., Garanin, VK., Garanin, K.V., Bushueva, E.B., Enalieva, M.A., Wedensky, E.S.Searching for new diamond deposits in western Liberia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, LiberiaProspects - Yambassen, Kumgbo
DS201212-0229
2012
Garanin, K.V.Garanin, V.K., Anashkin, S.M., Bovkun, A.V., Jelsma, H., Shmakov, I.I., Garanin, K.V.Groundmass microcrystalline oxides from the Marsfontein pipe ( RSA) , Catoca, Camachia and other Angolan kimberlite pipes.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, Angola, South AfricaDeposit - Marsfontein, Catoca, Camachia
DS201212-0733
2012
Garanin, K.V.Tretyachenko, W., Bovkun, A.V., Garanin, K.V., Garanin, V.K., Tretyachenko, N.G.Formation features of the early Hercynic alkaline ultrabasic and basic volcanic complexes from Zimny Bereg area, north east of Archangelsk region, Russia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, Archangel, Kola PeninsulaAlkalic
DS201412-0267
2014
Garanin, K.V.Garanin, V.K., Bovkun, A.V., Garanin, K.V., Kriulina, G.Y., Iwanich, W.Diamonds and its grade in different petrochemical types of kimberlites ( based on Russian diamond deposits).6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 4p. AbstractRussiaMineral chemisty
DS201412-0268
2014
Garanin, K.V.Garanin, V.K., Garanin, K.V., Iwanuch, W.Polygenesis and discreteness of diamond formation. 6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 1p. AbstractGlobalDiamond genesis
DS201412-0269
2014
Garanin, K.V.Garanin, V.K., Garanin, K.V., Iwanuch, W.Diamonds from Russia. History6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 5p. AbstractRussiaHistory and discoveries
DS201412-0270
2014
Garanin, K.V.Garanin, V.K., Garanin, K.V., Kriulina, G.Y.Granitoids of different geochemical types of Baikal area: their diamonds from Russia.30th. International Conference on Ore Potential of alkaline, kimberlite and carbonatite magmatism. Sept. 29-, http://alkaline2014.comRussiaDiamonds
DS201802-0236
2017
Garanin, K.V.Garanin, K.V.Polygenesis and discrete character - fundamental basis for the natural diamond genesis. *** IN RUSStarosin, V.I. (ed) Problems of the mineralogy, economic geology and mineral resources. MAKS Press, Moscow *** IN RUS, pp. 88-127.Technologydiamond morphology
DS201802-0237
2017
Garanin, K.V.Garanin, K.V., Serov, I.V., Nikiforova, A.Yu., Grakhanov, O.S.The ALROSA geological prospecting complex and the analysis of the base for the diamond mining in Russian Federation to 2030. *** IN RUSStarosin, V.I. (ed) Problems of the mineralogy, economic geology and mineral resources. MAKS Press, Moscow *** IN RUS, pp. 22-40.Russiatechnology
DS201808-1722
2018
Garanin, K.V.Agashev, A.M., Nakai, S., Serov, I.V., Tolstov, A.V., Garanin, K.V., Kovalchuk, O.E.Geochemistry and origin of the Mirny field kimberlites, Siberia.Mineralogy and Petrology, doi.org/10.1007/s00710-018-06174 12p.Russia, Siberiadeposit - Mirny

Abstract: Here we present new data from a systematic Sr, Nd, O, C isotope and geochemical study of kimberlites of Devonian age Mirny field that are located in the southernmost part of the Siberian diamondiferous province. Major and trace element compositions of the Mirny field kimberlites show a significant compositional variability both between pipes and within one diatreme. They are enriched in incompatible trace elements with La/Yb ratios in the range of (65-00). Initial Nd isotope ratios calculated back to the time of the Mirny field kimberlite emplacement (t?=?360 ma) are depleted relative to the chondritic uniform reservoir (CHUR) model being 4 up to 6 ?Nd(t) units, suggesting an asthenospheric source for incompatible elements in kimberlites. Initial Sr isotope ratios are significantly variable, being in the range 0.70387-0.70845, indicating a complex source history and a strong influence of post-magmatic alteration. Four samples have almost identical initial Nd and Sr isotope compositions that are similar to the prevalent mantle (PREMA) reservoir. We propose that the source of the proto-kimberlite melt of the Mirny field kimberlites is the same as that for the majority of ocean island basalts (OIB). The source of the Mirny field kimberlites must possess three main features: It should be enriched with incompatible elements, be depleted in the major elements (Si, Al, Fe and Ti) and heavy rare earth elements (REE) and it should retain the asthenospheric Nd isotope composition. A two-stage model of kimberlite melt formation can fulfil those requirements. The intrusion of small bodies of this proto-kimberlite melt into lithospheric mantle forms a veined heterogeneously enriched source through fractional crystallization and metasomatism of adjacent peridotites. Re-melting of this source shortly after it was metasomatically enriched produced the kimberlite melt. The chemistry, mineralogy and diamond grade of each particular kimberlite are strongly dependent on the character of the heterogeneous source part from which they melted and ascended.
DS201312-0018
2013
Garanin, V.Anashkin, S., Bovkun, A.,Bindi, L., Garanin, V.,Litvin, Y.Kudryavtsevaite - a new kimberlitic mineral.Mineralogical Magazine, Vol. 77, 3, pp. 327-334.TechnologyMineral chemistry
DS201708-1646
2017
Garanin, V.Garanin, V.The relationship among various morphological types of diamonds within diamond deposits in Russia: genesis, growth, dissolution and real diamond grade.11th. International Kimberlite Conference, PosterRussiadiamond morphology
DS1983-0594
1983
Garanin, V.G.Tatarintsev, V.I., Tsymbal, S.N., Garanin, V.G., Kudryatseva, G.Quenched Particles from Kimberlites of YakutiaDoklady Academy of Science USSR, Earth Science Section., Vol. 270, No. 1-6, PP. 144-148.RussiaPetrography
DS200512-0033
2002
Garanin, V.G.Ashchepkov, I.V., Vladykin, N.V., Mitchell, R.H., Coopersmith, H., Garanin, V.G.Geochemical features of the minerals from the heavy concentrate from KL-1 Kelsey lake kimberlite, State Line, Colorado: petrologic reconstruction.Deep Seated Magmatism, magmatism sources and the problem of plumes., pp. 163-173.United States, ColoradoGeochemistry - Kelsey Lake
DS1960-0638
1966
Garanin, V.K.Botkunov, A.I., Garanin, V.K., Kudryavtseva, G.P., Kharlamov, Ye.S.First find of syngenetic dolomite inclusions in zircon from the Mirkimberlite pipeDoklady Academy of Science USSR, Earth Science Section, Vol. 278, No. 1-6, pp. 161-164RussiaPetrology, Zircon
DS1975-0694
1978
Garanin, V.K.Bocharova, G.I., Garanin, V.K., Jilyaeva, V.A., Kudryavtseva, G.New Dat a on Exolution Lamellae in Picroilmenites from Jakutia Kimberlite Pipes.Jeol. News, Vol. 16E, No. 1, PP. 18-24.Russia, YakutiaMineralogy, Genesis, Kimberlite
DS1975-1026
1979
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Malkov, B.A.Mantle Inclusions in Diatremes of the Northeastern Party Of the Russian PlatformDoklady Academy of Science USSR, Earth Science Section., Vol. 249, No. 1-6, PP. 140-143.RussiaPetrography
DS1975-1027
1979
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Soshkina, L.T.Possible Applications of Thermomagnetic Analysis in Kimberlite Body Prospecting.Vses. Mineral O-vo Zap., No. 5, PP. 621-630.RussiaKimberlite, Geophysics
DS1981-0095
1981
Garanin, V.K.Botkunov, A.I., Garanin, V.K., et al.Sulfide Inclusions in Olivine from the Udachnaya Kimberlitepipe.Doklady Academy of Science USSR, Earth Science Section., Vol. 247, No. 1-6, PP. 113-117.RussiaPetrography
DS1981-0167
1981
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P.(the Nature of Heterogeneity in Ilmenite from Kimberlites.)Mineral. Zhur., Vol. 3, No. 1, PP. 75-83.RussiaKimberlite
DS1982-0215
1982
Garanin, V.K.Garanin, V.K., Kudriavtseva, G.P., et al.A New Variety of Eclogites in Yakutian KimberlitesDoklady Academy of Sciences Nauk SSSR., Vol. 262 , No. 6, PP. 1450-1455.RussiaKimberlite
DS1982-0216
1982
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Kharkiv, A.D., Chistyakova, V.K.New Varieties of Eclogite of Yakutia KimberlitesDoklady Academy of Sciences Nauk SSSR., Vol. 262, No. 6, PP. 1450-1455.RussiaMineralogy
DS1983-0239
1983
Garanin, V.K.Garanin, V.K., Krot, A.N., Kudryavtseva, G.P.Evolution of Peridotitic and Eclogitic Magmas in Kimberlitepipes.Geol. Rudn. Mest., Vol. 25, No. 4, PP. 14-28.RussiaKimberlite, Petrology, Geochemistry
DS1983-0240
1983
Garanin, V.K.Garanin, V.K., Kudriavtseva, G.P., Soshkina, L.T.Genesis of Ilmenite from KimberlitesDoklady Academy of Science USSR, Earth Science Section., Vol. 172, No. 1-6, MARCH PP. 102-106.RussiaGenesis, Petrography, Mineralogy
DS1983-0241
1983
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., et al.Mineralogy of the Ilmenite Bearing Hyperbasites of Mir Kimberlite Pipe.Academy of Science SSSR GEOL. SER. Bulletin., No. 2, PP. 84-95.RussiaMineralogy
DS1983-0242
1983
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., et al.Mineralogy of the Ilmenite Bearing Hyperbasites of the Mirkimberlite Pipe.Izv. Akad. Nauk Sssr, Geol. Ser., No. 2, FEBRUARY, PP. 84-95.Russia, YakutiaMineralogy
DS1983-0243
1983
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Kharkiv, A.D.First discovery of a deep rock of complex composition in the Udachnaya kimberlite pipe.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 269, No. 6, pp. 1449-1454RussiaBlank
DS1983-0244
1983
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Kharkiv, A.D., Chistyakova, V.K.New Eclogite Variety in Kimberlite Pipes of YakutiaDoklady Academy of Science USSR, Earth Science Section., Vol. 262, No. 1-6, PP. 147-151.Russia, YakutiaMir, Xenoliths, Inclusions, Chemical Analyses, Geochemistry
DS1983-0432
1983
Garanin, V.K.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
DS1984-0002
1984
Garanin, V.K.Afanasev, V.P., Varlamov, V.A., Garanin, V.K.The Abrasion of Minerals in Kimberlites in Relation to the Conditions and Distances of Their Transportation.Soviet Geology And Geophysics, Vol. 25, No. 10, OCTOBER PP. 112-117.RussiaMorphology, Petrography
DS1984-0165
1984
Garanin, V.K.Botkunov, A.I., Garanin, V.K., et al.Ist Occurrence of Syngenetic Inclusions of Dolomite in Zirconium from the Kimberlite Pipe, Mir.Doklady Academy of Sciences AKAD. NAUK SSSR., Vol. 278, No. 5, PP. 1214-1217.RussiaGenesis
DS1984-0290
1984
Garanin, V.K.Garanin, V.K.Ilmenite from Kimberlites.(russian)Moscow: Izd. Mosk.(Russian), 240p. Geological Society of Canada (GSC).RussiaMineralogy, Kimberlite
DS1984-0291
1984
Garanin, V.K.Garanin, V.K., Krot, A.N., Kudryavtseva, G.P.The Evolution of Peridotite and Eclogite Magmas in Kimberlite Pipes.International Geology Review, Vol. 26, No. 1, PP. 82-97.RussiaGenesis
DS1985-0075
1985
Garanin, V.K.Botkunov, A.I., Garanin, V.K., Krot, A.N., et al.Primary Hydrocarbon Inclusions in Garnets from the Mir and Sputnik Kimberlite Pipes.Doklady Academy of Sciences AKAD. NAUK SSSR., Vol. 280, No. 2, PP. 468-472.RussiaBlank
DS1985-0214
1985
Garanin, V.K.Garanin, V.K., Kudryavceva, G.P., Kharkiv, A.D.The Pecularities of Eclogites from Kimberlite Pipes in Yakutia.Terra Cognita., Vol. 5, No. 4, AUTUMN, P. 441-2, (abstract.).RussiaMineralogy
DS1985-0215
1985
Garanin, V.K.Garanin, V.K., Kudryavt, G.P., Kharkiv, A.D.Mineralogy of Ilmenitic Hyperbasaites from Obnazhennaya Kimberlite Pipe.Inzvest. Akad. Nauk, Geol. Ser., No. 5, MAY PP. 85-101.RussiaMineralogy
DS1985-0216
1985
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Kharkiv, A.D., Chistyakova, V.K.Mineralogy of ultrabasites with ilmenite of the Obnazhennaya kimberlitepipe.(Russian)Izves. Akad. Nauk SSSR, Ser. Geol.(Russian), No. 5, pp. 85-101RussiaPetrology, Mineralogy
DS1985-0217
1985
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Kharkiv, A.D., Chistyakova, V.K.Mineralogy of Ilmenitic Ultrabasic Rocks from the Obnazhennaya Kimberlite Pipe.Izv. Akad. Nauk Sssr Ser. Geol., No. 5, PP. 85-101.Russia, SiberiaMineralogy, Lherzolite
DS1986-0080
1986
Garanin, V.K.Bocharova, G.I., Garanin, V.K., Kudryavtseva, G.P.Sulfide mineralization in the kimberlite of YakutiaInternational Mineralogical Association Meeting, held Bulgaria Sept. 1982, Publishing in:, Vol. 13, pp. 107-119RussiaSulphides, Kimberlite
DS1986-0093
1986
Garanin, V.K.Botkunov, A.I., Garanin, V.K., Ivanova, T.N., Krot, A.N., KudryavtsevaOptical and colorimetric spectroscopic characteristics of garnets withNov. Dann. O Minetal. Moskva, (Russian), No. 33, pp. 120-129RussiaMineralogy, Garnet
DS1986-0094
1986
Garanin, V.K.Botkunov, 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
DS1986-0095
1986
Garanin, V.K.Botkunov, A.I., Garanin, V.K., Kudryavtseva, G.P., Kharlamov, Ye.S.First find of syngenetic dolomitic inclusions in zircon from the Mirkimberlite pipeDoklady Academy of Science USSR, Earth Science Section, Vol. 278, No. 1-6, April, pp. 161-164RussiaMineralogy
DS1986-0261
1986
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Krot, A.N.Role of sulfides in the evolution of mantle rocks of basic and ultrabasiccomposition and in the emergence of kimberlitebodiesProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 178-180RussiaBlank
DS1986-0262
1986
Garanin, V.K.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
DS1986-0263
1986
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Posukhova, T.V., Afanasjev, V.P.Morphology of kimberlite minerals: its usage for predicting and searchingfor diamond depositsProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 457-459RussiaDiamond exploration
DS1986-0264
1986
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Prewitt, C.T.Mineralogy of ilmenite from Yakutia kimberlites14th. International Meeting I.m.a., P. 109. (abstract.)RussiaKimberlite mineralogy, Ilmenite
DS1986-0265
1986
Garanin, V.K.Garanin, V.K., Zhilyaeva, V.A., Kudyavtskaya, G.P., Savrasov, D.I.Fanciful cuts created by laser sawingGems and Gemology, Vol. XXII Fall, p. 170GlobalDiamond cutting
DS1986-0266
1986
Garanin, V.K.Garanin, V.K., Zhilyaeva, V.A., Kudyavtskaya, G.P., Savrasov, D.I.Mineralogical factors of magnetism of kimberlite rocks.(Russian)Izvest. Annual Nauka Geol., (Russian), No. 11, November pp. 82-100RussiaGeophysics
DS1987-0068
1987
Garanin, V.K.Botkunov, A.I., Garanin, V.K., Krot, A.N., Kudryavtseva, G.P.Garnet mineral inclusions in kimberlites of Yakutia,their genetic and practical importance.(Russian)Geol. Rudyn. Mestoroz., (Russian), Vol. 29, No. 1, pp. 15-29Russia, Anabar shieldMineral inclusions, Petrology
DS1987-0069
1987
Garanin, V.K.Botkunov, A.I., Garanin, V.K., Krot, A.N., Kuryavtseva, G.P.Mineral inclusions in garnets from Yakutian kimberlites and their genetic and practical significance.*rusGeol. Rudn. Mestorozhd. *rus, Vol. 20, No. 1, pp. 15-29RussiaMineralogy
DS1987-0235
1987
Garanin, V.K.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
DS1987-0236
1987
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Mikhailichencko, O.A.Vertical zoning in the Mir kimberlite pipes.(Russian)Geol. Rudn. Mestorozhd., (Russian), Vol. 29, No. 5, pp. 11-26RussiaBlank
DS1987-0237
1987
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Mikhailichenko, O.A.Rapid thermomagnetic analysis of kimberlites and estimation oftheirproductivity.(Russian)Vestn. Mosk. University of Ser. 4, Geol., (Russian), No. 2, pp. 41-49RussiaGeothermometry
DS1987-0238
1987
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Mikhailichenko, O.A.Rapid thermomagnetic analysis of the study of kimberlites and evaluation of their productivityMoscow University of Geol. Bulletin, Vol. 42, No. 2, pp. 40-47RussiaBlank
DS1987-0239
1987
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Mikhaylichenko, A.Vertical zoning of the kimberlite Mir pipe.(Russian)Geol. Rudny. Mestord., (Russian), Vol. 29, No. 5, pp. 11-26RussiaPetrology, Geothermometry
DS1987-0348
1987
Garanin, V.K.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
DS1987-0349
1987
Garanin, V.K.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
DS1987-0445
1987
Garanin, V.K.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
DS1988-0236
1988
Garanin, V.K.Garanin, V.K., Guseva, E.V., Dergach, D.V.Diamond crystals in garnets from granite gneisses.(Russian)Doklady Academy of Sciences Nauk USSR, (Russian), Vol. 298, No. 1, pp. 190-194GlobalBlank
DS1989-0460
1989
Garanin, V.K.Galimov, E.M., Botkunov, A.I., Garanin, V.K.Carbon bearing fluid inclusions in olivine and garnet from the Udachnaya kimberlite pipe.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 7, pp. 1011-1015RussiaDiamond inclusions, Garnet analyses
DS1989-0461
1989
Garanin, V.K.Galimov, E.M., Botkunov, A.I., Garanin, V.K., Spasennykh, M. Yu.Carbon-containing fluid inclusions in garnet and olivine from Kimberlites of the Udachnaya pipe. (USSR)(Russian)Geochemistry International (Geokhimiya), (Russian), No. 7, pp. 1011-1015RussiaFluid inclusions, Garnet
DS1989-0471
1989
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Mikhaylichenko, O.A., SaparinDiscreteness of the natural diamond formation process. (Russian)Mineral. Zhurnal., (Russian), Vol. 11, No. 31, pp. 3-19RussiaDiamond morphology, Natural diamond
DS1989-0772
1989
Garanin, V.K.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
DS1989-1552
1989
Garanin, V.K.Verzhak, V.V., Garanin, V.K., Kudryavtseva, G.P., MikhailenkoTo the problem of diamond potential relationship to the mineral composition of kimberlites and lamproites.(Russian)Geol. Rudn. Mestorozhd., (Russian), Vol. 31, No. 2, pp. 15-27RussiaKimberlite, Lamproite
DS1989-1553
1989
Garanin, V.K.Verzhak, V.V., Garanin, V.K., Kudryavtseva, G.P., MikhailichenkoTo the problem of diamond potential relationship to the mineral composition of kimberlites andlamproites.(in Russian)Geol. Rudn. Mestorozh., (Russian), Vol. 31, No. 2, Mar-Apr. pp. 15-27RussiaLamproites, Diamond potential
DS1989-1554
1989
Garanin, V.K.Verzhak, V.V., Garanin, V.K., Kudryavtseva, G.P., MikhaylichenkoMineralogic composition of kimberlites and lamproites as an indicator of diamond potentialInternational Geology Review, Vol. 31, No. 5, pp. 484-495RussiaLamproites, Kimberlites, Mineralogy -diamond poten
DS1990-0258
1990
Garanin, V.K.Busheva, E.B., Vasiljeva, E.R., Garanin, V.K., KudrjavtsevaMineralogy of kimberlites of the northern European part of the USSRInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 786-788RussiaKimberlites, Mineralogy
DS1990-0505
1990
Garanin, V.K.Galimov, E.M., Botkunov, A.I., Garanin, V.K.Carbon bearing fluid inclusions in olivine and garnet from Udachnaya pipekimberlitesGeochemistry International, Vol. 27, No. 2, February pp. 87-90RussiaGeochronology, Carbon inclusions
DS1990-0513
1990
Garanin, V.K.Garanin, V.K.The problem of discreteness in the natural diamond formationprocess.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 5, October pp. 28-36RussiaDiamond morphology, Natural diamond
DS1990-0514
1990
Garanin, V.K.Garanin, V.K.Some new dat a on conditions of zircon formation from kimberlitesMoscow University of Geol. Bulletin, Vol. 45, No. 6, pp. 43-54RussiaKimberlites, Petrography-eclogites, zircon
DS1990-0515
1990
Garanin, V.K.Garanin, V.K., Kasimova, R., Kudryavtseva, G.P., MikhajlichenkoMineralogy of spinels from kimberlites and lamproitesInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 31-32RussiaMineralogy -spinels, Lamproites, kimberlites
DS1990-0516
1990
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P.Morphology, physical properties and paragenesis of inclusion -bearing diamonds from Yakutian kimberlitesLithos, Vol. 25, No. 1-3, November pp. 211-218RussiaDiamond inclusions, Diamond morphology
DS1990-0517
1990
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P.The discretion of the natural diamond formation processInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 675-676RussiaDiamond morphology, Diamond genesis
DS1990-0518
1990
Garanin, V.K.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
DS1990-0519
1990
Garanin, V.K.Garanin, V.K., Titkov, S.V.About etching patterns on diamond crystals from north European part of the USSR (technical note). (Russian)Izv. Akad. Nauk SSS*(in Russian), No. 9, September pp. 110-115RussiaDiamond morphology, Etching patterns
DS1990-0520
1990
Garanin, V.K.Garanin, V.K., Zhiljaeva, V.A., Kudrjavtseva, G.P., MikhailichenkoMineralogy of ferrimagnetic oxides and magnetic properties of Kimberlites and lamproitesInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 29-30RussiaMineralogy -oxides, Lamproites, kimberlites
DS1990-0521
1990
Garanin, V.K.Garanin, V.K., Zhukov, G.D., Kudrjavtseva, G.P., Laverova, T.N.Mineralogy of garnets with inclusions from Sitikanskaja kimberlite pipeInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 799-801RussiaMineralogy -garnets, Sitikanskaja
DS1990-1505
1990
Garanin, V.K.Varlamov, D.A., Garanin, V.K., Kudrjavtseva, G.P.Mineral inclusions in high grade metamorphism garnetsInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 896-897RussiaMicroscopy, Diamond inclusions
DS1991-0114
1991
Garanin, V.K.Bezborodov, S.M., Garanin, V.K., Kudrjavtseva, G.P., Schepina, N.A.The pecularities of the mineral composition of the diamond bearing eclogites from the Udachnaya kimberlite pipeProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 481-483RussiaDiamond morphology, Garnet composition
DS1991-0115
1991
Garanin, V.K.Bezborodov, S.M., Garanin, V.K., Kudryavtseva, G.P., et al.Mineralogy of the diamond bearing eclogites from the Udachnaya kimberlitepipe.(Russian)Mineral. Zhurn., (Russian), Vol. 13, No. 3, pp. 24-35Russia, YakutiaMineralogy, Deposit -Udachnaya
DS1991-0116
1991
Garanin, V.K.Bezborodov, S.M., Garanin, V.K., Kudryavtseva, G.P., Ponailo, I.Discovery of eclogite with generations of diamond in the Udachnaya kimberlite pipe. (Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 317, No. 3, pp. 714-717RussiaDiamond genesis, Eclogite
DS1991-0137
1991
Garanin, V.K.Bogatikov, O.A., Garanin, V.K., Kononova, K.A., Kudrjavtseva, G.P.Ore minerals from the lamproite ground massProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 484-485Russia, Australia, SpainOxide mineral chemistry, Diamond evaluation
DS1991-0191
1991
Garanin, V.K.Bulanova, B., Varlamov, D.A., Garanin, V.K., Kudjavtseva, G.P.Chemico-genetic classification of the most important minerals-satellites Of the diamondProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 490-491RussiaMineral chemistry, Genesis
DS1991-0532
1991
Garanin, V.K.Garanin, V.K., Kudrjavtseva, G.P.New technology of the searching of the diamond bearing kimberlites methodological basis and fields of applicationsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 505-507RussiaDiamond evaluation, Diamond genesis
DS1991-0533
1991
Garanin, V.K.Garanin, V.K., Kudrjavtseva, G.P., Laverova, T.N.The comparative characteristics of ilmenite from the kimberlite Provinces of the USSRProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 508-509RussiaIlmenite, Mineral chemistry
DS1991-0534
1991
Garanin, V.K.Garanin, V.K., Kudrjavtseva, G.P., Michailichchenko, O.A.Mineralogy of oxides from the ground mass of kimberlites of Yakutia and northern European part of the USSRProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 510-512RussiaMineralogy, Oxides
DS1991-0923
1991
Garanin, V.K.Kostrovitsky, S.I., Garanin, V.K.Chrome titanate inclusions of unusual composition in pyropes from lamprophyres and kimberlitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 525-526RussiaGarnet inclusions, Mineral chemistry
DS1991-1751
1991
Garanin, V.K.Trukhin, V.I., Verichev, E.M., Garanin, V.K., Zhilyayeva, V.A.Magnetomineralogy of kimberlite type rocks at the South European part Of the USSR.(Russian)Izvest. Akad. Nauk SSSR, (Russian), No. 7, July pp. 39-51RussiaKimberlite, Mineralogy, geophysics, magnetics
DS1992-0514
1992
Garanin, V.K.Garanin, V.K.Mineralogical zonality of kimberlitesProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 2, abstract p. 579RussiaKimberlites, Mineralogy
DS1993-0116
1993
Garanin, V.K.Bezborodov, S.M., Garanin, V.K., Kudryavtseva, G.P., Ponahlo, J.Find of eclogite with two diamond generations in the Udachnaya kimberlitepipeDoklady Academy of Sciences USSR, Earth Science Section, Vol. 317 A February Publishing date pp. 190-194Russia, YakutiaDiamond morphology, Deposit -Udachnaya
DS1993-0481
1993
Garanin, V.K.Garanin, V.K., et al.Oxide minerals and magnetic properties of lamproites from AustraliaMoscow University of Geol. Bulletin, Vol. 48, No. 3, pp. 46-58.AustraliaLamproites
DS1993-0482
1993
Garanin, V.K.Garanin, V.K., et al.Oxide minerals and magnetic properties of lamproites from Spain andRussia.Moscow University of Geol. Bulletin, Vol. 48, No. 3, pp. 37-47.GlobalLamproites
DS1993-0483
1993
Garanin, V.K.Garanin, V.K., Kasimova, F.I., Melnikov, F.P.New minerals-inclusions in zircons from the kimberlite pipe- Mir. (Russian)Doklady Academy of Sciences Akad. Nauk, (Russian), Vol. 330, No. 1, May pp. 75-78Russia, YakutiaMineral inclusions, Deposit -Mir
DS1993-0484
1993
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Janse, A.J.A.Vertical and horizontal zoning of kimberlitesPreprint, 14p.Russia, Yakutia, Arkangelsk, South AfricaZonation, Kimberlites
DS1994-0572
1994
Garanin, V.K.Garanin, V.K., et al.The diamond mineral indicators paragenesis with hydrocarbonates from the Yakutian kimberlites.9th. IAGOD held Beijing, Aug.12-18., p. 701-703. abstractRussia, YakutiaDiamond genesis, Deposit -Mir
DS1994-0573
1994
Garanin, V.K.Garanin, V.K., et al.Temperature of formation of zircon and its paragenetic association with the Mir kimberlite pipe.(Russian)Izvest. Vysshikh-Uchebnykh Zavedeniy Geol. i Raz., (Russian), No. 1, pp. 67-70.Russia, YakutiaZircon mineralogy, Deposit -Mir
DS1994-0958
1994
Garanin, V.K.Kudrjavtseva, G.P., Garanin, V.K.New dat a on the internal structure of diamond and its genesisInstitute of Mining and Metallurgy (IMM) Bulletin, Economic Geology in Europe and Beyond- abstracts of meeting, p. B196, abstract only.GlobalDiamond morphology
DS1995-0581
1995
Garanin, V.K.Garanin, V.K., Kasimova, F.I., Melnikov, F.P.New inclusion minerals from zircons in the Mir kimberlite pipeDoklady Academy of Sciences Acad. Science Russia, Vol. 331, No. 5, May pp. 54-59.RussiaMineralogy -zircons, Deposit -Mir
DS1995-0582
1995
Garanin, V.K.Garanin, V.K., Posukhova, T.V.Morphology and growth history of diamonds in Arkhangelsk kimberlite pipeProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 175-6.Russia, ArkangelskDiamond morphology, Deposit - Zolotitskoye, Verhotinskoye, Kepinskoye
DS1995-0583
1995
Garanin, V.K.Garanin, V.K., Posukhova, T.V.Typomorphism of microcrystalline oxides from kimberlite groundmass in Arkhangel kimberlite province.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 177-8.Russia, ArkangelskDiamond morphology, Deposit - Zolotitskoye, Verhotinskoye, Kepinskoye
DS1996-0144
1996
Garanin, V.K.Bobrov, A.V., Garanin, V.K.Mineralogy and genesis of pyrope peridotite zonal modulesMoscow University of Geol. Bulletin., Vol. 51, No. 1, pp. 27-36.RussiaPeridotite
DS1996-0479
1996
Garanin, V.K.Garanin, V.K., Kasimva, F.I., Melnikov, F.P.Hydrocarbon inclusions in zircon from the Mir kimberlite pipeDoklady Academy of Sciences, Vol. 336, pp. 187-189.Russia, YakutiaInclusions -zircon, Deposit -Mir
DS1996-0778
1996
Garanin, V.K.Kostrovitsky, S.I., Garanin, V.K.The composition of picroilmenite as an indicator of zonation of the kimberlite pipes clusters.International Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 393.RussiaMineralogical mapping, Clusters
DS1996-1468
1996
Garanin, V.K.Varlamov, D.A., Garanin, V.K., Kostrovitsky, S.I.Exotic high titanium minerals as inclusions in garnets from lower crustaland mantle xenoliths.Doklady Academy of Sciences, Vol. 345A, No. 9, Oct. pp. 352-355.Russia, YakutiaXenoliths, Deposit - International, Sytykan
DS1996-1472
1996
Garanin, V.K.Vasilyeva, E.R., Garanin, V.K., Kadryavtseva, G.P.Mineralogy of garnets from kimberlites of Arkangelsk diamond bearingprovince.International Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 386.RussiaGarnet mineralogy, Kimberlites
DS1997-0368
1997
Garanin, V.K.Garanin, V.K., Dummett, Amtauer, Kudryavtseva, FipkeInternal structure and spectroscopic characteristics of diamonds from Lomonosov deposit.Doklady Academy of Sciences, Vol. 353, No. 2, Feb-Mar, pp. 233-5.Russia, Kola PeninsulaDiamond - morphology, Deposit - Lomonosov
DS1997-0369
1997
Garanin, V.K.Garanin, V.K., Kudryavtseva, G.P., Posukhova, T.V.Indicators of diamond preservation in kimberlitePapunen: 4th. Biennial SGA Meeting, pp. 767-770.Russia, ArkangelskDiamond exploration, Thermodynamics, microcrystalline oxides
DS1998-0148
1998
Garanin, V.K.Bovkun, A.V., Garanin, V.K., Kudriavtseva, PossuklovaChemical genetic classification of microcrystalline oxides from kimberlite groundmass - system prospecting7th International Kimberlite Conference Abstract, pp. 91-93.Russia, Arkangelsk, Kola PeninsulaMicroprobe analyses, Deposit - Zolitskoye, Verkhotinskoye, Kepinskoye, Touri
DS1998-0149
1998
Garanin, V.K.Bovkun, A.V., Garanin, V.K., Kudriavtseva, PossuklovaDiamonds from Timan placers: morphology, spectroscopy and genesis7th International Kimberlite Conference Abstract, pp. 97-99.Russia, TimanPLacers, alluvials, Diamond morphology - types
DS1998-0150
1998
Garanin, V.K.Bovkun, A.V., Garanin, V.K., Kudriavtseva, PossuklovaChemical genetic classification of oxides from kimberlite groundmass as basis - evaluation of diamond7th International Kimberlite Conference Abstract, pp. 94-96.Russia, Yakutia, AikalHigh magnesian - spinels, Deposit - Obnazhenna, Mir, Udachnaya, Morkokka
DS1998-0466
1998
Garanin, V.K.Garanin, V.K., et al.Geological structure, mineralogical and petrological characteristics of theM.V. Lomonosov diamond deposit.Preprint submitted to Min. Deposita, approx. 35p. 17 textRussia, Arkangelsk, Kola PeninsulaMineralogy, petrology, Deposit - Lomonosov
DS1998-0467
1998
Garanin, V.K.Garanin, V.K., Kudriavtseva, G.P.Diamonds from the M.V. Lomonosov deposit, Arkangelsk diamondiferousprovince.Ima 17th. Abstract Vol., p. A15. poster abstractRussia, Arkangelsk, Kola PeninsulaDiamond morphology, Deposit - Lomonosov
DS1998-0468
1998
Garanin, V.K.Garanin, V.K., Kudriavtseva, G.P., Possukhova, T.V.Diamonds of Arkhangelsk kimberlite province ( review)7th International Kimberlite Conference Abstract, pp. 233-235.Russia, Arkangelsk, Kola PeninsulaDiamond morphology, Deposit - Lomonosov
DS1998-0469
1998
Garanin, V.K.Garanin, V.K., Kudriavtseva, G.P., Vasilyeva, E.R.The fundamental study of garnets: application for prospecting and economical estimation - diamond bearing7th International Kimberlite Conference Abstract, pp. 236-8.Russia, Arkangelsk, Kola PeninsulaGarnet mineralogy, Deposit - Zolitsky, Verkhotinsky
DS1998-0470
1998
Garanin, V.K.Garanin, V.K., Posukhova, T.V.Unusual diamonds from Arkhangelsk kimberlite provinceIma 17th. Abstract Vol., p. A15. poster abstractRussia, Arkangelsk, Kola PeninsulaDiamond morphology, Deposit - Pioneerskaya
DS1998-0471
1998
Garanin, V.K.Garanin, V.K., Zvezdin, A.V., Okrugin, G.V.Mineralogy of oxide minerals from Morkoka pipe kimberlites (Yakutian diamond Province): implications for diamond potential evaluation.Moscow University of Geol. Bulletin., Vol. 53, No. 4, pp. 24-36.Russia, YakutiaDeposit - Morkoka
DS1999-0563
1999
Garanin, V.K.Possoukhova, T.V., Kudryavtseva, G.P., Garanin, V.K.Diamonds and accompanying minerals from Arkangelsk kimberlite, RussiaStanley, SGA Fifth Biennial Symposium, pp. 667-70.Russia, Arkangelsk, Kola PeninsulaMineralogy, Deposit - Arkangel
DS2001-0356
2001
Garanin, V.K.Garanin, V.K., Gonzaga, G., Campos, J., Kudryavtseva, G.A new theory of the glacial origin of diamond placers in the Ural regionMoscow University of Geol. Bulletin., Vol. 55, No. 5, pp. 54-8.Russia, UralsAlluvials - placers, Geomorphology
DS2001-0357
2001
Garanin, V.K.Garanin, V.K., Kudryavtseva, Possoukhova, TikhovaTwo types of the Diamondiferous kimberlites from the Arkangelsk province, RussiaMineral deposits 21st. century, pp. 955-8.Russia, ArkangelskTectonics, Deposit - Zolotitsa
DS2001-1052
2001
Garanin, V.K.Serov, I.V., Garanin, V.K., Zinchuk, N.N., Rotman, A.Ye.Mantle sources of the kimberlite volcanism of the Siberian PlatformPetrology, Vol.9, No. 6, pp. 576-88.Russia, Siberia, YakutiaGeochemistry - major, trace, ratios, mantle metasomatism, analyses, Deposit - Middle Markha, Daldyn-Alakit, Upper Muna
DS2003-0125
2003
Garanin, V.K.Bobrov, A.V., Verichev, E.M., Garanin, V.K., Garanin, K.V., Kudryavtseva, G.P.Xenoliths of mantle metamorphic rocks from the Diamondiferous V. Grib pipe (8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, POSTER abstractRussia, ArkangelskDeposit - Grib
DS2003-0745
2003
Garanin, V.K.Kostrovitsky, S.I., Verichev, E.M., Garanin, V.K., Suvorova, L.V., AschepkovMegacrysts from the Grib kimberlite Arkangelsk Province8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractRussia, Kola Peninsula, ArkangelskDeposit - Grib
DS2003-1423
2003
Garanin, V.K.Verichev, E.M., Garanin, V.K., Kudryavtseva, G.P.Geology, composition, conditions of formation and technique of exploration of theGeology of Ore Deposits, Vol. 45, 4, pp. 337-361.Russia, Arkangelsk, Kola PeninsulaGenesis - Grib, comparison with Lomonosov
DS200412-0173
2003
Garanin, V.K.Bobrov, A.V., Verichev, E.M., Garanin, V.K., Garanin, K.V., Kudryavtseva, G.P.Xenoliths of mantle metamorphic rocks from the Diamondiferous V. Grib pipe ( Arkangelsk province): petrology and genetic aspects8 IKC Program, Session 6, POSTER abstractRussia, Kola Peninsula, ArchangelMantle petrology Deposit - Grib
DS200412-1048
2004
Garanin, V.K.Kostrovitsky, S.I., Malkovets, V.G., Verichev, E.M., Garanin, V.K., Suvorova, L.V.Megacrysts from the Grib kimberlite pipe ( Arkandgelsk Province, Russia).Lithos, Vol. 77, 1-4, Sept. pp. 511-523.Russia, Archangel, Kola PeninsulaHigh chromium association, genesis
DS200412-1049
2003
Garanin, V.K.Kostrovitsky, S.I., Verichev, E.M., Garanin, V.K., Suvorova, L.V., Aschepkov, I.V., Mlovets, V., Griffin, W.L.Megacrysts from the Grib kimberlite Arkangelsk Province.8 IKC Program, Session 7, POSTER abstractRussia, Kola Peninsula, ArchangelKimberlite petrogenesis Deposit - Grib
DS200412-2054
2003
Garanin, V.K.Verichev, E.M., Garanin, V.K., Kudryavtseva, G.P.Geology, composition, conditions of formation and technique of exploration of the Vladimir Grib kimberlite pipe, a new diamond dGeology of Ore Deposits, Vol. 45, 4, pp. 337-361.Russia, Kola Peninsula, ArchangelGenesis - Grib, comparison with Lomonosov
DS200512-0026
2005
Garanin, V.K.Appollonov, V.N., Verzhak, V.V., Garanin, K.V., Garanin, V.K., Kudryavtseva, G.P., Shlykov, V.G.Saponite from the Lomonosov diamond deposit.Moscow University Geology Bulletin, Vol. 59, 2, pp. 69-84.Russia, Kola Peninsula, ArchangelGeology
DS200512-0096
2005
Garanin, V.K.Bobrov, A.V., Verichev, E.M., Garanin, V.K., Kudryavtseva, G.P.The first find of kyanite eclogite in the V. Grib kimberlite pipe ( Arkangelsk Province).Doklady Earth Sciences, Vol. 402, 4, pp. 628-631.Russia, Kola Peninsula, ArchangelEclogite
DS200712-0286
2007
Garanin, V.K.Egorov, K.N., Ramnko, E.F., Podvysotsky, V.T., Sabulukov, S.M., Garanin, V.K., Dyakonov, D.B.New dat a on kimberlite magmatism in southwestern Angola.Russian Geology and Geophysics, Vol. 48, 4, pp. 323-336.Africa, AngolaMagmatism - kimberlites
DS200812-0380
2008
Garanin, V.K.Galimov, E.M., Palazhchenko, O.V., Verichev, E.M., Garanin, V.K., Golovin, N.N.Carbon isotope composition of diamonds from the Archangelsk diamond province.Geochemistry International, Vol. 46, 10, pp. 961-970.Russia, Archangel, Kola PeninsulaDiamond chemistry
DS200812-0386
2008
Garanin, V.K.Garanin, V.K., Kopchikov, M.B., Verichev, E.M., Golovin, N.N.New dat a on the morphology of diamonds from tholeiite basalts of the Zimneberezhnyi ( winter Coast) area of the Arkangelsk Diamondiferous province.Moscow University Geology Bulletin, Vol. 63, 2, March-April pp. 114-118.Russia, Archangel, Kola PeninsulaDiamond morphology
DS200812-0561
2008
Garanin, V.K.Khachatryan, G.K., Palazhchenko, O.V., Garanin, V.K., Ivannikov, P.V., Verichev, E.M.Origin of disequilibrium diamond crystals from Parpinsky 1 kimberlite pipe using dat a from cathode luminescence and infra red spectroscopy.Moscow University Geology Bulletin, Vol. 63, 2, March-April pp. 86-94.RussiaDiamond morphology
DS200812-0839
2008
Garanin, V.K.Palazhchenko, O.V., Garanin, V.K., Galimov, E.M.Isotope and mineralogical study of diamonds from northwestern Russia.Goldschmidt Conference 2008, Abstract p.A718.Russia, Kola Peninsula, ArchangelDeposit - Lomonosov, Grib
DS200912-0372
2009
Garanin, V.K.Khachatryan, G.K., Kopchikov, M.B., Garanin, V.K., Chukichev, M.V., Golovin, N.N.New dat a of typomorphic features of diamonds from placers in North Timan.Moscow University Geology Bulletin, Vol. 64, 2, pp. 102-110.Russia, AsiaDiamond morphology, crystallography, IR spectroscopy
DS200912-0651
2009
Garanin, V.K.Rubanova, E.V., Palazhenko, O.V., Garanin, V.K.Diamonds from the V. Grib pipe, Arkangelsk kimberlite province, Russia.Lithos, In press availableRussia, Archangel, Kola PeninsulaDeposit - Grib
DS201012-0354
2008
Garanin, V.K.Khachatryan, G.K., Palazhchenko, O.V., Garanin, V.K., Ivannikov, P.V., Verichev, E.M.Origin of disequilibrium diamond crystals from Karpinsky - 1 kimberlite pipe using dat a from cathode luminescence and infra red spectroscopy.Moscow University Geology Bulletin, Vol. 63, pp. 86-94.RussiaSpectroscopy
DS201112-0553
2011
Garanin, V.K.Kriulina, G.Yu., Garanin, V.K., Rotman, A.Ya., Kovalchuk, O.E.Pecularities of diamonds from the commercial deposits of Russia.Moscow University Geology Bulletin, Vol. 66, 3, pp. 171-183.Russia, Yakutia, Kola PeninsulaArkhangelsk, Grib, Lomonosov, Mir, Internationalnaya
DS201112-0970
2011
Garanin, V.K.Sirotkina, E.A., Bobrov, A.V., Garanin, V.K., Bovkun, A.V., Shkurskii, B.B., Korost, D.V.Pyroxene and olivine exsolution textures in majoritic garnets from the Mir kimberlitic pipe, Yakutia.Goldschmidt Conference 2011, abstract p.1885.RussiaMir
DS201212-0077
2012
Garanin, V.K.Bobrov, A.V., Sirotkina, E.A., Garanin, V.K., Bovkun, A.V., Korost, D.V., Shkurski, B.B.Majoritic garnets with exsolution textures from the Mir kimberlitic pipe ( Yakutia)Doklady Earth Sciences, Vol. 444, 1, pp. 574-578.Russia, YakutiaDeposit - Mir
DS201212-0084
2012
Garanin, V.K.Bovkun, A.V., Biller, A.Y., Skvortsova, V.L., Garanin, V.K.Polyphase hydrocarbon inclusions in garnet from the Mir pipe ( Yakutia, Russia).10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Mir
DS201212-0229
2012
Garanin, V.K.Garanin, V.K., Anashkin, S.M., Bovkun, A.V., Jelsma, H., Shmakov, I.I., Garanin, K.V.Groundmass microcrystalline oxides from the Marsfontein pipe ( RSA) , Catoca, Camachia and other Angolan kimberlite pipes.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, Angola, South AfricaDeposit - Marsfontein, Catoca, Camachia
DS201212-0438
2012
Garanin, V.K.Malkovets, V.G., Griffin, W.L., Pearson, N.J., Rezvukhin, D.I., Oreilly, S.Y., Pokhilenko, N.P., Garanin, V.K., Spetsius, Z.V., Litasov, K.D.Late metasomatic addition of garnet to the SCLM: Os-itope evidence.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleMetasomatism
DS201212-0659
2012
Garanin, V.K.Sirotkina, E.A., Bobrov, A.V., Garanin, V.K., Bovkin, A.V., Shkurski, B.B., Korost, D.V.Exsolution textures in majoritic garnets from the Mir kimberlite pipe, Yakutia, Russia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Mir
DS201212-0733
2012
Garanin, V.K.Tretyachenko, W., Bovkun, A.V., Garanin, K.V., Garanin, V.K., Tretyachenko, N.G.Formation features of the early Hercynic alkaline ultrabasic and basic volcanic complexes from Zimny Bereg area, north east of Archangelsk region, Russia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, Archangel, Kola PeninsulaAlkalic
DS201312-0019
2013
Garanin, V.K.Anashkin, S.M., Bovkum, A.V., Litvin, Yu.A., Garanin, V.K.the intraplate character of supercontinent tectonics.Doklady Earth Sciences, Vol. 451, 2, pp. 849-854.MantleTectonics
DS201412-0267
2014
Garanin, V.K.Garanin, V.K., Bovkun, A.V., Garanin, K.V., Kriulina, G.Y., Iwanich, W.Diamonds and its grade in different petrochemical types of kimberlites ( based on Russian diamond deposits).6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 4p. AbstractRussiaMineral chemisty
DS201412-0268
2014
Garanin, V.K.Garanin, V.K., Garanin, K.V., Iwanuch, W.Polygenesis and discreteness of diamond formation. 6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 1p. AbstractGlobalDiamond genesis
DS201412-0269
2014
Garanin, V.K.Garanin, V.K., Garanin, K.V., Iwanuch, W.Diamonds from Russia. History6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 5p. AbstractRussiaHistory and discoveries
DS201412-0270
2014
Garanin, V.K.Garanin, V.K., Garanin, K.V., Kriulina, G.Y.Granitoids of different geochemical types of Baikal area: their diamonds from Russia.30th. International Conference on Ore Potential of alkaline, kimberlite and carbonatite magmatism. Sept. 29-, http://alkaline2014.comRussiaDiamonds