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SDLRC - Scientific Articles all years by Author - Be-Bk


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 - Be-Bk
Posted/
Published
AuthorTitleSourceRegionKeywords
DS1998-0424
1998
Bea, F.Fershtater, G.B., Bea, F., Montero, M.P.Anatexis of basites in a Paleosubduction Zone and the origin of anorthosite-plagiogranite series Urals....Geochemistry International, Vol. 36, No. 8, Aug. 1, pp. 684-97.Russia, UralsBasites, Platinum, belt, platinum group elements (PGE), Alkaline rocks
DS1999-0824
1999
Bea, F.Zangana, N.A., Downes, H., Bea, F.Geochemical variation in peridotite xenoliths and their constituent clinopyroxenes from Ray Pic: implicationsChemical Geology, Vol. 153, No. 1-4, Jan. pp. 11-36.Europe, French Massif CentralMantle - shallow lithosphere
DS2000-0862
2000
Bea, F.Scarrow, J.H., Bea, F., Montero, P., Fershtater, G.Preservation of atypical arc rocks in suturesIgc 30th. Brasil, Aug. abstract only 1p.GlobalSubduction, Tectonics - adakitic
DS2001-0051
2001
Bea, F.Arzamastsevm A.A., Bea, F., Glaznev, V.N., Arzamasteva, L.V., Montero, P.Kola alkaline province in the Paleozoic: evaluation of primary mantle magma composition and magma generation conditions.Russian Journal of Earth Science, Vol. 3, 1, March, pp.Russia, Kola PeninsulaMagmatism
DS2001-0094
2001
Bea, F.Bea, F., Arzamastev, A., Arzamastseva, L.Anomalous alkaline rocks of Soustov, Kola: evidence of mantle derived metasomatic fluids affecting crustal ..Contributions to Mineralogy and Petrology, Vol. 140, No. 5, pp. 554-66.Russia, Kola PeninsulaMetasomatism
DS2002-0067
2002
Bea, F.Arzamastsev, A.A., Bea, F., Arzamasteva, L.V., Montero, P.Rare earth elements in rocks and minerals from alkaline plutons of the Kola Peninsula, NW Russia, as indicators of alkaline magma evolution.Russian Journal of Earth Science, Vol. 4, 3, JuneRussia, Kola PeninsulaREE
DS2002-0125
2002
Bea, F.Bea, F., Fershtater,Montero, Whitehouse, Levin, ScarrowRecycling of continental crust into the mantle as revealed by Kytlym dunite zircons, Ural Mountains.Terra Nova, Vol. 13, No. 6, pp. 407-12.RussiaSubduction
DS200512-0029
2002
Bea, F.Arzamastsev, A.A., Bea, F., Arzamastseva, L.V., Montero, P.Devonian plume magmatism in the NE Baltic Shield: rare earth elements in rocks and minerals of ultrabasic alkaline series as indicators of magma evolution.Deep Seated Magmatism, magmatism sources and the problem of plumes., pp. 42-68.Baltic Shield, Kola Peninsula, RussiaMagmatism
DS200612-0041
2006
Bea, F.Arzamastev, A.A., Bea, F., Arzamastseva, L.V., Montero, P.Proterozoic Gremyakha-Vyrmes polyphase massif, Kola Peninsula: an example of mixing basic and alkaline mantle melts.Petrology, Vol. 14, 4, pp. 361-389.Russia, Kola PeninsulaAlkalic
DS200612-0042
2006
Bea, F.Arzamastsev, A.A., Bea, F., Arzamasteva, L.V., Montero, P.Proterozoic Gremyakha Vyrmes polyphase massif, Kola Peninsula: an example of mixing basic and alkaline melts.Petrology, Vol. 14, 4, pp. 361-389.Russia, Kola PeninsulaAlkalic
DS200712-0115
2006
Bea, F.Brown, D., Puchkov, V., Alvarez Marron, J., Bea, F., Perez Estaun, A.Tectonic processes in the southern and middle Urals: an overview.Geological Society of London Memoir, No. 32, pp. 407-420.Russia, Europe, UralsTectonics
DS201312-0029
2012
Bea, F.Arzamastsev, A.A., Bea, F., Arzmastseva, L.V., Monero, P., Elizarova, I.R.Trace elements in minerals as indicators of mineral evolution: the results of L ICP MS study.Vladykin, N.V. ed. Deep seated magmatism, its sources and plumes, Russian Academy of Sciences, pp. 110-132.TechnologyMineralogy - indicators
DS201312-0061
2012
Bea, F.Bea, F., Montero, P., Haissen, F., El Archi, A.2.46 Ga kasilite and nepheline syenites from the Awsard plution, Reguibat Rise of the West African Craton, Morocco. Generation of extremely K-rich magmas at the Archean-Proterozoic transition.Precambrian Research, Vol. 224, pp. 242-254.Africa, MoroccoUltrapotassic rocks
DS201603-0401
2016
Bea, F.Montero, P., Haissen, F., Mouttaqi, A., Molina, J.F., Errami, A., Sadki, O., Cambeses, A., Bea, F.Contrasting SHRIMP U-Pb zircon ages of two carbonatite complexes from the peri-cratonic terranes of the Reguibat shield: implications for the lateral extension of the West African Craton.Gondwana Research, in press available 13p.Africa, West AfricaCarbonatite

Abstract: The Oulad Dlim Massif of the Western Reguibat Shield contains several carbonatite complexes of previously unknown age. The largest and best studied are Gleibat Lafhouda, composed of magnesiocarbonatites, and Twihinate, composed of calciocarbonatites. Gleibat Lafhouda is hosted by Archean gneisses and schists. It has a SHRIMP U-Th-Pb zircon crystallization age of 1.85 ± 0.03 Ga, a Nd model age of TCR = 1.89 ± 0.03 Ga, and a Sm-Nd age of 1.85 ± 0.39 Ga. It forms part of the West Reguibat Alkaline province. Twihinate, on the other hand, is much younger. It is hosted by Late Silurian to Early Devonian deformed granites and has a zircon crystallization age of 104 ± 4 Ma, which is within error of the age of the carbonatites of the famous Richat Structure in the southwest Reguibat Shield. Like these, the Twihinate carbonatites are part of the Mid-Cretaceous Peri-Atlantic Alkaline Pulse. The Twihinate carbonatites contain abundant inherited zircons with ages that peak at ca. 420 Ma, 620 Ma, 2050 Ma, 2466 Ma, and 2830 Ma. This indicates that their substratum has West African rather than, as previously suggested, Avalonian affinities. It has, however, a Paleoproterozoic component that is not found in the neighboring western Reguibat Shield. The 421 Ma to 410 Ma gneissic granites hosting Twihinate are epidote + biotite + Ca-rich garnet deformed I-type to A-type granites derived from magmas of deep origin compatible, therefore, with being generated in a subduction environment. These granites form a body of unknown dimensions and petrogenesis, the study of which will be of key importance for understanding the geology and crustal architecture of this region.
DS201612-2283
2016
Bea, F.Cambeses, A., Garcia-Casco, A., Scarrow, J.H., Montero, P., Perez-Valera, L.A., Bea, F.Mineralogical evidence for lamproite magma mixing and storage at mantle depths: Socovos fault lamproites, SE Spain.Lithos, Vol. 266-267, pp. 182-201.Europe, SpainLamproite

Abstract: Detailed textural and mineral chemistry characterisation of lamproites from the Socovos fault zone, SE Spain Neogene Volcanic Province (NVP) combining X-ray element maps and LA-ICP-MS spot analyses has provided valuable information about mantle depth ultrapotassic magma mixing processes. Despite having similar whole-rock compositions, rocks emplaced in the Socovos fault are mineralogically varied: including type-A olivine-phlogopite lamproites; and type-B clinopyroxene-phlogopite lamproites. The Ol-lacking type-B predates Ol-bearing type-A by c. 2 million years. We propose that the mineralogical variations, which are representative of lamproites in the NVP as a whole, indicate mantle source heterogeneities. Major and trace element compositions of mineral phases suggest both metasomatised harzburgite and veined pyroxenite sources that were most likely closely spatially related. Thin section scale textural and compositional variations in mineral phases reveal heterogeneous mantle- and primitive magma-derived crystals. The variety of crystals points to interaction and mingling-mixing of ultrapotassic magma batches at mantle depths prior crustal emplacement. The mixing apparently occurred in a mantle melting zone with a channelised flow regime and localised magma chambers-reservoirs. Magma interaction was interrupted when the Socovos and other lithosphere-scale faults tore down to the mantle source region, triggering rapid ascent of the heterogeneous lamproite magma.
DS201703-0405
2017
Bea, F.Haissen, F., Cambeses, A., Montero, P., Bea, F., Dilek, Y., Mouttaqi, A.The Archean kaisilite nepheline syenites of the Awsard intrusive massif ( Reguibat Shield, West African craton, Morocco) and its relationship to alkaline magmatism of Africa.Journal of African Earth Sciences, Vol. 127, pp. 16-50.Africa, MoroccoCraton - magmatism
DS202001-0030
2019
Bea, F.Najih, A., Montero, P., Verati, C., Chabou, M.C., Fekkak, A., Baidder, L., Ezzouhairi, H., Bea, F., Michard, A.Initial Pangean rifting north of the West African craton: insights from late Permian U-Pb and 40Ar/39Ar dating of alkaline magmatism from the eastern Anti-Atlas ( Morocco).Journal of Geodynamics, Vol. 132, 17p.Africa, Moroccocamptonites

Abstract: Numerous mafic dykes, sills and laccoliths crop out in the southern part of the Tafilalt basin (Eastern Anti-Atlas, Morocco). These rocks intrude the mildly folded Ordovician to Early Carboniferous formations, consisting mainly of lamprophyric dolerites and camptonites with minor gabbros and syenodiorites. Previous geochemical studies have shown that the Tafilalt magmatism of sodic-alkaline affinity has been produced by low degrees of partial melting from an enriched deep mantle source within the garnet stability field. However, the age and the geodynamic context of these rocks were presently unknown since no isotopic dating had so far been made of the Tafilalt dolerites. To resolve this issue, we present here the first 40Ar/39Ar biotite and U-Pb zircon dating from the Tafilalt alkaline magmatism. Three samples (biotite separates) yielded well-defined 40Ar/39Ar plateau ages of 264.2?±?2.7 Ma, 259.0?±?6.3 Ma and 262.6?±?4.5 Ma whereas 206Pb/238U dating of zircon from one of these samples yielded an age of 255?±?3 Ma. These ages coincide within the dating error, and indicate that this magmatism occurred in the late Permian. Considering geochronological and geochemical data, we propose that the Tafilalt magmatism reflects an early-rift magmatic activity that preceded the Triassic rifting heralded by the Central Atlantic Magmatic Province. This magmatic activity is recorded in both sides of the future Atlantic Ocean by small-volume alkaline magmatism that started in the late Permian and extends into the Triassic. The alkaline magmas are probably generated in response to an increase in the mantle potential temperature underneath the Pangea supercontinent.
DS1987-0038
1987
Beach, R.D.W.Beach, R.D.W., Jones, F.W., Majorowicz, J.A.Heat flow and heat generation estimates for the Churchill basement of The western Canadian basin inAlberta, CanadaGeothermic, Vol. 16, No. 1, pp. 1-16AlbertaChurchill province, depth to basement, hot spots, Geothermometry
DS1993-1552
1993
Beakhouse, G.P.Sutcliffe, R.H., Barrie, C.T., Burrows, D.R., Beakhouse, G.P.Plutonism in the southern Abitibi Subprovince: a tectonics and petrogeneticframeworkEconomic Geology, Vol. 88, No. 6, September-October pp. 1359-1375Ontario, QuebecAbitibi Subprovince, Tectonics
DS200912-0039
2009
Beales, P.Beales, P.GOT kimberlite - NTGO is the custodian of a major kimberlite collection.37th. Annual Yellowknife Geoscience Forum, Abstracts p. 66-67.Canada, Northwest TerritoriesCore Library
DS2002-1731
2002
Bealieu, R.Witteman, J., Bealieu, R., Burlinggame, D., Hanks, C.The contribution of BHP Billiton's Ekati diamond mine to sustainable development in Canada's north.Australian Institute of Mining and Metallurgy, No. 3/2002, pp.179-84.Northwest TerritoriesMining - environmental agreement, socioeconomic, Deposit - Ekati
DS201809-1995
2018
Beall, A.P.Beall, A.P., Moresi, L., Cooper, C.M.Formation of cratonic lithosphere during the initiation of plate tectonics.Geology, Vol. 46, 6, pp. 487-490.Mantlecraton

Abstract: Earth’s oldest near-surface material, the cratonic crust, is typically underlain by thick lithosphere (>200 km) of Archean age. This cratonic lithosphere likely thickened in a high-compressional-stress environment, potentially linked to the onset of crustal shortening in the Neoarchean. Mantle convection in the hotter Archean Earth would have imparted relatively low stresses on the lithosphere, whether or not plate tectonics was operating, so a high stress signal from the early Earth is paradoxical. We propose that a rapid transition from heat pipe–mode convection to the onset of plate tectonics generated the high stresses required to thicken the cratonic lithosphere. Numerical calculations are used to demonstrate that an existing buoyant and strong layer, representing depleted continental lithosphere, can thicken and stabilize during a lid-breaking event. The peak compressional stress experienced by the lithosphere is 3×-4× higher than for the stagnant-lid or mobile-lid regimes immediately before and after. It is plausible that the cratonic lithosphere has not been subjected to this high stress state since, explaining its long-term stability. The lid-breaking thickening event reproduces features observed in typical Neoarchean cratons, such as lithospheric seismological reflectors and the formation of thrust faults. Paleoarchean "pre-tectonic" structures can also survive the lid-breaking event, acting as strong rafts that are assembled during the compressive event. Together, the results indicate that the signature of a catastrophic switch from a stagnant-lid Earth to the initiation of plate tectonics has been captured and preserved in the characteristics of cratonic crust and lithosphere.
DS1992-0100
1992
Beals, G.C.Beals, G.C.Sustainable development-the other side of the equationMinerals Industry International, No. 1006, May pp. 22-26GlobalEconomics, Sustainable development
DS1990-0179
1990
Beamish, D.Beamish, D.A granite window to the lower electrical crust and upper mantleTerra Nova, Vol. 2, pp. 314-319GlobalMantle, Geophysics -Magnetotellur
DS1975-0029
1975
Beams, S.Beams, S.Geology and Geochemistry of the Wyndham-whipstick Area, New south Wales.Canberra: Bsc. Thesis, Australia National University., AustraliaBasaltic Rocks
DS1993-1548
1993
Beane, R.Sturm, M., Smith, D.R., Beane, R., Wobus, .A.Geochemistry of late stage alkaline intrusions of the Pikes Peak Colorado.Geological Society of America Annual Abstract Volume, Vol. 25, No. 6, p. A261 abstract onlyColoradoAlkaline rocks, Geochemistry
DS1996-0834
1996
Beane, R.Lennykh, V.I., Valizer, P.M., Beane, R., et al.Petrotectonic evolution of the Maksyutov Complex, southern Urals, Russia:implications for metamorphismInternational Geology Review, Vol. 37, pp. 584-600.Russia, UralsPlate tectonics, Metamorphism -ultra high pressure
DS1996-0369
1996
Beane, R.J.Dobretsov, N.L., Shatsky, V.S., Beane, R.J.Tectonic setting and petrology of ultrahigh pressure metamorphic rocks In the Maksyutov Complex, Urals.International Geology Review, Vol. 38, No. 2, Feb. pp. 136-160.Russia, UralsPetrology, Tectonics
DS2003-0137
2003
Beane, R.J.Bostick, B.C., Jones, R.E., Ernst, W.G., Chen, C., Leech, M.L., Beane, R.J.Low temperature microdiamond aggregates in the Maksyutov metamorphic complexAmerican Mineralogist, Vol. 88, pp. 1709-17.Russia, UralsGeochemistry
DS200412-0185
2003
Beane, R.J.Bostick, B.C., Jones, R.E., Ernst, W.G., Chen, C., Leech, M.L., Beane, R.J.Low temperature microdiamond aggregates in the Maksyutov metamorphic complex, South Ural Mountains, Russia.American Mineralogist, Vol. 88, pp. 1709-17.Russia, UralsGeochemistry
DS200712-0058
2007
Beane, R.J.Beane, R.J., Sorensen, S.S.Protolith signatures and element mobility of the Maksyutov Complex subducted slab, Southern Ural Mountains, Russia.International Geology Review, Vol. 49, 1, pp. 52-72.Russia, UralsSubduction
DS2000-0070
2000
Beaney, C.L.Beaney, C.L., Shaw, J.The subglacial geomorphology of southeast Alberta: evidence for subglacialmelt water erosion.Canadian Journal of Earth Sciences, Vol. 37, No. 1, pp. 51-61.AlbertaGeomorphology - glacial
DS200512-0602
2004
Bear, S.Law, E., Bear, S., Van Horn, S.Petrographic evidence of an instant freeze of kimberlite diatreme.Geological Society of America Northeastern Meeting ABSTRACTS, Vol. 36, 2, p. 71.United States, PennsylvaniaTanoma kimberlite dykes, phreatomagmatism
DS1998-1007
1998
BeardMilledge, H.J., Woods, P.A., Beard, Shelkov, WillisCathodluminescence of polished carbonado7th International Kimberlite Conference Abstract, pp. 589-90.Brazil, Central African RepublicSpectroscopy, Microdiamonds - carbonado
DS1999-0691
1999
BeardSnyder, G.A., Taylor, Beard, Halliday, Sobolev, SimakovThe diamond bearing Mir eclogites: neodymium Strontium isotopic evidence for a possible early to Mid Proterozoic source7th International Kimberlite Conference Nixon, Vol. 2, pp. 808-15.Russia, Siberia, YakutiaDepleted mantle source with arc affinity, Mineral chemistry, geothermometry
DS2001-0692
2001
BeardLitvin, Yu.A., Jones, A.P., Beard, Divaev, ZharikovCrystallization of diamond and syngenetic minerals in melts of Diamondiferous carbonatites of Chagatai MassifDoklady, Vol.381A, No.9, Nov-Dec. pp. 1066-9.Russia, UzbekistanCarbonatite - diamond bearing, Deposit - Chagatai Massif
DS2002-0956
2002
BeardLitvin, Y.A., Jones, BeardCrystallization of diamond syngenetic minerals in melts of Diamondiferous carbonatites of Chagatai Massif 7.GPaDoklady, Vol. 381A, No. 9, pp. 1066-9.Russia, UzbekistanCarbonatite, Geochronology
DS1995-0933
1995
Beard, A.Kempton, P.D., Downes, H., Beard, A.Petrology and geochemistry of xenoliths from the northern Baltic shield:evidence for partial melting...Lithos, Vol. 36, No. 3/4, Dec. 1, pp. 157-184.Baltic Shield, Norway, Finland, KolaArchean Terrane, Metasomatism, Xenoliths
DS2003-1297
2003
Beard, A.Smith, C.B., Sims, K., Chimuka, L., Beard, A., Townend, R.Kimberlite metasomatism at Murowa and Sese pipes, Zimbabwe8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractZimbabweKimberlite geology and economics, Deposit - Murowa, Sese
DS200412-0476
2004
Beard, A.Downes, H., Beard, A., Hinton, R.Natural experimental charges: an ion microprobe study of trace element distribution coefficients in glass rich hornblendite andLithos, Vol. 75, 1-2, July, pp. 1-17.Europe, Germany, IsraelMagmatism, alkaline, igneous glasses, basanite. foidite
DS200512-0072
2004
Beard, A.Beard, A.A family of diamonds noted for their porous and black nature are found mainly in Brazil. Known as carbonados these diamonds are composed of microdiamonds and have experienced radioactive damage.Rough Diamond Review, No.7, December pp.South America, BrazilCarbonado, radioactive damage
DS200512-0247
2005
Beard, A.Downes, H., Balaganskaya, E., Beard, A., Liferovich, R., Demaiffe, D.Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola alkaline province: a review.Lithos, Advanced in press,Russia, Kola PeninsulaCarbonatite, kimberlites
DS200612-0348
2005
Beard, A.Downes, H., Balaganskaya, E., Beard, A., Liferovich, R., Demaiffe, D.Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola alkaline province: a review.Lithos, Vol. 85, 1-4, Nov-Dec. pp. 48-75.Russia, Kola PeninsulaCarbonatite
DS200912-0209
2009
Beard, A.Facer, J., Downes, H., Beard, A.In situ serpentinization and hydrous fluid metasomatism in spinel dunite xenoliths from the Bearpaw Mountains, Montana, USA.Journal of Petrology, Vol. 50, 8, pp. 1443-1475.United States, MontanaMetasomatism - not specific to diamonds
DS201012-0258
2010
Beard, A.Gwalani, L.G., Rogers, K.A., Demeny, A., Groves, D.L., Ramsay, R., Beard, A., Downes, P.J., Eves, A.The Yungul carbonatite dykes associated with the epithermal fluorite deposit at Speewah, Kimberley, Australia: carbon and oxygen isotope constraints originMineralogy and Petrology, Vol. 98, 1-4, pp. 123-141.AustraliaCarbonatite
DS201012-0533
2010
Beard, A.Nedli, Z., Toth, T.M., Downes, H., Csaszar, G., Beard, A., Szabo, C.Petrology and geodynamical interpretation of mantle xenoliths from Late Cretaceous lamprophyres Villany Mts. Hungary.Tectonophysics, Vol. 488, 1-4, pp. 43-54.Europe, HungaryLamprophyre
DS201212-0097
2012
Beard, A.Bulanova, G.P., Wiggers de Vries, D.F., Beard, A., Pearson, D.G., Mikhail, S.S., Smelov, A.P., Davies, G.R.Two stage origin of eclogitic diamonds recorded by a single crystal from the Mir pipe, Yakutia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Mir
DS201312-0840
2013
Beard, A.Smith, C.B., Haggerty, S.E., Chatterjee, B., Beard, A., Townend, R.Kimberlite, lamproite, ultramafic lamprophyre, and carbonatite relationships on the Dharwar Craton, India: an example from the Khaderpet pipe, a Diamondiferous ultramafic with associated carbonatite intrusion.Lithos, Vol. 182-183, pp. 102-113.IndiaDeposit - Khaderpet
DS201312-0841
2013
Beard, A.Smith, C.B., Haggerty, S.E., Chatterjee, B., Beard, A., Townend, R.Kimberlite, lamproite, ultramafic lamprophyre, carbonatite relationships on the Dharwar Craton, India; and example from the Khaderpet pipe, a Diamondiferous ultramafic with associated carbonatite intrusion.Lithos, Vol. 182-183, pp. 102-113.IndiaDeposit - Khaderpet
DS201412-0082
2014
Beard, A.Bulanova, G.P., Wiggers de Vries, D.F., Pearson, D.G., Beard, A., Mikhail, S., Smelov, A.P., Davies, G.R.An eclogitic diamond from Mir pipe (Yakutia), recording two growth events from different isotopic sources.Chemical Geology, Vol. 381, pp. 40-54.Russia, YakutiaDeposit - Mir
DS1996-0099
1996
Beard, A.D.Beard, A.D., Downes, H., Vetrin, V., Kempton, P.D.Petrogenesis of Devonian lamprophyre and carbonatite minor intrusions, Kandalaksha Gulf (Kola Peninsula).Lithos, Vol. 39, 1-2, Dec. pp. 93-119.RussiaCarbonatite, Kola Peninsula
DS1996-0100
1996
Beard, A.D.Beard, A.D., Downes, H., Vetrin, V., Kempton, P.D., MaduskiPetrogenesis of Devonian lamprophyre and carbonatite minor intrusions Kandalaksha Gulf, Kola Peninsula.Lithos, Vol. 39, pp. 93-119.Russia, Kola PeninsulaCarbonatite
DS1998-0093
1998
Beard, A.D.Beard, A.D., Downes, H., Hegner, E., Sablukov, S.M.Mineralogy and geochemistry of Devonian ultramafic minor intrusions of southern Kola Peninsula.Contributions to Mineralogy and Petrology, Vol. 130, pp. 288-303.Russia, Arkangelsk, Kola PeninsulaKimberlites, mellilites, Petrogenesis
DS1998-0094
1998
Beard, A.D.Beard, A.D., Mason, P.R.D., Downes, H.Depletion and enrichment processes in lithospheric mantle beneath the Baltic Shield (Kola and Arkangelsk)7th International Kimberlite Conference Abstract, pp. 58-60.Russia, Kola Peninsula, ArkangelskSpinel, garnet peridotites, Xenoliths
DS1998-0095
1998
Beard, A.D.Beard, A.D., Milledge, H.J.Infrared and microprobe studies of intrusions and micro-inclusions indiamond.7th International Kimberlite Conference Abstract, pp. 61-63.Australia, New South Wales, South Africa, ColoradoDiamond inclusions, Jagersfontein, George Creek, Carbonado - phosphate
DS2002-0400
2002
Beard, A.D.Downes, H., Kostoula, T., Jones, A.P., Beard, A.D., Thirwall, M.F., Bodinier, J.L.Geochemistry and Sr Nd isotopic compositions of mantle xenoliths from the MonteContributions to Mineralogy and Petrology, Vol. 144, 1, Oct. pp. 78-92.ItalyMelilite - carbonatite - not specific to diamonds
DS2003-0349
2003
Beard, A.D.Downes, H., Reichow, M.K., Mason, P.R.D., Beard, A.D., Thirlwall, M.F.Mantle domains in the lithosphere beneath the French Massif Central: trace element andChemical Geology, Vol. 200, 1-2, Oct. 16, pp. 71-87.Europe, FranceGeochronology, Peridotites
DS2003-0668
2003
Beard, A.D.Jones, A.P., Milledge, H.J., Beard, A.D.A new nitride mineral in carbonado8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractBrazilDiamonds - mineralogy
DS2003-0863
2003
Beard, A.D.Mahotkin, I.L., Downes, H., Hegner, E., Beard, A.D.Devonian dike swarms of alkaline, carbonatitic and primitiv magma type rocks from the8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractRussia, Kola PeninsulaMantle geochemistry
DS200412-0479
2003
Beard, A.D.Downes, H., Reichow, M.K., Mason, P.R.D., Beard, A.D., Thirlwall, M.F.Mantle domains in the lithosphere beneath the French Massif Central: trace element and isotopic evidence from mantle clinopyroxeChemical Geology, Vol. 200, 1-2, Oct. 16, pp. 71-87.Europe, FranceGeochronology, peridotites
DS200612-0103
2006
Beard, A.D.Beard, A.D., Downes, H., Mason, P.R.D., Vetrin, V.R.Depletion and enrichment processes in the lithospheric mantle beneath the Kola Peninsula (Russia): evidence from spinel lherzolite wehrlite xenoliths.Lithos, in pressRussia, Kola PeninsulaMetasomatism, Kandalaksha
DS200712-0059
2007
Beard, A.D.Beard, A.D., Downes, H., Mason, P.R., Vetrin, V.R.Depletion and enrichment processes in the lithospheric mantle beneath the Kola Peninsula ( Russia): evidence from spinel lherzolite and wehrlite xenoliths.Lithos, Vol. 94, 1-4, pp. 1-24.RussiaXenoliths
DS200712-1088
2007
Beard, A.D.Tomlinson, E.I., Beard, A.D., Harris, J.W.A snapshot of mantle metasomatism?Plates, Plumes, and Paradigms, 1p. abstract p. A1029.Canada, Northwest TerritoriesPanda
DS200812-0296
2007
Beard, A.D.Downes, H., Mahotkin, I.I., Beard, A.D., Hegner, E.Petrogenesis of alkali silicate, carbonatitic and kimberlitic magmas of the Kola alkaline carbonatite province.Vladykin Volume 2007, pp. 45-56.Russia, Kola PeninsulaCarbonatite
DS200912-0703
2009
Beard, A.D.Smith, C.B., Pearson, D.G., Bulanova, G.P., Beard, A.D., Carlson, R.W., Wittig, N., Sims, K., Chimuka, L., Muchemwa, E.Extremely depleted lithospheric mantle and diamonds beneath the southern Zimbabwe Craton.Lithos, In press available, 41p.Africa, ZimbabweDeposit - Murowa, Sese
DS201312-0062
2013
Beard, A.D.Beard, A.D., Howard, K., Carmody, L., Jones, A.P.The origin of melanophlogite, a clathrate mineral, in natrocarbonatite lava at Oldoinyo Lengai, Tanzania.American Mineralogist, Vol. 98, pp. 1998-2006.Africa, TanzaniaCarbonatite
DS201412-0577
2014
Beard, A.D.Mikhail, S., Guillermier, C., Franchi, I.A., Beard, A.D., Crispin, K., Verchovsky, A.B., Jones, A.P., Milledge, H.J.Empirical evidence for the fractionation of carbon isotopes between diamond and iron carbide from the Earth's mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, 4, pp. 855-866.MantleGeochronology
DS1997-1002
1997
Beard, B.Scherer, E.E., Cameron, K.L., Johnson, C.M., Beard, B.Lutetium - Hafnium geochronology applied to dating Cenozoic events affecting lower crustal xenoliths Kilbourne Hole.Chemical Geol., Vol. 142, No. 1-2, Oct. 20, pp. 63-78.New MexicoGeochronology, Kilbourne Hole
DS200812-0091
2008
Beard, B.Beard, B., Johnson, C., Bell, K.Iron isotope compositions of carbonatites record melt generation and late stage volatile loss processes.Goldschmidt Conference 2008, Abstract p.A62.MantleCarbonatite
DS1991-0087
1991
Beard, B.L.Beard, B.L., Medaris, L.G.Jr., Johnson, C.M.Diverse origins and ages of eclogite and garnet peridotite from the Bohemian Massif, CzechoslovakiaGeological Society of America Annual Meeting Abstract Volume, Vol. 23, No. 5, San Diego, p. A 46GlobalEclogite, Peridotite
DS1991-1115
1991
Beard, B.L.Medaris, L.G. Jr., Beard, B.L.Czech eclogites in the Moldanubian zone of the Bohemmian Massif:petrological characteristics and tectonic significanceGeological Society of America Annual Meeting Abstract Volume, Vol. 23, No. 5, San Diego, p. A 444GlobalEclogites, Petrology
DS1992-0101
1992
Beard, B.L.Beard, B.L., Johnson, C.L., Barovich, K.M.Hafnium isotopic composition of basaltic rocks from northwestern Colorado: evidence for changing source region mineralogy with timeEos, Transactions, Annual Fall Meeting Abstracts, Vol. 73, No. 43, October 27, abstracts p. 655ColoradoBasalts, Geochronology
DS1993-0091
1993
Beard, B.L.Beard, B.L.Extreme isotopic compositions of basanitic lavas from Deep Springs California: evidence for melting of mantle veinsGeological Society of America Annual Abstract Volume, Vol. 25, No. 6, p. A445 abstract onlyCaliforniaBasanite lavas
DS1993-0092
1993
Beard, B.L.Beard, B.L., Johnson, C.M.Hafnium isotope composition of late Cenozoic basaltic rocks from northwestern Colorado, United States (US): new constraints on mantle enrichment processes.Earth and Planetary Science Letters, Vol. 119, No. 4, October pp. 495-510.ColoradoGeochronology, Mantle enrichment
DS1993-0753
1993
Beard, B.L.Johnson, C.M., Beard, B.L.Evidence from hafnium isotopes for ancient sub-oceanic mantle beneath the Rio Grande riftNature, Vol. 362, No. 6419, April 1, pp. 441-443Colorado Plateau, New Mexico, ArizonaTectonics, Rio Grande Rift, Geochronology
DS1994-0121
1994
Beard, B.L.Beard, B.L.Strontium and neodymium isotopic composition of chromium diopside group mantle xenoliths from Tahiti, Society Islands.Eos, Vol. 75, No. 16, April 19, p. 191.GlobalXenoliths
DS1994-0122
1994
Beard, B.L.Beard, B.L.A geochemical study of eclogites from Mir and Udachnaya kimberlites, Russia reveals mantle heterogeneity.Eos, Annual Meeting November 1, Vol. 75, No. 44, p.710. abstractRussiaGeochemistry, Deposit -Mir, Udachnaya
DS1994-1420
1994
Beard, B.L.Qu Qi, Beard, B.L.Geochemistry and petrology of Al-augite group mantle xenoliths Tahiti, Society Islands.Eos, Vol. 75, No. 16, April 19, p. 191.GlobalXenoliths
DS1994-1421
1994
Beard, B.L.Qu Qi, Beard, B.L., Jin, Taylor, L.A.Petrology and geochemistry of aluminium augite and chromium diopside group mantle xenoliths from Tahiti, Society Islands.International Geology Review, Vol. 36, No. 2, February pp. 152-178.GlobalXenoliths, Petrology
DS1995-0123
1995
Beard, B.L.Beard, B.L., Snyder, G.A., Taylor, L.A., Fraracci, et al.Eclogites from the Mir kimberlite, Russia: evidence of an Archean ophioliteprotolith.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 41-43.Russia, Yakutia, Malo-BotubaEclogites, Deposit -Mir
DS1995-0124
1995
Beard, B.L.Beard, B.L., Taylor, L.A., Snyder, G.A.Compositional similarities between eclogites from different geologicsettings: Archean and Phanerozoic.Geological Society of America (GSA) abstract, Vol. 27, No. 2, March p. 36.GlobalEclogites
DS1995-1223
1995
Beard, B.L.Medaris, L.G., Beard, B.L., Johnson, O.H., Valley, J.M.Garnet pyroxenite and eclogite in the Bohemian Massif -geochemical evidence for Variscan recycling.Geologische Rundschau, Vol. 84, No. 3, Sept. pp. 489-505.GermanyEclogites, Subduction
DS1995-1790
1995
Beard, B.L.Snyder, G.A., Taylor, L.A., Beard, B.L., Sobolev, N.V.Siberian eclogite xenoliths: keys to differentiation of the Archeanmantle.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 549-551.Russia, YakutiaEclogite xenoliths, Deposit -Udachnaya. Mir
DS1996-0101
1996
Beard, B.L.Beard, B.L., Fracacci, K.N., Sobolev, N.V.Petrography and geochemistry of eclogites from the Mir kimberlite, Russia.Contributions to Mineralogy and Petrology, Vol. 125, No. 4, pp. 293-310.Russia, YakutiaGeochemistry, Deposit - Mir
DS1998-1367
1998
Beard, B.L.Snyder, G.A., Taylor, L.A., Beard, B.L., HallidayThe diamond bearing Mir eclogites, neodymium and Strontium isotopic evidence for continental crustal input Archean Oceanic7th International Kimberlite Conference Abstract, pp. 826-8.Russia, YakutiaEclogites, Deposit - Mir
DS1999-0049
1999
Beard, B.L.Beard, B.L., Glazner, A.F.Petrogenesis of isotopically unusual Pliocene olivine leucitites from Dee Springs Valley, California.Contributions to Mineralogy and Petrology, Vol. 133, pp. 402-417.CaliforniaMagma - potassic, Subduction
DS200612-0763
2005
Beard, B.L.Lapen, T.J., Medaris, L.G., Johnson, C.M., Beard, B.L.Archean to middle Proterozoic evolution of Baltica subcontinental lithosphere:Contributions to Mineralogy and Petrology, Vol. 150, 2, pp. 131-145.Europe, Baltic ShieldTectonics
DS200612-0902
2006
Beard, B.L.Medaris, L.G., Beard, B.L.Mantle derived UHP garnet pyroxenite and eclogite in the Moldanubian Gfohl Nappe, Bohemian Massif: a geochemical review, New PT and tectonic interpretationsInternational Geology Review, Vol. 48, 9, pp. 765-777.EuropeUHP
DS200812-0525
2008
Beard, B.L.Johnson, C.M., Beard, B.L., Roden, E.E.The iron isotope fingerprints of redox and biogeochemical cycling in modern and ancient Earth.Annual Review of Earth and Planetary Sciences, Vol. 36, May, pp. 457-493.MantleRedox
DS200912-0340
2009
Beard, B.L.Johnson, C.M., Bell, K., Beard, B.L., Shultis, A.J.Iron isotope compositions of carbonatites record melt generation, crystallization and late stage volatile transport processes.Mineralogy and Petrology, in press availableGlobalCarbonatite, geochronology
DS200912-0421
2009
Beard, B.L.Kylander Clar, A.R.C., Hacker, B.R., Johnson, C.M., Beard, B.L., Mahlen, N.Slow subduction of a thick ultrahigh pressure terrane.Tectonics, Vol. 28, 2, TC2003MantleUHP
DS201906-1273
2019
Beard, C.D.Beard, C.D., Goodenough, K.M., Deady, E.A.Deposit scale geomodels for REE and HFSE exploration in carbonatite and alkaline silicate magmatic systems.3rd International Critical Metals Meeting held Edinburgh, 1p.abstract p. 39.GlobalREE

Abstract: PDF link to presentation.
DS201909-2021
2019
Beard, C.D.Beard, C.D., Goodenough, K.M., Broom-Findlay, S., Borst, A.M., Roberts, N.M.W., Finch, A.A., Deady, E.A.Subducted sediments as a source of REE in mineralized post - collisional alkaline carbonatite systems.Goldschmidt2019, 1p. AbstractChinasubduction

Abstract: Many of the world's largest known REE deposits are associated with post-collisional alkaline-carbonatite magmatic complexes (e.g., the Minanning-Dechang belt, China). These systems are potassic to ultrapotassic in composition and contain LREE-dominated mineralisation associated with F and Ba-rich carbonatite breccias, carbonatite dykes and carbo-hydrothermal veins. They are typically emplaced through major shear zones during a period of 'relaxation' that postdates continental collision by up to 75 Ma. The subduction of sediment during continental collision is potentially a key control on the 'fertility' of the mantle source, and understanding the role of sediment is a crucial step towards better exploration models. However, the identification of sediment source components to alkaline systems has not been straightforward because their petrological complexity precludes traditional methods such as trace-element ratios and major-element modelling of crystal fractionation. We use a global database of Sr, Nd and Hf isotope compositions for alkaline and carbonatite systems, alongside geodynamic reconstructions to identify favourable source components for mineralisation and to provide direct information about the origin of the metals of interest. Subduction of shale and carbonate sequences is likely to introduce REE + HFSE and potentially mineralising ligands (F-, CO3 2-) into the mantle source for post-collisional alkaline systems; clastic sediments are poorer in these vital components. This research provides a framework through which the mineral exploration industry can identify tectonic environments that are predisposed to form REE mineralisation, providing regional-scale (100-1000 km) guidance especially for systems hidden beneath sedimentary cover.
DS202002-0163
2019
Beard, C.D.Beard, C.D., van Hinsberg, V.J., Stix, J., Wilke, M.Clinopyroxene melt trace element partitioning in sodic alkaline magmas.Journal of Petrology, in press available 92p. PdfEurope, Canary IslandsREE

Abstract: Clinopyroxene is a key fractionating phase in alkaline magmatic systems, but its impact on metal enrichment processes, and the formation of REE + HFSE mineralisation in particular, is not well understood. To constrain the control of clinopyroxene on REE + HFSE behaviour in sodic (per)alkaline magmas, a series of internally heated pressure vessel experiments was performed to determine clinopyroxene-melt element partitioning systematics. Synthetic tephriphonolite to phonolite compositions were run H2O-saturated at 200?MPa, 650-825?C with oxygen fugacity buffered to log f O2 ˜ ?QFM + 1 or log f O2 ˜ ?QFM +5. Clinopyroxene-glass pairs from basanitic to phonolitic fall deposits from Tenerife, Canary Islands, were also measured to complement our experimentally-derived data set. The REE partition coefficients are 0.3-53, typically 2-6, with minima for high-aegirine clinopyroxene. Diopside-rich clinopyroxenes (Aeg5-25) prefer the MREE and have high REE partition coefficients (DEuup to 53, DSmup to 47). As clinopyroxene becomes more Na- and less Ca-rich (Aeg25-50), REE incorporation becomes less favourable, and both the VIM1 and VIIIM2 sites expand (to 0.79 Å and 1.12 Å), increasing DLREE/DMREE. Above Aeg50 both M sites shrink slightly and HREE (VIri= 0.9 Å ˜ Y) partition strongly onto the VIM1 site, consistent with a reduced charge penalty for REE3+ ? Fe3+ substitution. Our data, complemented with an extensive literature database, constrain an empirical model that predicts trace element partition coefficients between clinopyroxene and silicate melt using only mineral major element compositions, temperature and pressure as input. The model is calibrated for use over a wide compositional range and can be used to interrogate clinopyroxene from a variety of natural systems to determine the trace element concentrations in their source melts, or to forward model the trace element evolution of tholeiitic mafic to evolved peralkaline magmatic systems.
DS1900-0240
1904
Beard, D.C.Beard, D.C.Diamond from Indiana. #1Letter To G.f. Kunz, Jan. 6TH.United States, Indiana, Great LakesDiamond Occurrence
DS1987-0039
1987
Beard, D.R.Beard, D.R.An optical study of defects in diamondPh.D. thesis, University of Reading, Berkshire, United Kingdom, 297pGlobalDiss. abstract BRDX81339, Diamond morphology
DS1989-0093
1989
Beard, J.S.Beard, J.S., Barker, F.Petrology and tectonic significance of gabbros,tonalites, and anorthosites in a late Paleozoic arc-root complex in the WrangelliaterraneJournal of Geology, Vol. 97, No. 6, November pp. 667-684AlaskaShoshonite, Tectonics
DS1989-0094
1989
Beard, J.S.Beard, J.S., Barker, F.Petrology and tectonic significance of gabbros,tonalites, shoshonites and anorthosites in a late Proterozoic arc-root complex in the Wrangella terraneJournal of Geology, Vol. 97, pp. 667-683AlaskaShoshonite, Tectonics
DS1993-0093
1993
Beard, J.S.Beard, J.S.Origin and emplacement of low K-silicic magmas in subduction settings. One page overview of Penrose Conference held Sept. 25-30, 1992Gsa Today, Vol. 3, No. 2, February pp. 38GlobalMagmas, Adakites
DS200512-0073
2005
Beard, J.S.Beard, J.S., Ragland, P.C.Reactive bulk assimilation: a model for crust mantle mixing in silicic magmas.Geology, Vol. 33, 8, August pp. 681-684.MantleMelting, geothermometry
DS1982-0091
1982
Beardsley, R.H.Beardsley, R.H.Modal Analysis of the Granite Mountain Pulaskite, Pulaski County, arkansaw.Msc. Thesis, University Arkansaw, 60P.United States, Gulf Coast, ArkansasSyenite, Petrology
DS1993-0094
1993
Beardsley, T.Beardsley, T.Trends in Russian Science: selling to surviveScientific American, Vol. 268, No. 2, Feb. pp. 92-100RussiaRussian Science, Marketing -strategies
DS201907-1550
2019
Beardsmore, T.Holden, E-J., Liu, W., Horrocks, T., Wang, R., Wedge, D., Duuring, P., Beardsmore, T.GeoDocA - fast analysis of geological content in mineral exploration reports: a text mining approach. Not specific to diamondOre Geology Reviews, in press available, 20p.AustraliaAnalysis system
DS1999-0050
1999
Beardsmore-Gray, T.Beardsmore-Gray, T.De Beers and today's diamond marketMan. Geological Survey Convention'99, p. 36. abstractManitobaNews item, Diamond markets
DS1996-0412
1996
Beate, B.Ego, F., Sebrier, M., Beate, B.Do the Billecocha normal faults reveal extension due to lithospheric body forces in the northern AndesTectonophysics, Vol. 265, No. 3/4, Nov. 30, pp. 255-274EcuadorTectonics, Faults
DS200612-1010
2006
Beaton, A.Olson, R., Eccles, D.R., Pana, D., Edwards, D., Beaton,A., Maslowski, A.Summary of mineral exploration during 2005, Diamondiferous kimberlites ( 2p.)Alberta Geological Survey, Jan. 20, 2p.Canada, AlbertaNews item - exploration activity
DS201012-0044
2010
Beatriz de Menezes Leal, A.Beatriz de Menezes Leal, A., Canabrava Brito, D., Girardi, V.A.V., Correa-Gomes, L.C., Cerqueira Cruz, S., Bastos Leal, L.R.Petrology and geochemistry of the tholeiitic mafic dykes from the Chapada Diamantina, northeastern Sao Francisco Craton, Brazil.International Dyke Conference Held Feb. 6, India, 1p. AbstractSouth America, BrazilGeochemistry
DS1993-0095
1993
Beattie, P.Beattie, P.Uranium-thorium disequilibration temperatures and partitioning on melting of garnetperidotiteNature, Vol. 363, No. 6424, May 6, pp. 63-65GlobalGeothermometry
DS1996-1158
1996
Beattie, P.D.Rao, C.N.V., Reed, S.J.B., Beattie, P.D.Larnitic kirschsteinite from the Kotakonda kimberlite, Andhra Pradesh, India.Mineralogical Magazine, Vol. 60, pt. 3, June 1, pp. 513-516.IndiaMineralogy, Deposit -Katakonda
DS1994-1037
1994
Beattie, R.Linton, T., Beattie, R., Brown, G.Presidium diamond factAustralian Gemologist, Vol. 18, No. 9, February pp. 279-281.GlobalHistory
DS1930-0101
1932
Beatty, C.Beatty, C.Conditions in the Diamond MarketMining Engineering Journal of South Africa, Vol. 42, PT. 2, Jan. 2ND. P. 455.South Africa, GlobalMining Economics
DS1996-0102
1996
Beatty, D.M.Beatty, D.M.Key criteria in successful mining equity financingSoutheast Asian Mining Conference, Sept. Toronto, 19p. slide diagrams no textGlobalEconomics, Financing -equity
DS1960-0529
1965
Beatty, L.B.Coleman, R.G., Lee, D.E., Beatty, L.B., Brannock, W.W.Eclogites and Eclogites -- their Differences and SimilaritieGeological Society of America (GSA) Bulletin., Vol. 76, No. 5, PP. 483-508.GlobalEclogites
DS2000-0347
2000
Beauchamp, W.Gomez, F., Beauchamp, W., Barazangi, M.Role of the Atlas Mountains (northwest Africa) within the African Eurasian plate boundary zone.Geology, Vol. 28, No. 9, Sept. pp. 775-8.Africa, North Africa, MoroccoTectonics
DS201012-0068
2010
BeaudoinBouabdellah, M., Hoernle,K., Kchit, A., Duggen, S., Hauff, Klugel, Lowry, BeaudoinPetrogenesis of the Eocene Tamzert continental carbonatites ( central High Atlas, Morocco): implications for a common source for Tamzert and CanaryJournal of Petrology, Vol. 51, 8, pp. 1655-1686.Europe, Canary Islands, MoroccoCarbonatite
DS2002-0568
2002
Beaudoin, G.Giguere, E., Corriveau, L., Beaudoin, G.Occurrence of ultramafic massifs in the western Grenville: petrogenesis and potential for diamond expl.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.39, p.39QuebecTemiscaming, Bryson intrusions
DS2002-0569
2002
Beaudoin, G.Giguere, E., Corriveau, L., Beaudoin, G.Occurrence of ultramafic massifs in the western Grenville: petrogenesis and potential for diamond expl.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.39, p.39QuebecTemiscaming, Bryson intrusions
DS201512-1963
2015
Beaudoin, G.Sappin, A-A., Beaudoin, G.Rare earth elements in Quebec, Canada: main deposit types and their economic potential.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 265-Canada, QuebecRare earths

Abstract: Rare earth elements (REE) are strategic metals vital to global economic growth because they are used in a wide range of high-technology industries (e.g., energy, transport, and telecommunications; Walters et al., 2011). The world production and reserves are mainly owned by China. In 2008, the Chinese government introduced export quotas on rare metals, which led to a global search for new sources of REE. Québec has substantial REE resources (Simandl et al., 2012), which may contribute to future production. Gosselin et al. (2003) and Boily and Gosselin (2004) inventoried rare metals (REE, Zr, Nb, Ta, Be, and Li) occurrences and deposits in Québec and, based mainly on lithological association, subdivided them into seven types: 1) deposits associated with peraluminous granitic complexes; 2) deposits associated with carbonatite complexes; 3) deposits associated with peralkaline complexes; 4) deposits associated with placers and paleoplacers; 5) iron oxide, Cu, REE, and U deposits; 6) deposits associated with granitic pegmatites, migmatites, and peraluminous to metaluminous granites; and 7) deposits associated with calc-silicate and metasomatized rocks or skarns. Herein we review REE mineralization in the province, adopting a more genetic scheme based on the classifi cation of Walters et al. (2011). The REE occurrences and deposits are subdivided into primary deposits, formed by magmatic and/ or hydrothermal processes, and secondary deposits, formed by sedimentary processes and leaching. Primary deposits are then subdivided into four types: 1) carbonatite complex-associated; 2) peralkaline igneous rock-associated; 3) REE-bearing Iron- Oxide-Copper-Gold (IOCG) deposits; and 4) hyperaluminous/ metaluminous granitic pegmatite-, granite-, and migmatiteassociated deposits, and skarns. Secondary deposits are subdivided into two deposit types: 1) placers and paleoplacers and 2) REE-bearing ion-adsorption clays.
DS201906-1271
2019
Beaudry, A.Barry, P.H., de Moor, J.M., Giovannelli, D., Schrenk, M., Hummer, D.R., Lopez, T., Pratt, C.A., Alpizar Segua, Y., Battaglia, A., Beaudry, A., Bini, G., Cascante, M., d'Errico, G., di Carlo, M., Fattorini, D., Fullerton, K., H+Gazel, E., Gonzalez, G., HalForearc carbon sink reduces long term volatile recycling into the mantle.Nature , 588, 7753, p. 487.Mantlecarbon

Abstract: Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth’s surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth’s deep mantle and shallow crustal reservoirs, as well as Earth’s oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent of carbon released from the slab and mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition. Around an additional three per cent is incorporated into the biomass through microbial chemolithoautotrophy, whereby microbes assimilate inorganic carbon into biomass. We estimate that between 1.2 × 108 and 1.3 × 1010 moles of carbon dioxide per year are released from the slab beneath the forearc, and thus up to about 19 per cent less carbon is being transferred into Earth’s deep mantle than previously estimated.
DS2000-0683
2000
BeaumierMoorhead, J., Perreault, S., Berclaz, Sharma, BeaumierKimberlites and diamonds in northern QuebecQuebec Department of Mines, Pro 99-09, 11p.Quebec, Ungava, LabradorExploration
DS1993-0096
1993
Beaumier, M.Beaumier, M., Dion, D-J., LaSalle, P., Moorhead, J.Exploration du diamant au Temiscamingue. (in French)Quebec Department of Mines Promotional, PRO 93-08, 7p.Quebec, TimiskamingGeochemistry, Heavy minerals-brief overview
DS1994-0123
1994
Beaumier, M.Beaumier, M., Lasalle, P., Warren, B., Lasalle, Y.R.Mineraux indicateurs de kimberlite dans les eskers du nord ouest Quebecois.(in French)Quebec Department of Mines, MB 93-60 1 map 1: 250, 000 paper copy $ 3.50QuebecGeochemistry, Mineralogy
DS1994-0124
1994
Beaumier, M.Beaumier, M., Rivard, P., Lefebrve, D.Contribution de la geochimie et geophysique a la recherche de diamants longdu rift lac Temiscamingue.Quebec Min. Mines, MB 94-63, 19p.QuebecGeochemistry, geophysics, Guigues kimberlite
DS1995-0125
1995
Beaumier, M.Beaumier, M.Geochimique des sediments de ruisseaux region de Belleterre Ville MarieQuebec Department of Mines, M.E.R., MB 91-28XQuebecGeochemistry
DS1995-0126
1995
Beaumier, M.Beaumier, M.Exploration geochimique au TemiscamingueQuebec Department of Mines, Pro 95-04QuebecGeochemistry
DS1999-0491
1999
Beaumier, M.Moorhead, J., Beaumier, M., Lefevbre, Bernier, MartelKimberlites, lineaments et rifts crustaux au Quebec #1Quebec Ministere des Ressources naturelles, (in French), MB99-35, approx. 60p.Quebec, Ungava, LabradorKimberlite, Tectonics, structure, fields, lineaments
DS2000-0681
2000
Beaumier, M.Moorhead, J., Beaumier, M.Distribution and characteristics of kimberlite fields in QuebecToronto Geological Discussion Group, absts Oct. 24, pp. 38-44.QuebecHistory, Diamond exploration
DS2000-0682
2000
Beaumier, M.Moorhead, J., Beaumier, M., Lefebvre, Bernier, MartelKimberlites, lineaments et rifts crustaux au Quebec #2Quebec Department of Mines, Report, 69p.QuebecKimberlites, tectonics, lineaments, rifts, Area - overviews
DS2001-0095
2001
Beaumier, M.Beaumier, M., Kirouac, F.Signal geochimique multi-element dans les sediments de ruisseaux dans le secteur de la kimberlite diamontifere de Guigues.Quebec Department of Mines, QuebecGeochemistry, Deposit - Guigues
DS2002-0126
2002
Beaumier, M.Beaumier, M.Les cibles d'exploration interessantes pour le diamant dans le district minier de la Cote Nord et du Moyen - Nord.Quebec dept. of Mines, 4p.Quebec, Cote Nord, Fermont, Haute Eastmain, RenardNews item, Geochemistry - indicator minerals
DS2002-0127
2002
Beaumier, M.Beaumier, M., Moorhead, J., Parent, M., Paradis, S.J.Synthese de l'activite d'exploration diamondifere au QuebecQuebec dept. of Mines, 2p.QuebecGeochemistry
DS2002-0128
2002
Beaumier, M.Beaumier, M., Parent, M., Paradis, S.Mineraux lourdes dans le till et ex pour le diamant, region du Lac Vernon (34J) terroire du Nouveau Quebec. M.I. Project de cartographie du Grand Nord.Quebec Ministere des Resources Naturelles, (FRE), MB2002-01.QuebecGeochemistry - heavy minerals
DS2002-1087
2002
Beaumier, M.Moorhead, J., Beaumier, M.L'exploration diamantifere au Quebec coup d'oeil sur la situationQuebec dept. of Mines, May 29, 2p.Quebec, Otish MountainsNews item, Brief - update on activity
DS2002-1088
2002
Beaumier, M.Moorhead, J., Beaumier, M.Ruee vers le diamant au Quebec - Otish, Wemindji, Alluviaq, Torngat, Temiscamingue, Desmaraisville, la Beaver, Renard, Nottaway, Caniapiscau, Bienville, AigneaultQuebec dept. of Mines, May 29, 6p.Quebec, Otish MountainsNews item, Brief - update on activity
DS2002-1214
2002
Beaumier, M.Parent, M., Beaumier, M., Paradis, S.A new high-potential target for diamond exploration in northern Quebec - Chromium picroilmenites in esker sediments of the Lac Bienville (33 P) regionUnknown, PRO 2002-03, 4 p.Quebecesker survey sample, microprobe analyses - chromium picroilmenites
DS2002-1215
2002
Beaumier, M.Parent, M., Beaumier, M., Paradis, S.J.A new high potential target for diamond exploration in northern Quebec: chromium picroilmenites in esker ..Quebec Department of Mines, PRO 2002-03, 4p.Quebec, Lac BienvilleGeochemistry - geomorphology
DS2003-0972
2003
Beaumier, M.Moorhead, J., Beaumier, M., Girard, R., Heaman, L.Distribution, structural controls and ages of kimberlite fields in the Superior Province of8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractQuebecGeochronology, tectonics
DS200412-1362
2003
Beaumier, M.Moorhead, J., Beaumier, M., Girard, R., Heaman, L.Distribution, structural controls and ages of kimberlite fields in the Superior Province of Quebec.8 IKC Program, Session 8, POSTER abstractCanada, QuebecDiamond exploration Geochronology, tectonics
DS200412-1499
2004
Beaumier, M.Parent, M., Beaumier, M., Girard, R., Paradis, S.J.Diamond exploration in the Archean craton of northern Quebec, kimberlite indicator minerals in eskers of the Saindon-Cambrien coQuebec Exploration Conference, MB 2004-02, 15p.Canada, QuebecOverview
DS2000-0443
2000
BeaumontJamieson, R.A., Beaumont, Vanderhaeghe, FullsackHow does the lower crust get hot?Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) 2000 Conference, 2p. abstract.MantleMagma - heat production
DS1984-0601
1984
Beaumont, C.Quinlan, G.M., Beaumont, C.Appalachian thrusting, lithospheric flexure, the Paleozoic of the eastern Interior of North America.Canadian Journal of Earth Sciences, Vol. 21, pp. 973-96.AppalachiaTectonics, Structure
DS1989-0169
1989
Beaumont, C.Braun, J., Beaumont, C.A physical explanation of the relation between flank uplifts and the breakup unconformity at rifted continental marginsGeology, Vol. 17, No. 8, August pp. 760-764GlobalTectonics, Rift
DS1989-0691
1989
Beaumont, C.Issler, D., McQueen, H., Beaumont, C.Thermal and isostatic consequences of simple shear extension of the continental lithosphereEarth and Planetary Science Letters, Vol. 91, pp. 341-358GlobalTectonics, Mantle
DS1989-1041
1989
Beaumont, C.Mitrovica, J.X., Beaumont, C., Jarvis, G.T.Tilting of continental interiors by the dynamical effects of subductionTectonics, Vol. 8, No. 5, October pp. 1079-1094MidcontinentTectonics, Structure
DS1990-0747
1990
Beaumont, C.Issler, D.R., Beaumont, C., Willett, S.D., Donelick, R.A., MooersPreliminary evidence from apatite fission track dat a concerning the thermal history of the Peace River Arch region, western Canada sedimentary basinGeology of the Peace River Arch, ed. Sc.C. O'Connell, J.S. Bell, Bulletin. Can., Vol. 38A, Special Volume, December pp. 260-269AlbertaGeochronology, Geothermometry
DS1994-0125
1994
Beaumont, C.Beaumont, C., Quinlan, G.A geodynamic framework for interpreting crustal scale seismic reflectivity patterns in compressional orogens.Geophysical Journal International, Vol. 116, pp. 754-783.MantleGeodynamics, Geophysics -seismics
DS1994-1918
1994
Beaumont, C.Willett, S.D., Beaumont, C.Subduction of Asian lithospheric mantle beneath Tibet inferred from models of continental collision.Nature, Vol. 369, No. 6482, June 23, pp. 642-644.ChinaMantle, Subduction
DS1995-0204
1995
Beaumont, C.Braun, J., Beaumont, C.Three dimensional numerical experiments of strain partitioning at oblique plate boundaries:Journal of Geophysical Research, Vol. 100, No. B9, pp. 18, 059-74.California, New ZealandTectonics
DS1999-0051
1999
Beaumont, C.Beaumont, C., Ellis, S., Pfiffner, A.Dynamics of sediment subduction accretion at convergent margins: short termmodes, long term deformation...Journal of Geophysical Research, Vol. 104, No. 8, Aug. 10, pp. 17, 573-602.MantleTectonics, Subduction
DS1999-0195
1999
Beaumont, C.Ellis, S., Beaumont, C., Pfiffner, O.A.Geodynamic models of crustal scale episodic tectonic accretion and underplating in subduction zones.Journal of Geophysical Research, Vol. 104, No. 7, July 10, pp. 15169-90.MantleGeophysics - seismics, Subduction
DS2000-0787
2000
Beaumont, C.Pysklywec, R.N., Beaumont, C., Fullsack, P.Modeling the behaviour of the continental mantle lithosphere during plate convergence.Geology, Vol. 28, No. 7, July, pp. 655-8.MantleSubduction, collision, modeling
DS2002-0763
2002
Beaumont, C.Jamieson, R.A., Beaumont, C., Nguyen, M.H., Lee, B.Interaction of metamorphism, deformation and exhumation in large convergent orogensJournal of Metamorphic Geology, Vol.20,1,pp. 9-24.GlobalOrogens - tectonics - not specific to diamonds
DS2003-1409
2003
Beaumont, C.Van der Hagaeghe, O., Medvedev, S., Fullsack, P., Beaumont, C., Jamieson, R.A.Evolution of orogenic wedges and continental plateaux: insights from crustalGeophysical Journal International, Vol. 153, 1, pp. 27-51.MantleGeothermometry, Subduction
DS200412-1603
2004
Beaumont, C.Pysklywec, R.N., Beaumont, C.Interplate tectonics: feedback between radioactive thermal weakening and crustal deformation driven by mantle lithosphere instabEarth and Planetary Science Letters, Vol. 221, 1-4, pp. 275-292.MantleGeothermometry
DS200412-2035
2003
Beaumont, C.Van der Hagaeghe, O., Medvedev, S., Fullsack, P., Beaumont, C., Jamieson, R.A.Evolution of orogenic wedges and continental plateaux: insights from crustal thermalmechanical models overlying subducting mantlGeophysical Journal International, Vol. 153,1, pp. 27-51.MantleGeothermometry Subduction
DS200612-0297
2006
Beaumont, C.Culshaw, N.G., Beaumont, C., Jamieson, R.A.The orogenic superstructure infrastructure concept: revisited, quantified, and revived.Geology, Vol. 34, 9, Sept. pp. 733-736.Canada, Ontario, Manitoba, Superior ProvinceTectonics, geophysics - seismics
DS200812-1242
2008
Beaumont, C.Warren, C.J., Beaumont, C., Jamieson, R.A.Modelling tectonic styles and ultra high pressure UHP rock exhumation during the transition from oceanic subduction to continental collision.Earth and Planetary Science Letters, Vol. 267, 1-2, pp.129-145.MantleSubduction
DS200812-1243
2008
Beaumont, C.Warren, C.J., Beaumont, C., Jamieson, R.A.Deep subduction and rapid exhumation: role of crustal strength and strain weakening in continental crust and ultrahigh pressure rock exhumation.Tectonics, Vol. 27, TC6002.MantleSubduction
DS200912-0040
2009
Beaumont, C.Beaumont, C., Jamieson, R.A., Butler, J.P., Warren, C.J.Crustal structure: a key constraint on the mechanism of ultra high pressure rock exhumation.Earth and Planetary Science Letters, Vol. 287, 1-2, pp. 116-129.MantleUHP
DS200912-0141
2009
Beaumont, C.Currie, C.A., Beaumont, C.Are diamond nearing Cretaceous kimberlites related to shallow angle subduction beneath western North America?GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyCanada, United StatesMagmatism
DS201012-0045
2010
Beaumont, C.Beaumont, C., Jamieson, R., Nguyen, M.Models of large, hot orogens containing a collage of reworked and accreted terranes.Canadian Journal of Earth Sciences, Vol. 47, 4, pp. 485-515.MantleCraton
DS201112-0229
2011
Beaumont, C.Currie, C.A., Beaumont, C.Are diamond bearing Cretaceous kimberlites related to low-angle subduction beneath western North America?Earth and Planetary Science Letters, Vol. 303, 1-2, pp. 59-70.United States, Wyoming, Colorado Plateau, Canada, Northwest TerritoriesSubduction - Laramide Orogeny
DS201212-0062
2012
Beaumont, C.Beaumont, C., Ings, S.J.Effect of depleted continental lithosphere counterflow and inherited crustal weakness on rifting of the continental lithosphere: general results.Journal of Geophysical Research, Vol. 117, B8, B08407MantleTectonics
DS201312-0435
2013
Beaumont, C.Jamieson, A., Beaumont, C.On the origin of orogens.Geological Society of America Bulletin, Vol. 125, pp. 1671-1702.TechnologyOrogen
DS201412-0423
2013
Beaumont, C.Jamieson, R.A., Beaumont, C.On the origin of orogens.Geological Society of America Bulletin, Vol. 125, pp. 1671-1702.TechnologyOrogen
DS201801-0080
2017
Beaumont, C.Wenker, S., Beaumont, C.Can metasomatic weakening result in the rifting of cratons?Tectonophysics, in press available, 19p.China, Canada, Africa, Tanzaniametasomatism

Abstract: Cratons are strong and their preservation demonstrates that they resist deformation and fragmentation. Yet several cratons are rifting now, or have rifted in the past. We suggest that cratons need to be weakened before they can rift. Specifically, metasomatism of the depleted dehydrated craton mantle lithosphere is a potential weakening mechanism. We use 2D numerical models to test the efficiency of simulated melt metasomatism and coeval rehydration to weaken craton mantle lithosphere roots. These processes effectively increase root density through a parameterized melt-peridotite reaction, and reduce root viscosity by increasing the temperature and rehydrating the cratonic mantle lithosphere. The models are designed to investigate when a craton is sufficiently weakened to undergo rifting and is no longer protected by adjacent standard Phanerozoic lithosphere. We find that cratons only become vulnerable to rifting following large-volume melt metasomatism (~ 30% by volume) and thinning of the gravitationally unstable cratonic lithosphere from > 250 km to ~ 100 km; at which point its residual crustal strength is important. Furthermore, our results indicate that rifting of cratons depends on the timing of extension with respect to metasomatism. An important effect in the large-volume melt models is the melt-induced increase in temperature which must have time to reach peak values in the uppermost mantle lithosphere before rifting. Release of water stored in the transition zone at the base of a big mantle wedge may provide a suitable natural setting for both rehydration and refertilization of an overlying craton and is consistent with evidence from the eastern North China Craton. An additional effect is that cratons subside isostatically to balance the increasing density of craton mantle lithosphere where it is moderately metasomatized. We suggest that this forms intracratonic basins and that their subsidence and subsequent uplift, and cratonic rifting constitute evidence of progressive metasomatism of cratonic mantle lithosphere.
DS201901-0088
2018
Beaumont, C.Wenker, S., Beaumont, C.Can metasomatic weakening result in the rifting of cratons?Tectonophysics, Vol. 746, pp. 3-21.Mantlegeodynamics

Abstract: Cratons are strong and their preservation demonstrates that they resist deformation and fragmentation. Yet several cratons are rifting now, or have rifted in the past. We suggest that cratons need to be weakened before they can rift. Specifically, metasomatism of the depleted dehydrated craton mantle lithosphere is a potential weakening mechanism. We use 2D numerical models to test the efficiency of simulated melt metasomatism and coeval rehydration to weaken craton mantle lithosphere roots. These processes effectively increase root density through a parameterized melt-peridotite reaction, and reduce root viscosity by increasing the temperature and rehydrating the cratonic mantle lithosphere. The models are designed to investigate when a craton is sufficiently weakened to undergo rifting and is no longer protected by adjacent standard Phanerozoic lithosphere. We find that cratons only become vulnerable to rifting following large-volume melt metasomatism (~ 30% by volume) and thinning of the gravitationally unstable cratonic lithosphere from > 250 km to ~ 100 km; at which point its residual crustal strength is important. Furthermore, our results indicate that rifting of cratons depends on the timing of extension with respect to metasomatism. An important effect in the large-volume melt models is the melt-induced increase in temperature which must have time to reach peak values in the uppermost mantle lithosphere before rifting. Release of water stored in the transition zone at the base of a big mantle wedge may provide a suitable natural setting for both rehydration and refertilization of an overlying craton and is consistent with evidence from the eastern North China Craton. An additional effect is that cratons subside isostatically to balance the increasing density of craton mantle lithosphere where it is moderately metasomatized. We suggest that this forms intracratonic basins and that their subsidence and subsequent uplift, and cratonic rifting constitute evidence of progressive metasomatism of cratonic mantle lithosphere.
DS201901-0089
2018
Beaumont, C.Wenker, S., Beaumont, C.Effects of lateral strength contrasts and inherited heterogeneities on necking and rifting of continents.Tectonophysics, Vol. 746, pp. 46-63.Mantlegeodynamics

Abstract: Besides the intrinsic rheological layering of the lithosphere and its thermal structure, inherited heterogeneities may play an important role in strain localization during continental extension. This is similar to the role that defects play in the failure and necking of other materials. Here, we consider both inherited small-scale weak zones and the effects of lateral juxtaposition of two lithospheres with differing properties as mechanisms to localize deformation and initiate necking instabilities. Using 2D finite-element models that contain lateral lithospheric boundaries, in combination with smaller scale heterogeneities, we illustrate that two controls determine how necking instabilities grow and thus lead to varying styles of rifting: Control 1, the stiff/pliable nature of the lithosphere and Control 2, the background strain rate in the lithosphere. Control 1 depends on the lithospheric rheology, such that necking instabilities grow faster in materials with high power-law creeping flow exponents (stiff, brittle lithosphere) than in those with low power-law creeping flow exponents (pliable, viscous lithosphere). Control 2 prevails in lithosphere where background strain rates are highest. This happens because necking amplifies the background strain rate in power-law materials, leading to faster necking where strain rates are highest. The model results show that Control 2 determines the location of localization, unless the background strain rate is equal or near equal in both lithospheres, in which case Control 1 wins. These results explain why rifting does not localize in cratons even though they contain heterogeneities. The results also provide a mechanism for the formation of asymmetric rifted margins.
DS1995-0158
1995
Beaumont-Smith, C.Bleeker, W., Beaumont-Smith, C.Thermal structural studies in Slave Province: preliminaryresults, implications Yellowknife domain.Geological Survey of Canada, Paper 1995-C, pp. 87-96.Northwest TerritoriesStructure, Yellowknife domain
DS201412-0146
2014
Beausir, B.Cordier, P., Demouchy, S., Beausir, B., Taupin, V., Barou, F., Fressengeas, C.Disinclinations provide the missing mechanism for deforming olivine-rich rocks in the mantle.Nature, Vol. 507, no. 7490, p. 51.MantleOlivine
DS1998-0526
1998
Beausoleil, C.Goutier, J., Doucet, P., Dion, C., Beausoleil, C.Geologie de la region du lac Esprit (SNRC 33F05)Quebec Department of Mines, RG 98-09, 39p.QuebecGeology
DS1998-0527
1998
Beausoleil, C.Goutier, J., Doucet, P., Dion, C., Beausoleil, C.Geologie de la region du lac Kowskatehkakmow (SNRC 33F06)Quebec Department of Mines, RG 98-16, 48p.QuebecGeology
DS201606-1100
2016
Beausoleil, Y.Kopylova, M.G., Beausoleil, Y., Goncharov, A., Burgess, J., Strand, P.Spatial distribution of eclogite in the Slave Craton mantle: the role of subduction.Tectonophysics, Vol. 672-673, pp. 87-103.Canada, Northwest TerritoriesSubduction

Abstract: We reconstructed the spatial distribution of eclogites in the cratonic mantle based on thermobarometry for ~ 240 xenoliths in 4 kimberlite pipes from different parts of the Slave craton (Canada). The accuracy of depth estimates is ensured by the use of a recently calibrated thermometer, projection of temperatures onto well-constrained local peridotitic geotherms, petrological screening for unrealistic temperature estimates, and internal consistency of all data. The depth estimates are based on new data on mineral chemistry and petrography of 148 eclogite xenoliths from the Jericho and Muskox kimberlites of the northern Slave craton and previously reported analyses of 95 eclogites from Diavik and Ekati kimberlites (Central Slave). The majority of Northern Slave eclogites of the crustal, subduction origin occurs at 110-170 km, shallower than in the majority of the Central Slave crustal eclogites (120-210 km). The identical geochronological history of these eclogite populations and the absence of steep suture boundaries between the central and northern Slave craton suggest the lateral continuity of the mantle layer relatively rich in eclogites. We explain the distribution of eclogites by partial preservation of an imbricated and plastically dispersed oceanic slab formed by easterly dipping Proterozoic subduction. The depths of eclogite localization do not correlate with geophysically mapped discontinuities. The base of the depleted lithosphere of the Slave craton constrained by thermobarometry of peridotite xenoliths coincides with the base of the thickened lithospheric slab, which supports contribution of the recycled oceanic lithosphere to formation of the cratonic root. Its architecture may have been protected by circum-cratonic subduction and shielding of the shallow Archean lithosphere from the destructive asthenospheric metasomatism.
DS201312-0504
2013
Beausoleil, Y.Y.L.Kopylova, M.M.G., Beausoleil, Y.Y.L.Distribution of eclogites in the Slave mantle: the effect of subduction and metasomatism.GAC-MAC 2013 SS4: from birth to the mantle emplacement in kimberlite., abstract onlyCanada, Northwest TerritoriesEclogite
DS201911-2510
2019
Beaussier, S.J.Beaussier, S.J., Gerya, T.V., Burg, J-P.3D numerical modelling of the Wilson cycle: structural inheritance of alternating subduction polarity.N: Cycle Concepts in Plate Tectonics, editors Wilson and Houseman , Geological Society of London special publication 470, 439-461.Mantleplate tectonics

Abstract: Alternating subduction polarity along suture zones has been documented in several orogenic systems. Yet the mechanisms leading to this geometric inversion and the subsequent interplay between the contra-dipping slabs have been little studied. To explore such mechanisms, 3D numerical modelling of the Wilson cycle was conducted from continental rifting, breakup and oceanic spreading to convergence and self-consistent subduction initiation. In the resulting models, near-ridge subduction initiating with the formation of contra-dipping slab segments is an intrinsically 3D process controlled by earlier convergence-induced ridge swelling. The width of the slab segments is delimited by transform faults inherited from the rifting and ocean floor spreading stages. The models show that the number of contra-dipping slab segments depends mainly on the size of the oceanic basin, the asymmetry of the ridge and variations in kinematic inversion from divergence to convergence. Convergence velocity has been identified as a second-order parameter. The geometry of the linking zone between contra-dipping slab segments varies between two end-members governed by the lateral coupling between the adjacent slab segments: (1) coupled slabs generate wide, arcuate linking zones holding two-sided subduction; and (2) decoupled slabs generate narrow transform fault zones against which one-sided, contra-dipping slabs abut.
DS1993-0097
1993
Beauvais, A.Beauvais, A., Colin, F.Formation and transformation processes of iron duricrust systems intropical humid environmentChemical Geology, Vol. 106, No. 1-2, May 5, pp. 77-102GlobalWeathering, Laterites
DS201312-0063
2013
Beaver, M.Beaver, M.Up close and personal - De Beers 125 years of unparalled success.Optima, Dec. pp. 7-9.GlobalHistory
DS200812-0092
2008
Beavers, B.Beavers, B.Aspects of garnet revealed at Sinkankas symposium. Two page overview of technical aspects.The Loupe, Vol. 17, 3, summer, p. 10-11.TechnologyGarnet - brief overview
DS1991-0088
1991
Beazley, J.S.Beazley, J.S.What is this thing called ethics and sometimes, the code of ethics?Photogrammetric Engineering and Remote Sensing, Vol. 57, No. 5, May pp. 497-499GlobalCode of ethics, Law
DS200512-0091
2005
Beblo, M.Bjornsson, A., Eysteinsson, H., Beblo, M.Crustal formation and magma genesis beneath Iceland: magnetotelluric constraints.Plates, Plumes, and Paradigms, pp. 665-686. ( total book 861p. $ 144.00)Europe, IcelandMagmatism
DS200612-0033
2006
Bebout, G.Arculus, R., Bebout, G.Fluid loss during early subduction.Goldschmidt Conference 16th. Annual, S6-01 theme abstract 1/8p. goldschmidt2006.orgMantleMetamorphism
DS1995-0127
1995
Bebout, G.E.Bebout, G.E.The impact of subduction zone metamorphism on mantle ocean chemicalcycling.Chemical Geology, Vol. 126, No. 2, Dec. 5, pp. 191-MantleGeochemistry, Subduction
DS1995-0128
1995
Bebout, G.E.Bebout, G.E.The impact of the subduction zone metamorphism on mantle ocean chemicalcyclingChemical Geology, Vol. 126, No. 2, Dec. 5, pp. 191-MantleGeochemistry, Subduction zone
DS1996-0103
1996
Bebout, G.E.Bebout, G.E., Scholl, D.W., Kirby, S.H., Platt, J.P.Subduction - top to bottoMAmerican Geophysical Union, Mon. 96, 384p. approx. $ 60.00GlobalBook - ad, Subduction
DS2002-0129
2002
Bebout, G.E.Bebout, G.E., Barton, M.D.Tectonic and metasomatic mixing in a high T subduction zone melange insights into the geochemical evolution of the slab mantle interface.Chemical Geology, Vol. 187,1-2,pp. 79-106.California, mantlePetrology - mineralogy, mixing mafics, ultramafics, Subduction zone
DS2002-0130
2002
Bebout, G.E.Bebout, G.E., Barton, M.D.Tectonic and metasomatic mixing in a high T subduction zone melange insights into the geochemical evolution of the slab mantle interface.Chemical Geology, Vol.187,No.1-2, pp.79-106.MantleTectonics, Subduction - metasomatism
DS2003-0088
2003
Bebout, G.E.Bebout, G.E., Nakamura, E.Record in metamorphic tourmalines of subduction zone devolatization and boronGeology, Vol. 31, 5, pp. 407-410.MantleSubduction, spectrometry, metamorphism
DS2003-0089
2003
Bebout, G.E.Bebout, G.E., Nakamura, E.Record in metamorphic tourmalines of subduction zone devolatization and boronGeology, Vol. 31, 5, May pp. 407-10.Mantle, CrustSpectrometry, metamorphism
DS200412-0116
2003
Bebout, G.E.Bebout, G.E., Nakamura, E.Record in metamorphic tourmalines of subduction zone devolatization and boron cycling.Geology, Vol. 31, 5, pp. 407-410.MantleSubduction, spectrometry, metamorphism
DS200512-0534
2004
Bebout, G.E.King, R.L., Bebout, G.E., Kobayashi, E., Van der Klauw, S.N.G.C.Ultrahigh pressure metabasaltic garnets as probes into deep subduction zone chemical weathering.Geochemistry, Geophysics, Geosystems: G3, Vol. 5, pp. Q12J14 10.1029/2004 GC000746MantleSubduction, eclogite
DS200512-0535
2005
Bebout, G.E.King, R.L., Bebout, G.E., Kobayashi, K., Nakamura, E., Van der Klauw, S.N.G.C.Ultrahigh pressure metabasaltic garnets as probes into deep subduction zone chemical cycling.Geochemistry, Geophysics, Geosystems: G3, Vol. 5, Q12J14, doi:10.1029/2004 GC000746TechnologyUHP
DS200612-0104
2006
Bebout, G.E.Bebout, G.E.Metamorphic chemical geodynamics of subduction zones.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.MantleSubduction
DS200612-0105
2006
Bebout, G.E.Bebout, G.E.Boron, lithium and nitrogen cycling through subduction zones.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.MantleSubduction
DS200612-0704
2006
Bebout, G.E.King, R.L., Bebout, G.E.Metamorphic evolution along the slab/mantle interface within subduction zones.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 17. abstract only.MantleMetamorphism
DS200712-0060
2007
Bebout, G.E.Bebout, G.E.Metamorphic chemical geodynamics of subduction zones.Earth and Planetary Science Letters, Vol. 260, 3-4, pp. 373-393.MantleUHP metamorphism
DS200812-0093
2008
Bebout, G.E.Bebout, G.E.Fate and geochemical imprint of deeply subducted sediments: evidence from HP/UHP metamorphic suites.Goldschmidt Conference 2008, Abstract p.A64.MantleSubduction
DS201012-0260
2010
Bebout, G.E.Halama, R., Bebout, G.E., John, T., Schenk, V.Nitrogen recycling in subducted oceanic lithosphere: the record in high and ultrahigh pressure metabasaltic rocks.Geochimica et Cosmochimica Acta, Vol. 74, 5, pp. 1636-1652.MantleUHP
DS201212-0280
2012
Bebout, G.E.Halama, R., Bebout, G.E., John, T., Scamberlluri, M.Nitrogen recycling in subducted mantle rocks and implications for the global nitrogen cycle.International Journal of Earth Sciences, in press available 19p.MantleSubduction
DS201312-0064
2013
Bebout, G.E.Bebout, G.E., Fogel, M.L., Cartigny, P.Nitrogen and its (biogeocosmo) chemical cycling: nitrogen: highly volatile yet surprisingly compatible.Elements, Vol. 9, pp. 333-338.TechnologyNitrogen
DS201312-0115
2013
Bebout, G.E.Busigny, V., Bebout, G.E.Nitrogen and its ( Biogeocosmo) chemical cycling: nitrogen in the silicate Earth: speciation and isotopic behavior during mineral-fluid interactions.Elements, Vol. 9, pp. 353-358.TechnologyNitrogen
DS202007-1127
2020
Bebout, G.E.Cannao, E., Tiepolo, M., Bebout, G.E., Scambelluri, M.Into the deep and beyond: carbon and nitrogen subduction recycling in secondary peridotites. Gagnone metaperidotitesEarth and Planetary Science Letters, Vol. 543, 116328 14p. PdfEurope, Switzerland, Alpsboron diamonds

Abstract: Understanding the volatile cycles at convergent margins is fundamental to unravel the Earth's evolution from primordial time to present. The assessment of fluid-mobile and incompatible element uptake in serpentinites via interaction with seawater and subduction-zone fluids is central to evaluate the global cycling of the above elements in the Earth's mantle. Here, we focus on the carbon (C), nitrogen (N) and C isotope compositions of chlorite harzburgites and garnet peridotites deriving from subduction-zone dehydration of former oceanic dehydration of serpentinite - i.e., metaperidotites (Cima di Gagnone, Swiss Central Alps) with the aim of evaluating the contribution of these rocks to the global C-N cycling. These ultramafic rocks, enclosed as lenses in a metasedimentary mélange, represent the destabilization of antigorite and chlorite at high-pressure/temperature (P/T) along a slab-mantle interface. Chlorite- and garnet-bearing rocks have similar ranges in C concentration ([C] = 210 - 2465 ppm and 304 - 659 ppm, respectively), with one magnesite-bearing chlorite harzburgite hosting 11000 ppm C. The average N concentrations ([N]) of the garnet peridotites (54 ± 15 ppm, one standard deviation indicated) are higher than those of the chlorite harzburgites (29 ± 6 ppm). The C of total C (TC) and total organic C (TOC) values of the Gagnone metaperidotites range from -12.2 to -17.8‰ and from -27.8 to -26.8‰, respectively, excluding the magnesite-bearing chlorite harzburgites with higher values of -7.2‰ (TC) and -21.2‰ (TOC). The [C] of these rocks are comparable to those of serpentinites form modern and ancient oceanic environments and with [C] of high-P serpentinites. However, the lack of preserved serpentinite precursors makes it difficult to determine whether release of H2O during high-P breakdown of antigorite and chlorite is coupled with significant C release to fluids. The C values appear to reflect mixing between seawater-derived carbonate and a reduced C source and a contribution from the host metasedimentary rocks ([C] = 301 ppm; [N] = 33 ppm; TC C = -24.4‰; TOC C = -27.0‰) cannot be completely excluded. The C-O isotope composition of the carbonate in magnesite-bearing chlorite harzburgites is compatible with progressive devolatilization at oxidized conditions, whereas the signatures of the majority of the other Gagnone samples appear to reflect different degree of interaction with sedimentary fluids. The [N] of the Gagnone metaperidotites are higher than those of oceanic and subducted serpentinites and show a range similar to that of high-P antigorite-serpentinites from mantle wedges. This enrichment is compatible with fluid-mediated chemical exchange with the surrounding metasedimentary rocks leading to strong modification of the Gagnone metaperidotites' geochemistry during prograde subduction along the slab-mantle interface. Comparing the C data reported in this study with published C values for diamonds, we suggest that the volatile recycling via Gagnone-like metaperidotites in subduction zones could contribute to deep-Earth diamond genesis and in particular to the formation of blue boron (B)-bearing diamonds. Our results highlight that the subduction of secondary peridotites evolved along the slab-mantle interface is a viable mechanism to inject volatiles into the deep mantle, particularly in hotter geothermal regimes such as the ones active during the early Earth's history.
DS202009-1615
2020
Bebout, G.E.Cannao, E., Scambelluri, M., Bebout, G.E., Agostini, S., Pettke, T., Godard, M., Crispini, L.Ophicarbonate evolution from seafloor to subduction and implications for deep-Earth C cycling.Chemical Geology, Vol. 546, 119626 29p. PdfMantlecarbon, subduction

Abstract: The chemical and physical processes operating during subduction-zone metamorphism can profoundly influence the cycling of elements on Earth. Deep-Earth carbon (C) cycling and mobility in subduction zones has been of particular recent interest to the scientific community. Here, we present textural and geochemical data (CO, Sr isotopes and bulk and in-situ trace element concentrations) for a suite of ophicarbonate rocks (carbonate-bearing serpentinites) metamorphosed over a range of peak pressure-temperature (P-T) conditions together representing a prograde subduction zone P-T path. These rocks, in order of increasing peak P-T conditions, are the Internal Liguride ophicarbonates (from the Bracco unit, N. Apennines), pumpellyite- and blueschist-facies ophicarbonates from the Sestri-Voltaggio zone (W. Ligurian Alps) and the Queyras (W. Alps), respectively, and eclogite-facies ophicarbonates from the Voltri Massif. The Bracco oceanic ophicarbonates retain breccia-like textures associated with their seafloor hydrothermal and sedimentary origins. Their trace element concentrations and d18OVSMOW (+15.6 to +18.2‰), d13CVPDB (+1.1 to +2.5‰) and their 87Sr/86Sr (0.7058 to 0.7068), appear to reflect equilibration during Jurassic seawater-rock interactions. Intense shear deformation characterizes the more deeply subducted ophicarbonates, in which prominent calcite recrystallization and carbonation of serpentinite clasts occurred. The isotopic compositions of the pumpellyite-facies ophicarbonates overlap those of their oceanic equivalents whereas the most deformed blueschist-facies sample shows enrichments in radiogenic Sr (87Sr/86Sr?=?0.7075) and depletion in 13C (with d13C as low as -2.0‰). These differing textural and geochemical features for the two suites reflect interaction with fluids in closed and open systems, respectively. The higher-P-metamorphosed ophicarbonates show strong shear textures, with coexisting antigorite and dolomite, carbonate veins crosscutting prograde antigorite foliation and, in some cases, relics of magnesite-nodules enclosed in the foliation. These rocks are characterized by lower d18O (+10.3 to 13.0‰), enrichment in radiogenic Sr (87Sr/86Sr up to 0.7096) and enrichment in incompatible and fluid-mobile element (FME; e.g., As, Sb, Pb). These data seemingly reflect interaction with externally-derived metamorphic fluids and the infiltrating fluids likely were derived from dehydrating serpentinites with hybrid serpentinite-sediment compositions. The interaction between these two lithologies could have occurred prior to or after dehydration of the serpentinites elsewhere. We suggest that decarbonation and dissolution/precipitation processes operating in ancient subduction zones, and resulting in the mobilization of C, are best traced by a combination of detailed field and petrographic observations, C, O and Sr isotope systematics (i.e., 3D isotopes), and FME inventories. Demonstration of such processes is key to advancing our understanding of the influence of subduction zone metamorphism on the mobilization of C in subducting reservoirs and the efficiency of delivery of this C to depths beneath volcanic arcs and into the deeper mantle.
DS201112-0088
2011
Beccaluca, L.Bianchini,G., Bryce, J.G., Blichert-Toft, J., Beccaluca, L., Natali, C.Pb Hf Nd isotopic decoupling in peridotite xenoliths from Mega ( Ethiopia): insights into multistage evolution of the East African lithosphere.Goldschmidt Conference 2011, abstract p.528.Africa, EthiopiaTanzanian Craton
DS201012-0046
2010
Beccaluv, P.L.Beccaluv, P.L.,et al.First evidence of lamprophyric magmatism within the subbetic zone southern Spain.Geologica Acta, Vol. 8, 2, pp.111-Europe, SpainMagmatism
DS1990-0180
1990
Beccaluva, L.Beccaluva, L., Coltori, M., Marchesi, S.Lithospheric oceanic mantle beneath the Canary Islands: evidence from ultramafic xenoliths from LanzaroteTerra, Abstracts of International Workshop Orogenic Lherzolites and Mantle Processes, Vol. 2, December abstracts p. 125GlobalBasanite, Alkaline rocks
DS1993-0277
1993
Beccaluva, L.Coltorti, M., Assimo, A., Beccaluva, L., et al.The Tchivra-Bonga alkaline carbonatite complex (Angola): petrology comparison with some Brazilian analogues.European Journal of Mineralogy, Vol. 5, No. 6, December pp. 1001-1024.Angola, BrazilCarbonatite
DS1994-0126
1994
Beccaluva, L.Beccaluva, L., Bonadiman, C.Metasomatic processes of upper mantle in different tectonic settings inferred from spinel perid. xenolithsInternational Symposium Upper Mantle, Aug. 14-19, 1994, pp. 111.GlobalMantle, Metasomatism
DS1998-0096
1998
Beccaluva, L.Beccaluva, L., Siena, Coltori, Di Grande, et al.Nephelinitic to tholeitic magma generation in a transtensional tectonicsetting: integrated model...Journal of Petrology, Vol. 39, No. 9, pp. 1547-76.ItalyIblean volcanism., Tectonics - magmatism
DS2000-0168
2000
Beccaluva, L.Coltorti, M., Beccaluva, L., Bonadiman, C.Glasses in mantle xenoliths as geochemical indicators of metasomatic agentsEarth and Planetary Science Letters, Vol.183, No.1-2, Nov.30, pp.303-20.GlobalXenoliths, glasses, Metasomatism
DS2001-0096
2001
Beccaluva, L.Beccaluva, L., Bianchini, G., Coltorti, Perkins, SienaMultistage evolution of the European lithospheric mantle: new evidence Sardinian peridotite xenolithsContributions to Mineralogy and Petrology, Vol. 142, No. 3, Dec. pp. 284-97.SardiniaXenoliths - petrology
DS2001-0097
2001
Beccaluva, L.Beccaluva, L., Blanchini, Coltori, Perkins, Siena, et al.Multistage evolution of the European lithospheric mantle: new evidence from Sardinian peridotite xenolithContribution Mineralogy Petrology, Vol. 142, No. 3, pp. 284-97.Sardinia, EuropePeridotite xenoliths
DS200412-0117
2004
Beccaluva, L.Beccaluva, L., Bianchini, G., Bonadiman, C., Siena, F., Vaccaro, C.Coexisting anorogenic and subduction related metasomatism in mantle xenoliths from the Betic Cordillera ( southern Spain). TallaLithos, Vol. 75, 1-2, July pp. 67-87.Europe, SpainSubduction, trace element fingerprinting, petrogenetic
DS200412-0348
2004
Beccaluva, L.Coltori, M., Beccaluva, L., Bonadiman, C., Faccini, B., Ntaflos, T., Siena, F.Amphibole genesis via metasomatic reaction with clinopyroxene in mantle xenoliths from Victoria Land, Antarctica. Mt. Melbourne,Lithos, Vol. 75, 1-2, July pp. 115-139.AntarcticaMetasomatism, trace element fingerprinting, glass
DS200612-0148
2005
Beccaluva, L.Bonadiman, C., Beccaluva, L., Coltort, M., Siena, F.Kimberlite like metasomatism and garnet signature in spinel peridotite xenoliths from Sal, Cape Verde Archipelago: relics of subcontinental mantle domain.Journal of Petrology, Vol. 46, 12, pp. 2465-2493.Europe, Cape Verde IslandsMetasomatism
DS200712-0061
2007
Beccaluva, L.Beccaluva, L., Azzouni Sekkal, A., Benhallou, A., Bianchini, G., Ellam, R.M., Marzola, M., Siena, StuartIntracratonic asthenosphere upwelling and lithosphere rejuvenation beneath the Hoggar swell (Algeria): evidence from HIMU metasomatized lherzolite mantle.Earth and Planetary Science Letters, Vol. 260, 3-4, pp. 482-494.Africa, AlgeriaMetasomatism
DS200812-0126
2008
Beccaluva, L.Bonadiman, C., Coltorti, M., Beccaluva, L., Siena, F.Mantle metasomatism vs host magma interaction: the ongoing controversy.Goldschmidt Conference 2008, Abstract p.A95.MantleMetasomatism
DS200912-0122
2009
Beccaluva, L.Coltorti, M., Downes, H., Gregoire, M., O'Reilly, S.Y., Beccaluva, L., Bonadiman, Piccardo.Rivalenti, SienaPetrological evolution of the European lithospheric mantle: from Archean to present day.Journal of Petrology, Vol. 50, no. 7, pp. 1181-1184.MantleMagmatism
DS201112-0075
2011
Beccaluva, L.Beccaluva, L., Bianchini, G., Wilson, M.Volcanism and Evolution of the African Lithosphere.GSA Special Paper 478, rock.geosociety.org /Bookstore, 331p. approx. $ 70.00AfricaBook - convection, mantle, rifts
DS201212-0510
2012
Beccaluva, L.Natali, C., Beccaluva, L., Bianchini, G., Ellam, R.M., Siea, F., Stuart, F.M.Carbonated alkali silicate metasomatism in the North Africa lithosphere: evidence from middle Atlas spinel lherzolites, Morocco.Journal of South American Earth Sciences, in press availableAfrica, MoroccoGeochemistry
DS201312-0065
2013
Beccaluva, L.Beccaluva, L.Mantle xenoliths from Bir Ali ( Yemen).Goldschmidt 2013, AbstractAfrica, YemenXenoliths
DS201312-0638
2013
Beccaluva, L.Natali, C., Beccaluva, L., Bianchini, G., Ellam, R.M., Siena, F., Stuart, F.M.Carbonated alkali silicate metasomatism in the North Africa lithosphere: evidence from Middle Atlas spinel lherzolites, Morocco.Journal of South American Earth Sciences, Vol. 41, pp. 113-121.Africa, MoroccoMetasomatism
DS201312-0800
2013
Beccaluva, L.Sgualdo, P., Beccaluva, L., Bianchini, G., Siena, F.Mantle xenoliths from Bir Ali ( Yemen).Goldschmidt 2013, 1p. AbstractAfrica, YemenXenoliths
DS201702-0194
2017
Beccaluva, L.Beccaluva, L., Bianchini, G., Natali, C., Siena, F.The alkaline carbonatite complex of Jacupiranga ( Brazil): magma genesis.Gondwana Research, Vol. 44, pp. 157-177.South America, BrazilCarbonatite

Abstract: A comprehensive study including new field, petrological and geochemical data is reported on the Jacupiranga alkaline-carbonatite complex (133-131 Ma) which, together with other alkaline complexes, occurs in southern Brazil and is coeval with the Paraná CFB province. It consists of a shallow intrusion (ca. 65 km2) in the Precambrian crystalline basement, and can be subdivided in two main diachronous plutonic bodies: an older dunite-gabbro-syenite in the NW and a younger clinopyroxenite-ijolite (s.l.) in the SE, later injected by a carbonatitic core (ca. 1 km2). An integrated petrogenetic model, based on bulk rock major and trace element analyses, mineral chemistry and Sr-Nd-Pb-C isotopic data, suggests that the two silicate intrusions generated from different mantle-derived magmas that evolved at shallow level (2-3 km depth) in two zoned cup-shaped plutonic bodies growing incrementally from independent feeding systems. The first intrusion was generated by OIB-like alkaline to mildly alkaline parental basalts that initially led to the formation of a dunitic adcumulate core, discontinuously surrounded by gabbroic cumulates, in turn injected by subanular syenite intrusive and phonolite dykes. Nephelinitic (± melilite) melts - likely generated deep in the lithosphere at = 3 GPa - were the parental magmas of the second intrusion and gave rise to large coarse-grained clinopyroxenite ad- to meso-cumulates, in turn surrounded, and partially cut, by semi-annular fine-layered melteigite-ijolite-urtite ortho-cumulates. The available isotopic data do not evidence genetic links between carbonatites and the associated silicate intrusions, thus favouring an independent source from the mantle. Moreover, it may be suggested that, unlike gabbro-syenites and carbonatites, mostly generated from lithospheric mantle sources, the parental magmas of the ijolite-clinopyroxenite intrusion also record the influence of sublithospheric (plume-related?) geochemical components.
DS201801-0042
2018
Beccaluva, L.Natali, C., Beccaluva, L., Bianchini, G., Siena, F.Coexistence of alkaline carbonatite complexes and high MgO CFB in the Parana-Etendeka province: insights on plume lithosphere interactions in the Gondwana realm.Lithos, Vol. 296-299, pp. 54-66.South America, Brazilcarbonatites
DS1991-1714
1991
Beccar, I.Thiele, R., Beccar, I., Levi, B., Nystrom, J.O., Vergara, M.Tertiary Andean volcanism in a caldera-graben settingGeologische Rundschau, Vol. 80, No. 1, pp. 179-186Andes, Chile, CordilleraStructure, Graben
DS1900-0241
1904
Beccari, O.Beccari, O.Wanderings in the Great Forests of Borneo; Travels and Researches of a Natura list in Sarawak.London: A. Constable And Co., 423P.Southeast Asia, BorneoTravelogue
DS2002-1025
2002
Beccero, A.I.McCammon, C.A., Beccero, A.I., Lauterbach, S., Blass, U., Marion, S.Oxygen vacancies in perovskite and related structures: implications for the lower mantle.Materials Research Society Symposium Proceedings, Vol. 718, pp. 109-114. Ingenta 1025440383MantlePerovskite
DS2000-0592
2000
Becchio, R.Lucassen, F., Becchio, R., Wemmer, K.Proterozoic Paleozoic development of the basement Andes ( 18 26 S) a mobile belt of the South American Craton.Journal of South American Earth Sciences, Vol. 13, No. 8, Aug.pp. 697-716.South America, AndesTectonics - not specific to diamonds
DS2002-0131
2002
Bechtel, A.Bechtel, A., Gratzer, R., Puttmann, W.,Oszczepalski, S.Geochemical characteristics across the oxic/anoxic interface Rote Faule front within the KuperschieferChemical Geology, Vol.185,1-2,pp.9-31.PolandGeochemistry, Deposit - Lubin Sieroszowice mining district
DS201809-2086
2018
Bechtel, H.Shim, S-H., Nisr, C., Chen, H., Leinenweber. K., Chizmeshya, A., Prakapenka, V., Kunz, M., Bechtel, H., Liu, Z.Hydrous silica in the lower mantle. BridgemaniteGoldschmidt Conference, 1p. AbstractMantlewater

Abstract: While mineral phases stable in the mantle transition zone (such as wadsleyite and ringwoodite) can store up to 3 wt% H2O, those in the lower mantle such as bridgmanite and ferropericlase can contain a very small amount (<50 ppm). While such dramatic differences can lead to dehydration/hydration and hydrous melting at 660-km depth in the mantle [1,2] it is uncertain how much water can be transported and stored at these depths. In order to answer this question, we have conducted a series of high pressure experiments in laser-heated diamondanvil cell and multi-anvil press combined with X-ray diffraction, infrared spectroscopy, laser Raman spectroscopy, and secondary ion mass spectrometry. Initially we examined the water storage capacity of dense (Al free) silica polymorphs at high pressure and temperature. We found that water can dramatically reduce the rutile-type to CaCl2-type phase transition from 55 GPa to 25 GPa and stabilize a new "disordered inverse" inverse NiAs-type phase at pressures above 50 GPa, which is not stable in dry SiO2 system. The CaCl2-type and NiAs-type silica polymorphs contain up to 8 wt% of H2O at 1400-2100 K up to at least 110 GPa. We next explored the effects of water on the mineralogy of the lower mantle and found that hydrous Mg2SiO4 ringwoodite (1 wt% H2O) breaks down to silica + bridgmanite + ferropericlase at pressures up to 60 GPa and 2100 K. The recovered silica samples contain 0.3-1.1 wt% H2O, suggesting that water stabilizes silica even under Si-undersaturated systems because of their large water storage capacity. Therefore, our observations support the stability of silica in hydrous regions in the pyrolitic lower mantle. In the subducting oceanic crust (basalt and sediment), silica represents 20-80% of the mineralogy. Because its stability range spans the mantle transition zone to the deep mantle, hydrous silica is expected to play a major role in the transport and storage of water in the deep mantle.
DS202010-1832
2020
Bechtel, H.A.Chen, H., Leinenweber, K., Prakapenka, V., Kunz, M., Bechtel, H.A., Liu, Z., Shim, S-H.Phase transformation of hydrous ringwoodite to the lower-mantle phases and the formation of hydrous silica.American Mineralogist, Vol. 105, pp. 1342-1348. pdfMantlebridgmanite

Abstract: To understand the effects of H2O on the mineral phases forming under the pressure-temperature conditions of the lower mantle, we have conducted laser-heated diamond-anvil cell experiments on hydrous ringwoodite (Mg2SiO4 with 1.1 wt% H2O) at pressures between 29 and 59 GPa and temperatures between 1200 and 2400 K. Our results show that hydrous ringwoodite (hRw) converts to crystalline dense hydrous silica, stishovite (Stv) or CaCl2-type SiO2 (mStv), containing 1 wt% H2O together with Brd and MgO at the pressure-temperature conditions expected for shallow lower-mantle depths between approximately 660 to 1600 km. Considering the lack of sign for melting in our experiments, our preferred interpretation of the observation is that Brd partially breaks down to dense hydrous silica and periclase (Pc), forming the phase assembly Brd + Pc + Stv. The results may provide an explanation for the enigmatic coexistence of Stv and Fp inclusions in lower-mantle diamonds.
DS1990-0181
1990
Bechtel, T.D.Bechtel, T.D., Forsyth, D.W., Sharpton, V.L., Grieve, R.A.F.Variations in effective elastic thickness of the NorthAmericanlithosphereNature, Vol. 343, No. 6259, February 15, pp. 636-638MidcontinentGeophysics, Bouguer gravity
DS1989-1124
1989
Beck, A.E.Nielsen, S.B., Beck, A.E.Heat flow density values and paleoclimate determined from stochastic inversion of four temperature-depthprofilesTectonophysics, Vol. 164, No. 2-4, August 1, pp. 345-360CanadaMantle, Crust -heat flow
DS1992-0102
1992
Beck, A.E.Beck, A.E.Inferring past climate change from subsurface temperature profiles: some problems and methodsPaleogeography, paleoclimatology, paleoecology, Vol. 98, No. 2-4, December pp. 73-80GlobalClimate, Paleoclimates
DS1995-1145
1995
Beck, J.N.Mahfoud, R.F., Beck, J.N.Composition, origin and classification of extrusive carbonatites in rift edSouthern Syria.International Geology Review, Vol. 37, No. 4, April pp. 361-?SyriaCarbonatite, Tectonics
DS1990-0238
1990
Beck, J.W.Brice, W.C., Lehmann, E.K., Beck, J.W., Knoll, A.Mining in Minnesota: balancing environmental protection and economicdevelopmentAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, No. 90-26, 10pMinnesotaLaw, Mining regulations
DS1859-0073
1842
Beck, L.C.Beck, L.C.Mineralogy of New YorkNatural History of New York, Mineralogy, PT. 3, P. 275.United States, Appalachia, New York, Finger LakesGeology
DS1994-0127
1994
Beck, M.E.Beck, M.E., Burmester, R.R., Drake, R.E., Riley, P.D.A tale of two continents: some tectonic contrasts between the Central Andes and the North America Cordillera as illustrated by their paleomagneticsignaturesTectonics, Vol. 13, No. 1, February pp. 215-Cordillera, Andes, ChileTectonics, Geophysics -paleomagnetics
DS1994-0128
1994
Beck, M.E.Beck, M.E., et al.A tale of two continents: some tectonic contrast between the central Andes and the North America Cordillera as illustrated by paleomagnetic signatures.Tectonics, Vol. 13, No.1, Feb. pp. 215-24.AndesTectonics, Geophysics - paleomagnetics - not specific to diamonds
DS1994-0129
1994
Beck, M.E.Beck, M.E., Russell, R., Burmester, et al.A tale of two continents: tectonic contrasts between the central Andes And the N. A. Cordillera, as illustrated by their paleomagnetic signatures.Tectonics, Vol. 13, No. 1, February pp. 215-Brazil, CaliforniaTectonics, Geophysics -paleomagnetics
DS200412-0118
2003
Beck, M.E.Beck, M.E., Housen, B.A.Absolute velocity of North America during the Mesozoic from paleomagnetic data.Tectonophysics, Vol. 377, 1, pp. 33-54.United States, CanadaGeophysics - paleomagetism
DS201605-0838
2016
Beck, M.L.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.
DS1996-0104
1996
Beck, P.Beck, P.Ground water and soil remediation techniquesGeoscience Canada, Vol. 23, No. 1, March pp. 22-40CanadaUrban areas - environment, Treatment technologies
DS1860-1017
1898
Beck, R.Beck, R.Die Diamantlagerstaette von Newland in Griqualand WestZeitschr. F. Prakt. Geol., Vol. 6, PP. 163-164.Africa, South Africa, Griqualand WestDiamond Occurrence
DS1860-1071
1899
Beck, R.Beck, R.Neues von den Afrikanischen Diamantlagerstaetten Newlands mineZeitschr. F. Prakt. Geol., Vol. 7, PP. 336-338. PP. 417-419.; ZEITSCHR. KRYST. (LEIPZIGAfrica, outh Africa, Cape ProvinceDiamond recovery
DS1900-0397
1906
Beck, R.Beck, R.Note on a Kyanite Bearing Rock from the Roberts Victor Diamond Mine.Geological Society of South Africa Proceedings, Vol. 9, P. XLVIII.Africa, South AfricaEclogite
DS1900-0532
1907
Beck, R.Beck, R.Untersuchungen Ueber Einige Sued afrikanische Diamantlagerstaetten.Zeitschr. Deut. Geol. Ges., Vol. 59, PP. 275-307.Africa, South AfricaGeology, Detailed, Petrography, Mineralogy
DS1991-0089
1991
Beck, R.D.Beck, R.D.The image of the mineralsJournal of Sth. Afr. Min. Metall, Vol. 91, No. 9, Sept. pp. 327-337South AfricaMining industry, Overview -image
DS1993-0429
1993
Beck, S.Fan, G.W., Wallace, T., Beck, S.Flexure of the Brazilian shield and possible implications for the deepstructure.American Geophysical Union, EOS, supplement Abstract Volume, October, Vol. 74, No. 43, October 26, abstract p. 548.BrazilTectonics, Structure
DS1998-1000
1998
Beck, S.Meyers, S.C., Beck, S., Wallace, T.Lithospheric scale structure across the Bolivian Andes from tomographic images of velocity and attentuation..Journal of Geophysical Research, Vol. 103, No. 9, Sept. 10, pp. 21, 233-52.Bolivia, AndesTomography, Tectonics
DS202007-1171
2020
Beck, S.Portner, D.E., Rodriguez, E.E., Beck, S., Zandt, G., Scire, A., Rocha, M.P.Detailed structure of the subducted Nazca slab into the lower mantle derived from continent scale teleseismic P wave tomography.Journal of Geophysical Research: Solid Earth, Vol. 125, e2019JB017884.Mantle, South Americasubduction

Abstract: Nazca subduction beneath South America is one of our best modern examples of long-lived ocean-continent subduction on the planet, serving as a foundation for our understanding of subduction processes. Within that framework, persistent heterogeneities at a range of scales in both the South America and Nazca plates is difficult to reconcile without detailed knowledge of the subducted Nazca slab structure. Here we use teleseismic travel time residuals from >1,000 broadband and short-period seismic stations across South America in a single tomographic inversion to produce the highest-resolution contiguous P wave tomography model of the subducting slab and surrounding mantle beneath South America to date. Our model reveals a continuous trench-parallel fast seismic velocity anomaly across the majority of South America that is consistent with the subducting Nazca slab. The imaged anomaly indicates a number of robust features of the subducted slab, including variable slab dip, extensive lower mantle penetration, slab stagnation in the lower mantle, and variable slab amplitude, that are incorporated into a new, comprehensive model of the geometry of the Nazca slab surface to ~1,100 km depth. Lower mantle slab penetration along the entire margin suggests that lower mantle slab anchoring is insufficient to explain along strike upper plate variability while slab stagnation in the lower mantle indicates that the 1,000 km discontinuity is dominant beneath South America.
DS1994-1978
1994
Beck, S.L.Zandt, G., Velasco, A.A., Beck, S.L.Composition and thickness of the southern Altiplano crust, BoliviaGeology, Vol. 221, No. 11, November pp. 1003-1006BoliviaTectonics, Cordilleran -Andes
DS1996-0105
1996
Beck, S.L.Beck, S.L., Zandt, G., et al.Crustal thickness variations in the central AndesGeology, Vol. 24, No. 5, May, pp. 407-410Bolivia, ArgentinaTectonics
DS2002-0132
2002
Beck, S.L.Beck, S.L., Zandt, G.The nature of orogenic crust in central AndesJournal of Geophysical Research, Oct. 29, 10.1029/2001JB000124.AndesOrogeny
DS200912-0802
2008
Beck, S.L.Wagner, L.B., Anderson, M.L., Jackson, J.M., Beck, S.L., Zandt,G.Seismic evidence for orthopyroxene enrichment in the continental lithosphere.Geology, Vol. 36, 12, Dec. pp. 936=938.MantleGeophysics - seismics
DS201601-0015
2015
Beck, S.L.Eakin, C.M., Long, M.D., Scire, A., Beck, S.L., Wagner, L.S., Zandt, G., Tavera, H.Internal deformation of the subducted Nazca slab inferred from seismic anisotropy. ..new study suggests that the Earth's rigid tectonic plates stay strong when they slide under another plate, known as subduction, may not be universal.Nature Geoscience, 10.1038/ngeo2592MantleSubduction
DS1990-0943
1990
Becker, A.Liu, Guimin, Becker, A.Evaluation of terrain effects in airborne electromagnetic surveysSociety of Exploration Geophysicists, 60th. Annual Meeting held, San, Vol. 1, pp. 700-703. Extended abstractGlobalGeophysics, electromagnetic -airborne
DS1992-0956
1992
Becker, A.Liu, G., Becker, A.Evaluation of terrain effects in AEM surveys using the boundary elementmethodGeophysics, Vol. 57, No. 2, February pp. 272-278GlobalGeophysics, AEM.
DS1993-0098
1993
Becker, A.Becker, A.Russian airborne geophysics and remote sensingThe Leading Edge, July pp. 784-785, 801RussiaGeophysics, Overview -brief
DS1993-1821
1993
Becker, A.Zhou, Q., Becker, A.Audio-frequency electromagnetic tomography in 2-DGeophysics, Vol. 58, No. 4, April pp. 482-495GlobalGeophysics, Tomography
DS1989-1502
1989
Becker, C.H.Tingle, T.N., Mathez, E.A., Becker, C.H.Constraints on the origin of organic compounds on crack surfaces in mantlexenolithsEos, Vol. 70, No. 43, October 24, p. 1411. AbstractNew MexicoSan Carlos, Xenoliths
DS1990-1467
1990
Becker, C.H.Tingle, T.N., Hochella, M.F., Becker, C.H.Reduced carbon in basalts and mantle xenolithsEos, Vol. 71, No. 17, April 24, p. 644 Abstract onlyGlobalBasalts, mantle xenoliths, Geochronology -carbon
DS1860-0970
1897
Becker, G.F.Becker, G.F.New Diamond Field in the Transvaal PremierScience., N.S. Vol. 6, No. 150, Nov. 12TH. PP. 664-667; PP. 726-727. AAfrica, outh Africa, TransvaalAlluvial placers
DS1992-0103
1992
Becker, H.Becker, H., Altherr, R.Evidence from ultra high pressure marbles for recycling of sediments into the mantleNature, Vol. 358, August 27, pp. 745-748AustriaMantle, Orogenic belts
DS1996-0106
1996
Becker, H.Becker, H.Crustal trace element and isotopic signatures in garnet pyroxenites from garnet peridotite Massifs from...Journal of Petrology, Vol. 37, No. 4, Aug. pp. 785-810.AustriaPeridotites, Geochemistry
DS1999-0052
1999
Becker, H.Becker, H., Jochum, K.P., Carlson, R.W.Constraints from high pressure veins in eclogites on the composition of hydrous fluids in subduction zones.Chemical Geology, Vol. 160, No. 4, Sept. 2, pp. 291-308.MantleEclogites
DS2000-0071
2000
Becker, H.Becker, H., Jochum, K.P., Carlson, R.W.Trace element fractionation during dehydration of eclogites from high pressure pressure terranes, element fluxesChemical Geology, Vol. 163, No. 1-4, pp. 65-99.Mantleultra high pressure (UHP), melting, Subduction zones
DS200612-0106
2006
Becker, H.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
DS200712-1107
2007
Becker, H.Van Acken, D., Becker, H., Wombacher, Walker, McDonough, Ash, PiccoliFractionated HSE in suboceanic mantle: assessing the influence of refertilization processes on upper mantle peridotites.Plates, Plumes, and Paradigms, 1p. abstract p. A1051.Europe, SwitzerlandWebsterite
DS200812-1198
2008
Becker, H.Van Acken, D., Becker, H., Walker, R.J.Refertilization of Jurassic oceanic peridotites from the Tethys Ocean: implications for the Re Os systematics of the upper mantle.Earth and Planetary Science Letters, Vol. 268, 1-2, pp. 171-181.MantlePeridotite
DS201212-0088
2012
Becker, H.Brey, G.P., Luchs, T., Shu, Q., Lazarov, M., Becker, H.Combined trace element, SM-ND, Luf-Hf and Re-Os studies constrain the age, origin and the development of the Kaapvaal subcratonic mantle.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, South AfricaGeochemistry
DS201805-0986
2018
Becker, H.van de Locht, J., Hoffmann, J.E., Li, C., Wang, Z., Becker, H., Rosing, M.T., Kleinschrodt, R., Munker, C.Earth's oldest mantle peridotites show entire record of late accretion.Geology, Vol. 46, 3, pp. 199-202.Europe, Greenlandperidotites

Abstract: An important issue in Earth’s earliest history is the timing and mixing history of the late accreted material that supplied highly siderophile elements to Earth’s mantle after core segregation. Previously, constraints on ancient mantle processes could only be obtained indirectly from mantle-derived magmas such as basalts or komatiites. Relics of Eoarchean (older than 3.8 Ga) mantle were proposed to occur within the Eoarchean terrains of western Greenland. Here we provide geochemical evidence, including combined platinum group element (PGE) and Re-Os isotope data, showing that modern mantle-like peridotites occur at two localities in southwest Greenland. Rhenium-depletion model ages of these peridotites are mostly of Eoarchean age, in accord with U-Pb zircon ages of crosscutting granitoid intrusives. PGE abundances and patterns are similar to those of modern depleted mantle peridotites. For the first time, such patterns provide conclusive evidence for preservation of Eoarchean depleted mantle rocks that are clearly distinguishable from magmatic cumulates or komatiites. Abundances of Os, Ir, and Ru combined with Os isotope compositions in the Greenland peridotites reveal that primitive late accreted material appears to have been efficiently mixed into the sampled mantle domains by Eoarchean time.
DS201908-1815
2019
Becker, H.Shu, Q, Brey, G.P., Pearson, G., Liu, J., Gibson, S.A., Becker, H.The evolution of the Kaapvaal craton: a multi-isotopic perspective from lithospheric peridotites from Finsch diamond mine.Precambrian Research, 105380, 21p. PdfAfrica, South Africadeposit - Finsch

Abstract: Accurately dating the formation and modification of Earth’s sub-cratonic mantle still faces many challenges, primarily due to the long and complex history of depletion and subsequent metasomatism of this reservoir. In an attempt to improve this, we carried out the first study on peridotites from the Kaapvaal craton (Finsch Mine) that integrates results from Re-Os, Lu-Hf, Sm-Nd and Sr-isotope systems together with analyses of major-, trace- and platinum-group elements. The Finsch peridotites are well-suited for such a study because certain compositional features reflect they were highly depleted residues of shallow melting (1.5?GPa) at ambient Archean mantle temperatures. Yet, many of them have overabundant orthopyroxene, garnet and clinopyroxene compared to expected modal amounts for residues from partial melting. Finsch peridotites exhibit a wide range of rhenium depletion ages (TRD) from present day to 2.7?Ga, with a prominent mode at 2.5?Ga. This age overlaps well with a Lu-Hf isochron of 2.64?Ga (eHf (t)?=?+26) which records silico-carbonatitic metasomatism of the refractory residues. This late Archean metasomatism is manifested by positive correlations of Pt/Ir and Pd/Ir with 187Os/188Os ratios and good correlations of modal amounts of silicates, especially garnet, with Os isotope ratios. These correlations suggest that the Highly Siderophile Elements (HSE) and incompatible element reenrichment and modal metasomatism result from one single major metasomatic event at late Archean. Our detailed study of Finsch peridotites highlights the importance of using multiple isotopic systems, to constrain the ages of events defining the evolution of lithospheric mantle. The Re-Os isotope system is very effective in documenting the presence of Archean lithosphere, but only the oldest TRD ages may accurately date or closely approach the age of the last major partial melting event. For a meaningful interpretation of the Re-Os isotope systematics the data must be combined with HSE patterns, trace-element compositions and ideally other isotopic systems, e.g. Lu-Hf. This is highlighted by the widespread evidence in Finsch peridotites of Pt, Pd and Re enrichment through significant Base Metal Sulfide (BMS) addition (mainly in the range of 0.002-0.08?wt%) that systematically shifts the mode of TRD model ages to younger ages.
DS2003-0343
2003
Becker, H.W.Dohmen, R., Chakraborty, S.,Becker, H.W.Si and O diffusion in olivine and implications for characterizing plastic flow in the mantleGeophysical Research Letters, Vol. 29, 21, Nov. 1, p. 26 DOI 10.1029/2002GLO15480MantleChemistry
DS2002-0478
2002
Becker, K.P.Franz, L., Becker, K.P., Kramer, W., Herzig, P.M.Metasomatic mantle xenoliths from the Bismarck microplate - thermal evolution, geochemistry...Journal of Petrology, Vol. 43, No. 2, pp. 315-44.Papua New GuineaSlab induced metasomatism - not specific to diamond, Xenoliths
DS1994-0130
1994
Becker, L.Becker, L., et al.Fullerenes in the 1.85 Billion year old Sudbury Impact StructureScience, Vol. 265, July 29, pp. 642-644OntarioSudbury Structure, Fullerenes
DS1996-0107
1996
Becker, L.Becker, L., Poreda, R.J., Bada, J.L.Extraterrestrial helium trapped in fullerenes in the Sudbury ImpactStructureScience, Vol. 272, April 12, pp. 249-252OntarioSIC, Impact crater
DS200612-0107
2006
Becker, M.Becker, M., Le Roex, A.P.Geochemistry of South African On and Off craton, Group I and Group II kimberlites: petrogenesis and source region evolution.Journal of Petrology, Vol. 47, 4, April pp. 673-703.Africa, South AfricaGenesis - craton
DS200812-0094
2007
Becker, M.Becker, M., Le Roex, A.P.Geochemistry and petrogenesis of South African transitional kimberlites located on and off the Kaapvaal Craton.South African Journal of Geology, Vol. 110, 4, pp. 631-646.Africa, South AfricaPetrogenesis of Group I and II
DS200812-0121
2008
Becker, S.Bodnar, R.J., Azbej, T., Becker, S., Cannatelli, C., Fall, A., Hole, J., Severs, M.The whole Earth geohydrologic cycle.Goldschmidt Conference 2008, Abstract p.A91.MantleWater
DS201112-0440
2011
Becker, S.Hofmann, M., Linnemann, U., Rai, V., Becker, S., Gartner, A., Sagawe, A.The India and South Chin a cratons at the margin of Rodinia - synchronous Neoproterozoic magmatism revealed by LA-ICP-MS zircon analyses.Lithos, In press available 65p.India, ChinaMagmatism
DS1990-0734
1990
Becker, S.D.Hutton, D.H.W., Dempster, T.J., Brown, P.E., Becker, S.D.A new mechanism of granite emplacement: intrusion in active extensional shear zonesNature, Vol. 343, February 1, pp. 452-455GlobalGranite, Shear zones
DS1999-0097
1999
Becker, S.M.Brown, P.E., Evans, I.B., Becker, S.M.Alkaline basaltic volcanism in the Tertiary of central East Greenland - the Trekantnunatakker.Transactions Royal Society. Edin. Earth Sci., Vol. 90, pp. 165-72.GreenlandPicrites, alkali basalts, Geochronology
DS200812-0095
2008
Becker, T.Becker, T., Kustowski, B., Ekstrom, G.Radial seismic anisotropy as a constraint for upper mantle rheology.Earth and Planetary Science Letters, Vol. 267, 1-2, pp.213-227.MantleGeophysics - seismics
DS1999-0053
1999
Becker, T.W.Becker, T.W., Faccena, C., Giardini, D.The development of slabs in the upper mantle: insights from numerical and laboratory experiments.Journal of Geophysical Research, Vol. 104, No. 7, July 10, pp. 15207-26.MantleExperimental, Subduction
DS200612-0108
2006
Becker, T.W.Becker, T.W., Chevrot, S., Schulte Pelkum, V., Blackman, D.K.Statistical properties of seismic anisotropy predicted by upper mantle geodynamic models.Journal of Geophysical Research, Vol. 111, B 18, B 8309.MantleGeophysics - seismics
DS200612-0109
2006
Becker, T.W.Becker, T.W., Chevrot, S., Schulte-Pelkum, V., Blackman, D.K.Statistical properties of seismic anisotropy predicted by upper mantle geodynamic models.Journal of Geophysical Research, Vol. 111, No. B8, B08309.MantleGeophysics - seismics
DS200612-0110
2006
Becker, T.W.Becker, T.W., Schulte-Pelkum, V., Blackman, D.K., Kellogg, J.B., O'Connell, R.J.Mantle flow under the western United States from shear wave splitting.Earth and Planetary Science Letters, in press availableUnited StatesGeophysics - seismics, tectonics, convection
DS200612-0111
2006
Becker, T.W.Becker, T.W., Sculte Pelkum, V., Blackman, D.K., Kellogg, J.B., O Connell, R.J.Mantle flow under the western United States from shear wave splitting.Earth and Planetary Science Letters, Vol. 247, 3-4, pp. 235-251.United StatesGeodynamics
DS200712-0062
2006
Becker, T.W.Becker, T.W.On the effect of temperature and strain rate dependent viscosity on global mantle flow, net rotation, and plate driving forces.Geophysical Journal International, Vol. 167, 2, Nov. 1, pp. 943-957.MantleGeothermometry
DS200712-0652
2007
Becker, T.W.Loyd, S.J., Becker, T.W., Conrad, C.P., Lithgow Bertonelli, C., Corsetti, F.A.Time variability in Cenozoic reconstructions of mantle heat flow: plate tectonic cycles and implications for Earth's thermal evolution.Proceedings of National Academy of Sciences USA, Vol. 104, 36, pp. 14266.MantleGeothermometry
DS200812-0128
2008
Becker, T.W.Bosch, L., Becker, T.W., Steinberger, B.On the statistical significance of correlations between synthetic mantle plumes and tomographic models.Physics of the Earth and Planetary Interiors, in press available, 9p.MantleDynamics, plumes, hot spots, tompography
DS200812-0373
2008
Becker, T.W.Funiciello, F., Faccenna, C., Heuret, A., Lallemand, S., Di Guiseppe, E., Becker, T.W.Trench migration, net rotation and slab mantle decoupling.Earth and Planetary Science Letters, Vol. 271, 1-4, pp. 233-240.MantleSubduction
DS200912-0605
2009
Becker, T.W.Qin, Y., Capdeville, Y., Montagner, J.P., Boschi, L., Becker, T.W.Reliability of mantle tomography models assessed by spectral element simulation.Geophysical Journal International, Vol. 177, 1, pp. 125-144.MantleTomography
DS201012-0190
2010
Becker, T.W.Faccenna, C., Becker, T.W., Lallemand, S., Lagabrielle, Y., Funiciello, F., Piromallo, C.Subduction triggered magmatic pulses: a new class of plumes?Earth and Planetary Science Letters, Vol. 299, 1-2, Oct. 15, pp. 54-68.MantleMagmatism
DS201012-0458
2010
Becker, T.W.Long, M.D., Becker, T.W.Mantle dynamics and seismic anisotropy.Earth and Planetary Science Letters, Vol. 297, 3-4, pp. 341-354.MantleGeodynamics
DS201212-0094
2012
Becker, T.W.Buffett, B.A., Becker, T.W.Bending stress and dissipation in subducted lithosphere.Journal of Geophysical Research, Vol. 117, B5, B05413MantleSubduction
DS201212-0473
2012
Becker, T.W.Miller, M.S., Becker, T.W.Mantle flow deflected by interactions between subducted slabs and cratonic keels.Nature Geoscience, Vol. 5, 10, pp. 726-730.MantleSubduction
DS201312-0256
2013
Becker, T.W.Faccenna, C., Becker, T.W., Conrad, C.P., Husson, L.Mountain building and mantle dynamics.Tectonics, Vol. 32, 1, pp. 80-93.MantleGeodynamics
DS201312-0257
2013
Becker, T.W.Faccenna, C., Becker, T.W., Jolivet, L., Keskin, M.Mantle convection in the Middle East: reconciling Afar upwelling, Arabia indentation and Aegean trench rollback.Earth and Planetary Science Letters, Vol. 375, pp. 254-269.Asia, ArabiaConvection
DS201312-0309
2013
Becker, T.W.Ghosh, A., Becker, T.W., Humphreys, E.D.Dynamics of the North American continent.Geophysical Journal International, Vol. 194, 2, pp. 651-669.United States, CanadaGeodynamics
DS201412-0779
2014
Becker, T.W.Schmandt, B., Jacobsen, S.D., Becker, T.W., Liu, Z., Dueker, K.G.Dehydration melting at the top of the lower mantle.Science, Vol. 344, 6189, June 13, pp. 1265-68.MantleWater in transition zone
DS201609-1745
2016
Becker, T.W.Steinberger, B., Becker, T.W.A comparison of lithospheric thickness models.Tectonophysics, in press available 14p.MantleCraton

Abstract: The outermost layer of the solid Earth consists of relatively rigid plates whose horizontal motions are well described by the rules of plate tectonics. Yet, the thickness of these plates is poorly constrained, with different methods giving widely discrepant results. Here a recently developed procedure to derive lithospheric thickness from seismic tomography with a simple thermal model is discussed. Thickness is calibrated such that the average as a function of seafloor age matches the theoretical curve for half-space cooling. Using several recent tomography models, predicted thickness agrees quite well with what is expected from half-space cooling in many oceanic areas younger than ˜ 110 Myr. Thickness increases less strongly with age for older oceanic lithosphere, and is quite variable on continents, with thick lithosphere up to ˜ 250 km inferred for many cratons. Results are highly correlated for recent shear-wave tomography models. Also, comparison to previous approaches based on tomography shows that results remain mostly similar in pattern, although somewhat more variable in the mean value and amount of variation. Global correlations with and between lithosphere thicknesses inferred from receiver functions or heat flow are much lower. However, results inferred from tomography and elastic thickness are correlated highly, giving additional confidence in these patterns of thickness variations, and implying that tomographically inferred thickness may correlate with depth-integrated strength. Thermal scaling from seismic velocities to temperatures yields radial profiles that agree with half-space cooling over large parts of their depth range, in particular for averaged profiles for given lithosphere thickness ranges. However, strong deviations from half-space cooling profiles are found in thick continental lithosphere above depth ˜ 150 km, most likely due to compositional differences.
DS201703-0409
2017
Becker, T.W.Jackson, M.G., Konter, J.G., Becker, T.W.Primordial helium entrained by the hottest mantle plumes.Nature Geoscience, Jan. 7, 1p. PreviewEurope, IcelandHot spots

Abstract: Helium isotopes provide an important tool for tracing early-Earth, primordial reservoirs that have survived in the planet’s interior1, 2, 3. Volcanic hotspot lavas, like those erupted at Hawaii and Iceland, can host rare, high 3He/4He isotopic ratios (up to 50 times4 the present atmospheric ratio, Ra) compared to the lower 3He/4He ratios identified in mid-ocean-ridge basalts that form by melting the upper mantle (about 8Ra; ref. 5). A long-standing hypothesis maintains that the high-3He/4He domain resides in the deep mantle6, 7, 8, beneath the upper mantle sampled by mid-ocean-ridge basalts, and that buoyantly upwelling plumes from the deep mantle transport high-3He/4He material to the shallow mantle beneath plume-fed hotspots. One problem with this hypothesis is that, while some hotspots have 3He/4He values ranging from low to high, other hotspots exhibit only low 3He/4He ratios. Here we show that, among hotspots suggested to overlie mantle plumes9, 10, those with the highest maximum 3He/4He ratios have high hotspot buoyancy fluxes and overlie regions with seismic low-velocity anomalies in the upper mantle11, unlike plume-fed hotspots with only low maximum 3He/4He ratios. We interpret the relationships between 3He/4He values, hotspot buoyancy flux, and upper-mantle shear wave velocity to mean that hot plumes—which exhibit seismic low-velocity anomalies at depths of 200 kilometres—are more buoyant and entrain both high-3He/4He and low-3He/4He material. In contrast, cooler, less buoyant plumes do not entrain this high-3He/4He material. This can be explained if the high-3He/4He domain is denser than low-3He/4He mantle components hosted in plumes, and if high-3He/4He material is entrained from the deep mantle only by the hottest, most buoyant plumes12. Such a dense, deep-mantle high-3He/4He domain could remain isolated from the convecting mantle13, 14, which may help to explain the preservation of early Hadean (>4.5 billion years ago) geochemical anomalies in lavas sampling this reservoir1, 2, 3.
DS201810-2295
2018
Becker, T.W.Behr, W.M., Becker, T.W.Sediment control on subduction plate speeds.Earth and Planetary Science Letters, Vol. 502, pp. 166-173.Indiasubduction

Abstract: Tectonic plate velocities predominantly result from a balance between the potential energy change of the subducting slab and viscous dissipation in the mantle, bending lithosphere, and slab-upper plate interface. A range of observations suggest that slabs may be weak, implying a more prominent role for plate interface dissipation than previously thought. The shallow thrust interface is commonly assumed to be weak due to an abundance of fluids and near-lithostatic pore fluid pressures, but little attention has been paid to the influence of the deeper, viscous interface. Here we show that the deep interface viscosity in subduction zones is strongly affected by the relative proportions of sedimentary to mafic rocks that are subducted to depth. Where sediments on the down-going plate are sparse, the deep interface is dominated by mafic lithologies that metamorphose to eclogites, which exhibit viscosities 1-2 orders of magnitude higher than the asthenospheric mantle, and reduce subduction plate speeds. In contrast, where sediments are abundant and subducted to depth, the deep interface viscosity is 1-2 orders of magnitude lower than the asthenospheric mantle, thus allowing significantly faster plate velocities. This correlation between subduction plate speed and deep sediment subduction may help explain dramatic accelerations (or decelerations) in convergence rates, such as the acceleration documented for India-Asia convergence during the mid-Cenozoic.
DS201901-0082
2018
Becker, T.W.Steinberger, B., Becker, T.W.A comparison of lithospheric thickness models.Tectonophysics, Vol. 746, pp. 325-238.Mantleplate tectonics

Abstract: The outermost layer of the solid Earth consists of relatively rigid plates whose horizontal motions are well described by the rules of plate tectonics. Yet, the thickness of these plates is poorly constrained, with different methods giving widely discrepant results. Here a recently developed procedure to derive lithospheric thickness from seismic tomography with a simple thermal model is discussed. Thickness is calibrated such that the average as a function of seafloor age matches the theoretical curve for half-space cooling. Using several recent tomography models, predicted thickness agrees quite well with what is expected from half-space cooling in many oceanic areas younger than ˜ 110 Myr. Thickness increases less strongly with age for older oceanic lithosphere, and is quite variable on continents, with thick lithosphere up to ˜ 250 km inferred for many cratons. Results are highly correlated for recent shear-wave tomography models. Also, comparison to previous approaches based on tomography shows that results remain mostly similar in pattern, although somewhat more variable in the mean value and amount of variation. Global correlations with and between lithosphere thicknesses inferred from receiver functions or heat flow are much lower. However, results inferred from tomography and elastic thickness are correlated highly, giving additional confidence in these patterns of thickness variations, and implying that tomographically inferred thickness may correlate with depth-integrated strength. Thermal scaling from seismic velocities to temperatures yields radial profiles that agree with half-space cooling over large parts of their depth range, in particular for averaged profiles for given lithosphere thickness ranges. However, strong deviations from half-space cooling profiles are found in thick continental lithosphere above depth ˜ 150 km, most likely due to compositional differences.
DS201905-1085
2019
Becker, T.W.Wang, W., Becker, T.W.Upper mantle seismic anisotropy as a constraint for mantle flow and continental dynamics of the North American plate.Earth and Planetary Science Letters, Vol. 514, 1, pp. 143-155.Mantlegeophysics - seismic

Abstract: The alignment of intrinsically anisotropic olivine crystals under convection is typically invoked as the cause of the bulk of seismic anisotropy inferred from shear-wave splitting (SWS). This provides a means of constraining the interplay between continental dynamics and the deep mantle, in particular for densely instrumented regions such as North America after USArray. There, a comparison of “fast orientations” from SWS with absolute plate motions (APM) suggests that anisotropy is mainly controlled by plate motions. However, large regional misfits and the limited realism of the APM model motivate us to further explore SWS based anisotropy. If SWS is estimated from olivine alignment in mantle circulation instead, plate-driven flow alone produces anisotropy that has large misfits with SWS. The addition of large-scale mantle density anomalies and lateral viscosity variations significantly improves models. Although a strong continental craton is essential, varying its geometry does, however, not improve the plate-scale misfit. Moreover, models based on higher resolution tomography degrade the fit, indicating issues with the flow model assumptions and/or a missing contributions to anisotropy. We thus compute a “lithospheric complement” to achieve a best-fit, joint representation of asthenospheric and frozen-in lithospheric anisotropy. The complement shows coherent structure and regional correlation with independently imaged crustal and upper mantle anisotropy. Dense SWS measurements therefore provide information on depth-dependent anisotropy with implications for tectonics, but much remains to be understood about continental anisotropy and its origin.
DS2002-1702
2002
Becker-Platen, J.D.Wellmer, F.W., Becker-Platen, J.D.Sustainable development and the exploitation of mineral and energy resources: a review.International Journal of Earth Sciences, Vol. 91, No. 5, Oct. pp. 723-45.GlobalEconomics - resources, mining industry guidelines
DS1960-0920
1968
Becket, J.B.Becket, J.B.Savage InterludeLondon: Hale., 189P., ILLUS.VenezuelaKimberlite, Kimberley, Janlib, Travelogue
DS200612-0112
2006
Becket, T.Becket, T., Schreiber, U., Kampunzu, A.B., Armstrong, R.Mesoproterozoic rocks of Namibia and their plate tectonic setting.Journal of African Earth Sciences, Vol. 46, 1-2, pp. 112-140.Africa, NamibiaTectonics
DS200412-0119
2004
Beckett, D.Beckett, D.Nervous genesis of a new Cullinan... beyond the stone's romance. Story mainly about the town.Optima, Vol. 50, 1, March pp. 47-57.Africa, South AfricaNews item - Cullinan ( the town)
DS1970-0504
1972
Beckett, J.Dolanski, J., Beckett, J.Heavy Mineral Identifications from Various Diamond Bearing Leads.New South Wales Geological Survey, GS 1972/14; GS 1972/211, (UNPUBL.).AustraliaKimberlite, Heavy Mineral Concentrates
DS1983-0127
1983
Beckett, J.R.Beckett, J.R., Tollo, R.P.A Revised Geothermometer for Coexisting Ilmenite and Clinopyroxene from Kimberlitic Nodule Suites.Geological Society of America (GSA), Vol. 15, No. 6, P. 524. (abstract.).GlobalGeothermometry, Genesis, Xenoliths
DS1992-0070
1992
Beckett, J.R.Baker, M.B., Newamn, S., Beckett, J.R., Stolper, E.M.Seperating liquid from crystals in high pressure melting experiments using diamond aggregatesGeological Society of America (GSA) Abstracts with programs, 1992 Annual, Vol. 24, No. 7, abstract p. A256New MexicoExperimental petrology, Diamond aggregates
DS1993-0099
1993
Beckett, J.R.Beckett, J.R., Stolper, E.M.The effects of crystal chemistry and melt composition on the partitioning of trace elements between melilite and meltEos, Transactions, American Geophysical Union, Vol. 74, No. 16, April 20, supplement abstract p. 343GlobalMineral chemistry
DS1999-0039
1999
Beckett, J.R.Baker, M.B., Beckett, J.R.The origin of abyssal peridotites: a reinterpretation of constraints Based on primary bulk compositions.Earth and Planetary Science Letters, Vol. 171, No. 1, Aug. 15, pp. 49-62.MantleGeochemistry - mineral chemistry, Peridotites
DS2000-0072
2000
Beckett, J.R.Beckett, J.R., Simon, S.B., Stolper, E.The partitioning of Sodium between melilite and liquid: pt. 2 Applications to Type B inclusions carb. chondritesGeochimica et Cosmochimica Acta, Vol. 64, No. 14, Jul. pp. 2519-34.GlobalPetrology - experimental, sodium, Melilite
DS2000-0073
2000
Beckett, J.R.Beckett, J.R., Stolper, E.The partioning of Sodium between melilite and liquid: pt. 1. the role of crystal chemistry and liquid composition.Geochimica et Cosmochimica Acta, Vol. 64, No. 14, Jul. pp. 2505-18.GlobalPetrology - experimental, Sodium, Melilite
DS2003-0710
2003
Beckett, J.R.Kessel, R., Beckett, J.R., Stolper, E.M.Experimental determination of the activity of chromite in multicomponent spinelsGeochimica et Cosmochimica Acta, Vol. 67, 16, pp. 3033-44.GlobalMineralogy - Chromite
DS200412-0990
2003
Beckett, J.R.Kessel, R., Beckett, J.R., Stolper, E.M.Experimental determination of the activity of chromite in multicomponent spinels.Geochimica et Cosmochimica Acta, Vol. 67, 16, pp. 3033-44.TechnologyMineralogy - Chromite
DS1990-0574
1990
Beckett, M.F.Gittins, J., Beckett, M.F., Jago, B.C.Composition of the fluid phase accompanying carbonatite magma: a criticalexaminationAmerican Mineralogist, Vol. 75, No. 9-10. Sept.-Oct. pp. 1106-1109QuebecOka, Husereau Hill, Carbonatite
DS1992-0576
1992
Beckett, M.F.Gittins, J., Beckett, M.F., Jago, B.C.Composition of the fluid phase accompanying carbonatite magmas: acritical examination- replyAmerican Mineralogist, Vol. 77, No. 5, 6, May-June pp. 666-667GlobalCarbonatite, Petrology
DS1991-0113
1991
Beckett, P.J.Beswick, A.E., Beckett, P.J., Courtin, G.M., Tapper, G.O.Evaluation of geobotanical remote sensing as an aid to mineral explorationin northeastern Ontario #2Ontario Geological Survey Open File, No. 5757, 22pOntarioGeobotany, Remote sensing
DS1983-0128
1983
Beckett, T.S.Beckett, T.S., Stockdale prospecting ltd.El 826 (part) El 828, El 829, El 830 (part) and El 837 Final Report March 1983.South Australia Geological Survey Open File., No. E 4993, 10P. 9 MAPS.Australia, South Australia, Barton, Coober PedyProspecting, Heavy Mineral Sampling
DS1983-0224
1983
Beckett, T.S.Fethers, G.H., Davies, P.R., Beckett, T.S., Stockdale ProspectingEl 955 Tarcoola Barton Progress Reports from 7/4/82 to 7/1/8South Australia Geological Survey Open File., No. E 4590, 9P. 2 MAPSAustralia, South AustraliaProspecting, Heavy Mineral Sampling
DS1980-0056
1980
Beckinsale, R.D.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
DS1990-1423
1990
Beckinsale, R.D.Strachan, R.A., Taylor, G.K., Beckinsale, R.D.Avalonian and Cadomian geology of the North AtlanticChapman and Hall, ?GlobalBook -ad, Baltic, North Atlantic -Avalonian
DS2002-0484
2002
BeckolmenFriberg, M., Juhlin, Beckolmen, Petrov, GreenPaleozoic tectonic evolution of the Middle Urals in the light of ESRU seismic experiment.Journal of the Geological Society of London, Vol.159,3,pp.295-306., Vol.159,3,pp.295-306.Russia, UralsTectonics
DS2002-0485
2002
BeckolmenFriberg, M., Juhlin, Beckolmen, Petrov, GreenPaleozoic tectonic evolution of the Middle Urals in the light of ESRU seismic experiment.Journal of the Geological Society of London, Vol.159,3,pp.295-306., Vol.159,3,pp.295-306.Russia, UralsTectonics
DS1987-0790
1987
BeckwithWhitten, T.E.H., Bornhorst, T.J., Gongshi Li, Hicks, D.L., BeckwithSuites, subdivision of batholiths and igneous rock classification:geological and mathematical conceptualizationAmerican Journal of Science, Vol. 287, April pp. 332-352GlobalClassification, Igneous rocks
DS1995-0129
1995
Becquer, T.Becquer, T., Bourdon, E., Petard, J.Disponibilite du nickel le long d'une toposequence de sols developpes surroches ultramafiques N. CaledoniaC.r. Academy Of Science Paris, Vol. 321, 11a, pp. 585-592New CaledoniaNickel, Ultramafics
DS1990-1364
1990
Bedard, D.Simpson, M.A., Millard, M.J., Bedard, D.Geological and remote sensing investigations of the Prince Albert-Shellbrook area, SaskatchewanSaskatchewan Research Council, Publishing No. R-1200-2-E-90, 30p. approx. $ 30.00SaskatchewanRemote sensing, Prince Albert area
DS1985-0052
1985
Bedard, J.Bedard, J., Ludden, J., Danis, D.Silica Over saturated Residua Derived by Fractionation Assimilation from a Camptonitic Parental Magma in the Megantic Complex.Geological Association of Canada (GAC)., Vol. 10, P. A 3, (abstract.).Canada, Quebec, Montregian HillsPetrography
DS1989-0296
1989
Bedard, J.Corriveau, L., Gold, D., Bedard, J., Bourne, J.Alkaline and calc-alkaline complexes of southern QuebecGeological Association of Canada (GAC) Field Trip, Trip No. B3, May 17-21, 129pQuebecKensington Pluton, Monteregian Hills, Saint Dorothea Roya, Mount Johnson, Mount Mega
DS201802-0221
2018
Bedard, J.Bedard, J.Stagnant lids and mantle overturns: implications for Archean tectonics, magmagenesis, crust growth, mantle evolution, and the start of plate tectonics.Geoscience Frontiers, Vol. 9, 1, pp. 19-49.Mantleplate tectonics

Abstract: The lower plate is the dominant agent in modern convergent margins characterized by active subduction, as negatively buoyant oceanic lithosphere sinks into the asthenosphere under its own weight. This is a strong plate-driving force because the slab-pull force is transmitted through the stiff sub-oceanic lithospheric mantle. As geological and geochemical data seem inconsistent with the existence of modern-style ridges and arcs in the Archaean, a periodically-destabilized stagnant-lid crust system is proposed instead. Stagnant-lid intervals may correspond to periods of layered mantle convection where efficient cooling was restricted to the upper mantle, perturbing Earth's heat generation/loss balance, eventually triggering mantle overturns. Archaean basalts were derived from fertile mantle in overturn upwelling zones (OUZOs), which were larger and longer-lived than post-Archaean plumes. Early cratons/continents probably formed above OUZOs as large volumes of basalt and komatiite were delivered for protracted periods, allowing basal crustal cannibalism, garnetiferous crustal restite delamination, and coupled development of continental crust and sub-continental lithospheric mantle. Periodic mixing and rehomogenization during overturns retarded development of isotopically depleted MORB (mid-ocean ridge basalt) mantle. Only after the start of true subduction did sequestration of subducted slabs at the core-mantle boundary lead to the development of the depleted MORB mantle source. During Archaean mantle overturns, pre-existing continents located above OUZOs would be strongly reworked; whereas OUZO-distal continents would drift in response to mantle currents. The leading edge of drifting Archaean continents would be convergent margins characterized by terrane accretion, imbrication, subcretion and anatexis of unsubductable oceanic lithosphere. As Earth cooled and the background oceanic lithosphere became denser and stiffer, there would be an increasing probability that oceanic crustal segments could founder in an organized way, producing a gradual evolution of pre-subduction convergent margins into modern-style active subduction systems around 2.5 Ga. Plate tectonics today is constituted of: (1) a continental drift system that started in the Early Archaean, driven by deep mantle currents pressing against the Archaean-age sub-continental lithospheric mantle keels that underlie Archaean cratons; (2) a subduction-driven system that started near the end of the Archaean.
DS1983-0129
1983
Bedard, J.H.Bedard, J.H.The Megantic Complex, a Member of the White Mountain Magma Series.Gems And Minerals, Vol. 64, No. 18, MAY 3RD. P. 337. (abstract.).United States, Appalachia, New York, VermontBlank
DS1984-0146
1984
Bedard, J.H.Bedard, J.H., Francis, HYNES, Nadeau.Fractionation in the Feeder System at a Proterozoic Rifted MarginCanadian Journal of Earth Sciences, Vol. 21, pp. 489-99.GlobalBasalts, Tectonics
DS1985-0053
1985
Bedard, J.H.Bedard, J.H.The opening of the Atlantic, the Mesozoic, New England igneous province and mechanisms of continental breakup.Tectonophysics, Vol. 113, pp. 209-232.Quebec, Ungava, LabradorTectonics, Gondwana
DS1988-0045
1988
Bedard, J.H.Bedard, J.H.Comparative amphibole chemistry of the Montregian and White Mountain alkaline suites and the origin of amphibole megacrysts in alkali basalts andlamprophyresMineralogical Magazine, Vol. 52, No. 364, No. 1, March pp. 91-104Quebec, VermontBlank
DS1992-0104
1992
Bedard, J.H.Bedard, J.H., Kerr, R.C., Hallworth, M.A.Porous sidewall and sloping flow crystallization experiments using a relative mush: implications for the self-channelization of residual melts incumulatesEarth and Planetary Science Letters, Vol. 111, No. 2/4, July pp. 319-330GlobalCrust, Layering, differentiation, cumulates
DS1994-0131
1994
Bedard, J.H.Bedard, J.H.Classification and evolution of Montregian lamprophyresGeological Society of America Abstracts, Vol. 26, No. 3, March, p. 6. AbstractQuebecLamprophyres
DS1994-0132
1994
Bedard, J.H.Bedard, J.H.Mesozoic east North American alkaline magmatism. 1. Evolution of Montregianlamprophyres, Quebec Canada.Geochimica et Cosmochimica Acta, Vol. 58, No.1, January pp. 459-470.QuebecLamprophyres, Alkaline magmatism
DS1996-0108
1996
Bedard, J.H.Bedard, J.H., LeCheminant, A.N.Alnoites and related rocks, Montregian Hills alkaline igneous province, Quebec.Geological Survey of Canada, LeCheminant ed, OF 3228, pp. 117-121.QuebecAlnoites, Montregian Hills
DS1996-0822
1996
Bedard, J.H.LeCheminant, A.N., Bedard, J.H.Diamonds associated with ultramafic complexes and derived placersGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 171-176.Cordillera, British Columbia, AppalachiaUltramafic complexes
DS1997-0084
1997
Bedard, J.H.Bedard, J.H.A new projection scheme and differentiation index for chromium-spinelsLithos, Vol. 42, No. 1-2, Dec. 1, pp. 37-46.GlobalMineralogy, classification, Spinels
DS2001-0098
2001
Bedard, J.H.Bedard, J.H.Parental magmas of the Nain plutonic suite anorthosites and mafic cumulates: a trace element modelling approachContributions to Mineralogy and Petrology, Vol. 141, No. 6, pp. 747-71.Quebec, Ungava, LabradorLayered intrusion, Anorthosite - mineralogy
DS2003-0090
2003
Bedard, J.H.Bedard, J.H.Evidence for regional scale pluton driven high grade metamorphism in the ArcheanJournal of Geology, Vol. 111, pp. 183-205.Quebec, Ungava, Douglas HarbourTectonics, lithotectonics, Metamorphism - not specific to diamonds
DS2003-0091
2003
Bedard, J.H.Bedard, J.H., Brouillette, P., Madorc, L., Berclaz, A.Archean cratonization and deformation in the northern Superior Province, Canada: anPrecambrian Research, Vol. 127, 1-2, Nov. pp. 61-87.Northwest Territories, QuebecTectonics
DS200412-0120
2003
Bedard, J.H.Bedard, J.H.Evidence for regional scale pluton driven high grade metamorphism in the Archean Minto Block, northern Superior Province, CanadaJournal of Geology, Vol. 111, pp. 183-205.Canada, Quebec, Labrador, UngavaTectonics, lithotectonics Metamorphism - not specific to diamonds
DS200412-0121
2003
Bedard, J.H.Bedard, J.H., Brouillette, P., Madorc, L., Berclaz, A.Archean cratonization and deformation in the northern Superior Province, Canada: an evaluation of plate tectonic versus verticalPrecambrian Research, Vol. 127, 1-2, Nov. pp. 61-87.Canada, Northwest Territories, QuebecTectonics
DS200612-0113
2006
Bedard, J.H.Bedard, J.H.A catalytic delamination driven model for coupled genesis of Archean crust and sub-continental lithospheric mantle.Geochimica et Cosmochimica Acta, Vol. 70, 5, pp. 1188-1214.MantleModel - delimination, melting, subduction, Minto Block
DS201312-0066
2013
Bedard, J.H.Bedard, J.H.How many arcs can dance on the head of a plume? A comment on: a critical assessment of Neoarchean 'plume only' geodynamics: evdience from the Superior province, by D. Wyman and his reply as well.Precambrian Research, Vol. 229, pp. 189-202.MantlePlate Tectonics
DS201412-0046
2014
Bedard, J.H.Bedard, J.H., Harris, L.B.Neoarchean disaggregation and reassembly of the Superior Craton.Geology, Vol. 42, 11, pp. 951-954.Canada, Ontario, QuebecCraton, geodynamics
DS201707-1306
2017
Bedard, J.H.Bedard, J.H.Stagnant lids and mantle overturns: implications for Archean tectonics, magmagenesis, crustal growth, mantle evolution, and the start of plate tectonics.Geoscience Frontiers, in press available 12p.Mantlesubduction

Abstract: The lower plate is the dominant agent in modern convergent margins characterized by active subduction, as negatively buoyant oceanic lithosphere sinks into the asthenosphere under its own weight. This is a strong plate-driving force because the slab-pull force is transmitted through the stiff sub-oceanic lithospheric mantle. As geological and geochemical data seem inconsistent with the existence of modern-style ridges and arcs in the Archaean, a periodically-destabilized stagnant-lid crust system is proposed instead. Stagnant-lid intervals may correspond to periods of layered mantle convection where efficient cooling was restricted to the upper mantle, perturbing Earth's heat generation/loss balance, eventually triggering mantle overturns. Archaean basalts were derived from fertile mantle in overturn upwelling zones (OUZOs), which were larger and longer-lived than post-Archaean plumes. Early cratons/continents probably formed above OUZOs as large volumes of basalt and komatiite were delivered for protracted periods, allowing basal crustal cannibalism, garnetiferous crustal restite delamination, and coupled development of continental crust and sub-continental lithospheric mantle. Periodic mixing and rehomogenization during overturns retarded development of isotopically depleted MORB (mid-ocean ridge basalt) mantle. Only after the start of true subduction did sequestration of subducted slabs at the core-mantle boundary lead to the development of the depleted MORB mantle source. During Archaean mantle overturns, pre-existing continents located above OUZOs would be strongly reworked; whereas OUZO-distal continents would drift in response to mantle currents. The leading edge of drifting Archaean continents would be convergent margins characterized by terrane accretion, imbrication, subcretion and anatexis of unsubductable oceanic lithosphere. As Earth cooled and the background oceanic lithosphere became denser and stiffer, there would be an increasing probability that oceanic crustal segments could founder in an organized way, producing a gradual evolution of pre-subduction convergent margins into modern-style active subduction systems around 2.5 Ga. Plate tectonics today is constituted of: (1) a continental drift system that started in the Early Archaean, driven by deep mantle currents pressing against the Archaean-age sub-continental lithospheric mantle keels that underlie Archaean cratons; (2) a subduction-driven system that started near the end of the Archaean.
DS202002-0202
2020
Bedard, J.H.Lawley, C.J.M., Pearson, G., Waterton, P., Zagorevski, A., Bedard, J.H., Jackson, S.E., Petts, D.C., Kjarsgaard, B.A., Zhang, S., Wright, D.Element and isotopic signature of re-fertilized mantle peridotite as determined by nanopower and olivine LA-ICPMS analyses.Chemical Geology, DOI:101016/ j.chemgeo.2020.119464Mantleperidotite

Abstract: The lithospheric mantle should be depleted in base- and precious-metals as these elements are transferred to the crust during partial melting. However, some melt-depleted mantle peridotites are enriched in these ore-forming elements. This may reflect re-fertilization of the mantle lithosphere and/or sequestering of these elements by residual mantle phase(s). Both processes remain poorly understood because of the low abundances of incompatible elements in peridotite and the nugget-like distribution of digestion-resistant mantle phases that pose analytical challenges for conventional geochemical methods. Herein we report new major and trace element concentrations for a suite of mantle peridotite and pyroxenite samples from the Late Permian to Middle Triassic Nahlin ophiolite (Cache Creek terrane, British Columbia, Canada) using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS) analysis of nanoparticulate powders and olivine. Compatible to moderately incompatible element concentrations suggest that Nahlin ophiolite peridotites represent residues after =20% melt extraction. Pyroxenite dykes and replacive dunite bands are folded and closely intercalated with residual harzburgite. These field relationships, coupled with the presence of intergranular base metal sulphide, clinopyroxene and Cr-spinel at the microscale, point to percolating melts that variably re-fertilized melt-depleted mantle peridotite. Radiogenic Pb (206Pb/204Pb?=?15.402-19.050; 207Pb/204Pb?=?15.127-15.633; 208Pb/204Pb?=?34.980-38.434; n?=?45) and Os (187Os/188Os 0.1143-0.5745; n?=?58) isotope compositions for a subset of melt-depleted peridotite samples further support metasomatic re-fertilization of these elements. Other ore-forming elements are also implicated in these metasomatic reactions because some melt-depleted peridotite samples are enriched relative to the primitive mantle, opposite to their expected behaviour during partial melting. New LA-ICPMS analysis of fresh olivine further demonstrates that a significant proportion of the highly incompatible element budget for the most melt-depleted rocks is either hosted by, and/or occurs as trapped inclusions within, the olivine-rich residues. Trapped phases from past melting and/or re-fertilization events are the preferred explanation for unradiogenic Pb isotope compositions and Paleozoic to Paleoproterozoic Re-depletion model ages, which predate the Nahlin ophiolite by over one billion years.
DS1987-0040
1987
Bedard, J.H.J.Bedard, J.H.J., Ludden, J.N., Francis, D.M.The Megantic intrusive complex, Quebec, a study of the derivation of silicaOver saturated anorogenic magmas of alkaline affinityJournal of Petrology, Vol. 28, No. 2, April pp. 355-388QuebecAlkaline rocks
DS1987-0041
1987
Bedard, J.H.J.Bedard, J.H.J., Ludden, J.N., Francis, D.M.The Megantic intrusive complex, Quebec-a study of the derivation of silicaOver saturated anorogenic magmas of alkaline affinityJournal of Petrology, Vol. 28, No. 2, April pp. 355-388QuebecBlank
DS1988-0046
1988
Bedard, J.H.J.Bedard, J.H.J., Francis, D.M., Ludden, J.Petrology and pyroxene chemistry of Montregian dykes-the origin of concentric zoning and green cores in clinopyroxenes from alkali basalts andlamprophyresCanadian Journal of Earth Sciences, Vol. 25, No. 12, December pp. 2041-2058QuebecPetrology, Montregian dykes
DS1989-0095
1989
Bedard, J.H.J.Bedard, J.H.J.Disequilibrium mantle meltingEarth and Planetary Science Letters, Vol. 91, pp. 359-366GlobalMantle genesis
DS1989-0096
1989
Bedard, J.H.J.Bedard, J.H.J.Alkaline magmatism. Special session Geol. Association Canada Annual MeetingG.a.c. Annual Meeting Scheduled May 15-17, 1989 In Montreal, Outline of session -briefQuebecAlkaline rocks
DS1989-0097
1989
Bedard, J.H.J.Bedard, J.H.J.Montregian alkaline lamprophyresGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A49. (abstract.)QuebecAlkaline rocks
DS1988-0047
1988
Bedard, L.P.Bedard, L.P.Petrography and geochemistry of the Dolodau stock;associated syenite andcarbonatite.(in French)Msc. Thesis University Of Du Quebec Chicoutimi, 186pQuebecDolodau stock, Carbonatite
DS1990-0182
1990
Bedard, L.P.Bedard, L.P.Petrogenesis of mantle derived large-ion lithophile elements (LILE) enriched Archean monzodiorites and Trachy andesites ( sanukitoids) ..Canadian Journal of Earth Sciences, Vol. 27, pp. 1135.OntarioSuperior Province, Alkaline rocks - calc alkaline
DS1991-0090
1991
Bedard, L.P.Bedard, L.P., Lapointe, B.Global warming: natural or anthropogenicGeoscience Canada, Vol. 18, No. 3, p. 98 onlyGlobalGlobal warming, Overview -climates
DS1992-0105
1992
Bedard, L.P.Bedard, L.P., Chown, E.H.The Dolodau dykes, Canada: an example of an Archean carbonatiteMineralogy and Petrology, Vol. 46, pp. 109-121QuebecCarbonatite, Dolodau dykes, petrography, geochemistry
DS201512-1979
2015
Bedard, L.P.Tremblay, J., Bedard, L.P., Matton, G.A petrographic study of Nb-bearing minerals at the Saint-Honore niobium deposit.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 75-82.Canada, QuebecNiobium

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

Abstract: The Saint-Honoré alkaline complex located near the Saguenay River (Grenville Province, Québec) has a syenite outer rim and concentric units of calcio-, magnesio- to ferro-carbonatite moving towards the centre. The Mg-carbonatite hosts a niobium deposit, and the Fe-carbonatite hosts a rare earth-rich zone at its centre. The Nb mineralization has a close spatial relationship to the syenite enclaves suggesting that the syenites may have played a critical role in concentrating the pyrochlore (Pcl). There are two forms of Nb mineralization: high- and low-grade. Low-grade mineralization is characterized by highly variable Pcl chemistry with higher U concentrations and a low abundance of fluoroapatite (Ap), whereas high-grade mineralization has a consistent Pcl chemistry (low-U), abundant Ap (with many acicular crystals) and more abundant phlogopite and magnetite. Some of the Pcl crystals have been altered to columbite by hydrothermal processes. It is interpreted that the metamict Pcl (rich in radioactive elements) was altered more readily than the Pcl having undamaged crystal structure. The high-grade mineralization is generally located near the syenite enclaves. Syenite enclaves (from a centimetre scale to several tens of metres in size) reacted with the carbonatite magma to produce a phlogopite rim. Ap is also abundant along the immediate contact between the enclaves and Mg-carbonatite. Large enclaves show hydro-fracturing by the carbonatite suggesting they were crystalline enough to be brittle. There are smaller textures (3-6 mm in diameter) that share many similarities with the syenite enclaves; however, these textures are rounded and could be interpreted as being related to liquid immiscibility. The interaction of carbonatite magma with syenite enclaves is interpreted to have started with abundant crystallization of acicular Ap which depleted the magma in F and lowered the magma's Nb-solubility. Pcl then crystallized in abundance in the vicinity of the syenite enclaves to create the economic Nb-rich zone.
DS201906-1301
2019
Bedard, L.P.Higgins, M., Bedard, L.P., dos Santos, E., Vander Auwera, J.Lamprophyres, carbonatites and phoscorites of the Saguenay City alkali province, Quebec, CanadaGAC/MAC annual Meeting, 1p. Abstract p. 108.Canada, QuebecCcrbonatite

Abstract: The Saguenay City alkali province (~ 580 Ma) comprises the Saint-Honoré alkaline complex (carbonatite-syenite), lesser-known minor subsurface carbonatite intrusions and several sets of lamprophyre (sl) dykes. Flat-lying, north-dipping dykes (l-100 cm) that crop out close the Saguenay River/Fjord were formed by multiple intrusions of a very fluid magma. The dykes are continuously variable in composition from carbonatite to ultramafic lamprophyre. Olivine phenocrysts (l-3 mm) are pseudomorphed by serpentine but phlogopite phenocrysts (l-5 mm) are well preserved in a matrix of a fine-grained serpentine, chlorite and carbonate. A few dykes are phoscorites, with abundant phenocrysts of phlogopite, oxides, apatite and accessory baddeleyite. In all dykes, the matrix may have been originally fine-grained or even glassy, and subsequently altered by water dissolved in the original magma. Several dykes contain abundant xenoliths: mostly crustal and possibly one of mantle origin. Low-carbonate dykes have a narrow range in Sr isotopes (0.7030-0.7033) versus the wider range of high-carbonate dykes (0.7032-0.7046), but this distinction is not seen in eNd (3.4-4.9). Overall, it appears that each batch of magma was small and came from independent mantle sources. Recently, we found a new set of vertical, NW-directed lamprophyres around the Baie des Ha! Ha!, about 15 km south of the main swarm. They have phlogopite phenocrysts to 50 mm and olivine pseudomorphs. Their contrasting orientation suggests that they have a different age to the Saguenay River dykes, but they have yet to be dated. The overall pattern is of an extensive mantle source that delivered small volumes of volatile-rich ultramafic magmas over a long period. We consider that some of these magma batches accumulated and differentiated in a magma chamber beneath the Saint-Honoré alkaline complex, whereas others rose uninterrupted to high levels of the crust where they were emplaced as dykes.
DS1998-0097
1998
Bedarski, J.Bedarski, J., Leckie, D., De Paoli, G.Gold recovery and kimberlite/diamond indicators from de Bonita Upland, Alberta.Geological Survey of Canada Open File, No. 3601, 7p. $ 10.50AlbertaGeochemistry, Mineralogy - indicators
DS200412-0122
2004
Bedell, R.Bedell, R.Remote sensing in mineral exploration.SEG Newsletter, No. 58, July pp. 1,8-14.TechnologyOverview - remote sensing ( not specific to diamonds)
DS201112-0557
2011
Bedell, R.L.Kruse,F.A., Bedell, R.L., Taranik, J.V., Peppin, W.A., Weatherbee, O., Calvin, W.M.Mapping alteration minerals at prospect, outcrop and drill core scales using imagining spectroscopy.International Journal of Remote Sensing, Vol. 33, 6, pp. 1780-1798.GlobalSpectroscopy - not specific to diamonds
DS1993-0100
1993
Bedell, R.L.Jr.Bedell, R.L.Jr.GIS and the geosciences.. seminar outlineGeological Society of America short course, 200pGlobalBook -table of contents, GIS
DS1994-0133
1994
Bedell, R.L.Jr.Bedell, R.L.Jr.GIS for the GeosciencesGeological Society of America (GSA) Short Course, 200p. approx. $ 20.00GlobalBook -table of contents, Computer -GIS Program
DS1997-0894
1997
Bedford, C.M.Pearce, N.J.G., Leng, M.J., Emeleus, C.H., Bedford, C.M.The origins of carbonatites and related rocks from the Gronnedal Ikanepheline syenite complex. C-O-Sr evid.Mineralogical Magazine, No. 407, August pp. 515-530.Greenland, south GreenlandCarbonatite
DS1997-0085
1997
Bedford, S.Bedford, S., Van der Steen, T.Extending the limits of subsea earthmovingWorld Diamond Conference, held Oct 7-8, 17p.GlobalTechnology - marine mining, Bulk sampling
DS201212-0063
2012
Bedini, A.Bedini, A., Ehrman, S., Nunziante Cesaro, S., Pasini, M., Rapinesi, I.A., Sali, D.The Vallerano diamond from ancient Rome: a scientific study.Gems & Gemology, Vol. 48, 1, pp.TechnologyDiamond - notable
DS201212-0064
2012
Bedini, A.Bedini, A., Ehrman, S., Nunziante Cesaro, S., Pasini, M., Rapinesi, I.A., Sali, D.The Vallerano diamond from ancient Rome: a scientific study.Gems & Gemology, Vol. 48, 1, Spring pp. 39-41.GlobalHistory - diamond notable
DS1995-0130
1995
Bedini, R.M.Bedini, R.M.Mobilization of trace elements during melt rock reactions in the lithospheric mantle: an ICP MS study.Terra Nova, Abstract Vol., p. 338.MantleXenoliths
DS1995-0131
1995
Bedini, R.M.Bedini, R.M., Bodinier, J.L., Dautria, J.M., Morten, L.Superimposed metasomatic processes in lithospheric mantle beneath East African Rift: a single melt sourceProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 44-46.GlobalMetasomatism, Xenoliths
DS1996-0145
1996
Bedini, R.M.Bodinier, J.L., Merlet, C., Bedini, R.M., et al.Distribution of niobium, tantalum - highly incompatible trace elements lithospheric mantle: spinel paradox.Geochimica et Cosmochimica Acta, Vol. 60, No. 3, Feb. pp. 545-550.MantleSpinels, Lithosphere
DS1998-0098
1998
Bedini, R.M.Bedini, R.M., Bodinier, J.L.Distribution of incompatible trace elements between the constituents of mantle spinel peridotites: inversionMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 135-6.MantlePeridotites, Lithophile trace elements
DS1998-0099
1998
Bedini, R.M.Bedini, R.M., Bodinier, J.L., Dautria, J.M., Morten, L.Evolution of large-ion lithophile elements (LILE) enriched small melt fractions in the lithospheric mantle:case study from East African Rift.Earth and Planetary Science Letters, Vol. 153, No. 1-2, pp. 67-83.GlobalEast African Rift, Tectonics, Mantle peridotites
DS1998-1607
1998
Bedini, R.M.Xu, Y.G., Bodinier, J.L., Bedini, R.M., Menzies, M.A.Xenolith evidence for melt rock reaction at the lithosphere plumeboundary.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1671-2.FrancePetrography, geochemistry, Harzburgites, Boree P type
DS2003-0840
2003
Bedini, R.M.Lorand, J.P., Reisberg, L., Bedini, R.M.Platinum group elements and melt percolation processes in Sidamo spinel peridotiteChemical Geology, Vol. 196, 1-4, pp. 57-75.EthiopiaXenoliths
DS2003-0841
2003
Bedini, R.M.Lorand, J-P., Reisberg, L., Bedini, R.M.Platinum group elements and melt percolation processes in Sidamo spinel peridotiteChemical Geology, Vol. 196, 1-4, May 15, pp. 57-75.EthiopiaTectonics, Gregory Rift
DS200412-0123
2004
Bedini, R.M.Bedini, R.M., Blichert-Toft, J., Boyet, M., Albarede, F.Isotopic constraints on the cooling of the continental lithosphere.Earth and Planetary Science Letters, Vol. 223, 1-2, June, 30, pp. 99-111.Africa, South AfricaGarnet peridotite xenoliths, radiometric ages, geotherm
DS200412-1174
2003
Bedini, R.M.Lorand, J.P., Reisberg, L., Bedini, R.M.Platinum group elements and melt percolation processes in Sidamo spinel peridotite xenoliths Ethiopia, East African Rift.Chemical Geology, Vol. 196, 1-4, pp. 57-75.Africa, EthiopiaXenoliths
DS200412-1175
2003
Bedini, R.M.Lorand, J-P., Reisberg, L., Bedini, R.M.Platinum group elements and melt percolation processes in Sidamo spinel peridotite xenoliths, Ethiopia, East African Rift.Chemical Geology, Vol. 196, 1-4, May 15, pp. 57-75.Africa, EthiopiaTectonics, Gregory Rift
DS200412-1653
2004
Bedini, R.M.Reisberg, L., Lorand, J.P., Bedini, R.M.Reliability of Os model ages in pervasively metasomatized continental mantle lithosphere: case study Sidamo spinel peridotite xeChemical Geology, Vol. 208, 1-4, pp. 119-140.Africa, EthiopiaGeochronology, metasomatism
DS1998-0100
1998
Bednarski, J.Bednarski, J., Leckie, D., De Paoli, G.Gold recovery and kimberlite diamond indicators from Cripple Creek, Rocky Mountain Foothills, Alberta.Geological Survey of Canada (GSC) Open File, No. 3602, p. 6.AlbertaGeochemistry
DS1998-0101
1998
Bednarski, J.Bednarski, J., Leckie, D., De Paoli, G.Gold recovery and kimberlite diamond indicators from Del Bonita Upland, Alberta.Geological Survey of Canada (GSC) Open File, No. 3602, p. 8.AlbertaGeochemistry
DS1998-0842
1998
Bednarski, J.Leckie, D., Bednarski, J., De Paoli, G.Gold recovery and kimberlite/diamond indicators from Rocky MountainFoothills, Alberta.Geological Survey of Canada Open File, No. 3602, 6p. $ 10.50AlbertaGeochemistry, Mineralogy - indicators
DS1998-0843
1998
Bednarski, J.Leckie, D.A., Bednarski, J., De Paoli, G.A report on gold recovery and kimberlite/ diamond indicators from a stream sample in the S. Rocky Mtns.Calgary Mining Forum, Apr. 8-9, p. 57. poster abstractAlbertaGeochemistry - heavy minerals
DS1994-1026
1994
Bednarski, J.M.Lemmen, D.S., Duk-Rodkin, A., Bednarski, J.M.Late glacial drainage systems along the northwestern margin of the Laurentide ice sheet.Quat. Science Reviews, Vol. 13, pp. 805-828.Northwest Territories, British Columbia, MontanaGeomorphology
DS1999-0054
1999
Bednarski, J.M.Bednarski, J.M.Quaternary geology of northeastern AlbertaGeological Survey of Canada Bulletin., No. 535, 29p.AlbertaGeomorphology, Map - 1: 100, 000
DS1999-0055
1999
Bednarski, J.M.Bednarski, J.M.Geology and geochemistry of surficial depositsGeological Survey of Canada (GSC) Open File, No. 3714, pp. C1-Northwest Territories, NunavutGeochemistry
DS1990-1073
1990
Bednarz, U.Muenow, D.W., Garcia, M.O., Aggrey, K.E., Bednarz, U., SchminckeVolatiles in submarine glasses as a discriminant of tectonic origin:application to the Troodos ophioliteNature, Vol. 343, No. 6254, January 11, pp. 159-161CyprusOphiolite, Tectonic origin
DS200412-2023
2004
Bedrosian, P.Unsworth, M., Wenbo, W., Jones, A.G., Li, S., Bedrosian, P., Booker, J., Sheng, J., Ming, D., Handong, T.Crustal and upper mantle structure of northern Tibet imaged with magnetotelluric data.Journal of Geophysical Research, Vol. 109, B2, Feb. 13, 10.1029/2002 JB002305Asia, TibetTectonics, geophysics - seismics
DS201312-0067
2013
Bedrosian, P.A.Bedrosian, P.A., Feucht, D.W.Structure and tectonics of the northwestern United States from EarthSCope USArray magnetotelluric data.Earth and Planetary Science Letters, Vol. 402, pp. 275-289.United StatesGeophysics - Magnetotelluric
DS1981-0077
1981
Bedson, P.Bedson, P., Hamilton, D.L.Kimberlites, Carbonatites and Liquid ImmiscibilityIn: Fifth progress report of research support by N.E.R.C. 1978- 1980, Progress in experimental petrology, GBR, Vol. 5, pp. 29GlobalCarbonatite
DS1986-0336
1986
Bedson, P.Hamilton, D.L., Bedson, P.Carbonatites by liquid immiscibilityGeological Association of Canada (GAC) Annual Meeting, Vol. 11, p. 77. (abstract.)GlobalCarbonatite
DS1988-0288
1988
Bedson, P.Hamilton, D.L., Bedson, P.Distribution of trace elements between immiscible silicate and carbonatitemeltsTerra Cognita, Vol. 8, No. 1, Winter 1988 p. 65. Abstract onlyGlobalBlank
DS1989-0577
1989
Bedson, P.Hamilton, D.L., Bedson, P., Esson, J.The behaviour of trace elements in the evolution of carbonatitesCarbonatites -Genesis and Evolution, Ed. K. Bell Unwin Hyman Publ, pp. 405-427TanzaniaExperimental Petrology, Oldoinyo Lengai
DS201212-0065
2011
Beealuva, L.Beealuva, L., Dianchini, G., Wilson, M.Volcanism and evolution of the African lithosphere.Geological Society of America Special Publication, No. 478, 331p. US $ 95.AfricaTectonics - eastern Africa
DS201212-0678
2012
Beeby, A.Smith, E.M., Kopylova, M.G., Nowell, G.M., Pearson, D.G., Ryder, J., Afanasev, V.P.D., Beeby, A.The contrast in trace element chemistry and volatile composition between fluid inclusions n fibrous and octahedral diamonds.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Ontario, WawaDiamond inclusions
DS1960-1071
1969
Beecher, H.E.Beecher, H.E.The Diamond Deposits of Yakutia. Translation of Almazy Mestorozhdenii Yakutii, L959London: Cast., RussiaKimberlite, Kimberley, Janlib
DS2000-0676
2000
Beekman, F.Moisio, K., Kaikkonen, P., Beekman, F.Rheological structure and dynamic response of the DSS profile Baltic in the southeast Fennoscandian Shield.Tectonophysics, Vol. 320, No. 3-4, May pp. 175-94.Finland, ScandinaviaGeodynamics, tectonics, Geophysics - seismics
DS200712-1077
2007
Beekman, F.Tesauro,M., Kaban, M.K., Cloetingh, S.A.P.L., Hare, N.J., Beekman, F.3D strength and gravity anomalies of the European lithosphere.Earth and Planetary Science Letters, Vol. 263, 1-2, Nov. 15, pp. 56-73.EuropeGeophysics - gravity
DS201412-0976
2013
Beekman, F.Willingshofer, E., Sokoutis, D., Beekman, F., Cloetingh, S.Subduction and deformation of the continental lithosphere in response to plate and crust-mantle coupling.Geology, Vol. 41, pp. 1239-1242.MantleSubduction
DS201606-1103
2016
Beekman, F.Lavecchia, A., Clark, S.A., Beekman, F., Cloetingh, S.A.P.L., Burov, E.Thermal perturbation, mineral assemblages and rheology variations by dyke emplacement in the crust.Tectonics, in press availableMantleBasaltic dykes, two layered continental crust

Abstract: We constructed a thermomechanical model to examine the changes in rheology caused by the periodic intrusion of basaltic dykes in a two-layered continental crust. Dyke intrusion can locally change the mineralogical composition of the crust in space and time as a result of temperature-induced metamorphism. In our models we paid particular attention to determine how different mineral assemblages and reaction kinetics during metamorphism impact on the thermomechanical behavior of the crust, in terms of differential stress values. We investigated several lithologies characteristic for intracontinental crust: (1) a quartz-feldspathic crust (QF), (2) a crust with a mineralogical assemblage resembling the average chemical composition occurring in literature (CC), and (3) a micaschist crust (MS). Our model shows that temperature profiles are weakly influenced by metamorphism, with negligible variations in the T-t paths. The results indicate that intrusion-induced changes in the crustal rheology are strongly dependent on mineralogical assemblage variation. The strength of a dyke aureole in the upper crust increases during dyke emplacement, which may cause migration of later dykes and influence the dyke spacing. In contrast, in the lower crust the strength of a dyke aureole decreases during dyke emplacement. Fast kinetics results in a ductile lower crust in proximity of the dykes, whereas slower kinetics leads to the formation of partial melts and subsequent switch from ductile to brittle behavior. Lithology exerts a dominant role on the quantity of melt produced, with higher volume percentages occurring in the MS case study. Produced melts may migrate and support acidic volcanic activity.
DS201706-1089
2017
Beekman, F.Lavecchia, A., Thieulot, C., Beekman, F., Cloetingh, S., Clark, S.Lithosphere erosion and continental breakup: interaction of extension, plume upwelling and melting.Earth and Planetary Science Letters, Vol. 467, pp. 89-98.Mantlemelting

Abstract: We present the results of thermo-mechanical modelling of extension and breakup of a heterogeneous continental lithosphere, subjected to plume impingement in presence of intraplate stress field. We incorporate partial melting of the extending lithosphere, underlying upper mantle and plume, caused by pressure-temperature variations during the thermo-mechanical evolution of the conjugate passive margin system. Effects of melting included in the model account for thermal effects, causing viscosity reduction due to host rock heating, and mechanical effects, due to cohesion loss. Our study provides better understanding on how presence of melts can influence the evolution of rifting. Here we focus particularly on the role of melting for the temporal and spatial evolution of passive margin geometry and rift migration. Depending on the lithospheric structure, melt presence may have a significant impact on the characteristics of areas affected by lithospheric extension. Pre-existing lithosphere heterogeneities determine the location of initial breakup, but in presence of plumes the subsequent evolution is more difficult to predict. For small distances between plume and area of initial rifting, the development of symmetric passive margins is favored, whereas increasing the distance promotes asymmetry. For a plume-rifting distance large enough to prevent interaction, the effect of plumes on the overlying lithosphere is negligible and the rift persists at the location of the initial lithospheric weakness. When the melt effect is included, the development of asymmetric passive continental margins is fostered. In this case, melt-induced lithospheric weakening may be strong enough to cause rift jumps toward the plume location.
DS201112-0134
2011
Beelieni, G.Callegaro, S., Marzoli, A., Bertrand, H., Reisberg, L., Chiaradia, M., Beelieni, G.Geochemistry of eastern North American CAMP diabase dykes.Goldschmidt Conference 2011, abstract p.614.United States, AppalachiaCentral Atlantic Province .... basaltic
DS1988-0489
1988
Beere, G.M.Mory, A.J., Beere, G.M.Geology of the onshore Bonaparte and Ord Basins in Western AustraliaWestern Australia Geological Survey Bulletin, No. 134, 184pAustraliaBonaparte and Ord Basins, Alluvials
DS2002-0133
2002
Beerling, D.J.Beerling, D.J., Royer, D.L.Fossil plants as indicators of the Phanerozoic global carbon cycleAnnual Review of Earth and Planetary Sciences, Vol.30,pp. 527-56.GlobalCarbon cycle
DS1975-0175
1975
Beerman, E.Rost, F., Beerman, E., Amthauer, G.Chemical Investigation of Pyrope Garnets in the Stockdale Kimberlite Intrusion, Riley County, Kansas.American MINERALOGIST., Vol. 60, PP. 675-680.KansasKimberlite, Central States
DS1984-0492
1984
Beery, J.Mathez, E.A., Blacic, J.D., Beery, J., Maggiore, C., Hollander.Carbon Abundances in Mantle Minerals Determined by Nuclear Reaction Analysis.Geophysical Research. LETTERS, Vol. 11, No. 10, OCTOBER, PP. 947-950.United States, Colorado Plateau, New MexicoXenolith, Crystallography
DS1986-0533
1986
Beery, J.Mathez, E.A., Blacic, J.D., Beery, J., Maggiore, C., Hollander, M.Carbon in olivine by nuclear reaction analysisProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 273-275GlobalBlank
DS1987-0444
1987
Beery, J.Mathez, E.A., Blacic, J.D., Beery, J., Hollander, M., Maggiore, C.Carbon in olivine: results from nuclear reaction analysisJournal of Geophys., Res, Vol. 92, No. B5, April 10, pp. 3500-3506GlobalMantle genesis
DS200612-0114
2006
Beeskow, B.Beeskow, B., Treloar, P.J., Rankin, A.H., Vennemann, T.W., Spangenberg, J.A reassessment of models for hydrocarbon generation in the Khibiny nepheline syenite complex, Kola Peninsula, Russia.Lithos, in press availableRussiaAlkalic
DS1910-0406
1914
Beet, A.J.Beet, A.J.Kimberley: Its History and Diamonds With Summary of the SiegKimberley: Diamond Fields Advertiser, Illustrated Handbook, 92P.South Africa, Griqualand West, Kimberley AreaHistory, Kimberley
DS1900-0533
1907
Beet, G.Beet, G.New Sidelights in the Early DaysDiamond Fields Advertiser Christmas Issue., No. 1907, PP. 2-6.Africa, South AfricaHistory
DS1910-0523
1917
Beet, G.Beet, G., Terpend, T.L.The Romance and Reality of the Vaal Diamond DiggingKimberley: Diamond Fields Advertiser., 117P.South Africa, Cape ProvinceVaal River Diggings, History, Alluvial Diamond Placers
DS1930-0055
1931
Beet, G.Beet, G.The Grand Old Days of the Diamond Fields. Memories of Past Times with Diggers of Diamondia.Cape Town: Maskew Miller., 192P. (REPRINT 1971).South AfricaHistory, Kimberley, Janlib
DS1920-0148
1923
Beetz, P.F.W.Beetz, P.F.W.Ueber Den Ursprung der Achatgerolle und der Gerolle And ererquarz Mineralien in Den Diamant seifen an der Kuste Suedwestafrikas.Neues Jahrbuch fnr Mineralogie, PP. 347-380.Southwest Africa, NamibiaMineralogy, Littoral Diamond Placers
DS1930-0012
1930
Beetz, P.F.W.Beetz, P.F.W.Angola and the Belgian Congo Diamond FieldsSoc. International Forestiere Et Minere Du Congo, UNPUBL.Angola, Zaire, Central AfricaGeology
DS1930-0013
1930
Beetz, P.F.W.Beetz, P.F.W.Process of Concentration in Alluvial and Allied Diamond Placers of Southwest, South, Central and East Africa #2International CONGRESS Mines 6TH, Vol. 1, PP. 25-42.South Africa, East Africa, West Africa, Southwest Africa, NamibiaMining, Alluvial Diamond Placers
DS1930-0014
1930
Beetz, P.F.W.Beetz, P.F.W.Process of Concentration in Alluvial and Allied Diamond Placers of Southwest, South, Central and East Africa #1International CONGRESS Mines 6TH, Vol. 6, PP. 49-68.South Africa, Southwest Africa, East Africa, West Africa, NamibiaMining, Alluvial Diamond Placers
DS1920-0181
1924
Beetz, W.Beetz, W.On a Great Trough Valley in the NamibGeological Society of South Africa Transactions, Vol. 27, PP. 1-38.Southwest Africa, NamibiaDiamond, Kimberlite, Tectonics, Witputz
DS1920-0182
1924
Beetz, W.Beetz, W., Kaiser, E.Das Suedliche Diamanten gebiet Suedwestafrikas. Erlauterungen Zu Einer Geologischen Spezialkarte des Sued lichen Diamantgebietes.Berlin: D. Reimer., MAP 1: 25, 000.Southwest Africa, NamibiaDiamond Occurrences
DS1920-0269
1926
Beetz, W.Beetz, W.Die Lagerungungs verhaltnisse Alteren Schichten in der Sued lichen Namib.Die Diamantenwueste Suedwest Afrika. Kaiser, E.ed., Vol. 1, PP.123-165.Southwest Africa, NamibiaGeology
DS1920-0270
1926
Beetz, W.Beetz, W.Ueber Einen Grossen Grabeneinbruch in der Namib Suedwest Afrika.In: Die Diamantenwueste Suedwest Afrika, Kaiser, E. Ed., Vol. 1, PP. 166-189.Southwest Africa, NamibiaGeology, Tectonics
DS1920-0271
1926
Beetz, W.Beetz, W.Die Tertiaerablagerungen der KuestennamibDie Diamantenwueste Suedwest Afrika, Kaiser, E. Ed., Vol. 2, PP. 1-54.Southwest Africa, NamibiaStratigraphy, Littoral Diamond Placers
DS1920-0272
1926
Beetz, W.Beetz, W.Die Konkip und die NamaformationDie Diamantenwueste Sued West Afrika, Kaiser, E.ed., Vol. 1, PP. 92-122.Southwest Africa, NamibiaStratigraphy, Regional Geology
DS201809-1994
2018
Befus, K.Bassoo, R., Befus, K.The magmatic origin and provenance of Guyana's diamonds: a first look.Goldschmidt Conference, 1p. AbstractSouth America, Guyanaalluvials

Abstract: Placer diamonds from the Proterozoic and Paleoproterozoic terranes of the Guiana Shield in Guyana, have an enigmatic geochemistry and provenance. Diamonds may be derived from kimberlite intrusions, but no outcrops have been identified in the dense tropical terrain. Alternatively, they may be weathered from 1.79 Ga, NE-SW trending mafic dykes of the Avanavero suite or eroded from 1.95 to 1.78 Ga sandstones and conglomerates of the Roraima Formation into recent alluvial river bed deposits [1]. To resolve these uncertainties, we acquired initial samples of 212 placer diamonds from different locations in Guyana for study. Diamonds range in size from 1.1 mm to 1.7 mm with a mean diameter of 1.3±0.2 mm. Diamonds are primarily dodecahedral to cubic, with lesser octahedral and minor macle forms. The diamonds are colourless to brown and most have a green surface skin. Diamond surfaces show diverse textures, including frosting, edge abrasions, network patterns, and ruts. Dissolution features are common and include point bottom trigons, with a diameter of 21±15 µm. We measured N concentrations using FTIR (measured at 1282 cm-1). Diamonds are Type IaA-IaB with N concentrations of 55 ppm to 210 ppm. Total N ppm vs %NB ratios indicate mantlederived conditions of 1200 ºC and 4.7 GPa. Calculated Shields Parameter shear stresses of 0.0009 dynes/cm2 to 0.0016 dynes/cm2 suggest diamonds could be transported in bedloads derived from medium to very coarse sandstones or coarse- to pebble-sized kimberlitic lithics. Guyana’s diamonds are dissimilar to those from other regions of the Guiana Shield. To further this comparison, we studied 8 diamonds from Eastern Venezuela and Western Colombia on loan from the Smithsonian Museum of Natural History. Compared to Venezuelan and Colombian diamonds, Guyana’s diamonds are dodecahedral, and have a higher degree of dissolution textures, suggestive of higher ƒO2 conditions during kimberlite magma ascent. We will continue to study Guyana’s diamonds using a combination of electron microprobe, µXRD, and Raman analyses of inclusions. Taken together we hope to infer the provenance of Guyana’s placer diamonds and the petrology of the mantle rocks from which they were derived.
DS202009-1610
2020
Befus, K.S.Bassoo, R., Befus, K.S., Liang, P., Forman, S.L., Sharman, G.Deciphering the enigmatic origin of Guyana's diamonds.The American Mineralogist, in press available 59p. PdfSouth America, Guyanadiamond crystallography

Abstract: Diamonds have long been mined from alluvial terrace deposits within the rainforest of Guyana, South America. No primary kimberlite deposits have been discovered in Guyana, nor has there been previous studies on the mineralogy and origin of the diamonds. Paleoproterozoic terranes in Guyana are prospective to diamond occurrences because the most productive deposits are associated spatially with the eastern escarpment of the Paleoproterozoic Roraima Supergroup. Geographic proximity suggests that the diamonds are detrital grains eroding from the <1.98 Ga conglomerates, metamorphosed to zeolite and greenschist facies. The provenance and paragenesis of the alluvial diamonds are described using a suite of placer diamonds from different locations across the Guiana Shield. Guyanese diamonds are typically small, and those in our collection range from 0.3 to 2.7 mm in diameter; octahedral and dodecahedral, with lesser cubic and minor macle forms. The diamonds are further subdivided into those with abraded and non-abraded surfaces. Abraded diamonds show various colors in cathodoluminescence whereas most non-abraded diamonds appear blue. In all populations, diamonds are predominantly colorless, with lesser brown to yellow and very rare white. Diamonds are predominantly Type IaAB and preserve moderate nitrogen aggregation and total nitrogen concentrations ranging from trace to ~1971 ppm. The kinetics of nitrogen aggregation indicate mantle-derived residence temperatures of 1124 ± 100 ºC, assuming residence times of 1.3 Ga and 2.6 Ga for abraded and non-abraded diamonds respectively. The diamonds are largely sourced from the peridotitic to eclogitic lithospheric upper mantle based on both d13C values of -5.82 ± 2.45‰ (VPDB-LSVEC) and inclusion suites predominantly comprised of forsterite, enstatite, Cr-pyrope, chromite, rutile, clinopyroxene, coesite, and almandine garnet. Detrital, accessory minerals are non-kimberlitic. Detrital zircon geochronology indicates diamondiferous deposits are predominantly sourced from Paleoproterozoic rocks of 2079 ± 88 Ma.
DS1982-0485
1982
Begemann, F.Ott, U., Begemann, F., Lohr, H.P.Diamond Bearing Meteorite Alha 77287; Implication from Noble Gases.Meteoritical Society 45th. Annual Meeting, Vol. 17, No. 4, P. 266. (abstract.).GlobalMeteorite
DS1984-0570
1984
Begemann, F.Ott, U., Lohr, H.P., Begemann, F.Ureilites: the Case of Missing Diamonds and a New Neon Component.Meteorites, Vol. 19, No. 4, PP. 287-GlobalBlank
DS1986-0626
1986
Begemann, F.Ott, U., Lohr, H.P., Begemann, F.Noble gases in ALH 82130-comparison with ALHA 7810 And diamond bearingurelitesMeteoritics, Vol. 21, No.4, December 31, pp. 477-478GlobalMeteorites
DS1987-0826
1987
Begemann, F.Zadnik, M.G., Smith, C.B., Ott, U., Begemann, F.3HE/4HE in diamonds: higher than solarTerra Cognita, Vol. 7, No. 2, 1p. abstractSouth AfricaFinsch, helium
DS1993-1658
1993
Begemann, F.Verchovsky, A.B., Ott, U., Begemann, F.Implanted radiogenic and other noble gases in crustal diamonds from northern Kazakhstan.Earth and Planetary Science Letters, Vol. 120, No. 3-4 December pp. 87-102.Russia, KazakhstanBlank
DS1993-1009
1993
Begg, E.J.B.McNerney, N., Dippenaar, K., Snyman, C.P., Begg, E.J.B.The geology of the Greenview lamprophyric breccia ventSouth African Journal of Geology, Vol. 95, No. 5-6, pp. 194-202South AfricaBreccia, Alkaline rocks
DS200512-0813
2005
Begg, G.O'Reilly, S.Y., Hronsky, J., Griffin, W.L., Begg, G.The evolution of lithospheric domains: a new framework to enhance mineral exploration targeting.Mineral deposit Research: Meeting the Global Challenge. 8th Biennial SGA Beijing, Aug. 18-22, 2005. Springer, Chapter 1-11, pp. 41-44.MantleTectonics
DS200912-0041
2009
Begg, G.Begg, G., Belousova, E., Griffin, W.L., O'Reilly, S.Y., Natapov, L.Continental versus crustal growth: resolving the paradox.Goldschmidt Conference 2009, p. A103 Abstract.MantleArchean - Boundary
DS200912-0266
2009
Begg, G.Griffin, W.L., Begg, G., O'Reilly, S.Y., Afonso, J.C.Paleo-Archean generation of the continental lithosphere.Goldschmidt Conference 2009, p. A466 Abstract.MantleKimberlite xenoliths
DS200912-0553
2009
Begg, G.O'Reilly, S.Y., Zhang, M., Griffin, W.L., Begg, G., Hronsky, J.Ultradeep continental roots and their oceanic remnants: a solution to the geochemical 'mantle reservoir' problem?Lithos, In press available 41p.MantleGeochemistry
DS201112-0387
2011
Begg, G.Griffin, W.L., Begg, G., O'Reilly, S.Y., Pearson, N.J.Ore deposits and the SCLM.Goldschmidt Conference 2011, abstract p.946.MantleKimberlites - low degree melting prev. metasomatised
DS200912-0042
2009
Begg, G.C.Begg, G.C., Griffin, W.L., Natapov, O'Reilly, Grand, O'Neill, Hronsky, Poudjom Djomeni, Swain, Deen, BowdenThe lithospheric architecture of Africa: seismic tomography, mantle petrology, and tectonic evolution.Geosphere, Vol. 5, pp. 23-50.AfricaGeophysics - seismic, tectonics
DS200912-0268
2009
Begg, G.C.Griffin, W.L., O'Reilly, S.Y., Afonso, J.C., Begg, G.C.The composition and evolution of lithospheric mantle: a re-evaluation and its tectonic implications.Journal of Petrology, Vol. 50,no. 7,. pp. 1185-1204.MantleTectonics
DS201012-0048
2010
Begg, G.C.Belousova, E.A., Kostitsyn, Y.A., Griffin, W.L., Begg, G.C., O'Reilly, S.Y.The growth of the continental crust: constraints from zircon Hf isotope data.Lithos, Vol. 119, pp. 457-466.MantleGeochronology
DS201112-0388
2011
Begg, G.C.Griffin, W.L., Begg, G.C., Dunn, D., O'Reilly, S.Y., Natapov, L.M., Karlstrom, K.Archean lithospheric mantle beneath Arkansas: continental growth by microcontinent accretion.Geological Society of America Bulletin, Vol. 123, 9-10, pp. 1763-1775.United States, ArkansasPrairie Creek lamproites
DS201112-0389
2011
Begg, G.C.Griffin, W.L., Begg, G.C., Dunn, D., O'Reilly, S.Y., Natapov, L.M., Karlstrom, K.Archean lithospheric mantle beneath Arkansas: continental growth by microcontinent accretion.Geological Society of America Bulletin, Vol. 123, 9/10 pp. 1763-1775.United States, ArkansasPrairie Creek lamproites
DS201312-0335
2013
Begg, G.C.Griffin, W.L., Begg, G.C., O'Reilly, S.Y.Continental root control on the genesis of magmatic ore deposits.Nature Geoscience, 6p. On line Oct 13TechnologyMagmatism
DS201312-0667
2013
Begg, G.C.O'reilly, S., Griffin, W.L., Begg, G.C., Pearson, D.G., Hronsky, J.M.A.Archean lithospheric mantle: the fount of all ores?Goldschmidt 2013, AbstractMantleMagmatism
DS201510-1773
2015
Begg, G.C.Jessell, M.W., Begg, G.C., Miller, M.S.The geophysical signatures of the West African Craton.Precambrian Research, in press available, 22p.Africa, West AfricaGeophysics - gravity

Abstract: This paper examines existing and newly compiled geophysical representations of the West African Craton (WAC) in terms of its large-scale tectonic architecture. In order to build an interpretation with a significant depth extent we draw upon a range of geophysical data, principally seismic tomographic inversions, receiver functions, gravity and magnetics. We present these results as a series of layers providing a series of depth slices though the cratonic lithosphere. The different geophysical methods suggest partitioning of the WAC into two tectonic elements at the largest scale which is observed in both seismic tomographic images, lithosphere-asthenosphere boundary (LAB) models and long wavelength gravity signals. The different models of the Moho, or crust-mantle boundary, based on these gravity or seismic datasets show little or no correlation, either for short or long-wavelength features, and show little correlation with new receiver function inferred crustal thickness estimates. Manual interpretation of low-wavelength gravity and magnetic data suggest a possible continuation of the WAC across the western margin of the modern boundary, and also highlight distinct domains interpreted to be of Birimian age.
DS201711-2501
2015
Begg, G.C.Begg, G.C., Griffin, W.L., O'Reilly, S.Y., Natapov, L.Geoscience dat a integration: insights into mapping lithospheric architecture.ASEG-PESA 2015, 2 p. abstract Mantledata integration

Abstract: In order to develop a 4D understanding of the architecture of the entire lithosphere, it is necessary to embrace integration of multi-disciplinary, multi-scale data in a GIS environment. An holistic understanding has evolved whereby geologic, geochemical and geophysical signals are consistent with a subcontinental lithospheric mantle (SCLM) dominated by a mosaic of domains of Archean ancestry, variably overprinted by subsequent tectonothermal events. Pristine Archean SCLM is mostly highly depleted (high Mg#), low density, high velocity and highly resistive, and preserves intact Archean crust. There is a first order relationship between changes to these signals and the degree of tectonothermal overprint (by melts, fluids). Continental crust is comprised largely of reconstituted Archean components, variably diluted by juvenile addition, symptomatic of the various overprinting events. These events impart crustal fabrics and patterns dictated by SCLM architecture, influenced by the free surface and crust-mantle decoupling.
DS1994-0427
1994
Begg, M.Dias, A.K., Begg, M.Environmental policy for sustainable development of natural resourcesNatural Resources forum, Vol. 18, No. 4, pp. 275-286GlobalLegal, Environmental
DS202101-0011
2020
Begheim, C.Fischer, K.M., Rychert, C.A., Dalton, C.A., Miller, M.S., Begheim, C., Schutt, D.L.A comparison of oceanic and continental mantle lithsophere.Physics of the Earth and Planetary Interiors, Vol. 309, 106600, 20p. PdfMantlemelting

Abstract: Over the last decade, seismological studies have shed new light on the properties of the mantle lithosphere and their physical and chemical origins. This paper synthesizes recent work to draw comparisons between oceanic and continental lithosphere, with a particular focus on isotropic velocity structure and its implications for mantle temperature and partial melt. In the oceans, many observations of scattered and reflected body waves indicate velocity contrasts whose depths follow an age-dependent trend. New modeling of fundamental mode Rayleigh waves from the Pacific ocean indicates that cooling plate models with asymptotic plate thicknesses of 85-95 km provide the best overall fits to phase velocities at periods of 25 s to 250 s. These thermal models are broadly consistent with the depths of scattered and reflected body wave observations, and with oceanic heat flow data. However, the lithosphere-asthenosphere velocity gradients for 85-95 km asymptotic plate thicknesses are too gradual to generate observable Sp phases, both at ages less than 30 Ma and at ages of 80 Ma or more. To jointly explain Rayleigh wave, scattered and reflected body waves and heat flow data, we propose that oceanic lithosphere can be characterized as a thermal boundary layer with an asymptotic thickness of 85-95 km, but that this layer contains other features, such as zones of partial melt from hydrated or carbonated asthenosphere, that enhance the lithosphere-asthenosphere velocity gradient. Beneath young continental lithosphere, surface wave constraints on lithospheric thickness are also compatible with the depths of lithosphere-asthenosphere velocity gradients implied by converted and scattered body waves. However, typical steady-state conductive models consistent with continental heat flow produce thermal and velocity gradients that are too gradual in depth to produce observed converted and scattered body waves. Unless lithospheric isotherms are concentrated in depth by mantle upwelling or convective removal, the presence of an additional factor, such as partial melt at the base of the thermal lithosphere, is needed to sharpen lithosphere-asthenosphere velocity gradients in many young continental regions. Beneath cratons, numerous body wave conversions and reflections are observed within the thick mantle lithosphere, but the velocity layering they imply appears to be laterally discontinuous. The nature of cratonic lithosphere-asthenosphere velocity gradients remains uncertain, with some studies indicating gradual transitions that are consistent with steady-state thermal models, and other studies inferring more vertically localized velocity gradients.
DS200412-0124
2004
Beghein, C.Beghein, C., Trampert, J.Probability functions for radial anisotropy: implications for the upper 1200 km of the mantle.Earth and Planetary Science Letters, Vol. 217, 1-2, Jan. 1, pp. 151-162.MantleGeophysics - seismics, transition zone
DS201312-1002
2013
Beghein, C.Yuan, K., Beghein, C.Seismic anisotropy changes across upper mantle phase transitions.Earth and Planetary Science Letters, Vol. 374, pp. 132-144.MantleDeep water cycle
DS1991-0695
1991
Beghoul, N.Hearn, T., Beghoul, N., Barazangi, M.Tomography of the western United States from regional arrival timesJournal of Geophysical Research, Vol. 96, No. B 10, September 10, pp. 16, 369-16, 381Basin and Range, CordilleraCrust -thickness, Geophysics -seismics
DS200412-1903
2003
Begin, N.St.Onge, M.R., Wodicka, N., Scott, D.J., Corrigan, D., Carmichael, D.M., Dubach, K., Berniolles, F., Begin, N.Thermal architecture of a continent-continent collision zone: a Superior to Rae Craton transect of Trans-Hudson Orogen ( Quebec-Geological Association of Canada Annual Meeting, Abstract onlyCanada, QuebecGeothermometry
DS1992-0106
1992
Begin, N.J.Begin, N.J.Contrasting mineral isograd sequences in metabasites of the Cape SmithBelt, northern Quebec, Canada: three new bathograds for mafic rocksJournal of Metamorphic Geology, Vol. 10, pp. 685-704Quebec, Labrador, UngavaStructure, Mafic rocks, Metamorphism, mafics, Metabasites
DS1989-0098
1989
Begou, P.Begou, P., Amosse, J., Fischer, W., Piboule, M.platinum group elements (PGE) distribution into the Lherz massive spinel peridotite (Ariege) France. Preliminary results.(in French)Comptes Rendus, (in French), Vol. 309, No. 11, October 12, pp.1177-1182FrancePlatinuM., Lherzolite
DS201805-0990
2018
Begue, F.Wang, H.A.O., Cartier, L.E., Baumgartner, L.P., Bouvier, A-S., Begue, F., Chalain, J-P., Krzemnicki, M.S.A preliminary SIMS study using carbon isotopes to separate natural from synthetic diamonds.Journal of Gemmology, Vol. 36, 1, pp. 38-43.Technologysynthetics
DS200712-0213
2007
Begun, G.M.Dai, S., Young, J.P., Begun, G.M., Mamantov, G.Temperature measurement by observation of the Raman spectrum of diamond.Applied Spectroscopy, Vol. 46, 2, pp. 375-377.TechnologySpectroscopy
DS1980-0057
1980
Behal, S.C.Behal, S.C., Srivastava, M.Mineral Processing Plant for Recovery of Diamonds at Jungel, Mirzapur District, Uttar Pradesh.India Geological Survey Spec. Publishing, No. 4, PP. 633-637.India, Uttar PradeshMining Engineering
DS200712-0063
2007
Behara, L.Behara, L., Sain, K.Crustal velocity structure of the Indian shield from deep seismic sounding and receiver function studies.Journal of the Geological Society of India, Vol. 68, 6. pp. 989-992.IndiaGeophysics - seismics
DS201707-1363
2017
Behera, D.Shaikh, A.M., Patel, S.C., Ravi, S., Behera, D., Pruseth, K.L.Mineralogy of the TK1 and TK4 'kimberlites' in the Timmasamudram cluster, Wajrakur kimberlite field, India: implications for lamproite magmatism in a field of kimberlites and ultramafic lamprophyres.Chemical Geology, Vol. 455, pp. 208-230.Indiadeposit - Wajrakur

Abstract: A mineralogical study of the hypabyssal facies, late Cretaceous macrocrystic pulse of TK1 intrusion and the Mesoproterozoic aphanitic pulse of TK4 intrusion in the Wajrakarur Kimberlite Field of southern India shows that the rocks contain macrocrysts of forsteritic olivine, phenocrysts and microphenocrysts of Al–Na-poor diopside and phlogopite set in a groundmass mainly of Al–Na-poor diopside and phlogopite. Other groundmass minerals are spinel, perovskite and fluorapatite in TK1, and spinel, titanite, chlorite, calcite and gittinsite in TK4. K-richterite and perovskite occur only as inclusions in phlogopite and titanite, respectively in TK4. Late-stage deuteric phases include pyrite and barite in TK1, and strontianite, chalcopyrite, galena and pentlandite in TK4. Diopside microphenocrysts in TK4 exhibit oscillatory zoning with characteristics of diffusion controlled magmatic growth. TK1 spinels show magmatic trend 2 that evolves from magnesiochromite and culminates in titaniferous magnetite, whereas TK4 spinels are less evolved with magnesiochromite composition only. TK1 phlogopites show a simple compositional trend that is typical of lamproite micas, while four distinct growth zones are observed in TK4 phlogopites with the following compositional characteristics: zone I: high Cr2O3 and TiO2 and low BaO; zone II: low Cr2O3; zone III: low TiO2 and high BaO; zone IV: low BaO. Forsterite contents and trace element concentrations reveal two xenocrystic core populations and one magmatic rim population for TK1 olivines. Mineralogically, both TK1 and TK4 are classified as diopside–phlogopite lamproites rather than archetypal kimberlites. The two lamproites are considered to have formed from the same parent magma but crystallised under distinct oxygen fugacity conditions. With elevated content of Fe3 + in phlogopite, spinel and perovskite, TK1 appears to have crystallised in a relatively high oxygen fugacity environment. Multiple growth generations of phlogopite, spinel and fluorapatite in TK4 indicate a complex evolutionary history of the magma. Close spatial and temporal associations of Mesoproterozoic kimberlites and lamproites in southern India can possibly be explained by a unifying model which accounts for the generation of diverse magmas from a range of geochemical resevoirs in a continental rift setting.
DS201805-0975
2018
Behera, D.Shaikh, A.M., Kumar, S.P., Patel, S.C.,Thakur, S.S., Ravi, S., Behera, D.The P3 kimberlite and P4 lamproite, Wajrakur kimberlite field, India: mineralogy, and major and minor element compositions of olivines as records of their phenocrystic vs xenocrystic origin.Mineralogy and Petrology, 16p pdfIndiadeposit - Wajrakarur
DS202010-1853
2020
Behera, D.Kumar, S.P., Shaikh, A.M., Patel, S.C., Sheikh, J.M., Behera, D., Pruseth, K.L., Ravi, S.,Tappe, S.Multi-stage magmatic evidence of olivine-leucite lamproite dykes from Banganapalle, Dharwar craton, India: evidence from compositional zoning of spinel.Mineralogy and Petrology, doi.org/10.1007/s00710-020-00722-y 26p. PdfIndialamproite

Abstract: Mesoproterozoic lamproite dykes occurring in the Banganapalle Lamproite Field of southern India show extensive hydrothermal alteration, but preserve fresh spinel, apatite and rutile in the groundmass. Spinels belong to three genetic populations. Spinels of the first population, which form crystal cores with overgrowth rims of later spinels, are Al-rich chromites derived from disaggregated mantle peridotite. Spinels of the second population include spongy-textured grains and alteration rims of titanian magnesian aluminous chromites that formed by metasomatic interactions between mantle wall-rocks and precursor lamproite melts before their entrainment into the erupting lamproite magma. Spinels that crystallised directly from the lamproite magma constitute the third population and show five distinct compositional subtypes (spinel-IIIa to IIIe), which represent discrete stages of crystal growth. First stage magmatic spinel (spinel-IIIa) includes continuously zoned macrocrysts of magnesian aluminous chromite, which formed together with Al-Cr-rich phlogopite macrocrysts from an earlier pulse of lamproite magma at mantle depth. Crystallisation of spinel during the other four identified stages occurred during magma emplacement at crustal levels. Titanian magnesian chromites (spinel-IIIb) form either discrete crystals or overgrowth rims on spinel-IIIa cores. Further generations of overgrowth rims comprise titanian magnesian aluminous chromite (spinel-IIIc), magnetite with ulvöspinel component (spinel-IIId) and lastly pure magnetite (spinel-IIIe). Abrupt changes of the compositions between successive zones of magmatic spinel indicate either a hiatus in the crystallisation history or co-crystallisation of other groundmass phases, or possibly magma mixing. This study highlights how different textural and compositional populations of spinel provide important insights into the complex evolution of lamproite magmas including clues to elusive precursor metasomatic events that affect cratonic mantle lithosphere.
DS200512-0074
2004
Behera, L.Behera, L., Sain, K., Reddy, P.R.Evidence of underplating from seismic and gravity studies in the Mahanadi delta of eastern India and its tectonic significance.Journal of Geophysical Research, Vol. 109, 12, DOI 10.1029/2003 JB002764IndiaTectonics
DS200612-1301
2006
Behn, M.Silver, P.G., Behn, M., Kelley, K., Schmitz, M., Savage, B.Understanding cratonic flood basalts.Earth and Planetary Science Letters, in pressAfrica, South Africa, RussiaCraton, lithosphere, origin debate
DS200412-0125
2004
Behn, M.D.Behn, M.D., Conrad, C.P., Silver, P.G.Detection of upper mantle flow associated with the African superplume.Earth and Planetary Science Letters, Vol. 224, 3-4, pp. 259-274.Africa, South AfricaGeophysics - seismics, boundary, mantle convection
DS200712-0198
2007
Behn, M.D.Conrad, C.P., Behn, M.D., Silver, P.G.Global mantle flow and the development of seismic anisotropy; differences between the oceanic and continental upper mantle.Journal of Geophysical Research, Vol. 112, B7 B07317.MantleGeophysics - seismics
DS200712-0199
2007
Behn, M.D.Conrad, C.P., Behn, M.D., Silver, P.G.Global mantle flow and the development of seismic anisotropy: difference between the oceanic continental upper mantle.Journal of Geophysical Research, Vol. 112, B7, B07317.MantleGeophysics - seismics
DS200812-1066
2008
Behn, M.D.Silver, P.G., Behn, M.D.Intermittent plate tectonics?Science, Vol. 319, 5859, Jan. 04, pp. 85-87.MantleTectonics
DS201112-0400
2011
Behn, M.D.Hacker, B.R., Kelemen, P.B., Behn, M.D.Differentiation of the continental crust by relamination.Earth and Planetary Science Letters, Vol. 307, 3-4, pp. 501-516.MantleSubduction, bulk analyis
DS201212-0641
2012
Behn, M.D.Shaw, A.M., Hauri, E.H., Behn, M.D., Hilton, D.R., MacPherson, C.G., Sinton, J.M.Long term preservation of slab signatures in the mantle interred from hydrogen isotopes.Nature Geoscience, Vol. 5, March pp, 224-228.MantleTomography - seismics
DS201312-0106
2013
Behn, M.D.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
DS201507-0314
2015
Behn, M.D.Hacker, B.R., Kelemen, P.B., Behn, M.D.Continental lower crust.Annual Review of Earth and Planetary Sciences, Vol. 43, pp. 167-205.MantleSubduction
DS201508-0381
2015
Behn, M.D.Whitehead, J.A., Behn, M.D.The continental drift convection cell. Wilson Cycle)Geophysical Research Letters, Vol. 42, 11, June 16, pp. 4301-4308.GlobalConvection
DS201604-0613
2016
Behn, M.D.Kelemen, P.B., Behn, M.D.Formation of lower continental crust by relamination of bouyant arc lavas and plutons.Nature Geoscience, Vol. 9, 3, pp. 197-205.MantleSubduction

Abstract: The formation of the Earth's continents is enigmatic. Volcanic arc magmas generated above subduction zones have geochemical compositions that are similar to continental crust, implying that arc magmatic processes played a central role in generating continental crust. Yet the deep crust within volcanic arcs has a very different composition from crust at similar depths beneath the continents. It is therefore unclear how arc crust is transformed into continental crust. The densest parts of arc lower crust may delaminate and become recycled into the underlying mantle. Here we show, however, that even after delamination, arc lower crust still has significantly different trace element contents from continental lower crust. We suggest that it is not delamination that determines the composition of continental crust, but relamination. In our conceptual model, buoyant magmatic rocks generated at arcs are subducted. Then, upon heating at depth, they ascend and are relaminated at the base of the overlying crust. A review of the average compositions of buoyant magmatic rocks — lavas and plutons — sampled from the Aleutians, Izu-Bonin-Marianas, Kohistan and Talkeetna arcs reveals that they fall within the range of estimated major and trace elements in lower continental crust. Relamination may thus provide an efficient process for generating lower continental crust.
DS201607-1298
2016
Behn, M.D.Hacker, B.R., Kelemen, P.B., Behn, M.D.Continental lower crust.Annual Review of Earth and Planetary Sciences, Vol. 43, pp. 167-205.MantleMagmatism

Abstract: The composition of much of Earth's lower continental crust is enigmatic. Wavespeeds require that 10 -20% of the lower third is mafic, but the available heat-flow and wavespeed constraints can be satisfied if lower continental crust elsewhere contains anywhere from 49 to 62 wt% SiO2. Thus, contrary to common belief, the lower crust in many regions could be relatively felsic, with SiO2 contents similar to andesites and dacites. Most lower crust is less dense than the underlying mantle, but mafic lowermost crust could be unstable and likely delaminates beneath rifts and arcs. During sediment subduction, subduction erosion, arc subduction, and continent subduction, mafic rocks become eclogites and may continue to descend into the mantle, whereas more silica-rich rocks are transformed into felsic gneisses that are less dense than peridotite but more dense than continental upper crust. These more felsic rocks may rise buoyantly, undergo decompression melting and melt extraction, and be relaminated to the base of the crust. As a result of this refining and differentiation process, such relatively felsic rocks could form much of Earth's lower crust.
DS201709-2017
2017
Behn, M.D.Klein, B.Z., Jagoutz, O., Behn, M.D.Archean crustal compositions promote full mantle convection.Earth and Planetary Science Letters, Vol. 474, pp. 516-526.Mantlesubduction

Abstract: Higher mantle potential temperatures characterized the early Earth, resulting in thicker, more mafic oceanic crust entering subduction systems. This change in the composition of subducted slabs, combined with the enhanced temperature contrast between the slab and ambient mantle, would have altered the buoyancy forces driving subduction in the early Earth. Here we investigate this “compositional effect” through a combination of petrologic and thermal modeling. Specifically, we construct density profiles for sinking slabs under modern and early Earth conditions based on a range of mafic crust and mantle compositions. Slab and mantle densities are then determined from mineral assemblages calculated using the thermodynamic modeling program Perple_X along slab geotherms estimated from an analytic thermal model. Consistent with previous studies, we find that modern MORB compositions are typically less dense than the ambient mantle in the basalt barrier zone, located immediately beneath the mantle transition zone. By contrast, possible early Earth oceanic crust compositions are denser than ambient mantle at all depths down to 1000 km. This compositional effect results in slabs that would have more readily penetrated the transition zone, promoting single-layered convection and effective mantle mixing in the early Earth.
DS201809-2012
2018
Behn, M.D.Clerc, F., Behn, M.D., Parmentier, E.M., Hirth, G.Predicting rates and distribution of carbonate melting in oceanic upper mantle: implications for seismic structure and global carbon cycling.Geophysical Research Letters, doi.org/10.1029/2018GL078142Mantlemelting

Abstract: Despite support from indirect observations, the existence of a layer of carbon-rich, partially molten rock (~60 km) below oceanic crust, made possible by the presence of CO2, remains uncertain. In particular, abrupt decreases in the velocity that seismic waves propagate at depths of 40-90 and 80-180 km beneath the ocean basins remain unexplained. In this study, we test whether these seismic discontinuities can be attributed to the presence of a layer of carbon-rich melt. Melt generation occurs only where the mantle is upwelling; thus, we predict the locations of carbonate-enhanced melting using a mantle convection model and compare the resulting melt distribution with the seismic observations. We find that the shallower seismic discontinuities (at 40- to 90-km depth) are not associated with regions of predicted melting but that the deeper discontinuities (80-180 km) occur preferentially in areas of greater mantle upwelling—suggesting that these deep observations may reflect the presence of localized melt accumulation at depth. Finally, we show that carbonate melting far from mid-ocean ridges produces an additional CO2 flux previously overlooked in deep carbon cycle estimates, roughly equivalent to the flux of CO2 due to seafloor volcanism.
DS201112-0997
2011
Behnaud, M.L.Steck, L.K., Behnaud, M.L., Phillips, S., Stead, R.Tomography of crustal P and S travel times across the western United States.Journal of Geophysical Research, Vol. 116, no. B 11, B11304.United StatesGeophysics - seismics
DS201511-1841
2015
Behnia, P.Harris, J.R., Grunsky, E., Behnia, P., Corrigan, D.Dat a and knowledge-driven mineral prospectivity maps for Canada's north. (**note for Au )Ore Geology Reviews, Vol. 71, pp. 788-803.Canada, Nunavut, Melville PeninsulaGIS. IAS

Abstract: Data- and knowledge-driven techniques are used to produce regional Au prospectivity maps of a portion of Melville Peninsula, Northern Canada using geophysical and geochemical data. These basic datasets typically exist for large portions of Canada's North and are suitable for a "greenfields" exploration programme. The data-driven method involves the use of the Random Forest (RF) supervised classifier, a relatively new technique that has recently been applied to mineral potential modelling while the knowledge-driven technique makes use of weighted-index overlay, commonly used in GIS spatial modelling studies. We use the location of known Au occurrences to train the RF classifier and calculate the signature of Au occurrences as a group from non-occurrences using the basic geoscience dataset. The RF classification outperformed the knowledge-based model with respect to prediction of the known Au occurrences. The geochemical data in general were more predictive of the known Au occurrences than the geophysical data. A data-driven approach such as RF for the production of regional Au prospectivity maps is recommended provided that a sufficient number of training areas (known Au occurrences) exist.
DS200812-0096
2008
Behounkova, M.Behounkova, M., Cizkova, H.Long wavelength character of subducted slabs in the lower mantle.Earth and Planetary Science Letters, Vol. 275, 1-2, pp. 43-53.MantleGeophysics - seismics
DS200812-0097
2008
Behounkova, M.Behounkova, M., Cizkova, H.Long wavelength character of subducted slabs in the lower mantle.Earth and Planetary Science Letters, in press available,MantleSubduction
DS1992-0107
1992
Behr, H.J.Behr, H.J.Paleopermeability and fluid flow in crystalline bedrockEarth Science Reviews, Vol. 32, pp. 131-132GlobalCathodluminescence, Fluid flow
DS1994-0134
1994
Behr, H.J.Behr, H.J., Raleigh, C.B.Crustal structure of the Bohemian Massif and the West CarpathiansSpringer, 372pEuropeBook -ad, Variscan Belt
DS1994-0135
1994
Behr, S.H.Behr, S.H.Exploration targets in BotswanaPreprint, 5p.BotswanaDiamond exploration -very brief
DS201908-1770
2019
Behr, W.Behr, W.Role of major erosion events in Earth's dynamics.Nature , Vol. 570, 7759 pp. 38-39.Mantlegeomorphology

Abstract: A study provides evidence for the unconventional idea that the advent and evolution of plate tectonics on Earth were related to the rise of continents and to sediment accumulation at continental edges and in trenches.
DS201908-1771
2019
Behr, W.Behr, W.Sediment control on subduction plate speeds.Nature , Vol. 570, 7759, p. 38.Mantlesubduction

Abstract: Tectonic plate velocities predominantly result from a balance between the potential energy change of the subducting slab and viscous dissipation in the mantle, bending lithosphere, and slab-upper plate interface. A range of observations suggest that slabs may be weak, implying a more prominent role for plate interface dissipation than previously thought. The shallow thrust interface is commonly assumed to be weak due to an abundance of fluids and near-lithostatic pore fluid pressures, but little attention has been paid to the influence of the deeper, viscous interface. Here we show that the deep interface viscosity in subduction zones is strongly affected by the relative proportions of sedimentary to mafic rocks that are subducted to depth. Where sediments on the down-going plate are sparse, the deep interface is dominated by mafic lithologies that metamorphose to eclogites, which exhibit viscosities 1-2 orders of magnitude higher than the asthenospheric mantle, and reduce subduction plate speeds. In contrast, where sediments are abundant and subducted to depth, the deep interface viscosity is 1-2 orders of magnitude lower than the asthenospheric mantle, thus allowing significantly faster plate velocities. This correlation between subduction plate speed and deep sediment subduction may help explain dramatic accelerations (or decelerations) in convergence rates, such as the acceleration documented for India-Asia convergence during the mid-Cenozoic.
DS201810-2295
2018
Behr, W.M.Behr, W.M., Becker, T.W.Sediment control on subduction plate speeds.Earth and Planetary Science Letters, Vol. 502, pp. 166-173.Indiasubduction

Abstract: Tectonic plate velocities predominantly result from a balance between the potential energy change of the subducting slab and viscous dissipation in the mantle, bending lithosphere, and slab-upper plate interface. A range of observations suggest that slabs may be weak, implying a more prominent role for plate interface dissipation than previously thought. The shallow thrust interface is commonly assumed to be weak due to an abundance of fluids and near-lithostatic pore fluid pressures, but little attention has been paid to the influence of the deeper, viscous interface. Here we show that the deep interface viscosity in subduction zones is strongly affected by the relative proportions of sedimentary to mafic rocks that are subducted to depth. Where sediments on the down-going plate are sparse, the deep interface is dominated by mafic lithologies that metamorphose to eclogites, which exhibit viscosities 1-2 orders of magnitude higher than the asthenospheric mantle, and reduce subduction plate speeds. In contrast, where sediments are abundant and subducted to depth, the deep interface viscosity is 1-2 orders of magnitude lower than the asthenospheric mantle, thus allowing significantly faster plate velocities. This correlation between subduction plate speed and deep sediment subduction may help explain dramatic accelerations (or decelerations) in convergence rates, such as the acceleration documented for India-Asia convergence during the mid-Cenozoic.
DS1987-0085
1987
Behrendt, J.Cannon, W., Behrendt, J., et al.Mega half graben of the mid-continent rift zoneEos, Vol. 68, No. 44, November 3, p. 1356. abstract onlyGlobalBlank
DS1992-0744
1992
Behrendt, J.Hutchinson, D.R., Lee, M.W., Behrendt, J., Cannon, W.F., GreenVariations in the reflectivity of the Moho transition zone beneath The midcontinent Rift System of North America. Results from true amplitude GlimpcedataJournal of Geophysical Research, Vol. 97, No. B4, April 10, pp. 4721-4738MidcontinentGeophysics -seismics, Tectonics
DS1987-0042
1987
Behrendt, J.C.Behrendt, J.C., Green, A., Cannon, W.F.Crustal attentuation and associated basalt flow extrusion in the Keweenawanrift, Lake Superior from deep seismic reflectionprofilesGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p. 585. abstraGlobalTectonics
DS1988-0048
1988
Behrendt, J.C.Behrendt, J.C., Green, A.G., Cannon, W.F., Hutchinson, D.R., LeeCrustal structure of the Midcontinent rift system: results from GLIMPCE deep seismic reflection profilesGeology, Vol. 16, No. 1, January pp. 81-85GlobalTectonics, GLIMPCE.
DS200712-0064
2006
Behrens, H.Behrens, H., Gaillard, F.Geochemical aspects of melts: volatiles and redox behaviour.Elements, Vol. 2, 5, October pp. 275-280.TechnologyGeochemistry
DS201112-0665
2011
Behrens, H.Menegon, L., Nasipuri, P., Stunitz, H., Behrens, H., Ravna, E.Dry and strong quartz during deformation of the lower crust in the presence of melt.Journal of Geophysical Research, Vol. 116, B10, B10410MantleMelting
DS201809-2029
2018
Behrens, H.Gonzalez-Garcia, D., Petrelli, M., Behrens, H., Vetere, F., Fischer, L.A., Morgavi, D., Perugini, D.Diffusive exchange of trace elements between alkaline melts: implications for element fractionation and timescale estimations during magma mixing.Geochimica et Cosmochimica Acta, Vol. 233, pp. 95-114.Europe, Italyshoshonites

Abstract: The diffusive exchange of 30 trace elements (Cs, Rb, Ba, Sr, Co, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ta, V, Cr, Pb, Th, U, Zr, Hf, Sn and Nb) during the interaction of natural mafic and silicic alkaline melts was experimentally studied at conditions relevant to shallow magmatic systems. In detail, a set of 12 diffusion couple experiments have been performed between natural shoshonitic and rhyolitic melts from the Vulcano Island (Aeolian archipelago, Italy) at a temperature of 1200?°C, pressures from 50 to 500?MPa, and water contents ranging from nominally dry to ca. 2 wt.%. Concentration-distance profiles, measured by Laser Ablation ICP-MS, highlight different behaviours, and trace elements were divided into two groups: (1) elements with normal diffusion profiles (13 elements, mainly low field strength and transition elements), and (2) elements showing uphill diffusion (17 elements including Y, Zr, Nb, Pb and rare earth elements, except Eu). For the elements showing normal diffusion profiles, chemical diffusion coefficients were estimated using a concentration-dependent evaluation method, and values are given at four intermediate compositions (SiO2 equal to 58, 62, 66 and 70 wt.%, respectively). A general coupling of diffusion coefficients to silica diffusivity is observed, and variations in systematics are observed between mafic and silicic compositions. Results show that water plays a decisive role on diffusive rates in the studied conditions, producing an enhancement between 0.4 and 0.7 log units per 1 wt.% of added H2O. Particularly notable is the behaviour of the trivalent-only REEs (La to Nd and Gd to Lu), with strong uphill diffusion minima, diminishing from light to heavy REEs. Modelling of REE profiles by a modified effective binary diffusion model indicates that activity gradients induced by the SiO2 concentration contrast are responsible for their development, inducing a transient partitioning of REEs towards the shoshonitic melt. These results indicate that diffusive fractionation of trace elements is possible during magma mixing events, especially in the more silicic melts, and that the presence of water in such events can lead to enhanced chemical diffusive mixing efficiency, affecting also the estimation of mixing to eruption timescales.
DS201112-0625
2011
Behrens, M.Luget, A., Behrens, M., Herwartz, D., Pearson, D.G.Re-Os and Lu-Hf dating in Letlhakane peridotite xenoliths ( Botswana).Goldschmidt Conference 2011, abstract p.1365.Africa, BotswanaGeochronology, Magondi Belt
DS201508-0367
2015
Behrens, M.Luguet, A., Behrens, M., Pearson, D.G., Konig, S., Herwartz, D.Significance of the whole rock Re-Os ages in cryptically and modally metasomatized cratonic peridotites: constraints from HSE-Se-Te systematics.Geochimica et Cosmochimica Acta, Vol. 164, pp. 441-463.Africa, BotswanaDeposit - Letlhakane
DS1989-0099
1989
Behrmann, J.H.Behrmann, J.H., Ratschbacher, L.Archimedes revisited: a structural test of eclogite emplacement models In the Austrian AlpsTerra Nova, Vol. 1, No. 1, pp. 242-252AlpsEclogite
DS1995-2070
1995
Behrmann, J.H.Woldehaimanot, B., Behrmann, J.H.A study of metabasite and metagranite chemistry Adola region: implications evolution of East African OrogenJournal of African Earth Sciences, Vol. 21, No. 3, Oct. 1, pp. 459-476GlobalGeochemistry, Tectonics - East African Orogeny
DS201509-0425
2015
Behrmann, J.H.Ryberg, T., Haberland, C., Haberlau, T., Weber, M.H., Klaus, B., Behrmann, J.H., Jokat, W.Crustal structure of northwest Namibia: evidence for plume rift continent interaction.Geology, Vol. 43, 8,pp. 739-Africa, NamibiaPlume, rifting

Abstract: The causes for the formation of large igneous provinces and hotspot trails are still a matter of considerable dispute. Seismic tomography and other studies suggest that hot mantle material rising from the core-mantle boundary (CMB) might play a significant role in the formation of such hotspot trails. An important area to verify this concept is the South Atlantic region, with hotspot trails that spatially coincide with one of the largest low-velocity regions at the CMB, the African large low shear-wave velocity province. The Walvis Ridge started to form during the separation of the South American and African continents at ca. 130 Ma as a consequence of Gondwana breakup. Here, we present the first deep-seismic sounding images of the crustal structure from the landfall area of the Walvis Ridge at the Namibian coast to constrain processes of plume-lithosphere interaction and the formation of continental flood basalts (Paraná and Etendeka continental flood basalts) and associated intrusive rocks. Our study identified a narrow region (<100 km) of high-seismic-velocity anomalies in the middle and lower crust, which we interpret as a massive mafic intrusion into the northern Namibian continental crust. Seismic crustal reflection imaging shows a flat Moho as well as reflectors connecting the high-velocity body with shallow crustal structures that we speculate to mark potential feeder channels of the Etendeka continental flood basalt. We suggest that the observed massive but localized mafic intrusion into the lower crust results from similar-sized variations in the lithosphere (i.e., lithosphere thickness or preexisting structures).
DS1983-0130
1983
Behrmann, N.Behrmann, N.De Beers Is Expected to Bar Some from Its Diamond SalesEuropean Wall Street Journal, Nov. 18TH.GlobalInvestment
DS1983-0548
1983
Behrmann, N.Ryan, B., Behrmann, N.De Beers Lifts Prices by 3, 5%Rand Mining Man., MARCH 29TH.GlobalMarkets
DS1984-0259
1984
Behrmann, N.Emshwiller, J.R., Behrmann, N.How de Beers Revived World Diamond Cartel After Pullout by Zaire.Gan Gemstones Newsletter., 5P.GlobalBlank
DS1985-0054
1985
Behrmann, N.Behrmann, N.Diamonds Not Trader's Best Friend in Depressed AntwerpAfrican Financial Review., Feb. 5.GlobalDiamond Sales
DS1989-1427
1989
Beichman, C.A.Soifer, B.T., Beichman, C.A., Sanders, D.B.An infrared view of the universe #1American Scientist, Vol. 77, No. 1, January-February pp. 46-53. Database #GlobalGeophysics, Remote sensing -IRAS
DS200812-0098
2008
Beier, C.Beier, C., Rushmer, T., Turner, S.P.Heat sources for mantle plumes,Journal of Geophysical Research, in press available ( 45p.)MantleGeothermometry
DS1985-0055
1985
Beijing Geol. PublBeijing Geol. PublMap of Lithospheric Dynamics of China. *chiBeijing Geological Publishing, *CHI, No. 0126, $ 40.00US approxChinaMap, Tectonics
DS1994-0910
1994
Beikman, H.M.King, P.B., Beikman, H.M., et al.CD ROM digital dat a series... geology of the conterminous United States at1: 2, 250, 000 scale.United States Geological Survey (USGS) CD-ROM., 1 disc. $ 32.00United StatesMap, CD Rom -digital data
DS201902-0287
2019
Beinlich, A.Kourim, F., Beinlich, A., Wang, K.L., Michibayashi, K., O'Reilly, S.Y., Pearson, N.J.Feedback of mantle metasomatism on olivine micro-fabric and seismic properties of the deep lithosphere. Lithos, Vol. 328, pp. 43-57.Asia, Taiwanmetasomatism

Abstract: The interaction of hydrous fluids and melts with dry rocks of the lithospheric mantle inevitably modifies their viscoelastic and chemical properties due to the formation of compositionally distinct secondary phases. In addition, melt percolation and the associated metasomatic alteration of mantle rocks may also facilitate modification of the pre-existing rock texture and olivine crystallographic preferred orientation (CPO) and thus seismic properties. Here we explore the relationship between mantle metasomatism, deformation and seismic anisotropy using subduction-related mantle xenoliths from the Penghu Islands, western Taiwan. The investigated xenoliths have equilibrated at upper lithospheric mantle conditions (879?°C to 1127?°C) based on pyroxene geothermometry and show distinct variations in clinopyroxene chemical composition, texture and olivine CPO allowing for the classification of two distinct groups. Group 1 xenoliths contain rare earth element (REE) depleted clinopyroxene, show a porphyroclastic texture and olivine grains are mostly characterized by [100]-axial pattern symmetries. In contrast, REE-enriched clinopyroxene from Group 2 xenoliths occur in a fine-grained equigranular texture and coexisting olivine frequently displays [010]-axial pattern symmetries. The clinopyroxene compositions are indicative of cryptic and modal to stealth metasomatic alteration of Group 1 and Group 2 xenoliths, respectively. Furthermore, the observed olivine [100]-axial pattern of Group 1 xenoliths reflects deformation by dislocation creep at high temperature, low pressure and dry conditions, whereas olivine [010]-axial patterns of Group 2 xenoliths imply activation of olivine [001] glide planes along preferentially wet (010) grain boundaries. This correlation indicates that the variation in olivine CPO symmetry from [100]- to [010]-axial pattern in Penghu xenoliths results from deformation and intra-crystalline recovery by subgrain rotation during metasomatic alteration induced by melt percolation. The microstructural observations and olivine CPO combined with petrological and geochemical data suggest that Group 1 xenoliths preserve microstructural and chemical characteristics of an old, probably Proterozoic lithosphere, while Group 2 xenoliths record localized Miocene deformation associated with wall-rock heating and metasomatism related to melt circulation. Furthermore, the observed transition of olivine CPO from [100]-axial pattern to [010]-axial pattern by deformation in the presence of variable melt fractions and associated metasomatic alteration can be inferred to modify the physical properties of mantle rocks.
DS201905-1052
2019
Beinlich, A.Kourim, F., Beinlich, A., Wang, K-L., Michibayashi, K., O'Reilly, S.Y., Pearson, N.J.Feedback of mantle metasomatism on olivine micro-fabric and seismic properties of the deep lithosphere.Lithos, Vol. 328-329, pp. 43-57.Asia, Taiwan, Penghu Islandsmetasomatism

Abstract: The interaction of hydrous fluids and melts with dry rocks of the lithospheric mantle inevitably modifies their viscoelastic and chemical properties due to the formation of compositionally distinct secondary phases. In addition, melt percolation and the associated metasomatic alteration of mantle rocks may also facilitate modification of the pre-existing rock texture and olivine crystallographic preferred orientation (CPO) and thus seismic properties. Here we explore the relationship between mantle metasomatism, deformation and seismic anisotropy using subduction-related mantle xenoliths from the Penghu Islands, western Taiwan. The investigated xenoliths have equilibrated at upper lithospheric mantle conditions (879?°C to 1127?°C) based on pyroxene geothermometry and show distinct variations in clinopyroxene chemical composition, texture and olivine CPO allowing for the classification of two distinct groups. Group 1 xenoliths contain rare earth element (REE) depleted clinopyroxene, show a porphyroclastic texture and olivine grains are mostly characterized by [100]-axial pattern symmetries. In contrast, REE-enriched clinopyroxene from Group 2 xenoliths occur in a fine-grained equigranular texture and coexisting olivine frequently displays [010]-axial pattern symmetries. The clinopyroxene compositions are indicative of cryptic and modal to stealth metasomatic alteration of Group 1 and Group 2 xenoliths, respectively. Furthermore, the observed olivine [100]-axial pattern of Group 1 xenoliths reflects deformation by dislocation creep at high temperature, low pressure and dry conditions, whereas olivine [010]-axial patterns of Group 2 xenoliths imply activation of olivine [001] glide planes along preferentially wet (010) grain boundaries. This correlation indicates that the variation in olivine CPO symmetry from [100]- to [010]-axial pattern in Penghu xenoliths results from deformation and intra-crystalline recovery by subgrain rotation during metasomatic alteration induced by melt percolation. The microstructural observations and olivine CPO combined with petrological and geochemical data suggest that Group 1 xenoliths preserve microstructural and chemical characteristics of an old, probably Proterozoic lithosphere, while Group 2 xenoliths record localized Miocene deformation associated with wall-rock heating and metasomatism related to melt circulation. Furthermore, the observed transition of olivine CPO from [100]-axial pattern to [010]-axial pattern by deformation in the presence of variable melt fractions and associated metasomatic alteration can be inferred to modify the physical properties of mantle rocks.
DS1996-0206
1996
Beirlant, J.Caers, J., Vynckier, P., Beirlant, J., Rombouts, L.Extreme value analysis of diamond size distributionsMathematical Geology, Vol. 28, No. 1, pp. 25-43.GuineaGeostatistics, Diamond distribution
DS1950-0315
1957
Beit, A.Beit, A., Lockhart, J.G.The Will and the WayNew York: Longmans, Green And Co., 106P.South AfricaKimberley, Biography
DS2003-0092
2003
Bejina, F.Bejina, F., Jaoul, O., Liebermann, R.C.Diffusion in minerals at high pressure: a reviewPhysics of the Earth and Planetary Interiors, Vol. 139, 1-2, Sept. 30, pp. 3-20.GlobalPetrology, experimental, UHP
DS200412-0126
2003
Bejina, F.Bejina, F., Jaoul, O., Liebermann, R.C.Diffusion in minerals at high pressure: a review.Physics of the Earth and Planetary Interiors, Vol. 139, 1-2, Sept. 30, pp. 3-20.TechnologyPetrology, experimental, UHP
DS201912-2803
2019
Bekaert, D.V.Marty, B., Bekaert, D.V., Broadley, Jaupart, C.Geochemical evidence for high volatile fluxes from the mantle at the end of the Archean. (water, carbon dioxide, nitrogen and halogens)Nature, Vol. 575, pp. 485-488.Mantlemelting, convection

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

Abstract: Nitrogen is the main constituent of the Earth’s atmosphere, but its provenance in the Earth’s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth’s accretion versus that subducted from the Earth’s surface is unclear1,2,3,4,5,6. Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare 15N15N isotopologue of N2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle d15N (the fractional difference in 15N/14N from air), N2/36Ar and N2/3He. Our results show that negative d15N values observed in gases, previously regarded as indicating a mantle origin for nitrogen7,8,9,10, in fact represent dominantly air-derived N2 that experienced 15N/14N fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the 15N15N data allow extrapolations that characterize mantle endmember d15N, N2/36Ar and N2/3He values. We show that the Eifel region has slightly increased d15N and N2/36Ar values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts11, consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has d15N values substantially greater than that of the convective mantle, resembling surface components12,13,14,15, its N2/36Ar and N2/3He ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume d15N values may both be dominantly primordial features.
DS1984-0142
1984
Bekesha, S.N.Bartoshinskiy, Z.V., Bekesha, S.N., Bilenko, YU.M., Vinnichenko, T.G.Distribution of natural diamonds based on their intensity ofluminescence.(Russian)Mineral. Sborn. (L'Vov), (Russian), Vol. 38, No. 2, pp. 25-27RussiaDiamond Morphology
DS1986-0056
1986
Bekesha, S.N.Bartoshinskiy, Z.V., Bekesha, S.N., Vinnichenko, T.G.Types of photoluminesence spectra of Yakutia diamond. (Russian)Mineral. Zhurnal., (Russian), Vol. 40, No. 1, pp. 32-38RussiaDiamond morphology, Luminesence
DS1986-0057
1986
Bekesha, S.N.Bartoshinskiy, Z.V., Bekesha, S.N., Vinnichenko, T.G., PidzyrailoTypes of photoluminescence spectra of diamonds of Yakutia.(Russian)Mineral. Sbov. (Lvov), (Russian), Vol. 40, No. 1, pp. 32-38RussiaSpectroscopy
DS1987-0036
1987
Bekesha, S.N.Bartoshinskii, Z.V., Matyash, I.V., Mazykin, V.V., Bekesha, S.N.Major nitrogen paramagnetic centers in diamonds from placers of northeastern Siberian PlatformMineral. Zhurn., (Russian), Vol. 9, No. 3, pp. 87-89RussiaBlank
DS1988-0044
1988
Bekesha, S.N.Bartoshinskii, Z.V., Bekesha, S.N., Vinnichenko, T.G.Relation between the degree of preservation Of kimberlite hosted diamond sand some opticalparameters.(Russian)Mineral. Sbornik (L'Vov), (Russian), Vol. 42, No. 1, pp. 8-13RussiaDiamond morphology
DS1989-0087
1989
Bekesha, S.N.Bartoshinskiy, Z.V., Bekesha, S.N., Vinnicehnko, T.G., Zudin, N.G.Gas admixtures in diamonds and garnets from kimberlites of the Daldyn-Alakit region in Yakutia.(Russian)Mineralogicheskiy Sbornik, (Russian), Vol. 43, No. 2, pp. 83-86Russia, YakutiaMineral chemistry
DS1990-0172
1990
Bekesha, S.N.Bartoshinskiy, Z.V., Bekesha, S.N., Verzhak, V.V., Vinnichenko, T.G.Non x-ray luminescence kimberlite diamonds.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 2, pp. 15-19RussiaDiamond morphology, Spectroscopy
DS1990-0173
1990
Bekesha, S.N.Bartoshinsky, Z.V., Bekesha, S.N., et al.Luminesence kinetics of N3 centers of natural diamond.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 6, December pp. 85-87RussiaMineralogy, Diamond luminesence
DS1992-0094
1992
Bekesha, S.N.Bartoshinskiy, Z.V., Bekesha, S.N., Vinnicehnko, T.G.Photoluminescence sprecta of diamond from kimberlite pipes of the northern European Platform**RusL'vov University Of, (russian), Vol. 14, No. 3, pp. 25-30Russia, YakutiaArkhangelskgeol, Ore microscopy
DS1995-0114
1995
Bekesha, S.N.Bartoshinsky, Z.V., Bekesha, S.N., Vinnichenko, Zudin etGas impurities in diamonds and garnets from kimberlites of the Daldyn-Alakit region, Yakutia.Proceedings of the Sixth International Kimberlite Conference Almazy Rossii Sakha abstract, p. 20-22.Russia, YakutiaDiamond inclusions, Deposit -Sytykan, Udachnaya
DS201906-1336
2019
Bekhtenova, A.Podborodnikov, I.V., Shatskiy, A., Arefiev, A.V., Bekhtenova, A.New data on the system Na2CO3-CaCO3-MgCO3 at 6 Gpa with implications to the composition and stability of carbonatite melts at the base of continental lithosphere.Chemical Geology, Vol. 515, pp. 50-60.Russiadeposit - Udachnaya-East

Abstract: Subsolidus and melting phase relationships in the system Na2CO3-CaCO3-MgCO3 have been studied at 6?GPa and 900-1250?°C using a Kawai-type multianvil press. At 900 and 1000?°C, the system has four intermediate compounds: Na2Ca4(CO3)5 burbankite, Na2Ca3(CO3)4, Na4Ca(CO3)3, and Na2Mg(CO3)2 eitelite. The Na-Ca compounds dissolve noticeable amounts of Mg component, whereas eitelite dissolves a few percents of Ca component: Na2(Ca=0.91Mg=0.09)4(CO3)5, Na2(Ca=0.94Mg=0.06)3(CO3)4, Na4(Ca=0.67Mg=0.33)(CO3)3, and Na2(Mg=.93Ca=0.07)(CO3)2. At 1050?°C, the system is complicated by an appearance of dolomite. Na-Ca burbankite decomposes at 1075?±?25?°C to aragonite plus Na2Ca3(CO3)4. Na4Ca(CO3)3 and eitelite disappear via congruent melting between 1200 and 1250?°C. Na2Ca3(CO3)4 remains stable through the whole studied temperature range. The liquidus projection of the studied ternary system has eight primary solidification phase regions for magnesite, dolomite, calcite-dolomite solid solutions, aragonite, Na2Ca3(CO3)4, Na4Ca(CO3)3, and Na2CO3 solid solutions. The system has five ternary peritectic reaction points and one minimum on the liquidus at 1050?°C and 48Na2CO3•52(Ca0.75Mg0.25)CO3. The minimum point resembles a eutectic controlled by a four-phase reaction, by which a liquid transforms into three solid phases upon cooling: Na2(Ca0.94Mg0.06)3(CO3)4, Na4(Ca0.67Mg0.33)(CO3)3, and Na2(Mg0.93Ca0.07)(CO3)2 eitelite. Since at 6?GPa, the system has a single eutectic, there is no thermal barrier preventing continuous liquid fractionation from alkali-poor toward Na-rich dolomitic compositions. Cooling of the Na-Ca-Mg carbonatite melt from 1400 to 1100?°C within the lherzolite substrate will be accompanied by magnesite crystallization and wehrlitization keeping calcium number of the melt at 40 and shifting the Na2CO3 content to =40?mol%. In the case of the eclogitic wall rock, the cooling will be accompanied by dolomite crystallization keeping calcium number of the melt at 60-65 and shifting the Na2CO3 content to =30?mol%.
DS202009-1660
2020
Bekhtenova, A.Shatskiy, A., Bekhtenova, A., Podborodnikov, I.V., Arefiev, A.V., Litasov, K.D.Metasomatic interaction of the eutectic Na- and K-bearing carbonate melts with natural garnet lherzolite at 6 Gpa and 1100-1200 C: toward carbonatite melt composition in SCLM.Lithos, Vol. 374-375, 17p. PdfMantlemetasomatism

Abstract: The range of carbonatite melts in equilibrium with the subcontinental lithospheric mantle (SCLM) under geothermal conditions is limited by alkali-rich near-eutectic compositions. Therefore, here we employed eutectic Na/K-Ca-Mg-Fe carbonate mixtures to model the interaction of a metasomatic carbonatite melt with natural garnet lherzolite. The experiments were performed at 1100 and 1200 °C and 6 GPa in graphite capsules using a multianvil press. The run duration was 111 and 86 h, respectively. To verify achieving an equilibrium, a synthetic mixture identical to natural lherzolite was also employed. We have found that both Na- and K-bearing carbonatite melts cause wehrlitization accompanying by the elimination of orthopyroxene and an increase of CaO in garnet at a constant Cr2O3. Interaction with the K-carbonatite melt alters clinopyroxene composition toward lower Na2O (0.2-0.3 wt%), and higher K2O (0.5-1.0 wt%), whereas the Na-carbonatite melt revealed the opposite effect. The resulting melts have a following approximate composition [40(Na, K)2CO3·60Ca0.5Mg0.4Fe0.1CO2 + 0.6-1.4 wt% SiO2] displaying a decrease in Ca# at a nearly constant alkali content relative to the initial composition, where Ca# = 100·Ca/(Ca + Mg + Fe). We have also found that alkali-poor (= 20 mol% (Na, K)2CO3) carbonate mixtures do not melt completely but yield magnesite and alkali- and Ca-rich melts like those in the systems with eutectic mixtures. Under SCLM P-T conditions the range of carbonatite melt compositions is restricted by the full melting field of alkali-rich carbonates in the corresponding Na/K-Ca-Mg carbonate systems. Infiltration of less alkaline higher-temperature carbonatite melt in SCLM and its subsequent cooling to the ambient mantle temperature, 1100-1200 °C at 6 GPa, should cause crystallization of magnesite and shift the melt composition to [30(Na, K)2CO3·70Ca0.6Mg0.3Fe0.1CO3]. Owing to its high Ca#, this melt is not stable in equilibrium with orthopyroxene yielding its disappearance by CaMg exchange reaction producing clinopyroxene, magnesite, and shifting the melt composition toward higher alkali content. The melts containing 40-45 mol% of alkaline carbonates have no limitation in Ca# because the corresponding binary NaMg and KMg carbonate eutectics are located near 1200 °C. Therefore, these melts can achieve Ca# = 30-40 and, be in equilibrium with garnet lherzolites and harzburgites under the geothermal condition of SCLM. Considering the present results and previous experimental data the following ranges of carbonatite melt compositions can be expected in equilibrium with garnet peridotites at the base of SCLM: Ca# < 30 and > 30 mol% (K, Na)2CO3 in equilibrium with harzburgite; Ca# 30-40, >25 mol% (K, Na)2CO3 in equilibrium with lherzolite; and Ca# 40-60 and >20 mol% (K, Na)2CO3 in equilibrium with wehrlite.
DS202012-2250
2020
Bekhtenova, A.Shatskiy, A., Bekhtenova, A., Podbororodnikov, I.V., Arefiev, A.V.Carbonate melt interaction with natural eclogite at 6 Gpa and 1100-1200 C Implcations for metasomatic melt composition in subcontinental lithospheric mantle.Chemical Geology, Vol. 558, 119915, 15p. PdfMantlecarbonatite

Abstract: Compositional ranges of carbonate melts stable under P-T conditions corresponding to the base of subcontinental lithospheric mantle (SCLM) are limited by alkali-rich near-eutectic compositions. In the present work, we investigated the interaction of such melts with the natural eclogite of Group A. It was found that the interaction is accompanied by decreasing Ca# in the melt (L) and increasing Ca# in garnet (Grt) according to the reaction: 3CaCO3 (L) + Mg3Al2Si3O12 (Grt) = 3MgCO3 (Mgs and/or L) + Ca3Al2Si3O12 (Grt), where Mgs is magnesite. The interaction with the Na-Ca-Mg-Fe carbonate melt increases amount of jadeite component in clinopyroxene (Cpx) consuming Al2O3 from garnet and Na2O from the melt according to the reaction: Na2CO3 (L) + CaCO3 (L) + 2Mg3Al2Si3O12 (Grt) + 2CaMgSi2O6 (Cpx) = 2NaAlSi2O6 (Cpx) + Ca3Al2Si3O12 (Grt) + 2MgCO3 (Mgs, L) + 3Mg2SiO4 (Ol). As a result, garnet and omphacite compositions evolve from eclogite Group A to eclogite Group B. A byproduct of the reaction is olivine (Ol), which may explain the formation of inclusions of “mixed” eclogite (garnet + omphacite) and peridotite (olivine) paragenesis in lithospheric diamonds. The interaction with the K-Ca-Mg-Fe carbonate melt increases the K2O content in clinopyroxene to 0.5-1.2 wt%, while the Na2O content lowers to 0.3 wt%. The following range of carbonatite melt compositions can be in equilibrium with eclogite at the base of SCLM (1100-1200 °C and 6 GPa): 18(Na0.97K0.03)2CO3·82(Ca0.63Mg0.30Fe0.07)CO2-42(Na0.97K0.03)2CO3·58(Ca0.46Mg0.45Fe0.09)CO2. Our results also suggest that the partial melting of ‘dry’ carbonated eclogite, if any, at 1100 °C and 6 GPa yields the formation of a carbonate melt with the following composition (mol%) 25(Na0.96K0.04)2CO3·75(Ca0.64Mg0.31Fe0.05)CO2, corresponding to 18-27 wt% Na2O in the melt on a volatile-free basis.
DS1990-0183
1990
Bekhtol, D.A.F.Bekhtol, D.A.F., Semenov, D.F.Metabasites and ultrabasites of the Susunay Range, Sakhalin Island.(Russian)Tikhookeanskaya Geol. (Russian), Vol. 1990, No. 1, pp. 121-126RussiaPetrology, Diamond mentioned
DS2000-0074
2000
Bekker, A.Bekker, A.Response of the exosphere to the 2.48- 2-45 GA superplume eventGeological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-315.Canada, Wyoming, South AfricaCraton - Superior, Wyoming, Kaapvaal, Continents
DS2003-0093
2003
Bekker, A.Bekker, A., Eriksson, K.A.A Paleoproterozoic drowned carbonate platform on the southeastern margin of thePrecambrian Research, Vol. 120, No. 3-4, pp. 327-64.Wyoming, ColoradoStratigraphy - not specific to diamonds
DS1992-0108
1992
Bekker, A.Y.Bekker, Y.R., Bekker, A.Y.The stages of development of the Russian platform in Precambrian timeGeological Society of America (GSA) Abstracts with programs, 1992 Annual, Vol. 24, No. 7, abstract p. A115RussiaCraton, Tectonics
DS201605-0809
2016
Bekker, E.Bekker, E.DMC basics - a hollistic view.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 275-286.Economics
DS201906-1315
2019
Bekker, T.B.Litasov, K.D., Kagi, H., Voropaev, S.A., Hirata, T., Ohfuji, H., Ishibashi., Makino, Y., Bekker, T.B., Sevastyanov, V.S., Afanasiev,V.P., Pokhilenko, N.P.Comparison of enigmatic diamonds from the Tolbachik arc volcano ( Kamchatka) and Tibetan ophiolites: assessing the role of contamination by synthetic materials. Gondwana Research, in press available 38p.Russia, Asia, Tibetdeposit - Tolbachik

Abstract: The enigmatic appearance of cuboctahedral diamonds in ophiolitic and arc volcanic rocks with morphology and infrared characteristics similar to synthetic diamonds that were grown from metal solvent requires a critical reappraisal. We have studied 15 diamond crystals and fragments from Tolbachik volcano lava flows, using Fourier transform infrared spectrometry (FTIR), transmission electron microscopy (TEM), synchrotron X-ray fluorescence (SRXRF) and laser ablation inductively coupled plasma mass-spectrometry (LA-ICP-MS). FTIR spectra of Tolbachik diamonds correspond to typical type Ib patterns of synthetic diamonds. In TEM films prepared using focused ion beam technique, we find Mn-Ni and Mn-Si inclusions in Tolbachik diamonds. SRXRF spectra indicate the presence of Fe-Ni and Fe-Ni-Mn inclusions with Cr, Ti, Cu, and Zn impurities. LA-ICP-MS data show variable but significantly elevated concentrations of Mn, Fe, Ni, and Cu reaching up to 70?ppm. These transition metal concentration levels are comparable with those determined by LA-ICP-MS for similar diamonds from Tibetan ophiolites. Mn-Ni (+Fe) solvent was widely used to produce industrial synthetic diamonds in the former USSR and Russia with very similar proportions of these metals. Hence, it appears highly probable that the cuboctahedral diamonds recovered from Kamchatka arc volcanic rocks represent contamination and are likely derived from drilling tools or other hard instruments. Kinetic data on diamond dissolution in basaltic magma or in fluid phase demonstrate that diamond does not form under the pressures and temperature conditions prevalent within the magmatic system beneath the modern-day Klyuchevskoy group of arc volcanoes. We also considered reference data for inclusions in ophiolitic diamonds and compared them with the composition of solvent used in industrial diamond synthesis in China. The similar inclusion chemistry close to Ni70Mn25Co5 for ophiolitic and synthetic Chinese diamonds scrutinized here suggests that most diamonds recovered from Tibetan and other ophiolites are not natural but instead have a synthetic origin. In order to mitigate further dubious reports of diamonds from unconventional tectonic settings and source rocks, we propose a set of discrimination criteria to better distinguish natural cuboctahedral diamonds from those produced synthetically in industrial environments and found as contaminants in mantle- and crust-derived rocks.
DS1992-0108
1992
Bekker, Y.R.Bekker, Y.R., Bekker, A.Y.The stages of development of the Russian platform in Precambrian timeGeological Society of America (GSA) Abstracts with programs, 1992 Annual, Vol. 24, No. 7, abstract p. A115RussiaCraton, Tectonics
DS1988-0369
1988
Bekman, I.K.Konev, A.A., Bekman, I.K., Vorobiev, E.I., Piskunova, L.F.Leucitic lamproites of the Molbo River.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 299, No. 3, pp. 707-710RussiaBlank
DS1995-0132
1995
Bekmukhametov, A.E.Bekmukhametova, Z.A., Bekmukhametov, A.E.Petrology of carbon fractionization and geodynamic of it's metamorphis mduring the diamonds formation.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 47-49.RussiaKakshetau Massif, Kirgiz Range, Mugodgary, Mamyt Ebeta, Kempirisai
DS1995-0132
1995
Bekmukhametova, Z.A.Bekmukhametova, Z.A., Bekmukhametov, A.E.Petrology of carbon fractionization and geodynamic of it's metamorphis mduring the diamonds formation.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 47-49.RussiaKakshetau Massif, Kirgiz Range, Mugodgary, Mamyt Ebeta, Kempirisai
DS201112-0858
2011
Bekoa, A.Reusch, A.M., Nyblade, A.A., Tibi, R., Wiens, D.A., Shore, P.J., Bekoa, A., Tabod, C.T., Mnange, J.M.Mantle transition zone thickness beneath Cameroon: evidence for an upper mantle origin for the Cameroon Volcanic Line.Geophysical Journal International, Vol. 187, 3, pp.1146-1150.Africa, CameroonMantle zone
DS201012-0721
2010
Bekrenev, Zaitsev.IzbekovSmelov, A.P., Andreev, Altukhova, Babushkin, Bekrenev, Zaitsev.Izbekov, Koroleva, Mishmin, Okrugin, OleinkovKimberlites of the Manchary pipe: a new kimberlite field in central Yakutia.Russian Geology and Geophysics, Vol. 51, pp. 121-126.Russia, YakutiaDeposit - Manchary
DS201505-0249
2015
Belakoviskiy, D.I.Belogub, E.V., Krivovichev, S.V., Pekov, I.V., Kuznetsov, A.M., Yapaskurt, V.O., Kitlyarov, V.A., Chukanov, N.V., Belakoviskiy, D.I.Nickelpicromerite, K2Ni(SO4)2*6H2O, a new picromerite group mineral from Slyudorudnik, South Urals, Russia.Mineralogy and Petrology, Vol. 109, 2, pp. 143-152.Russia, UralsMineralogy

Abstract: A new picromerite-group mineral, nickelpicromerite, K2Ni(SO4)2 - 6H2O (IMA 2012-053), was found at the Vein #169 of the Ufaley quartz deposit, near the town of Slyudorudnik, Kyshtym District, Chelyabinsk area, South Urals, Russia. It is a supergene mineral that occurs, with gypsum and goethite, in the fractures of slightly weathered actinolite-talc schist containing partially vermiculitized biotite and partially altered sulfides: pyrrhotite, pentlandite, millerite, pyrite and marcasite. Nickelpicromerite forms equant to short prismatic or tabular crystals up to 0.07 mm in size and anhedral grains up to 0.5 mm across, their clusters or crusts up to 1 mm. Nickelpicromerite is light greenish blue. Lustre is vitreous. Mohs hardness is 2-2½. Cleavage is distinct, parallel to {10-2}. Dmeas is 2.20(2), Dcalc is 2.22 g cm-3. Nickelpicromerite is optically biaxial (+), a = 1.486(2), ß = 1.489(2), ? = 1.494(2), 2Vmeas =75(10)°, 2Vcalc =76°. The chemical composition (wt.%, electron-microprobe data) is: K2O 20.93, MgO 0.38, FeO 0.07, NiO 16.76, SO3 37.20, H2O (calc.) 24.66, total 100.00. The empirical formula, calculated based on 14 O, is: K1.93Mg0.04Ni0.98S2.02O8.05(H2O)5.95. Nickelpicromerite is monoclinic, P21/c, a = 6.1310(7), b = 12.1863(14), c = 9.0076(10) Å, ß = 105.045(2)°, V = 649.9(1) Å3, Z = 2. Eight strongest reflections of the powder XRD pattern are [d,Å-I(hkl)]: 5.386--34(110); 4.312-46(002); 4.240-33(120); 4.085--100(012, 10-2); 3.685-85(031), 3.041-45(040, 112), 2.808-31(013, 20-2, 122), 2.368-34(13-3, 21-3, 033). Nickelpicromerite (single-crystal X-ray data, R = 0.028) is isostructural to other picromerite-group minerals and synthetic Tutton’s salts. Its crystal structure consists of [Ni(H2O)6]2+ octahedra linked to (SO4)2- tetrahedra via hydrogen bonds. K+ cations are coordinated by eight anions. Nickelpicromerite is the product of alteration of primary sulfide minerals and the reaction of the acid Ni-sulfate solutions with biotite.
DS201609-1729
2016
Belakovskiy, D.I.Lykova, I.S., Pekov, I.V., Chukanov, N.V., Belakovskiy, D.I., Yapaskurt, V.O., Zubkova, N.V., Britvin, S.N., Giester, G.Calciomurmanite a new mineral from the Lovozero and Khibiny alkaline complexes, Kola Peninsula.European Journal of Minerlogy, in press avaialbe 15p.RussiaMineralogy
DS201904-0766
2018
Belakovskiy, D.I.Pekov, I.V., Zubkova, N.V., Yapaskurt, V.O., Lykova, I.S., Chukanov, N.V., Belakovskiy, D.I., Britvin, S.N., Turchkova, A.G., Pushcharovsky, D.Y.Alexhomyakovite, K6(Ca2Na) (CO3)5CI.6h2O, a new mineral from the Khibiny alkaline complex, Kola Peninsula, Russia.European Journal of Mineralogy, Vol. 31, pp. 13-143.Russia, Kola Peninsuladeposit - Khibiny

Abstract: The new mineral alexkhomyakovite K6(Ca2Na)(CO3)5Cl·6H2O (IMA2015-013) occurs in a peralkaline pegmatite at Mt. Koashva, Khibiny alkaline complex, Kola peninsula, Russia. It is a hydrothermal mineral associated with villiaumite, natrite, potassic feldspar, pectolite, sodalite, biotite, lamprophyllite, titanite, fluorapatite, wadeite, burbankite, rasvumite, djerfisherite, molybdenite and an incompletely characterized Na-Ca silicate. Alexkhomyakovite occurs as equant grains up to 0.2 mm, veinlets up to 3 cm long and up to 1 mm thick and fine-grained aggregates replacing delhayelite. Alexkhomyakovite is transparent to translucent, colourless, white or grey, with vitreous to greasy lustre. It is brittle, the Mohs hardness is ca. 3. No cleavage was observed, the fracture is uneven. D meas = 2.25(1), D calc = 2.196 g cm-3. Alexkhomyakovite is optically uniaxial (-), ? = 1.543(2), e = 1.476(2). The infrared spectrum is reported. The chemical composition [wt%, electron microprobe data, CO2 and H2O contents calculated for 5 (CO3) and 6 (H2O) per formula unit (pfu), respectively] is: Na2O 4.09, K2O 35.72, CaO 14.92, MnO 0.01, FeO 0.02, SO3 0.11, Cl 4.32, CO2 28.28, H2O 13.90, -O=Cl -0.98, total 100.39. The empirical formula calculated on the basis of 9 metal cations pfu is K5.90Ca2.07Na1.03(CO3)5(SO4)0.01O0.05Cl0.95·6H2O. The numbers of CO3 groups and H2O molecules are based on structure data. Alexkhomyakovite is hexagonal, P63/mcm, a = 9.2691(2), c = 15.8419(4) Å, V = 1178.72(5) Å3 and Z = 2. The strongest reflections of the powder X-ray diffraction pattern [d Å(I)(hkl)] are: 7.96(27)(002), 3.486(35)(113), 3.011(100)(114), 2.977(32)(211), 2.676(36)(300), 2.626(42)(213, 115), 2.206(26)(311) and 1.982(17)(008). The crystal structure (solved from single-crystal X-ray diffraction data, R = 0.0578) is unique. It is based on (001) heteropolyhedral layers of pentagonal bipyramids (Ca,Na)O5(H2O)2 interconnected via carbonate groups of two types, edge-sharing ones and vertex-sharing ones. Ca and Na are disordered. Ten-fold coordinated K cations centre KO6Cl(H2O)3 polyhedra on either side of the heteropolyhedral layer. A third type of carbonate group and Cl occupy the interlayer. The mineral is named in honour of the outstanding Russian mineralogist Alexander Petrovich Khomyakov (1933-2012).
DS202011-2036
2020
Belakovskiy, D.I.Chukanov, N.V., Aksenov, S.M., Pekov, I.V., Belakovskiy, D.I., Vozchikova, S.A., Britvin, S.N.Sergevanite, new eudialyte group mineral from the Lovozero alkaline massif, Kola Peninsula.The Canadian Mineralogist, Vol. 58, pp. 421-436.Russia, Kola Peninsuladeposit - Lovozero

Abstract: The new eudialyte-group mineral sergevanite, ideally Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3•H2O, was discovered in highly agpaitic foyaite from the Karnasurt Mountain, Lovozero alkaline massif, Kola Peninsula, Russia. The associated minerals are microcline, albite, nepheline, arfvedsonite, aegirine, lamprophyllite, fluorapatite, steenstrupine-(Ce), ilmenite, and sphalerite. Sergevanite forms yellow to orange-yellow anhedral grains up to 1.5 mm across and the outer zones of some grains of associated eudialyte. Its luster is vitreous, and the streak is white. No cleavage is observed. The Mohs' hardness is 5. Density measured by equilibration in heavy liquids is 2.90(1) g/cm3. Calculated density is equal to 2.906 g/cm3. Sergevanite is nonpleochroic, optically uniaxial, positive, with ? = 1.604(2) and e = 1.607(2) (? = 589 nm). The infrared spectrum is given. The chemical composition of sergevanite is (wt.%; electron microprobe, H2O determined by HCN analysis): Na2O 13.69, K2O 1.40, CaO 7.66, La2O3 0.90, Ce2O3 1.41, Pr2O3 0.33, Nd2O3 0.64, Sm2O3 0.14, MnO 4.15, FeO 1.34, TiO2 1.19, ZrO2 10.67, HfO2 0.29, Nb2O5 1.63, SiO2 49.61, SO3 0.77, Cl 0.23, H2O 4.22, -O=Cl -0.05, total 100.22. The empirical formula (based on 25.5 Si atoms pfu, in accordance with structural data) is H14.46Na13.64K0.92Ca4.22Ce0.27La0.17Nd0.12Pr0.06Sm0.02Mn1.81Fe2+0.58Ti0.46Zr2.67Hf0.04Nb0.38Si25.5S0.30Cl0.20O81.35. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is trigonal, space group R3, with a = 14.2179(1) Å, c = 30.3492(3) Å, V = 5313.11(7) Å3, and Z = 3. In the structure of sergevanite, Ca and Mn are ordered in the six-membered ring of octahedra (at the sites M11 and M12), and Na dominates over Fe2+ at the M2 site. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 7.12 (70) (110), 5.711 (43) (202), 4.321 (72) (205), 3.806 (39) (033), 3.551 (39) (220, 027), 3.398 (39) (313), 2.978 (95) (?forumla?), 2.855 (100) (404). Sergevanite is named after the Sergevan' River, which is near the discovery locality.
DS201709-1961
2017
Beland, C.M.J.Beland, C.M.J., William-Jones, A.E.The nature and origin of REE mineralization in the Ashram deposit, Eldor carbonatite complex, Quebec, CanadaGoldschmidt Conference, abstract 1p.Canada, Quebeccarbonatite, Eldor

Abstract: A growing number of studies have suggested that hydrothermal remobilization is crucial for the formation of carbonatite-hosted rare earth element (REE) deposits [1-3]. The Ashram REE deposit, hosted by the Paleoproterozoic Eldor Carbonatite Complex [4], is an example of a REE deposit formed mainly due to hydrothermal processes in magnesio- and ferro-carbonatite. The REE minerals in the Ashram deposit, monazite-(Ce), bastnäsite-(Ce), xenotime- (Y) and minor aeschynite-(Y), are secondary, and were precipitated from hydrothermal fluids. They occur mainly as disseminations, in breccia matrices and veins, and as vug fillings. Hydrothermal apatite and fluorite are also present in appreciable quantities in REE-mineralized zones. Monazite- (Ce) was the earliest REE mineral to form, and was followed by xenotime-(Y) and bastnäsite-(Ce). The compositions of the main REE minerals vary with location in the deposit, particularly in respect to their Nd2O3 and ThO2 contents. Two generations of monazite-(Ce) have been distinguished on the basis of their Nd content. Early, low-Nd monazite-(Ce) formed by replacing apatite through the substitution of 3REE3+ for 5Ca2+ + F- ; low-Nd apatite is LREE-enriched compared to apatite. In contrast, the later high-Nd generation, which has a chondrite-normalized REE profile almost perfectly parallel to that of the apatite, is interpreted to have formed by dissolving the Ca2+ and F- of the apatite and reconstituting the REE and phosphate as monazite-(Ce): Ca4.94REE0.060(PO4)3F = 0.060REEPO4 + F- + 4.94Ca2+ + 2.94PO4 3- Bastnäsite-(Ce) developed as a replacement of monazite- (Ce) through ligand exchange (F- and CO3 2- for PO4 3- ), while preserving the original REE chemistry. A combination of magmatic zone-refinement and hydrothermal remobilization, involving a chloride-bearing fluid, contributed to the formation of a carbonatite-hosted REE deposit.
DS1989-0100
1989
Beland, S.Beland, S.Rapport d'evaluation de la propriete MontvielQuebec Department of Mines, GM 48820, 14p.QuebecExploration - assessment
DS200612-0561
2006
Belanger, E.Heir Majumder, C.A., Travis, B.J., Belanger, E., Richard, G., Vincent, A.P., Yuen, D.A.Efficient sensitivity analysis for flow and transport in the Earth's crust and mantle.Geophysical Journal International, Vol. 166, 2, pp. 907-922.MantleGeophysics - seismics
DS1988-0049
1988
Belanger, J.R.Belanger, J.R.Prospecting in glaciated terrain: an approach based on geobotany biogeochemistry and remote sensingGeological Survey of Canada Bulletin, No. 387, 38p. $ 15.00 Database # 17527CanadaGeochemistry, Geobotany, Remote sensing- overview
DS200512-0870
2004
Belcourt, G.Power, M., Belcourt, G., Rockel, E.Geophysical methods for kimberlite exploration in northern Canada.Leading Edge, Vol. 23, 11, pp. 1124-1129.Canada, Northwest TerritoriesGeophysics - brief overview
DS201412-0047
2014
Belcourt, G.Belcourt, G., Hrkac, C., Vivian, G.Kennady North property: 2014 geophysical update.2014 Yellowknife Geoscience Forum, P. 14, abstractCanada, Northwest TerritoriesGeophysics
DS201512-1897
2015
Belcourt, G.Belcourt, G.A 2015 geophysical update for Kennady North project, NT.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 16.Canada, Northwest TerritoriesDeposit - Kennady North

Abstract: This presentation will provide an update of geophysical surveys performed in 2015. These surveys were undertaken to aid in the delineation of known kimberlites and discovery of potential kimberlite targets on Kennady Diamonds Inc.'s Kennady North Property. In 2015, Kennady Diamonds Inc. focused most of their geophysical budget on expansion of the known kimberlites. Previous OhmMapper surveys were expanded in the Doyle & MZ Areas in order to provide locations for exploration drilling. Ground based Gravity surveys were completed using an increased sample density in key areas. This increased density in the gravity data proved to be very helpful in the detailed drilling of the Kelvin and Faraday kimberlite bodies. Late in the summer season, a small scale marine seismic system was utilized on the Kelvin and Faraday lakes. This data will hopefully be used to discover potential areas of new or thicker kimberlite under the lake. As the Kelvin and Faraday kimberlites are not the typical pipe-like bodies, many different geophysical tools from our toolbox must be utilized.
DS1982-0087
1982
Belesha, S.N.Bartoshinskii, Z.V., Belesha, S.N., et al.Dissolution Cones of Zirconium Crystals from the Kimberlite pipe Mir.Doklady Academy of Sciences AKAD. NAUK SSSR., Vol. 267, No. 6, PP. 1444-1447.RussiaBlank
DS2002-0134
2002
Belevantsev, V.I.Belevantsev, V.I., Roslyakov, N.A., Kalinin, Y.A.Geochemical relation of gold to NH 4 in hydrothermal gold depositsGeochemistry International, Vol.40,4,pp. 411-19.GlobalGold - geochemistry, mineralogy
DS2000-0075
2000
Belgium Economic and Commercial InformationBelgium Economic and Commercial InformationBelgian diamonds and jewellery. A bright futureBelgium Econ. Comm. Info., 32p.BelgiumDiamond industry - jewellery
DS2000-0076
2000
Belgium Economic and Commercial InformationBelgium Economic and Commercial InformationAntwerp: a diamond's best friend... leading the diamond industry into the 21st. Century.Belgium Econ. Comm. Info., 35p.BelgiumDiamond industry - jewellery, Antwerp diamond Centre
DS1860-0539
1887
Belgrave, D.J.Belgrave, D.J.Luck at the Diamond FieldsLondon: Ward And Downey, 393P.Africa, South AfricaHistory
DS202006-0942
2020
Beliatsky, B.V.Nikitina, L.P., Goncharov, A.G., Bogomolov, E.S., Beliatsky, B.V., Krimsky, R.Sh., Prichodko, V.S., Babushkina, M.S., Karaman, A.A.HFSE and REE geochemistry and Nd-Sr-Os systematics of peridotites in the subcontinental lithospheric mantle of the Siberian craton and central Asian fold belt junction area: data on mantle xenoliths.Petrology, Vol. 28, 2, pp. 207-219.RussiaREE

Abstract: Mantle xenoliths were found in alkaline basalts of Tokinsky Stanovik (TSt) in the Dzhugdzhur-Stanovoy superterrane (DS) and Vitim plateau (VP) in the Barguzin-Vitim superterrane (BV) (Stanovoy suture area) at junction of the Central Asian Orogenic Belt (CAOB) and the Siberian craton (SC). Xenoliths from TSt basalts are represented by spinel lherzolites, harzburgites, wehrlites; while VP basalts frequently contain spinel-garnet and garnet peridotites lherzolites, and pyroxenites. Xenoliths in kimberlites of the Siberian craton are mainly represented by garnet-bearing lherzolites with abundant eclogite xenoliths (age of 2.7-3.1 Ga), which were not found in mantle of superterranes. The Re-Os determinations point to the Early Archean age of peridotites and eclogites from mantle beneath the Siberian craton. The major and trace (rare-earth and high-filed strength) elements and Nd-Sr-Os composition were analyzed in the peridotites (predominant rocks) of lithospheric mantle at junction of the Central Asian Orogenic Belt and Siberian Craton. The degree of rock depletion in CaO and Al2O3 and enrichment in MgO relative to the primitive mantle in the peridotites of the Dzhugdzhur-Stanovoy superterrane is close to that of the Siberian craton. The peridotites of the Barguzin-Vitim superterrane are characterized by much lower degree of depletion and have mainly a primitive composition. Mantle melting degree reaches up to 45-50% in the Siberian Craton and Dzhugdzhur-Stanovoy superterrane, and is less than 25% in the Barguzin-Vitim terrane. The mantle peridotites of the craton as compared to those of adjacent superterranes are enriched in Ba, Rb, Th, Nb, and Ta and depleted in Y and REE from Sm to Lu. However, all studied peridotites are characterized by mainly superchondritic values of Nb/Ta (>17.4), Zr/Hf (>36.1), Nb/Y (>0.158), and Zr/Y (>2.474). The Nb/Y ratio is predominantly >1.0 in SC peridotites and < 1.0 in the superterrane peridotites. The Nd and Sr isotopic compositions in the latter correspond to those of oceanic basalts. The 187Os/188Os ratio is low (0.108-0.115) in the peridotites of the Siberian Craton and > 0.115 but usually lower than 0.1296 (primitive upper mantle value) in the peridotites of the Dzhugdzhur-Stanovoy and Barguzin-Vitim superterranes. Thus, the geochemical and isotopic composition of peridotites indicates different compositions and types of mantle beneath the Siberian craton and adjacent superterranes of the Central Asian Orogenic Belt in the Early Archean, prior to the formation of 2.7-3.1 Ga eclogites in the cratonic mantle.
DS2002-1802
2002
Belichenko, B.G.Zorin, Y.A., Mordvinova, V.V., Turutanov, E.K., Belichenko, B.G., ArtemyevA low seismic velocity layers in the Earth's crust beneath Siberia and central Mongolia:Tectonophysics, Vol. 359, No. 3-4, pp. 307-27.Russia, Siberia, MongoliaGeophysics - seismics
DS1998-1650
1998
Belichenko, V.G.Zorin, Yu.A., Belichenko, V.G.Terranes of East Mongolia and Central Transbaikalia and evolution of the Okhotsk Mongolian fold belt.Russian Geology and Geophysics, Vol. 39, No. 1, pp. 11-25.GlobalTectonics
DS1975-0688
1978
Belimenko, L.D.Belimenko, L.D., Shemanina, YE.I., Samoylovich, M.I.A Comparative Electron Microscopy Study of Natural Diamonds from the Urals and Yakutsk.Nov. Dannyye Miner. Sssr., No. 27, PP. 19-27.RussiaMicroprobe
DS1980-0058
1980
Belimenko, L.D.Belimenko, L.D., Gorokov, S.S., Samoylovich, M.I.Characteristics of Real Structure of Small DiamondsTsnigri, No. 153, PP. 31-35.RussiaBlank
DS1980-0059
1980
Belimenko, L.D.Belimenko, L.D., Polkanov, YU.A., Samoylovich, M.I.Electron Microscopic Research on Diamonds from Titaniferous placers on the Russian PlatformTsnigri, No. 153, PP. 36-43.RussiaBlank
DS1981-0078
1981
Belimenko, L.D.Belimenko, L.D., et al.The Effect of Diamond Single Crystal Annealing Under Conditions of Their Thermodynamic Stability on the Formation and Transformation of Structural Imperfections.Doklady Academy of Sciences AKAD. NAUK SSSR., Vol. 259, No. 6, PP. 1360-1363.RussiaMicroprobe
DS1984-0423
1984
Belimenko, L.D.Korolev, D.F., Belimenko, L.D., et al.Function of Catalyst in Conversion of Graphite Into Diamond at High Pressure.Inorganic Material, Vol. 20, No. 1, JANUARY PP. 49-52.GlobalDiamond Morphology, Crystallography
DS1993-0101
1993
Beliolipetsky, A.P.Beliolipetsky, A.P., Mitrofanov, F.P.Rare earth mineralization in alkaline complexes on the Kola PeninsulaRare earth Minerals: chemistry, origin and ore deposits, International Geological Correlation Programme (IGCP) Project, pp. 11-12. abstractRussia, Kola PeninsulaRare earths, Alkaline rocks
DS2001-0400
2001
Belitski, I.A.Goryainov, S.V., Belitski, I.A., Likhacheva, FursenkoRaman spectroscopy of high pressure phase transition in analcime and leuciteRussian Geology and Geophysics, Vol. 41, No. 5, pp. 673-81.GlobalSpectroscopy
DS201809-2043
2018
Belivanova, V.Ivarsson, M., Skogby, H., Bengtson, S., Siljestrom, S., Ounchanum, P., Boonsoong, A., Kruachanta, M., Marone, F., Belivanova, V., Holstrom, S.Intricate tunnels in garnets from soils and river sediments in Thailand - possible endolithic microborings.PluS One, Vol. 13, 8, doi:10.1371/journal.pone.0200351Asia, Thailandgarnets

Abstract: Garnets from disparate geographical environments and origins such as oxidized soils and river sediments in Thailand host intricate systems of microsized tunnels that significantly decrease the quality and value of the garnets as gems. The origin of such tunneling has previously been attributed to abiotic processes. Here we present physical and chemical remains of endolithic microorganisms within the tunnels and discuss a probable biological origin of the tunnels. Extensive investigations with synchrotron-radiation X-ray tomographic microscopy (SRXTM) reveal morphological indications of biogenicity that further support a euendolithic interpretation. We suggest that the production of the tunnels was initiated by a combination of abiotic and biological processes, and that at later stages biological processes came to dominate. In environments such as river sediments and oxidized soils garnets are among the few remaining sources of bio-available Fe2+, thus it is likely that microbially mediated boring of the garnets has trophic reasons. Whatever the reason for garnet boring, the tunnel system represents a new endolithic habitat in a hard silicate mineral otherwise known to be resistant to abrasion and chemical attack.
DS2000-0971
2000
BelkaValverde-Vaquero, P., Dorr, Belka, Franke, WiszniewskaUranium-lead (U-Pb) single grain dating of detrital zircon in the Cambrian of central Poland: implications for GondwanaEarth and Planetary Science Letters, Vol. 184, No.1, Dec.30, pp. 225-40.GlobalTectonics - Baltica, Trans European Suture Zone - not specific to diamonds
DS1987-0043
1987
Belkanova, N.P.Belkanova, N.P., Eroshechev-Shak, V.A., Lebedeva, E.V., KaravaikoDissolution of kimberlite minerals by heterotrophusmicroorganisms.(Russian)Mikrobiologiya, (Russian), Vol. 56, No. 4, pp. 613-620RussiaBacterial breakdown
DS1989-0101
1989
Belkin, H.E.Belkin, H.E., DeVivo, B.Glass, phlogopite and apatite in spinel peridotite xenoliths from Sardinia (Italy): evidence for mantleMetasomatismNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 20. AbstractGlobalMantle, Metasomatism
DS201212-0737
2012
Belkin, H.E.Tucker, R.D., Belkin, H.E., Schulz, K.J., Peters, S.G., Horton, F.A major light rare earth element (LREE) resource in the Khanneshin carbonatite complex, southern Afghanistan.Economic Geology, Vol. 107, 2, pp. 197-208.Europe, AfghanistanCarbonatite
DS2001-0526
2001
BellJames, D., Boyd, Bell, Schutt, CarlsonXenolith constraints on seismic velocities in the upper mantle beneath southern Africa.Slave-Kaapvaal Workshop, Sept. Ottawa, 2p. abstractSouth Africa, BotswanaGeophysics - seismics, Tomography - Kaapvaal Craton
DS201707-1307
2017
Bell, A.S.Bell, A.S., Shearer, C., Burger, P., Ren, M., Newville, M., Lanzirotti, A.Quantifying and correcting the effects of anisotropy in Xanes measurements of chromium valence in olivine: implications for a new olivine oxybarometer.American Mineralogist, Vol. 102, pp. 1165-1172.Technologyolivine

Abstract: Chromium valence ratios in igneous olivine may hold a wealth of redox information about the melts from which they crystallized. It has been experimentally shown that the Cr2+/?Cr of olivine varies systematically with fO2, therefore measurements of Cr valence in olivine could be employed as a quantitative oxybarometer. In situ synchrotron µ-XANES analyses of Cr valence ratios of individual olivine phenocrysts in thin section have the potential to unlock this stored magmatic redox information on a fine spatial scale. However, there are still obstacles to obtaining accurate XANES measurements of cation valence in crystalline materials, as the results from these measurements can be compromised by anisotropic absorption effects related to the crystallographic orientation of the sample. Improving the accuracy of XANES measurements of Cr valence ratios in olivine by calibrating an anisotropy correction is a vital step in developing Cr valence measurements in olivine as a rigorous oxybarometer. To accomplish this goal, we have used an integrated approach that combined experiments, electron backscatter diffraction analysis, and XANES measurements in olivine to systematically examine how orientation affects the resultant Cr K-edge XANES spectra and the Cr valence ratios that are calculated from them. The data set generated in this work was used to construct a model that mitigates the effects of anisotropy of the calculated Cr2+/?Cr values. The application of this correction procedure as a part of spectral processing improves the overall accuracy of the resultant Cr2+/?Cr values by nearly a factor of five. The increased accuracy of the XANES measured Cr valence ratios afforded by the anisotropy correction reduces the error on calculated fO2 values from approximately ±1.2 to ±0.25
DS1999-0165
1999
Bell, B.R.Dempster, T.J., Preston, R.J., Bell, B.R.The origin of Proterozoic massif type anorthosites: evidence from interactions between crustal xenoliths...Journal of Geological Society of London, Vol. 156, No. 1, Jan. pp. 41-46.Mantle, CrustBasaltic magma, Xenoliths
DS2002-0786
2002
Bell, B.R.Jolley, D.W., Bell, B.R.The North Atlantic Igneous Province: stratigraphy, tectonic, volcanic and magmatic processes.Geological Society of London (U.K.), 344p.$ 142.00 http://bookshop.geolsoc.org.ukNorway, GreenlandBook - igneous and sedimentary processes
DS2002-0787
2002
Bell, B.R.Jolley, D.W., Bell, B.R.The North Atlantic Igneous Province: stratigraphy, tectonic, volcanic and magmatic processes.Geological Society of London Special Paper, No. 197, 344p.$ 200. www.geosoc.orgNorway, Greenland, DenmarkBook
DS2003-0776
2003
Bell, B.R.Le Roex, A.P., Bell, B.R., Davis, P.Petrogenesis of Kimberley group 1 hypabyssal kimberlites: evidence from bulk rock8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractSouth AfricaKimberlite petrogenesis, Deposit - Kimberley pipes
DS200412-0480
2004
Bell, B.R.Doyle, P.M., Bell, B.R., Le Roex, A.P.Fine grained pyroxenites from the Gansfontein kimberlite, South Africa: evidence for megacryst magma - mantle interaction.South African Journal of Geology, Vol. 107, 1/2, pp. 285-300.Africa, South AfricaDeposit - Gansfontein, petrology
DS200412-1092
2003
Bell, B.R.Le Roex, A.P., Bell, B.R., Davis, P.Petrogenesis of Kimberley group 1 hypabyssal kimberlites: evidence from bulk rock geochemistry.8 IKC Program, Session 7, AbstractAfrica, South AfricaKimberlite petrogenesis Deposit - Kimberley pipes
DS1995-1778
1995
Bell, D.Smith, C.B., Shulze, D.J., Bell, D., Vijoen, K.S.Bearing of the subcalcic chromium poor megacryst suite on kimberlite petrogenesis and lithospheric structure.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 546-548.South AfricaMegacrysts, Deposit -Kaalvallei, Frank Smith, Lace
DS2002-1707
2002
Bell, D.Whitehead, K., Le Roex, A., Class, C., Bell, D.Composition and Cretaceous thermal structure of the upper mantle beneath the Damara Mobile Belt: evidenceJournal of Geological Society of London, Vol.159,pp.307-21., Vol.159,pp.307-21.NamibiaNepheline hosted peridotite xenoliths, Gibeon compariso, Deposit - Swakopmund area
DS2002-1708
2002
Bell, D.Whitehead, K., Le Roex, A., Class, C., Bell, D.Composition and Cretaceous thermal structure of the upper mantle beneath the Damara Mobile Belt: evidenceJournal of Geological Society of London, Vol.159,pp.307-21., Vol.159,pp.307-21.NamibiaNepheline hosted peridotite xenoliths, Gibeon compariso, Deposit - Swakopmund area
DS201012-0321
2010
Bell, D.Janney, P., Bell, D.Pb isotope evidence of a cognate origin for Cr poor megacrysts in southern African kimberlites.Goldschmidt 2010 abstracts, posterAfrica, South AfricaGeochronology
DS1981-0079
1981
Bell, D.R.Bell, D.R.Ultramafic Xenoliths from the Koffiefontein Kimberlite PipeBsc. Hons. Thesis University Cape Town., South AfricaBlank
DS1986-0205
1986
Bell, D.R.Edgar, A.D., Arima, M., Baldwin, D.K., Bell, D.R., Shee, S.R., Skinner, E.M.high pressure melting experiments on an aphanitic kimberlite from the Wesselton mine, Kimberley South AfricaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 170-172South AfricaBlank
DS1986-0730
1986
Bell, D.R.Shee, S.R., Bristow, J.W., Shee, P.B.S., Bell, D.R.The petrology of kimberlites, related rocks and associated mantle xenoliths from the Kuruman province, South Africa #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 90-92South AfricaPetrology
DS1988-0188
1988
Bell, D.R.Edgar, A.D., Arima, M., Baldwin, D.K., Bell, D.R., Shee, S.R.High-pressure-high temperature melting experiments on a SiO2poor aphanitic kimberlite from the Wesselton mine, Kimberley,South AfricaAmerican Mineralogist, Vol. 73, No. 5-6 May June pp. 524-533South AfricaBlank
DS1989-1379
1989
Bell, D.R.Shee, S.R., Bristow, J.W., Bell, D.R., Smith, C.B., Allsopp, H.L.The petrology of kimberlites, related rocks and associated mantle xenoliths from the Kuruman province, South Africa #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 1, pp. 60-82South AfricaMantle, Petrology
DS1990-0184
1990
Bell, D.R.Bell, D.R., Rossman, G.R.Hydroxyl in anhydrous minerals from eclogite xenolithsEos, Vol. 71, No. 17, April 24, p. 523 Abstract onlySouth Africa, Colorado PlateauEclogite, Xenoliths
DS1991-1619
1991
Bell, D.R.Smyth, J.R., Bell, D.R., Rossman, G.R.in corporation of hydroxyl in upper-mantle clinopyroxenesNature, Vol. 351, June 27, pp. 732-735GlobalMantle, Water -melts
DS1992-0109
1992
Bell, D.R.Bell, D.R.Water in mantle mineralsNature, Vol. 357, No. 6380, June 25, pp. 646-647GlobalMantle minerals, Water in the evolution of the earth
DS1992-0110
1992
Bell, D.R.Bell, D.R.The distribution of hydroxyl in garnets from the subcontinental mantle of southern AfricaContributions to Mineralogy and Petrology, Vol. 111, No. 2, July pp. 143-160South Africa, southern AfricaGarnet, mineralogy, Mantle
DS1992-0111
1992
Bell, D.R.Bell, D.R., Rossman, G.R.Water in earth's mantle - the role of nominally anhydrous mineralsScience, Vol. 285, No. 5050, March 13, pp. 1391-1397MantleAnhydrous minerals, Mineralogy
DS1993-0102
1993
Bell, D.R.Bell, D.R., Rossman, G.R.The trace element partioning of Hydrogen in a High-pressure igneous system: megacrysts from the Monastery kimberliteEos, Transactions, American Geophysical Union, Vol. 74, No. 16, April 20, supplement abstract p. 340South AfricaCrystal chemistry
DS1995-0133
1995
Bell, D.R.Bell, D.R., Gurney, J.J., Le Roex, A.P., Moore, R.O, et al.Compositional evolution of the Monastery megacrysts and parent magmaProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 50-51.South AfricaPetrology, Deposit -Monastery
DS1995-0134
1995
Bell, D.R.Bell, D.R., Schulze, D.J., Read, G.H., et al.Geochemistry of chromium poor megacrysts from the Lace (Group II) South Africa.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 52-54.South AfricaGeochemistry, Deposit -Crown (Lace)
DS1998-0102
1998
Bell, D.R.Bell, D.R., Mofokeng, S.W.chromium poor megacrysts from the Frank Smith mine and source regions of transitional kimberlites.7th International Kimberlite Conference Abstract, pp. 64-66.South AfricaKimberlites, Orangeites, Deposit - Frank Smith
DS1998-0550
1998
Bell, D.R.Gurney, J.J., Moore, R.O., Bell, D.R.Mineral associations and compositional evolution of Monastery kimberlitemegacrysts.7th International Kimberlite Conference Abstract, pp. 290-2.South AfricaPetrogenetic - Metasomatism, Deposit - Monastery
DS1998-1301
1998
Bell, D.R.Schulze, D.J., Valley, J.W., Bell, D.R., Spicuzza, M.Significance of oxygen isotope variations in the chromium-poor megacryst suite7th. Kimberlite Conference abstract, pp. 769-71.South Africa, North AmericaKimberlite - Group I, II, Subduction
DS2000-0077
2000
Bell, D.R.Bell, D.R., Ibinger, P.D.The isotopic composition of hydrogen in nominally anhydrous mantle mineralsGeochimica et Cosmochimica Acta, Vol. 64, No. 12, June 1, pp. 2109-18.MantleGeochronology, Hydrogen
DS2001-1039
2001
Bell, D.R.Schulze, D.K., Valley, J.R., Bell, D.R., Spicuzza, M.Oxygen isotope variations in Cromium poor megacrysts from kimberliteGeochimica et Cosmochimica Acta., Vol. 65, No. 23, pp. 4375-84.Ontario, South AfricaGeochronology, Chromium
DS2002-0613
2002
Bell, D.R.Gregoire, M., Bell, D.R., Le Roex, A.P.Trace element geochemistry of phlogopite rich mafic mantle xenoliths: their classification and relationshipContributions to Mineralogy and Petrology, Vol. 142, No. 5, Feb. pp. 603-25.MantlePeridotites, kimberlites - phlogopite bearing, Kimberlites
DS2003-0023
2003
Bell, D.R.Appleyard, C.M., Le Roex, A.P., Bell, D.R.The geochemistry of a suite of eclogite xenoliths from the Rietfontein kimberlite, South8ikc, Www.venuewest.com/8ikc/program.htm, Session 2, POSTER abstractSouth AfricaEclogites and Diamonds, Deposit - Rietfontein
DS2003-0094
2003
Bell, D.R.Bell, D.R., Gregoire, M., Grove, T.L., Chatterjee, N.D., Bowring, S.A.Silica and carbon deposition in Kimberley peridotites8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, AbstractSouth AfricaMantle petrology, Deposit - Bultfontein
DS2003-0095
2003
Bell, D.R.Bell, D.R., Schmitz, M.D., Janney, P.E.Mesozoic thermal evolution of the southern African mantle lithosphereLithos, Vol. 71, 2-4, pp. 273-87.South AfricaGeothermometry
DS2003-0292
2003
Bell, D.R.Coussaert, N., Gregoire, M., Mercier, J.C.C., Bell, D.R., Demaiffe, D., Le RoexThe origin of clinopyroxene in cratonic mantle8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractSouth AfricaMantle geochemistry, Deposit - Bultfontein, Jagersfontein, Monastery, Premie
DS2003-0500
2003
Bell, D.R.Gregoire, M., Bell, D.R., LeRoex, A.P.Garnet lherzolites from the Kaapvaal Craton ( South Africa): trace element evidence forJournal of Petrology, Vol. 44, 4, pp. 629-58.South AfricaMineralogy, Metasomatism
DS2003-0646
2003
Bell, D.R.Janney, P.E., Le Roex, A.P., Carlson, R.W., Bell, D.R.Os and Hf isotope constraints on the sources of olivine melilitites from western South8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractSouth AfricaGeochronology
DS2003-0777
2003
Bell, D.R.Le Roex, A.P., Bell, D.R., Davis, P.Petrogenesis of Group I kimberlites from Kimberley, South Africa: evidence from bulkJournal of Petrology, Vol. 44, 12, pp. 2261-86.South AfricaPetrology - Kimberley deposit
DS200412-0127
2003
Bell, D.R.Bell, D.R., Gregoire, M., Grove, T.L., Chatterjee, N.D., Bowring, S.A.Silica and carbon deposition in Kimberley peridotites.8 IKC Program, Session 6, AbstractAfrica, South AfricaMantle petrology Deposit - Bultfontein
DS200412-0128
2004
Bell, D.R.Bell, D.R., Moore, R.O.Deep chemical structure of the southern African mantle from kimberlite megacrysts.South African Journal of Geology, Vol. 107, 1/2, pp. 59-80.Africa, South AfricaGeochemistry, tectonics
DS200412-0129
2004
Bell, D.R.Bell, D.R., Rossman, G.R., Moore, R.O.Abundance and partitioning of OH in a high pressure magmatic system: megacrysts from the Monastery kimberlite, South Africa.Journal of Petrology, Vol. 45, 8, pp. 1539-1564.Africa, South AfricaMineral chemistry - Monastery
DS200412-0130
2003
Bell, D.R.Bell, D.R., Schmitz, M.D., Janney, P.E.Mesozoic thermal evolution of the southern African mantle lithosphere.Lithos, Vol. 71, 2-4, pp. 273-87.Africa, South AfricaGeothermometry
DS200412-0459
2004
Bell, D.R.Dixon, J.E., Dixon, T.H., Bell, D.R., Malservisi, R.Lateral variation in upper mantle viscosity: role of water.Earth and Planetary Science Letters, Vol. 222, 2, pp. 451-467.United States, ColoradoWater - chemistry, xenoliths
DS200412-0717
2003
Bell, D.R.Gregoire, M., Bell, D.R., LeRoex, A.P.Garnet lherzolites from the Kaapvaal Craton ( South Africa): trace element evidence for a metasomatic history.Journal of Petrology, Vol. 44,4,pp. 629-58.Africa, South AfricaMineralogy Metasomatism
DS200412-0903
2003
Bell, D.R.Janney, P.E., Le Roex, A.P., Carlson, R.W., Bell, D.R.Os and Hf isotope constraints on the sources of olivine melilitites from western South Africa.8 IKC Program, Session 7, POSTER abstractAfrica, South AfricaKimberlite petrogenesis Geochronology
DS200412-1093
2003
Bell, D.R.Le Roex, A.P., Bell, D.R., Davis, P.Petrogenesis of Group I kimberlites from Kimberley, South Africa: evidence from bulk rock geochemistry.Journal of Petrology, Vol. 44, 12, pp. 2261-86.Africa, South AfricaPetrology - Kimberley deposit
DS200412-1448
2004
Bell, D.R.Nowell, G.M., Pearson, D.G., Bell, D.R., Carlson, R.W., Smith, C.B., Kempton, P.D., Noble, S.R.Hf isotope systematics of kimberlites and their megacrysts: new constraints on their source regions.Journal of Petrology, Vol. 45, 8, pp. 1583-1612.Africa, South AfricaGeochronology
DS200512-0367
2005
Bell, D.R.Gregoire, M., Tinguely, C., Bell, D.R., Le Roex, A.P.Spinel lherzolite xenoliths from the Premier kimberlite ( Kaapvaal craton) South Africa: nature and evolution of the shallow upper mantle beneath Bushveld Complex.Lithos, Vol. 84, 3-4, Oct. pp. 185-205.Africa, South AfricaPetrology - Premier, melting, metasomatism
DS200612-0115
2005
Bell, D.R.Bell, D.R., Gregoire, M., Grove, T.L., Chaterjee, N., Carlson, R.W., Buseck, P.R.Silica and volatile element metasomatism of Archean mantle: a xenolith scale example from the Kaapvaal Craton.Contributions to Mineralogy and Petrology, Vol. 150, 3, pp. 251-267.Africa, South AfricaMetasomatism
DS200712-0021
2007
Bell, D.R.Appleyard, C.M., Bell, D.R., Roex, A.P.Petrology and geochemistry of eclogite xenoliths from the Rietfontein kimberlite, northern Cape, South Africa.Contributions to Mineralogy and Petrology, Vol. 154, 3m pp. 309-333.Africa, South AfricaDeposit - Rietfontein
DS200712-0022
2007
Bell, D.R.Appleyard, C.M., Bell, D.R., Roex, A.P.Petrology and geochemistry of eclogite xenoliths from the Rietfontein kimberlite, northern Cape, South Africa.Contributions to Mineralogy and Petrology, Vol. 154, 3, pp. 309-333.Africa, South AfricaRietfontein
DS200712-0724
2007
Bell, D.R.Michaut, C., Jaupart, C., Bell, D.R.Transient geotherms in Archean continental lithosphere: new constraints on thickness and heat production of the subcontinental lithospheric mantle.Journal of Geophysical Research, Vol. 112, B4, B04408.Africa, South AfricaKaapvaal Craton
DS200912-0043
2009
Bell, D.R.Bell, D.R.Some pecularities of kimberlite petrogenesis.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyTechnologyDifferences between kimberlites and other magmas
DS200912-0044
2009
Bell, D.R.Bell, D.R.Diamond bearing mantle of the Kaapvaal craton: implications for exploration models and craton root petrogenesis.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyAfrica, South AfricaKimberley diamond inclusions
DS200912-0045
2009
Bell, D.R.Bell, D.R., Hervig, R.L., Buseck, P.R., Aulbach, S.Lithium isotope analysis of olivine by SIMS: calibration of a matrix effect and application to magmatic phenocrysts.Chemical geology, Vol. 258, 1-2, Jan. pp. 5-16.Africa, South Africa, Tanzania, United StatesPhenocrysts
DS200912-0810
2009
Bell, D.R.Weiss, Y., Kessel, R., Griffin, W.L., Kiflawi, I., Klein-BenDavid, O., Bell, D.R., Harris, J.W., Navon, O.A new model for the evolution of diamond forming fluids: evidence from Micro inclusion bearing diamonds from Kankan, Guinea.Lithos, In press - available 43p.Africa, GuineaDeposit - Kankan
DS201012-0322
2010
Bell, D.R.Janney, P.E., Shirey, S.B., Carlson, R.W., Pearson, D.G., Bell, D.R., Le Roex, A., Ishikawa, Nixon, BoydAge, composition and thermal characteristics of South African off craton mantle lithosphere: evidence for a multi stage history.Journal of Petrology, Vol. 51, 9, pp. 1849-1890,Africa, South AfricaGeochronology, geothermometry
DS201012-0577
2010
Bell, D.R.Peslier, A.H., Woodland, A.B., Bell, D.R., Lazarov, M.Olivine water contents in the continental lithosphere and the longevity of cratons.Nature, Vol. 467, Sept. 2, pp. 78-81.MantleGeodynamics - cratons
DS201112-0476
2011
Bell, D.R.Janney, P.E., Bell, D.R.Pb Sr Nd Hf isotope variations of megacrysts from Mesozoic Southern African kimberlites reflect mixing of HIMU melts with deep lithosphere.Goldschmidt Conference 2011, abstract p.1102.Africa, South AfricaPofadder, Monastery
DS201112-1109
2011
Bell, D.R.Weiss, Y., Griffin, W.L., Bell, D.R., Navon, O.High Mg carbonatitic HDFs, kimberlites and SCLM.Goldschmidt Conference 2011, abstract p.2143.RussiaFibrous diamonds
DS201212-0550
2012
Bell, D.R.Peslier, A.H., Woodland, A.B., Bell, D.R., Lazarov, M., Lapen, T.J.Metasomatic control of water contents in the Kaapvaal cratonic mantle.Geochimica et Cosmochimica Acta, Vol. 97, pp. 213-246.Africa, South Africa, LesothoDeposit - Finsch, Kimberley, Jagersfontein, Letseng, Liqhobong
DS201212-0767
2012
Bell, D.R.Weiss, Y., Griffin, W.L., Bell, D.R., Navon, O.High Mg carbonatitic HDFS, kimberlites and the SCLM.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleCarbonatite
DS201312-0068
2013
Bell, D.R.Bell, D.R.Petrogenesis of the Navajo volcanic field: lessons from South African kimberlites.Geological Society of America Abstracts, Vol. 45, 5, p. 2.United States, Colorado PlateauMegacrysts
DS201412-0883
2013
Bell, D.R.Stanley, J.R., Flowers, R.M., Bell, D.R.Kimberlite ( U-Th) He dating links surface erosion with lithospheric heating, thinning, and metasomatism in the southern African Plateau.Geology, Vol. 4, pp. 1243-1246.AfricaGeochronology
DS201707-1308
2017
Bell, E.Bell, E.Ancient magma sources revealed. Nature Geoscience, Vol. 10, 6, pp. 397-398.Mantlemelting

Abstract: The composition of Earth's oldest crust is uncertain. Comparison of the most ancient mineral grains with more recent analogues suggests that formation of the earliest crust was heavily influenced by re-melting of igneous basement rocks.
DS201608-1390
2016
Bell, E.A.Bell, E.A., Boehnke, P., Harrison, T.M.Recovering the primary geochemistry of Jack Hills zircons through quantitative estimates of chemical alteration.Geochimica et Cosmochimica Acta, Vol. 191, pp. 187-202.AustraliaJack Hills REE

Abstract: Despite the robust nature of zircon in most crustal and surface environments, chemical alteration, especially associated with radiation damaged regions, can affect its geochemistry. This consideration is especially important when drawing inferences from the detrital record where the original rock context is missing. Typically, alteration is qualitatively diagnosed through inspection of zircon REE patterns and the style of zoning shown by cathodoluminescence imaging, since fluid-mediated alteration often causes a flat, high LREE pattern. Due to the much lower abundance of LREE in zircon relative both to other crustal materials and to the other REE, disturbance to the LREE pattern is the most likely first sign of disruption to zircon trace element contents. Using a database of 378 (148 new) trace element and 801 (201 new) oxygen isotope measurements on zircons from Jack Hills, Western Australia, we propose a quantitative framework for assessing chemical contamination and exchange with fluids in this population. The Light Rare Earth Element Index is scaled on the relative abundance of light to middle REE, or LREE-I = (Dy/Nd) + (Dy/Sm). LREE-I values vary systematically with other known contaminants (e.g., Fe, P) more faithfully than other suggested proxies for zircon alteration (Sm/La, various absolute concentrations of LREEs) and can be used to distinguish primary compositions when textural evidence for alteration is ambiguous. We find that zircon oxygen isotopes do not vary systematically with placement on or off cracks or with degree of LREE-related chemical alteration, suggesting an essentially primary signature. By omitting zircons affected by LREE-related alteration or contamination by mineral inclusions, we present the best estimate for the primary igneous geochemistry of the Jack Hills zircons. This approach increases the available dataset by allowing for discrimination of on-crack analyses (and analyses with ambiguous or no information on spot placement or zircon internal structures) that do not show evidence for chemical alteration. It distinguishes between altered and unaltered samples in ambiguous cases (e.g., relatively high Ti), identifying small groups with potentially differing provenance from the main Jack Hills population. Finally, filtering of the population using the LREE-I helps to more certainly define primary correlations among trace element variables, potentially relatable to magmatic compositional evolution.
DS201611-2099
2016
Bell, E.A.Bell, E.A., Boehnke, P., Harrison, T.M.Recovering the primary geochemistry of Jack Hills zircons through quantitative estimates of chemical alteration.Geochimica et Cosmochimica Acta, Vol. 191, pp. 187-202.AustraliaGeochemistry

Abstract: Despite the robust nature of zircon in most crustal and surface environments, chemical alteration, especially associated with radiation damaged regions, can affect its geochemistry. This consideration is especially important when drawing inferences from the detrital record where the original rock context is missing. Typically, alteration is qualitatively diagnosed through inspection of zircon REE patterns and the style of zoning shown by cathodoluminescence imaging, since fluid-mediated alteration often causes a flat, high LREE pattern. Due to the much lower abundance of LREE in zircon relative both to other crustal materials and to the other REE, disturbance to the LREE pattern is the most likely first sign of disruption to zircon trace element contents. Using a database of 378 (148 new) trace element and 801 (201 new) oxygen isotope measurements on zircons from Jack Hills, Western Australia, we propose a quantitative framework for assessing chemical contamination and exchange with fluids in this population. The Light Rare Earth Element Index is scaled on the relative abundance of light to middle REE, or LREE-I = (Dy/Nd) + (Dy/Sm). LREE-I values vary systematically with other known contaminants (e.g., Fe, P) more faithfully than other suggested proxies for zircon alteration (Sm/La, various absolute concentrations of LREEs) and can be used to distinguish primary compositions when textural evidence for alteration is ambiguous. We find that zircon oxygen isotopes do not vary systematically with placement on or off cracks or with degree of LREE-related chemical alteration, suggesting an essentially primary signature. By omitting zircons affected by LREE-related alteration or contamination by mineral inclusions, we present the best estimate for the primary igneous geochemistry of the Jack Hills zircons. This approach increases the available dataset by allowing for discrimination of on-crack analyses (and analyses with ambiguous or no information on spot placement or zircon internal structures) that do not show evidence for chemical alteration. It distinguishes between altered and unaltered samples in ambiguous cases (e.g., relatively high Ti), identifying small groups with potentially differing provenance from the main Jack Hills population. Finally, filtering of the population using the LREE-I helps to more certainly define primary correlations among trace element variables, potentially relatable to magmatic compositional evolution.
DS201902-0284
2019
Bell, E.A.Keller, C.B., Husson, J.M., Mitchell, R.N., Bottke, W.F., Gernon, T.M., Boehnke, P., Bell, E.A., Swanson-Hysell, N.L., Peters, S.E.Neoproterozoic glacial origin of the Great Unconformity.PNAS, pnas.org/cqi/doi/10.1073/ pnas.1804350116 10p.Mantlegeomorphology

Abstract: The Great Unconformity, a profound gap in Earth’s stratigraphic record often evident below the base of the Cambrian system, has remained among the most enigmatic field observations in Earth science for over a century. While long associated directly or indirectly with the occurrence of the earliest complex animal fossils, a conclusive explanation for the formation and global extent of the Great Unconformity has remained elusive. Here we show that the Great Unconformity is associated with a set of large global oxygen and hafnium isotope excursions in magmatic zircon that suggest a late Neoproterozoic crustal erosion and sediment subduction event of unprecedented scale. These excursions, the Great Unconformity, preservational irregularities in the terrestrial bolide impact record, and the first-order pattern of Phanerozoic sedimentation can together be explained by spatially heterogeneous Neoproterozoic glacial erosion totaling a global average of 3-5 vertical kilometers, along with the subsequent thermal and isostatic consequences of this erosion for global continental freeboard.
DS202001-0044
2019
Bell, E.A.Tang, F., Taylor, R.J.M., Einsle, J.F., Borlina, C.S., Fu, R.R., Weiss, B.P., Williams, H.M., Williams, W., Nagy, L., Midgley, P.A., Lima, E.A., Bell, E.A., Harrison, T.M., Alexander, E.W., Harrison, R.J.Secondary magnetite in ancient zircon precludes analysis of a Hadean geodynamo. Jack HillsProceedings National Academy of Science, Vol. 116, pp. 407-412.Australiapaleomagnetism

Abstract: Zircon crystals from the Jack Hills, Western Australia, are one of the few surviving mineralogical records of Earth’s first 500 million years and have been proposed to contain a paleomagnetic record of the Hadean geodynamo. A prerequisite for the preservation of Hadean magnetization is the presence of primary magnetic inclusions within pristine igneous zircon. To date no images of the magnetic recorders within ancient zircon have been presented. Here we use high-resolution transmission electron microscopy to demonstrate that all observed inclusions are secondary features formed via two distinct mechanisms. Magnetite is produced via a pipe-diffusion mechanism whereby iron diffuses into radiation-damaged zircon along the cores of dislocations and is precipitated inside nanopores and also during low-temperature recrystallization of radiation-damaged zircon in the presence of an aqueous fluid. Although these magnetites can be recognized as secondary using transmission electron microscopy, they otherwise occur in regions that are indistinguishable from pristine igneous zircon and carry remanent magnetization that postdates the crystallization age by at least several hundred million years. Without microscopic evidence ruling out secondary magnetite, the paleomagnetic case for a Hadean-Eoarchean geodynamo cannot yet been made.
DS202012-2232
2020
Bell, J.McManus, C.E., McMillan, N.J., Dowe, J., Bell, J.Diamonds certify themselves: multivariate statistical provenance analysis.MDPI Minerals, Vol. 10, 916, doi:10.2290/ min0100916, 12p. PdfGlobalspectroscopy

Abstract: The country or mine of origin is an important economic and societal issue inherent in the diamond industry. Consumers increasingly want to know the provenance of their diamonds to ensure their purchase does not support inhumane working conditions. Governments around the world reduce the flow of conflict diamonds via paper certificates through the Kimberley Process, a United Nations mandate. However, certificates can be subject to fraud and do not provide a failsafe solution to stopping the flow of illicit diamonds. A solution tied to the diamonds themselves that can withstand the cutting and manufacturing process is required. Here, we show that multivariate analysis of LIBS (laser-induced breakdown spectroscopy) diamond spectra predicts the mine of origin at greater than 95% accuracy, distinguishes between natural and synthetic stones, and distinguishes between synthetic stones manufactured in different laboratories by different methods. Two types of spectral features, elemental emission peaks and emission clusters from C-N and C-C molecules, are significant in the analysis, indicating that the provenance signal is contained in the carbon structure itself rather than in inclusions.
DS1990-0185
1990
Bell, J.A.E.Bell, J.A.E.Value added productsThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 83, No. 933, January pp. 67-73GlobalCopper and nickel composites
DS1990-0186
1990
Bell, J.S.Bell, J.S., McCallum, R.E.In situ stress in the Peace River Arch area, western CanadaGeology of the Peace River Arch, ed. Sc.C. O'Connell, J.S. Bell, Bulletin. Can., Vol. 38A, Special Volume, December pp. 270-281AlbertaPeace River area, Tectonics, structure
DS1997-0086
1997
Bell, J.S.Bell, J.S., Wu, P.High horizontal stresses in Hudson Bay, CanadaCanadian Journal of Earth Sciences, Vol. 34, No. 7, July pp. 949-957.Ontario, ManitobaBasement, Paleozoic, Craton
DS1998-0416
1998
Bell, J.S.Feinstein, S., Eyal, Y., Bell, J.S.Implications of meso-structures for deformational history of Moose Mountain structure, Canadian RockiesJournal of Structural Geology, Vol. 21, No. 1, pp. 55-66.AlbertaStructure - faults
DS1970-0179
1970
Bell, K.Powell, J.L., Bell, K.Strontium Isotopic Studies of Alkalic Rocks; Localities From Australia, Spain and Western United States.Contributions to Mineralogy and Petrology, Vol. 27, PP. 1-10.Australia, Western Australia, Wyoming, United States, Rocky MountainsKimberlite, Leucite, Lamproite, Leucite Hills, Fitzroy Valley
DS1975-0359
1976
Bell, K.Mitchell, R.H., Bell, K.Rare Earth Geochemistry of Potassic Lavas from the Birunga And Toro-ankole Regions of UgAnd a Africa.Contributions to Mineralogy and Petrology, Vol. 58, PP. 293-303.GlobalBlank
DS1981-0080
1981
Bell, K.Bell, K., Dodson, M.H.The Geochronology of the Tanzanian ShieldJournal of GEOLOGY, Vol. 89, PP. 109-128.Tanzania, East Africa, Kenya, UgandaCraton, Age Dating, Isotope
DS1985-0056
1985
Bell, K.Bell, K., Blenkinsop, J.Carbonatites- Clues to Mantle EvolutionGeological Society of America (GSA), Vol. 17, No. 3, FEBRUARY P. 151. (abstract.).Canada, OntarioSuperior Crust, Isotope
DS1985-0721
1985
Bell, K.Wen, J., Bell, K., Blenkinsop, J.Strontium and Neodymium Isotopic Relationships in the Oka Carbonatite comp Lex, Canada.Geological Society of America (GSA), Vol. 17, No. 7, P. 747. (abstract.).Canada, QuebecGeochronology
DS1986-0063
1986
Bell, K.Bell, K., Blenkinsop, J.Carbonatites and the sub continental upper mantleGeological Association of Canada (GAC) Annual Meeting, Vol. 11, p. 44. (abstract.)East AfricaGeochronology, Carbonatite
DS1986-0313
1986
Bell, K.Grunenfelder, M.H., Tilton, G.R., Bell, K., Blenkinsop, J.Lead and strontium isotope relationship in the Oka carbonatitecomplex, QuebecGeochimica et Cosmochimica Acta, Vol. 50, pp. 461-468Quebec, UgandaMelilite, Carbonatite
DS1987-0044
1987
Bell, K.Bell, K., Blenkinsop, J.Neodynium and strontium isotopic compositions of East African carbonatites:implications for mantle heterogeneityGeology, Vol. 15, No. 2, pp. 99-102East AfricaCarbonatite, Geochronology
DS1987-0045
1987
Bell, K.Bell, K., Blenkinsop, J., Kwon, Tlton, SageAge and radiogenic isotopic systematics of the Border carbonatite complexOntario, canada.Canadian Journal of Earth Sciences, Vol. 24, pp. 24-30.OntarioGeochronology, deposit - Borden
DS1987-0787
1987
Bell, K.Wen, J., Bell, K., Blenkinsop, J.neodymium and Strontium isotope systematics of the Oka complex, Quebec and their bearing on the evolution of the sub-continental upper mantleContributions to Mineralogy and Petrology, Vol. 97, No. 4, pp. 433-437QuebecCarbonatite
DS1989-0102
1989
Bell, K.Bell, K., Blenkinsop, J.Neodynium and strontium isotope geochemistry of carbonatitesCarbonatites -Genesis and Evolution, Ed. K. Bell Unwin Hyman Publ, pp. 278-300East AfricaGeochemistry, Geochronology, Kimberlite
DS1989-1165
1989
Bell, K.Paces, J.B., Bell, K.Non-depleted sub-continental mantle beneath the Superior Province of the Canadian shield: neodymium-Sr isotopic and trace element evid. from Midcont. rift basaltsGeochimica et Cosmochimica Acta, Vol. 53, pp. 2023-2035MidcontinentTectonics, Rift
DS1991-1586
1991
Bell, K.Simonetti, A., Bell, K.Isotopic investigation of the Lake Chilwa carbonatite Complex, Malawi:implications for the origin of carbonatite magmasGeological Association of Canada (GAC)/Mineralogical Association of Canada/Society Economic, Vol. 16, Abstract program p. A114MalawiGeochronology, Carbonatite
DS1992-0112
1992
Bell, K.Bell, K.Isotopic dat a from carbonatite-nephelinite centres and the nature of the east African sub-continental upper mantleEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.329East Africa, UgandaCarbonatite, Nephelinite
DS1992-0442
1992
Bell, K.Ernst, R.E., Bell, K.Petrology of the Great Abitibi dyke, Superior Province, CanadaJournal of Petrology, Vol. 33, No. 2, April pp. 423-470QuebecPetrology, Abitibi Dyke
DS1992-1407
1992
Bell, K.Simonetti, A., Bell, K.neodymium, lead, and Strontium isotopic dat a Napak carbonatite -nephelinite centre, eastern Uganda: implications for crustal assimilation and fractional crystalizationEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.329UgandaCarbonatite, Nephelinite
DS1992-1602
1992
Bell, K.Veizer, J., Bell, K., Jansen, S.L.Temporal distribution of carbonatitesGeology, Vol. 20, No. 12, December pp. 1147-1149.MantleCarbonatite, Distribution
DS1993-0103
1993
Bell, K.Bell, K., Franklin, J.M.Application of lead isotopes to mineral exploration in glaciated terrainsGeology, Vol. 21, No. 12, December pp. 1143-1146.ManitobaVMS Sulphides, Deposit -Chisel Lake
DS1993-1468
1993
Bell, K.Simonetti, A., Bell, K.Isotopic disequilibrium in clinopyroxenes from nephelinitic lavas, Napakvolcano, eastern Uganda.Geology, Vol. 21, No. 3, March pp. 243-246.UgandaTectonics -rifting, Nephelinites
DS1994-0136
1994
Bell, K.Bell, K.Carbonatites and mantle evolution : a reviewMineralogical Magazine, Vol. 58A, pp. 69-70. AbstractCanadaCarbonatite
DS1994-0137
1994
Bell, K.Bell, K., Dawson, J.B.An assessment of the alleged role of evaporites and saline brines in the origins of natrocarbonatite.Carbonatite volcanism, Ed. Bell, K., Keller, J., pp. 137-147.TanzaniaPetrology - Carbonatite volcanism., Deposit -Oldoinyo Lengai
DS1994-0138
1994
Bell, K.Bell, K., Dunworth, E.A., Bulakh, A.G., Ivaniov, V.V.Terskii Coast, Russia: from kimberlite to carbonatite?Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p.RussiaCarbonatite, Terskii Coast
DS1994-0139
1994
Bell, K.Bell, K., Simonetti, A.Mantle signatures in carbonatitesGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p.MantleCarbonatite, Geophysics
DS1994-1608
1994
Bell, K.Simonetti, A., Bell, K.Isotopic and geochemical investigation of the Chilwa Island carbonatiteComplex, Malawi: evidence depleted..Journal of Petrology, Vol. 35, No. 6, Dec. pp. 1597-1622.MalawiCarbonatite, Geochemistry
DS1994-1609
1994
Bell, K.Simonetti, A., Bell, K.neodymium, lead and Strontium isotopic dat a from the Napak carbonatite-nephelinite eastern Uganda: an example of open system crystal fractionation.Contribution Mineralogy and Petrology, Vol. 116, No. 3, pp. 356-366.UgandaCarbonatite, Deposit -Napak
DS1994-1610
1994
Bell, K.Simonetti, A., Bell, K.neodymium, lead, and Strontium isotopic dat a from the Napak carbonatite-nephelinite eastern Uganda- an example of open system crystal fractionation.Contributions to Mineralogy and Petrology, Vol. 115, No.3, January pp. 356-366.UgandaCarbonatite, Geochronology
DS1994-1778
1994
Bell, K.Tilton, G.R., Bell, K.Strontium neodymium lead relationships in Late Archean carbonatites and alkaline complexes: applications geochemical evolution.Geochimica et Cosmochimica Acta, August pp. 3145-3154.CanadaCarbonatite, Geochronology, Archean mantle
DS1995-0135
1995
Bell, K.Bell, K., Keller, J.Carbonatite volcanism. #1Springer Verlag, 224p.approx. $ 140.00 United States ISBN 0-387-58299-1TanzaniaCarbonatite flows, Table of contents - Mantle metasomatism, Metasomatism, Oldoinyo Lengai area
DS1995-1758
1995
Bell, K.Simonetti, A., Bell, K.neodymium, lead and Strontium dat a from Mountain Elgon volcano, eastern UgAnd a -western Kenya:implications for origin lavasLithos, Vol. 36, No. 2, Nov. 1, pp. 141-Uganda, KenyaGeochronology, Nephelinite lavas
DS1995-1759
1995
Bell, K.Simonetti, A., Bell, K.neodymium, lead, and Strontium isotope systematics of fluorite at the Amba Dongar carbonatite Complex, India: fluid mixing...Economic Geology, Vol. 90, No. 7, Nov. pp. 2018-2027.IndiaCarbonatite, Geochronology, hydrotherma, crust, Deposit -Amba Dongar
DS1995-1760
1995
Bell, K.Simonetti, A., Bell, K.neodymium, lead, Strontium dat a from Mt. Elgon volcano, east UgAnd a -West Kenya-implications for evolution of nephelinitesLithos, Vol. 36, No.2, Nov. 1, pp. 141-Uganda, KenyaNephelinite
DS1995-1761
1995
Bell, K.Simonetti, A., Bell, K., Viladkar, S.G.Isotopic dat a from the Amba Donga carbonatite Complex, west-central India:evidence for enriched mantle sourceChemical Geology, Vol. 122, pp. 185-198.IndiaCarbonatite, geochronology, Deposit -Amba Donga
DS1995-2114
1995
Bell, K.Zaitsev, A., Bell, K.Strontium and neodymium isotopic dat a of apatite, calcite and dolomite as indicators of source and the relationsihipsContributions to Mineralogy and Petrology, Vol. 121, No. 3, pp. 324-335.Russia, Kola PeninsulaKovdor massif, Phoscorites, Carbonatite
DS1996-0109
1996
Bell, K.Bell, K., Dunworth, E.A., Bulakh, A.G., Ivanikov, V.V.Alkaline rocks of the Turiy Peninsula, Russia, including type localityturjaite and turjite: a reviewCanadian Mineralogist, Vol. 34, pt. 2, April pp. 265-280.RussiaAlkaline rocks, Petrology
DS1996-0110
1996
Bell, K.Bell, K., Simonetti, A.Carbonatitic magmatism and plume activity: implications from the neodymium lead and Sr isotope systematics of OldoinyoJournal of Petrology, Vol. 37, No. 6, Dec. pp. 1321-39.TanzaniaCarbonatite, Deposit -Oldoinyo Lengai
DS1996-1314
1996
Bell, K.Simonetti, A., Shore, M., Bell, K.Diopside phenocrysts from nephelinite lavas, Napak volcano, eastern Uganda:evidence for magma mixing.Canadian Mineralogist, Vol. 34, pt. 2, April pp. 411-422.UgandaAlkaline rocks, metamorphism
DS1997-0087
1997
Bell, K.Bell, K.Isotope systematics of carbonatites and related rocks- recent dat a and newdirections.Geological Association of Canada (GAC) Abstracts, GlobalCarbonatite, Geochronology
DS1997-0088
1997
Bell, K.Bell, K., Zaitsev, A.Chemistry and lead isotopic composition of galena from rare earth elements (REE) carbonatitesKola, Russia.Geological Association of Canada (GAC) Abstracts, POSTER.Russia, Kola PeninsulaCarbonatite
DS1997-0297
1997
Bell, K.Dunworth, E.A., Bell, K., Arzamastsev, A.A., Bulakh, A.Age relationships, isotopic disequilibrium and trace element characteristics of the Turily Massif.....Geological Association of Canada (GAC) Abstracts, POSTER.Russia, Kola PeninsulaCarbonatite, Terskii Coast pipes
DS1997-0298
1997
Bell, K.Dunworth, E.A., Bell, K., Bulakh, A.G., Ivanikov, V.V.The Turiy massif: the role of A1 coordination and major element partitioning in melilitolites, carbonatites...Geological Association of Canada (GAC) Abstracts, Russia, Kola PeninsulaCarbonatite
DS1997-0996
1997
Bell, K.Sasada, T., Hiyagon, H., Bell, K., Erihara, M.Mantle derived noble gases in carbonatitesGeochimica et Cosmochimica Acta, Vol. 61, No. 19, Oct. pp. 4219-28.Brazil, Ontario, QuebecCarbonatite, Jacupirigna, Tapira, Borden, Oka, Prairie, Poohbah
DS1997-1045
1997
Bell, K.Simonetti, A., Bell, K.Trace and rare earth element geochemistry of the June 1993 natrocarbonatitelavas, Oldoinyo Lengai....Journal of Volcanology and Geothermal Research, Vol. 75, No. 1-2, pp. 89-106.TanzaniaCarbonatite magmas, Deposit - Oldoinyo Lengai
DS1997-1287
1997
Bell, K.Zaitsev, A., Wall, F., Bell, K., Le Bas, M.Minerals from the Khibin a carbonatites, Kola Peninsula, their paragenesis and evolution.Geological Association of Canada (GAC) Abstracts, POSTER.Russia, Kola PeninsulaCarbonatite, Deposit - Khibina
DS1997-1288
1997
Bell, K.Zaitsev, A.N., Bell, K., Wall, F., Le Bas, M.J.Alkaline rare earth element carbonates from carbonatites of the KhibinyMassif: mineralogy, genesisDoklady Academy of Sciences, Vol. 355, No. 5, Jun-July pp. 786-90.RussiaCarbonatite
DS1998-0103
1998
Bell, K.Bell, K.Radiogenic isotope constraints on relationships between carbonatites and associated silicate rocks - review...Journal of Petrology, Vol. 39, No. 11-12, Nov-Dec. pp. 1987-96.East Africa, TanzaniaCarbonatite - geochronology, Review, Shombole, Oldoinyo Lengai
DS1998-0372
1998
Bell, K.Dunworth, E., Bell, K.Melilitolites: a new scheme of classificationCanadian Mineralogist, Vol. 36, No. 3, June pp. 895-903.GlobalPetrology - classification, Melilitolites - melilite
DS1998-0665
1998
Bell, K.Ivanikov, V.V., Rukhlov, A., Bell, K.Magmatic evolution of the melilitite carbonatite nephelinite dyke series Of the Turyi Peninsula.Journal of Petrology, Vol. 39, No. 11-12, Nov-Dec. pp. 2043-59.Russia, White Sea, Kadalaksha BayCarbonatite, melilitite, Dike swarm
DS2001-0099
2001
Bell, K.Bell, K.Carbonatites: relationships to mantle plume activityGeological Society of America Special Paper, Special Paper. 352, pp. 267-90.MantlePlumes, Carbonatite
DS2001-0100
2001
Bell, K.Bell, K., Simonetti, A.A close look at magma chamber dynamics - in situ Sr Sr measurements of igneous minerals from la MC ICP MS.Geological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p.12, abstract.Quebec, FinlandCarbonatite, strontium, Oka, Sillinjarvi
DS2001-0101
2001
Bell, K.Bell, K., Tilton, G.R.neodymium lead and Strontium isotopic compositions of East African carbonatites: evidence for mantle mixing and plume....Journal of Petrology, Vol. 42, No. 10, Oct. pp. 1927-46.TanzaniaPlumes - inhomogeneity, mantle plumes, Carbonatite
DS2001-0990
2001
Bell, K.Rukhlov, A., Bell, K., Ivanikov, V.Archean mantle below the Baltic Shield: isotopic evidence from intrusive carbonatites.Journal of South African Earth Sciences, Vol. 32, No. 1, p. A 30-1.(abs)Russia, Kola Peninsula, Baltic ShieldCarbonatite, Geochronology - data
DS2001-0991
2001
Bell, K.Rukhlov, A., Bell, K., Ivanikov, V.Kola carbonatites and carbonatites: glimpses into the sub-continental margiJournal of South African Earth Sciences, Vol. 32, No. 1, p. A 32-3.(abs)Russia, Kola Peninsula, Baltic ShieldCarbonatite, Geochronology - data
DS2002-0135
2002
Bell, K.Bell, K.Carbonatites and related alkaline rocks, lamprophyres, and kimberlites - indicators mantle plume activity.Role of Superplumes in the Earth System Interiors: Workshop on Earth Systems, 3p. abst.GlobalPlumes, hotspots
DS2003-0358
2003
Bell, K.Dunworth, E.A., Bell, K.The Turiy Massif, Kola Peninsula, Russia: mineral chemistry of an ultramafic alkalineMineralogical Magazine, Vol. 67, 3, pp. 423-52.Russia, Kola PeninsulaCarbonatite
DS2003-0957
2003
Bell, K.Mirnejad, H., Bell, K., Kjarsgaard, B.Sr and Nd isotopic geochemistry of pegmatoid lamproites from Walgidee Hills, westGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.325.AustraliaLamproite
DS200412-0492
2003
Bell, K.Dunworth, E.A., Bell, K.The Turiy Massif, Kola Peninsula, Russia: mineral chemistry of an ultramafic alkaline carbonatite intrusion.Mineralogical Magazine, Vol. 67, 3, pp. 423-52.Russia, Kola PeninsulaCarbonatite
DS200412-1331
2003
Bell, K.Mirnejad, H., Bell, K., Kjarsgaard, B.Sr and Nd isotopic geochemistry of pegmatoid lamproites from Walgidee Hills, west Kimberley, Australia.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.325.AustraliaLamproite
DS200712-0065
2006
Bell, K.Bell, K., Catorima, F., Rosatelli, G., Stoppa, F.Plume activity, magmatism, and the geodynamic evolution of the central Mediterranean.Annals of Geophysics, Vol. 49, pp. 357-371.EuropeMagmatism, hot spots
DS200712-0731
2006
Bell, K.Mirnejad, H., Bell, K.Origin and source evolution of the Leucite Hills lamproites: evidence from Sr Nd Pb O isotopic compositions.Journal of Petrology, Vol. 47, 12, pp. 2463-2489.United States, Wyoming, Colorado PlateauLamproite
DS200812-0018
2008
Bell, K.Ali, A., Nakai, S., Bell, K., Sahoo, Y.W isotope study of natrocarbonatites from Oldoinyo Lengai Tanzania.Goldschmidt Conference 2008, Abstract p.A15.Africa, TanzaniaCarbonatite
DS200812-0091
2008
Bell, K.Beard, B., Johnson, C., Bell, K.Iron isotope compositions of carbonatites record melt generation and late stage volatile loss processes.Goldschmidt Conference 2008, Abstract p.A62.MantleCarbonatite
DS200812-0340
2008
Bell, K.Farrell, S., Clark, I., Bell, K.Sulphur isotopes in carbonatites and associated silicate rocks from the Superior Province Canada.Goldschmidt Conference 2008, Abstract p.A258.Canada, OntarioCarbonatite
DS200812-0442
2008
Bell, K.Halama, R., McDonough, W.F., Rudnick, R.L., Bell, K.Tracking the lithium isotopic evolution of the mantle using carbonatites.Earth and Planetary Science Letters, Vol. 265, 3-4, Jan. 30, pp. 726-742.MantleCarbonatite
DS200812-0750
2008
Bell, K.Mirnejad, H., Bell, K.Geochemistry of crustal xenoliths from the Hatcher Mesa lamproite, Wyoming, USA: insights into the composition of the deep crust and upper mantle beneath the Wyoming craton.Canadian Mineralogist, Vol. 46, 3, pp. 583-596.United States, Wyoming, Colorado PlateauLamproite, craton
DS200912-0046
2009
Bell, K.Bell, K., Simonetti, A.Source of parental melts to carbonatites - critical isotopic constraints.Mineralogy and Petrology, in press availableGlobalMantle metamorphism
DS200912-0047
2009
Bell, K.Bell, K., Simonetti, A.Source of parental melts to carbonatites - critical isotopic constraints.Mineralogy and Petrology, In press available, 13p.MantleMelting - mantle metasomatism
DS200912-0206
2009
Bell, K.Ernst, R.E., Bell, K.Large igneous provinces (LIPs) and carbonatites.Mineralogy and Petrology, In press available, 22p.GlobalRift-carbonatite link
DS200912-0340
2009
Bell, K.Johnson, C.M., Bell, K., Beard, B.L., Shultis, A.J.Iron isotope compositions of carbonatites record melt generation, crystallization and late stage volatile transport processes.Mineralogy and Petrology, in press availableGlobalCarbonatite, geochronology
DS200912-0653
2009
Bell, K.Rukhlov, A.S., Bell, K.Geochronology of carbonatites from the Canadian and Baltic shields, and the Canadian Cordillera: clues to mantle evolution.Mineralogy and Petrology, in press availableCanada, Europe, Baltic ShieldMagmatism - carbonatites
DS201012-0047
2010
Bell, K.Bell, K., Simonetti, A.Source of parental melts to carbonatites - critical isotopic constraints.Mineralogy and Petrology, Vol. 98, 1-4, pp. 77-89.MantleCarbonatite
DS201012-0194
2010
Bell, K.Farrell, S., Bell, K., Clark, I.Sulphur isotopes in carbonatites and associated silicate rocks from the Superior Province, Canada.Mineralogy and Petrology, Vol. 98, 1-4, pp. 209-226.Canada, OntarioGeochronology
DS201012-0327
2010
Bell, K.Johnson, C.M., Bell, K., Benard, B.L.,Shultis, A.L.Iron isotope compositions of carbonatites record melt generation, crystallization and late stage volatile transport systems.Mineralogy and Petrology, Vol. 98, 1-4, pp. 91-110.MantleCarbonatite
DS201012-0642
2010
Bell, K.Rukhlov, A.S., Bell, K.Geochronology of carbonatites from the Canadian and Baltic Shields, and the Canadian Cordillera: clues to mantle evolution.Mineralogy and Petrology, Vol. 98, 1-4, pp. 11-54.Canada, EuropeCarbonatite
DS201112-0076
2010
Bell, K.Bell, K.Carbonatites, isotopes and mantle plumes - some comments.Vladykin, N.V., Deep Seated Magmatism: its sources and plumes, pp. 5-21.GlobalCarbonatite, petrology
DS201112-0077
2011
Bell, K.Bell, K.Carbonatites and Pb isotopes- insights into terrestrial evolution.Goldschmidt Conference 2011, abstract p.510.Canada, FennoscandiaGeochronology
DS201112-0403
2011
Bell, K.Halama, R., McDonough, W.F., Rudnick, R.L., Bell, K.The lithium isotopic signature of carbonatites.Goldschmidt Conference 2011, abstract p.965.MantleMagmatism
DS201506-0256
2015
Bell, K.Bell, K., Zaitsev, A.N., Spratt, J., Frojdo, S., Rukhlov, A.S.Elemental, lead and sulfur isotopic compositions of galena from Kola carbonatites, Russia - implications for melt and mantle evolution.Mineralogical Magazine, Vol. 79, 2, pp. 219-241.RussiaCarbonatite, Kola

Abstract: Galena from four REE-rich (Khibina, Sallanlatvi, Seblyavr, Vuoriyarvi) and REE-poor (Kovdor) carbonatites, as well as hydrothermal veins (Khibina) all from the Devonian Kola Alkaline Province of northwestern Russia was analysed for trace elements and Pb and S isotope compositions. Microprobe analyses show that the only detectable elements in galena are Bi and Ag and these vary from not detectable to 2.23 and not detectable to 0.43 wt.% respectively. Three distinct galena groups can be recognized using Bi and Ag contents, which differ from groupings based on Pb isotope data. The Pb isotope ratios show significant spread with 206Pb/204Pb ratios (16.79 to 18.99), 207Pb/204Pb (15.22 to 15.58) and 208Pb/204Pb ratios (36.75 to 38.62). A near-linear array in a 207Pb/204Pb vs. 206Pb/204Pb ratio diagram is consistent with mixing between distinct mantle sources, one of which formed during a major differentiation event in the late Archaean or earlier. The S isotopic composition (d34S) of galena from carbonatites is significantly lighter (–-6.7 to -–10.3% Canyon Diablo Troilite (CDT) from REE-rich Khibina, Seblyavr and Vuoriyarvi carbonatites, and - 3.2% CDT from REE-poor Kovdor carbonatites) than the mantle value of 0%. Although there is no correlation between S and any of the Pb isotope ratios, Bi and Ag abundances correlate negatively with d34S values. The variations in the isotopic composition of Pb are attributed to partial melting of an isotopically heterogeneous mantle source, while those of d34S (together with Bi and Ag abundances) are considered to be process driven. Although variation in Pb isotope values between complexes might reflect different degrees of interaction between carbonatitic melts and continental crust or metasomatized lithosphere, the published noble gas and C, O, Sr, Nd and Hf isotopic data suggest that the variable Pb isotope ratios are best attributed to isotopic differences preserved within a sub-lithospheric mantle source. Different Pb isotopic compositions of galena from the same complex are consistent with a model of magma replenishment by carbonatitic melts/fluids each marked by quite different Pb isotopic compositions.
DS201512-1962
2015
Bell, K.Rukhov, A.S., Bell, K., Amelin, Y.Carbonatites, isotopes and evolution of continental mantle: an overview.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 39-64.MantleCarbonatite
DS201604-0624
2016
Bell, K.Rukhhlov, A.S., Bell, K., Amelin, Y.Carbonatites, isotopes and evolution of the subcontinental mantle: an overview.GAC MAC Meeting Special Session SS11: Cratons, kimberlites and diamonds., abstract 1/4p.MantleCarbonatite
DS201908-1786
2019
Bell, K.Li, W-Y., Yu, H-M., Xu, J., Halama, R., Bell, K., Nan, X-Y., Huang, F.Barium isotopic composition of the mantle: constraints from carbonatites.Geochimica et Cosmochimica Acta, in press available doi.org/10.1016 / j.gca.2019.06.041 36p.Africa, Tanzania, Canada, East Africa, Europe, Germany, Greenlanddeposit - Oldoinyo Lengai

Abstract: To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar d137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in d137/134Ba values from -0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average d137/134Ba value of their mantle sources is estimated to be +0.04?±?0.06‰ (2SD, n?=?16), which is similar to the average value of +0.05?±?0.06‰ for mid-ocean ridge basalts. The lower d137/134Ba value of -0.08‰ in a Canadian sample and higher d137/134Ba values of +0.14‰ and?+?0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.
DS202006-0931
2020
Bell, K.Li, W-Ye., Yu, H-M., Xu, J., Halama, R., Bell, K., Nan, X-Y., Huang, F.Barium isotopic composition of the mantle: constraints from carbonatites.Geochimica et Cosmochimica Acta, Vol. 278, pp. 235-243. pdfAfrica, Tanzania, Canada, Europe, Germany, Greenlanddeposit - Oldoinyo Lengai

Abstract: To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar d137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in d137/134Ba values from -0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average d137/134Ba value of their mantle sources is estimated to be +0.04?±?0.06‰ (2SD, n?=?16), which is similar to the average value of +0.05?±?0.06‰ for mid-ocean ridge basalts. The lower d137/134Ba value of -0.08‰ in a Canadian sample and higher d137/134Ba values of +0.14‰ and?+?0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.
DS202007-1160
2020
Bell, K.Li, W-Y., Yu, H-M., Xu, J., Halama, R., Bell, K., Nan, X-Y., Huang, F.Barium isotopic composition of the mantle: constraints from carbonatites.Geochimica et Cosmochimica Acta, Vol. 278, pp. 235-243.Mantlecarbonatite

Abstract: To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar d137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in d137/134Ba values from -0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average d137/134Ba value of their mantle sources is estimated to be +0.04?±?0.06‰ (2SD, n?=?16), which is similar to the average value of +0.05?±?0.06‰ for mid-ocean ridge basalts. The lower d137/134Ba value of -0.08‰ in a Canadian sample and higher d137/134Ba values of +0.14‰ and?+?0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.
DS1991-0091
1991
Bell, K.R.Bell, K.R.Gold in carbonatitesGeological Association of Canada (GAC)/Mineralogical Association of Canada/Society Economic, Vol. 16, Abstract program p. A9Quebec, Tanzania, Ontario, Africa, Europe, IndiaCarbonatite, Gold
DS1991-0092
1991
Bell, K.R.Bell, K.R., Peterson, T.neodymium and Strontium isotope systematics of Shombole volcano, East-Africa, and the links between nephelinites, phonolites and carbonatitesGeology, Vol. 19, No. 6, June pp. 582-585TanzaniaGeochronology, Carbonatite
DS1994-0140
1994
Bell, M.Bell, M.Is our climate unstable?Earth, Vol. 3, No. 1, January pp. 24-31GlobalClimate, Overview for the layman
DS1986-0522
1986
Bell, P.M.Mao, H-K., Xu J., Bell, P.M.Geophysical experiments: Ruby and diamond fluorescence measurements at 0.2-0. 5 terapascals ( 2-5 megabars)Eos, Vol. 67, No. 16, April 22, p. 368. (abstract.)GlobalDiamond morphology
DS1986-0881
1986
Bell, P.M.Xu, J.A., Mao, H.K., Bell, P.M.high pressure ruby and diamond fluoresence: observations at 0.21 and 0.55terapascalScience, Vol. 232, June 13, pp. 1404-1406. also reviewed in EOSGlobalDiamond, Crystallography
DS1950-0127
1953
Bell, R.Bell, R.Occurrence of Diamonds in the Northern StatesPrecambrian., Vol. 26, No. 4, PP. 22-23.GlobalDiamond Occurrence
DS1998-0104
1998
Bell, R.E.Bell, R.E.Gravity gradiometryScientific American, June pp. 74-79GlobalGeophysics - gravity, Gradiometry
DS1999-0056
1999
Bell, R.E.Bell, R.E., Childers, V.A., Brozenam J.M.Airborne gravity and precise positioning for geologic applicationsJournal of Geophysical Research, Vol. 104, No. 7, July 10, pp. 15281-92.GlobalGeophysics - gravity, GPS
DS1999-0057
1999
Bell, R.S.Bell, R.S., Corbett, J.D.New perspectives from vintage geophysics for the State Line diamonddistrict.Geology and Mineral of Wyoming, Oct. 14, 15. abstract p. 28.Colorado, WyomingGeophysics, Deposit - Kelsey Lake
DS1996-0111
1996
Bell, S.Bell, S.Diamond hopeful poised to strike... Striker ResourcesAustralia's Mining Monthly, April pp. 35-40.AustraliaNews item, Striker Resources
DS1992-0723
1992
Bell, S.B.Holroyd, F., Bell, S.B.Raster GIS: models of raster encodingComputers and Geosciences, Vol. 18, No. 4, pp. 419-426GlobalComputers, Programs -Geographic information systems, raster encodi
DS1995-2075
1995
Bell, T.E.Woodward, L.A., Bell, T.E.Pre-Middle Cambrian (Proterozoic?) block faulting in central MontanaThe Mountain Geologist, Vol. 32, No. 4, Oct. pp. 107-112.MontanaStructure
DS1994-0141
1994
Bell, T.M.Bell, T.M., Whateley, M.K.G.Evaluation of grade estimation techniquesGeological Society of London Mineral Resource Evaluation II, No. 79, editor Whateley, Harvey pp. 67-86GlobalGeostatistics, ore reserves, economics, Grade estimation
DS200512-0075
2005
Bellahsen, N.Bellahsen, N., Faccenna, C., Funiciello, F.Dynamics of subduction and plate motion laboratory experiments: insight into the plate tectonics behaviour of the Earth.Journal of Geophysical Research, Vol. 110, B1, Jan. 6, B10401.MantleTectonics, subduction
DS201412-0003
2014
Bellahsen, N.Agard, P., Zuo, X., Funiciello, F., Bellahsen, N., Faccenna, C., Savva, D.Obduction: why, how and where. Clues from analog models.Earth and Planetary Science Letters, Vol. 393, pp. 132-145.MantleSubduction
DS2000-0625
2000
BellaicheMascle, J., Benkhelil, J., Bellaiche, Zitter, WoodsideMarine geologic evidence for a Levantine Sinai plate: a new piece of evidence of the Mediterranean puzzle.Geology, Vol. 28, No. 9, Sept. pp. 779-82.Africa, North AfricaTectonics
DS2000-0610
2000
Bellanger, E.Mandea, M., Bellanger, E., Le Mouel, J-L.A geomagnetic jerk for the end of the 20th. century?Earth and Planetary Science Letters, Vol.183, No.3-4, pp.369-73.GlobalGeophysics - magnetics
DS2003-0096
2003
Bellashen, N.Bellashen, N., Faccenna, C., Funiciello, F., Daniel, J.M., Jolivet, L.Why did Arabia separate from Africa? Insights from 3-D laboratory experimentsEarth and Planetary Science Letters, Vol. 216, 3, pp. 365-81.AfricaTectonics, rifting
DS200412-0131
2003
Bellashen, N.Bellashen, N., Faccenna, C., Funiciello, F., Daniel, J.M., Jolivet, L.Why did Arabia separate from Africa? Insights from 3-D laboratory experiments.Earth and Planetary Science Letters, Vol. 216, 3, pp. 365-81.AfricaTectonics, rifting
DS200712-0235
2007
Bellatreccia, F.Della Ventura, G., Bellatreccia, F., Piccinini, M.Water in leucite, a nominally anhydrous volcanic mineral.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 269.Europe, ItalyWater storage
DS200712-0236
2007
Bellatreccia, F.Della Ventura, G., Bellatreccia, F., Piccinini, M.Water in leucite, a nominally anhydrous volcanic mineral.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 269.Europe, ItalyWater storage
DS1998-0105
1998
Bellefleur, G.Bellefleur, G., Calvert, A.J., Chouteau, M.C.Crustal geometry of the Abitibi Subprovince, in light of three dimensional seismic reflector orientation.Canadian Journal of Earth Sciences, Vol. 35, No. 5, May pp. 569-82.Quebec, OntarioGeophysics - seismics, Tectonics
DS2003-0914
2003
Bellefleur, G.McGaughey, W.J., Perron, G., Bellefleur, G.Downhole seismic imaging technology for deep mineral exploration. (mentions VictorOntario Exploration and Geoscience Symposium, Dec. 8,9,10th., Abstracts p. 16-17. (1/4p.)Ontario, AttawapiskatGeophysics - seismic DS
DS200412-1271
2003
Bellefleur, G.McGaughey, W.J., Perron, G., Bellefleur, G.Downhole seismic imaging technology for deep mineral exploration. (mentions Victor pipe)Ontario Exploration and Geoscience Symposium, Dec. 8,9,10th., Abstracts p. 16-17. (1/4p.)Canada, Ontario, Attawapiskat, James Bay LowlandsGeophysics - seismic DS
DS200512-1012
2005
Bellefleur, G.Snyder, D., Bellefleur, G.Feasibility study for using high resolution seismic methods to estimate kimberlite deposit volumes at Snap Lake diamond mine, Northwest Territories.Geological Survey of Canada, Current Research 2005-C3, 11p.Canada, Northwest TerritoriesGeophysics - crosshole seismology, vibrating, radar
DS200712-0066
2005
Bellefleur, G.Bellefleur, G., Matthews, L., Roberts,B., McMonnies, B., Salisbury, M., Snyder, D., Perron, G., McGaughty, J.Downhole seismic imaging of the Victor kimberlite, James Bay Lowlands, Ontario: a feasibility study.Geological Survey of Canada Current Research, 2005- C1, 7p.Canada, OntarioGeophysics - seismics
DS1989-1158
1989
Bellefontaine, K.A.Owen, J.V., Greenough, J.D., Bellefontaine, K.A.Preservation of primary geochemical signatures in polymetamorphosedtholeite: the Long Range dyke swarm,Newfoundland, CanadaLithos, Vol. 24, No. 1, December pp. 55-64NewfoundlandTholeite, Long Range dyke swarm
DS1860-0220
1874
Belleville, A.Belleville, A.The Lydenburg Gold Fields, With Route from the Diamond FieldUnknown., MAP SCALE 1: 20 MILES.Africa, South Africa, Griqualand WestTravelogue
DS200912-0242
2009
Bellevre, M.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
DS200412-0669
2004
Belley, J.M.Girard, R., Parent,M., Aubin, A., Belley, J.M., Lalancette, J.Glacial dispersion of lithological indicators in the Otish Mountain area.Quebec Exploration Conference, Canada, Quebec, Otish MountainsGeochemistry, geomorphology
DS202002-0164
2020
Belley, P.M.Belley, P.M., Groat, L.A.Metamorphosed carbonate platforms and controls on the genesis of sapphire, gem spinel, and lapis Lazuli: insight from the Lake Harbour Group, Nunavut, Canada and implications for gem exploration.Ore Geology Reviews, Vol. 116, 10p. PdfCanada, Nunavutgemstones

Abstract: Baffin Island's Lake Harbour Group (LHG), a Paleoproterozoic granulite facies metasedimentary sequence rich in carbonates, contains occurrences of the gemstones sapphire (corundum), spinel (including vivid blue, cobalt-enriched spinel), and lapis lazuli (haüyne-bearing rock). Most occurrences of these gem minerals are uniquely metasedimentary (carbonates and calc-silicate rock), while a few spinel occurrences formed from metasomatic reactions between Si-Al-rich rock (syenogranite or gneiss) and marble. The metasedimentary corundum, spinel, and haüyne occurrences have similar protoliths: primarily dolomitic marls with a high Al/Si relative abundance (interpreted as sandy mud to clay siliciclastic fraction in the protolith). Kimmirut-type sapphire deposits formed via a multi-step metamorphic process under three different and specific P-T conditions. Lapis lazuli formation required the presence of evaporites to provide Na and possibly S for the blue mineral haüyne. In addition to high Al/Si calc-silicate rocks, spinel also occurs in impure dolomitic marbles with very low K/Al. Potential for Kimmirut-type sapphire deposits is expected to be restricted to metacarbonate sequences proximal to the thrust fault separating the LHG from the Narsajuaq Arc, where retrograde upper amphibolite facies mineralization is most pervasive. Spinel and Kimmirut-type sapphire deposits are expected to be found in dolomitic marble sequences rich in calc-silicate layers. The potential occurrence of lapis lazuli is more difficult to predict but deposits could be identified thanks to large geographical footprints and their color. Similar gem occurrences or deposits to those in the LHG may be found in other metacarbonate-bearing terranes with similar metamorphic conditions (and for Kimmirut-type sapphire, a similar metamorphic history). Aerial hyperspectral and photographic surveys are well-suited to gemstone exploration on southern Baffin Island thanks to excellent rock exposure with minimal sediment or plant/lichen cover. Spectral mapping of dolomite-, diopside-, phlogopite-, and scapolite-rich domains in LHG metacarbonate sequences using airborne hyperspectral data is expected to provide exploration targets. Remote sensing exploration could be used in other metacarbonate-bearing, upper amphibolite to granulite facies metamorphic terranes found in polar climates, arid climates, or at high elevation in mountainous regions where such rocks are well exposed with minimal vegetative cover.
DS1990-1181
1990
Bellieni, G.Piccirillo, E.M., Bellieni, G., Cavazzini, G., Comin-Chiaramonti, P.Lower Cretaceous tholeiitic dyke swarms from the Ponta Grossa ArchChemical Geology, Vol. 89, pp. 19-48BrazilBasaltic dykes, Mantle-peridotite
DS1992-0113
1992
Bellieni, G.Bellieni, G., Macedo, M.H.F., Petrini, R., Piccirillo, E.M.Evidence of magmatic activity related to Middle Jurassic and LowerChemical Geology, Vol. 97, No. 1/2, May 15, pp. 9-32BrazilTectonics, Geochronology
DS1995-0136
1995
Bellieni, G.Bellieni, G., Piccirillo, E.M., et al.Petrological and Strontium neodymium evidence bearing on early Proterozoic magmatic events of subcontinental mantleContributions to Mineralogy and Petrology, Vol. 122, No. 3, Dec. pp. 252-261.BrazilCraton -Sao Francisco, Geochronology
DS1995-0137
1995
Bellieni, G.Bellieni, G., Piccirillo, E.M., Tanner de Oliviera, M.A.Petrological and Sr-neodymium evidence bearing on Early Proterozoic magmatic events of the sub-cont. mantle..Contributions to Mineralogy and Petrology, Vol. 122, No. 3, pp. 252-261BrazilGeochronology, Craton -Sao Francisco
DS2003-0615
2003
Bellieni, G.Iacumin, M., DeMin, A., Piccirillo, E.M., Bellieni, G.Source mantle heterogeneity and its role in the genesis of Late Archean Proterozoic (Earth Science Reviews, Vol. 62, 3-4, pp. 365-397.South AmericaMagmatism
DS200412-0864
2003
Bellieni, G.Iacumin, M., DeMin, A., Piccirillo, E.M., Bellieni, G.Source mantle heterogeneity and its role in the genesis of Late Archean Proterozoic ( 2.7 - 1.0 Ga) and Mesozoic (200 and 130 MaEarth Science Reviews, Vol. 62, 3-4, pp. 365-397.South AmericaMagmatism
DS2003-1150
2003
Bellier, O.Regard, V., Faccenna, C., Martinod, J., Bellier, O., Thomas, J-C.From subduction to collision: control of deep processes on the evolution of convergentJournal of Geophysical Research, Vol. 108, B4. 10.1029/2002JB001943MantleSubduction, Tectonics
DS200412-1647
2003
Bellier, O.Regard, V., Faccenna, C., Martinod, J., Bellier, O., Thomas, J-C.From subduction to collision: control of deep processes on the evolution of convergent plate boundary.Journal of Geophysical Research, Vol. 108, B4. 10.1029/2002 JB001943MantleSubduction Tectonics
DS201605-0824
2016
Bellingan, P.Daniel, M.J., Bellingan, P., Rauscher, M.The modelling of scrubbers and AG mills in the diamond industry and when to use them.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 167-186.TechnologyMining - applied
DS201512-1926
2015
Bellinger, J.Hardman, M.F., Stachel, T., Pearson, D.G., Kinakin, Y.B., Bellinger, J.Improving the utility of eclogitic garnet in diamond exploration - examples from Lac de Gras and worldwide localities.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 47.Canada, Northwest TerritoriesGarnet chemistry

Abstract: In diamond exploration, the use of compositional data to identify diamond-related peridotitic xenocrysts has long been a widely used and powerful tool. In contrast, the application of similar methods to eclogitic garnet chemistry remains a challenge. The inability to unequivocally classify certain “eclogitic” garnet compositions as either mantle- or crust-derived implies that a high abundance of lower-crustal garnets will increase diamond-exploration expenditures by introducing a number of “false positives.” Revising existing classification schemes (e.g., Schulze, 2003) to reduce the abundance of “false positives” may, however, increase the number of “false negatives” through the misclassification of mantle-derived garnets as crustal. This study presents new geochemical and petrographical data for garnet and clinopyroxene from 724 kimberlite-hosted, crust- and mantle-derived xenoliths from localities worldwide, with a focus on samples whose lithology is constrained petrographically, rather than single mineral grains from concentrate. Mantle samples are primarily eclogitic and pyroxenitic, as constrained by mineral assemblage and garnet and clinopyroxene mineral chemistry, while crustal samples are dominantly plagioclase-bearing garnet-granulites. For those localities where an established geothermal gradient is available from literature resources, garnet-clinopyroxene pairs are employed in the estimation of pressure-temperature conditions of equilibration through the iterative coupling of the Krogh (1988) geothermometer and the relevant geothermal gradient. Our preliminary results suggest that closure temperatures for Fe-Mg exchange exceed the temperatures of residence of many lower-crustal samples, as geotherm-based calculated pressures of equilibration exceed the apparent stability of plagioclase (see Green and Ringwood, 1972). Comparison of equilibration pressures with sodium contents in garnet for mantle-derived samples (the diamond-facies criterion of Gurney, 1984) shows a positive correlation at localities for which an adequate range of pressures is observed (e.g., the Diavik mine). Other populations, such as mantle eclogitic garnets from Roberts Victor, plot at a much more restricted range of pressures and hence fail to demonstrate this correlation; instead, these samples may reflect the influence of a broader range of bulk-compositions, providing varying amounts of sodium to their constituent garnets. The results presented here demonstrate clearly that garnets from mantle- and crust-derived samples show significant overlap in geochemical character, for example in garnet Ca# vs. Mg# space (discrimination diagram of Schulze, 2003), where approximately 66% of our crust-derived garnet analyses plot in the “mantle” field. This percentage varies among locations. A selection of particularly high-Mg#, low-Ca# garnets derived from crustal, plagioclase-bearing lithologies in this study highlights the potential for crust-mantle confusion, as these garnets have Mg# in-excess of many mantle-derived eclogitic/pyroxenitic garnets. As a consequence, Fe-Mg-Ca-based classifications alone cannot reliably discriminate mantle and crustal garnets. The next step in this project will be to obtain trace element data for the entire sample suite. This will allow us to test the Li-geobarometer of Hanrahan et al. (2009) for eclogites and to search for trace element signatures that can be used as robust indicators of a diamond-facies origin of eclogitic garnets. Trace element data will also be employed in the refinement of the crust/mantle division discussed above.
DS1988-0574
1988
Bellion, Y.Ritz, M., Bellion, Y.Structure of the Senegalo-Mauritanian basin West Africa, from geoelectrical studiesTectonophysics, Vol. 148, No. 3/4, May 1, pp. 235-240West AfricaTectonics
DS200712-0067
2007
Bellis, A.Bellis, A., Canil, D.Ferric iron in Ca Ti Os perovskite as an oxygen barometer for kimberlitic magmas I. experimental calibration.Journal of Petrology, Vol. 48, 2, Feb., pp. 219-230.TechnologyKimberlite magmatism
DS200812-0099
2007
Bellis, A.Bellis, A., Canil, D.Ferric iron in CaTiO perovskite as an oxygen barometer for kimberlite magmas. 1. experimental calibration.Journal of Petrology, Vol. 48, pp. 219-230.TechnologyBarometer
DS200912-0786
2009
Bellis, A.Van Rythoven, A., McCandless, T.E., Schulze, D.J.,Bellis, A., Taylor, I.A., Liu, Y.In-situ analysis of diamonds and their mineral inclusions from the Lynx kimberlite dyke complex, central Quebec.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyCanada, QuebecDeposit - Lynx
DS201112-1077
2011
Bellis, A.Van Rythoven, A.D., McCandless, T.E., Schulze, D.J., Bellis, A., Taylor, L.A., Liu, Y.Diamond crystals and their mineral inclusions from the Lynx kimberlite dyke complex, central Quebec.The Canadian Mineralogist, Vol. 49, 3, pp. 691-706.Canada, QuebecDiamond morphology - Lynx dyke
DS200712-0142
2007
Bellis, A.J.Canil, D., Bellis, A.J.Ferric iron in Ca Ti Os perovskite as an oxygen barometer for kimberlitic magmas II. applications.Journal of Petrology, Vol. 48, 2, Feb., pp. 231-252.TechnologyKimberlite magmatism
DS200812-0179
2008
Bellis, A.J.Canil, D., Bellis, A.J.Phase equilibration temperatures in a volatile free kimberlite at 0.1 MPa and the search for primary kimberlite magma.Lithos, Vol. 105, pp. 111-117.TechnologyKimberlite - phase equilibria, magma
DS1986-0064
1986
Bellizzia, G.A.Bellizzia, G.A.Mineral resources of Venezuela 1986Agid News, Vol. 47, pp. 22-25VenezuelaBrief mention of diamonds
DS1989-1153
1989
Bello, A.Onugba, A., Bello, A., Ajakaiye, D.E.Resistivity and seismic refraction survey of the Masari/Kafur Kimberlite pipe in northern Nigeria ( and its groundwater reserves)Journal of African Earth Sciences, Vol. 9, No. 2, pp. 235-243NigeriaGeophysics, Seismics
DS201412-0048
2014
Bello, L.Bello, L., Coltice, N., Rolf, T., Tackley, P.J.On the predictability limit of convection models of the Earth's mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, 6, pp. 2319-2328.MantleConvection
DS1988-0693
1988
Bellon, H.Tiercelin, J.J., Chorowicz, J., Bellon, H., Richert, J.P., et al.East African rift system: offset, age and tectonic significance of the Tanganyika-Rukwa -Malawi intracontinental transcurrent fault zoneTectonophysics, Vol. 148, No. 3/4, May 1, pp. 241-252East AfricaBlank
DS1991-1923
1991
Bellon, H.Zeilinga de Boer, J., Defant, M.J., Stewart, R.H., Bellon, H.Evidence for active subduction below western PanamaGeology, Vol. 19, No. 6, June pp. 649-652GlobalGeochronology, Geophysics
DS2002-0331
2002
Bellon, H.Coulon, C., Megartsi, M., Fourcade, S., Maury, R.C., Bellon, H., Louni Hacini, A.Post collisional transition from calc-alkaline to alkaline volcanism during the Neogene inLithos, Vol.62,3-4,pp. 87-110.AlgeriaSubduction - slab
DS201012-0037
2010
Bellon, H.Bardintzeff, J-M., Ligeois, J-P., Bonin, B., Bellon, H., Rasamimana, G.Madagascar volcanic provinces linked to the Gondwana break-up: geochemical isotopic evidences for contrasting mantle sources.Gondwana Research, Vol. 18, 2-3, pp. 295-314.Africa, MadagascarGeochronology
DS201412-0204
2014
Bellot, N.Doucelance, R., Bellot, N., Boyet, M., Hammouda, T., Bosq, C.What coupled cerium and neodynium isotopes tell us about the deep source of oceanic carbonatites.Earth and Planetary Science Letters, Vol. 407, pp. 175-195.Europe, Cape Verde Islands, Africa, MoroccoCarbonatite
DS1991-0093
1991
Bellotti, M.J.Bellotti, M.J., Dershowitz, W.Hydrogeological investigations: dat a and information managementComputers and Geosciences, Vol. 17, No. 8, pp. 1119-1136GlobalComputers, Program -hydrogeological
DS201112-0078
2011
Bellucci, J.J.Bellucci, J.J., McDonough, W.F., Rudnick, R.L.Thermal history and origin of the Tanzanian Craton from Pb isotope thermochronology of feldspars from lower crustal xenoliths.Earth and Planetary Science Letters, Vol. 301, 3-4, pp. 493-501.Africa, TanzaniaGeothermometry
DS201112-0369
2011
Bellucci, P.Giehl, C., Bellucci, P., Nguyen, H-T., Marks, M., Nowak, M.Experimental investigation of the differentiation of iron rich peralkaline magma.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologyMagmatism
DS201608-1418
2016
Belluco, L.Kueter, N., Soesilo, J., Fedortchouk, Y., Nestola, F., Belluco, L., Troch, J., Walle, M., Giuillong, M., Von Quadt, A., Driesner, T.Tracing the depositional history of Kalimantan diamonds by zircon provenance and diamond morphology studies. ( kimberlite or lamproite)Lithos, in press availableIndonesia, BorneoDeposit - Kalimantan

Abstract: Diamonds in alluvial deposits in Southeast Asia are not accompanied by indicator minerals suggesting primary kimberlite or lamproite sources. The Meratus Mountains in Southeast Borneo (Province Kalimantan Selatan, Indonesia) provide the largest known deposit of these so-called “headless” diamond deposits. Proposals for the origin of Kalimantan diamonds include the adjacent Meratus ophiolite complex, ultra-high pressure (UHP) metamorphic terranes, obducted subcontinental lithospheric mantle and undiscovered kimberlite-type sources. Here we report results from detailed sediment provenance analysis of diamond-bearing Quaternary river channel material and from representative outcrops of the oldest known formations within the Alino Group, including the diamond-bearing Campanian-Maastrichtian Manunggul Formation. Optical examination of surfaces of diamonds collected from artisanal miners in the Meratus area (247 stones) and in West Borneo (Sanggau Area, Province Kalimantan Barat;
DS201707-1342
2017
Belluco, L.Kueter, N., Soesilo, J., Fedortchouk, Y., Nestola, F., Belluco, L., Troch, J., Walle, M., Guillong, M., Von Quadt, A., Driesner, T.Tracing the depositional history of Kalimantan diamonds by zircon proveneance and diamond morphology studies. Appendix 1 and 2Academia.edu, Supplementary material app. 1 and 2, both 10p.Asia, Kalimantandeposit - Kalimantan

Abstract: Diamonds in alluvial deposits in Southeast Asia are not accompanied by indicator minerals suggesting primary kimberlite or lamproite sources. The Meratus Mountains in Southeast Borneo (Province Kalimantan Selatan, Indonesia) provide the largest known deposit of these so-called “headless” diamond deposits. Proposals for the origin of Kalimantan diamonds include the adjacent Meratus ophiolite complex, ultra-high pressure (UHP) metamorphic terranes, obducted subcontinental lithospheric mantle and undiscovered kimberlite-type sources. Here we report results from detailed sediment provenance analysis of diamond-bearing Quaternary river channel material and from representative outcrops of the oldest known formations within the Alino Group, including the diamond-bearing Campanian–Maastrichtian Manunggul Formation. Optical examination of surfaces of diamonds collected from artisanal miners in the Meratus area (247 stones) and in West Borneo (Sanggau Area, Province Kalimantan Barat; 85 stones) points toward a classical kimberlite-type source for the majority of these diamonds. Some of the diamonds host mineral inclusions suitable for deep single-crystal X-ray diffraction investigation. We determined the depth of formation of two olivines, one coesite and one peridotitic garnet inclusion. Pressure of formation estimates for the peridotitic garnet at independently derived temperatures of 930–1250 °C are between 4.8 and 6.0 GPa. Sediment provenance analysis includes petrography coupled to analyses of detrital garnet and glaucophane. The compositions of these key minerals do not indicate kimberlite-derived material. By analyzing almost 1400 zircons for trace element concentrations with laser ablation ICP-MS (LA-ICP-MS) we tested the mineral's potential as an alternative kimberlite indicator. The screening ultimately resulted in a small subset of ten zircons with a kimberlitic affinity. Subsequent U–Pb dating resulting in Cretaceous ages plus a detailed chemical reflection make a kimberlitic origin unfavorable with respect to the regional geological history. Rather, trace elemental analyses (U, Th and Eu) suggest an eclogitic source for these zircons. The age distribution of detrital zircons allows in general a better understanding of collisional events that formed the Meratus orogen and identifies various North Australian Orogens as potential Pre-Mesozoic sediment sources. Our data support a model whereby the majority of Kalimantan diamonds were emplaced within the North Australian Craton by volcanic processes. Partly re-deposited into paleo-collectors or residing in their primary host, these diamond-deposits spread passively throughout Southeast Asia by terrane migration during the Gondwana breakup. Terrane amalgamation events largely metamorphosed these diamond-bearing lithologies while destroying the indicative mineral content. Orogenic uplift finally liberated their diamond-content into new, autochthonous placer deposits.
DS1997-0346
1997
Belluso, E.Ferraris, G., Khomyakov, A.P., Belluso, E., Soboleva, S.Polysomatic relationships in some titanosilicates occurring in the hyperagpaitic alkaline rocks Kola Pen.Proceedings 30th. I.G.C., Pt. 16, pp. 17-27.Russia, Kola PeninsulaAlkaline rocks
DS1930-0015
1930
Belmont, L.Belmont, L., Parmentier, A.Les Champs Diamantiferes du Kasai dans Leurs Rapports Avec La Geologie de la Region. - the Diamondiferous Fields of Kasai and Geological reports.International Geological Congress 6TH., Vol. 1, PP. 17-24.Democratic Republic of Congo, Central AfricaGeology, Distribution
DS201112-1096
2011
Belmonte, L.J.Vulic, P., Balic-Zunic, T., Belmonte, L.J., Kahlenberg, V.Crystal chemistry of nephelines from ijolites and nepheline rich pegmatites: influence of composition and genesis on the crystal structure investigated by X-ray diffraction.Mineralogy and Petrology, Vol. 101, 3-4, pp. 185-194.MantleIjolite
DS1992-0973
1992
Belo de Oliveira, O.Machado, N., Noce, C.M., Ladeira, E.A., Belo de Oliveira, O.uranium-lead (U-Pb) (U-Pb) geochronology of Archean magmatism and Proterozoic metamorphism in the Quadrilatero Ferrifero, southern Sao Francisco craton, BrasilGeological Society of America (GSA) Bulletin, Vol. 104, No. 9, September pp. 1221-1227BrazilGeochronology, Proterozoic
DS1995-0138
1995
Beloborodov, V.H.Beloborodov, V.H., Isakov, A.L., Kramshov, N.P., Sher, E.N.Behaviour of crystals in kimberlite and ice under the action of shockwaves.Journal of Min. Science, Vol. 31, No. 2, Mar-Apr. pp. 109-113. #TB408RussiaKimberlite petrography
DS201505-0249
2015
Belogub, E.V.Belogub, E.V., Krivovichev, S.V., Pekov, I.V., Kuznetsov, A.M., Yapaskurt, V.O., Kitlyarov, V.A., Chukanov, N.V., Belakoviskiy, D.I.Nickelpicromerite, K2Ni(SO4)2*6H2O, a new picromerite group mineral from Slyudorudnik, South Urals, Russia.Mineralogy and Petrology, Vol. 109, 2, pp. 143-152.Russia, UralsMineralogy

Abstract: A new picromerite-group mineral, nickelpicromerite, K2Ni(SO4)2 - 6H2O (IMA 2012-053), was found at the Vein #169 of the Ufaley quartz deposit, near the town of Slyudorudnik, Kyshtym District, Chelyabinsk area, South Urals, Russia. It is a supergene mineral that occurs, with gypsum and goethite, in the fractures of slightly weathered actinolite-talc schist containing partially vermiculitized biotite and partially altered sulfides: pyrrhotite, pentlandite, millerite, pyrite and marcasite. Nickelpicromerite forms equant to short prismatic or tabular crystals up to 0.07 mm in size and anhedral grains up to 0.5 mm across, their clusters or crusts up to 1 mm. Nickelpicromerite is light greenish blue. Lustre is vitreous. Mohs hardness is 2-2½. Cleavage is distinct, parallel to {10-2}. Dmeas is 2.20(2), Dcalc is 2.22 g cm-3. Nickelpicromerite is optically biaxial (+), a = 1.486(2), ß = 1.489(2), ? = 1.494(2), 2Vmeas =75(10)°, 2Vcalc =76°. The chemical composition (wt.%, electron-microprobe data) is: K2O 20.93, MgO 0.38, FeO 0.07, NiO 16.76, SO3 37.20, H2O (calc.) 24.66, total 100.00. The empirical formula, calculated based on 14 O, is: K1.93Mg0.04Ni0.98S2.02O8.05(H2O)5.95. Nickelpicromerite is monoclinic, P21/c, a = 6.1310(7), b = 12.1863(14), c = 9.0076(10) Å, ß = 105.045(2)°, V = 649.9(1) Å3, Z = 2. Eight strongest reflections of the powder XRD pattern are [d,Å-I(hkl)]: 5.386--34(110); 4.312-46(002); 4.240-33(120); 4.085--100(012, 10-2); 3.685-85(031), 3.041-45(040, 112), 2.808-31(013, 20-2, 122), 2.368-34(13-3, 21-3, 033). Nickelpicromerite (single-crystal X-ray data, R = 0.028) is isostructural to other picromerite-group minerals and synthetic Tutton’s salts. Its crystal structure consists of [Ni(H2O)6]2+ octahedra linked to (SO4)2- tetrahedra via hydrogen bonds. K+ cations are coordinated by eight anions. Nickelpicromerite is the product of alteration of primary sulfide minerals and the reaction of the acid Ni-sulfate solutions with biotite.
DS1996-0112
1996
Belolipetskii, A.P.Belolipetskii, A.P., Voloshin, A.V.Yttrium and rare earth element minerals of the Kola Peninsula, RussiaMineralogical Soc. Series, No. 7, pp. 311-326.RussiaRare earth minerals, Kola Peninsula
DS1989-0465
1989
Belomesnyy, A.B.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
DS1989-0464
1989
Belomestnykh, A.V.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
DS1990-0509
1990
Belomestnykh, A.V.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
DS200612-0912
2005
Belonos, I.V.Metelkin, D.V., Vernikovksy, V.A., Lazanskii, A.Yu., Belonos, I.V.The Siberian Craton in the structure of the supercontinent Rodinia: analysis of paleomagnetic data.Doklady Earth Sciences, Vol. 404, 7, pp. 1021-1026.RussiaTectonics, geophysics - paleomagnetism
DS2003-0097
2003
Belonoshko, A.B.Belonoshko, A.B., Ahuja,k R., Johannson, B.Stability of the body centered cubic phase of iron in the Earth's inner coreNature, No. 6952, August 28, pp. 1032-4.MantleGeochemistry
DS200412-0132
2003
Belonoshko, A.B.Belonoshko, A.B., Ahuja,k R., Johannson, B.Stability of the body centered cubic phase of iron in the Earth's inner core.Nature, No. 6952, August 28, pp. 1032-4.MantleGeochemistry
DS200512-1002
2005
Belonoshko, A.B.Skorodumova, N.V., Belonoshko, A.B., Huang, L., Ahuja, R., Johansson, B.Stability of the MgCO3 structures under lower mantle conditions.American Mineralogist, Vol.90, pp. 1008-1011.MantleCarbon, Liquid outer core, boundary
DS200712-0068
2007
Belonoshko, A.B.Belonoshko, A.B.Origin of the low rigidity of the Earth's Inner core.Science, Vol. 316 5831 June 15, pp. 1603-1605.MantleCore
DS200712-0069
2007
Belonoshko, A.B.Belonoshko, A.B.Origin of the low rigidity of the Earth's Inner core.Science, Vol. 316 5831 June 15, pp. 1603-1605.MantleCore
DS200812-0100
2008
Belonoshko, A.B.Belonoshko, A.B.Elastic anisotropy of Earth's inner core.Science, Vol. 319, 5864, pp. 797-799.MantleIron - anisotropy
DS1983-0131
1983
Beloshitskii, V.V.Beloshitskii, V.V., Bykovskii, Y.A., et al.Electromagnetic Radiation of Quasichanneling PositronsRadiation Effects, Vol. 76, No. 3, PP. 93-100.GlobalExperimental Studies, Mineralogy
DS1990-0328
1990
Belouov, I.S.Chipenko, G.V., Ivakhnen, S.A., Kvasnits.. V, N., Belouov, I.S.A new habitus type of diamond crystal.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 312, No. 4, pp. 876-879GlobalDiamond morphology, Crystallography
DS200712-0773
2007
BelouovaNasir, S., Al-Khirbashi, S., Al-Sayigh, Alharthy, Mubarek, Rollinson, Lazki, Belouova, Griffin, KaminskyThe first record of allochthonous kimberlite within the Batain Nappes, eastern Oman.Plates, Plumes, and Paradigms, 1p. abstract p. A706.Africa, OmanBatain melange
DS200812-0787
2008
BelousaNasir, S., Al-Khirbash, Rollinson, Al-Harthy, Al-Sayigh, Al-Lazki, Belousa, Kaminsky, Theye, Massone, Al-BuaidiEvolved carbonatitic kimberlite from the Batain Nappes, eastern Oman continental margin.9IKC.com, 3p. extended abstractAfrica, Arabia, OmanPetrography
DS200812-0788
2008
BelousaNasir, S., Al-Khirbash, Rollinson, Al-Harthy, Al-Sayigh, Al-Lazki, Belousa, Kaminsky, Theye, Massone, Al-BuaidiLate Jurassic Early Cretaceous kimberlite, carbonatite and ultramafic lamprophyric sill and dyke swarms from the Bomethra area, northeastern Oman.9IKC.com, 3p. extended abstractAfrica, Arabia, OmanPetrography
DS200812-0089
2008
Belousa, E.A.Batumike, J.M., Griffin, W.L., Belousa, E.A., Pearson, N.J., O'Reilly, S.Y., Shee, S.R.LAM-ICPMS U-Pb dating of kimberlite perovskite: Eocene-Oligocene kimberlites from the Kundelungu Plateau D.R. Congo.Earth and Planetary Science Letters, Vol. 267, 3-4, pp.609-619.Africa, Democratic Republic of CongoGeochrononoloy - Kundelungu
DS2000-1040
2000
BelousobaYatsenko, G.M., Panov, Belousoba, Lesnov, GriffinThe rare earth elements (REE) distribution in zircon from minettes of the Kirovograd Ukraine.Doklady Academy of Sciences, Vol. 370, No. 1, Jan-Feb pp.196-200.Russia, UkraineGeochronology, Minettes
DS1994-0142
1994
Belousov, T.P.Belousov, T.P., et al.First find of mantle xenoliths in igneous rocks of the greater caucasusDoklady Academy of Sciences Acad. Science USSR, Vol. 324, No. 4, July pp. 86-91.RussiaXenoliths
DS1992-0114
1992
Belousov, V.V.Belousov, V.V.Structure of the crust and upper mantle of the former USSRInternational Geology Review, Vol. 34, No. 3, March pp. 213-338RussiaTectonics Table of contents available, Structure
DS2002-1531
2002
BelousovaSpetius, Z.V., Belousova, Griffin, O'Reilly, PearsonArchean sulphide inclusions in Paleozoic zircon megacrysts from the Mir kimberlite: implications datingEarth and Planetary Science Letters, Vol.199,1-2,pp.111-26., Vol.199,1-2,pp.111-26.Russia, YakutiaGeochronology - dating of diamonds, Deposit - Mir
DS2002-1532
2002
BelousovaSpetius, Z.V., Belousova, Griffin, O'Reilly, PearsonArchean sulphide inclusions in Paleozoic zircon megacrysts from the Mir kimberlite: implications datingEarth and Planetary Science Letters, Vol.199,1-2,pp.111-26., Vol.199,1-2,pp.111-26.Russia, YakutiaGeochronology - dating of diamonds, Deposit - Mir
DS201012-0500
2010
BelousovaMints, M.V., Konilov, A.N., Dokukina, Kaulina, Belousova, Natapov, Griffin, O'ReillyThe Belomorian eclogite province: unique evidence of Meso-Neoarchean subduction and collisionsDoklady Earth Sciences, Vol. 434, 2, pp. 1311-1316.RussiaEclogite
DS201012-0528
2010
BelousovaNasir, S., Al-Khirbash, S., Rollinson, Al-Harthy, Al-Sayigh, Al-Lazki, A., Theye, T.Massonne, BelousovaPetrogenesis of early Cretaceous carbonatite and ultramafic lamprophyres in a diatreme in the Batain Nappes, eastern Oman continental margin.Contributions to Mineralogy and Petrology, in press available, 28p.Africa, OmanCarbonatite
DS201112-0724
2011
BelousovaNasir, S., Al-Khirbash, S., Rollinson, H., Al-Harthy, Al-Sayigh, Al-Lazki, Theye, Massonne, BelousovaPetrogenesis of early Cretaceous carbonatite and ultramafic lamprophyres in a diatreme in the Batain Nappes, eastern Oman continental margin.Contributions to Mineralogy and Petrology, Vol. 161, 1, pp. 47-74.Asia, OmanCarbonatite
DS201312-0506
2013
BelousovaKosler, J., Slama, Belousova, Corfu, Gehrels, Gerdes, Horstwood, Sircombe, Sylvester, Tiepolo, Whitehouse, WoodheadU-Pb detrital zircon analysis - results of an inter-laboratory comparison. (not specific to diamonds)Geostandards and Geoanalytical Research, Vol. 37, 3, pp. 243-259.GlobalZircon analyses
DS1998-0106
1998
Belousova, E.Belousova, E., Griffin, W.L., O'Reilly, S.Y.Apatite: a sensitive indicator of crystallization environmentGemoc 1998 Annual Report, p. 20. abstractNorway, South Africa, Russia, AustraliaCarbonatite
DS200512-0743
2005
Belousova, E.Moore, A., Belousova, E.Crystallization of Cr poor and Cr rich megacrysts suites from the host kimberlite magma: implications for mantle structure and generation of kimberlite magmas.Contributions to Mineralogy and Petrology, On lineMantleMagma - kimberlite
DS200712-0823
2006
Belousova, E.Pearson, D.J., O'Reilly, S.Y., Griffin, W.L., Alard, O., Belousova, E.Linking crustal and mantle events using in situ trace element and isotope analysis.Geochimica et Cosmochimica Acta, In press availableMantleGeochronology
DS200812-1292
2008
Belousova, E.Yang, J-H, Wu, F-Y., Wilde, S.A., Belousova, E., Griffin, W.L.Mesozoic decratonization of the North Chin a block.Geology, Vol. 36, 6, June pp. 467-470.ChinaCraton
DS200912-0041
2009
Belousova, E.Begg, G., Belousova, E., Griffin, W.L., O'Reilly, S.Y., Natapov, L.Continental versus crustal growth: resolving the paradox.Goldschmidt Conference 2009, p. A103 Abstract.MantleArchean - Boundary
DS200912-0048
2009
Belousova, E.Belousova, E., Kostitsyn, Y.A., Griffin, W.L., O'Reilly, S.Y.Testing models for continental crustal growth: a TerraneChron approach.Goldschmidt Conference 2009, p. A107 Abstract.MantleDatabase
DS201112-0079
2000
Belousova, E.Belousova, E.Zircon and apatite geochemistry: applications to petrology and mineral exploration.Thesis: Macquarie University Phd. , Thesis: note availability based on request to author
DS201112-0202
2011
Belousova, E.Condie, K.C., Bickford, M.E., Aster, R.C., Belousova, E., Scholl, D.W.Episodic zircon ages, Hf isotopic composition, and the preservation rate of continental crust.Geological Society of America Bulletin, Vol.l 123, pp. 951-957.MantleGeochronology
DS201201-0851
2011
Belousova, E.Kahoui, M., Kemainsky, F.V., Griffin, W.L., Belousova, E., Mahdjoub, Y., Chabane, M.Detrital pyrope garnets from the El Kseibat area, Algeria: a glimpse into the lithospheric mantle beneath the north-eastern edge of the West African Craton.Journal of African Earth Sciences, In press available, 46p.Africa, AlgeriaGeochemistry - El Kseibat
DS201212-0119
2012
Belousova, E.Chalapathi Rao, N.V., Lehmann, B., Belousova, E., Frei, D., Mainkar, D.Petrology, bulk rock geochemistry, indicator mineral composition and zircon U-Pb geochronology of the end Cretaceous Diamondiferous Mainpur orangeites, Bastar Craton, Central India.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractIndiaDeposit - Mainpur
DS201212-0346
2012
Belousova, E.Kahoui, M., Kaminsky, F.V., Griffin, W.L., Belousova, E., Mahdjoub, Y., Chabane, M.Detrital pyrope garnets from the El Kseibat area, Algeria: a glimpse into lithospheric mantle beneath the north eastern edge of the west African Craton.Journal of African Earth Sciences, Vol. 63, Feb. pp. 1-11.AfricaEglab shield
DS201312-0454
2012
Belousova, E.Kaminsky, F.V., Kahoui, M.,Mahdjoub, Y., Belousova, E., Griffin, W.L.,O'Reilly, S.Y.Pyrope garnets from the Eglab Shield, Algeria: look inside the Earth's mantle in the West African Craton and suggestions about primary sources of diamond and indicator minerals.Vladykin, N.V. ed. Deep seated magmatism, its sources and plumes, Russian Academy of Sciences, pp. 73-103.Africa, AlgeriaMineralogy
DS201412-1006
2013
Belousova, E.Yaxley, G.M., Kamenetsky, V.S., Nichols, G.T., Maas, R., Belousova, E., Rosenthal, A., Norman, M.The discovery of kimberlites in Antarctica extends the vast Gondwanan Cretaceous province.Nature Communications, Dec. 17, 7p.AntarcticaPrince Charles Mountains
DS201604-0597
2016
Belousova, E.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
Belousova, E.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.
DS201711-2514
2017
Belousova, E.Gonzalez-Jimenez, J.M., Camprubi, A., Colas, V., Griffin, W.L., Proenza, J.A., O'Reilly, S.Y., Centeno-Garcia, El., Garcia-Casco, A., Belousova, E., Talavera, C., Farre-de-Pablo, J., Satsukawa, T.The recycling of chromitites in ophiolites from southwestern North America. ( Baja)Lithos, in press available, 52p.United States, Californiachromitites

Abstract: Podiform chromitites occur in mantle peridotites of the Late Triassic Puerto Nuevo Ophiolite, Baja California Sur State, Mexico. These are high-Cr chromitites [Cr# (Cr/Cr + Al atomic ratio = 0.61-0.69)] that contain a range of minor- and trace-elements and show whole-rock enrichment in IPGE (Os, Ir, Ru). That are similar to those of high-Cr ophiolitic chromitites crystallised from melts similar to high-Mg island-arc tholeiites (IAT) and boninites in supra-subduction-zone mantle wedges. Crystallisation of these chromitites from S-undersaturated melts is consistent with the presence of abundant inclusions of platinum-group minerals (PGM) such as laurite (RuS2)-erlichmanite (OsS2), osmium and irarsite (IrAsS) in chromite, that yield TMA ˜ TRD model ages peaking at ~ 325 Ma. Thirty-three xenocrystic zircons recovered from mineral concentrates of these chromitites yield ages (2263 ± 44 Ma to 278 ± 4 Ma) and Hf-O compositions [?Hf(t) = - 18.7 to + 9.1 and 18O values < 12.4‰] that broadly match those of zircons reported in nearby exposed crustal blocks of southwestern North America. We interpret these chromitite zircons as remnants of partly digested continental crust or continent-derived sediments on oceanic crust delivered into the mantle via subduction. They were captured by the parental melts of the chromitites when the latter formed in a supra-subduction zone mantle wedge polluted with crustal material. In addition, the Puerto Nuevo chromites have clinopyroxene lamellae with preferred crystallographic orientation, which we interpret as evidence that chromitites have experienced high-temperature and ultra high-pressure conditions (< 12 GPa and ~ 1600 °C). We propose a tectonic scenario that involves the formation of chromitite in the supra-subduction zone mantle wedge underlying the Vizcaino intra-oceanic arc ca. 250 Ma ago, deep-mantle recycling, and subsequent diapiric exhumation in the intra-oceanic basin (the San Hipólito marginal sea) generated during an extensional stage of the Vizcaino intra-oceanic arc ca. 221 Ma ago. The TRD ages at ~ 325 Ma record a partial melting event in the mantle prior to the construction of the Vizcaino intra-oceanic arc, which is probably related to the Permian continental subduction, dated at ~ 311 Ma.
DS201906-1293
2019
Belousova, E.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.
DS1998-0107
1998
Belousova, E.A.Belousova, E.A., Griffin, W.L., O'Reilly, S.Y.Trace element composition and cathodluminescence properties of kimberliticzircons.7th International Kimberlite Conference Abstract, pp. 67-69.South Africa, Russia, Yakutia, AustraliaMineralogy - trace elements, Zircons
DS1998-0108
1998
Belousova, E.A.Belousova, E.A., Griffin, W.L., Pearson, N.J.Trace element composition and cathodluminescence properties of Southern african kimberlitic zircons.Mineralogical Magazine, Vol. 62, No. 3, June pp. 355-66.South AfricaDiamond inclusions, Mineral chemistry
DS2001-0102
2001
Belousova, E.A.Belousova, E.A., Griffin, W.L., Shee, Jackson, O'ReillyTwo age populations of zircons from the Timber Creek kimberlites, as determined by laser ablation ICP MSAustralian Journal of Earth Sciences, Vol. 48, No. 5, Oct. pp. 757-766.AustraliaGeochronology, Deposit - Timber Creek
DS2002-0136
2002
Belousova, E.A.Belousova, E.A., Griffin, W.L., O'Reilly, S.Y., Fisher, N.I.Apatite as an indicator mineral for mineral exploration: trace element compositions and their relationship to host rock type.Journal of Geochemical Exploration, Vol.76,1,July pp. 45-69.MantleGeochemistry - indicator minerals
DS2002-0137
2002
Belousova, E.A.Belousova, E.A., Griffin, W.L., O'Reilly, S.Y., Fisher, N.I.Igneous zircon: trace element composition as an indicator of source rock typeContributions to Mineralogy and Petrology, Vol. 143, 5, pp.587-601.MantleUHP, Geochemistry - indicator minerals
DS2003-1261
2003
Belousova, E.A.Shchukin, V.S., Sablukov, S.M., Sablukova, L.I., Belousova, E.A., Griffin, V.L.Late Vendian aerial alkaline volcanism in the Winter Coast kimberlite area, Arkangelsk8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractRussia, ArkangelskKimberlite geology and economics, Deposit - Winter Coast
DS200412-0720
2004
Belousova, E.A.Griffin, W.L., Belousova, E.A., Shee, S.R., Pearson, N.J., O'Reilly, S.Y.Archean crustal evolution in the northern Yilgarn Craton: U Pb and Hf isotope evidence from detrital zircons.Precambrian Research, Vol. 131, 3-4, pp. 231-282.AustraliaGeochronology - Yilgarn
DS200512-0972
2002
Belousova, E.A.Shchukin, V.S., Sablukova, S.M., Sablukova, L.I., Belousova,E.A., Griffin, W.L.Late Vendian aerial alkaline volcanism of rift type in the Zimny Bereg kimberlite area, Arkangelsk Diamondiferous province.Deep Seated Magmatism, magmatism sources and the problem of plumes., pp. 203-212.Russia, Kola Peninsula, ArchangelAlkalic
DS200612-0116
2006
Belousova, E.A.Belousova, E.A., Reid, A.J., Griffin, W.L., O'Reilly, S.Y.Proterozoic rejuvenation of the Archean crust tracked by U Pb and hf isotopes in detrital zircon.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.AustraliaGeochronology
DS200612-0117
2006
Belousova, E.A.Belousova, E.A.,Griffin, W.L., O'Reilly, S.Y.Zircon crystal morphology, trace element signatures and Hf isotope composition as a tool for petrogenetic modelling: examples from eastern Australian granitoids.Journal of Petrology, Vol. 47, 2, pp. 329-325.AustraliaGeochronology - not specific to diamonds
DS200612-0500
2006
Belousova, E.A.Griffin, W.L., Pearson, N.J., Belousova, E.A., Saeed, A.Hf isotope heterogeneity in zircon 91500.... comment.Chemical Geology, Vol. 233, 3-4, Oct. 15, pp. 358-363.TechnologyGeochronology
DS200612-1475
2006
Belousova, E.A.Veevers, J.J., Belousova, E.A., Saced, A., Sircombe, K., Cooper, A.F., Read, S.E.Pan-Gondwanaland detrital zircons from Australia analyzed for Hf isotopes and trace elements reflect an ice covered Antartic provenance 700-500 Ma alkalinityEarth Science Reviews, in press,AustraliaGeochronology, trace elements
DS200612-1476
2006
Belousova, E.A.Veevers, J.J., Belousova, E.A., Saeed, A., Sircombe, K., Cooper, A.F., Read, S.E.Pan Gondwanaland detrital zircons from Australia analysed for Hf isotopes and trace elements reflect an ice covered Antarctic provenance of 700-500 Ma ...Earth Science Reviews, Vol. 76, 3-4, June pp. 135-174.AustraliaGeochronology, alkaline affinity
DS200712-0056
2007
Belousova, E.A.Batumike, J.M., O'Reilly, S.Y., Griffin, W.L., Belousova, E.A.U Pb and Hf isotope analyses of zircon from the Kundelungu kimberlites, D.R. Congo: implications for crustal evolution.Precambrian Research, Vol. 156, 3-4, pp. 195-225.Africa, Democratic Republic of CongoDeposit - geochronology - Kundelungu
DS200712-0057
2007
Belousova, E.A.Batumike, J.M., O'Reilly, S.Y., Griffin, W.L., Belousova, E.A.U Pb and Hf isotope analyses of zircon from the Kundelungu kimberlites, DRC: implications for crustal evolution.Precambrian Research, Vol. 156, 3-4, pp. 195-225.Africa, Democratic Republic of CongoKundelungu - geochronology
DS200812-0071
2008
Belousova, E.A.Babu, E.V.S.S.K., Griffin, W.L., Mukherjee, A., O'Reilly, S.Y., Belousova, E.A.Combined U Pb and Lu Hf analysis of megacrystic zircons from the Kalyandurg 4 kimberlite pipe, S. India: implications for the emplacement age and HF isotopic..9IKC.com, 3p. extended abstractIndiaGeochronology - cratonic mantle
DS200812-0101
2008
Belousova, E.A.Belousova, E.A., Kaminsky, F.V., Griffin, W.L.U Pb and Hf isotope and trace element composition of zircon megacrysts from the Juin a kimberlites, Brazil.Goldschmidt Conference 2008, Abstract p.A71.South America, Brazil, Mato GrossoDeposit - Pandrea
DS200812-0241
2008
Belousova, E.A.Cooper, S.A., Belousova, E.A., Griffin, W.L., Morris, B.J.Age of FS66 kimberlite beneath Murray Basin South Australia: laser ablation ICP MS dating of kimberlite zircon, perovskite and rutile.9IKC.com, 3p. extended abstractAustraliaDeposit FS66 geochronology
DS200812-0829
2008
Belousova, E.A.O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., Jackson, S.E., Belousova, E.A., Alard, O., Saeed, A.Taking the pulse of the Earth: linking crustal and mantle events.Australian Journal of Earth Sciences, Vol. 55, pp. 983-995.MantleGeochronology
DS200912-0038
2009
Belousova, E.A.Batumike, J.M., Griffin, W.L., O'Reilly, S.Y., Belousova, E.A., Palitschek, M.Crustal evolution in the central Congo -Kasai Craton, Luebo, D.R. Congo: insights from zircon U Pb ages, Hf isotope and trace element data.Precambrian Research, Vol. 170, 1-2, pp. 107-115.Africa, Democratic Republic of CongoGeochronology
DS200912-0049
2009
Belousova, E.A.Belousova, E.A., Reid, A.J., Griffin, W.L., O'Reilly, S.Y.Rejuvenation vs recycling of Archean crust in the Gawler Craton, south Australia: evidence from U Pb and Hf isotopes in detrital zircon.Lithos, In press - available 52p.AustraliaGeochronology
DS200912-0355
2009
Belousova, E.A.Kaminsky, F.V., Belousova, E.A.Manganoan ilmenite as kimberlite/diamond indicator mineral.Russian Geology and Geophysics, Vol. 50, pp. 1212-1220.South America, BrazilJuina placer diamonds
DS200912-0357
2009
Belousova, E.A.Kaminsky, F.V., Sablukov, S.M., Belousova, E.A., Andreazza, P., Tremblay, M., Griffin, W.L.Kimberlite sources of super deep diamonds in the Juin a area, Mato Grosso State, Brazil.Lithos, In press available,South America, Brazil, Mato GrossoKimberlite genesis
DS200912-0470
2009
Belousova, E.A.Malkovets, V.G., Belousova, E.A., Griffin, W.L., Buzlukova, L.V., Shatsky, V.S., O'Reilly, S.Y., Pokhilenko, N.P.U/Pb dating of zircons from the lower crustal xenoliths from Siberian kimberlites.Goldschmidt Conference 2009, p. A823 Abstract.Russia, SiberiaDeposit - Udachnaya
DS201012-0048
2010
Belousova, E.A.Belousova, E.A., Kostitsyn, Y.A., Griffin, W.L., Begg, G.C., O'Reilly, S.Y.The growth of the continental crust: constraints from zircon Hf isotope data.Lithos, Vol. 119, pp. 457-466.MantleGeochronology
DS201012-0341
2010
Belousova, E.A.Kaminsky, F.V., Sablukov, S.M., Belousova, E.A., Andreazza, P., Tremblay, M., Griffin, W.L.Kimberlitic sources of super deep diamonds in the Juin a area, Mato Grosso State, Bahia.Lithos, Vol. 114, pp. 16-29.South America, Brazil, Mato GrossoChapadao, Padrea
DS201012-0499
2010
Belousova, E.A.Mints, M.V., Belousova, E.A., Konilov, A.N., Natapov, Shchipansky, Griffin, O'Reilly, Dokukina, KaulinaMesoarchean subduction processes: 2.87 Ga eclogites from the Kola Peninsula, Russia.Geology, Vol. 38, 8, pp. 739-742.Russia, Kola PeninsulaBelomorian
DS201112-0197
2011
Belousova, E.A.Collins, W.J., Belousova, E.A., Kemp, A.I.S., Murphy, J.B.Two contrasting Phanerozoic orogenic systems revealed by hafnium isotope data.Nature Geoscience, Vol. 4, pp. 333-335.MantleConvection
DS201112-0730
2011
Belousova, E.A.Nedosekova, I.L., Belousova, E.A., Sharygin, V.V.Sources for the Il'meno Vishnevogorsky alkaline complex: evidence from the Lu-Hf isotopic dat a for zircons.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 205-212.RussiaAlkalic
DS201112-0945
2011
Belousova, E.A.Shatsky, V.S., Malkovets, V.G., Buzlukova, L., Griffin, W.L., Belousova, E.A., O'Reilly, S.Y.Deep crust of the Siberian craton evidence from xenolith.Goldschmidt Conference 2011, abstract p.1850.RussiaUdachnaya, Leningradskaya, Yubileynaya
DS201112-0991
2011
Belousova, E.A.Spetsius, Z.V., Belousova, E.A., Griffin, W.L., O'Reilly, S.Y., Ivanov, A.S.Zircon from kimberlites of the Nyurbinskaya pipe as indicator of kimberlite emplacement and lithosphere evolution.Goldschmidt Conference 2011, abstract p.1922.RussiaNakynsky
DS201212-0513
2012
Belousova, E.A.Nedosekova, I.L., Belousova, E.A., Sharygin, V.V., Belyatsky, B.V., Bayanova, T.B.Origin and evolution of the Ilmeny-Visnevogorsky carbonatites (Urals, Russia): insights from trace element compositions, and Rb-Sr, Sm-Nd, U-Pb, Lu-Hf isotope data.Mineralogy and Petrology, in press availableRussiaCarbonatite
DS201212-0514
2012
Belousova, E.A.Nedosekova, I.L., Belousova, E.A., Sharygin, V.V., Belyatsky, B.V., Bayanova, T.B.Origin and evolution of the Ilmeny Vishnevogorsky carbonatites ( Urals, Russia): insights from trace element compositions and Rb Sr, Sm Nd, U Pb, Lu Hf isotope data.Mineralogy and Petrology, in press availableRussiaCarbonatite
DS201312-0336
2013
Belousova, E.A.Griffin, W.L., Belousova, E.A., O'Neill, C., O'Reilly, S.Y., Malkovets, V., Pearson, N.J., Spetsius, S., Wilde, S.A.The world turns over: Hadean-Archean crust mantle evolution.Lithos, Vol. 189, pp. 2-15.MantleCrust- mantle review
DS201312-0641
2013
Belousova, E.A.Nedosekova, I.L., Belousova, E.A., Sharygin, V.V., Belyatsky, B.V.,Bayanova, T.B.Origin and evolution of the Ilmeny-Vishnevogorsky carbonatites ( Urals, Russia): insights from trace element compositions, and Rb Sr Sm Nd, U Pb, Lu Hf isotope data.Mineralogy and Petrology, Vol. 107, 1, pp. 101-123.Russia, UralsCarbonatite
DS201412-0438
2014
Belousova, E.A.Kamenetsky, V.S., Belousova, E.A., Giuliani, A., Kamenetsky, M.B., Goemann, K., Griffin, W.L.Chemical abrasion of zircon and ilmenite megacrysts in the Monastery kimberlite: implications for the composition of kimberlite melts.Chemical Geology, Vol. 383, pp. 76-85.Africa, South AfricaDeposit - Monastery
DS201412-0618
2014
Belousova, E.A.Nedosekova, I.L., Belousova, E.A., Belyatsky, B.V.Trace element and isotopes Hf as a signature of zircon genesis during evolution of alkaline carbonatite magmatic system ( Ilmeny Vishnevogorsky complex, urals, Russia.)30th. International Conference on Ore Potential of alkaline, kimberlite and carbonatite magmatism. Sept. 29-, http://alkaline2014.comRussia, UralsCarbonatite
DS201506-0287
2015
Belousova, E.A.Nedosekova, I.L., Belousova, E.A., Belyatsky, B.V.Hf isotopes and trace elements as indicators of zircon genesis in the evolution of the alkaline-carbonatite magmatic system ( Il'meno-Visnevogorskii complex, Urals, Russia.)Doklady Earth Sciences, Vol. 461, 2, pp. 384-389.Russia, UralsCarbonatite
DS201512-1938
2015
Belousova, E.A.Malich, K.N., Khiller, V.V., Badanina, I.Yu., Belousova, E.A.Results of dating of thorianite and badeleyite from carbonatites of the Guli massif, Russia.Doklady Earth Sciences, Vol. 464, 2, pp. 1029-1032.RussiaCarbonatite

Abstract: The isotopic -geochronological features of thorianite and baddeleyite from carbonatites of the Guli massif, located within Maimecha -Kotui province in the north of the Siberian Platform, are characterized for the first time. The economic complex platinum-group element (PGE) and gold placer deposits are closely related to the Guli massif. Similar geochronological data for thorianite (250.1 ± 2.9 Ma, MSWD = 0.09, n = 36) and baddeleyite (250.8 ± 1.2 Ma, MSWD = 0.2, n = 6) obtained by two different methods indicate that carbonatites were formed close to the Permian -Triassic boundary and are synchronous with tholeiitic flood basalts of the Siberian Platform.
DS201606-1090
2016
Belousova, E.A.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?
DS201610-1886
2016
Belousova, E.A.Melkovets, V.G., Rezvukhin, D.I., Belousova, E.A., Griffin, W.L., Sharygin, I.S., Tretiakova, I.G., Pokhilenko, N.P., Sobolev, N.V.Cr-rich rutile: a powerful tool for diamond exploration.Lithos, in press available 8p.Russia, SiberiaDeposit - Internationalnaya

Abstract: Mineralogical studies and U-Pb dating have been carried out on rutile included in peridotitic and eclogitic garnets from the Internatsionalnaya pipe, Mirny field, Siberian craton. We also describe a unique peridotitic paragenesis (rutile + forsterite + enstatite + Cr-diopside + Cr-pyrope) preserved in diamond from the Mir pipe, Mirny field. Compositions of rutile from the heavy mineral concentrates of the Internatsionalnaya pipe and rutile inclusions in crustal almandine-rich garnets from the Mayskaya pipe (Nakyn field), as well as from a range of different lithologies, are presented for comparison. Rutile from cratonic mantle peridotites shows characteristic enrichment in Cr, in contrast to lower-Cr rutile from crustal rocks and off-craton mantle. Rutile with Cr2O3 > 1.7 wt% is commonly derived from cratonic mantle, while rutiles with lower Cr2O3 may be both of cratonic and off-cratonic origin. New analytical developments and availability of standards have made rutile accessible to in situ U-Pb dating by laser ablation ICP-MS. A U-Pb age of 369 ± 10 Ma for 9 rutile grains in 7 garnets from the Internatsionalnaya pipe is consistent with the accepted eruption age of the pipe (360 Ma). The equilibrium temperatures of pyropes with rutile inclusions calculated using Ni-in-Gar thermometer range between ~ 725 and 1030 °C, corresponding to a depth range of ca ~ 100-165 km. At the time of entrainment in the kimberlite, garnets with Cr-rich rutile inclusions resided at temperatures well above the closure temperature for Pb in rutile, and thus U-Pb ages on mantle-derived rutile most likely record the emplacement age of the kimberlites. The synthesis of distinctive rutile compositions and U-Pb dating opens new perspectives for using rutile in diamond exploration in cratonic areas.
DS201612-2320
2016
Belousova, E.A.Malkovets, V.G., Rezvukhin, D.I., Belousova, E.A., Griffin, W.L., Sharygin, I.S., Tretiakov, I.G., Gibsher, A.A., O'Reilly, S.Y., Kuzmin, D.V., Litasov, K.D., Logvinova, A.M., Pokhilenko, N.P., Sobolev, N.V.Cr-rich rutile: a powerful tool for diamond exploration.Lithos, Vol. 265, pp. 304-311.Russia, SiberiaDeposit - Internationalskaya

Abstract: Mineralogical studies and U-Pb dating have been carried out on rutile included in peridotitic and eclogitic garnets from the Internatsionalnaya pipe, Mirny field, Siberian craton. We also describe a unique peridotitic paragenesis (rutile + forsterite + enstatite + Cr-diopside + Cr-pyrope) preserved in diamond from the Mir pipe, Mirny field. Compositions of rutile from the heavy mineral concentrates of the Internatsionalnaya pipe and rutile inclusions in crustal almandine-rich garnets from the Mayskaya pipe (Nakyn field), as well as from a range of different lithologies, are presented for comparison. Rutile from cratonic mantle peridotites shows characteristic enrichment in Cr, in contrast to lower-Cr rutile from crustal rocks and off-craton mantle. Rutile with Cr2O3 > 1.7 wt% is commonly derived from cratonic mantle, while rutiles with lower Cr2O3 may be both of cratonic and off-cratonic origin. New analytical developments and availability of standards have made rutile accessible to in situ U-Pb dating by laser ablation ICP-MS. A U-Pb age of 369 ± 10 Ma for 9 rutile grains in 6 garnets from the Internatsionalnaya pipe is consistent with the accepted eruption age of the pipe (360 Ma). The equilibrium temperatures of pyropes with rutile inclusions calculated using Ni-in-Gar thermometer range between ~ 725 and 1030 °C, corresponding to a depth range of ca ~ 100-165 km. At the time of entrainment in the kimberlite, garnets with Cr-rich rutile inclusions resided at temperatures well above the closure temperature for Pb in rutile, and thus U-Pb ages on mantle-derived rutile most likely record the emplacement age of the kimberlites. The synthesis of distinctive rutile compositions and U-Pb dating opens new perspectives for using rutile in diamond exploration in cratonic areas.
DS201701-0