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SDLRC - Scientific Articles all years by Author - R-Rh


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 - R-Rh
Posted/
Published
AuthorTitleSourceRegionKeywords
DS1990-1483
1990
R.Turek, A. Keller, R.uranium-lead (U-Pb) zircon ages of volcanism and plutonism in the Mishibishu Greenstone belt near Wawa.Canadian Journal of Earth Sciences, Vol. 27, pp. 649-56.OntarioGeochronology, Wawa area
DS1997-0210
1997
R.Conticelli, S., Francala, L., Manetti, P. Cioni, R.Petrology and geochemistry of the ultrapotassic rocks from the SabatiniJournal of Volcanology, Vol. 75, No. 1-2 Jan. pp. 107-136.ItalyUltrapotassic, Magma
DS1989-1248
1989
Raab, G.A.Raab, G.A., Enwall, R.E., Cole, W.H., Kuharic, C.A., Duggan, J.S.Fast analysis of heavy metals in contaminated soils using field -portable X-ray fluorescence technology and geostatisticsPreprint from Northwest Mining Association 95th. Annual Meeting held Dec., 19pGlobalGeostatistics, X-ray fluorescence Heavy metals
DS2002-1294
2002
Raab, M.J.Raab, M.J., Brown, R.W., Gallagherm K., Carter, A., Weber, K.Late Cretaceous reactivation of major crustal shear zones in northern Namibia: constraints from apatite fission track analysis.Tectonophysics, Vol. 349, No. 1-4, pp.75-92.NamibiaGeochronology, Tectonics
DS1983-0527
1983
Raab, P.Raab, P., Moss, C., Abrams, G.Aeromagnetic Dat a from Southeastern MissouriUnited States Geological Survey (USGS) GD 83-004, DOI/DF 83-005., GlobalMid Continent
DS1987-0600
1987
Raade, G.Raade, G.Davanite K2TiSi6O15 in the Smoky Butte (Montana) Lamproites.Discussion of X-ray powder dataAmerican Mineralogist, Vol. 72, pp. 1014-1015MontanaLamproite
DS1950-0421
1958
Raal, F.A.Raal, F.A.A New Absorption Band in Diamond and Its Likely CauseProceedings of THE PHYSICAL SOCIETY, Vol. 71, No. 461, PP. 846-847.GlobalDiamond Morphology
DS1960-1194
1969
Raal, F.A.Raal, F.A.De Beers Research Serves the Diamond IndustryJohannesburg: De Beers Mining Corporation Limited., 39P.South AfricaKimberlite
DS1988-0559
1988
Rabalais, J.W.Rabalais, J.W., Kasi, S.R.Process for the deposition of diamond filmsPatent: PCT International Appl. 88 10321 Al Dec. 29, 1988 77p, GlobalDiamond Application, Patent
DS1989-0883
1989
Rabalais, J.W.Lifshitz, Y., Kasi, S.R., Rabalais, J.W.Subplantation model for film growth from hypersthermal species-application to diamondPhys. Rev. L., Vol. 62, No. 11, March 13, pp. 1290-1293GlobalDiamond morphology
DS201212-0611
2012
Rabassa, J.Rutter, N., Coronato, A.,Helmens, K., Rabassa, J., Zarate, M.Glaciations in North and South America from the Miocene to the last glacial maximum.Springer, Book adUnited States, Canada, South AmericaGeomorphology
DS200612-1497
2006
Rabatho, J.Waanders, F., Rabatho, J.Recovery of heavy minerals by means of ferrosilicon dense medium separation material.Hyperfine Interactions, Vol. 161, 1-4, Feb. pp. 55-60.TechnologyDMS diamond recovery
DS200612-1498
2006
Rabatho, J.Waanders, F., Rabatho, J.Recovery of heavy minerals by means of ferrosilicon dense medium separation material.Hyperfine Interactions, Vol. 161, 1-4, Feb. pp. 55-60.TechnologyMining
DS200612-0903
2006
Rabbel, W.Meissner, R., Rabbel, W., Kern, H.Seismic lamination and anisotropy of the Lower Continental Crust.Tectonophysics, Vol. 416, 1-4, April 5, pp. 81-99.MantleGeophysics - seismics
DS200612-0904
2006
Rabbel, W.Meissner, R., Rabbel, W., Kern, H.Seismic lamination and anisotropy of the Lower Continental Crust.Tectonophysics, in pressMantle, Europe, GermanyGeophysics - seismics, crust mantle boundary
DS1991-1392
1991
Rabe, J.P.Rabe, J.P., Buchholz, S.Commensurability and mobility in two dimensional molecular patterns ongraphiteScience, Vol. 253, July 26, pp. 424-427GlobalMineralogy, Graphite
DS1995-0894
1995
Rabe, R.Jones, A.P., Taniguchi, T., Dobson, D., Rabe, R., MilledgeExperimental nucleation and growth of diamond from carbonate-graphitesystems.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 269-270.GlobalPetrology -experimental, Diamond nucleation
DS1975-0841
1978
Raber, E.Raber, E.Zircons from Diamond Bearing Kimberlites: Oxide Reactions, Fission Track dating and a Mineral Inclusion Study.Amherst: Msc. Thesis, University Massachusetts, GlobalGeochronology, Mineral Chemistry
DS1975-1189
1979
Raber, E.Raber, E., Haggerty, S.E.Zircon-oxide Reactions in Diamond Bearing KimberlitesProceedings of Second International Kimberlite Conference, Proceedings Vol. 1, PP. 229-240.South AfricaMineralogy
DS1983-0274
1983
Raber, E.Haggerty, S.E., Raber, E., Naeser, C.W.Fissure Track Dating of Kimberlitic ZirconsEarth Plan. Sci. Letters, Vol. 63, No. 1, PP. 41-50.South Africa, Botswana, Angola, Tanzania, Wyoming, State LineGeochronology, Kimberley Pool, Orapa, Val Do Queve, Koffiefontein
DS201902-0309
2019
Rabesandratana, T.Rabesandratana, T.Will the world embrace plan S, the radical proposal to mandate open access to science papers?Science,, Jan 3, 3p.Globalopen access papers

Abstract: How far will Plan S spread? Since the September 2018 launch of the Europe-backed program to mandate immediate open access (OA) to scientific literature, 16 funders in 13 countries have signed on. That's still far shy of Plan S's ambition: to convince the world's major research funders to require immediate OA to all published papers stemming from their grants. Whether it will reach that goal depends in part on details that remain to be settled, including a cap on the author charges that funders will pay for OA publication. But the plan has gained momentum: In December 2018, China stunned many by expressing strong support for Plan S. This month, a national funding agency in Africa is expected to join, possibly followed by a second U.S. funder. Others around the world are considering whether to sign on. Plan S, scheduled to take effect on 1 January 2020, has drawn support from many scientists, who welcome a shake-up of a publishing system that can generate large profits while keeping taxpayer-funded research results behind paywalls. But publishers (including AAAS, which publishes Science) are concerned, and some scientists worry that Plan S could restrict their choices.
DS1960-0379
1963
Rabhkin, M.I.Milashev, V.A., Krutoyarski, M.A., Rabhkin, M.I., Ehrlich, E.N.Kimberlitic Rocks and Picritic Porphyries of the North Eastern Part of the Siberian PlatformNiiga., Gosgeoltekizdat., Vol. 126, PP. 1-10.5.RussiaMineral Chemistry
DS202004-0504
2020
Rabinovich, O.IChernykh, S.V., Chernykh, A.V., Tarelkin, S., Didenko, S. ,Kondakov, M.N., Shcherbachev, K.D., Trifonova, E.V., Drozdova, T.E., Troschiev, S.Y., Prikhodko, D.D., Glybin, Y.N., Chubenko, A.P., Britvich, G.I., Kiselev, D.A., Polushin, N.I., Rabinovich, O.IHPHT single crystal diamond type IIa characterization for particle detectors.Physicsa Status Solidi , doi:10.1002/pssa.201900888GlobalHPHT

Abstract: Various samples of multisectoral high-pressure high-temperature (HPHT) single-crystal diamond plate (IIa type) (4?×?4?×?0.53?mm) are tested for particle detection applications. The samples are investigated by X-ray diffractometry, photoluminescence spectroscopy, Raman spectroscopy, Fourier-transform infrared, and visible/ultraviolet (UV) absorption spectroscopy. High crystalline perfection and low impurity concentration (in the {100} growth sector) are observed. To investigate detector parameters, circular 1.0 and 1.5?mm diameter Pt Schottky barrier contacts are created on {111} and {100} growth sectors. On the backside, a Pt contact (3.5?×?3.5?mm) is produced. The {100} growth sector is proved to be a high-quality detector: the full width at half maximum energy resolution is 0.94% for the 5.489?MeV 226Ra a-line at an operational bias of +500?V. Therefore, it is concluded that the HPHT material {100} growth sector is used for radiation detector production, whose quality is not worse than the chemical vapor deposition method or specially selected natural diamond detectors.
DS1988-0473
1988
Rabinowicz, M.Mimouni, A., Rabinowicz, M.The old continental shields stability related to mantle convectionGeophysical Research Letters, Vol. 15, No. 1, January pp. 68-71GlobalBlank
DS1993-0230
1993
Rabinowicz, M.Ceuleneer, G., Monnereau, M., Rabinowicz, M., Rosemberg, C.Thermal and petrological consequences of melt migration within mantleplumesPhilosophical Transactions Royal Society of London, Section A, Vol. 342, pp. 53-64MantleGeochemistry, plume model, Alkaline rocks
DS2000-0246
2000
Rabinowicz, M.Dubuffet, F., Rabinowicz, M., Monnereau, M.Multiple scales in mantle convectionEarth and Planetary Science Letters, Vol. 178, No. 3-4, May 30, pp. 351-66.MantleSubduction, Convection
DS2002-1295
2002
Rabinowicz, M.Rabinowicz, M., Ricard, Y., Gregoire, M.Compaction in a mantle with a very small melt concentration: implications for theEarth and Planetary Science Letters, Vol. 203, 1, pp. 205-220.MantleMagmatism, Carbonatite, Geochemistry
DS200612-1086
2006
Rabinowicz, M.Petitjean, S., Rabinowicz, M., Gregoire, M., Chevrot, S.Differences between Archean and Proterozoic lithospheres: assessment of the possible major role of thermal conductivity.Geochemistry, Geophysics, Geosystems: G3, Vol. 7, Q03021 10.1029/2005 GC001053MantleGeothermometry
DS200712-0894
2007
Rabinowicz, M.Richard, G., Monnereau, M., Rabinowicz, M.Slab dehydration and fluid migration at the base of the upper mantle: implications for deep earthquake mechanisms.Geophysical Journal International, Vol. 168, 3, pp. 1291-1304.MantleSlab melting
DS202105-0785
2021
Rabinowitz, Y.Rabinowitz, Y., Etinger, A., Litvak, B., Yahalom, A., Cohen, H., Pinhasi, Y.Millimeter wave spectroscopy for evaluating diamond color grades.Diamond & Related Materials, Vol. 116, 108386 10p. PdfGlobalspectroscopy

Abstract: One of the most important parameters affecting the value of natural colorless diamonds is its light transparency, defined as its color grade. The regular range of color grades in the trade is denoted by alphabet letters in the range D-M, where D represents the best commercial quality. The color grade of diamonds is largely influenced by their nitrogen content (when nitrogen atoms substitute carbon atoms in the crystal) and can be determined from this property. Diamonds absorb electromagnetic radiation in the UV-visible as well as in the Infrared spectral range and therefore, their color grade is measured via spectroscopic light absorption in these frequency range. The electromagnetic properties of different polished diamonds having several nitrogen concentrations in the frequency range of 100-110 GHz (W band) have been studied. The results indicate that there is a good correlation between the amount of nitrogen impurities and the Free Spectral Range (FSR) parameter of a reflection signal, S11, in the antenna. From the study It is concluded that measuring the diamonds dielectric properties via spectroscopic analysis in the millimeter wavelength range, can determine the color grading. In addition, the FSR measurements were correlated well with the FTIR measurements. The methodology of the new color determination mode and a novel color estimate, based on the FSR vs the nitrogen correlation, has been tested on 26 diamonds with a success rate higher than 70%.
DS1950-0422
1958
Rabkin, M.I.Rabkin, M.I., Solov'yev, D.S.Kimberlites and Diamond Deposits of the Middle Course of The Olenek River.Leningrad: Niiga., Vol. 97.RussiaBlank
DS1960-0085
1960
Rabkin, M.I.Rabkin, M.I., Milashev, V.A.Kimberlite Volcanism of the Northern Part of the Siberian Platform.Niiga., Vol. 114, No. L4.RussiaBlank
DS1960-0162
1961
Rabkin, M.I.Krutoyarskii, M.A., Milashev, V.A., Rabkin, M.I.The Classification of Kimberlitic Rocks of YakutiaNiiga, Info. Bulletin., Vol. 23, PP. 23-26.RussiaBlank
DS1960-0289
1962
Rabkin, M.I.Rabkin, M.I., Krutoyarski, M.A., Milashev, V.A.Classification and Nomenclature of Yakutian KimberlitesNiiga., Vol. 121, PP. 154-164.RussiaBlank
DS1960-0290
1962
Rabkin, M.I.Rabkin, M.I., Milashev, V.A.Volcanic Kimberlites of the North Siberian CratonIn: Symposium On The Geology of The Arctic. International Geol. Re, Vol. 5, No. 7, PP.RussiaBlank
DS1960-0381
1963
Rabkin, M.I.Milashev, V.A., Rabkin, M.I.Kimberlites of the Anabar-olenek Region and Problems of Their Origin.Akad. Nauk Sssr Sib. Div. Yakut., No. 9, PP. 45-53.RussiaBlank
DS1970-0315
1971
Rabkin, M.I.Ilupin, I.P., Rabkin, M.I.Chemical Composition Characteristics of Ilmenite from Kimberlites.Leningrad: Nauch. Issled. Institute Geol. Arktiki, PP. 85-89.Russia, DaldynBlank
DS1970-0391
1971
Rabkin, M.I. EDITOR.Rabkin, M.I. EDITOR.Kimberlitovye Vulkanizm I Perspektivy Korennoi Almazonosnostii Severo- Vostoka Sibirskoi Platformy.Leningrad: N I I G A, 157P.RussiaKimberlite, Kimberley, Janlib
DS1996-0988
1996
Rabonowicz, M.Monnereau, M., Rabonowicz, M.Is the 670 km phase transition able to layer Earth's convection in a mantle with depth dependent viscosity?Geophysical Research Letters, Vol. 23, No. 9, May 1, pp. 1001-1004.MantleStratigraphy, Transition phase
DS200612-0496
2005
Rabonowicz, M.Gregoire, M., Rabonowicz, M., Janse, A.J.A.Mantle mush compaction: a key to understand the mechanisms of concentration of kimberlite melts and initiation of swarms of kimberlite dykes.Journal of Petrology, Vol. 47, 3, March, pp. 631-646,Africa, South Africa, Lesotho, BotswanaConvection, Kimberley, Rietfontein, Central Cape,Gibeon
DS1975-1190
1979
Raby, A.G.Raby, A.G., et al.Geochemical Model for the Origin of Archean Diabase Dikes from the eastern Beartooth Mountains Montana and Wyoming.Guide To The Precambrian Rocks of The Beartooth Mountains, I, P. A14, (abstract.).Montana, WyomingKimberlite, Lherzolite, Rocky Mountains, Geochemistry
DS200812-1027
2008
Racek, M.Schulmann, K., Lexa, O., Stipska, P., Racek, M., Tajcmanova, L., Konpasek, Edel, Peschler, LehmannVertical extension and horizontal channel flow of orogenic lower crust: key exhumation mechanisms in large hot orogens?Journal of Metamorphic Geology, In press availableEurope, MantleGeophysics - bouguer
DS201810-2311
2018
Racek, M.Faryad, S.W., Jedlicka, R., Hauzenberger, C., Racek, M.High pressure crystallization vs. recrystallization origin of garnet pyroxenite-eclogite within subduction related lithologies. Bohemian MassifMineralogy and Petrology, Vol. 112, 5, pp. 603-616.Europe, Austriasubduction

Abstract: Mafic layers displaying transition between clinopyroxenite and eclogite within peridotite from felsic granulite in the Bohemian Massif (Lower Austria) have been investigated. The mafic-ultramafic bodies shared a common granulite facies metamorphism with its hosting felsic rocks, but they still preserve evidence of eclogite facies metamorphism. The selected mafic layer for this study is represented by garnet with omphacite in the core of coarse-grained clinopyroxene, while fine-grained clinopyroxene in the matrix is diopside. In addition, garnet contains inclusions of omphacite, alkali feldspars, hydrous and other phases with halogens and/or CO2. Textural relations along with compositional zoning in garnet from the clinopyroxenite-eclogite layers favour solid-state recrystallization of the precursor minerals in the inclusions and formation of garnet and omphacite during subduction. Textures and major and trace element distribution in garnet indicate two stages of garnet growth that record eclogite facies and subsequent granulite facies overprint. The possible model explaining the textural and compositional changes of minerals is that the granulite facies overprint occurred after formation and exhumation of the eclogite facies rocks.
DS1997-0939
1997
Rachamalla, K.Rachamalla, K.India offers increased mining opportunities for foreign companiesMining Engineering, Vol. 49, No. 2, Feb. pp. 46-47.IndiaMining - laws, Legal
DS1999-0820
1999
Rachibana, T.Yoshimoto, M., Yoshida, K., Rachibana, T.Epitaxial diamond growth on sapphire in an oxidizing environmentNature, Vol. 399, No. 6734, May 27, pp. 340-341.GlobalDiamond - morphology
DS201212-0018
2012
Rachid, F.Araujo, D.P., Silveira, F.V., Weska, R.K., Rachid, F., Neto, F.E.B., Ireland, T., Holden, P., Gobbo, L.Diamonds from the Sao Francisco and Amazon cratons, Brazil.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractSouth America, BrazilDeposit - Andari, Lencois, Barra do Mendes, Catalao, Frutal
DS200612-0591
2006
Rachid Houari, M.Hoepffner, C., Rachid Houari, M., Bouabdelli, M.Tectonics of the North African Variscides ( Morocco, western Algeria) - an outline.Comptes Rendus Geoscience, Vol. 338, 1-2, pp. 25-Africa, MoroccoTectonics
DS1989-1310
1989
Rachkov, V.S.Rozen, O.M., Nozhkin, A.D., Zlobin, V.L., Rachkov, V.S.Distribution of radioactive elements in the metamorphic rocks of the Anabar shield: origin of the rocks and evolution of the crustInternational Geology Review, Vol. 31, No. 8, August pp. 780-791RussiaAnabar shield, metamorphism
DS1997-0940
1997
Rachmalla, K.Rachmalla, K.India offers increased mining opportunities for foreign companiesMining Engineering, Vol. 49, No. 2, Feb. pp. 46-47IndiaMining, Legal
DS1997-0741
1997
Rachmalla, K.S.Mason, J.D., Rachmalla, K.S.Exploration financing - innovative approach lowers risk17th. World Mining Congress Oct. Mexico, pp. 459-470CanadaEconomics, discoveries, Risk Financing
DS1995-1537
1995
Rada, R.Rada, R.Interactive mediaSpringer Verlag, 256pGlobalInteractive media, Book -ad
DS1989-1542
1989
Radbruch-Hall, D.H.Varnes, D.J., Radbruch-Hall, D.H., Savage, W.Z.Topographic and structural conditions in areas of gravitational spreading of ridges in the western United StatesUnited States Geological Survey (USGS) Prof. Paper, No. 1496, 28pColorado, MontanaStructure, General-specific regions
DS2002-1296
2002
Raddick, M.J.Raddick, M.J., Parmentier, E.M., Scheirer, D.S.Buoyant decompression melting: a possible mechanism for intraplate volcanismJournal of Geophysical Research, Oct. 29, 10.1029/2001JB000617.MantleMelting, Magmatism
DS200812-0465
2008
Rademan, J.Herbst, J., Potapov, A., Hambidge, G., Rademan, J.Modeling of diamond liberation and damage for Debswana kimberlitic ores.Minerals Engineering, Vol. 21, 11, October pp. 766-789.Africa, BotswanaMining - mineral processing
DS201901-0037
2018
Radeneyer, M.Grantham, G., Eglinton, B., Macey, P.H., Ingram,B., Radeneyer, M., Kaiden, H., Manhica, V.The chemistry of Karoo age andesitic lavas along the northern Mozambique coast, southern Africa and possible implications for Gondwana breakup.South African Journal of Geology, Vol. 121, pp. 271-286.Africa, Mozambiquegeodynamics

Abstract: Major, trace, radiogenic isotope and stable isotope data from lavas along the northeastern coast of Mozambique are described. The whole rock composition data demonstrate that the rocks are dominantly andesitic with compositions typical of calc-alkaline volcanic rocks from arc environments. SHRIMP U/Pb data from zircons indicate that the zircons are xenocrystic, having ages of between 500 Ma and 660 Ma, with the age of the lava constrained by Rb/Sr data at ~184 Ma. Strontium, Nd and Pb radiogenic isotope data support an interpretation of extensive mixing between a Karoo age basaltic magma (dolerite) from Antarctica and continental crust similar in composition to the Mozambique basement. Oxygen isotope data also imply a significant crustal contribution to the lavas. Possible tectonic settings for the lavas are at the margin of a plume or from a locally restricted compressional setting during Gondwana breakup processes.
DS1990-1208
1990
Radetzki, M.Radetzki, M.Economic development and the timing of mineral exploitation: a critical review of some conventional wisdomsColorado School of Mines, Department of Mineral Economics, Working Paper, No. 89-8, February 13pGlobalEconomics, Mineral exploitation -timing
DS1994-1423
1994
Radetzki, M.Radetzki, M.Mineral exploitation - regional development in a historical perspectiveRaw Materials Report, Vol. 10, No. 1, pp. 2-7GlobalEconomics, Mineral resource development
DS1994-1424
1994
Radhakri, B.P.Radhakri, B.P.New thinking on diamond explorationJournal of Geological Society India, Vol. 44, No. 4, October p. 366.IndiaDiamond exploration
DS1996-1152
1996
Radhakri, S.P.Radhakri, S.P.Diamond formation in uranium rich carbonaceous matterJournal of Geological Society India, Vol. 48, No. 5, Nov. p. 592.IndiaDiamond genesis, UraniuM.
DS200612-1120
2006
Radhakrishna, B.P.Radhakrishna, B.P.Some thoughts on diamond exploration in India.Journal of the Geological Society of India, Vol. 67, pp. 283-288.IndiaDiamond exploration - brief overview
DS1994-1425
1994
Radhakrishna, T.Radhakrishna, T., Dallmeyer, R.D., Joseph, M.Paleomagnetism and 36 Ar-40 Ar vs 39 Ar-40 Ar isotope correlation ages of dyke swarms in central Kerala, India: tectonic implications.Earth and Planetary Science Letters, Vol. 121, No. 1/2, January pp. 213-226.IndiaDikes, isotope correlation, Argon, Tectonics
DS1994-1426
1994
Radhakrishna, T.Radhakrishna, T., Dallmeyer, R.D., Joseph, M.Paleomagnetism and 36 Ar-40Ar vs 39Ar-40r isotope correlation ages of dyke swarms in central Kerala, India: tectonic implications.Earth and Planetary Science Letters, Vol. 121, pp. 213-226.IndiaPaleomagnetics, Argon, Dykes
DS1996-1153
1996
Radhakrishna, T.Radhakrishna, T., et al.Proterozoic paleomagnetism of the mafic dyke swarms in the high grade region of southern India.Precambrian Research, Vol. 76, No. 1, 2, Jan. 1, pp. 31-46.IndiaDyke swarms, Geophysics -Paleomagnetism
DS1998-1201
1998
Radhakrishna, T.Radhakrishna, T., Joseph, M.Geochemistry and petrogenesis of the Proterozoic dikes in Tamil Nadu:another example of Archean lithosphericGeol. Rundsch., Vol. 87, No. 3, Dec. pp. 268-82.India, southern IndiaDike - mantle source
DS2003-1122
2003
Radhakrishna, T.Radhakrishna, T., Joseph, M., Krishnendu, N.R., Balasubramonian, G.Paleomagnetism of mafic dykes in Dharwar Craton: possible geodynamic implicationsGeological Society of India Memoir, No. 50, pp. 193-224.IndiaGeophysics - magnetics
DS200412-1608
2003
Radhakrishna, T.Radhakrishna, T., Joseph, M., Krishnendu, N.R., Balasubramonian, G.Paleomagnetism of mafic dykes in Dharwar Craton: possible geodynamic implications.Geological Society of India Memoir, No. 50, pp. 193-224.IndiaGeophysics - magnetics
DS201312-0726
2013
Radhakrishna, T.Radhakrishna, T., Chandra, R., Srivastava, A.K., Balasubramonian, G.Central/eastern Indian Bundelk hand and Bastar cratons in the Paleoproterozoic supercontinental reconstructions: a paleomagnetic perspective.Precambrian Research, Vol. 226, pp. 91-104.IndiaPaleomagnetism
DS201312-0727
2013
Radhakrishna, T.Radhakrishna, T., Krishnendu, N.R., Balasubramonian, G.Nd-Hf isotope systematics of megacrysts from the Mbuji-Mayi kimberlites, D.R. Congo: evidence for a metasomatic origin related to kimberlite interaction with the cratonic lithosphere mantle.Earth Science Reviews, in press availableIndiaGondwana
DS201312-0728
2013
Radhakrishna, T.Radhakrishna, T., Krishnendu, N.R., Balasubramonian, G.Paleoproterozoic Indian shield in the global continental assembly: evidence from the paleomagnetism of mafic dyke swarms.Earth Science Reviews, Vol. 126, pp. 370-389.IndiaDykes
DS201709-2045
2017
Radhakrishna, T.Radhakrishna, T., Soumya, G.S., Satyanarayana, K.V.V.Paleomagnetism of the Cretaceous lamproites from Gondwana basin of the Damodar Valley in India and migration of the Kerguelen plume in the southeast Indian Ocean.Journal of Geodynamics, Vol. 109, pp. 1-9.Indialamproites

Abstract: The paper presents new palaeomagnetic results and reassesses complete set of published palaeomagnetic results on the lamproite intrusions in the Gondwana formations of the Eastern India. Altogether eleven sites register reliable characteristic magnetisations corresponding to the c. 110 Ma emplacement age of the lamproites. A mean ChRM is estimated with D = 331.3°; I = -62.4° (a95 = 6.2°, k = 55; N = 11). The palaeomagnetic pole of ? = 14.9°: F = 287.6° (A95 = 8.4°) is established for the lamproites and it averaged the secular variation and confirms to the Geocentric Axial Dipole (GAD). The pole compares remarkably well with the grand mean pole reported for the Rajmahal traps that are attributed to represent location of the Kerguelen mantle plume head. The palaeolatitudes transferred to Rajmahal coordinates (25.05°: 87.84°) are situated ~6° north of the present location of the Kerguelen hotspot location. The interpretations are consistent with earlier suggestions of southward migration of the plume based on palaeomagnetic results of Site 1138 of the ODP Leg 183 and with the predictions of numerical models of global mantle circulation.
DS1990-1209
1990
Radhakrishna Murthy, I.V.Radhakrishna Murthy, I.V., Krishnamacharyulu, S.K.G.Automatic inversion of gravity anomalies of faultsComputers and Geosciences, Vol. 16, No. 4, pp. 539-548GlobalComputer, Program -faults/gravity
DS1988-0560
1988
Radhakrishnamurty, C.Radhakrishnamurty, C., Likhite, S.D., Murthy, G.S.Magnetic studies on the remanence carriers in Igneous rocks of differentagesProceedings of the Indian Academy of Sciences, Vol. 97, No. 1, July pp. 81-86IndiaGeophysics
DS1997-0941
1997
Radhakrishnan, V.Radhakrishnan, V., Mariappan, N., Thrivikramji, L.P.A QUICKBASE program to analyse pebble shapesComputers and Geosciences, Vol. 23, No. 3, pp. 325-327.GlobalZingg shape classification, Alluvials, placers, pebbles
DS2002-0284
2002
RadigonCheng, L.Z., Mareschal, J.C., Jaupart, C., Rolandone, F., Gariepy, C., RadigonSimultaneous inversion of gravity and heat flow data: constraints on thermal regimeJournal of Geodynamics, Vol. 34, 1, pp. 11-30.Ontario, ManitobaGeothermometry, Lithosphere - Abitibi subprovince, Thompson Belt
DS200612-0384
2006
Radina, E.S.Evdokimov, A.N., Burnaeva, M.Yu., Radina, E.S., Sirotkin, A.N.The first find of kimberlitic accessory minerals in mafic-ultramafic dikes in Spitsbergen.Doklady Earth Sciences, Vol. 407, 2, Feb-Mar. pp. 275-279.Europe, NorwayGeochemistry
DS1985-0552
1985
Radionov, A.S.Radionov, A.S., Sobolev, N.V.A New Find of Graphite Containing Harzburgite Xenoliths Inkimberlite.(russian)Geol. Geofiz., (Russian), No. 12, pp. 32-37RussiaHarzburgite
DS1970-0566
1972
Radionov, M.N.Molochnov, G.V., Radionov, M.N., Genin, B.L.Use of Dipole Electric-magnetic Sounding in Determining The thickness of Alluvium During Exploration for Beach Diamond Placers in the Region of Anabar Bay.Geofiz. Metody Razved. Arkt., No. 7, PP. 68-73.Russia, YakutiaKimberlite, Geophysics
DS1991-1393
1991
Radko, V.A.Radko, V.A.Model of dynamic differentiation of intrusive traps in the northwestern Siberian PlatformSoviet Geology and Geophysics, Vol. 32, No. 11, pp. 15-20RussiaLayered intrusions, platinum group elements (PGE), Nickel
DS202009-1634
2020
Radomskaya, T.A.Kaneva, E., Shendrik, R.Yu., Radomskaya, T.A., Suvorova, L.E.Fedorite from Murun alkaline complex ( Russia): spectroscopy and crystal chemical features.Minerals ( MDPI), Vol. 10, 702, 24p. PdfRussiadeposit - Murun

Abstract: Fedorite is a rare phyllosilicate, having a crystal structure characterized by SiO4-tetrahedral double layers located between continuous layers formed by edge-sharing (Ca,Na)-octahedra, and containing interlayer K, Na atoms and H2O molecules. A mineralogical-petrographic and detailed crystal-chemical study of fedorite specimens from three districts of the Murun alkaline complex was performed. The sequence of the crystallization of minerals in association with fedorite was established. The studied fedorite samples differ in the content of interlayer potassium and water molecules. A comparative analysis based on polyhedral characteristics and deformation parameters was carried out. For the first time, EPR, optical absorption and emission spectra were obtained for fedorite. The raspberry-red coloration of the mineral specimens could be attributed to the presence of Mn4+ ions.
DS202010-1847
2020
Radomskaya, T.A.Kaneva, E.V., Shendrik, R.Yu., Radomskaya, T.A., Suvorova, L.F.Fedorite from Murun alkaline complex ( Russia): spectroscopy and crystal chemical features.Minerals, Vol. 10, 702 10.3390/min10080702 24p. PdfRussia, Yakutiadeposit - Murun

Abstract: Fedorite is a rare phyllosilicate, having a crystal structure characterized by SiO4-tetrahedral double layers located between continuous layers formed by edge-sharing (Ca,Na)-octahedra, and containing interlayer K, Na atoms and H2O molecules. A mineralogical-petrographic and detailed crystal-chemical study of fedorite specimens from three districts of the Murun alkaline complex was performed. The sequence of the crystallization of minerals in association with fedorite was established. The studied fedorite samples differ in the content of interlayer potassium and water molecules. A comparative analysis based on polyhedral characteristics and deformation parameters was carried out. For the first time, EPR, optical absorption and emission spectra were obtained for fedorite. The raspberry-red coloration of the mineral specimens could be attributed to the presence of Mn4+ ions.
DS202107-1112
2021
Radomskaya, T.A.Marfin, A., Radomskaya, T.A., Ivanov, A.V., Belozerova, O.Y.U-Pb dating of apatite, titanite and zircon of the Kingash mafic-ultramafic massif, Kan terrane Siberia: from Rodinia break-up to the reunion of the Siberian craton.Journal of Petrology, Vol. 62, 6, EGAb049Russia, Siberiacratons

Abstract: The initial stage of Rodinia supercontinent break-up occurred at about 750?Ma. It preceded formation of the Irkutsk and Franklin Large Igneous Provinces (LIPs)at 712 ± 2?Ma to 739 ± 8?Ma. These LIPs were emplaced within the formerly connected Laurentian and Siberian cratons. The Kingash massif is located in the Precambrian Kan terrane in direct contact with the Siberian Craton at its southwestern boundary. It has been linked to an important suite of mafic-ultramafic intrusions which border the southern margin of the Siberian craton, and which have been inferred to belong to the Irkutsk LIP. The massif is also significant, because it hosts PGE-Cu-Ni rich mineralization and is the only large deposit in the region. However, despite numerous dating attempts, the age of the massif had not been resolved. A significant difficulty is post-magmatic recrystallization at amphibolite facies that affected the rocks of the massif. In this study we used U-Pb dating of zircon, titanite and apatite from rocks of the Kingash massif and cross-cutting granite and monzonite veins. The oldest igneous zircon grain of the Kingash massif analysed by LA-ICPMS yields an age of c. 750?Ma, taken as a tentative age of magmatism. Dating of multiple grains of metamorphic zircon by CA-ID-TIMS yielded 564.8 ± 2.2?Ma, which is in agreement with LA-ICPMS titanite ages 557 ± 19?Ma, 565 ± 35?Ma and 551 ± 17?Ma. Apatite of two different samples showed ages of 496.4 ± 7.9?Ma and 497.0 ± 1.8?Ma (LA-ICPMS), which are interpreted as the time when the terrane cooled below the closure temperature of apatite. Using our new data we suggest that at the time of the Irkutsk-Franklin LIP event the Kan terrane was a part of Rodinia, then it separated from either Siberia or Laurentia during the break-up of Rodinia and finally collided with Siberia at 560?Ma; the time of regional amphibole facies metamorphism.
DS201709-2046
2017
Radu, I.B.Radu, I.B., Harris, C., Moine, B., Costin, G., Cottin, J-Y.Subduction relics in the cratonic root - evidence from delta O18O variations in eclogite xenoliths.Goldschmidt Conference, abstract 1p.Africa, South Africadeposit, Roberts Victor, Jagersfontein
DS202009-1641
2020
Radu, I.B.Moine, B.N., Bolfan-Casanova, N., Radu, I.B., Ionov, D.A., Costin, G., Korsakov, A.V., Golovin, A.V., Oleinikov, O.B., Deloule, E., Cottin, J.Y.Molecular hydrogen in minerals as a clue to interpret deltaD variations in the mantle. ( Omphacites from eclogites from Kaapvaal and Siberian cratons.)Nature Communications, doi:.org/10.1038/ s41467-020-17442 -8 11p. PdfAfrica, South Africa, Russia, Siberiawater

Abstract: Trace amounts of water dissolved in minerals affect density, viscosity and melting behaviour of the Earth’s mantle and play an important role in global tectonics, magmatism and volatile cycle. Water concentrations and the ratios of hydrogen isotopes in the mantle give insight into these processes, as well as into the origin of terrestrial water. Here we show the presence of molecular H2 in minerals (omphacites) from eclogites from the Kaapvaal and Siberian cratons. These omphacites contain both high amounts of H2 (70 to 460 wt. ppm) and OH. Furthermore, their ?D values increase with dehydration, suggesting a positive H isotope fractionation factor between minerals and H2-bearing fluid, contrary to what is expected in case of isotopic exchange between minerals and H2O-fluids. The possibility of incorporation of large quantities of H as H2 in nominally anhydrous minerals implies that the storage capacity of H in the mantle may have been underestimated, and sheds new light on H isotope variations in mantle magmas and minerals.
DS201607-1373
2016
Radu, I-B.Radu, I-B.Kyanite bearing eclogite xenoliths from the Udachanaya kimberlites, Siberia.IGC 35th., Session A Dynamic Earth 1p. AbstractRussiaKimberlite
DS201710-2259
2017
Radu, I-B.Radu, I-B., Moine, B., Ionov, D., Korsakov, A., Golovin, A., Mikhailenko, D., Cottin, J-Y.Kyanite-bearing eclogite xenoliths from the Udachnaya kimberlite, Siberian craton, Russia.Bulletin de la Societe Geologique de France *eng, Vol. 188, 1-2, 14p.Russia, Siberiadeposit - Udachnaya

Abstract: Xenoliths brought up by kimberlite magmas are rare samples of otherwise inaccessible lithospheric mantle. Eclogite xenoliths are found in most cratons and commonly show a range of mineral and chemical compositions that can be used to better understand craton formation. This study focuses on five new kyanite-bearing eclogites from the Udachnaya kimberlite pipe (367±5 Ma). They are fine-to coarse-grained and consist mainly of “cloudy” clinopyroxene (cpx) and garnet (grt). The clinopyroxene is Al,Na-rich omphacite while the garnet is Ca-rich, by contrast to typical bi-mineral (cpx+grt) eclogites that contain Fe- and Mg-rich garnets. The Udachnaya kyanite eclogites are similar in modal and major element composition to those from other cratons (Dharwar, Kaapvaal, Slave, West African). The kyanite eclogites have lower REE concentrations than bi-mineral eclogites and typically contain omphacites with positive Eu and Sr anomalies, i.e. a “ghost plagioclase signature”. Because such a signature can only be preserved in non-metasomatised samples, we infer that they were present in the protoliths of the eclogites. It follows that subducted oceanic crust is present at the base of the Siberian craton. Similar compositions and textures are also seen in kyanite eclogites from other cratons, which we view as evidence for an Archean, subduction-like formation mechanism related to craton accretion. Thus, contrary to previous work that classifies all kyanite eclogites as type I (IK), metasomatized by carbonatite/kimberlitic fluids, we argue that some of them, both from this work and those from other cratons, belong to the non-metasomatized type II (IIB). The pristine type IIB is the nearest in composition to protoliths of mantle eclogites because it contains no metasomatic enrichments.
DS1996-1082
1996
Radwanek-Bak, B.Paulo, A., Radwanek-Bak, B.The mineral industry of the Ukraine - a reviewErzmetall, Vol. 49, No. 1, Jan. pp. 61-69UKraineMineral industry, Review
DS200712-0964
2007
Radziminovich, Y.A.Seminskii, K., Radziminovich, Y.A.Seismicity of the southern Siberian platform: spatiotemporal characteristics and genesis.Izvestia, Physics of the Solid Earth, Vol. 43, 9, Sept., pp. 726-737. IngentaRussiaGeophysics - seismics
DS200812-1083
2008
Radziminovich, Ya.B.Smininsky, K.Zh., Gladkov, A.S., Radziminovich, Ya.B., Cheremnykh, A.V., Bobrov, A.A.Regularities of manifestation of active faults and seismicity in the southern part of the Siberian craton.Doklady Earth Sciences, Vol. 422, 1, October pp. 1068-1972.Russia, SiberiaGeophysics - seismics
DS1993-0790
1993
Raeburn, S.P.Kasting, J.F., Eggler, D.H., Raeburn, S.P.Mantle redox evolution and the oxidation state of the Archean atmosphereJournal of Petrology, Vol. 101, No. 2, March pp. 245-258MantleXenoliths, Geochemistry
DS201905-1069
2019
Raeisi, D.Raeisi, D., Gholoizade, K., Nayebi, N., Babazadeh, S., Nejadhadad, M.Geochemistry and mineral composition of lamprophyre dikes, central Iran: implications for petrogenesis and mantle evolution.Journal of Earth System Science, Vol. 128:74Europe, Iranlamprophyre

Abstract: Late Proterozoic-Early Cambrian magmatic rocks that range in composition from mafic to felsic have intruded into the Hour region of the central Iranian micro-continent. The Hour lamprophyres are alkaline, being characterized by low contents of SiO2 and high TiO2, Mg# values, high contents of compatible elements, and are enriched in LREE and LILE but depleted in HFSE. Mineral chemistry studies reveal that the lamprophyres formed within a temperature range of ~1200° to 1300°C and relatively moderate pressure in subvolcanic levels. The Hour lamprophyres have experienced weak fractional crystallization and insignificant crustal contamination with more primitive mantle signatures. They were derived from low degree partial melting (1-5%) of the enriched mantle characterized by phlogopite/amphibole bearing lherzolite in the spinel-garnet transition zone at 75-85 km depth, and with an addition of the asthenospheric mantle materials. We infer the Hour lamprophyres to be part of the alkaline rock spectrum of the Tabas block and their emplacement, together with that of other alkaline complexes in the central Iran, was strongly controlled by pre-existing crustal weakness followed by the asthenosphere-lithospheric mantle interaction during the Early Cambrian.
DS201412-0640
2014
Raepsaet, C.Novella, D., Frost, D.J., Hauri, E.H., Bureau, H., Raepsaet, C., Roberge, M.The distribution of H2O between silicate melt and nominally anhydrous peridotite and the onset of hydrous melting in the deep upper mantle.Earth and Planetary Science Letters, Vol. 400, pp. 1-13.MantleMelting
DS201706-1101
2017
Raepsaet, C.Roberge, M., Bureau, H., Bolfan-Casanova, N., Raepsaet, C., Surble, S., Khodja, H., Auzende, A-L., Cordier, P., Fiquet, G.Chlorine in wadsleyite and ringwoodite: an experimental study.Earth and Planetary Science Letters, Vol. 467, pp. 99-107.Mantlechlorine

Abstract: We report concentrations of Chlorine (Cl) in synthetic wadsleyite (Wd) and ringwoodite (Rw) in the system NaCl-(Mg,?Fe)2SiO4 under hydrous and anhydrous conditions. Multi-anvil press experiments were performed under pressures (14-22 GPa) and temperatures (1100-1400?°C) relevant to the transition zone (TZ: 410-670 km depth). Cl and H contents were measured using Particle Induced X-ray Emission (PIXE) and Elastic Recoil Detection Analysis (ERDA) respectively. Results show that Cl content in Rw and Wd is significantly higher than in other nominally anhydrous minerals from the upper mantle (olivine, pyroxene, garnet), with up to 490 ppm Cl in anhydrous Rw, and from 174 to 200 ppm Cl in hydrous Wd and up to 113 ppm Cl in hydrous Rw. These results put constrains on the Cl budget of the deep Earth. Based on these results, we propose that the TZ may be a major repository for major halogen elements in the mantle, where Cl may be concentrated together with H2OH2O and F (see Roberge et al., 2015). Assuming a continuous supply by subduction and a water-rich TZ, we use the concentrations measured in Wd (174 ppm Cl) and in Rw (106 ppm Cl) and we obtain a maximum value for the Cl budget for the bulk silicate Earth (BSE) of 15.1 × 1022 g Cl, equivalent to 37 ppm Cl. This value is larger than the 17 ppm Cl proposed previously by McDonough and Sun (1995) and evidences that the Cl content of the mantle may be higher than previously thought. Comparison of the present results with the budget calculated for F (Roberge et al., 2015) shows that while both elements abundances are probably underestimated for the bulk silicate Earth, their relative abundances are preserved. The BSE is too rich in F with respect to heavy halogen elements to be compatible with a primordial origin from chondrites CI-like (carbonaceous chondrites CC) material only. We thus propose a combination of two processes to explain these relative abundances: a primordial contribution of different chondritic-like materials, including EC-like (enstatite chondrites), possibly followed by a distinct fractionation of F during the Earth differentiation due to its lithophile behavior compared to Cl, Br and I.
DS201904-0757
2019
Raepsaet, C.Malavergegne, V., Bureau, H., Raepsaet, C., Gaillard, C., Poncet, F., Surble, M., Sifre, S., Shcheka, D., Fourdrin, S., Deldicque, C., Khodja, D., HichamExperimental constraints on the fate of H and C during planetary core-mantle differentiation. Implications for the Earth.Icarus - New York, Vol. 321, 1, pp. 473-485.Mantlecarbon

Abstract: Hydrogen (H) and carbon (C) have probably been delivered to the Earth mainly during accretion processes at High Temperature (HT) and High Pressure (HP) and at variable redox conditions. We performed HP (1-15?GPa) and HT (1600-2300°C) experiments, combined with state-of-the-art analytical techniques to better understand the behavior of H and C during planetary differentiation processes. We show that increasing pressure makes H slightly siderophile and slightly decreases the highly siderophile nature of C. This implies that the capacity of a growing core to retain significant amounts of H or C is mainly controlled by the size of the planet: small planetary bodies may retain C in their cores while H may have rather been lost in space; larger bodies may store both H and C in their cores. During the Earth's differentiation, both C and H might be sequestrated in the core. However, the H content of the core would remain one or two orders of magnitude lower than that of C since the (H/C)core ratio might range between 0.04 and 0.27.
DS201910-2246
2019
Raepsat, V.Bureau, H., Raepsat, V., Esteve, I., Armstrong, K., Manthilake, G.Replicate mantle diamonds.Goldschmidt2019, 1p. AbstractMantlediamond genesis

Abstract: Still today, diamond growth in the mantle is difficult to understand. It may implicate different processes but there is an agreement to involve fluids as diamonds parents. The composition of these fluids is supposed to be variable depending of the the settings and depths. Natural diamonds also exhibit dissolution features, possibly mantle-derived and not only due to kimberlite-induced resorption during magma ascent [1]. We present experimental results devoted to understand diamond growth versus dissolution mechanisms in the lithosphere. Experiments are performed using multianvil presses at 7 GPa, 1300-1675°C for a few hours (4 to 27 hrs). As starting materials we use mixtures of water, carbonates, natural lherzolite or MORB, graphite and diamonds seeds resulting in hydrous-carbonate-silicate fluids at high pressure and temperature. For similar pressure and temperature conditions, results show that diamonds are formed or dissolved in these fluids, depending on the redox conditions. Focussed ion beam preparations of the diamonds evidence that when they grow, they trap multi-phased inclusions similar to those observed in fibrous, coated and monocrystalline natural diamonds, in agreement with previous studies [2-4].
DS1975-0842
1978
Raeside, R.P.Raeside, R.P.A Reinvestigation of the Ile Bizard Kimberlite MontrealEos, Vol. 59, No. 4, P. 393. (abstract.).Canada, QuebecAlnoite
DS1975-0843
1978
Raeside, R.P.Raeside, R.P.A Reinvestigation of the Ile Bizard Kimberlite and its Ultramafic Xenolith Suite, Montreal.Kingston: Msc. Thesis, Queen's University, Canada, QuebecKimberlite, Alnoite
DS1982-0513
1982
Raeside, R.P.Raeside, R.P., Helmstaedt, H.The Ile Bizard Intrusion, Montreal, Quebec- Kimberlite or Lamprophyre?Canadian Journal of Earth Sciences, Vol. 19, No. 10, PP. 1996-2011.Canada, QuebecKimberlite, Xenolith, Breccia, Diatreme, Alnoite
DS1983-0528
1983
Raeside, R.P.Raeside, R.P., Helmstaedt, H.The Ile Bizard Intrusion, Montreal, Quebec- Kimberlite or Lamprophyre? Discussion.Canadian Journal of Earth Sciences, Vol. 20, No. 9, PP. 1496-1498.Canada, QuebecGenesis, Kimberlite, Alnoite
DS200812-0414
2008
Raevskii, A.B.Glaznev, V.N., Zhirova, A.M., Raevskii, A.B.New dat a on the deep structure of the Khibiny and Lovozero massifs, Kola Peninsula.Doklady Earth Sciences, Vol. 422, 1 Oct. pp. 391-393.Russia, Kola PeninsulaGeophysics
DS1996-0047
1996
Raevsky, A.Arzamastesev, A., Glaznev, V., Raevsky, A.Deep structure of Precambrian basement in the area of the Kola alkalineprovince: geophysics and petrogenesisInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 1, p. 111.Russia, Kola PeninsulaGeophysics, Tectonics
DS2000-0026
2000
Raevsky, A.B.Arazamastev, A.A., Glaznev, V.N., Raevsky, A.B., et al.Morphology and internal structure of the Kola alkaline province, northeast Fennoscandian Shield: 3D density modelingJournal of Asian Earth Science, Vol. 18, No.2, Apr. pp.213-28.Russia, Kola, FennoscandiaGeophysics - density, structure, tectonics, Kola alkaline province
DS2001-0957
2001
Raffan, N.Raffan, N.Buy side investment approach to the valuation of mining shares: a fund manager's viewValmin 01, Mineral Asset Valuation Oct. 25-6th., pp.195-200.AustraliaEconomics - cash flows, Mineral reserves, resources, valuation, exploration
DS201704-0627
2017
Raffle, K.Greig, J., Besserer, D., Raffle, K.Exploring forgotten diamond-bearing ground in the North Slave Craton. Muskox and JerichoVancouver Kimberlite Cluster, Apr. 5, 1p. AbstractCanada, NunavutDeposit - Jericho
DS200912-0607
2009
Raffone, N.Raffone, N., Chazot, G., Pin, C., Vannucci, R., Zanetti, A.Metasomatism in the lithospheric mantle beneath Middle Atlas ( Morocco) and the origin of Fe- and Mg- rich wehrlites.Journal of Petrology, Vol. 50, 2, pp. 197-249.Africa, MoroccoMetasomatism
DS1989-0522
1989
Ragan, V.M.Goebel, E.D., Coveney, R.M.Jr., Ragan, V.M.Sulfur isotopes and fluid inclusions from trace and minor occurrences of Mississippi Valley type base metals in country rocks in the mid-continentGeological Society of America (GSA) Abstract Volume, Vol. 21, No. 4, p. 12. (abstract.)Missouri, MidcontinentGeochronology
DS200412-1423
2004
Ragel Da Silva, J.M.Neves, S.P., Melo, S.C., Moura, C.A.V., Mariano, G., Ragel Da Silva, J.M.Zircon Pb Pb geochronology of the Aruaru area, northeastern Brazil: temporal constraints on the Proterozoic evolution of BorboreInternational Geology Review, Vol. 46, 1, pp. 52-63.South America, BrazilGeochronology
DS1989-1249
1989
Raghavan, V.Raghavan, V., Panchanathan, P.V.Fortran 77 utilities for lineament dat a analysisCogs Computer Contributions, Vol. 5, No. 1, pp. 1-15. Database # 18161GlobalComputer, Program - utilities Fortran 77
DS1993-1275
1993
Raghaven, V.Raghaven, V., Wadatsumi, K., Masumoto, S.Automatic extraction of lineament information from satellite images using digital eleveation dataNonrenewable Resources, Vol. 2, No. 2, Summer pp. 148-155JapanRemote sensing, Tectonics, structure
DS1994-1427
1994
Raghaven, V.Raghaven, V., et al.SMILES: a Fortran 77 program for sequential machine interpreted lineament extraction using digital imagesComputers and Geosciences, Vol. 20, No. 2, pp. 121-159GlobalComputer Program, Program -SMILES
DS200612-0484
2006
Raghubabu, K.Goutham, M.R., Raghubabu, K., Prasad, C.V.R.K., Subbarao, K.V., Reddy, V.D.A Neoproterozoic geomagnetic field reversal from the Kurnool Group, India: implications for stratigraphic correlation and formation of Gondwana.Journal of the Geological Society of India, Vol. 67, 2, pp. 221-233.Asia, IndiaGeophysics - magnetics, paleomagnetism
DS2002-0272
2002
Raghuram, H.M.Chakravarthi, V., Raghuram, H.M., Singh, S.B.3 D forward gravity modeling of basement interfaces above which density contrast varies continuously depthComputers and Geosciences, Vol.28, 2, Feb.pp. 53-7.GlobalComputers, Gravity
DS201904-0769
2019
Raghuvanshi, S.Raghuvanshi, S., Pandey, A., Pankaj, P., Chalapathi Rao, N.V., Chakrabarti, R., Pandit, D., Pandey, R.Lithosphere - asthenosphere interaction and carbonatite metasomatism in the genesis of Mesoproterozoic shoshonitic lamprophryres at Krakkodu, Wajrakarur kimberlite field, eastern Dharwar Craton, southern India.Geological Journal, doi: 10.1002/gj.3468 18p.Indiadeposit - Wajrakarur

Abstract: The spatial and temporal association between lamprophyres and kimberlites provides unique opportunities to explore their genetic relationships. This paper explores such a relationship by detailing mineralogical and geochemical aspects of Korakkodu lamprophyre dykes located within the well-known Mesoproterozoic diamondiferous Wajrakarur Kimberlite field (WKF), towards the south-western margin of Paleo-Mesoproterozoic Cuddapah Basin, Eastern Dharwar Craton, southern India. Mineralogy reveals that these dykes belong to calc-alkaline variety of lamprophyres, but their geochemistry display mixed signals of both alkaline and calc-alkaline lamprophyres. These lamprophyres are highly potassic, and their high Al2O3 and low-TiO2 content implies a shoshonitic character. Low Mg#, Ni, and Cr concentration highlight their evolved nature. High (La/Yb)N and (Gd/Yb)N content is consistent with their derivation from low degrees of partial melting, whereas highly fractionated nature suggests the presence of garnet in their source. Absence of prominent Nb-Ta anomaly implies to the dilution of lithospheric mantle source by melts rich in HFSEs and low La/Nb ratio compared to those of the calc-alkaline island arc volcanics and suggests an asthenospheric overprint on lithospheric mantle source. Carbonatite metasomatism in the source region of these lamprophyres is apparent from conspicuously high-Zr/Hf ratio, and the HFSE budget of these lamprophyres are principally controlled by the presence of phlogopite veins in their lithospheric source. An extremely heterogeneous and layered lithospheric mantle beneath Eastern Dharwar Craton has been inferred from the divergent genetic history of Mesoproterozoic lamprophyres and kimberlites in the Wajrakarur field.
DS201910-2293
2019
Raghuvanshi, S.Raghuvanshi, S., Pandey, A., Pankaj, P., Chalapathi Rao, N.V., Chakrabati, R., Pandit, D., Pandey, R.Lithosphere-asthenosphere interaction and carbonatite metasomatism in the genesis of Mesoproterozoic shoshonitic lamprophyres at Korakkodu, Wajrakarur kimberlite field, eastern Dharwar craton, southern India.Geological Journal, Vol. 54, 5, pp. 3060-3077.Indiadeposit - Wajrakarur

Abstract: The spatial and temporal association between lamprophyres and kimberlites provides unique opportunities to explore their genetic relationships. This paper explores such a relationship by detailing mineralogical and geochemical aspects of Korakkodu lamprophyre dykes located within the well-known Mesoproterozoic diamondiferous Wajrakarur Kimberlite field (WKF), towards the south-western margin of Paleo-Mesoproterozoic Cuddapah Basin, Eastern Dharwar Craton, southern India. Mineralogy reveals that these dykes belong to calc-alkaline variety of lamprophyres, but their geochemistry display mixed signals of both alkaline and calc-alkaline lamprophyres. These lamprophyres are highly potassic, and their high Al2O3 and low-TiO2 content implies a shoshonitic character. Low Mg#, Ni, and Cr concentration highlight their evolved nature. High (La/Yb)N and (Gd/Yb)N content is consistent with their derivation from low degrees of partial melting, whereas highly fractionated nature suggests the presence of garnet in their source. Absence of prominent Nb-Ta anomaly implies to the dilution of lithospheric mantle source by melts rich in HFSEs and low La/Nb ratio compared to those of the calc-alkaline island arc volcanics and suggests an asthenospheric overprint on lithospheric mantle source. Carbonatite metasomatism in the source region of these lamprophyres is apparent from conspicuously high-Zr/Hf ratio, and the HFSE budget of these lamprophyres are principally controlled by the presence of phlogopite veins in their lithospheric source. An extremely heterogeneous and layered lithospheric mantle beneath Eastern Dharwar Craton has been inferred from the divergent genetic history of Mesoproterozoic lamprophyres and kimberlites in the Wajrakarur field.
DS202008-1431
2020
Raghuvanshi, S.Pankaj, P., Giri, R.K., Chalapathi Rao, N.V., Charabarti, R., Raghuvanshi, S.Mineralogy and petrology of shoshonitic lamprophyre dykes from the Sivarampeta area, diamondiferous Wajrakarur kimberlite field, eastern Dharwar craton, southern India.Journal of Mineralogical and petrological Sciences, Vol. 115, 2, pp. 202-215. pdfIndiadeposit - Wajrakarur

Abstract: Petrology and geochemistry (including Sr and Nd isotopes) of two lamprophyre dykes, intruding the Archaean granitic gneisses at Sivarampeta in the diamondiferous Wajrakarur kimberlite field (WKF), eastern Dharwar craton, southern India, are presented. The Sivarampeta lamprophyres display porphyritic-panidiomorphic texture comprising macrocrysts/phenocrysts of olivine, clinopyroxene (augite), and mica set in a groundmass dominated by feldspar and comprising minor amounts of ilmenite, chlorite, carbonates, epidote, and sulphides. Amphibole (actinolite-tremolite) is essentially secondary in nature and derived from the alteration of clinopyroxene. Mica is compositionally biotite and occurs as a scattered phase throughout. Mineralogy suggests that these lamprophyres belong to calc-alkaline variety whereas their bulk-rock geochemistry portrays mixed signals of both alkaline as well as calc-alkaline (shoshonitic) variety of lamprophyres and suggest their derivation from the recently identified Domain II (orogenic-anorogenic transitional type mantle source) from eastern Dharwar craton. Trace element ratios imply melt-derivation from an essentially the garnet bearing-enriched lithospheric mantle source region; this is further supported by their 87Sr/86Srinitial (0.708213 and 0.708507) and ‘enriched’ eNdinitial (-19.1 and -24.2) values. The calculated TDM ages (2.7-2.9 Ga) implies that such enrichment occurred prior to or during Neoarchean, contrary to that of the co-spatial and co-eval kimberlites which originated from an isotopically depleted mantle source which was metasomatized during Mesoproterozoic. The close association of calc-alkaline shoshonitic lamprophyres, sampling distinct mantle sources, viz., Domain I (e.g., Udiripikonda) and Domain II (Sivarampeta), and kimberlites in the WKF provide further evidence for highly heterogeneous nature of the sub-continental lithospheric mantle beneath the eastern Dharwar craton.
DS1975-1025
1979
Ragland, P.C.Galipeau, J.M., Ragland, P.C.Whole Rock Chemical Constraints on the Origin of the Virginia Dale Ring Dike Complex.Geochemical Journal, Vol. 13, No. 5, NOVEMBER PP. 207-216.United States, Colorado, Wyoming, State Line, Rocky MountainsGeochemistry
DS1992-1240
1992
Ragland, P.C.Puffer, J.H., Ragland, P.C.Eastern North American Mesozoic magmatismGeological Society of America Special Paper, No. 268, 420pAppalachiaMagmatism, Table of contents
DS200512-0073
2005
Ragland, P.C.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
DS2000-0554
2000
Ragnarsdottir, K.Law, K.M., Blundy, J.D., Wood, B.J., Ragnarsdottir, K.Trace element partioning between wollastonite and silicate carbonate meltMineralogical Magazine, Vol. 64, No. 4, Aug. pp. 651-62.GlobalGeochemistry, Carbonatite
DS1996-0858
1996
Ragnarsdottir, K.V.Lloyd, F.E., Edgar, A.D., Ragnarsdottir, K.V.light rare earth element (LREE) distribution in perovskite, apatite and titanite from southwestUgand an xenoliths and kamafugite lavas.Mineralogy and Petrology, Vol. 57, No. 3-4, pp. 205-228.UgandaPerovskite, Rare earths, xenoliths
DS2002-1297
2002
Ragnarsson, S.Ragnarsson, S., Stefansson, R.Plume driven plumbing and crustal formation in IcelandJournal of Geophysical Research, August 10: 1029/2001JB000584IcelandTectonics, Hot spots
DS201112-1156
2011
RagozinZedgenizov, D.A., Ragozin, Shatsky, Kagi, Odake, Griffin, Araujo, YuryevaEvidence for evolution of growth media in superdeep diamonds from Sao-Luis Brazil.Goldschmidt Conference 2011, abstract p.2244.South America, BrazilCl imaging
DS200812-1048
2008
Ragozin, A.Shatsky, V., Ragozin, A., Zedgenizov, D., Mityukhin, S.Evidence for multistage evolution in a xenolith of diamond bearing eclogite from the Udachnaya kimberlite pipe.Lithos, Vol. 105, 3-4, pp. 289-300.Russia, YakutiaDeposit - Udachnaya - distribution of diamonds
DS201312-1006
2014
Ragozin, A.Zedgenizov, D.A., Kagi, H., Shatsky, V.S., Ragozin, A.Local variations of carbon isotope composition in diamonds from Sao-Luis ( Brazil): evidence for heterogenous carbon reservoir in sublithospheric mantle.Chemical Geology, Vol. 363, pp. 114-124.South America, BrazilDeposit - Sao Luis area
DS201412-0436
2014
Ragozin, A.Kagi, H., Ishibashi, H., Zedgenizov, D., Shatsky, V., Ragozin, A.Growth condition of super-deep diamonds inferred from carbon isotopic compositions and chemical compositions of nano-inclusions.Goldschmidt Conference 2014, 1p. AbstractMantleMineral chemistry
DS201412-0469
2014
Ragozin, A.Kolesnichenko, M., Zedgenizov, D., Ragozin, A., Litasov, K.Water content in olivines of mantle xenoliths from Udachnaya kimberlite pipe, Yakutia.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 2p. AbstractRussia, YakutiaDeposit - Udachnaya
DS201603-0435
2016
Ragozin, A.Zedgenizov, D., Rubatto, D., Shatsky, V., Ragozin, A., Kalinina, V.Eclogitic diamonds from variable crustal protoliths in the northeastern Siberian Craton: trace elements and coupled Delta13C-delta 180 signatures in diamonds and garnet inclusions.Chemical Geology, Vol. 422, pp. 46-59.RussiaGeochronology
DS201808-1781
2017
Ragozin, A.Ragozin, A., Zedgenizov, D., Kuper, K., Palyanov, Y.Specific internal structure of diamonds from Zarnitsa kimberlite pipe.Crystals, Vol. 7, 5, pp. 133-Russiadeposit - Zarnitsa

Abstract: The Zarnitsa kimberlite pipe is one of the largest pipes of the Yakutian diamondiferous province. Currently, some limited published data exists on the diamonds from this deposit. Among the diamond population of this pipe there is a specific series of dark gray to black diamonds with transition morphologies between octahedron and rounded rhombic dodecahedron. These diamonds have specific zonal and sectorial mosaic-block internal structures. The inner parts of these crystals have polycrystalline structure with significant misorientations between sub-individuals. The high consistency of the mechanical admixtures (inclusions) in the diamonds cores can cause a high grid stress of the crystal structure and promote the block (polycrystalline) structure of the core components. These diamond crystals have subsequently been formed due to crystallization of bigger sub-individuals on the polycrystalline cores according to the geometric selection law.
DS201901-0059
2017
Ragozin, A.Ragozin, A., Zedgenizov, D., Kuper, K., Kalimina, V., Zemnukhov, A.The internal structure of yellow cuboid diamonds from alluvial placers of the northeastern Siberian platform.Crystals MDPI, Vol. 7, 8, 13p. Doi.org/10. 3390/cryst7080238Russiadiamond morphology

Abstract: Yellow cuboid diamonds are commonly found in diamondiferous alluvial placers of the Northeastern Siberian platform. The internal structure of these diamonds have been studied by optical microscopy, X-Ray topography (XRT) and electron backscatter diffraction (EBSD) techniques. Most of these crystals have typical resorption features and do not preserve primary growth morphology. The resorption leads to an evolution from an originally cubic shape to a rounded tetrahexahedroid. Specific fibrous or columnar internal structure of yellow cuboid diamonds has been revealed. Most of them are strongly deformed. Misorientations of the crystal lattice, found in the samples, may be caused by strains from their fibrous growth or/and post-growth plastic deformation.
DS201907-1572
2019
Ragozin, A.Shatsky, V., Jagoutz, E., Kozmenko, O., Ragozin, A., Skuzovatov, S., Sobolev, N.The protolith nature of diamondiferous metamorphic rocks of the Kokchetav Massif.Acta Geologica Sinica, Vol. 93, 1, p. 173-Russiadeposit - Kokchetav

Abstract: International Symposium on Deep Earth Exploration and Practices Beijing, China -October24-26, 2018The protolithnatureof diamondiferous metamorphic rocks of the Kokchetav MassifVladislav Shatsky1,2,3, Emil Jagoutz4, Olga Kozmenko1, Alexey Ragozin1,3, Sergei Skuzovatov2and Nikolai Sobolev1,31Sobolev Institute of Geology and Mineralogy SB RAS, Novosibirsk, 630090, Russia, Institute of Geochemistry SB RAS, Irkutsk, Russia3Novosibirsk State University, Novosibirsk, Russia4Max Planck Institute for Chemistry, Mainz, GermanyUltra-high-pressure diamondiferous rocks (UHP) of the Kokchetav subduction-collision zone are considered as an idealobject for studying the mobility of elements insubduction zones of the continental type. The compositional diversity of metasedimentary rocks subjected to UHP metamorphism makes it difficult to establish the nature of their protoliths. This, in turn, complicates estimatesof the degree of depletionof the UHP metamorphic rocks relative to the protoliths.To clarify the nature of protholiths of the Kokchetav diamondiferous rocks we studied the geochemical features and Sm-Nd isotopic composition of diamondiferous calc-silicate, garnet-pyroxene rocks, high-alumina metapelitesand barren granite-gneisses.The nine samples of the Kumdy Kol mocrodiamond deposit (one granite-gneiss, 4-calc-silicate rocks, 3-garnet-pyroxenite) yielded aSm-Nd whole-rockisochronageof 1052±44 Ma. This age is close to the age of formation of the granitic gneiss basement of the Kokchetav massif (1.2-1.05 Ga) (Glorie et al., 2015). Therefore, we assume that the protoliths of these rocks were basementrocks. In this interpretation, their geochemical features may not be directly related to the processes of ultrahigh-pressure metamorphism.At the same time, the high-alumina rocks of the Barchinsky area are depleted todifferent degreeswithrespect to LREE and K yieldeda whole-rockisochron with an age of 509 ± 32 Ma, which suggests partial melting of these rocks duringthe exhumation stage.It was previously assumed that metasedimentary rocks of the Kokchetav microcontinent are the protoliths of diamondiferous rocks (Buslov et al., 2015). However, this contradicts with Sm-Nd isotopic data for metasedimentary rocks of quartzite-schist sequences of the Kokchetav microcontinent (Kovach et al., 2017). The metasedimentary rocks of the Sharyk Formation are characterized by variations in the ?Nd(t)from +4.1 to -3.3 and intNd(DM)from 1.9 to 1.25 Ga, whereasin the UHP metamorphic rocks ?Nd(t)varies from -7.6 to -13.2, and the model ages range from 2.7 to 2.3 Ga. These data clearly indicate that the metasedimentary rocks of the Kokchetav massif could not be the protolith of the ultrahigh-pressure rocks.
DS201908-1813
2019
Ragozin, A.Shatsky, V., Zedgenizov, D., Ragozin, A., Kalinina, V.Silicate melt inclusions in diamonds of eclogite paragenesis from placers on the northeastern Siberian craton.Minerals, Vol. 9, 7, pp. 412 ( 11p)Russia, Siberiadeposit - Kholomolokh

Abstract: New findings of silicate-melt inclusions in two alluvial diamonds (from the Kholomolokh placer, northeastern Siberian Platform) are reported. Both diamonds exhibit a high degree of N aggregation state (60-70% B) suggesting their long residence in the mantle. Raman spectral analysis revealed that the composite inclusions consist of clinopyroxene and silicate glass. Hopper crystals of clinopyroxene were observed using scanning electron microscopy and energy-dispersive spectroscopic analyses; these are different in composition from the omphacite inclusions that co-exist in the same diamonds. The glasses in these inclusions contain relatively high SiO2, Al2O3, Na2O and, K2O. These composite inclusions are primary melt that partially crystallised at the cooling stage. Hopper crystals of clinopyroxene imply rapid cooling rates, likely related to the uplift of crystals in the kimberlite melt. The reconstructed composition of such primary melts suggests that they were formed as the product of metasomatised mantle. One of the most likely source of melts/fluids metasomatising the mantle could be a subducted slab.
DS201910-2297
2019
Ragozin, A.Shatsky, V., Ragozin, A., Logvinova, A., Wirth, R., Sobolev, N.Alluvial diamonds from iron-saturated mantle beneath the northeastern margin of Siberian craton.Goldschmidt2019, 1p. AbstractRussiacraton

Abstract: Diamonds of eclogitic paragenesis are dominant in the placer deposits in the northeastern part of the Siberian Craton. Multiple inclusions and host diamonds carbon isotopes composition are consistent with a mixing model in which they result from the interaction of slab-derived melt/fluid with surrounding mantle [1,2]. A significant portion of diamonds contains black inclusions usually interpreted as graphite or sulphides. Twenty six dark inclusions from the 22 diamonds were exposed by polishing for chemical microanalysis. Inclusions were studied with SEM, TEM and EMP. Fe-C-O melt inclusions in association with with Kfsp, Ol and silicate melt inclusions were identified. Most of the inclusions are heterogeneous in composition and consist of iron carbides, iron in various oxidation states and carbon. Carbides contain impurities of Ni (0-0.6%), Sr (up to 3.4%), Cr (up to 0.8%) Si (up to 1%). Inclusions of wustite and Fe-Ti-O melt were identified in one diamond along with inclusions of Fe-C-O melt. In two cases diamond inclusions found within host diamond crystal. Diamond inclusions are surronded by a border consisting of wustite and siderite. Inclusions of Fe-C-O melt in allivial diamonds are best explained by carbonate melt-iron reaction [3].
DS201911-2556
2019
Ragozin, A.Ragozin, A., Zedgenizov, D., Kagi, H., Kuper, K.E., Shatsky, V.Deformation features of superdeep diamonds.Goldschmidt2019, 1p. AbstractSouth America, Brazil, Russia, Siberiadeposit - Juina

Abstract: Much of our knowledge of the Earth’s deep interior comes from theoretical models, which are based on the results of experimental petrology and seismology. Diamonds in such models are the unique natural samples because they contain and preserve inclusions of mantle materials that have been entrapped during diamond growth and remained unchanged for long geologic time. In the present study for superdeep sublithospheric diamonds from Saõ-Luiz (Juina, Brazil) and northeastern Siberian Platform with mineral inclusions of the Transition Zone and Lower Mantle (majorite garnet, coesite (stishovite), ferropericlase and Mg-Si-, Ca-Si-, Ca-Ti, Ca-Si- Ti-perovskite), the diffraction of backscattered electrons technique (EBSD) revealed features of the internal structure. Superdeep diamonds are characterized by a defective and imperfect internal structure, which is associated with the processes of growth and post-growth plastic deformation. The deformation is manifested both in the form of stripes parallel to the (111) direction, and in the form of an unordered disorientation of crystal blocks up to 2°. In addition, for many crystals, a block structure was established with a greater disorientation of the sub-individuals, as well as the presence of “diamond-in-diamond” inclusions and microtwins. Additional stresses are often observed around inclusions associated with the high remaining internal pressure. It has previously been shown that the crystal structure of superdeep diamonds is significantly deformed around inclusions of perovskites, SiO2 (stishovite?), and Mg2SiO4 (ringwoodite?). The significant plastic deformations detected by the EBSD around inclusions testify to phase transitions in superdeep minerals (perovskites, stishovite, and ringwoodite) [1].
DS202004-0549
2020
Ragozin, A.Zedgenizov, D., Bogush, I., Shatsky, V., Kovalchuk, O., Ragozin, A., Kalinina, V.Mixed habit type Ib-IaA diamond from an Udachnaya eclogite.Minerals MDPI, Vol. 9, 9120741, 12p. PdfRussiadeposit - Udachnaya

Abstract: The variety of morphology and properties of natural diamonds reflects variations in the conditions of their formation in different mantle environments. This study presents new data on the distribution of impurity centers in diamond type Ib-IaA from xenolith of bimineral eclogite from the Udachnaya kimberlite pipe. The high content of non-aggregated nitrogen C defects in the studied diamonds indicates their formation shortly before the stage of transportation to the surface by the kimberlite melt. The observed sectorial heterogeneity of the distribution of C- and A-defects indicates that aggregation of nitrogen in the octahedral sectors occurs faster than in the cuboid sectors.
DS202006-0937
2020
Ragozin, A.Mikhailenko, D., Golovin, A., Korsakov, A., Aulbach, S., Gerdes, A., Ragozin, A.Metasomatic evolution of coesite-bearing diamondiferous eclogite from the Udachnaya kimberlite.Minerals, Vol. 10, 4, 24p. PdfRussia, Siberiadeposit - Udachnaya

Abstract: A coesite-bearing diamondiferous eclogite from the Udachnaya kimberlite (Daldyn field, Siberian craton) has been studied to trace its complex evolution recorded in rock-forming and minor mineral constituents. The eclogite sample is composed of rock-forming omphacite (60 vol%), garnet (35 vol%) and quartz/coesite (5 vol%) and contains intergranular euhedral zoned olivine crystals, up to 200 µm long, coexisting with phlogopite, orthopyroxene, clinopyroxene (secondary), K-feldspar, plagioclase, spinel, sodalite and djerfisherite. Garnet grains are zoned, with a relatively homogeneous core and a more magnesian overgrowth rim. The rim zones further differ from the core in having higher Zr/Y (6 times that in the cores), ascribed to interaction with, or precipitation from, a kimberlite-related melt. Judging by pressure-temperature estimates (~1200 °C; 6.2 GPa), the xenolith originated at depths of ~180-200 km at the base of the continental lithosphere. The spatial coexistence of olivine, orthopyroxene and coesite/quartz with K-Na-Cl minerals in the xenolith indicates that eclogite reacted with a deep-seated kimberlite melt. However, Fe-rich olivine, orthopyroxene and low-pressure minerals (sodalite and djerfisherite) likely result from metasomatic reaction at shallower depths during transport of the eclogite by the erupting kimberlite melt. Our results demonstrate that a mixed eclogitic-peridotitic paragenesis, reported previously from inclusions in diamond, can form by interaction of eclogite and a kimberlite-related melt.
DS202012-2256
2020
Ragozin, A.:.Zedgenizov, D.A., Skuzovatov, S.Y., Griffin, W.L., Pomazansky, B.S., Ragozin, A.:., Kalinina, V.V.Diamond forming HDFs tracking episodic mantle metasomatism beneath Nyurbinskaya kimberlite pipe (Siberian craton).Contributions to Mineralogy and Petrology, Vol. 175, 106, 21p. PdfRussiadeposit - Nyurbinskaya

Abstract: We present a new dataset on the composition of high-density fluids (HDFs) in cloudy (n?=?25), coated (n?=?10) and cuboid (n?=?10) diamonds from the Nyurbinskaya kimberlite pipe. These diamonds represent different populations each showing distinct growth histories. The cores of coated diamonds display multiple growth stages and contrasting sources of carbon. Fibrous coats and cuboid diamonds have similar carbon isotopes and nitrogen systematics, suggesting their formation in the last metasomatic events related to kimberlite magmatism, as is common for most such diamonds worldwide. The HDFs in most of these diamonds span a wide range from low-Mg carbonatitic to hydrous silicic compositions. The major- and trace-element variations suggest that the sources for such HDFs range in composition between the depleted mantle and more fertile mantle reservoirs. Hydrous-silicic HDFs could originate from a 13C-enriched source, which originates through subduction of crustal metasedimentary material. Percolation of such HDFs through carbonated eclogites and peridotites facilitates the formation of cuboid diamonds and fibrous coats in the mantle section beneath the corresponding area of the Siberian craton. Cloudy diamonds represent an apparently older population, reflecting continuous diamond formation predominantly from high-Mg carbonatitic HDFs that caused discrete episodes of diamond precipitation. Their high Mg# and enrichment in incompatible elements support a metasomatized peridotitic source for these HDFs.
DS200812-1122
2008
Ragozin, A.A.L.A.Stepanov, A.A.S.A., Shatsky, V.A.S.A., Zedgenisov, D.A.A.A., Ragozin, A.A.L.A.Chemical heterogeneity in the Diamondiferous eclogite xenolith from the Udachanya pipe.Doklady Earth Sciences, Vol. 419, 2, pp. 308-311.RussiaPetrology - Udachnaya
DS200812-1123
2008
Ragozin, A.A.L.A.Stepanov, A.A.S.A., Shatsky, V.A.S.A., Zedgenizov, D.A.A.A., Ragozin, A.A.L.A.Chemical heterogenity in the Diamondiferous eclogite xenolith from the Udachnaya kimberlite pipe.Doklady Earth Sciences, Vol. 419, 1, pp. 308-311.RussiaGeochemistry - Udachnaya
DS202109-1486
2021
Ragozin, A.I.Ragozin, A.I., Agashev, A.M., Zedgenizov, D.A., Denisenko, A.A.Evolution of the lithospheric mantle beneath the Nakyn kimberlite field: evidence from garnets in the peridotite xenoliths of the Nyurba and Botuoba pipes.Geochemistry International, Vol. 59, 8, pp. 743-756. pdfRussia, Siberiadeposit - Nyurba, Botuoba

Abstract: The paper presents data on garnets from serpentinized peridotite xenoliths in the Nyurba and Botuoba kimberlite pipes of the Nakyn kimberlite field. The major and trace-element compositions of the garnets were analyzed to determine their compositional specifics and genesis. Based on the REE content and chondrite-normalized distribution patterns, the garnets are divided into two types with sinusoidal ((Sm/Er)n > 1) and normal ((Sm/Er)n < 1) REE distribution patterns. In terms of the Y, Zr, Ti, and Eu relations, and the shape of REE distribution pattern, all the garnets correspond to garnets of metasomatized peridotites, except for one sample falling into the field of depleted garnets of harzburgite-dunite paragenesis. The geochemical characteristics of the garnets record two types of metasomatic agents: carbonatite/fluid for type 1 garnets and silicate/melt for type 2 garnets. The carbonatite metasomatic agent produced harzburgitic garnet and its further transformation into lherzolitic garnet. Silicate metasomatism, which led to the formation of the REE pattern of type 2 garnets, likely overprinted two different types of garnets and, respectively, gave two evolutionary trends. These are depleted residual garnets and type 1 garnets previously subjected to carbonatite metasomatism. The low Y and Th contents in combination with the low Ti/Eu ratios in garnets suggest a moderate reworking of lithospheric peridotites by silicate melts, which is consistent with the high diamond grade of the Nakyn kimberlite field.
DS200612-1272
2006
Ragozin, A.J.Shatsky, V.S., Ragozin, A.J., Sobolev, N.V.Some aspects of metamorphic evolution of ultrahigh pressure calc-silicate rocks.Russian Geology and Geophysics, Vol. 47, 1 pp. 105-119.MantleUHP
DS2002-1298
2002
Ragozin, A.L.Ragozin, A.L., Shatsky, V.S., Tylov, G.M., Goryainov, S.V.Coesite inclusions in rounded diamonds from placers of the northeastern Siberian Platform.Doklady, Vol.384,4, May-June, pp. 385-9.Russia, SiberiaAlluvials, Diamond - inclusions, coesite
DS200512-0968
2005
Ragozin, A.L.Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L., Mityukhin, S.I., Sobolev, N.V.Evidence for metasomatic formation of diamond in eclogite xenolith from the Udachnaya kimberlite pipe.Doklady Earth Sciences, Vol. 402, 4, pp. 587-90.Russia, YakutiaMetasomatism
DS200612-1121
2006
Ragozin, A.L.Ragozin, A.L., Shatsky, V.S., Zetgenizov, D.A., Mityukhin, S.I.Evidence for evolution of diamond crystallization medium in eclogite xenolith from the Udachnaya kimberlite pipe, Yakutia.Doklady Earth Sciences, Vol. 407A, 3, pp. 465-468.Russia, YakutiaDiamond morphology - Udachnaya
DS200612-1274
2006
Ragozin, A.L.Shatsky, V.S., Stepanov, A.S., Zedgenizov, D.A., Ragozin, A.L.Mineral inclusions in diamonds from chemically heterogeneous eclogite xenolith.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 25. abstract only.RussiaDiamond inclusions
DS200612-1275
2006
Ragozin, A.L.Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L.Evidence of mantle modification in Diamondiferous eclogite xenolith from Udachnaya kimberlite pipe, Yakutia.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 25. abstract only.Russia, YakutiaDeposit - Udachnaya, metasomatism
DS200712-0585
2007
Ragozin, A.L.Kuper, K.E., Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S., Porosev, V.V., Zolotarev, K.V., Baibchev, IvanovThree dimensional distribution of minerals in Diamondiferous eclogites, obtained by the method of high resolution X-ray computed tomography.Nuclear Instruments and Methods in Physics Research Section A., Vol. 575, 1-2, pp. 255-258.TechnologyDiamond genesis
DS200712-1218
2007
Ragozin, A.L.Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S.Chloride carbonate fluid in diamonds from the eclogite xenolith.Doklady Earth Sciences, Vol. 445, 6, pp. DOI:10.1134/S1028334 X07060293Russia, YakutiaGeochemistry
DS200912-0849
2009
Ragozin, A.L.Zedgenizov, D.A., Ragozin, A.L., Shjatsky, V.S., Araujo, D., Griffin, W.L., Kagi, H.Mg and Fe rich carbonate silicate high density fluids in cuboid diamonds from the Internationalnaya kimberlite pipe. Yakutia.Lithos, In press availableRussia, YakutiaDeposit - International
DS201012-0607
2009
Ragozin, A.L.Ragozin, A.L., Shatskii, V.S., Zedgenizov, D.A.New dat a on the growth environment of diamonds of the variety V from placers of the northeastern Siberian platform.Doklady Earth Sciences, Vol. 425, 2, April pp. 436-440.Russia, SiberiaAlluvials
DS201012-0691
2010
Ragozin, A.L.Shatskii, V.S., Zedgenizov, D.A., Ragozin, A.L.Majoritic garnets in diamonds from placers of the northeastern Siberian Platform.Doklady Earth Sciences, Vol. 432, 2, pp. 839-845.RussiaAlluvials
DS201012-0702
2010
Ragozin, A.L.Shiryaev, A.A., Safonov, O.G., Ragozin, A.L.XANES spectroscopy at the potassium K edge of inclusions in kimberlitic diamonds.International Mineralogical Association meeting August Budapest, abstract p. 186.Russia, South America, BrazilSpectroscopy
DS201112-0944
2011
Ragozin, A.L.Shatski, V.S., Zedgenizov, D.A., Ragozin, A.L., Kalinina, V.V., Reutskii, V.N.Local variations in carbon isotopes and nitrogen contents in diamonds from placers of the northeastern portion of the Siberian Platform.Doklady Earth Sciences, Vol. 440, 1, pp.Russia, SiberiaGeochronology
DS201112-0973
2011
Ragozin, A.L.Skuzovatov, S.Yu., Zedgenizov, D.A., Shatsky, V.S., Ragozin, A.L., Kuper, K.E.Composition of cloudy Micro inclusions in octahedral diamonds from the Internatsional'naya kimberlite pipe ( Yakutia).Russian Geology and Geophysics, Vol. 52, pp. 85-96.Russia, YakutiaDiamond morphology, inclusions
DS201212-0507
2012
Ragozin, A.L.Nadolinny, V.A., Yuryeva,O.P., Rakhmanova, M.I., Shatsky, V.S., Palyanov, Y.N., Kupriyanov, I.N., Zedgenizov, D.A., Ragozin, A.L.Distribution of OK1, N3 and NU1 defects in diamond crystals of different habits.European Journal of Mineralogy, Vol. 24, 4, pp. 645-650.TechnologyDiamond morphology
DS201212-0670
2012
Ragozin, A.L.Smelov, A.P., Shatsky, V.S., Ragozin, A.L., Reutskii, V.N., Molotkov, A.E.Diamondiferous Archean rocks of the Olondo greenstone belt ( western Aldan-Stanovoy shield).Russian Geology and Geophysics, Vol. 53, pp. 1012-1022.RussiaDiamond - genesis
DS201312-0729
2013
Ragozin, A.L.Ragozin, A.L., Shatsky, V.S., Zedgenizov, D.A., Griffin, W.L.Growth medium and carbon source of unusual rounded diamonds from alluvial placers of the north-east of Siberian platform.Goldschmidt 2013, AbstractRussia, SiberiaPlacers, alluvials
DS201312-0805
2013
Ragozin, A.L.Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L.Evidence for formation of alluvial diamonds from north-east of Siberian platform in subduction environment.Goldschmidt 2013, 1p. AbstractRussiaAlluvials
DS201312-0831
2012
Ragozin, A.L.Skuzovatov, S.Yu., Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S.Growth medium composition of coated diamonds from the Sytykanskaya kimberlite pipe ( Yakutia).Russian Geology and Geophysics, Vol. 53, 11, pp. 1197-1208.RussiaDeposit - Sytykanskaya
DS201312-0834
2012
Ragozin, A.L.Smelov, A.P., Shatsky, V.S., Ragozin, A.L., Reutskii, V.N., Molotkov, A.E.Diamondiferous Archean rocks of the Olondo greenstone belt ( western Aldan-Stanovoy shield).Russian Geology and Geophysics, Vol. 53, pp. 1012-1022.RussiaDiamond morphology
DS201312-1007
2013
Ragozin, A.L.Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S., Griffin, W.L.Parental growth media of Siberian diamonds - relation to kimberlites.Goldschmidt 2013, 1p. AbstractRussiaDiamond morphology
DS201412-0718
2014
Ragozin, A.L.Ragozin, A.L., Zedgenizov, D.A., Shatskii, V.S., Orihashi, Y., Agashev, A.M., Kagi, H.U Pb age of rutile from the eclogite xenolith of the Udachnaya kimberlite pipe.Doklady Earth Sciences, Vol. 457, 1, pp. 861-864.Russia, YakutiaDeposit - Udachnaya
DS201412-0801
2014
Ragozin, A.L.Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L., Kalinina, V.V.Carbon isotopes and nitrogen contents in placer diamonds from the NE Siberian craton: implications for diamond origins.European Journal of Mineralogy, Vol. 26, 1, pp. 41-52.RussiaAlluvials
DS201412-0802
2015
Ragozin, A.L.Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L., Kalinina, V.V.Diamondiferous subcontinental lithospheric mantle of the northeastern Siberian craton: evidence from mineral inclusions in alluvial diamonds.Gondwana Research, Vol. 28, 1, pp. 106-120.Russia, SiberiaMineral inclusions
DS201412-1023
2014
Ragozin, A.L.Zedgenizov, D.A., Shatskiy, A., Ragozin, A.L., Kagi, H., Shatsky, V.S.Merwinite in diamond from Sao Luiz, Brazil: a new mineral of the Ca-rich mantle environment.American Mineralogist, Vol. 99, pp. 547-550.South America, BrazilMineralogy
DS201502-0128
2015
Ragozin, A.L.Zedgenizov, D.A., Shatsky, V.S., Panin, A.V., Evtushenko, O.V., Ragozin, A.L., Kagi, H.Evidence for phase transitions in mineral inclusions in superdeep diamonds of the Sao Luiz deposit, Brazil.Russian Geology and Geophysics, Vol. 56, 1, pp. 296-305.South America, BrazilDeposit - Sao Luiz
DS201507-0335
2015
Ragozin, A.L.Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L., Kalinina, V.V.Diamondiferous subcontinental lithospheric mantle of the northeastern Siberian Craton: evidence from mineral inclusions in alluvial diamonds. Kapchan Fold Belt Olenek ProvinceGondwana Research, Vol. 28, 1, pp. 106-120.RussiaDiamond - inclusions
DS201509-0427
2015
Ragozin, A.L.Shatsky, V.S., Skuzovatov, S.Yu., Ragozin, A.L., Sobolev, N.V.Mobility of elements in a continental subduction zone: evidence from the UHP metamorphic complex of the Kokchetav massif.Russian Geology and Geophysics, Vol. 56, pp. 1016-1034.RussiaKokchetav massif

Abstract: We studied clastics of high-alumina garnet-kyanite-mica schists and garnet-kyanite-quartz granofelses, including diamond-bearing ones, found in the eluvial sediments near Lake Barchi. In contents of major elements the studied rocks correspond to argillaceous shales. The garnet-kyanite-quartz granofelses are poorer in K (0.49-1.35 wt.% K2O) than the garnet-kyanite-mica schists (4.9-2.2 wt.% K2O) but have the same contents of other major components. The REE patterns of most of the garnet-kyanite-phengite schists are similar to those of the Post-Archean Australian Shale (PAAS) (xLa/Yb = 13). All garnet-kyanite-quartz rocks are much stronger depleted in LREE (xLa/Yb = 1.4) and other incompatible elements. Our studies show that allanite and monazite are the main concentrators of LREE and Th in the garnet-kyanite-phengite rocks of the Barchi site. Monazite, occurring as inclusions in garnet, contains not only LREE but also Th, U, and Pb. Rutile of the nondepleted rocks is enriched in Fe and Nb impurities only. The garnet-kyanite-quartz granofelses bear rutile, apatite, and xenotime as accessory phases. Rutile of the depleted rocks shows wide variations in contents of Nb, Ta, and V impurities. In places, the contents of Nb and Ta reach 10.5 and 2.3 wt.%, respectively. The rutile decomposes into rutile with Nb (1.4 wt.%) and Fe (0.87 wt.%) impurities and titanium oxide rich in Fe (6.61 wt.%), Nb (up to 20.8 wt.%), and Ta (up to 2.81%) impurities. Based on the measured contents of incompatible elements in differently depleted high-alumina rocks, the following series of element mobility during UHP metamorphism has been established: Th > Ce > La > Pr > Nd > K > Ba > Rb > Cs > Sm > Eu. The contents of U, P, and Zr in the depleted rocks are similar to those in the nondepleted rocks. The studies have shown that metapelites subducted to the depths with diamond stability conditions can be depleted to different degrees. This might be either due to their exhumation from different depths of the subduction zone or to the presence of an external source of water controlling the temperature of dissolution of phengite and the formation of supercritical fluid/melt.
DS201610-1902
2016
Ragozin, A.L.Ragozin, A.L., Zedgenizov, D.A., Kuper, K.E., Shatsky, V.S.Radial mosaic internal structure of rounded diamond crystals from alluvial placers of Siberian platform. EbayakMineralogy and Petrology, in press available 15p.RussiaX-ray topography

Abstract: The specific gray to almost black diamonds of rounded morphology are especially typical in alluvial placers of the northeastern part of the Siberian platform. The results of study of internal structure of these diamonds are presented. X-ray topography and birefringence patterns of polished plates of studied diamonds show their radial mosaic structure. Diamonds consists of slightly misorientated (up to 20') subindividuals which are combined to mosaic wedge-shaped sectors. Electron back-scatter diffraction technique has demonstrated that subindividuals are often combined in the single large blocks (subgrains). The whole crystals commonly consist of several large subgrains misoriented up to 5° to one another. The total nitrogen content of these diamonds vary in the range 900-3300 ppm and nitrogen aggregation state (NB/(NB + NA)*100) from 25 to 64 %. Rounded diamond crystals of variety V are suggested to have been formed at the high growth rate caused by the high oversaturation of carbon in the crystallization medium. It may result in the splitting of growing crystal and their radial mosaic structure as a sequence. High content of structural nitrogen defects and the great number of mechanical impurities - various mineral and fluid inclusions may also favor to generation of this structure.
DS201610-1909
2016
Ragozin, A.L.Sobolev, N.V., Shatsky, V.S., Zedgenizov, D.A., Ragozin, A.L., Reutsky, V.N.Polycrystalline diamond aggregates from the Mir kimberlite pipe, Yakutia: evidence for mantle metasomatism.Lithos, in press available 10p.RussiaDeposit - Mir

Abstract: Polycrystalline diamond aggregates (boart, framesites, diamondites) have been widely studied but their origin is poorly understood. We report the results of a study in situ of two polished fragments of fine-grained (40-400 µm size of individual diamond grains) dense polycrystalline diamond aggregates from the Mir pipe containing visible multiple interstitial garnet inclusions. They were analyzed for major and trace elements of inclusions and one of them — for d13C and N abundance and isotopic composition of host diamonds. These aggregates are classified as variety IX by Orlov (1977). No cavities were observed in these samples. Sixty two irregular garnet grains and one clinopyroxene inclusion were detected and analyzed in sample Mr 832. Garnets are homogeneous within single grains but variable in Mg# [100Mg/(Mg + Fe)] from 60 up to 87 and CaO contents (3.3-5.3 wt.%) among grains with a trend to negative correlation. Low Cr (550-640 ppm) confirms eclogitic (E-type) paragenesis. High Na2O contents (5.2 wt.%) of a single pyroxene inclusion are additional evidence of eclogitic nature of this sample. Wide variations in trace elements (ppm) are characteristic for garnet grains: Sr (2.7-25.6), Y (9.7-14.1), Zr (15.6-38.7) and positive Eu anomaly is present. The d13C of diamonds within studied sample is variable (- 6.4 ÷- 9.8 ‰) as well as N abundance (75-1150 ppm) and d15N - 27, - 38, - 58 ‰. The second peridotitic (U/P-type) sample Mr 838 contains eight inclusions of Mg-rich Cr-pyropes (Mg# ~ 85, Cr2O3 3.2-3.4 wt.%) and magnesite inclusion with 4.35 wt.% FeO and 1.73 wt.% CaO. Trace element content in pyropes is relatively uniform (ppm): Sr (0.4-1.6), Y (13.2-13.4) and Zr (13.0). We conclude that heterogeneous distribution of the trace elements among garnet grains in Mr 832 and magnesite presence in Mr 838 are indicative of the effects of mantle metasomatism and rapid crystallization shortly before the eruption of the kimberlite.
DS201612-2327
2016
Ragozin, A.L.Ragozin, A.L., Palyanov, Yu.N., Zedgenizov, D.A., Kalinin, A.A., Shatsky, V.S.Homogenization of carbonate bearing Micro inclusions in diamond at P-T parameters of the upper mantle.Doklady Earth Sciences, Vol. 470, 2, pp. 1059-1062.RussiaDeposit - Internationalskaya

Abstract: The staged high-pressure annealing of natural cubic diamonds with numerous melt microinclusions from the Internatsional’naya kimberlite pipe was studied experimentally. The results mainly show that the carbonate phases, the daughter phases in partially crystallized microinclusions in diamonds, may undergo phase transformations under the mantle P-T conditions. Most likely, partial melting and further dissolution of dolomite in the carbonate-silicate melt (homogenization of inclusions) occur in inclusions. The experimental data on the staged high-pressure annealing of diamonds with melt microinclusions allow us to estimate the temperature of their homogenization as 1400-1500°C. Thus, cubic diamonds from the Internatsional’naya pipe could have been formed under quite high temperatures corresponding to the lithosphere/asthenosphere boundary. However, it should be noted that the effect of selective capture of inclusions with partial loss of volatiles in relation to the composition of the crystallization medium is not excluded during the growth. This may increase the temperature of their homogenization significantly between 1400 and 1500°C.
DS201702-0222
2017
Ragozin, A.L.Kolesnichenko, M.V., Zedgenizov, D.A., Litasov, K.D., Safonova, I.Y., Ragozin, A.L.Heterogenesous distribution of water in the mantle beneath the central Siberian Craton: implications for Udachnaya kimberlite pipe.Gondwana Research, in press available 18p.RussiaDeposit - Udachnaya

Abstract: The paper presents new petrographic, major element and Fourier transform infrared (FTIR) spectroscopy data and PT-estimates of whole-rock samples and minerals of a collection of 19 relatively fresh peridotite xenoliths from the Udachnaya kimberlite pipe, which were recovered from its deeper levels. The xenoliths are non-deformed (granular), medium-deformed and highly deformed (porphyroclastic, mosaic-porphyroclastic, mylonitic) lherzolites, harzburgite and dunite. The lherzolites yielded equilibration temperatures (T) and pressures (P) ranging from 913 to 1324 °C and from 4.6 to 6.3 GPa, respectively. The non-deformed and medium-deformed peridotites match the 35 mW/m2 conductive continental geotherm, whereas the highly deformed varieties match the 45 mW/m2 geotherm. The content of water spans 2 ± 1-95 ± 52 ppm in olivine, 1 ± 0.5-61 ± 9 ppm in orthopyroxene, and 7 ± 2-71 ± 30 ppm in clinopyroxene. The amount of water in garnets is negligible. Based on the modal proportions of mineral phases in the xenoliths, the water contents in peridotites were estimated to vary over a wide range from < 1 to 64 ppm. The amount of water in the mantle xenoliths is well correlated with the deformation degree: highly deformed peridotites show highest water contents (64 ppm) and those medium-deformed and non-deformed contain ca. 1 ppm of H2O. The high water contents in the deformed peridotites could be linked to metasomatism of relatively dry diamondiferous cratonic roots by hydrous and carbonatitic agents (fluids/melts), which may cause hydration and carbonation of peridotite and oxidation and dissolution of diamonds. The heterogeneous distribution of water in the cratonic mantle beneath the Udachnaya pipe is consistent with the models of mantle plume or veined mantle structures proposed based on a trace element study of similar xenolithic suits. Mantle metasomatism beneath the Siberian Craton and its triggered kimberlite magmatism could be induced by mantle enrichment in volatiles (H2O, CO2) supplied by numerous subduction zones which surrounded the Siberian continent in Neoproterozoic-Cambrian time.
DS201706-1086
2017
Ragozin, A.L.Kolesnichenko, M.V., Zedgenizov, D.A., Litasov, K.D., Safonova, I.Y., Ragozin, A.L.Heterogeneous distribution of water in the mantle beneath the central Siberian craton: implications from the Udachachnaya kimberlite pipe.Gondwana Research, Vol. 47, pp. 249-266.Russiadeposit - Udachnaya

Abstract: The paper presents new petrographic, major element and Fourier transform infrared (FTIR) spectroscopy data and PT-estimates of whole-rock samples and minerals of a collection of 19 relatively fresh peridotite xenoliths from the Udachnaya kimberlite pipe, which were recovered from its deeper levels. The xenoliths are non-deformed (granular), medium-deformed and highly deformed (porphyroclastic, mosaic-porphyroclastic, mylonitic) lherzolites, harzburgite and dunite. The lherzolites yielded equilibration temperatures (T) and pressures (P) ranging from 913 to 1324 °C and from 4.6 to 6.3 GPa, respectively. The non-deformed and medium-deformed peridotites match the 35 mW/m2 conductive continental geotherm, whereas the highly deformed varieties match the 45 mW/m2 geotherm. The content of water spans 2 ± 1-95 ± 52 ppm in olivine, 1 ± 0.5-61 ± 9 ppm in orthopyroxene, and 7 ± 2-71 ± 30 ppm in clinopyroxene. The amount of water in garnets is negligible. Based on the modal proportions of mineral phases in the xenoliths, the water contents in peridotites were estimated to vary over a wide range from < 1 to 64 ppm. The amount of water in the mantle xenoliths is well correlated with the deformation degree: highly deformed peridotites show highest water contents (64 ppm) and those medium-deformed and non-deformed contain ca. 1 ppm of H2O. The high water contents in the deformed peridotites could be linked to metasomatism of relatively dry diamondiferous cratonic roots by hydrous and carbonatitic agents (fluids/melts), which may cause hydration and carbonation of peridotite and oxidation and dissolution of diamonds. The heterogeneous distribution of water in the cratonic mantle beneath the Udachnaya pipe is consistent with the models of mantle plume or veined mantle structures proposed based on a trace element study of similar xenolithic suits. Mantle metasomatism beneath the Siberian Craton and its triggered kimberlite magmatism could be induced by mantle enrichment in volatiles (H2O, CO2) supplied by numerous subduction zones which surrounded the Siberian continent in Neoproterozoic-Cambrian time.
DS201801-0060
2018
Ragozin, A.L.Shatsky, V.S., Malkovets, V.G., Belousova, E.A., Tretiakova, I.G., Griffin, W.L., Ragozin, A.L., Wang, Q., Gibsher, A.A., O'Reilly, S.Y.Multi-stage modification of Paleoarchean crust beneath the Anabar tectonic province ( Siberian craton).Precambrian Research, Vol. 305, pp. 125-144.Russiacraton - Siberian

Abstract: According to present views, the crustal terranes of the Anabar province of the Siberian craton were initially independent blocks, separated from the convecting mantle at 3.1 (Daldyn terrane), 2.9 (Magan terrane) and 2.5?Ga (Markha terrane) (Rosen, 2003, 2004; Rosen et al., 1994, 2005, 2009). Previous studies of zircons in a suite of crustal xenoliths from kimberlite pipes of the Markha terrane concluded that the evolution of the crust of the Markha terrane is very similar to that of the Daldyn terrane. To test this conclusion we present results of U-Pb and Hf-isotope studies on zircons in crustal xenoliths from the Zapolyarnaya kimberlite pipe (Upper Muna kimberlite field), located within the Daldyn terrane, and the Botuobinskaya pipe (Nakyn kimberlite field) in the center of the Markha terrane. The data on xenoliths from the Botuobinskaya kimberlite pipe record tectonothermal events at 2.94, 2.8, 2.7 and 2?Ga. The event at 2?Ga caused Pb loss in zircons from a mafic granulite. U-Pb dating of zircons from the Zapolyarnaya pipe gives an age of 2.7?Ga. All zircons from the studied crustal xenoliths have Archean Hf model ages ranging from 3.65 to 3.11?Ga. This relatively narrow range suggests that reworking of the ancient crust beneath the Nakyn and Upper Muna kimberlite fields was minor, compared with the Daldyn and Alakit-Markha fields (Shatsky et al., 2016). This study, when combined with dating of detrital zircons, implies that tectonic-thermal events at 2.9-2.85, 2.75-2.7 and 2.0-1.95?Ga occurred everywhere on the Anabar tectonic province, and could reflect the upwelling of superplumes at 2.9, 2.7 and 2?Ga. The presence of the same tectonic-thermal events in the Daldyn and Markha terranes (Rosen et al., 2006a,b) supports the conclusion that the identification of the Markha terrane as a separate unit is not valid.
DS201806-1241
2018
Ragozin, A.L.Ragozin, A.L., Zedgenizov, D.A., Shatsky, V.S., Kuper, K.E.Formation of mosaic diamonds from the Zarnitsa kimberlite.Russian Geology and Geophysics, Vol. 59, pp. 486-498.Russiadeposit - Zarnitsa

Abstract: Mosaic diamonds from the Zarnitsa kimberlite (Daldyn field, Yakutian diamondiferous province) are morphologicaly and structurally similar to dark gray mosaic diamonds of varieties V and VII found frequently in placers of the northeastern Siberian craton. However, although being similar in microstructure, the two groups of diamonds differ in formation mechanism: splitting of crystals in the case of placer diamonds (V and VII) and growth by geometric selection in the Zarnitsa kimberlite diamonds. Selective growth on originally polycrystalline substrates in the latter has produced radial micro structures with grains coarsening rimward from distinctly polycrystalline cores. Besides the formation mechanisms, diamonds of the two groups differ in origin of mineral inclusions, distribution of defects and nitrogen impurity, and carbon isotope composition. Unlike the placer diamonds of varieties V and VII, the analyzed crystals from the Zarnitsa kimberlite enclose peridotitic minerals (olivines and subcalcic Cr-bearing pyropes) and have total nitrogen contents common to natural kimberlitic diamonds (0 to 1761 ppm) and typical mantle carbon isotope compositions (-1.9 to -6.2%c 513C; -4.2%c on average). The distribution of defect centers in the Zarnitsa diamond samples fits the annealing model implying that nitrogen aggregation decreases from core to rim.
DS201808-1788
2018
Ragozin, A.L.Shatsky, V.S., Malkovets, V.G., Belousova, E.A., Tretiakova, I.G., Griffin, W.L., Ragozin, A.L., Wang, Q., Gibsher, A.A., O'Reilly, S.Y.Multi stage modification of Paleoarchean crust beneath the Anabar tectonic provnce ( Siberian craton).Precambrian Research, Vol. 305, pp. 125-144.Russiatectonics

Abstract: According to present views, the crustal terranes of the Anabar province of the Siberian craton were initially independent blocks, separated from the convecting mantle at 3.1 (Daldyn terrane), 2.9 (Magan terrane) and 2.5?Ga (Markha terrane) (Rosen, 2003, 2004; Rosen et al., 1994, 2005, 2009). Previous studies of zircons in a suite of crustal xenoliths from kimberlite pipes of the Markha terrane concluded that the evolution of the crust of the Markha terrane is very similar to that of the Daldyn terrane. To test this conclusion we present results of U-Pb and Hf-isotope studies on zircons in crustal xenoliths from the Zapolyarnaya kimberlite pipe (Upper Muna kimberlite field), located within the Daldyn terrane, and the Botuobinskaya pipe (Nakyn kimberlite field) in the center of the Markha terrane. The data on xenoliths from the Botuobinskaya kimberlite pipe record tectonothermal events at 2.94, 2.8, 2.7 and 2?Ga. The event at 2?Ga caused Pb loss in zircons from a mafic granulite. U-Pb dating of zircons from the Zapolyarnaya pipe gives an age of 2.7?Ga. All zircons from the studied crustal xenoliths have Archean Hf model ages ranging from 3.65 to 3.11?Ga. This relatively narrow range suggests that reworking of the ancient crust beneath the Nakyn and Upper Muna kimberlite fields was minor, compared with the Daldyn and Alakit-Markha fields (Shatsky et al., 2016). This study, when combined with dating of detrital zircons, implies that tectonic-thermal events at 2.9 -2.85, 2.75 -2.7 and 2.0 -1.95?Ga occurred everywhere on the Anabar tectonic province, and could reflect the upwelling of superplumes at 2.9, 2.7 and 2?Ga. The presence of the same tectonic-thermal events in the Daldyn and Markha terranes (Rosen et al., 2006a,b) supports the conclusion that the identification of the Markha terrane as a separate unit is not valid.
DS201810-2339
2018
Ragozin, A.L.Kolesnichenko, M.V., Zedgenizov, D.A., Ragozin, A.L., Litasov, K.D., Shatsky, V.S.The role of eclogites in the redistribution of water in the subcontinental mantle of the Siberian craton: results of determination of the water content in minerals from the Udachnaya pipe eclogites.Russian Geology and Geophysics, Vol. 59, 7, pp. 763-779.Russia, Siberiadeposit - Udachnaya

Abstract: A comprehensive study of 26 mafic mantle xenoliths from the Udachnaya kimberlite pipe was carried out. The contents of major and trace elements, equilibrium temperature parameters, and water content in the rock-forming minerals were determined. The temperatures of formation of the studied rocks are estimated at 800-1300 °C. According to IR spectroscopy data, the water content in clinopyroxenes from the studied eclogites varies from values below the detection limit to 99 ppm. The IR spectra of garnets lack bands of water. The water content in clinopyroxene and orthopyroxene from garnet websterite is 72 and 8 ppm, respectively. The water content in the average rock, calculated from the ratio of the rock-forming minerals, varies from a few to 55 ppm. No relationship among the water content, equilibrium temperatures, and rock composition is established. The low water contents in the eclogites are close to the earlier determined water contents in peridotites from the same pipe and are, most likely, due to the re-equilibration of the eclogites with the rocks of the peridotitic lithospheric mantle. The dehydration of the protolith during its subduction and the partial melting of eclogites before their removal by kimberlitic magma to the surface might be an additional cause of the low water contents in the mantle eclogite xenoliths.
DS201811-2622
2018
Ragozin, A.L.Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S., Griffin, W.L.Diamond formation during metasomatism of mantle eclogite by chloride-carbonate melt.Contributions to Mineralogy and Petrology, Vol. 173, 16p. Doi.org/10.1007/s00410-018-1513-yRussiadeposit - Udachnaya

Abstract: A xenolith of bimineralic eclogite from the Udachnaya kimberlite pipe provides a snapshot of interaction between mantle rocks and diamond-forming fluids/melts. The major-element composition of the eclogite is similar to that of N-MORB and/or oceanic gabbros, but its trace-element pattern shows the effects of mantle metasomatism, which resulted in diamond formation. The diamonds are clustered in alteration veins that crosscut primary garnet and clinopyroxene. The diamonds contain microinclusions of a fluid/melt dominated by carbonate and KCl. Compared to the worldwide dataset, the microinclusions in these diamonds fall in middle of the range between saline fluids and low-Mg carbonatitic melts. The fluid/melt acted as a metasomatic agent that percolated through ancient eclogitic rocks stored in the mantle. This interaction is consistent with calculated partition coefficients between the rock-forming minerals and diamond-forming fluid/melt, which are similar to experimentally-determined values. Some differences between the calculated and experimental values may be due to the low contents of water and silicates in the chloride-carbonate melt observed in this study, and in particular its high contents of K and LILE. The lack of nitrogen aggregation in the diamonds implies that the diamond-forming metasomatism took place shortly before the eruption of the kimberlite, and that the microinclusions thus represent saline carbonate-rich fluids circulating in the basement of lithospheric mantle (150-170 km depth).
DS201908-1814
2019
Ragozin, A.L.Shatsky, V.S., Wang, Q., Skuszovatov, S.Y., Ragozin, A.L.The crust mantle evolution of the Anabar tectonic province in the Siberian craton: coupled or decoupled?Precambrian Research, Vol. 332, 105388 15p. Russia, Siberiadeposit - Udachnaya, Zarnitsa, Komsomolskaya

Abstract: To clarify the tectonic-thermal evolution of the Anabar tectonic province in the central Siberian Craton, we performed an isotope-geochemical study of 20 xenoliths from the Udachnaya, Zarnitsa, and Komsomolskaya kimberlite pipes to represent different crustal levels. Most mafic granulites have Proterozoic Nd model ages and geochemical characteristics close to those of intraplate basalts, whereas some mafic and intermediate granulites with Archean model ages exhibit geochemical features of supra-subduction ophiolitic basalts. Analysis of U-Pb ages and hafnium isotopic composition of zircon indicates that the main tectonic-thermal events modified the crust at 2.7 and 1.9-1.8?Ga, which is consistent with ages of mantle depletion events from previous studies. All zircons have Archean Hf model ages (3.2?Ga). Overall, thermal events with ages of 2.9-2.8, 2.7, 2.4, 1.97 and 1.8?Ga have remarkable influence on the studied zircons. Tectono-thermal events at 2.4 1.97, 1.9 and 1.8?Ga with no addition of juvenile material are recorded by zircons from xenoliths of mafic and intermediate granulites and metadiorites. A compilation of isotope-geochemical data demonstrates that instead of age-stratified, the crust of the Anabar tectonic province consists of variably reworked Paleoarchean rocks and juvenile Proterozoic rocks at all crustal levels. Hence the crust and mantle of the Siberian Craton has been coupled since the Paleoarchean.
DS201910-2312
2019
Ragozin, A.L.Zedgenizov, D.A., Ragozin, A.L., Kagi, H., Yurimoto, H., Shatsky, V. S.SiO2 inclusions in sublithospheric diamonds.Geochemistry International, Vol. 57, 9, pp. 964-972.Mantlediamond inclusions

Abstract: The paper describes mineralogical characteristics of SiO2 inclusions in sublithospheric diamonds, which typically have complicated growth histories showing alternating episodes of growth, dissolution, and postgrowth deformation and crushing processes. Nitrogen contents in all of the crystals do not exceed 71 ppm, and nitrogen is detected exclusively as B-defects. The carbon isotope composition of the diamonds varies from d13? = -26.5 to -6.7‰. The SiO2 inclusions occur in association with omphacitic clinopyroxenes, majoritic garnets, CaSiO3, jeffbenite, and ferropericlase. All SiO2 inclusions are coesite, which is often associated with micro-blocks of kyanite in the same inclusions. It was suggested that these phases have been produced by the retrograde dissolution of primary Al-stishovite, which is also evidenced by the significant internal stresses in the inclusions and by deformations around them. The oxygen isotope composition of SiO2 inclusions in sublithospheric diamonds (d18O up to 12.9‰) indicates a crustal origin of the protoliths. The negative correlation between the d18O of the SiO2 inclusions and the d13C of their host diamonds reflects interaction processes between slab-derived melts and reduced mantle rocks at depths greater than 270 km.
DS202005-0760
2020
Ragozin, A.L.Shatsky, V.S., Ragozin, A.L., Logvinova, A.M., Wirth, R.Diamond-rich placer deposits from iron-saturated mantle beneath the northeastern margin of the Siberian craton.Lithos, Vol. 364-365, 12p. PdfRussiadeposit - Olenek

Abstract: We demonstrate for the first time the presence of iron carbides in placer diamonds from the northeastern region of the Siberian craton. It was found that the inclusions are polycrystalline aggregates, and iron carbides filling the fissures in the diamonds, thus providing clear evidence that the iron melts were captured first. Iron carbides were identified in diamonds containing mineral inclusions of eclogitic (Kfs, sulfide) and peridotitc (olivine) paragenesis. Iron carbides with minor amounts of admixed nickel were detected in a diamond sample containing an olivine inclusion (0.3 wt% Ni), indicating that the iron melt was not in equilibrium with the mantle peridotite.The low nickel contents of the iron carbides provide the best evidence that the subducted crust is a likely source of the iron melt. Diamonds containing carbide inclusions are characterised by a relatively low nitrogen aggregation state (5-35%), which is not consistent with the high temperature of the transition zone. Therefore, we have reason to assume that the studied diamonds are from the lower regions of the lithosphere. Considering all factors, the model for the interaction of the ascending asthenospheric mantle with the subducting slab seems to be more realistic.
DS202010-1876
2020
Ragozin, A.L.Shatsky, V.S., Ragozin, A.L., Kozmenko, O.A., Denisenko, A.A.Geochemical evidence for participation of the subducted crust in the process of transformation of the subcontinental mantle in the Yakutian diamondiferous province.Doklady Earth Sciences, Vol. 493, 1, pp. 513-516. pdfRussia, Yakutiasubduction

Abstract: The data available indicate the complex evolution of deformed peridotites of mantle xenoliths, the P-T parameters of which indicate that they are fragments of the metasomatized lower part of the cratonic lithosphere. The zoning established in garnets from xenoliths in kimberlite pipes is interpreted as a result of metasomatism that occurred shortly before xenoliths reached the surface. Metasomatic alterations in xenoliths of deformed harzburgites were manifested not only in the development of zoning of minerals. The study results show that there is a discrepancy between the data calculated based on the contents of incompatible elements in minerals of xenoliths and those obtained due to direct measurements of the bulk composition of xenoliths. To determine the balance of incompatible elements, we have carried out experiments on leaching xenoliths of deformed lherzolites from the Udachnaya kimberlite pipe. It was established that a significant part of LREEs in the studied xenoliths occurs in the intergranular space. The distribution pattern of incompatible elements and, in particular, the presence of a positive Eu anomaly indicate that the appearance of the intergranular component is not associated with contamination of xenoliths by the kimberlite melt. Quite a few xenoliths demonstrate a positive Eu anomaly, which indicates the influence of the subducted crustal component at one of the modification stages of xenoliths.
DS202011-2070
2020
Ragozin, A.L.Zemnukhov, A.L., Reutsky, V.N., Zedgenizov, D.A., Ragozin, A.L., Zhelonkin, R.Y., Kalinina, V.V.Subduction related population of diamonds in Yakutian placers, northeastern Siberian platform.Contributions to Mineralogy and Petrology, Vol. 175, 98 10.1007/s00410-020-01741-w 11p. PdfRussia, Yakutiadiamond crystallography

Abstract: The 35 paired diamond intergrowths of rounded colorless transparent and gray opaque crystals from the placers of northeastern Siberian Platform were investigated. Mineral inclusions (KFsp, Coe, E-Grt, Po) detected in studied samples belong to eclogitic paragenesis. The majority of studied samples have uniform ranges of nitrogen content (1126-1982 at. ppm) and carbon isotope composition (-?16.8 to -?23.2 ‰). These characteristics pointing towards subducted material are possible sources for their genesis. Two samples consist of a gray opaque crystal with the subduction-related characteristics (d13C ca. -?21‰ and N ca. 1300 at. ppm) and a transparent crystal with low nitrogen content (412 and 29 at. ppm) and a heavy carbon isotopic composition (d13C -?4.2 and -?4.6‰) common for primary mantle range. The higher degree of nitrogen aggregation in the crystals with mantle-like characteristics testifies their longer storage in the mantle conditions. These samples reflect multistage diamond growth history and directly indicate the mixing of mantle and subduction carbon sources at the basement of subcontinental lithospheric mantle of northeastern Siberian Platform.
DS202102-0224
2020
Ragozin, A.L.Skuzovatov, S.Yu., Shatsky, V.S., Ragozin, A.L., Wang, K-L.Ubiquitous post-peak zircon in an eclogite from the Kumdy-Kol, Kokchetav UHP-HP massif ( Kazakhstan): significance of exhumation-related zircon growth and modification in continental-subduction settings.Island Arc, doi:10.1111/ iar.12385 29p. PdfRussia, Kazakhstandeposit - Kumby-Kol

Abstract: U-Pb geochronological, trace-element and Lu-Hf isotopic studies have been made on zircons from ultrahigh-pressure (UHP) mafic eclogite from the Kumdy-Kol area, one of the diamond-facies domains of the Kokchetav Massif (northern Kazakhstan). The peak eclogitic assemblage equilibrated at >?900?°C, whereas the bulk sample composition displays light rare-earth element (LREE) and Th depletion evident of partial melting. Zircons from the eclogite are represented by exclusively newly formed metamorphic grains and have U-Pb age spread over 533-459?Ma, thus ranging from the time of peak subduction burial to that of the late post-orogenic collapse. The major zircon group with concordant age estimates have a concordia age of 508.1?±4.4?Ma, which corresponds to exhumation of the eclogite-bearing UHP crustal slice to granulite- or amphibolite-facies depths. This may indicate potentially incoherent exhumation of different crustal blocks within a single Kumdy-Kol UHP domain. Model Hf isotopic characteristics of zircons (eHf(t) +1.5 to +7.8, Neoproterozoic model Hf ages of 1.02-0.79?Ga) closely resemble the whole-rock values of the Kumdy-Kol eclogites and likely reflect in situ derivation of HFSE source for newly formed grains. The ages coupled with geochemical systematics of zircons confirm that predominantly late zircon growth occurred in Th-LREE-depleted eclogitic assemblage, that experienced incipient melting and monazite dissolution in melt at granulite-facies depths, followed by amphibolite-facies rehydration during late-stage exhumation-related retrogression.
DS202107-1127
2021
Ragozin, A.L.Shatsky, V.S., Ragozin, A.L., Skuzovatov, S. Yu., Kozmenko, O.A., Yagoutz, E.Isotope-geochemical evidence of the nature of protoliths of diamondiferous rocks of the Kokchetav subduction-collision zone ( northern Kazakhstan).Russian Geology and Geophysics, Vol. 62, pp. 547-556, pdfRussia, Kazakhstandeposit - Kokchetav

Abstract: The isotope-geochemical features of diamondiferous metamorphic rocks of the Kokchetav subduction–collision zone (KSCZ) show that both the basement rocks and the sediments of the Kokchetav massif were their protoliths. A whole-rock Sm–Nd isochron from the diamondiferous calc-silicate, garnet–pyroxene rocks and migmatized granite-gneisses of the western block of the KSCZ yielded an age of 1116 ± 14 Ma, while an age of 1.2–1.1 Ga was obtained by U–Pb dating of zircons from the granite-gneiss basement of the Kokchetav microcontinent. Based on these data, we assume that the protoliths of the calc-silicate, garnet–pyroxene rocks and the granite-gneisses of the KSCZ were the basement rocks sharing an initially single Nd source, which was not influenced by high- to ultrahigh-pressure metamorphism (~530 Ma). Therefore, their geochemical features are probably not directly related to ultrahigh-pressure metamorphism. The corresponding rock associations lack isotope-geochemical evidence of partial melting that would occur during ultrahigh-pressure metamorphism, which suggesting that they were metamorphosed under granulite-facies conditions. At the same time, the high-alumina diamondiferous rocks of the Barchi area (garnet–kyanite–mica schists and granofelses), which were depleted to different degrees in light rare-earth elements (REE) and K, have yielded a Sm–Nd whole-rock isochron age of 507 ± 10 Ma indicating partial melting of these rocks during their exhumation stage. The close ?Nd (1100) values of the basement rocks and garnet–kyanite–mica schist with geochemical characteristics arguing against its depletion during high-pressure metamorphism indicate that the basement rocks were a crustal source for high-alumina sediments.
DS201112-0012
2010
Rahal Lenharo, S.L.Alencar de Carvalho Borges, M.P., Rahal Lenharo, S.L.Mineralogia dos diamantes da terra indigena Roosevelt-ro e implicacoes para a proveniencia e genese.5th Brasilian Symposium on Diamond Geology, Nov. 6-12, abstract p. 52.South America, RondoniaOverview of area
DS201012-0418
2010
Raharimahefa, T.Kusky, T.M., Toraman, E., Raharimahefa, T., Rasoazanamparany, C.Active tectonics of the Alatra Ankay graben system, Madagascar: possible extension of Somalian African diffusive plate boundary?Gondwana Research, Vol. 18, 2-3, pp. 274-294.Africa, MadagascarTectonics
DS1998-1202
1998
Rahe, B.Rahe, B., Ferrill, D.A., Morris, A.P.Physical analog modeling of pull apart basin evolutionTectonophysics, Vol. 285, No. 1-2, Feb. 15, pp. 21-86GlobalBasin, Tectonics, structure, model
DS200912-0608
2008
Rahfeldt, T.Rahfeldt, T., Foley, S.F., Jacob, D.E., Carlson, R.W., Lowry, D.Contrasting types of metasomatism in dunite, wherlite and websterite xenoliths from Kimberley, South Africa.Geochimica et Cosmochimica Acta, Vol. 72, 5722-36.Africa, South AfricaDeposit - Kimberley
DS201412-0869
2014
Rahgoshay, M.Soltanmohammadi, A., Rahgoshay, M., Ceuleneer, G.Clinopyroxene composition of mafic-ultramafic xenoliths in alkaline rocks, northwestern Iran: an example of cognate type xenoliths in lamprophyres.30th. International Conference on Ore Potential of alkaline, kimberlite and carbonatite magmatism. Sept. 29-, IranXenoliths
DS2002-1299
2002
Rahl, J.M.Rahl, J.M.,McGrew, A.J., Foland, K.A.Transition from contraction to extension in the northeastern Basin and Range: new evidence from...Journal of Geology, Vol.110,1,pp. 179-94.NevadaTectonics, Copper Mountains area
DS2000-0791
2000
Rahmanov, K.Rahmanov, K.Potassic alkaline basaltoids of the Middle Tien Shan. ( Chatkal and KouramaIgc 30th. Brasil, Aug. abstract only 1p.ChinaShoshonite
DS202007-1176
2019
RaiSaha, G., Rai, S,S., ShalivahanOccurrence of diamond in peninsular India and its relationship with deep Earth seismic properties.Journal of Earth System Science, Vol. 128, 43, 8p. PdfIndiageophysics, seismics

Abstract: An improved shear wave velocity (Vs) structure of the lithosphere of peninsular India using the surface wave tomography from the ambient noise and earthquake waveforms suggests its bipolar character. While most of the geological domains of India are characterised by a uniform lithospheric mantle of Vs~4.5 km/s, the three cratonic regions, eastern Dharwar, Bastar and Singhbhum, hosting most of the diamondiferous kimberlite fields, show significantly high Vs of 4.7 km/s and above in their lower lithosphere beyond ~90 km depth. The higher velocity could best be explained by the presence of diamond and/or eclogite along with peridotite in mantle. This unique relationship suggests the regional seismic image of lithosphere as a guide for exploration of diamonds.
DS200912-0609
2009
Rai, A.Rai, A., Gaur, V.K., Rai, S.S., Preistley, K.Seismic signatures of the Pan-African orogeny: implications for southern Indian high grade terranes.Geophysical Journal International, Vol. 176, 2, pp. 518-528.IndiaUHP
DS201905-1070
2019
Rai, A.K.Rai, A.K., Srivastava, R.K., Samal, A.K., Sesha Sai, V.V.Geochemistry, petrogenesis, and geodynamic implications of NE-SW to ENE - WSW trending Paleoproterozoic mafic dyke swarms from southern region of the western Dharwar Craton.Geological Journal, Doi: 10.1002/gj.3493Indiageodynamics

Abstract: A number of NE-SW to ENE-WSW trending Palaeoproterozoic mafic dykes, intruded within the Archean basement rocks and more conspicuous in the southern parts of the western Dharwar Craton (WDC), was studied for their whole-rock geochemistry to understand their petrogenetic and geodynamic aspects. Observed mineralogical and textural characteristics classify them either as meta-dolerites or dolerites/olivine-dolerites. They show basaltic to basaltic-andesitic compositions and bear sub-alkaline tholeiitic nature. Three geochemically distinct groups of mafic dykes have been identified. Group 1 samples show flat REE patterns (LaN/LuN = ~1), whereas the other two groups have LaN/LuN = ~2-3 (Group 2; enriched LREE and flat HREE patterns) and LaN/LuN = ~4 (Group 3; inclined REE patterns). Chemistry is not straightforward to support any significant role of crustal contamination and probably reflect their source characteristics. However, their derivation from melts originated from a previously modified metasomatized lithospheric mantle due to some ancient subduction event cannot be ignored. Most likely different mantle melts were responsible for derivation of these distinct sets of mafic dykes. The Group 2 dykes are derived from a melt generated within spinel stability field by ~10% batch melting of a lithospheric mantle source, whereas the Group 3 dykes have their derivation from a melt originated within the spinel-garnet transition zone and were fed from slightly higher (~12-15%) batch melting of a similar source. The Group 1 samples were also crystallized from a melt generated at the transition zone of spinel-garnet stability field by higher degrees (~20%) of melting of a primitive mantle source. Geochemistry of the studied samples is typical of Palaeoproterozoic mafic dykes emplaced within the intracratonic setting, reported elsewhere globally as well as neighbouring cratons. Geochemistry of the studied mafic dyke samples is also compared with the mafic dykes of the eastern Dharwar Craton (EDC). Except the Group 3 samples, which have good correlation with the 1.88-1.89 Ga Hampi swarm, no other group shows similarity with the EDC mafic dykes. There is an ample possibility to have some different mafic magmatic events in the WDC, which could be different from the EDC. However, it can only be confirmed after precise age determinations.
DS201412-0719
2013
Rai, S.BorahRai, S.Borah, Kajaljyoti, Das, Gupta, R., Srivastava, S., Shalivahan, P., Sivaram, K., Kumar, K., Meena, S.The South India Precambrian crust and shallow lithospheric mantle: initial results from the India Deep Imaging Experiment ( INDEX).Journal of Earth System Science, Vol. 122, 6, pp. 1435-1453.IndiaDrilling
DS201801-0041
2017
Rai, S.D.Nanda. L.K., Verma, M.B., Purohit, R.K., Khandelwal, M.K., Rai, S.D., Mundra, K.L.LREE and Nb multi metal potentiality of the Amba Dongar carbonatite complex, Chhota Udepur district, Gujarat.Carbonatite-alkaline rocks and associated mineral deposits , Dec. 8-11, abstract p. 43-44.Indiadeposit - Amba Dongar

Abstract: Rare earth elements (REE) are used in science innovations, due to their unique magnetic, fluorescent and chemical properties. REE are key components in rnany technological devices, like hybrid rechargeable batteries, catalysts, glass polishing, magnets, lasers, TV colour components, superconductors, ceramics etc. They are in great demand for hybrid cars, CD, cameras and high end defence systems. Similarly, niobium (Nb) finds its usage in diverse high tech applications including atomic energy. With increasing technological applications of REE and Nb, their global demand has enhanced over the years. To keep pace with the current demand, many carbonatite complexes in India including the Amba Dongar were revisited to assess their REE and Nb content. Amba Dongar is a classic carbonatite-alkalic rock complex of the Deccan basalt plateau and is emplaced in close proximity to Narmada rift zone. The main rock types of carbonatite affinity include sovite (calcium carbonatite), ankerite (Fe-Mg•Mn carbonatite), siderite (Fe carbonatite), carbonatite breccia (mixed rock. fragments with carbonate cement) etc. Sovite forms a large ring-dyke (nearly 1.5 km dia.) surrounding an incomplete ring of carbonatite breccia. Plugs of ankeritic carbonatite intrude the sovite. To assess rare metal and REE potential of the carbonatite complex geological and radiometric surveys followed by core drilling were carried out in western part of the complex. Rocks of carbonatite affinity have been intercepted in all the boreholes upto a maximum drilled depth of 150 m. It is for the first time that presence of carbonatite and carbonatite breccia has been reported below central basalt in the Amba Dongar complex. Continuity of carbonatites beyond the drilled depth is inferred. Petromineralogical and X-Ray Diffraction studies indicated presence of REE minerals such as monazite, thorite, cerite, synchisite and bastnasite. Besides, rare earth fluorocarbonates, parisite, florencite, barite, strontianite and columbite have also been reported by earlier investigators. Fairly good amount of pyrochlore (Nb mineral) is also present in all the variants of carbonatite. Detailed chemical analysis core at 1 m interval and of composite samples from every borehole was carried out. The results indicate homogeneity of mineralisation in the entire column upto an explored vertical depth of 120 m. Except a few lean zones, the entire column hosts REE mineralisation of the order of >1% SREE. Some zones have indicated REE mineralisation of the order of >4 % also. Major element analysis of a composite sample representing a small block (400 m x 100 m x 113 m) indicates 14.69% SiO2, 10.57% Fe2O3, 7 21% MgO, 32.23% CaO, 2.77%, Al2O3, 1.48% P2O5, 2.13% MnO, 0.84% FeO, 0.37% TiO2, 0.95% Na2O, 1.35% K2O, and 23.50% LOI. 1.16% LREE (including 161 ppm HREE), 215 ppm Y, 650 ppm Nb, 310 ppm Th and 467 ppm V appear to be of economic significance. Additionally, presence of high content of Ba (2.65%), Sr (0.50%), Pb (530 ppm), F (1.95%) and Zn (1248 ppm) is also important. Taking into consideration these results, resource estimation of a small block of 400 m x 100 m (0.04 sq. km) with an average depth of 113 m was carried out Inferred REE resources ~140000 tonnes contained in 12.00 million tonne ore have been estimated with an average grade of 1.16% REE. Additionally, this block contains 9,600 tonnes Nb2O5 at an average grade of 0 08 % Nb2O5. These values indicate high potential of Amba Dongar carbonatite complex.
DS2000-0388
2000
Rai, S.K.Hari, K.R., Kumar, M.S., Santosh, M., Rai, S.K.Melt inclusions in olivine and pyroxene phenocrysts from lamprophyres of Chhaktalao area.Journal of Asian Earth Science, Vol. 18, No.2, Apr. pp. 155-61.India, Madhya PradeshLamprophyres
DS1985-0553
1985
Rai, S.S.Rai, S.S.Crone pulse electromagnetic response of a conductive thinhorizontalsheet; theory and field applicationGeophysics, Vol. 50, No. 8, pp. 1350-1354India, Andhra PradeshWajakarur, Geophysics
DS1986-0660
1986
Rai, S.S.Rai, S.S., Bhattacharya, B.B.Quantitative interpretation of pulse electromagnetic measurements over a weathered kimberlite diatremeGeophysical Prospecting, Vol. 34, pp. 220-231IndiaGeophysics
DS1989-1442
1989
Rai, S.S.Sringesh, D., Rai, S.S., Ramesh, D.S., Gaur, V.K., Rao, C.V.R.Evidence for thick continental roots beneath South Indian shieldGeophysical Research Letters, Vol. 16, No. 9, September pp. 1055-1058IndiaMantle
DS2003-0522
2003
Rai, S.S.Gupta, S., Rai, S.S., Prakasam, K.S., Srinagesh, D., Basal, B.K., Chadha, R.K.The nature of the crust in southern India: implications for Precambrian crustal evolutionGeophysical Research Letters, Vol. 30, 8, 10.1029/2002GLO16770IndiaTectonics
DS2003-0523
2003
Rai, S.S.Gupta, S., Rai, S.S., Prakasam, K.S., Sringesh, D., Chadha, R.K., Priestly, K.First evidence for anomalous thick crust beneath mid Archean western Dharwar cratonCurrent Science, Vol. 84, 9, pp. 1219-26.IndiaCraton
DS2003-1100
2003
Rai, S.S.Prakasam, K.S., Rai, S.S.Crustal thickening and composition in eastern Dharwar CratonMemoirs Geological Society of India, Vol. 53, pp. 115-128. Ingenta 1035483299IndiaBlank
DS200412-0750
2003
Rai, S.S.Gupta, S., Rai, S.S., Prakasam, K.S., Srinagesh, D., Basal, B.K., Chadha, R.K., Priestly, K., Gaur, V.K.The nature of the crust in southern India: implications for Precambrian crustal evolution.Geophysical Research Letters, Vol. 30, 8, 10.1029/2002 GLO16770IndiaTectonics
DS200412-0751
2003
Rai, S.S.Gupta, S., Rai, S.S., Prakasam, K.S., Sringesh, D., Chadha, R.K., Priestly, K., Gaur, V.K.First evidence for anomalous thick crust beneath mid Archean western Dharwar craton.Current Science, Vol. 84, 9, pp. 1219-26.IndiaCraton
DS200412-1576
2003
Rai, S.S.Prakasam, K.S., Rai, S.S.Crustal thickening and composition in eastern Dharwar Craton.Memoirs Geological Society of India, Vol. 53, pp. 115-128. Ingenta 1035483299IndiaGeochemistry
DS200812-0573
2008
Rai, S.S.Kiselev, S., Vinnik, L., Oreshin, S., Gupta, S., Rai, S.S., Singh, A., Kumar, Mohan.Lithosphere of the Dharwar craton by joint inversion of P and S receiver functions.Geophysical Journal International, In press ( available)IndiaGeophysics - seismics
DS200912-0292
2009
Rai, S.S.Heintz, M., Kumar, V.P., Gaur, V.K., Priestly, K., Rai, S.S., Prakasam, K.S.Anisotropy of the Indian continental lithospheric mantle.Geophysical Journal International, Vol. 179, 3, pp. 1341-1360.IndiaGeodynamics
DS200912-0609
2009
Rai, S.S.Rai, A., Gaur, V.K., Rai, S.S., Preistley, K.Seismic signatures of the Pan-African orogeny: implications for southern Indian high grade terranes.Geophysical Journal International, Vol. 176, 2, pp. 518-528.IndiaUHP
DS201112-0762
2011
Rai, S.S.Oreshin, S.I., Vinnik, L.P., Kiselev, S.G., Rai, S.S., Prakasam, K.S., Treussov, A.V.Deep seismic structure of the Indian shield, western Himalaya, Ladakh, and Tibet.Earth and Planetary Science Letters, Vol. 307, 3-4, pp. 415-429.IndiaSubduction
DS201312-0571
2012
Rai, S.S.Mandal, N., Charavarty, K.H., Borah, K., Rai, S.S.Is a cation ordering transition of the Mg-Fe olivine phase in the mantle responsible for the shallow mantle seismic discontinuity beneath the Indian craton?Journal of Geophysical Research, 9225IndiaHales discontinuity
DS201510-1764
2015
Rai, S.S.Das, R., Saikia, U., Rai, S.S.The deep geology of South India inferred from Moho depth and Vp/Vs ratio.Geophysical Journal International, Vol. 203, pp. 910-926.IndiaGeophysics - seismics

Abstract: We present a comprehensive study of thickness and composition of the crust; and the nature of crust-mantle boundary beneath Southern India using P-wave receiver function from 119 seismic stations. Data from distributed network of seismograph location encompass geological domains like mid to late Archean Dharwar craton, Archean and Proterozoic metamorphic terrains, Proterozoic basin, rifted margins and escarpments, and Deccan volcanics. Except for the mid to lower crust exhumed Archean terrains (of West Dharwar and Southern Granulite) all other geological domains have crustal thickness in the range 33-40 km. In the western Dharwar, crustal thickness increases from ~40 km in the north to over 50 km in the south. The Archean domain of granulite terrain is thicker (40-45 km) and more mafic compared to its counterpart in south deformed at 550 Ma. Most of the crustal blocks have low to moderate Vp/Vs (1.72-1.76) representing a felsic to intermediate composition. Exception to the above include Archean granulite terrain with high Vp/Vs (1.76–1.81) suggestive of more mafic crust beneath them. When accounted for the paleo burial depth of 15-25 km, the study suggests a possible Himalaya-Tibet like scenario beneath the mid-late Archean in southwestern Dharwar and north granulite terrain whose deeper crust has progressively densified. This led to a gradational crust-mantle transition that is otherwise sharp elsewhere. The study suggests a more homogenized and felsic nature of the Precambrian crust beneath the terrains formed after 2.6 Ga, possibly due to delamination of the mafic lower crust. Our study does not suggest any distinction between late Archean and Proterozoic crust. The Deccan volcanism at 65 Ma does not appear to have altered the crustal character beneath it and is similar to the adjoining late Archean east Dharwar craton. The western Ghat escarpment and the coastal plain formed due to separation of India from Madagascar are underlain by mafic lower crust.
DS201904-0776
2019
Rai, S.S.Saikia, U., Jumar, V.P., Rai, S.S.Complex upper mantle deformation beneath the Dharwar craton inferred from high density splitting measurements: distinct lateral variation from west to east.Tectonophysics, Vol. 755, pp. 10-20.Indiageophysics - seismics

Abstract: Upper mantle anisotropy investigated using 172 core-refracted (SKS, SKKS) seismic phases along a ~660?km long profile at 10 to 20?km intervals from the west to the east coast of South India reveals significant lateral variations in its magnitude and direction. This profile, with 38 broadband seismic stations, covers mid-Archean Western Dharwar craton (WDC), late-Archean Eastern Dharwar Craton (EDC), Proterozoic Cuddapah Basin (CB) and the passive continental margins along the west and east coast. The observed fast polarization directions (FPDs) show lateral variability: NW50o to NW5o beneath the WDC, NW40o to NE30o beneath the EDC and N5o to N85o beneath the CB and further east. The delay time varies between 0.4 and 2.0?s with an average of 1?s. However, we are unable to fit a two layers anisotropy model for the region due to sparse azimuth coverage. Beneath the WDC, the direction of the fast axis follows trends of shear zones and faults, suggesting “frozen-in” anisotropy in the lithosphere, possibly established during the lithospheric evolution in mid-late Archean. In the EDC, the fast axis does not only follow the plate motion direction but it deviates, manifesting late Archean to Proterozoic deformation may still be present as fossil mantle anisotropy. The splitting trend beneath the CB and Eastern Ghat (EG) follows the strike of the rift along with plate motion direction, indicating anisotropy is influenced by the combination of “frozen” anisotropy due to continental rifting along the eastern margin of Indian plate and active asthenospheric flow.
DS201112-0440
2011
Rai, V.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
DS201312-0736
2013
Rai, V.K.Ray, J.S., Pnde, K., Bhutani, R., Shukla, A.D., Rai, V.K., Kumar, A., Awasthi, N., Smitha, R.S., Panda, D.K.Age and geochemistry of the Newania dolomite carbonatites, India: implications for the source of primary carbonatite magma.Contributions to Mineralogy and Petrology, Vol. 166, 6, pp. 1613-1632.IndiaCarbonatite
DS2001-0958
2001
Raiche, A.Raiche, A.Choosing an AEM system to look for kimberlites - a modelling studyExploration Geophysics, (ASEG Bulletin.), Vol. 32, No. 1, March pp. 1-8.GlobalGeophysics - TEM, AEM, HEM., Methodology - techniques
DS200512-0485
2005
Raimbourg, H.Jolivet, L., Raimbourg, H., Labrousse, L., Avigad, D., Leroy, Y., Austrheim, H., Andersen, T.B.Softening triggered by eclogitization, the first step toward exhumation during continental subduction.Earth and Planetary Science Letters, Vol. 237, 3-4, Sept. 15, pp. 532-547.Europe, NorwayEclogite, subduction
DS200712-0865
2006
Raimbourg, H.Raimbourg, H., Jolivet, L., Leroy, Y.Consequences of progressive eclogization on crustal exhumation, a mechanical study.Geophysical Journal International, Vol. 168, 1, pp. 379-401.TechnologyEclogite
DS200812-0931
2008
Raimbourg, H.Raimbourg, H., Kimura, G.Non-lithostatic pressure in subduction zones.Earth and Planetary Science Letters, Vol. 274, pp. 414-422.MantleSubduction
DS201312-0012
2013
Raimondo, T.Aitken, A.R.A., Raimondo, T., Capitano, F.A.The intraplate character of supercontinent tectonics.Gondwana Research, Vol. 24, 3-4, pp. 807-814.AfricaGeodynamics
DS201412-0720
2013
Raimondo, T.Raimondo, T., Hand, M., Collins, W.J.Compressional intracontinental orogens: ancient and modern perspectives.Earth Science Reviews, Vol. 130, pp. 128-153.MantleGeodynamics
DS200512-0834
2005
Rainbird, R.Pehrsson, S.L., Berman, R.G., Rainbird, R., Davis, W., Skulski, Sanborn-Barrie, Van Breeman, Corrigan, TellaInterior collisional orogenesis related to supercontinent assembly: the ca. 1.9- 1.5 Ga tectonic history of the western Churchill province.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, SaskatchewanNuna, tectonics
DS201312-0694
2013
Rainbird, R.Pehrsson, S.J., Berman, R.G., Eglinton, B., Rainbird, R.Two Neoarchean supercontinents revisited: the case for a Rae family of cratons.Precambrian Research, Vol. 232, pp. 27-43.Canada, SaskatchewanKenoraland revised, Nunavutia
DS1990-1178
1990
Rainbird, R.H.Peterson, T.D., Rainbird, R.H.Tectonic and petrological significance of regional lamproite-minette volcanism in the The lon and Trans-Hudson hinterlands, Northwest TerritoriesGeol. Suv. of Canada Current Research Part C., Canadian Shield, Paper No. 90-1C, pp. 69-80Northwest TerritoriesLamproite-minette, Tectonics/petrology
DS1992-0689
1992
Rainbird, R.H.Heaman, L.M., LeCheminant, A.N., Rainbird, R.H.Nature and timing of Franklin igneous events, Canada: implications for a Late Proterozoic mantle plume and the break-up of LaurentiaEarth and Planetary Science Letters, Vol. 109, No. 1-2, March pp. 117-132GlobalMantle, Proterozoic
DS1992-1248
1992
Rainbird, R.H.Rainbird, R.H., Heaman, L.M., Young, G.Sampling Laurentia: detrital zircon geochronology offers evidence for an extensive Neoproterozoic river system originating from the Grenville orogenGeology, Vol. 20, No. 4, April pp. 351-354Victoria IslandShaler Group, Geochronology
DS1993-1276
1993
Rainbird, R.H.Rainbird, R.H.The sedimentary record of mantle plume uplift preceding eruption of the Neoporterozoic Natkusiak flood basalt.Journal of Geology, Vol. 101, pp. 305-18.Northwest Territories, Victoria IslandTectonics
DS1997-0942
1997
Rainbird, R.H.Rainbird, R.H., De Freitas, E.A.Stratigraphic evidence for the Siberia Laurentia connection and early Cambrian rifting: comments/reply.Geology, Vol. 25, No. 6, June pp. 569-572.Russia, Siberia, Anabar shield, Baffin Island, Victoria IslandStratigraphy, Rifting
DS1998-1203
1998
Rainbird, R.H.Rainbird, R.H., Stern R.A., Sukhorukov, V.I.uranium-lead (U-Pb) geochronology of Riphean sandstone and gabbro from southeast Siberia and its bearing on Laurentia-SiberiaEarth and Planetary Science Letters, Vol.164, No.3-4, Dec.30, pp.409-20.Russia, Siberia, LaurentiaGeochronology, Not specific to diamonds
DS2001-0959
2001
Rainbird, R.H.Rainbird, R.H., Ernst, R.E.The sedimentary record of mantle plume upliftGeological Society of America, Special Paper, Special Paper. 352, pp. 227-46.MantleRifting, tectonics, Plumes
DS2003-1123
2003
Rainbird, R.H.Rainbird, R.H., Hadlari, T., Aspler, L.B., Donaldson, J.A., Le Cheminant, A.N.Sequence stratigraphy and evolution of the Paleoproterozoic intracontinental BakerPrecambrian Research, Vol. 125, 1-2, pp. 21-53.NunavutBlank
DS200412-0782
2004
Rainbird, R.H.Hanmer, S., Sandeman, H.A., Davis, W.J., Aspler, L.B., Rainbird, R.H., Ryan, J.J., Relf, C., Peterson, T.D.Geology and Neoarchean tectonic setting of the Central Hearne supracrustal belt, Western Churchill Province, Nunavut, Canada.Precambrian Research, Vol. 134, 1-2, pp. 63-83.Canada, NunavutTectonics - not specific to diamonds
DS200412-1609
2003
Rainbird, R.H.Rainbird, R.H., Hadlari, T., Aspler, L.B., Donaldson, J.A., Le Cheminant, A.N., Peterson, T.D.Sequence stratigraphy and evolution of the Paleoproterozoic intracontinental Baker Lake and The lon Basins, western Churchill ProPrecambrian Research, Vol. 125, 1-2, pp. 21-53.Canada, NunavutGeology
DS1860-0952
1896
Rainconi, F.Rainconi, F.Cartes Commerciales et Minieres des Pays Sud-africainsParis:, 114P.Africa, South AfricaDiamond mining
DS201212-0576
2012
Rainer, t.Rainer, t., Davidson, P.The application of Raman spectroscopy in the study of fluid and melt inclusions.Zeitschrift der Deutschen Gesellschaft fur Geowissenschaften, Vol. 163, 2, pp. 113-126.TechnologyGraphite, diamond
DS1984-0486
1984
Raines, G.L.Marrs, R.W., Raines, G.L.Tectonic Framework of Powder River Basin, Wyoming and Montana Interpreted from Land sat Imagery.American Association Petrol. Geol., Vol. 68, No. 11, NOVEMBER PP. 1718-1731.United States, Montana, Wyoming, Rocky MountainsTectonics, Remote Sensing, Lineaments, Sedimentation
DS2002-1300
2002
Raines, G.L.Raines, G.L.Description and comparison of geologic maps with FRAGSTATS - a spatial statistics program.Computers and Geosciences, Vol.28, 2, pp. 169-77.GlobalComputer - FRAGSTATS
DS200512-1115
2005
Rainey, E.S.Van den Berg, A.P., Rainey, E.S., Yuen, D.A.The combined influence of variable thermal conductivity, temperature and pressure dependent viscosity and core mantle coupling on thermal evolutionPhysics of the Earth and Planetary Interiors, Vol. 149, 3-4, pp. 259-278.MantleGeothermometry
DS201412-0911
2014
Rainey, E.S.Tang, X., Ntam, M.C., Dong, J., Rainey, E.S., Kavner, A.The thermal conductivity of Earth's lower mantle.Geophysical Research Letters, Vol. 41, 8, pp. 2746-2752.MantleGeothermometry
DS200512-1116
2005
Rainey, E.S.G.Van den Berg, A.P., Rainey, E.S.G., Yuen, D.A.Dependent viscosity and core mantle coupling on thermal evolution.Physics of the Earth and Planetary Interiors, Vol. 149, 3-4, April 15, pp. 259-278.MantleGeothermometry
DS201112-0839
2011
Rainey, E.S.G.Rainey, E.S.G., Kavner, A., Hernlund, J.Heat flow in the laser heated diamond anvil cell and the thermal conductivity of the lower mantle.Goldschmidt Conference 2011, abstract p.1689.Mantle3D
DS201412-0912
2014
Rainey, E.S.G.Tang, X., Ntam, M.C., Dong, J., Rainey, E.S.G., Kavner, A.The thermal conductivity of Earth's lower mantle.Geophysical Research Letters, Apr. 16 DOI: 10.1002/2014 GL059385MantleGeothermometry
DS201412-0913
2014
Rainey, E.S.G.Tang, X., Ntam, M.C., Dong, J., Rainey, E.S.G., Kavner, A.The thermal conductivity of Earth's lower mantle.Geophysical Research Letters, April 16, pp. 2746-2742.MantleGeothermometry
DS201412-0914
2014
Rainey, E.S.G.Tang, X., Ntam, M.C., Dong, J., Rainey, E.S.G., Kavner, A.The thermal conductivity of Earth's lower mantle.Geophysical Research Letters, Vol. 41, 8, pp. 2746-2752.MantleGeothermometry
DS1993-1277
1993
Rains, B.Rains, B., Shaw, J., Skoye, R., Sjogren, D., Kvill, D.Late Wisconsin subglacial megaflood paths in AlbertaGeology, Vol. 21, No. 4, April pp. 323-326.AlbertaGeomorphology, Glacial
DS2003-1339
2003
Rainsford, D.Stott, G., Rainsford, D.Interpreting the Precambrian under the Lowlands: implications for mineral explorationOntario Exploration and Geoscience Symposium, Dec. 8,9,10th., Abstracts p. 2. (1/8p.)Ontario, AttawapiskatMapping
DS200412-1933
2003
Rainsford, D.Stott, G., Rainsford, D.Interpreting the Precambrian under the Lowlands: implications for mineral exploration. GIS database - two maps 1:500,000Ontario Exploration and Geoscience Symposium, Dec. 8,9,10th., Abstracts p. 2. (1/8p.)Canada, Ontario, Attawapiskat, James Bay LowlandsMapping
DS1993-0478
1993
Rainville, J.Gagnon, G-Y., Rainville, J.A kimberlite discovery in the Temiscaminque areaQuebec Exploration Conference summaries held September 15-1th. Val d'Or, pp. 10-12QuebecTemiskaming area
DS1995-1538
1995
Raisanen, M.L.Raisanen, M.L., Tarvainen, T., Aaros, S.NORMA - a program to calculate a normative mineralogy for glacial tills and rocks from chemical analysis.Gff., Vol. 117, pp. 215-224.GlobalGeomorphology, Computer Program - NORMA.
DS1990-1156
1990
Raiser, S.Park, A.F., Raiser, S.Geology of the south western part of Tavani map area, 55 K 3, 4, 5, 6, District of Keewatin, northwest Territories.Geological Survey of Canada (GSC) Open File, No. 2265, 103p.Northwest TerritoriesGeology
DS1860-0692
1891
Raisin, C.A.Bonney, T.G., Raisin, C.A.Report on Some Rock Specimens from the Kimberley Diamond MinGeology Magazine , Dec. 3, Vol. 7, PP. 412-415.Africa, South Africa, Griqualand WestDiamond mines, mineralogy, petrology
DS1860-0883
1895
Raisin, C.A.Bonney, T.G., Raisin, C.A.Notes on the Diamond Bearing Rock of Kimberley, South Africa. the Kimberley Diamond Mines.Geology Magazine , Dec. 4, Vol. 2, PP. 496-502. Neues Jahrbuch fnr Mineralogie BD. 2, PP. 43Africa, South Africa, Cape ProvinceDiamond mines, mineralogy, petrology
DS1900-0310
1905
Raisin, C.A.Bonney, T.G., Raisin, C.A.The Microscopic Structure of Minerals Forming Serpentine And Their Relation to its History.Quarterly Journal of Geological Society, Vol. 61, PP. 690-714. ALSO. Proceedings Geological Society 1904-1905, P. 1Africa, South AfricaRelated Rocks
DS201808-1770
2018
Raisson, S.Mourot, Y., Roddaz, M., Dera, G., Calves, G., Kim, J-H., Charboureau, A-C., Mounic, S., Raisson, S.Geochemical evidence for large scale drainage reorganization in northwest Africa during the Cretaceous.Geochemistry, Geophysics, Geosystems, Vol. 19, 5, pp. 1690-1712.Africageomorphology

Abstract: West African drainage reorganization during Cretaceous opening of the Atlantic Ocean is deciphered here from geochemical provenance studies of Central Atlantic sediments. Changes in the geochemical signature of marine sediments are reflected in major and trace element concentrations and strontium-neodymium radiogenic isotopic compositions of Cretaceous sedimentary rocks from eight Deep Sea Drilling Project (DSDP) sites and one exploration well. Homogeneous major and trace element compositions over time indicate sources with average upper (continental) crust signatures. However, detailed information on the ages of these sources is revealed by neodymium isotopes (expressed as ?Nd). The ?Nd(0) values from the DSDP sites show a three-step decrease during the Late Cretaceous: (1) the Albian-Middle Cenomanian ?Nd(0) values are heterogeneous (-5.5 to -14.9) reflecting the existence of at least three subdrainage basins with distinct sedimentary sources (Hercynian/Paleozoic, Precambrian, and mixed Precambrian/Paleozoic); (2) during the Late Cenomanian-Turonian interval, ?Nd(0) values become homogeneous in the deepwater basin (-10.3 to -12.4), showing a negative shift of 2 epsilon units interpreted as an increasing contribution of Precambrian inputs; (3) this negative shift continues in the Campanian-Maastrichtian (?Nd(0)?=?-15), indicating that Precambrian sources became dominant. These provenance changes are hypothesized to be related to the opening of the South and Equatorial Atlantic Ocean, coincident with tectonic uplift of the continental margin triggered by Africa-Europe convergence. Finally, the difference between ?Nd(0)values of Cretaceous sediments from the Senegal continental shelf and from the deepwater basins suggests that ocean currents prevented detrital material from the Mauritanides reaching deepwater areas.
DS1994-1384
1994
Raiswell, R.W.Plant, J.A., Raiswell, R.W.Mentions of diamond on p. 107, 190, 192, 202, 208, 224 in DrainageGeochemistry.Handbook of Exploration Geochemistry, Vol. 6, excerptsGlobalGeochemistry, Diamonds
DS200612-1094
2006
Raita, T.SSTWG.Plomerova, J., Babuska, V., Vecsey, L., Kozlovskaya, E., Raita, T.SSTWG.Proterozoic Archean boundary in the mantle lithosphere of eastern Fennoscandia as seen by seismic anisotropy.Journal of Geodynamics, Vol. 41, 4, May pp. 400-410.Europe, FennoscandiaGeophysics - seismics
DS1999-0773
1999
Raitala, J.Vishnevskii, S.A., Palchik, N.A., Raitala, J.Diamonds in impactites of the Lappajarvi impact craterRussian Geology and Geophysics, Vol. 40, No. 10, pp. 1487-90.FinlandImpact crater
DS2003-1124
2003
Raith, J.G.Raith, J.G., Cornell, D.H., Frimmel, H.E., De Beer, C.H.New insights into the geology of the Namaqua tectonic province, South Africa, from ionJournal of Geology, Vol. 111, 3, pp. 347-66.South AfricaTectonic - zone, Geochronology
DS200412-1610
2003
Raith, J.G.Raith, J.G., Cornell, D.H., Frimmel, H.E., De Beer, C.H.New insights into the geology of the Namaqua tectonic province, South Africa, from ion probe dating of detrital and metamorphicJournal of Geology, Vol. 111, 3, pp. 347-66.Africa, South AfricaTectonic - zone Geochronology
DS2001-0977
2001
Raith, M.M.Rickers, K., Mezger, K., Raith, M.M.Evolution of the continental crust in the Proterozoic eastern Gnats belt, new constraints for Rodinia reconstPrecambrian Research, Vol. 112, No. 3-4, Dec. 10, pp. 183-210.IndiaGeochronology - Sm neodymium Rb Sr lead lead, Gondwana
DS200612-1450
2006
Raith, M.M.Upadhyay, D., Raith, M.M.Petrogenesis of the Kunavaram alkaline complex and the tectonothermal evolution of the neighbouring Eastern Ghats Belt granulites SE India.Precambrian Research, in press - availableIndiaAlkaline rocks, geochemistry, geochronology
DS200612-1451
2006
Raith, M.M.Upadhyay, D., Raith, M.M., Mezger, K., Bhattacharya, A., Kinny, P.D.Mesoproterozoic rifting and Pan African continental collision in SE India: evidence from the Khariar alkaline complex.Contributions to Mineralogy and Petrology, Vol. 141, 4, April pp. 434-456.Asia, IndiaTectonics
DS200612-1452
2006
Raith, M.M.Upadhyay, D., Raith, M.M., Mezger, K., Hammerschmidt, K.Mesoproterozoic rift related alkaline magmatism at Elchuru, Prakasam alkaline province, SE India.Lithos, Vol. 89, 3-4, July pp. 447-477.IndiaBasanites, Tectonics, magmatism, Eastern Gnats Belt
DS200412-1611
2004
Raj, K.G.Raj, K.G., Nijajunappa, R.Major lineaments of Karnataka State and their relations to seismicity: a remote sensing based analysis.Journal Geological Society of India, Vol. 63, 4, pp. 430-439.IndiaTectonics, geophysics - seismics
DS2002-0010
2002
Rajagopalan, G.Agarwal, K.K., Singh, I.B., Sharma, M., Sharma, S., Rajagopalan, G.Extensional tectonic activity in the cratonward parts ( peripheral bulge) of the Ganga Plain foreland basin, India.International Journal of Earth Sciences, Vol. 91, 5, pp. 897-905.IndiaTectonics - not specific to diamonds
DS1989-0559
1989
Rajakuma.., V.Gupta, S.K., Rajakuma.., V., Grieveso..P.The influence of weathering on the reduction of ilmenite with carbonMetall. T-B., Vol. 20, No. 5, October pp. 735-745. AX896GlobalIlmenite -general, Weathering
DS1990-1210
1990
Rajamani, K.Rajamani, K., Herbst, J.A.Control '90-mineral and metallurgical processingAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Book, 600p. approx. $ 70.00GlobalMineral processing, Control 90 - from meeting presentations
DS1993-1278
1993
Rajamani, V.Rajamani, V., Balakrishnan, S., Hanson, G.N.Komatiite genesis: insights provided by iron-magnesium exchange equilibriaJournal of Geology, Vol. 101, No. 6, November pp. 809-819IndiaKomatiite, Archean, Kolar Schist Belt, Genesis
DS1999-0041
1999
Rajamani, V.Balakrishnan, S., Rajamani, V., Hanson, G.N.uranium-lead (U-Pb) ages for zircon and titanite from the Ramagiri area, evidence for accretionary origin ....Late ArcheanJournal of Geology, Vol. 107, No.1, Jan. pp. 69-86.India, South IndiaGeochronology, Dharwar Craton
DS201112-0170
2011
Rajamanickam, G.V.Chandrasekar, N., Sheik Mujabar, P., Rajamanickam, G.V.Investigation of heavy mineral deposits using multispectral satellite data.Journal of the Geological Society, Vol. 168, 8, pp. 8641-8655.TechnologyHyperspectral
DS1975-1191
1979
Rajamaran, S.Rajamaran, S., et al.Stream Sediment Surveys in Kelyandurg Area, Anantapur District for Locating Kimberlite Pipes.India Geological Survey Program Report, FOR 1978-1979India, Andhra PradeshDiamond Prospecting, Geochemistry
DS202009-1627
2020
Rajan, S.Fareeduddin, Pant, N.C., Gupta, S., Chakraborty, P., Sensarma, S., Jain, A.K., Prasad, G.V.R., Srivastava, P., Rajan, S., Tiwari, V.M.The geodynamic evolution of the Indian subcontinent - an introduction.Episodes, Vol. 43, 1, pp. 8p.Indiacarbonatites
DS2000-0389
2000
Rajaram, M.Harikumar, P., Rajaram, M., Balakrishnan, T.S.Aeromagnetic study of peninsular IndiaProceedings Indian Academy of Science, Vol. 109, No. 3, Sept pp. 381-91.IndiaGeophysics - magnetics
DS2002-0032
2002
Rajaram, M.Anand, S.P., Rajaram, M.Aeromagnetic dat a to probe the Dharwar CratonCurrent Science, Vol.83,2,Julyy 25, p. 162-66.IndiaGeophysics - magnetics, Craton
DS200412-0031
2003
Rajaram, M.Anand, S.P., Rajaram, M.Crustal perspective of Narmada-Son lineament: an aeromagnetic perspective.Earth Planets and Space, Vol. 56, 5, pp. e9-e12. IngentaIndiaGeophysics - magnetics
DS200412-1612
2003
Rajaram, M.Rajaram, M., Anand, S.P.Central Indian tectonics revisited using aeromagnetic data.Earth Planets and Space, Vol. 55, 12, pp. e1-e4. Ingenta 1035538701IndiaGeophysics - magnetics, Namada Son lineament , dyke swa
DS200912-0610
2009
Rajaram, M.Rajaram, M., Anand, S.P., Hermant, K., Purucker, M.E.Currie isotherm map of Indian subcontinent from satellite and aeromagnetic data.Earth and Planetary Science Letters, Vol. 281, 3-4, May 15, pp. 147-158.IndiaGeophysics - magnetics
DS201312-0730
2013
Rajaram, M.Rajaram, M., Anand, S.P.Aeromagnetic signatures of Precambrian shield and suture zones of Peninsular India.Geoscience Frontiers, in press availableIndiaGeophysics
DS1992-1249
1992
Rajaram, V.Rajaram, V.Changing roles of the geologist and engineer...(communication)The Professional Geologist, August pp. 10GlobalProfessional registration, Comments
DS1960-1195
1969
Rajaraman, S.Rajaraman, S., Deshpande, M.L.Report on the Preliminary Investigation for Diamonds in The banganapalle Conglomerate and Tungabhadra Krishna River Gravels in Parts of Kurnool and Mahaboolonagar Districts.India Geological Survey Program Report, FOR 1967-1968India, Andhra PradeshDiamond Prospecting
DS1970-0372
1971
Rajaraman, S.Narayanaswami, S., Hunday, A., Rajaraman, S., Deshpande, M.L.The Current Exploration for Diamond in Different Host Rocks of Andhra Pradesh by the Geological Survey of India.India Geological Survey Miscellaneous Publishing, No. 19, PP. 42-48.IndiaProspecting
DS1970-0809
1973
Rajaraman, S.Rajaraman, S., Rao, A.V.K.Report on the Investigation for Diamond Carries Out in Pipe-1 in Wajrakarur, Anantapur District, Andhra Pradesh.India Geological Survey Program Report, FOR 1968-1973India, Andhra PradeshDiamond Prospecting
DS1975-0844
1978
Rajaraman, S.Rajaraman, S., Deshpande, M.L.Banganapalle Diamondiferous Conglomerates in Kurnool District, A.p.Indian Minerals, Vol. 32, No. 3, PP. 33-43.India, Andhra PradeshGeology
DS1975-0845
1978
Rajaraman, S.Rajaraman, S., Deshpande, M.L.Status of Assessment of Diamond Resources in Andhra PradeshIndian Minerals, Vol. 32, No. 2, PP. 39-45.India, Andhra PradeshMineral Resources
DS1975-1192
1979
Rajaraman, S.Rajaraman, S.A Short Note on the William son Diamond Mines, Mwadui, Shinyanga Region, Tanzania.Indian Minerals, Vol. 33, No. 1, P. 52.Tanzania, East AfricaHistory
DS1980-0283
1980
Rajaraman, S.Rajaraman, S., et al.Diamond Deposits of Transported Origin in Andhra PradeshTranscript of Paper From Diamond Seminar, Bombay, 11P.India, Andhra PradeshDiamond Occurrences
DS1975-1193
1979
Rajarman, S.Rajarman, S.A Short Note on the William son Diamond Mine, Mwadui, Shinyanga Region, Tanzania.Indian Minerals, Vol. 33, No. 1, P. 52.Tanzania, East AfricaGeology
DS200612-0922
2006
Rajasekar, R.P.Mishra, D.C., Kumar, V.V., Rajasekar, R.P.Analysis of airborne magnetic and gravity anomalies of peninsular shield, India integrated with seismic, magnetotelluric and gravity anomalies.Gondwana Research, Vol. 10, Aug.1-2, pp. 6-17.India, Africa, MadagascarGeophysics - magnetics, gravity
DS200712-0866
2007
Rajendra Prasad, B.Rajendra Prasad, B., Kesava Rao, G., Mall, D.M., Koteswarar Rao, P., Raju, S., Reddy, SridherTectonic implications of seismic reflectivity pattern observed over the Precambrian southern granulite terrain, India.Precambrian Research, Vol. 153, 1-2, pp. 1-10.IndiaGeophysics - seismics
DS1999-0576
1999
Rajendran. K., C.P.Rajendran. K., C.P.Seismogenesis on the stable continental interiors: an appraisal based on two examples from India.Tectonophysics, Vol. 305, No. 3, May 10, pp. 355-70.IndiaGeophysics - seismics, Craton
DS200412-2185
2003
Rajesh, H.M.Yoshida, M., Jacobs, J., Santosh, M., Rajesh, H.M.Role of Pan African events in the Circum East Antarctic Orogen of East Gondwana: a critical overview.Proterozoic East Gondwana: Supercontinent assembly and Breakup. Ed. Yoshida , Geological Society of London Spe, No. 206, pp. 57-76.AntarcticaPlume, tectonics
DS200812-0436
2008
Rajesh, H.M.Gutzmer, J., Harding, C.H., Beukes, N.J., Huizenga, J.M., Rajesh, H.M.Continental rifting, alkaline magmatism and the formation of high grade iron ores along the western margin of the Kaapvaal Craton, South Africa.GSSA-SEG Meeting Held July, Johannesburg, 33 Power point slidesAfrica, South Africa, Namibia, BotswanaMagmatism
DS201212-0461
2012
Rajesh, K.Melluso, L., Rajesh,K., Srivastava, C.M., Petrone, V., Guarino, V., Sinha, A.K.Mineralogy, magmatic affnity and evolution of the Early Cretaceous alkaline complex of Jasra, Shillong Plateau, northeastern India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Jasra
DS200812-0773
2008
Rajesh, M.Mukhopadhyay, R., Rajesh, M., De, S., Chakraborty, B., Jauhan, P.Structural highs on the western continental slope of India: implications for regional tectonics.Geomorphology, Vol. 96, 1-2, pp. 48-61.IndiaTectonics
DS200412-1613
2004
Rajesh, R.S.Rajesh, R.S., Mishra, D.C.Lithospheric thickness and mechanical strength of the Indian Shield.Earth and Planetary Science Letters, Vol. 225, 3-4, pp. 319-328.IndiaTectonics
DS201801-0051
2017
Rajesh, S.Rajesh, S., Pradeepkumar, A.P.Carbonatite occurrences in Munnar area, Kerala, southern India.Carbonatite-alkaline rocks and associated mineral deposits , Dec. 8-11, abstract p. 36-37.Indiacarbonatites

Abstract: Carbonatites, usually associated with alkaline complexes and emplaced within continental rifting environment, are the rarest of all the igneous rocks. Carbonatite and alkaline intrusive complexes, as well as their weathering products, are the primary sources of REEs (Long et.al. 2010). Carbonatites are defined by the International Union of Geological Sciences (IUGS) system of igneous rock classification as having more than 50 modal percent primary carbonate minerals, such as calcite, dolomite, and ankerite, and less than 20 percent SiO2 (Le Maitre, 2002). Southern India has several carbonatite occurrences and the alkaline complex of Munnar in southern India comprises of an alkali granite plutons with minor patches of charnockite, syenite and carbonatite emplaced within Precambrian gneisses (Nair et.al., 1983, 1984; Santosh et.al., 1987, Nair et.al., 1984). Gneissic layering and foliation are apparent in all but the least deformed granitic rocks in the study area. The Munnar granite body is situated in the western part of the Madurai block in Southern Granulite Terrane (SGT) of Peninsular India, within the newly defined Western Madurai Domain. The complex is spatially related to the intersection zone of Karur-Kambam-Painavu-Trissur lineament. The alkali granite of the complex has been dated at 740±30 my (Odom, 1982) and 804±6 Ma (Brandt et. al., 2014). Present study deals with examining the nature of the carbonatites and takes a relook at its major and REE contents, and for the first time, looks at the stable isotope signatures of these rocks, in an attempt to check whether these rocks are indeed carbonatites. The geology and geochemistry of the rock types in and around Munnar area have been mapped with special focus on carbonatites. Extensive field mapping was carried out and a base map was prepared and all the geological and structural features were recorded in the base map. Intra- and inter-relationships of various rock units were examined. Field photographs of interesting geological features have been recorded. Carbonatites in Munnar area are exposed as two minor patches. The one which occurs towards north of the Munnar town and is seen as patches, lens and veins of 30 cm to 1 m thickness, cutting coarse grained syenite which occurs as a NW- SE along a body. Exposures are found about 15 km from Munnar on the Udumalpet road. The second exposure occurs towards the east of the Munnar town, near at the Ellapatty estate 24 km from Munnar on the road to top station where coarse grained cabonatites occurs as lenticular bodies up to 1.5 m thick within granite. In both the localities, the carbonatite bodies show sharp and discordant margins with absence of any pseudomorphs within them. Fenitisation is characterised by the development of pink K-feldspar megacrystals in the country rock at the contact. The carbonatites are fresh and homogenous and represent two varieties. A coarse grained holocrystalline type and yellowish calcite crystals constituting 90% of the rock, with pyroxene apatite and magnetite correspond to sovite (Streckeisen, 1979). The second variety which contains highly coarse calcite crystals (up to 1 cm) and associated dolomite with mafic minerals constituting 30% of the rock corresponds to alvikite. The sovite exhibits an interlocking crystals mosaic of calcite in thin section. The calcite crystals of alvikite show exsolution blebs of dolomite. The major mafic component in both varieties is aegirine-augite which forms euhedral- subhedral laths (Santosh et al., 1984). The opaque phase is dominantly magnetite. Rarely phlogopite, biotite and minor laths of albite are also noted, small crystals of euhedral apatite are found occluded in calcite grain although alkaline complexes with carbonatite of Munnar devoid of related mafic differentiates like gabbros or lamprophyres may be considered unique. The immiscibility of carbonatitic and alkalic silicate liquids can be physically explained as the separation of a less viscous carbonate liquid from a more viscous polymerized silicate phase. The carbonate liquid would be lower in density because of higher content of H2O and this contrast in density could cause phase separation due to earth’s gravitational field alone (Moller et al., 1980). The pre-requisite to establish separation of immiscible silicate-saturated carbonatite liquid and the associated carbonate-saturated silicate melt is achieved as follows; Large-scale volatile outgassing occurs during crustal wrapping and distention prior to rifting which trigger mantle degassing (Bailey, 1974). An imprint of such large-scale volatile influx is recognised in the Kerala region (Nair et al., 1984). Rapid ascent volatiles enriched in CO2 liberated from the mantle cause partial melting at shallower levels of the mantle.
DS202009-1630
2020
Rajesh, S.Hegner, E., Rajesh, S., Willbold, M., Muller, D., Joachimiski, M., Hofmann, M., Linnemann, U., Zieger, J., Pradeepkumar, A.P.Sediment derived origin of the putatative Munnar carbonatite, South India.Journal of Asian Earth Science, Vol. 200, 104432, 18p. PdfIndiadeposit - Munnar

Abstract: Metacarbonate assemblages in high-grade metamorphic terranes often pose challenges when trying to distinguish between mantle-derived carbonatite and sedimentary carbonate protoliths. We present a study of granulite-facies metacarbonate samples of the putative Munnar carbonatite described as decimeter-thick dikes and veins, and layers of a meter-thick metacarbonate and calc-silicate assemblage, respectively. Thin sections of the metacarbonate dike samples show absence of pyrochlore and ubiquitous scapolite, titanite, wollastonite, and detrital zircons are compatible with impure limestone protoliths. Nd and Sr isotope compositions indicate protoliths with Paleoproterozoic crustal residence times which contrast the mantle sources of Indian and global carbonatites. Trace-element patterns display the characteristics of upper crust, and Ce- and Y-anomalies in a number of samples suggest protolith formation under marine conditions. Carbon and oxygen isotope compositions of the metacarbonate samples interlayered with calc-silicate rocks are similar to those in marine limestone. The metacarbonate dikes, however, show mantle-like compositions which are interpreted as reflecting equilibration with mantle-derived CO2 during granulite-facies metamorphism. The dikes yielded a U-Pb zircon crystallization age of 1020 ± 70 Ma and a cross-cutting quartz syenite, thought to be cogenetic, a magmatic age of 620 ± 35 Ma; the hosting gneiss provided a magmatic age of 2452 ± 14 Ma. We conclude that the layered metacarbonate and calc-silicate rocks represent a former marine limestone and marl sequence and the metacarbonate dikes and veins small-volume melts of crust-derived carbonate-rich sediment.
DS200612-1122
2006
Rajesh, V.J.Rajesh, V.J., Arai, S.Baddelyite apatite spinel phlogopite (BASP) rock in Achankovil shear zone, South India, as a probable cumulate from melts of carbonatite affinity.Lithos, Vol.90, 1-2, August pp. 1-18.IndiaCarbonatite
DS201012-0608
2010
Rajesh, V.J.Rajesh, V.J., Arai, S., Santosh, M., Tamura, A.LREE rich hibonite in ultrapotassic rocks in southern India.Lithos, Available in press formated 11p.IndiaAlkalic
DS1993-1279
1993
Rajlich, P.Rajlich, P.Riedel shear: a mechanism for crenulation cleavageEarth Science Reviews, Vol. 34, pp. 167-195GlobalStructure -reidel shears, Review
DS200812-0323
2008
RajuEriksson, P.G., Banerjee, S., Nelson, D.R., Rigby, M.J., Catuneanu, O., Sarkar, S., Roberts, R.J., Ruban, Mtimkulu, RajuA Kaapvaal Craton debate: nucleus of an early small supercontinent or affected by an enhanced accretion event?Gondwana Research, In press available, 82p.Africa, South AfricaSupercontinents
DS2003-1147
2003
Raju, A.N.Reddy, K.S., Raju, A.N.The physical and textural characteristics of termite mounds from Podili and TalupulaJournal of the Geological Society of India, Vol. 61, 6, June, pp. 693-98.IndiaBlank
DS200412-1644
2003
Raju, A.N.Reddy, K.S., Raju, A.N.The physical and textural characteristics of termite mounds from Podili and Talupula areas, Andhra Pradesh.Journal of the Geological Society of India, Vol. 61, 6, June, pp. 693-98.IndiaGeomorphology - not specific to diamonds
DS2003-1125
2003
Raju, D.C.Raju, D.C.LIMAT: a computer program for least squares inversion of magnetic anomalies overComputers and Geosciences, Vol. 29, 1, pp. 91-98.GlobalComputer - program
DS2001-0960
2001
Raju, D.C.I.Raju, D.C.I., Thakur, K.S., Shrivastava, S.K., Sambandam, S.T., Khoitpal, A.S.Ground evaluation of aeromagnetic and spectrometric and other integrated dat a inIndia Geological Survey Records, No. 135, 2, p. 129-131.IndiaNews item - diamond discoveries
DS200612-1294
2001
Raju, D.C.L.Shrivastava, S.K., Roy, A., Thakur, K.S., Raju, D.C.L., Muthuraman, K.Integrated approach for locating kimberlites in eastern parts of Bastar Craton in Chhattisgarh and Orissa States.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 615-621.India, Chhattisgarh, OrissaDiamond exploration - geochemistry
DS1975-1194
1979
Raju, K.C.C.Raju, K.C.C., Kareemuddin, M.D., Prabhakara, R.P.Operation AnantapurIndia Geological Survey Miscellaneous Publishing, No. 47, PP. 12-16.India, Andhra PradeshBlank
DS1970-0371
1971
Raju, K.K.Narasimham, C.V., Raju, K.K.Photogeologic Studies in and Around Panna, District, A.pI.p.i. Dehra Dun Unpubl. Report, India, Andhra PradeshPhotgeology
DS200812-0936
2008
Raju, K.N.Rao, D.V.S., Balaram, V., Raju, K.N., Sridhar, D.N.Paleoproterozoic boninite like rocks in an intracratonic setting from northern Bastar Craton, central India.Journal of the Geological Society of India, Vol. 27, 3, pp. 373-380.IndiaBoninites
DS1991-1394
1991
Raju, M.V.B.Raju, M.V.B., Misra, G.B.An evaluation of the undiscovered mineral resources of India based on the concept of unit regional valueMath. Geol, Vol. 23, No. 6, August pp. 841-852IndiaGeostatistics, Mineral resources
DS2003-1212
2003
Raju, P.S.Sarkar, D., Kumar, M.R., Saul, J., Kind, R., Raju, P.S., Chadha, R.K., ShuklaA receiver function perspective of the Dharwar craton ( India) crustal structureGeophysical Journal International, No. 154, 1, pp. 205-211.IndiaBlank
DS200412-1731
2003
Raju, P.S.Sarkar, D., Kumar, M.R., Saul, J., Kind, R., Raju, P.S., Chadha, R.K., Shukla, A.K.A receiver function perspective of the Dharwar craton ( India) crustal structure.Geophysical Journal International, No. 154, 1, pp. 205-211.IndiaGeophysics - seismics
DS200512-0588
2004
Raju, P.S.Kumar, M.R., Raju, P.S., Devi, E.U., Saul, J., Ramesh, D.S.Crustal structure variations in northeast India from converted phases.Geophysical Research Letters, Vol. 31, 17, Sept. 16, L17605IndiaTectonics
DS200512-0889
2005
Raju, P.S.Ramesh, D.S., Kumar, M.R., Devi, E.U., Raju, P.S., Yaun, X.Moho geometry and upper mantle images of northeast India.Geophysical Research Letters, Vol. 32, 14, July 28, L14301IndiaGeophysics - seismics
DS200612-1312
2006
Raju, P.S.Singh, A., Kumar, M.R., Raju, P.S., Ramesh, D.S.Shear wave anisotropy of the northeast Indian lithosphere.Geophysical Research Letters, Vol. 33, 16, August 28, L16302.IndiaGeophysics - seismics
DS200712-0866
2007
Raju, S.Rajendra Prasad, B., Kesava Rao, G., Mall, D.M., Koteswarar Rao, P., Raju, S., Reddy, SridherTectonic implications of seismic reflectivity pattern observed over the Precambrian southern granulite terrain, India.Precambrian Research, Vol. 153, 1-2, pp. 1-10.IndiaGeophysics - seismics
DS201805-0971
2018
Raju, V.V.Phani, R., Raju, V.V., Srinivas, M.Petrological and geochemical characteristics of a shoshonitic lamprophyre, Sivarampet, Wajrakarur, kimberlite field, southern India.Journal of Applied Geology and Geophysics (IOSR), Vol. 6, 2, pp. 55-69. pdfIndiashoshonite

Abstract: Field geological, petrographic and geochemical characteristics of a lamprophyre intrusion, presumably of plug-type, at Sivarampet (SPL), occurring within the Wajrakarur kimberlite field (WKF) to the west of Cuddapah basin, are presented and discussed. The lamprophyre intrusion occurs as brecciated outcrop with angular country rock granitoid clasts and also it forms stringers/veinlets within the granitic country rock. The melanocratic rock displays panidiomorphic/porphyritic texture, typical of lamprophyres, comprising clinopyroxene, biotite, phlogopite set in a groundmass of feldspar, magnetite and spinel. Plagioclase is dominant feldspar. The K2O/Na2O ratio ranges from 1.55 to 1.89 wt %, making it distinctly potassic and brings out its shoshonitic behaviour. The fractionated chondrite normalised patterns of REE (with average (La/Yb)N= 21.01 ppm) implies involvement of an enriched mantle source while depleted values of Nb, Hf, Th and U concentrations indicate prevalence of subducted component in the mantle source. The concentrations of Rb, Sr and Ba indicate presence of phlogopite in the source. Based on the mineral assemblages, the SPL can be classified as calc-alkaline variety; however, its geochemistry shows characteristics of both alkaline and calc-alkaline varieties. The moderate Mg# (52 to 55.6) and low concentration of Ni (95.61 to 112.4 ppm) in the bulk rock indicate a low degree of partial melting of magmatic fluid from enriched asthenospheric mantle which underwent fractionation of olivine and pyroxene, subsequently producing lamprophyre magma. Recent discovery of diamonds in shoshonitic lamprophyres of Canada, appeals further investigations on diamondiferous nature of similar rock types of the WKF.
DS201805-0972
2017
Raju, V.V.N.Phani, R., Raju, V.V.N.A new kimberlite pipe in Balkamthota Vanka, Pennahobilam, Anantapur district, Andhra Pradesh, India. Field aspects and preliminary investigations.Periodico di Mineralogia, Vol. 86, pp. 213-228. pdfIndiadeposit - Balkamthota Vanka

Abstract: Systematic closely spaced geological traverses conducted in the year 2010, in Lattavaram Kimberlite Cluster (LKC) of Anantapur district, Andhra Pradesh, India, have led to the discovery of a new kimberlite pipe outcrop in the river bed of Balkamthota Vanka (name of the stream used by local farmers) at its confluence with Penna River, close to Pennahobilam. This new pipe occurs at a distance of 1.5 km in NE direction to hitherto reported pipes-5 and 13 occurring at Muligiripalli and Tummatapalli respectively in the LKC of the Wajrakarur Kimberlite Field (WKF). With this pipe, the total number of kimberlite pipes in the WKF raises to 48, considering all the kimberlites discovered by various public and private organizations so far. Preliminary petrography, geochemistry, petrogenetic aspects and diamond prospectivity of the new occurrence have been presented here. Mineralogically, the kimberlite constitutes olivine macrocrysts, serpentinsed olivine psuedomorphs with xenocrystic ilmenite, phlogopite, perovskite, magnetite, Cr-diopside, garnet along with calcite veins. The kimberlite is classified as hypabyssal macrocrystic calcite- phlogopite kimberlite. Mineralogically, the new kimberlite pipe appears as archetypal Group- I kimberlite however, geochemically; the kimberlite shows character of both Group- I and II varieties, more close to lamproitic character. Although it is too early to comment, based on limited analyses carried out in this study, the diamond potentiality of this pipe is not encouraging; it is noteworthy that it highly warrants detailed investigations involving bulk rock geochemistry and drilling to assess its definite geochemical status, petrogenesis and diamond potentiality.
DS1970-0392
1971
Rake, A.Rake, A.Smuggling Hits Tanzania Diamond IndustryAfr. Dev., MARCH, PP. 14-15.Tanzania, East AfricaHistory
DS201512-1920
2015
RakeshGokhale, M., Madhura, Somani, R., RakeshFullerenes: chemistry and its applications.Mini-Reviews in Organic Chemistry, Vol. 12, 4, pp. 355-366.TechnologyFullerenes

Abstract: Fullerenes being allotropes of carbon, have been considered as new class of molecules. Unlike diamond and graphite, this is made up of hollow carbon cage structure. The idea of spheroidal cage structures of C60 arose from construction of geodesic domes made by renowned architect Buckminster Fuller. Although fullerenes have low solubility in physiological media they finds promising biological applications. The photo, electrochemical and physical properties of C60 and other fullerene derivatives finds applications in medical fields. The ability of fullerenes to fit inside the hydrophobic cavity of HIV proteases makes them potential inhibitor for substrates to catalytic active site of enzyme. It possesses radical scavenging and antioxidant property. At the same time, when it exposed to light it can form singlet oxygen in high quantum yields which with direct electron transfer from excited state of fullerenes and DNA bases finally results in cleavage of DNA. The fullerenes are also used as a carrier for gene and drug delivery system. The associated low toxicity of fullerenes is sufficient to attract the researchers for investigation of these interesting molecules.
DS201502-0102
2015
Rakevich, A.L.Skuzovatov, S.Yu., Zedgenizov, D.A., Rakevich, A.L., Shatsky, V.S., Martynovich, E.F.Multiple growth events in diamonds with cloudy Micro inclusions from the Mir kimberlite pipe: evidence from the systematics of optically active defects.Russian Geology and Geophysics, Vol. 56, 1, pp. 330-343.RussiaDeposit - Mir
DS201507-0328
2015
Rakevich, A.L.Mironov, V.P., Rakevich, A.L., Stepanov, F.A., Emelyanova, A.S., Zedgenizov, D.A., Shatsky, V.S., Kagi, H., Martynovich, E.F.Luminescence in diamonds of the Sao Luiz placer ( Brazil).Russian Geology and Geophysics, Vol. 56, pp. 729-736.South America, BrazilDiamond luminesence
DS201603-0423
2016
Rakevich, A.L.Stepanov, F.A., Mironov, V.P., Rakevich, A.L., Shatsky, V.S., Zedgenizov, D.A., Martynovich, E.F.Red luminescence decay kinetics in Brazilian diamonds. ( Juina)Bulletin of the Russian Academy of Sciences. Physics ** IN ENG, Vol. 80, 1, pp. 74-77.South America, BrazilDiamond formation

Abstract: Luminescence kinetics in the temperature range of 80 480 K and the red region of the spectrum is studied for Brazilian diamonds. Components with decay time constants of 23 and 83 ns are observed at room temperature after being excited by laser radiation with wavelengths of 375 and 532 nm, which differs considerably from the data published earlier for the luminescence kinetics of NV 0- and NV -centers.
DS201707-1366
2017
Rakevich, A.L.Shuzovatov, S.Y., Zedgenizov, D.A., Rakevich, A.L.Spectroscopic constraints on growth of Siberian mixed habit diamonds.Contributions to Mineralogy and Petrology, Vol. 172, pp. 46-64.Russiadeposit -Mir, Internationalnaya, Udachnaya, Nyurbinskaya

Abstract: Notable within-crystal variability of mineralogical and geochemical properties of single natural diamonds are commonly attributed to changing chemistry of parental fluids, sources of carbon and redox conditions of diamond precipitation. A distinct type of compositional heterogeneity (mixed-habit structure) is well-known to occur in diamonds as well as in many other minerals due to purely “structural” reasons that are unequal crystal chemistry of crystallographically different faces and selective absorption and fractionation of impurities between adjacent growth pyramids. Based on the combined cathodoluminescence, Fourier-transformed infrared spectroscopy and photoluminescence spectroscopy, study of nine diamond crystals with different growth histories and external morphology, but all showing mixed-habit patterns at different growth stages, we show that mixed-diamonds may grow in closed system conditions or with a slowly decreasing growth rate from a media with a much lower impurity content than previously thought. Intracrystal nitrogen distribution seems to be a function of growth rate even in the cases of unusual impurity partitioning between growth sectors. Generally poor with IR-active hydrogen at moderate nitrogen aggregation parameters, studied diamonds likely resemble the low hydrogen content from the growth medium that, for cubic diamonds, was typically suggested hydrogen-rich and a crucial factor for growth of cubic and mixed-habit diamonds. We also show that mixed-habit diamond growth may occur not only in peridotitic suite but also in an extended field of geochemical affinities from high-Ni to low-Ni or maybe even Ni-free environments, such as pyroxenitic or eclogitic.
DS201909-2086
2019
Rakhamanova, M.I.Shatsky, V.S., Nadolinny, V.A., Yuryeva, O.P., Rakhamanova, M.I., Komarovskikh, A.Yu.Features of the impurity composition of diamonds from placers of the northeastern Siberian craton.Doklady Earth Sciences, Vol. 486, 2, pp. 644-646.Russia, Siberiadiamond morphology

Abstract: Diamond crystals from the Istok (25 crystals) and Mayat (49 crystals) placers were studied using the EPR, IR, and luminescence methods. The total content of impurity nitrogen in forms of A, B, and C (P1) centers ranges from 50 to 1200 ppm. According to the EPR spectroscopy, the presence of nitrogen C (P1), N3V and nitrogen-titanium OK1, N3, NU1 impurity centers was established in the investigated crystals. For 18 crystals from the Istok placer, the N3 nitrogen-titanium center was observed in the EPR spectra, but in the luminescence spectra there was no 440.3 nm system, which was previously attributed to the manifestation of the N3 defect. It is more likely that the nitrogen-titanium N3 EPR center corresponds to the electron-vibrational system 635.7 nm, which is observed in the luminescence spectra of these crystals. Crystals from the Istok placer contain the OK1, N3, and NU1 centers, but luminescence attributed to the oxygen-containing centers is absent in the region of 610-670 nm. For the Mayat placer crystals, the reverse situation was observed. The luminescence ascribed to the oxygen-containing centers was detected for 17 crystals, but there were no OK1, N3, and NU1 centers according to the EPR and luminescence. This result contradicts the arguments of a number of authors about the oxygen nature of these defects. For 5 crystals from the Mayat placer, the nickel impurity was registered. This indicates the presence of ultrabasic paragenesis diamond crystals in this placer.
DS1984-0782
1984
Rakhmania, A.V.Yakolev, E.N., Voronov, O.A., Rakhmania, A.V.Synthesis of Diamonds from HydrocarbonsSoviet Journal of Superhard Materials, Vol. 6, No. 4, pp. 9-12RussiaDiamond Morphology
DS1999-0577
1999
Rakhmania, A.V.Rakhmania, A.V., Yakovlev, E.N.Experimental modeling of the natural synthesis of polycrystalline diamondGeochemistry International, Vol. 37, No. 7, July pp. 678-82.GlobalDiamond morphology
DS1987-0820
1987
Rakhmanina, A.V.Yakovlev, E.N., Voronov, O.A., Rakhmanina, A.V.Polycrystalline diamond aggregates obtained by using hydrocarbons.(Russian)Sverktverd. Mater.(Russian), No. 2, pp. 3-5GlobalDiamond synthesis
DS200712-0223
2007
Rakhmanina, A.V.Davydov, V.A., Rakhmanina, A.V., Rols, S., Agafonov, V., Pulikkathara, M.X., Wal, R.V., Khabashesku, V.N.Size dependent phase transition of diamond to graphite at high pressures.Journal of Physical Chemistry , Vol. 111, no. 35, pp. 12918-12925. Ingenta 1074185621TechnologyUHP
DS200712-0290
2006
Rakhmaninia, A.Ekimov, E., Sidorov, V., Rakhmaninia, A., Melnik, N., Timofeev, M., Sadykov, R.Synthesis, structure and physical properties of boron doped diamond.Inorganic Materials, Vol. 42, 11, Nov. pp. 1198-1204.TechnologyDiamond mineralogy
DS202010-1852
2020
Rakhmanova, M.Komarovskikh, A., Rakhmanova, M., Yuryeva, O., Nadolinny, V.Infrared, photoluminescence, and electron paramagnetic resonance characteristic features of diamonds from Aikhal pipe, (Yakutia).Diamond & Related Materials, Vol. 109, 108045, 9p. PdfRussiadeposit - Aikhal

Abstract: The diversity of the defects in the collection (50 samples) of diamonds from the Aikhal pipe (Yakutia) has been studied with IR, PL, and EPR spectroscopy. The specific features of crystals have been established; the obtained information leads to the discussion about the diamond formation and growth conditions. One of the specific features observed is a high concentration of platelets. According to the platelet behavior, most of the crystals are regular suggesting the growth temperature to be 1100-1200 °C. The concentrations of A and B defects have been evaluated and the same temperature conditions have been obtained according to the Taylor diagram. Using the EPR spectroscopy, the C and N3V centers have been found in many crystals suggesting the aggregation of nitrogen during residence in the mantle at high temperatures. An interesting feature has been observed in the PL spectra. For most crystals, the spectrum with ZPL at 563.5 nm is very intensive. The structure of the observed defect is remaining unknown, the spectrum disappears as a result of annealing at 600 °C indicating the interstitial-vacancy annihilation mechanism.
DS201212-0507
2012
Rakhmanova, M.I.Nadolinny, V.A., Yuryeva,O.P., Rakhmanova, M.I., Shatsky, V.S., Palyanov, Y.N., Kupriyanov, I.N., Zedgenizov, D.A., Ragozin, A.L.Distribution of OK1, N3 and NU1 defects in diamond crystals of different habits.European Journal of Mineralogy, Vol. 24, 4, pp. 645-650.TechnologyDiamond morphology
DS201412-0721
2014
Rakhmanova, M.I.Rakhmanova, M.I., Nadolinny, V.A., Yuryeva, O.P., Pokhilenko, N.P.Pecularities of nitrogen impurity aggregation in diamonds from the Sytykanskaya pipe, Yakutia.European Journal of Mineralogy, Vol. 27, 1, pp. 51-56.Russia, YakutiaDeposit - Sytykanskaya
DS201503-0170
2015
Rakhmanova, M.I.Rakhmanova, M.I., Nadolinny, V.A., Yuryeva, O.P., Pokhilenko, N.P., Logvinova, A.M.Pecularities of nitrogen impurity aggregation in diamonds from the Sytykanskaya pipe, Yakutia.European Journal of Mineralogy, Vol. 27, pp. 51-56.Russia, YakutiaDeposit - Sytykanskaya
DS201509-0440
2015
Rakhmanova, M.I.Yuryeva, O.P., Rakhmanova, M.I., Nadolinny, V.A., Zedgenizov, D.A., Shatsky, V.S., Kagi, H., Komarovskikh, A.Yu.The characteristic photoluminescence and EPR features of superdeep diamonds ( Sao Luis, Brazil).Physics and Chemistry of Minerals, In press available 16p.South America, Brazil, Mato GrossoDeposit - Juina area

Abstract: Photoluminescence (PL) spectroscopy and electron paramagnetic resonance (EPR) were used for the first time to characterize properties of superdeep diamonds from the São-Luis alluvial deposits (Brazil). The infrared measurements showed the low nitrogen content (>50 of 87 diamonds from this locality were nitrogen free and belonged to type IIa) and simultaneously the extremely high level of nitrogen aggregation (pure type IaB being predominant), which indicates that diamonds under study might have formed under high pressure and temperature conditions. In most cases, PL features excited at various wavelengths (313, 473, and 532 nm) were indicative of different growth and post-growth processes during which PL centers could be formed via interaction between vacancies and nitrogen atoms. The overall presence of the 490.7 nm, H3, and H4 centers in the luminescence spectra attests to strong plastic deformations in these diamonds. The neutral vacancy known as the GR1 center has probably occurred in a number of crystals due to radiation damage in the post-growth period. The 558.5 nm PL center is found to be one of the most common defects in type IIa samples which is accompanied by the EPR center with g-factor of 2.00285. The 536 and 576 nm vibronic systems totally dominated the PL spectra of superdeep diamonds, while none of "normal" diamonds from the Mir pipe (Yakutia) with similar nitrogen characteristics showed the latter three PL centers.
DS201511-1892
2015
Rakhmanova, M.I.Yuryeva, O.P., Rakhmanova, M.I., Nadolinny, V.A., Zedgenizov, D.A., Shatsky, V.S., Kagi, H., Komarovskikh, A.Yu.The characteristic photoluminescence and EPR features of superdeep diamonds ( Sao-Luis, Brazil).Physics and chemistry of Minerals, Vol. 42, 9, pp. 707-722.South America, BrazilSao-Luis alluvials

Abstract: Photoluminescence (PL) spectroscopy and electron paramagnetic resonance (EPR) were used for the first time to characterize properties of superdeep diamonds from the São-Luis alluvial deposits (Brazil). The infrared measurements showed the low nitrogen content (>50 of 87 diamonds from this locality were nitrogen free and belonged to type IIa) and simultaneously the extremely high level of nitrogen aggregation (pure type IaB being predominant), which indicates that diamonds under study might have formed under high pressure and temperature conditions. In most cases, PL features excited at various wavelengths (313, 473, and 532 nm) were indicative of different growth and post-growth processes during which PL centers could be formed via interaction between vacancies and nitrogen atoms. The overall presence of the 490.7 nm, H3, and H4 centers in the luminescence spectra attests to strong plastic deformations in these diamonds. The neutral vacancy known as the GR1 center has probably occurred in a number of crystals due to radiation damage in the post-growth period. The 558.5 nm PL center is found to be one of the most common defects in type IIa samples which is accompanied by the EPR center with g-factor of 2.00285. The 536 and 576 nm vibronic systems totally dominated the PL spectra of superdeep diamonds, while none of "normal" diamonds from the Mir pipe (Yakutia) with similar nitrogen characteristics showed the latter three PL centers.
DS201603-0434
2015
Rakhmanova, M.I.Yureva, O.P., Rakhmanova, M.I., Nadolinny, V.A., Zedgenizov, D.A., Shatsjy, V.S., Kagi, H., Komarovskikh, A.Y.The characteristic photoluminesence and EPR features of super deep diamonds ( Sao-Luis, Brazil).Physics and Chemistry of Minerals, Vol. 42, 9, pp. 707-722.South America, BrazilDeposit - Sao-Luis

Abstract: Photoluminescence (PL) spectroscopy and electron paramagnetic resonance (EPR) were used for the first time to characterize properties of superdeep diamonds from the São-Luis alluvial deposits (Brazil). The infrared measurements showed the low nitrogen content (>50 of 87 diamonds from this locality were nitrogen free and belonged to type IIa) and simultaneously the extremely high level of nitrogen aggregation (pure type IaB being predominant), which indicates that diamonds under study might have formed under high pressure and temperature conditions. In most cases, PL features excited at various wavelengths (313, 473, and 532 nm) were indicative of different growth and post-growth processes during which PL centers could be formed via interaction between vacancies and nitrogen atoms. The overall presence of the 490.7 nm, H3, and H4 centers in the luminescence spectra attests to strong plastic deformations in these diamonds. The neutral vacancy known as the GR1 center has probably occurred in a number of crystals due to radiation damage in the post-growth period. The 558.5 nm PL center is found to be one of the most common defects in type IIa samples which is accompanied by the EPR center with g-factor of 2.00285. The 536 and 576 nm vibronic systems totally dominated the PL spectra of superdeep diamonds, while none of “normal” diamonds from the Mir pipe (Yakutia) with similar nitrogen characteristics showed the latter three PL centers.
DS201612-2351
2016
Rakhmanova, M.I.Zedgenizov, D.A., Kalinina, V.V., Reutsky, V.N., Yuryeva, O.P., Rakhmanova, M.I.Regular cuboid diamonds from placers on the northeastern Siberian platform.Lithos, Vol. 265, pp. 125-137.Russia, SiberiaDiamond morphology

Abstract: Alluvial placers of the northeastern Siberian Platform are characterized by a specific diamond population: regular cuboids, forming a continuous color series from yellowish-green to yellow and dark orange. This is the first comprehensive study of a large number of cuboid diamonds focusing on their morphology, N content and aggregation state, photoluminescence, C isotopic composition and inclusions. The cuboids are cubic (i.e. nearly flat faced) to subrounded crystals; most of them are resorbed. The cathodolominescence images and the birefringence patterns show that many cuboid diamonds record deformation. The cuboid diamonds are characterized by unusual FTIR spectra with the presence of C- (single nitrogen atom) and A- (pair of neighbour nitrogen atoms) centers, and two centers of unknown origin, termed X and Y. The presence of single substitutional nitrogen defects (C centers) in all cuboid diamonds testifies either storage in the mantle at relatively cool conditions or formation just prior to eruption of their host kimberlites. The studied diamonds are also characterized by the presence of specific set of luminescence centers: N3, H3, S1, NVo and NV-, some of which are suggested to have formed during deformation subsequent to diamond growth. The cuboid diamonds show a wide range of carbon isotope compositions from mantle-like values towards strongly 13C depleted compositions (- 6.1 to - 20.2‰ d13C). Combined with the finding of an eclogitic sulfide inclusion, the light carbon isotope compositions link the formation of the studied cuboids to deeply subducted basic protoliths, i.e. former oceanic crust.
DS201706-1111
2017
Rakhmanova, M.I.Yuryeva, O.P., Rakhmanova, M.I., Zedgenizov, D.A.Nature of type 1aB diamonds from the Mir kimberlite pipe (Yakutia): evidence from spectroscopic observation.Physics and Chemistry of Minerals, in press available 13p.Russia, Yakutiadeposit - Mir
DS201711-2536
2017
Rakhmanova, M.I.Yuryeva, O.P., Rakhmanova, M.I., Zedgenizov, D.A.Nature of type IaB diamonds from the Mir kimberlite pipe ( Yakutia): evidence from spectroscopic observation.Physics and Chemistry of Minerals, Vol. 44, 9, pp. 655-667.Russia, Yakutiadeposit - Mir

Abstract: In this study, the specific features of structural defects of type IaB diamonds from the Mir kimberlite pipe (Yakutian diamondiferous province) have been characterized using FTIR and photoluminescence spectroscopy. Mineral inclusions in these diamonds [olivine (Ol), orthopyroxene (OPx), chromite (Chr), sulphide (Sf)] correspond to associations of peridotite rocks at the base of the lithosphere. Nitrogen content in type IaB diamonds shows significant variations, suggesting different growth media and/or several growth stages. A specific feature of these diamonds is the absence or very small amount of platelets, which may be related to annealing during their long-term residence at the temperatures of the base of the lithosphere. All studied diamonds show the presence of hydrogen defects that are active in IR spectra with an intense line at 3107 cm-1, and additional weaker lines at 3085 and 3237 cm-1, which correlated with high nitrogen content. Type IaB diamonds are also characterized by the presence of nitrogen-nickel luminescence centres S2, S3 and 523.2 nm. This feature distinguishes them from superdeep diamonds with extreme nitrogen aggregation states, which clearly attest to different growth conditions and crystallization media of type IaB diamonds from the Mir kimberlite pipe.
DS202002-0211
2020
Rakhmanova, M.I.Nadolly, V.A., Shatsky, V.S., Yuryeva, O.P., Rakhmanova, M.I., Komarovskikh, A.Yu., Kalinin, A.A., Palyanov, Yu.N.Formation features of N3V centers in diamonds from the Kholomolokh placer in the Northeast Siberian craton.Physics and Chemistry of Minerals, Vol. 47, 4, 7p. PdfRussia, Siberiadeposit - Khololmolokh

Abstract: In recent years, despite significant progress in the development of new methods for the synthesis of diamond crystals and in their post-growth treatment, many questions remain unclear about the conditions for the formation and degradation of aggregate impurity nitrogen forms. Meanwhile, they are very important for understanding (evaluating) the origin, age, and post-growth conditions of natural diamonds. In the present work, an attempt was made to analyze the causes of the formation of high concentrations of N3V centers in natural IaB-type diamonds from the Kholomolokh placer (the Northeast Siberian craton). The possibility of decay of B centers during the plastic deformation of diamonds is analyzed and experiments on the high-temperature annealing of diamonds containing B centers are reported. The formation of N3V centers during the destruction of the B centers at high-pressure annealing of crystals has been established by experiment. It is assumed that, in the post-growth period, diamond crystals were exposed to tectono-thermal stages of raising the superplumes of the Earth's crust of the Siberian craton.
DS202005-0774
2020
Rakhmanova, M.I.Yuryeva, O.P., Rakhmanova, M.I., Zedgenizov, D.A., Kalinina, V.V.Spectroscopic evidence of the origin of brown and pink diamonds family from Internatsionalnaya kimberlite pipe ( Siberian craton).Physics and Chemistry of Minerals, Vol. 47, 20 doi.org/10/1007/ s00269-020-01088-5 19p. PdfRussiadeposit - International

Abstract: New spectroscopic data were obtained to distinguish the specific features of brown and pink diamonds from Internatsionalnaya kimberlite pipe (Siberian craton). It is shown that pink and brown samples differ markedly in the content and degree of aggregation of nitrogen defects. Pink diamonds generally have higher nitrogen content and a lower aggregation state compared to brown samples, which often show significant variations in nitrogen content and aggregation state between different growth zones. The 491 and 576 nm luminescent centres, which are signs of deformed brown diamonds, are absent or of low intensity in pink diamonds implying that high nitrogen content predominantly in A form in the pink diamonds had stiffened the diamonds against natural plastic deformation. The GR1 centre, formed by a neutrally charged vacancy, was observed only in pink diamonds, which may be due to their formation and storage in the mantle at lower-temperature conditions. Mineral inclusions indicate peridotitic and eclogitic paragenesis for studied brown and pink diamonds, respectively. It is suggested that brown diamonds have been formed in a primitive mantle at higher temperatures and/or stored there much longer.
DS1987-0601
1987
Rakhmedov, U.Rakhmedov, U.Calcite from carbonatite rocks.(Russian)Zap. Uzbekistan. Otdel. Vses. Mineral. Obshch., (Russian), Vol. 40, pp. 75-78RussiaCrystallography, Calcite
DS200412-1614
2004
Rakin, V.I.Rakin, V.I.The shape of nonplane-faced diamonds.Doklady Earth Sciences, Vol. 395, 2, pp. 242-245.TechnologyDiamond morphology
DS200412-1818
2004
Rakin, V.I.Silaev, V.I., Chaikovskii, I.I., Rakin, V.I., Filippov, Y.N.A new type of synthetic xenomineral inclusions in diamond.Doklady Earth Sciences, Vol. 394, 1, Jan-Feb. pp. 53-57.RussiaDiamond inclusions
DS201112-0840
2010
Rakin, V.I.Rakin, V.I., Petrovsky, V.A., Sukharev, A.E., Martins, M.Morphological crystallography of Brazilian diamonds.Vestnik Komi FAN, **in Russian copy available, No. 10, pp. 2-7.South America, BrazilDiamond morphology
DS201212-0577
2012
Rakin, V.I.Rakin, V.I.Mechanical abrasion surfaces on diamond crystals.Doklady Earth Sciences, Vol. 442, 1, pp. 105-108.RussiaDiamond morphology
DS201605-0883
2015
Rakin, V.I.Petrovsky, V.A., Silaev, V.I., Sukharev, A.E., Golubeva, I.I., Rakin, V.I., Lutoev, V.P., Vasiliev, E.A.Placer forming Diamondiferous rocks and diamonds of Eastern Brazil. IN RUSS Eng. Abs.Thesis, Vestnik Permskogo Universitecta IN RUSS, Vol. 1, 30, pp. 33-59.South America, BrazilAlluvials
DS201702-0235
2016
Rakin, V.I.Rakin, V.I., Kovalchuk, O.Y., Pomazansky, B.S.Dissymmetrization of artificial and natural diamonds,Doklady Earth Sciences, Vol. 471, 2, pp. 1303-1306.TechnologyDiamond crystallography

Abstract: The occurrence rates of combinatorial types of simple polyhedra {111} are analyzed for natural and artificial diamonds. The empirical occurrence rates of 14 possible polyhedra in an isotropic environment are obtained based on numeral simulation of growth forms of octahedral crystals by the Monte-Carlo method. The phenomenon of dissymmetrization by Curie’s principle related to the crystallization conditions is established for artificial and natural diamonds.
DS1985-0600
1985
Rakmani, A.V.Serebrya, N.R., Losev, V.G., Voronov, O.A., Rakmani, A.V., Yakol.The Morphology of Diamond Crystals Synthesized from Hydrocarbons. a Technical Note.Kristallogr., Vol. 30, No. 5, PP. 1026-1027.RussiaDiamond Morphology, Synthetics
DS202012-2224
2020
Rakmanova, M.Komarovskikh, A., Rakmanova, M., Yuryeva, O., Nadolinny, V.Infrared, photoluminescence, and electron paramagnetic resonance characteristic features of diamonds from the Aikhal pipe ( Yakutia).Diamond and Related Materials, Vol. 109, 108045, 9p. PdfRussiadeposit - Aikhal

Abstract: The diversity of the defects in the collection (50 samples) of diamonds from the Aikhal pipe (Yakutia) has been studied with IR, PL, and EPR spectroscopy. The specific features of crystals have been established; the obtained information leads to the discussion about the diamond formation and growth conditions. One of the specific features observed is a high concentration of platelets. According to the platelet behavior, most of the crystals are regular suggesting the growth temperature to be 1100-1200 °C. The concentrations of A and B defects have been evaluated and the same temperature conditions have been obtained according to the Taylor diagram. Using the EPR spectroscopy, the C and N3V centers have been found in many crystals suggesting the aggregation of nitrogen during residence in the mantle at high temperatures. An interesting feature has been observed in the PL spectra. For most crystals, the spectrum with ZPL at 563.5 nm is very intensive. The structure of the observed defect is remaining unknown, the spectrum disappears as a result of annealing at 600 °C indicating the interstitial-vacancy annihilation mechanism.
DS1997-0137
1997
Rakoczy, H.Bruns, P., Rakoczy, H., Dullo, W. Ch.Slow sedimentation and Ir anomalies at the Cretaceous/ Tertiary boundaryGeologische Rundschau, Vol. 86, No. 1, pp. 168-177GlobalBoundary, Iridium anomalies
DS202103-0413
2021
Rakotomalala, A.G.Stoudmann, N., Reibelt, L.M., Rakotomalala, A.G., Randriamanjakahasina, O., Garcia, C.A., Waeber, P.O.A double edged sword: realities of artisanal and small scale mining for rural people in the Alaotra region of Madagascar. ** not specific to diamondsNatural Resources Forum, Vol 45 pp. 87-102. pdfAfrica, Madagascaralluvials

Abstract: A growing number of people are entering the artisanal and small-scale mining (ASM) sector worldwide. In Madagascar, millions of individuals depend on this informal activity. Through a case study in the Alaotra-Mangoro region of Madagascar, our research aimed to understand the "bottom-up" dynamics and ripple effects of the sector, by looking at the realities for rural communities where inhabitants are both directly and indirectly affected by ASM. We were interested in community members' and miners' perceptions of the socio-economic and environmental impacts of ASM, and in identifying the factors attracting people living in one of the country's agricultural hubs to this activity. Our results show a wide diversity of push and pull factors leading people to enter the sector. Although many positive impacts of ASM exist for miners and communities within the vicinity of mines, most miner participants considered themselves worse off since starting to mine, highlighting the high risk and low probability of return of ASM. ASM's potential for local and national development will remain squandered if its negative impacts continue to go unmanaged. Accounting for local contexts and the ripple effects of ASM will be crucial in achieving safety and security for miners, and to tap into the benefits it may offer communities while minimising environmental damage.
DS201801-0050
2017
Rakotondraibe, T.Pratt, M.J., Wysession, M.E., Aleqabi, G., Wiens, D.A., Nyblade, A., Shore, P., Rambolamanana, G., Andriampenomanana, F., Rakotondraibe, T., Tucker, R.D., Barruol, G., Rindraharisaona, E.Shear velocity structure of the crust and upper mantle of Madagascar derived from surface wave tomography.Earth and Planetary Science Letters, Vol. 458, 1, pp.405-417.Africa, Madagascargeophysics - seismics

Abstract: The crust and upper mantle of the Madagascar continental fragment remained largely unexplored until a series of recent broadband seismic experiments. An island-wide deployment of broadband seismic instruments has allowed the first study of phase velocity variations, derived from surface waves, across the entire island. Late Cenozoic alkaline intraplate volcanism has occurred in three separate regions of Madagascar (north, central and southwest), with the north and central volcanism active until <1 Ma, but the sources of which remains uncertain. Combined analysis of three complementary surface wave methods (ambient noise, Rayleigh wave cross-correlations, and two-plane-wave) illuminate the upper mantle down to depths of 150 km. The phase-velocity measurements from the three methods for periods of 8-182 s are combined at each node and interpolated to generate the first 3-D shear-velocity model for sub-Madagascar velocity structure. Shallow (upper 10 km) low-shear-velocity regions correlate well with sedimentary basins along the west coast. Upper mantle low-shear-velocity zones that extend to at least 150 km deep underlie the north and central regions of recent alkali magmatism. These anomalies appear distinct at depths <100 km, suggesting that any connection between the zones lies at depths greater than the resolution of surface-wave tomography. An additional low-shear velocity anomaly is also identified at depths 50-150 km beneath the southwest region of intraplate volcanism. We interpret these three low-velocity regions as upwelling asthenosphere beneath the island, producing high-elevation topography and relatively low-volume magmatism.
DS201709-1984
2017
Rakotondrazafy, A.F.M.Feneyrol, J., Giuliani, G., Demaiffe, D., Ohenstetter, D., Fallick, A.E., Dubessy, J., Martelet, J-E., Rakotondrazafy, A.F.M., Omito, E., Ichangi, D., Nyamai, C., Wamunyu, W.Age and origin of the tsavorite and tanzanite mineralozing fluids in the Neoproterozoic Mozambique metamorphic belt.The Canadian Mineralogist, Vol. 55, pp. 763-786.Africa, Kenya, Tanzania, Madagascartanzanite

Abstract: The genetic model previously proposed for tsavorite- (and tanzanite-) bearing mineralization hosted in the Neoproterozoic Metamorphic Mozambique Belt (stretching from Kenya through Tanzania to Madagascar) is refined on the basis of new Sm-Nd age determinations and detailed Sr-O-S isotope and fluid-inclusion studies. The deposits are hosted within meta-sedimentary series composed of quartzites, graphitic gneisses, calc-silicate rocks intercalated with meta-evaporites, and marbles. Tsavorite occurs either in nodules (also called “boudins”) oriented parallel to the metamorphic foliation in all of the deposits in the metamorphic belt or in quartz veins and lenses located at the hinges of anticlinal folds (Lelatema fold belt and Ruangwa deposits, Tanzania). Gem tanzanite occurs in pockets and lenses in the Lelatema fold belt of northern Tanzania. The Sm-Nd isotopic data for tsavorites and tanzanites hosted in quartz veins and lenses from Merelani demonstrate that they formed at 600 Ma, during the retrograde metamorphic episode associated with the East African Orogeny. The tsavorites hosted in nodules do not provide reliable ages: their sedimentary protoliths had heterogeneous compositions and their Sm-Nd system was not completely rehomogenized, even at the local scale, by the fluid-absent metamorphic recrystallization. The initial 87Sr/86Sr isotopic ratios of calcite from marble and tanzanites from Merelani fit with the strontium isotopic composition of Neoproterozoic marine carbonates. Seawater sediment deposition in the Mozambique Ocean took place around 720 Ma. The quartz-zoisite O-isotopic thermometer indicates a temperature of formation for zoisite between 385 and 448 °C. The sulfur isotopic composition of pyrite (between –7.8 and –1.3‰ V-CDT) associated with tsavorite in the Lelatema fold belt deposits suggests the contribution of reduced marine sulfate. The sulfur in pyrite in the marbles was likely derived from bacterial sulfate reduction which produced H2S. Fluid inclusion data from tsavorite and tanzanite samples from the Merelani mine indicate the presence of a dominant H2S-S8±(CH4)±(N2)±(H2O)-bearing fluid. In the deposits in Kenya and Madagascar, the replacement of sulfate by tsavorite in the nodules and the boron isotopic composition of tourmaline associated with tsavorite are strong arguments in favor of the participation of evaporites in garnet formation.
DS2000-0621
2000
Rakotondrazafy, R.Martelat, J.E., Lardeaux, J.M., Rakotondrazafy, R.Strain pattern and late Precambrian deformation history in southern MadagascarPrecambrian Research, Vol. 102, No. 1-2, July 1, pp. 1-20.MadagascarTectonics
DS1998-1477
1998
RakotosolofoTorsvik, T., Tucker, Ashwal, Eide, Rakotosolofo, De WitMadagascar: Cretaceous volcanism and the Marian hot spotJournal of African Earth Sciences, Vol. 27, 1A, p. 197. AbstractMadagascarvolcanism., Plume
DS1998-1204
1998
Rakotosolofo, N.A.Rakotosolofo, N.A., Torsvik, Ashwal, De Wit, EideMadagascar during the Late Paleozoic and MesozoicJournal of African Earth Sciences, Vol. 27, 1A, p. 148. AbstractMadagascarTectonics
DS2003-0937
2003
Rakovan, J.Meng, Y., Newville, M., Sutton, S., Rakovan, J., Mao, H-K.Fe and Ni impurities in synthetic diamondAmerican Mineralogist, Vol. 88, 10, Oct. pp. 1555-69.GlobalDiamond - synthesis
DS200412-1297
2003
Rakovan, J.Meng, Y., Newville, M., Sutton, S., Rakovan, J., Mao, H-K.Fe and Ni impurities in synthetic diamond.American Mineralogist, Vol. 88, 10, Oct. pp. 1555-69.TechnologyDiamond - synthesis
DS200812-0932
2008
Rakovan, J.Rakovan, J.Kimberlite - one of the best preserved dikes - and possible the first found - is currently located in a parking lot on Green Street in downtown Syracuse, N.Y.Rocks and Minerals, Vol. 83, May-June, p. 83-84.United States, New YorkHistory
DS1994-0134
1994
Raleigh, C.B.Behr, H.J., Raleigh, C.B.Crustal structure of the Bohemian Massif and the West CarpathiansSpringer, 372pEuropeBook -ad, Variscan Belt
DS1997-0943
1997
Ralfe, G.Ralfe, G.De Beers and the diamond industry: towards the new millenniumPreprint from De Beers, CSO, 5p. 5 slide viewsGlobalEconomics, CSO
DS2001-0961
2001
Ralfe, G.Ralfe, G.De Beers in the 21 st CenturyProspectors and Developers Association of Canada (PDAC) Luncheon address, March 12, Offprint of speech approx. 15p.GlobalNews item, De Beers
DS2001-0962
2001
Ralfe, G.Ralfe, G.De Beers in the 21st CenturyProspectors and Developers Association of Canada (PDAC) Luncheon address, March 12, Offprint of speech approx. 15p.GlobalNews item, De Beers
DS1991-1296
1991
Ralser, S.Park, A.F., Ralser, S.Structure of the early Proterozoic Hurwitz Group in the Tavani area, Keewatin, Northwest TerritoriesCanadian Journal of Earth Sciences, Vol. 28, No. 7, July pp. 1078-1095Northwest TerritoriesStructure, Proterozoic
DS1989-1250
1989
Ram Babu, H.V.Ram Babu, H.V., Atchuta Rao, D., et al.MAGTRAN: a computer program for the transformation of magnetic and gravityanomaliesComputers and Geosciences, Vol. 15, No. 6, pp. 979-988GlobalComputer, Program -MAGTRAN.
DS201508-0358
2015
Ram Moham, M.He, X-F., Santosh, M., Zhang, Z-M., Tsunogae, T., Chetty, T.R.K., Ram Moham, M., AnbazhaganShonkinites from Salem, southern India: implications for Cryogenian alkaline magmatism in rift related setting.Journal of Asian Earth Sciences, in press availableIndiaShonkinites
DS200412-1219
2004
Ram Mohan, M.Maniyamba, C., Kerrich, R., Naqvi, S.M., Ram Mohan, M.Geochemical systematics of tholeitic basalts from the 2.7 Ga Ramagiri Hungund composite greemstone belt, Dharwar Craton.Precambrian Research, Vol. 134, no. 1-2, Sept. 20, pp. 21-39.IndiaGeochronology - not specific to diamonds
DS200512-0681
2005
Ram Mohan, M.Manikyamba, C., Naqvi, S.M., Subba Rao, D.V., Ram Mohan, M., Khanna, T.C., Rao, T.G., Reddy, G.L.Boninites from the Neoarchean Gadwal greenstone belt, eastern Dharwar Craton, India, implications for Archean subduction processes.Earth and Planetary Science Letters, Vol. 230, 1-2, pp. 65-83.IndiaBoninites
DS201212-0578
2012
Ram Mohan, M.Ram Mohan, M., Singh, S.P., Santosh, M., Siddiqui, M.A., Balaram, V.TTG suite from the Bundelk hand Craton, Central India: geochemistry, petrogenesis and implications for Archean crustal evolution.Journal of Asian Earth Sciences, Vol. 58, pp. 38-50.IndiaTectonics
DS200512-1149
2003
Ram Mohan, V.Vladykin, N.V., Viladkar, S.G., Miyazaki, T., Ram Mohan, V.Chemical composition of carbonatites of Tamil Nadu massif ( South India) and problem of benstoonite carbonatites.Plumes and problems of deep sources of alkaline magmatism, pp. 130-154.IndiaCarbonatite, geochemistry
DS1998-1422
1998
Rama Brahman, G.Sundararajan, N., Rama Brahman, G.Spectral analysis of gravity anomalies caused by slab like structures: a Hartley Transform technique.Journal of Applied Geophys., Vol. 39, No. 1, May 10, pp. 53-65.MantleGeophysics - gravity, Slab - not specific to diamonds
DS1988-0581
1988
Rama Murthy, V.Roden, M.F., Irving, A.J., Rama Murthy, V.Isotopic and trace element composition of the upper mantle beneath a young continental rift: results from Kilbourne Hole,New MexicoGeochimica et Cosmochimica Acta, Vol. 52, No. 2, February pp. 461-474New MexicoBlank
DS1992-1250
1992
Rama Murthy, V.Rama Murthy, V., et al.Siderophile elements and the earth's formationScience, Vol. 257, August 28, pp. 1281-1285GlobalMantle, Siderophile elements -discussion
DS201112-0841
2011
Rama Rao, Ch.Rama Rao, Ch., Kishore, R.K., Kumar, R.P., Babu, B.B.Delineation of intra crustal horizon in Eastern Dharwar Craton - an aeromagntic evidence.Journal of Asian Earth Sciences, Vol. 40, 2, Jan. pp. 534-541.IndiaGeophysics - magnetics
DS200612-1226
2005
Rama Rao, G.Sastry, C.A., Rama Rao, G., Prasad, G.J.S., Reddy, V.A.Electro probe micro analysis of indicator minerals from kimberlites of Andhra Pradesh and Karnataka.Geological Survey of India, Bulletin, C6, 282p. Cited in GJSI. 67, 2, p. 280.India, Andhra Pradesh, KarnatakaGeochemistry
DS200812-0858
2008
Rama Rao, G.Patel, S.C., Ravi, S., Rao, C.R.M., Rama Rao, G., Nayak, S.S.Mineralogy and geochemistry of Wajrakaruru kimberlites, southen India.9IKC.com, 3p. extended abstractIndiaDeposit - Wajrakarur petrography
DS202010-1870
2020
Rama Rao, J.V.Rama Rao, J.V., Kumar, B.R., Kumar, M., Singh, R.B., Veeraich, B.Gravity of Dharwar craton, southern Indian shield.Journal of Geological Society of India, Vol. 96, 3, pp. 239-249. pdfIndiacraton

Abstract: Dharwar craton (DC), by far the largest geological domain in South Indian Shield, occupying about 0.5 million sq. km area, is well-studied terrain both for regional geoscientific aspects and as part of mineral exploration over several important blocks such as the greenstone belts, ultramafic complexes, granite-gneissic terrain and the Proterozoic sediments of Cuddapah basin. The re-look into regional gravity data offers several insights into nature of crust, sub-divisions within the craton, bedrock geology in the covered areas and mineral potentiality of this ancient and stable crust. The regional gravity profiles drawn across the south Indian region mainly suggest that the area can be divided into five domains as Western Dharwar craton (WDC), Central Dharwar craton (CDC), Eastern Dharwar craton (EDC 1), transitory zone of EDC (EDC 2) and Eastern Ghats mobile belt (EGMB) areas. The Bouguer gravity anomaly pattern also questions some of the earlier divisions like eastern margin of Chitradurga schist belt between the WDC and EDC and the boundary of DC with southern granulite terrain (SGT) as they do not restrict at these main boundaries. In this study, mainly four issues are addressed by qualitative and quantitative analysis of regional gravity data and those revealed significant inferences. (1) A distinct gravity character in central part of south Indian shield area occupying about 60, 000 sq. km, suggests that the transitory crustal block, faulted on both sides and uplifted. This area designated as central Dharwar craton (CDC) is characterized with schist belts having characters of both parts of western and eastern Dharwar craton. This inference also opens up the debate about the boundary between western and eastern parts of the craton. Another significant inference is the extension of major schist belts beneath both Deccan volcanic province (DVP) in northwestern part and Cuddapah basin (CB) in southeastern part. (2) Eastern Dharwar craton is reflected as two distinct domains of different gravity characters; one populated with number of circular gravity lows and a few linear gravity high closures indicative of plutonic and volcanic activity and another domain devoid of these intrusive younger granites or schist belts. (3) Large wave length gravity highs occupying thousands of sq.km area and those not relatable to surface geology in eastern Dharwar craton that may have significance for mineral exploration. (4) Gravity data was subjected to further processing like two dimensional modeling which have yielded insights into crustal architecture beneath the Dharwar craton, crustal scale lineaments, craton-mobile belt contact zone and younger intrusives.
DS200612-0875
2001
Ramachandra, H.M.Mathew, M.P., Ramachandra, H.M., Gouda, H.C., Singh, R.K., Acharya, G.R., Murthy, C.V.V.S., Rao, K.S.IGRF corrected regional aeromagnetic anomaly map of parts of Peninsular India - potential for mapping and mineral exploration.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 395-405.India, Andhra Pradesh, Karnataka, Tamil Nadu, KeralaGeophysics - magnetics
DS200612-1123
2005
Ramachandra, H.M.Ramachandra, H.M.Crustal evolution in Bastar Craton preceding kimberlite and related magmatism.Geological Society of India, Bangalore November Meeting Group Discussion on Kimberlites and Related Rocks India, Abstract p. 87-93.India, Bastar CratonTectonics
DS2003-0543
2003
Ramachandran, K.Hammer, P.T.C., Clowes, R.M., Ramachandran, K.Seismic reflection techniques for imaging Diamondiferous kimberlite dykes: a case studyGeological Association of Canada Annual Meeting, Abstract onlyNorthwest TerritoriesGeophysics - seismics
DS2003-0544
2003
Ramachandran, K.Hammer, P.T.C., Ramachandran, K., Clowes, R.M.Seismic imaging of thin, Diamondiferous kimberlite dykes8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractGlobalDiamond exploration - geophysics, seismics
DS200412-0774
2003
Ramachandran, K.Hammer, P.T.C., Clowes, R.M., Ramachandran, K.Seismic reflection techniques for imaging Diamondiferous kimberlite dykes: a case study from Snap Lake, N.W.T.Geological Association of Canada Annual Meeting, Abstract onlyCanada, Northwest TerritoriesGeophysics - seismics
DS200412-0775
2003
Ramachandran, K.Hammer, P.T.C., Ramachandran, K., Clowes, R.M.Seismic imaging of thin, Diamondiferous kimberlite dykes.8 IKC Program, Session 8, AbstractTechnologyDiamond exploration - geophysics, seismics
DS200512-0395
2004
Ramachandran, K.Hammer, P.T.C., Clowes, R.M., Ramachandran, K.High resolution seismic reflection imaging of a thin, Diamondiferous dyke.Geophysics, Vol. 69, 5, pp. 1143-1154.Canada, Northwest TerritoriesGeophysics - seismics, Snap Lake
DS201511-1877
2015
Ramachandran, K.T.Sastry, M.D., Mane, S., Gaonkar, M., Bhide, M.K., Desai, S.N., Ramachandran, K.T.Luminescence studies of gemstones and diamonds.International Journal of Luminescence and Applications, Vol. 5, 3, pp. 293-297.TechnologyLuminescence

Abstract: Some of the minerals like Corundum, chryso beryl, beryllium alumino silicate (emerald) and also Diamond exhibit exceptional optical properties[1] and in some cases attractive colours; in India these were recognized quite early since the days of Indus valley civilization. In more recent times there has been a lot of scientific interest in colours and colour modifications in Gem minerals and in Diamonds. Science of gem stones deals with their identification by non destructive means and understanding of origin of colour and excellent optical properties[1]. Optical methods have long been used to obtain properties like ‘Refractive Index’ which still remains an important parameter as a preliminary test to identify the gemstone/mineral. The spectroscopic studies of gem grade minerals are essentially directed towards some of these features in identifying and understanding the spectral properties of chromophores, either chemical impurities and/or radiation induced point defects, in solids. In this context a variety of spectroscopic methods are used to address the problems of the Gem stone identification and identification of origin of colours and colour modification treatments. The methods frequently used in Gem testing labs are the following: (i)Electronic absorption in UV-Visible-NIR range.(ii)UV-Vis excited luminescence, (iii) Vibrational spectra – Absorption in the Infra red range (iv) Vibrational spectra using Light Scattering (Raman spectroscopy) (v)Surface Fluorescence mapping Under deep UV excitation. The present paper deals with the luminescence studies in rubies, sapphires, emeralds and diamonds. Special mention may be made of fluorescence mapping using deep UV excitation (around 205 nm) corresponding to the band gap of diamond. Under such an excitation inter band excitation takes place creating a e-h pair and most of the absorption and subsequent emission being restricted to the surface. This makes surface mapping possible and thereby elucidating the growth patterns. This is invaluable in the diagnostics for the detection of synthetic diamonds. In this introductory presentation on the Luminescence methods in Gemmology, we give a brief account of optical spectroscopic methods which mainly deal with identification of corundum based gem stones (rubies, sapphire) and diamonds including the electronic absorption and luminescence of chromophore centres. In gem testing infrared absorption and Raman scattering methods are main work horses and they will be brought in as and when necessary to give a complete picture.
DS2002-1301
2002
Ramadass, G.Ramadass, G., Ramaprasada Rao, I.B., Himanbindu, D., Srinivasulu, N.Psuedo surface velocities ( densities) and pseudo depth densities ( velocities) along selected profiles in the Dharwar Craton, India.Current Science, Vol. 82,No. 2, Jan. 25, pp. 197-201.IndiaGeophysics - seismics
DS2002-1302
2002
Ramadass, G.Ramadass, G., Rao, I.B.R., Himabindu, D., SrinivasuluPseudo surface velocities (densities) and pseudo depth densities along profiles Dharwar Craton, India.Current Science, Vol.82,No.2, pp. 197-201.IndiaGeophysics - seismics, Craton - Dharwar
DS2003-1126
2003
Ramadass, G.Ramadass, G., Rao, I.B.R., Srinivasulu, N., Himabindu, D.Density studies in the Dharwar Craton along the Jadcharla Goa subtransectJournal Geological Society of India, Vol. 61, 4, pp. 439-448.IndiaGeophysics - seismics
DS200412-1615
2003
Ramadass, G.Ramadass, G., Rao, I.B.R., Srinivasulu, N., Himabindu, D.Density studies in the Dharwar Craton along the Jadcharla Goa subtransect.Journal Geological Society of India, Vol. 61, 4, pp. 439-448.IndiaGeophysics - seismics
DS200512-0888
2005
Ramadass, G.Ramadass, G., Rao, I.B.R., Himabindu, D.Regional appraisal from gravity investigations in the Dharwar Craton: Jadcharla - Goa transect.Journal of the Geological Society of India, Vol. 65, 1, pp. 61-69.IndiaGeophysics - gravity not specific to diamonds
DS200612-1124
2006
Ramadass, G.Ramadass, G., Ramaprasada Rao, I.B., Himnindu, D.Crustal configuration of the Dhawar Craton, India: based on joint modelling of regional gravity and magnetic data.Journal of Asian Earth Sciences, Vol. 26, 5, pp. 437-448.Asia, IndiaGeophysics - gravity, magnetics
DS200912-0792
2009
Ramadass, G.Veeraiah, B., Ramadass, G., Himabindu, D.A subsurface criterion for predictive exploration of kimberlites from bouguer gravity in the eastern Dharwar craton, India.Journal of the Geological Society of India, Vol. 74, July pp. 69-77.IndiaMaddur-Narayanpet kimberlite, geophysics
DS201112-1084
2009
Ramadass, G.Veeraiah, B., Ramadass, G., Himabindu, D.A subsurface criterion for predictive exploration of kimberlites from Bouguer Gravity in the eastern Dharwa craton, India.Journal of the Geological Society of India, Vol. 74, pp. 69-77.IndiaNarayanpet-Irladinne area
DS201612-2319
2016
Ramakokovhu, M.M.Mahlangu, T., Moemise, N., Ramakokovhu, M.M., Olubambi, P.A., Shongwe, M.B.Seperation of kimberlite from waste rocks using sensor-based sorting at Culli nan diamond mine.Journal of South African Institute of Mining and Metallurgy, Vol. 116, Apr. pp. 343-348.Africa, South AfricaDeposit - Cullinan

Abstract: Near-infrared (NIR) spectroscopy sorting technology is incorporated in an automated optical mineral sorter that can discriminate between materials using the differences in characteristics when exposed to near-infrared radiation. During September 2014 to April 2015, a pilot plant that utilized NIR technology to discriminate between kimberlite and waste materials was commissioned to determine the viability of including this technology in the diamond winning process flow sheet at Cullinan Diamond Mine. The plant was used to minimize the waste content in the size fraction -70+35 mm that reports to the crushing section and then to the dense media separation process. This paper describes the initial test work, conducted at Mintek, that led to the decision to conduct a pilot-scale study. The mineralogical characterization of the feed and product streams to establish the sorting criteria and the operational data obtained during the pilot plant campaign are described. The results indicated a good possibility of discriminating between the kimberlite and waste material using NIR technology. However, the consistency of discrimination was not good enough to avoid the risk of potential diamond loss. Furthermore, a lower than expected availability of the machine reduced the throughput capabilities.
DS201709-2028
2016
Ramakokovhu, M.M.Mahlangau, T., Moemise, N., Ramakokovhu, M.M., Olubambi, P.A., Shongwe, M.B.Separation of kimberlite from waste rocks using sensor based sorting at Culli nan diamond mine.South African Institute of Mining and Metallurgy, Vol. 116, 4, pp. 343-350.Africa, South Africadeposit - Cullinan

Abstract: Near-infrared (NIR) spectroscopy sorting technology is incorporated in an automated optical mineral sorter that can discriminate between materials using the differences in characteristics when exposed to near-infrared radiation. During September 2014 to April 2015, a pilot plant that utilized NIR technology to discriminate between kimberlite and waste materials was commissioned to determine the viability of including this technology in the diamond winning process flow sheet at Cullinan Diamond Mine. The plant was used to minimize the waste content in the size fraction -70+35 mm that reports to the crushing section and then to the dense media separation process. This paper describes the initial test work, conducted at Mintek, that led to the decision to conduct a pilot-scale study. The mineralogical characterization of the feed and product streams to establish the sorting criteria and the operational data obtained during the pilot plant campaign are described. The results indicated a good possibility of discriminating between the kimberlite and waste material using NIR technology. However, the consistency of discrimination was not good enough to avoid the risk of potential diamond loss. Furthermore, a lower than expected availability of the machine reduced the throughput capabilities.
DS200412-1616
2004
Ramakrishnan, M.Ramakrishnan, M.Advances in the Precambrian of central India.Journal of Geological Society of India, Vol. 63, 2, pp. 239-242.IndiaGeology - regional
DS200912-0611
2009
Ramakrishnan, M.Ramakrishnan, M.Precambrian mafic magmatism in the western Dharwar Craton, southern India.Journal of the Geological Society of India, Vol. 73, 1, pp. 101-116.IndiaMagmatism
DS1985-0133
1985
Ramakrishnan, S.Cullers, R.L., Ramakrishnan, S., Berendsen, P., Griffin, T.Geochemistry and Petrogenesis of Lamproites, Late Cretaceous Age, Woodson County, Kansas, United States (us)Geochimica et Cosmochimica Acta ., Vol. 49, PP. 1383-1402.United States, Central States, KansasLamproite Terminology, Analyses, Silver City Dome
DS201212-0750
2012
Ramakrishnarao, M.V.Vani, T., Haga Laksmi, V., Ramakrishnarao, M.V., Kelly, G.R., Subbarao, K.V.Integration of geophsyical and geological dat a of kimberlites in Narayayanapet - Maddur field, Andhra Pradesh, India.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractIndia, Andhra PradeshDeposit - Narayayanapet-Maddur
DS201412-0941
2013
Ramakrishnarao, M.V.Vani, T., Lakshimi, V.N., Ramakrishnarao, M.V., Keller, G.R., Subbarao, K.V.Integration of geophysical and geological dat a of kimberlites in Narayanpet-Maddur field, Andhra Pradesh, India.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 229-240.India, Andhra PradeshDeposit - Narayanpet- Maddur
DS202005-0761
2019
Ramakrsihna Reddy, N.Singh, T.D., Manikyamba, C., Subramanyam, K.S.V., Ganguly, S., Khelen, A., Ramakrsihna Reddy, N.Mantle heterogeneity, plume-lithosphere interaction at rift controlled ocean-continent transition zone: evidence from trace PGE geochemistry of Vempalle flows, Cuddapah basin India.Geoscience Frontiers, in press, 20p. PdfIndiaREE

Abstract: This study reports major, trace, rare earth and platinum group element compositions of lava flows from the Vempalle Formation of Cuddapah Basin through an integrated petrological and geochemical approach to address mantle conditions, magma generation processes and tectonic regimes involved in their formation. Six flows have been identified on the basis of morphological features and systematic three-tier arrangement of vesicular-entablature-colonnade zones. Petrographically, the studied flows are porphyritic basalts with plagioclase and clinopyroxene representing dominant phenocrystal phases. Major and trace element characteristics reflect moderate magmatic differentiation and fractional crystallization of tholeiitic magmas. Chondrite-normalized REE patterns corroborate pronounced LREE/HREE fractionation with LREE enrichment over MREE and HREE. Primitive mantle normalized trace element abundances are marked by LILE-LREE enrichment with relative HFSE depletion collectively conforming to intraplate magmatism with contributions from sub-continental lithospheric mantle (SCLM) and extensive melt-crust interaction. PGE compositions of Vempalle lavas attest to early sulphur-saturated nature of magmas with pronounced sulphide fractionation, while PPGE enrichment over IPGE and higher Pd/Ir ratios accord to the role of a metasomatized lithospheric mantle in the genesis of the lava flows. HFSE-REE-PGE systematics invoke heterogeneous mantle sources comprising depleted asthenospheric MORB type components combined with plume type melts. HFSE-REE variations account for polybaric melting at variable depths ranging from garnet to spinel lherzolite compositional domains of mantle. Intraplate tectonic setting for the Vempalle flows with P-MORB affinity is further substantiated by (i) their origin from a rising mantle plume trapping depleted asthenospheric MORB mantle during ascent, (ii) interaction between plume-derived melts and SCLM, (iii) their rift-controlled intrabasinal emplacement through Archean-Proterozoic cratonic blocks in a subduction-unrelated ocean-continent transition zone (OCTZ). The present study is significant in light of the evolution of Cuddapah basin in the global tectonic framework in terms of its association with Antarctica, plume incubation, lithospheric melting and thinning, asthenospheric infiltration collectively affecting the rifted margin of eastern Dharwar Craton and serving as precursors to supercontinent disintegration.
DS1975-0387
1976
RamalingaswanyRamalingaswanyOn the Possibility of Kimberlite Dyke in Giddalur AreaIndia Geological Survey, UNPUBL.India, Andhra PradeshBlank
DS1999-0578
1999
Ramam, P.K.Ramam, P.K.Mineral resources of Andhra Pradesh.Kimberlites - lamproites pp. 11-13.Diamonds pp. 114-32.Geological Society India, 253p.India, Andhra PradeshDiamonds - Wajrakaruru, Maddur-Kotakonda, QPC Banganapaale, Narayanpet, Mahboobnagar
DS1940-0057
1942
Raman, C.V.Raman, C.V.The Physics of the DiamondCurrent Science., Vol. 11, No. 7, PP.IndiaCrystallography, Morphology, Natural Diamond
DS1940-0127
1946
Raman, C.V.Raman, C.V., Ramashesham, S.The Crystal Forms of Diamond and their SignificanceIndian Academy of Science Proceedings, Vol. 24, No. 1, PP.IndiaCrystallography, Diamond, Morphology, Natural Diamond
DS1950-0039
1950
Raman, C.V.Raman, C.V., Jayaraman, A.The Luminescence of Diamond and its Relation to Crystal Structure.Indian Academy of Science Proceedings, Vol. 32, SECT. A, No. 2IndiaCrystallography
DS1950-0294
1956
Raman, C.V.Raman, C.V.The Diamond (1956)Indian Academy of Science Proceedings, Vol. 44, SECT. A, No. 3, PP. 99-110.IndiaCrystallography, Mineralogy
DS1950-0295
1956
Raman, C.V.Raman, C.V.The Specific Heat of Crystals. Pt. 1. Grand Theory. Pt. 2. The Case of Diamond.Indian Academy of Science Proceedings, Vol. 44, SECT. A, No. 4, PP. 153-164.IndiaCrystallography, Mineralogy
DS1950-0349
1957
Raman, C.V.Raman, C.V.The Heat Capacity of Diamond Between 0 K and 1000 KIndian Academy of Science Proceedings, Vol. 46, SECT. A, No. 5, PP. 323-332.IndiaCrystallography
DS1950-0423
1958
Raman, C.V.Raman, C.V.The Diffraction of X-rays by Diamond. Pt. 2Indian Academy of Science Proceedings, Vol. 47, SECT. A, No. 6, PP. 335-343.IndiaCrystallography, Mineralogy
DS1960-1196
1969
Raman, C.V.Raman, C.V.The Diamond (1969)Unknown, 246P.GlobalPhysics, Infrared, Luminescence, Morphology
DS1960-1010
1968
Raman, G.V.Raman, G.V.The Diamonds of the Krishna ValleyCurrent Science., Vol. 37, No. 19, PP. 541-542.India, Andhra PradeshDiamond Occurrences
DS1987-0397
1987
Ramana, Y.V.Lastovickova, M., Ramana, Y.V., Gogte, B.S.Electrical conductivity of some rocks from the Indian subcontinentStudies Geophysics Geody, Vol.31, No. 1 pp. 60-72IndiaGeophysics, Kimberlite
DS1987-0262
1987
Ramana Rao, A.V.Guptasarma, D., Chetty, T.R.K., Murthy, D.S.N., Ramana Rao, A.V.Case history of a kimberlite discovery, Wajrakarur area, Andhra IndiaExploration 87, technical abstract volume, held Toronto Sept. 2 27-Oct, p. 25. abstract onlyIndiaGeomorphology, Indicator minerals
DS1988-0277
1988
Ramana Rao, A.V.Guptasarma, D., Chetty, T.R.K., Murthy, D.S.N., Ramana Rao, A.V.Case history of a kimberlite discovery, Wajrakaur area, A.P.,SouthIndiaExploration 87, Proceedings Volume, Ontario Geological Survey, Special Publishing No. 3, pp. 888-897IndiaGeophysics
DS1988-0561
1988
Ramananantoandro, R.Ramananantoandro, R.Seismic evidence for mantle flow beneath the Massif Central rift zone, France.Canadian Journal of Earth Sciences, Vol. 25, pp. 2139-42.FranceGeophysics - seismic, Rifting
DS1994-1428
1994
Ramani, R.J.Ramani, R.J., Mozumdar, B.K., Samaddar, A.B.Computers in mineral industryA.a.balkema, 350pGlobalEconomics, evaluation, geostatistics, ore reserves, Book -table of contents
DS200512-0522
2004
Ramanko, E.F.Kharkiv, A.D., Ramanko, E.F., Zubarev, B.M.Kimberlites of Zimbabwe: abundance and composition.Russian Geology and Geophysics, Vol. 45, 3, pp. 317-327.Africa, ZimbabweOverview
DS1994-1429
1994
Ramanowiez, B.Ramanowiez, B.An elastic tomography: a new perspective on upper mantle thermal structureEarth Planetary Science Letters, Vol. 128, No. 3-4, Dec. pp. 113-122.MantleTomography
DS2002-1301
2002
Ramaprasada Rao, I.B.Ramadass, G., Ramaprasada Rao, I.B., Himanbindu, D., Srinivasulu, N.Psuedo surface velocities ( densities) and pseudo depth densities ( velocities) along selected profiles in the Dharwar Craton, India.Current Science, Vol. 82,No. 2, Jan. 25, pp. 197-201.IndiaGeophysics - seismics
DS200612-1124
2006
Ramaprasada Rao, I.B.Ramadass, G., Ramaprasada Rao, I.B., Himnindu, D.Crustal configuration of the Dhawar Craton, India: based on joint modelling of regional gravity and magnetic data.Journal of Asian Earth Sciences, Vol. 26, 5, pp. 437-448.Asia, IndiaGeophysics - gravity, magnetics
DS1991-1395
1991
Ramarao, Ch.Ramarao, Ch., Chetty, T.R.K., Lingaiah, A., Babu Rao, V.Delineation of a greenstone belt using aeromagnetics, Land sat and photogeology - a case study from the South Indian ShieldGeoexploration, Vol. 28, pp. 121-137IndiaRemote sensing, Geophysics -magnetics, linements
DS201607-1374
2016
Ramarao, J.Ramarao, J.Gravity anomalies over Indian cratons and their geological implications.IGC 35th., Session The Deep Earth 1 p. abstractIndiaGeophysics - gravity
DS1960-0291
1962
Ramarathnam, S.Ramarathnam, S.Geology and Petrology of the Southern Portion of the Laramie Anorthosite Massif, Albany County, Wyoming.Golden: Ph.d. Thesis, Colorado School Mines, 131P.United States, Wyoming, Rocky MountainsRegional Studies
DS2000-0374
2000
RamasamyGwalani, L.G., Rock, N.M.S., Ramasamy, Griffin, MulaiComplexly zoned Ti rich melanite schorlomite garnets from Ambadungar carbonatite alkalic complex, DeccanJournal of Asian Earth Science, Vol. 18, No.2, Apr. pp.163-76.India, Gujarat, WesternCarbonatite, Deposit - Ambadungar
DS2002-1209
2002
Ramasamy, A.K.Pandit, M.K., Sial, A.N., Sukumaran, G.B., Pimentel, M.M., Ramasamy, A.K.Depleted and enriched mantle sources for Paleo- and Neoproterozoic carbonatites ofChemical Geology, Vol. 189,1-2,pp. 69-89.India, Tamil NaduCarbonatite - geochronology, Deposit - Samalpatti, Sevattur, Mulakkasu
DS1980-0284
1980
Ramasamy, R.Ramasamy, R.Tectonomagmatic Evolution of Carbonatite Complex of Tiruppattur, India.Proceedings of the 26th International Geological Congress, Vol. 1, SECT. 5 P. 80. (abstract.).India, Tamil NaduCarbonatite, Related Rocks
DS1980-0285
1980
Ramasamy, R.Ramasamy, R., Shapenko, V.Fluid Inclusion Studies in Carbonatites of Tiruppattur, IndiProceedings of the 26th International Geological Congress, Vol. 1, SECT. 5 P. 79. (abstract.).India, Tamil NaduCarbonatite, Related Rocks, Isotope
DS1982-0514
1982
Ramasamy, R.Ramasamy, R.The Supposed Eastern Ghats Paleorift Zone on the Indian Subcontinent.Moscow University Bulletin., Vol. 37, No. 2, PP. 31-36.IndiaCarbonatite, Tectonics, Rifting, Related Rocks
DS1986-0661
1986
Ramasamy, R.Ramasamy, R.Calcium rich pyroxenes from the carbonatite complex of Tiruppatur, Tamil NaduCurrent Science, Vol. 55, No. 20, pp. 981-984IndiaCarbonatite
DS1992-1251
1992
Ramasamy, R.Ramasamy, R.Carbonatite-apatite from carbonatites of Kudangulam near Cape Comorin, Tamilnadu.Indian Minerals, Vol. 46, No. 1, January-March pp. 91-94.IndiaCarbonatite
DS1995-1539
1995
Ramasamy, R.Ramasamy, R.Effects of metasomatism on the country rocks around carbonatites of Kudangulam area, Tamil Nadu.Journal of Geological Society India, Vol. 46, No. 2, August pp. 117-124.IndiaCarbonatite
DS1995-1659
1995
Ramasamy, R.Saravanan, S., Ramasamy, R.Geochemistry and petrogenesis of shonkinite and associated alkaline Rocks of Tiruppattur carbonatite complex.Journal of Geological Society India, Vol. 46, No. 3, Sept. pp. 235-244.IndiaCarbonatite, Deposit -Tiruppattur
DS1997-0944
1997
Ramasamy, R.Ramasamy, R., Gwalani, L.G., Randive, K.R., Mulai, B.P.Geology of the Indian carbonatites and evolution of alkali carbonatite magma in peninsular India.Geological Association of Canada (GAC) Abstracts, POSTER.IndiaCarbonatite
DS2000-0792
2000
Ramasamy, R.Ramasamy, R., Gwalani, L.G., Pandit, M.K.Geology of Indian carbonatites and evolution of alkali carbonatite magmaIgc 30th. Brasil, Aug. abstract only 1p.IndiaTectonics - rifting, Carbonatite
DS2001-0963
2001
Ramasamy, R.Ramasamy, R., Gwalani, L.G., Subramanian, S.P.A note on the occurrence and formation of magnetite in the carbonatites ofSevvattur, North Arcot Tamil Nadu.Journal of African Earth Sciences, Vol. 19, No. 3, Apr. pp.297-304.India, Tamil NaduCarbonatite, Mineralogy
DS1995-1540
1995
Ramasamy, S.M.Ramasamy, S.M., Balaji, S.Remote sensing and Pleistocene tectonics of Southern Indian peninsulaInternational Journal of Remote Sensing, Vol. 16, No. 13, Sept. 10, pp. 2375-2392IndiaTectonics, Remote sensing
DS200512-0057
2005
Ramasamy, S.M.Balaji, S., Ramasamy, S.M.Remote sensing and resistivity image for the tectonic analysis of Biligirirangan region, peninsular India.Geocarto International, Vol. 20, 2, pp. 55-62.Asia, IndiaRemote sensing
DS200712-0867
2006
Ramasamy, S.M.Ramasamy, S.M.Remote sensing and active tectonics of South India.International Journal of Remote Sensing, Vol. 27, 20, pp. 4397-4431.IndiaTectonics
DS201511-1863
2015
Ramasar, V.Meissner, R., Ramasar, V.Governance and politics in the upper Limpopo River basin, South Africa.Geojournal, Vol. 80, 5, pp. 689-709.Africa, South AfricaMentions Venetia

Abstract: Everyday international political economy (EIPE) offers an opportunity to rethink the role of individuals and citizenry in shaping governance of natural resources. In South Africa, significant progress has been made by government in re-shaping water governance since the end of apartheid in the early 1990s. The role of government in water governance and water politics has thus been emphasised to a large degree. This study looks at historical material to assess the role that water politics and EIPE has played in shaping the use and management of water resources in the country. Case studies are analysed of two quaternary catchments, A63E and A71L in the Limpopo River Basin, to show how everyday actions by different actors has shaped the current waterscape in the basin. Four events, namely, the politics of the Middle Iron Age State at Mapungubwe; the development of the Mapungubwe National Park and World Heritage Site; the management of water for the De Beers Venetia Diamond Mine; and the establishment of the Coal of Africa Limited colliery are discussed in terms of the agential power at play during each event. The conclusions of the study are that EIPE and reflexive agential power are important factors in water governance that can sometimes be ignored through neoliberal institutionalism. In the current and future governance of water in South Africa they can offer an alternative view of the role and importance of actors and pathways for development.
DS1940-0127
1946
Ramashesham, S.Raman, C.V., Ramashesham, S.The Crystal Forms of Diamond and their SignificanceIndian Academy of Science Proceedings, Vol. 24, No. 1, PP.IndiaCrystallography, Diamond, Morphology, Natural Diamond
DS1996-1154
1996
Ramassamy, R.Ramassamy, R.Carbonatite dykes from Kudangulam area, near Cape Comorin, Tamil NaduJournal of Geological Society India, Vol. 48, No. 2, Aug. 1, pp. 221-IndiaCarbonatite
DS1984-0602
1984
Ramaswamy, R.Ramaswamy, R.Vogesite from Carbonatite Complex of Tiruppattur, Tamil Nadu India.Geological Society INDIA Journal, Vol. 25, No. 5, PP. 307-310.India, Tamil NaduMineralogy
DS1960-0634
1966
Ramberg, I.B.Barth, T.F.W., Ramberg, I.B.The Fen Circular ComplexWiley Interscience Publishing, PP. 225-257.Norway, ScandinaviaCarbonatite, Geology, Petrography
DS1970-0810
1973
Ramberg, I.B.Ramberg, I.B.Gravity Studies of the Fen Complex, Norway and Their Petrological Significance.Contributions to Mineralogy and Petrology, Vol. 38, PP. 115-134.Norway, ScandinaviaPetrology
DS201801-0050
2017
Rambolamanana, G.Pratt, M.J., Wysession, M.E., Aleqabi, G., Wiens, D.A., Nyblade, A., Shore, P., Rambolamanana, G., Andriampenomanana, F., Rakotondraibe, T., Tucker, R.D., Barruol, G., Rindraharisaona, E.Shear velocity structure of the crust and upper mantle of Madagascar derived from surface wave tomography.Earth and Planetary Science Letters, Vol. 458, 1, pp.405-417.Africa, Madagascargeophysics - seismics

Abstract: The crust and upper mantle of the Madagascar continental fragment remained largely unexplored until a series of recent broadband seismic experiments. An island-wide deployment of broadband seismic instruments has allowed the first study of phase velocity variations, derived from surface waves, across the entire island. Late Cenozoic alkaline intraplate volcanism has occurred in three separate regions of Madagascar (north, central and southwest), with the north and central volcanism active until <1 Ma, but the sources of which remains uncertain. Combined analysis of three complementary surface wave methods (ambient noise, Rayleigh wave cross-correlations, and two-plane-wave) illuminate the upper mantle down to depths of 150 km. The phase-velocity measurements from the three methods for periods of 8-182 s are combined at each node and interpolated to generate the first 3-D shear-velocity model for sub-Madagascar velocity structure. Shallow (upper 10 km) low-shear-velocity regions correlate well with sedimentary basins along the west coast. Upper mantle low-shear-velocity zones that extend to at least 150 km deep underlie the north and central regions of recent alkali magmatism. These anomalies appear distinct at depths <100 km, suggesting that any connection between the zones lies at depths greater than the resolution of surface-wave tomography. An additional low-shear velocity anomaly is also identified at depths 50-150 km beneath the southwest region of intraplate volcanism. We interpret these three low-velocity regions as upwelling asthenosphere beneath the island, producing high-elevation topography and relatively low-volume magmatism.
DS1860-0115
1870
Rambosson, J.Rambosson, J.Les Pierres Precieuses et les Principaux OrnamentsParis: Librairie De Firmin Didot Freres File Et Cie., 298P.GlobalGemology
DS2002-0894
2002
Ramboz, C.Kouzmanov, K., Bailly, L., Ramboz, C., Rouer, O., BnyMorphology, origin and infrared microthermometry of fluid inclusions in pyrite from Radka epithermal copperMineralium deposita, BulgariaCopper, gold, geochronology, Deposit - Radka, Srednogorie zone
DS1994-1430
1994
Ramchnadran, K.T.Ramchnadran, K.T., Porwal, B.Famous diamonds... mainly Indian... listed with weight and shape .. briefhistory.Indian Gemologist, Vol. 4, No. 1, pp. 20-3.GlobalHistory, Famous diamonds, diamonds notable
DS1970-0194
1970
Ramdas, A.K.Solin, S.A., Ramdas, A.K.Raman Spectrum of DiamondPhys. Rev. B., Vol. 1, No. 4, Feb. 15, pp. 1687-1698GlobalSpectroscopy, Diamond Morphology
DS1994-1431
1994
Ramdas, A.K.Ramdas, A.K.Vibrational band structure of diamondProperties and growth of diamond, G. Davies, pp. 13-22.GlobalDiamond, Bulk properties of natural isotope diamond
DS1983-0230
1983
Ramenskaya.Florovskaya, V.N., Korytov, F.YA., Ogloblina, A.I., Ramenskaya.Polycycle Aromatics in a Plutonic Lherzolite Xenolith and BasaltDoklady Academy of Science USSR, Earth Science Section., Vol. 262, No. 106, PP. 121-122.Russia, MongoliaRelated Rocks
DS201212-0791
2012
Rameseder, B.Wood, B.D., Rameseder, B., Scott Smith, B.H.The Victor diamond mine, northern Ontario Canada: successful mining of a reliable resource.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractCanada, Ontario, AttawapiskatDeposit - Victor
DS201312-0982
2013
Rameseder, B.Wood, B.D., Scott Smith, B.H., Rameseder, B.The Victor diamond mine, northern Ontario, Canada: successful mining of a reliable resource.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, Special Issue of the Journal of the Geological Society of India,, Vol. 2, pp. 19-33.Canada, Ontario, AttawapiskatDeposit - Victor
DS201412-0988
2013
Rameseder, B.Wood, B.D., Scott Smith, B.H., Rameseder, B.The Victor diamond mine, northern Ontario, Canada: successful mining of a reliable resource.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 19-34.Canada, Ontario, AttawapiskatDeposit - Victor
DS1989-1442
1989
Ramesh, D.S.Sringesh, D., Rai, S.S., Ramesh, D.S., Gaur, V.K., Rao, C.V.R.Evidence for thick continental roots beneath South Indian shieldGeophysical Research Letters, Vol. 16, No. 9, September pp. 1055-1058IndiaMantle
DS1996-0788
1996
Ramesh, D.S.Krisna, V.G., Ramesh, D.S.A discussion on 410 km depth discontinuity: a sharpness estimate for near vertical reflection Vidale.Geophysical research Letters, Vol. 23, No. 18, Sept. 1, pp. 2573-MantleGeophysics -seismics, Discontinuity
DS2002-0905
2002
Ramesh, D.S.Kumar, M.R., Ramesh, D.S., Saul, J., Sarker, D., Kind, R.Crustal structure and upper mantle stratigraphy of the Arabian ShieldGeophysical Research Letters, Vol. 89, No. 8, April 15, pp. 83-Arabian Shield, North AfricaTectonics
DS2002-1303
2002
Ramesh, D.S.Ramesh, D.S., Kind, R., Yuan, X.Receiver function analysis of the North American crust and upper mantleGeophysical Journal International, Vol.150,1,pp.91-108.MantleGeophysics - seismics
DS2003-0812
2003
Ramesh, D.S.Li, X., Kind, R., Yuan, X., Sobolev, S.V., Hanka, W., Ramesh, D.S., Gu, Y.Seismic observation of narrow plumes in the oceanic upper mantleGeophysical Research Letters, Vol. 30, 6, p. 67. DOI10.1029/2002GLO15411MantlePlumes
DS200412-1130
2003
Ramesh, D.S.Li, X., Kind, R., Yuan, X., Sobolev, S.V., Hanka, W., Ramesh, D.S., Gu, Y., Dziewonski, A.M.Seismic observation of narrow plumes in the oceanic upper mantle.Geophysical Research Letters, Vol. 30, 6, p. 67. DOI10.1029/2002 GLO15411MantleGeophysics - seismics Plumes
DS200512-0588
2004
Ramesh, D.S.Kumar, M.R., Raju, P.S., Devi, E.U., Saul, J., Ramesh, D.S.Crustal structure variations in northeast India from converted phases.Geophysical Research Letters, Vol. 31, 17, Sept. 16, L17605IndiaTectonics
DS200512-0889
2005
Ramesh, D.S.Ramesh, D.S., Kumar, M.R., Devi, E.U., Raju, P.S., Yaun, X.Moho geometry and upper mantle images of northeast India.Geophysical Research Letters, Vol. 32, 14, July 28, L14301IndiaGeophysics - seismics
DS200612-1312
2006
Ramesh, D.S.Singh, A., Kumar, M.R., Raju, P.S., Ramesh, D.S.Shear wave anisotropy of the northeast Indian lithosphere.Geophysical Research Letters, Vol. 33, 16, August 28, L16302.IndiaGeophysics - seismics
DS201012-0137
2010
Ramesh, D.S.Das Sharma, S., Ramesh, D.S., Li, X., Yuan, B., Sreenivas, B., Kind, R.Response of mantle transition zone thickness to plume bouyancy flux.Geophysical Journal International, Vol. 180, 1, pp. 49-58.MantlePlume
DS201312-0184
2013
Ramesh, D.S.Das Sharma, Ramesh, D.S.Imaging mantle lithosphere for diamond prospecting in southeast India.Lithosphere, Vol. 5, no. 4, pp. 331-342.IndiaTectonics
DS1999-0586
1999
Ramesh, R.Ray, J.S., Ramesh, R., Pande, K.Carbon isotopes in Kerguelen plume derived carbonatites: evidence for recycled inorganic carbon.Earth and Planetary Science Letters, Vol. 170, No. 3, July 15, pp. 205-14.GlobalCarbonatite, Carbon cycle
DS2000-0802
2000
Ramesh, R.Ray, J.S., Ramesh, R., Pande, Trivedi, Shukla, PatelIsotope and rare earth element chemistry of carbonatite alkaline complexes of Deccan volcanic: implications...Journal of Asian Earth Science, Vol. 18, No.2, Apr. pp.177-94.India, Gujarat, WesternCarbonatite, Magmatism, alteration
DS200512-1141
2005
Ramesh, R.Viladkar, S.G., Ramesh, R., Avasia, R.K., Pawaskar, P.B.Extrusive phase of carbonatite alkalic activity in Amba Dongar Complex, Chhota Udaipur Gujarat.Journal of the Geological Society of India, Vol. 66, 3, pp. 273-276.IndiaCarbonatite
DS200612-1138
2006
Ramesh, R.Ray, J., Ramesh, R.Stable carbon and oxygen isotopic compositions of Indian carbonatites.International Geology Review, Vol. 48, 1, Jan. pp. 17-45.IndiaGeochronology
DS1991-0117
1991
Ramesh Babu, N.Bhaskara Rao, D., Ramesh Babu, N.A FORTRAN-77 computer program for three dimensional analysis of gravity anomalies with variable density contrastComputers and Geosciences, Vol. 17, No. 5, pp. 655-668GlobalComputer, Program -gravity
DS202003-0358
2019
Rameshchandra Phani, P.Rameshchandra Phani, P.Restoring the past glory of diamond mining in south India - A plausible case of diamondiferous Wajrakarur kimberlite pipe clusters with geochemical evidences.International Journal of Mining and Geo-Engineering, 11p. PdfIndiadeposit - Wajrakarur

Abstract: A plausible case of collective and economical mining of diamondiferous kimberlite deposits of Wajrakarur and adjoining places in Andhra Pradesh, southern India along with the whole-rock geochemical evidences in support of their diamond potentiality are discussed in this article. The kimberlites/lamproites are mantle-derived ultrabasic rocks which rarely carry diamonds from mantle to the earth’s surface through carrot-shaped intrusions referred to as pipes. Even though few hundreds of diamondiferous kimberlite pipes were discovered in India so far, there is no other production unit than Panna diamond mine in the country where primary rock is mined. In ancient India, diamond mining in south India in the Krishna river valley was well-known to the world fascinated by famous gemstones like Koh-I-Noor, Hope, Darya-e-Noor, Noor-ul-ain etc. which were mainly extracted from alluvium or colluvium in Krishna river valley. Having bestowed with more than 45 kimberlite pipes, the Wajrakarur kimberlite field (WKF) forms a favourable region for initiating diamond mining in the country. Geochemically, majority of the WKF show low TiO2 content and considerably high diamond grade (DG) values (>3) except some pipes viz., P-5 (Muligiripalli), P-13 (Tummatapalli) and P-16 (Pennahobilam) are barren due to high TiO2 and ilmenite contents. The TiO2 content (0.66-6.62 wt%) is inversely proportional to the DG (3.33 to 22.13). The DG value of some of the WKF pipes is close to that of Panna (8.36). The cationic weight% values clearly portray the diamondiferous nature of these deposits. The WKF pipes were also proved to be diamondiferous by exploratory drilling and bulk sample processing results by the government organisations. In southern India, due to several reasons, diamond mining has not seen its initiation and impetus till now although it records a considerable number of fertile kimberlite pipes at Wajrakarur, Lattavaram, Chigicherla, Timmasamudram etc. Though the majority of WKF diamondiferous kimberlite deposits in Wajrakarur are small in their areal extent (0.06-4.48 Ha) some of them are large (>10 Ha up to 120 ha). They occur in close proximity to each other offering feasibility for collective mining and winning the precious stone through a central processing unit by deploying the latest processing technologies. The geographic conditions of this region such as availability of human resources, water resources, vast open lands, wind power generation etc. also support to initiate mining of kimberlite pipes in this area. The availability of rough diamonds produced from local mines will make the polishing industry to meet its business needs during circumstances of the shortage of rough stone influx from foreign. Hence, although it demands liberal investments, reviving diamond mining in southern India can be materialised with a meticulous evaluation of these deposits ascertaining profitability. This will certainly help to restore the past glory of diamond mining in the southern part of the subcontinent.
DS2002-0652
2002
RamezaniHanson, R., Pancake, J., Crowley, J., Ramezani, Bowring, Dalziel, GoseCorrelation of 1.1 GA large igneous provinces on the Laurentia and Kalahari Cratons:Geological Society of America Annual Meeting Oct. 27-30, Abstract p. 561.South Africa, Botswana, Zimbabwe, OntarioTectonics, Gondwana
DS200412-0788
2004
Ramezani, J.Hanson, R.E., Gose, W.A., Crowley, J.L., Ramezani, J., Bowring, S.A., Bullen, D.S., Hall, R.P., Pancake, J.A.Paleoproterozoic intraplate magmatism and basin development on the Kaapvaal Craton: age, paleomagnetism and geochemistry of 1.93South African Journal of Geology, Vol. 107, 1/2, pp. 233-254.Africa, South AfricaCraton, tectonics, magmatism
DS200712-0097
2007
Ramezani, J.Bowring, S.A., Crowley, J.L., Ramezani, J., McLean, N., Condon, D., Schoene, B.High precision U Pb zircon geochronology: progress and potential.Plates, Plumes, and Paradigms, 1p. abstract p. A117.MantleGeochronology - EARTHTIME
DS2002-1304
2002
Ramiengar, A.S.Ramiengar, A.S.Carbonatite bodies of Dhanota Dhancholi area in Mahendragarh District, HaryanaJournal of the Geological Society of India, Vol. 60, 5, pp. 587-8.IndiaBrief - note, Carbonatite
DS1994-1432
1994
Ramires, A.P.Ramires, A.P., et al.Magnetic susceptibility of molecular carbon: nanotubes and fulleriteScience, Vol. 265, No. 5168, July 1, pp. 84-85.GlobalCarbon, Fullerine
DS201312-0200
2013
Ramirez, C.De Moor, M., Fischer, T.P., King, P.L., Botcharnikov, R.E., Hervig, R.L., Hilton, D.R., Barry, P.H., Mangasini, F., Ramirez, C.Volatile rich silicate melts from Oldoinyo Lengai volcano (Tanzania): implications for carbonatite genesis and eruptive behavior.Earth and Planetary Science Letters, Vol. 361, pp. 379-390.Africa, TanzaniaDeposit - Oldoinyo Lengai
DS202103-0405
2021
Ramirez, K.Schmitz, M., Ramirez, K., Mazuera, F., Avila, J., Yegres, L., Bezada, M., Levander, A.Moho depth map of northern Venezuela on wide-angle seismic studies.Journal of South American Earth Sciences, Vol. 107, 103088, 17p. PdfSouth America, VenezuelaGeophysics - seismics

Abstract: As part of the lithosphere, the crust represents Earth's rigid outer layer. Some of the tools to study the crust and its thickness are wide-angle seismic studies. To date, a series of seismic studies have been carried out in Venezuela to determine in detail the crustal thickness in the southern Caribbean, in the region of the Caribbean Mountain System in northern Venezuela, as well as along the Mérida Andes and surrounding regions. In this study, a review of the wide-angle seismic data is given, incorporating new data from the GIAME project for western Venezuela, resulting in a map of Moho depth north of the Orinoco River, which serves as the basis for future integrated models. Differences in Moho depths from seismic data and receiver function analysis are discussed. From the Caribbean plate, Moho depth increases from 20 to 25 km in the Venezuela Basin to about 35 km along the coast (except for the Falcón area where a thinning to less than 30 km is observed) and 40-45 km in Barinas - Apure and Guárico Basins, and Guayana Shield, respectively. Values of more than 50 km are observed in the Maturín Basin and in the southern part of the Mérida Andes.
DS1860-0447
1884
Ramirez, S.Ramirez, S.Noticia Historica de la Riqueza Mineral de Mexico Y de Su Actual Estado de Exploitacion.Mexico City: Officina Tipografica De la Secretaria De Foment, 768P.MexicoGemology
DS201908-1806
2019
Ramiz, M.M.Ramiz, M.M., Mondal, M,E.A., Farooq, S.H.Geochemistry of ultramafic-mafic rocks of the Madawara ultramafic complex in the southern part of the Bundelkhand craton, Central Indian Shield: implications for mantle sources and geodynamic setting.Geological Journal, Vol. 54, 4, pp. 2185-2207.Indiacraton

Abstract: Detailed field, petrography and whole-rock geochemical study was carried out in order to constrain the mantle sources and geodynamic setting of the Madawara Ultramafic Complex (MUC) of the Bundelkhand Craton. Studies reveal that there are two types of ultramafic rocks: (a) high-Mg ultrabasic/basic rocks and (b) undeformed ultramafic-mafic plutonic rocks. The high-Mg ultrabasic/basic rocks have undergone severe low-grade (greenschist) metamorphism and are characterized by stringer and veinlet structures of talc-tremolite-actinolite schists with alternate layers of serpentinites showing comparatively higher SiO2 (46.1-49.4 wt%), lower MgO (24.6-26.2 wt%), and higher Al2O3 (4.58-7.06 wt%) and CaO (2.72-6.77 wt%) compared to the undeformed ultramafic rocks. The undeformed ultramafic rocks (mainly harzburgite, lherzolite, and olivine websterite) are characterized by globular structures and have lower SiO2 (40-44.1 wt%), higher MgO (30.4-38 wt%) and lower Al2O3 (1.84-4.03 wt%) and CaO (0.16-3.14 wt%). The undeformed mafic rocks (mainly gabbro) occur as small pockets within the undeformed ultramafic rocks as well as independent outcrops. Limited variation in Nb/Th against Nb/Yb along with negative Nb-Ti anomalies of all the rock types in the multi-element diagram reveals the significant role of the metasomatized mantle in their genesis. All the rocks show enrichment in light rare earth element and large-ion lithophile elements compared to heavy rare earth elements and high-field strength elements. The geochemical characteristics coupled with Ce/Yb versus Ce variation of the rocks of MUC point towards two different sources for their genesis. The high-Mg ultrabasic/basic rocks are derived from partial melting of metasomatized mantle at shallow depth, while the undeformed ultramafic rocks were formed as a result of asthenospheric upwelling from a greater depth that induced the melting in the overlying lithosphere. Gabbro rocks represent the last and most evolved phase of the complex. Geochemical signatures suggest that the rocks of MUC were formed in a continental arc setting.
DS1985-0739
1985
Ramkin, A.H.Wooley, A.R., Ramkin, A.H., Elliott, C.J., Bishot, A.C., Niblett, D.Carbonatite dykes from the Richat dome, Mauritania and genesis of thedomeIndian Mineralogist, Sukheswala Volume, pp. 189-207MauritaniaCarbonatite
DS200712-0286
2007
Ramnko, E.F.Egorov, K.N., Ramnko, E.F., Podvysotsky, V.T., Sabulukov, S.M., Garanin, V.K., Dyakonov, D.B.New dat a on kimberlite magmatism in southwestern Angola.Russian Geology and Geophysics, Vol. 48, 4, pp. 323-336.Africa, AngolaMagmatism - kimberlites
DS1998-0906
1998
RamoLuttinen, A.V., Ramo, HuhmaNeodynmium and strontium isotopic and trace element composition of aMesozoic CFB suite from Dronning Maud Land: lithosphere and asthenosphere ...Karoo magmatismGeochimica et Cosmochimica Acta, Vol. 62, No. 15, pp. 2701-14.AntarcticaLithosphere, mantle
DS1994-1433
1994
Ramo, O.T.Ramo, O.T.1.3 Ga mafic magmatism of the St. Francois Mountains: implications for mantle composition mid-continentMineralogical Magazine, Vol. 58A, pp. 754-55. AbstractMissouriMafic magmatism, Geochronology
DS2001-0652
2001
Ramo, O.T.Landen, L.S., Ramo, O.T.Silicic magmatism and Early Paleoproterozoic continental rifting, east FIn land and adjacent RussiaGeological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p.81.abstract.Finland, RussiaMagmatism
DS200512-1110
2005
Ramo, O.T.Upton, B.G.J., Ramo, O.T., Heaman, L.M., Blichert-Toft, J., Kalsbeek, F., Barry, T.L., Jepsen, H.F.The Mesoproterozoic Zig-Zag Dal basalts and associated intrusions of eastern North Greenland: mantle plume lithosphere interaction.Contributions to Mineralogy and Petrology, Vol. 149, 1, pp. 40-56.Europe, GreenlandTectonics
DS200612-0791
2005
Ramo, O.T.Lehtinen, M., Nurmi, P., Ramo, O.T.Precambrian geology of Finland.Elsevier , 750p. $ 190.00Europe, FinlandBook - geology
DS201312-0928
2013
Ramo, O.T.Upton, B.G.J., Macdonald, R., Odling, N., Ramo, O.T., Baginski, B.Kungnaat, revisited. A review of five decades of research into an alkaline complex in South Greenland, with new trace element and Nd isotopic data.Mineralogical Magazine, Vol. 77, 4, pp. 523-550.Europe, GreenlandKungnaat
DS200612-0997
2004
Ramo, T.O'Brien, H., Ramo, T., Gehor, S.Carbonatite-kimberlite-alkaline rock field trip to southern and central Finland.Siilinjarvi, Kaavi-Kuopio, Kuhmo, IivaaraFinland Field Trip Guidebook June 2-4, 2004, 30p.Europe, FinlandGuidebook
DS200412-1222
2004
Ramokate, L.V.Mapeo, R.B.M., Armstrong, R.A., Kampunzu, A.B., Ramokate, L.V.SHRIMP U Pb zircon ages of granitoids from the western domain of the Kaapvaal Craton, southeastern Botswana: implications for crSouth African Journal of Geology, Vol. 107, 1/2, pp. 159-172.Africa, BotswanaGeochronology, tectonics
DS202104-0602
2021
Ramokgaba, L.Ramokgaba, L., Le Roex, A., Robey, J.Phlogopite-rich and phlogopite-poor kimberlite intrusions within the Du Toitspan kimberlite pipe, South Africa: petrogenetic relationships and localised source heterogeneity.Lithos, in press available, 35p. PdfAfrica, South Africadeposit - Du Toitspan

Abstract: Samples from three petrographically distinct, intrusive kimberlite bodies and associated kimberlite dykes from the eastern lobe of the Du Toitspan kimberlite pipe, Kimberley, South Africa, have been analysed for their bulk rock major and trace element compositions and their olivine and phlogopite compositions. The two dominant intrusive bodies (D13, D14) are distinguished by the one (D13) being phlogopite-rich and best classified as a macrocrystic hypabyssal phlogopite kimberlite, and the other (D14) being phlogopite-poor and best classified as a macrocrystic hypabyssal monticellite kimberlite. The minor D17 intrusive body is classified as a macrocrystic transitional hypabyssal serpentinized phlogopite kimberlite. The associated kimberlite dykes range texturally from aphanitic to macrocrystic and are classified as calcite kimberlites. The major kimberlite intrusions and their associated dykes show no evidence of crustal contamination and are characterised by broadly overlapping geochemistry except for distinctly higher K2O (> 2?wt%) and Al2O3 (>3?wt%) and flattening HREE patterns (Gd/YbN?=?6.5-7.0) in the D13 - phlogopite kimberlite compared to the D14 - monticellite kimberlite and the calcite kimberlite dykes (Gd/YbN?=?9.6-12.1). These distinguishing geochemical features of the D13 - phlogopite kimberlite are comparable to typical Group II kimberlites in southern Africa. However, their diagnostic incompatible trace element ratios (for example, Th/Nb, La/Nb, Ce/Pb, and Ba/Nb) are instead comparable to other kimberlite intrusions analysed in this study and to southern African Group I kimberlites in general. Semi-quantitative modelling suggests that these kimberlite intrusions could have derived by low (<1%) degrees of partial melting of a source region that is enriched in LREE (Lan?=?~6.1; Ybn?~?1.47) comparable to metasomatised peridotites from the underlying lithospheric mantle. The composition of the D13 phlogopite kimberlite is consistent with a partial melt of a modally metasomatised source containing a higher proportion of residual clinopyroxene relative to garnet (compared to that giving rise to the D14 monticellite kimberlite and calcite kimberlite dykes), as well as accessory amounts of phlogopite, i.e. a garnet phlogopite peridotite (GPP). The absence of K-anomalies on primitive mantle normalized diagrams for the D13 phlogopite kimberlite requires that phlogopite was not a residual phase during partial melting and was exhausted shortly before or at the moment of melt segregation. The higher Gd/Yb ratios and lower K2O in the D14 monticellite kimberlite and calcite kimberlite dykes can be explained by partial melting of a cryptically metasomatized, phlogopite - free, garnet peridotite (GP) source, containing a higher proportion of garnet relative to clinopyroxene. The low absolute K and strong negative K-anomaly on primitive mantle normalized diagrams for the D14 monticellite kimberlite were inherited from a source region that previously experienced cryptic metasomatism by a differentiated fluid already carrying a negative K-anomaly.
DS1860-0907
1895
Ramond, M.G.Ramond, M.G.Annuaire Geologique UniverselleParis, Vol. X, 1893, PP. 595-654.IndiaHistory
DS1989-1251
1989
Ramon-Lluch, R.Ramon-Lluch, R., Martinez-Torres, L.M., Eguiluz, L.RAFOLD: a BASIC program for the geometric classification of foldsComputers and Geosciences, Vol. 15, No. 6, pp. 989-996GlobalComputer, Program -RAFOLD.
DS1991-1610
1991
Ramos, .N.Smith, C.B., Ramos, .N., Hatton, C.J., Horsch, H., DamarupurshadEclogite xenolith with exsolved sanidine from the Proterozoic Kuruman kimberlite province, northern Cape, R.S.A.Proceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 383-384South AfricaZero, geochronology, xenoliths, Eclogite xenoliths
DS200712-0868
2006
Ramos, F.C.Ramos, F.C., Reid, M.R., Sims, K.W.W.Re-evaluating the mantle structure underlying the southwestern US.Geochimica et Cosmochimica Acta, In press availableUnited States, Colorado PlateauGeochronology
DS201212-0581
2012
Ramos, F.C.Reid, M.R., Boucher, R.A., Ichert-Toft, J., Levander, A., Liu, K., Miller, M.S., Ramos, F.C.Melting under the Colorado Plateau, USA.Geology, Vol. 40, 5, pp. 387-390.United States, Colorado PlateauMelting
DS200812-0334
2008
Ramos, J.M.F.Ezzouhari, H., Ribeiro, M.L., AitAyad, N., Moreira, M.E., Charif, A., Ramos, J.M.F., De Oliveira, D.P.S., Coke, C.The magmatic evolution at the Moroccan outboard of the West African Craton between the Late Neoproterozoic and the Early Palaeozoic.Special Publication - Geological Society of London, No. 297, pp. 329-344.Africa, MoroccoMagmatism
DS1950-0455
1959
Ramos, J.R.Barbosa, O., Ramos, J.R.Territorio de Rio Blanco; Aspectos Principais de Geomorfologia, Da Geologia E das Possibilidades Minerais de Sua Zona SetentrionalBol. Div. Geol. Mineral, No. 196, 49P.South America, BrazilBlank
DS200512-1137
2004
Ramos, M.L.S.Ventura Santos, R., Souza de Alvarenga, C.J., Babinski, M., Ramos, M.L.S., Cukrov, N., Fonsec, M.A., Da NorbregaCarbon isotopes of Mesoproterozoic Neoproterozoic sequences from southern Sao Francisco craton and Aracuai Belt, Brazil: paleogeorgraphic implications.Journal of South American Earth Sciences, Vol. 18, 1, Dec. 30, pp. 27-39.South America, BrazilGeomorphology, glaciation, geochronology,carbonatites
DS1996-1173
1996
Ramos, R.C.Reid, M.R., Ramos, R.C.Chemical dynamics of enriched mantle in the southwestern United States:thorium isotope evidence.Earth and Planetary Science Letters, Vol. 138, No. 1/4, Feb. 1, pp. 67-82.Nevada, Arizona, ColoradoGeochemistry, geochronology, Mantle geodynamics
DS1988-0562
1988
Ramos, V.A.Ramos, V.A.Late Proterozoic Early Paleozoic of South America - a collisional history.Episodes, Vol. 11, No. 3, Sept. pp. 168-173.Paraguay, BrazilGondwana, Tectonics
DS1989-0755
1989
Ramos, V.A.Kay, S.M., Ramos, V.A., Mpodozis, C., Sruoga, P.Late Paleozoic to Jurassic silicic magmatism at theGondwanamargin:analogy to the middle Proterozoic in North America?Geology, Vol. 17, No. 4, April pp. 324-328MidcontinentTectonics
DS1989-1252
1989
Ramos, V.A.Ramos, V.A.The birth of southern South AmericaAmerican Scientist, Vol. 77, No. 5, Sept-October pp. 444-450South AmericaTectonics, Overview
DS1993-0956
1993
Ramos, V.A.Mahlburg Kay, S., Ramos, V.A., Marquez, M.Evidence in Cerro Pampa volcanic rocks for slab melting prior to Ridge-Trench collision in southern South AmericaJournal of Geology, Vol. 101, No. 6, November pp. 703-714Argentina, PatagoniaAdakite flows, Magmatic, melt
DS1996-1155
1996
Ramos, V.A.Ramos, V.A., Cegarra, M., Cristallini, E.Cenozoic tectonics of the High Andes of west central Argentin a (30- 36 d Slatitude)Tectonophysics, Vol. 259, No. 1-3, June 30, pp. 185-200ArgentinaTectonics
DS2002-0565
2002
Ramos, V.A.Giambiagi, L.B., Ramos, V.A.Structural evolution of the Andes in a transitional zone beneath flat and normal subduction 33-33 ....Journal of South American Earth Sciences, Vol.15,1,Apr.pp.101-116.Argentina, Chile, AndesTectonics
DS2002-1305
2002
Ramos, V.A.Ramos, V.A., Cristallini, E.O., Perez, D.J.The Pampean flat slab of the central AndesJournal of South American Earth Sciences, Vol.15,1,Apr.pp.59-78.Chile, AndesSubduction, Slab
DS201012-0609
2010
Ramos, V.A.Ramos, V.A., Vukovich, G., Martino, R., Otamendi, J.Pampia: a large cratonic block missing in the Rodinia supercontinentJournal of Geodynamics, Vol. 50, 3-4, pp. 243-255.South AmericaCraton, crustal evolution
DS1991-1396
1991
Ramos, Z.Ramos, Z., Skinner, E.M.W., Bristow, J.W., Robinson, D.N.Kimberlites and the mantle in South AfricaXiii International Gemmological Conference Held South Africa, Stellenbosch, 2p.abstractSouth AfricaMantle, Diamond genesis
DS1998-1648
1998
Ramos, Z.Zinngrebe, E., Jacob, D., Ramos, Z., Smith, C.B.A model for eclogite peridotite interactions: activity driven with evidence from Zero eclogiteMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1705-6.South AfricaSubduction, eclogite, Deposit - Zero
DS1994-1434
1994
Ramos, Z.N.Ramos, Z.N., Smith, C.B., Horsch, H.E.Eclogite xenoliths from the Zero kimberlite, Kuruman area, RSAInternational Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 8-10.South AfricaEclogite xenoliths, Deposit -Zero
DS202007-1131
2020
Ramotoroko, C.Chisenga, C., Van der Meijde, M., Yan, J., Fadel. I., Atekwana, E.A., Steffen, R., Ramotoroko, C.Gravity derived crustal thickness model of Botswana: its implication for the Mw 6.5 April 3, 2017, Botswana earthquake. Tectonophysics, Vol. 787, 228479 12p. PdfAfrica, Botswanageophysics - gravity

Abstract: Botswana experienced a Mw 6.5 earthquake on 3rd April 2017, the second largest earthquake event in Botswana's recorded history. This earthquake occurred within the Limpopo-Shashe Belt, ~350 km southeast of the seismically active Okavango Rift Zone. The region has no historical record of large magnitude earthquakes or active faults. The occurrence of this earthquake was unexpected and underscores our limited understanding of the crustal configuration of Botswana and highlight that neotectonic activity is not only confined to the Okavango Rift Zone. To address this knowledge gap, we applied a regularized inversion algorithm to the Bouguer gravity data to construct a high-resolution crustal thickness map of Botswana. The produced crustal thickness map shows a thinner crust (35-40 km) underlying the Okavango Rift Zone and sedimentary basins, whereas thicker crust (41-46 km) underlies the cratonic regions and orogenic belts. Our results also show localized zone of relatively thinner crust (~40 km), one of which is located along the edge of the Kaapvaal Craton within the MW 6.5 Botswana earthquake region. Based on our result, we propose a mechanism of the Botswana Earthquake that integrates crustal thickness information with elevated heat flow as the result of the thermal fluid from East African Rift System, and extensional forces predicted by the local stress regime. The epicentral region is therefore suggested to be a possible area of tectonic reactivation, which is caused by multiple factors that could lead to future intraplate earthquakes in this region.
DS1994-1435
1994
Ramoz, Z.Ramoz, Z.Eclogite xenoliths from the Kuruman kimberlites, South AfricaUniversity of Witwatersrand, MSc. thesisSouth AfricaXenoliths, Thesis
DS201112-0867
2011
RampilovRipp, G.S., Doboshkevich, A.G., Ripp, G.S., Lastochkin, Izbrodin, RampilovA way of carbonatite formation from alkaline gabbros, Oshurkovo massif.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.39-41.RussiaOshurkovo
DS201112-0868
2011
RampilovRipp, G.S., Doboshkevich, A.G., Ripp, G.S., Lastochkin, Izbrodin, RampilovA way of carbonatite formation from alkaline gabbros, Oshurkovo massif.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.39-41.RussiaOshurkovo
DS1994-1436
1994
Rampino, .R.Rampino, .R.Tillites, diamictites and ballistic ejecta of large impactsJournal of Geology, Vol. 102, No. 4, July pp. 439-456GlobalSedimentology, Glaciology
DS1984-0603
1984
Rampino, M.R.Rampino, M.R., Stothers, R.B.Geological Rhythms and Cometary ImpactsNasa/national Technical Information Service, No. N84-32327, 22P.GlobalCraters, Tectonics
DS1991-0204
1991
Rampino, M.R.Caldeira, K., Rampino, M.R.The Mid-Cretaceous super flume, carbon dioxide, and global warmingGeophysical Research Letters, Vol. 18, No. 6, June pp. 987-990GlobalCarbon cycle, Climates
DS1991-0205
1991
Rampino, M.R.Caldeira, K., Rampino, M.R.The Mid Cretaceous super plume: carbon dioxide, and global warmingGeol. Res. Let., Vol. 18, No. 6, June pp. 987-90.MantlePlumes
DS1993-1280
1993
Rampino, M.R.Rampino, M.R., Caldeira, K.Major episodes of geologic change: correlations, time structure and possible causesEarth and Planetary Science Letters, Vol. 114, No. 2-3, January pp. 215-228GlobalTectonics, Mantle, continent, Rifting
DS201312-0731
2013
Rampino, M.R.Rampino, M.R., Prokoph, A.Are mantle plumes periodic?EOS Transaction of AGU, Vol. 94, 12, March 19, pp. 113-120.MantlePlume cycles
DS1991-1397
1991
Rampone, E.Rampone, E., Bottazzi, P., Ottolini, L.Complementary Titanium and Zirconium anomalies in orthopyroxene and clinopyroxene from mantle peridotitesNature, Vol. 354, No. 6354, Dec. 19, 26 pp. 518-520MantleClinopyroxenes, titanium, zirconium, Peridotites
DS1999-0626
1999
Rampone, E.Scambelluri, M., Rampone, E.magnesium metasomatism of oceanic gabbros and its control on Ti clinohumite formation during eclogization.Contributions to Mineralogy and Petrology, Vol. 135, No. 1, pp. 1-17.GlobalMetasomatism, Eclogites
DS2001-0919
2001
Rampone, E.Piccardo, G.B., Rampone, E.Strongly depleted Mid Ocean Ridge Basalt (MORB) melts at extensional settings: peculiar mafic ultramafic intrusive suiteMt. MaggioreGeological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p. 118.abstract.France, CorsicaPeridotite
DS200412-1617
2004
Rampone, E.Rampone, E., Romairone, A., Hofmann, A.W.Contrasting bulk and mineral chemistry in depleted mantle peridotites: evidence for reactive porous flow.Earth and Planetary Science Letters, Vol. 218, 3-4, Feb. 15, pp. 491-506.Europe, AlpsMineral chemistry - not specific to diamonds
DS1920-0245
1925
Ramsay, A.Ramsay, A.In Search of the Precious StoneNew York: A. Ramsay And Co., 50P.GlobalDiamonds Notable, Kimberley
DS1994-1713
1994
Ramsay, D.A.Sturt, B.A., Melezhik, V.A., Ramsay, D.A.Early Proterozoic regolith at Pasvik, northeast Norway: paleoenvironmental implications for the Baltic ShieldTerra Nova, Vol. 6, No. 6, pp. 618-632NorwayPaleoclimatology, Sedimentology -regolith
DS1986-0506
1986
Ramsay, R.Lucas, H., Ramsay, R., Hall, A.E., Smith, C.B., Sobolev, N.V.Garnets from West Australian kimberlites and associated rocksProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 270-272AustraliaBlank
DS1995-1541
1995
Ramsay, R.Ramsay, R.Significance of indicator minerals in the exploration and evaluation Of kimberlitic rocks.University of West. Australian Key Centre, held Feb. 15, 16th., 5p.AustraliaDiamond exploration, Indicator minerals, geochemistry
DS1995-1542
1995
Ramsay, R.Ramsay, R.The discovery of the Lower Bulgurri kimberlite - a new diamondiferous fissure in the North Kimberley.Prospectors and Developers Association of Canada (PDAC) Preprint, 6p.Australia, Western AustraliaGeology, Deposit -Lower Bulgurri
DS1998-1421
1998
Ramsay, R.Sumner, J., Wilkes, J., Robins, J., Ramsay, R.A geophysical case study of the Ashmore kimberlite cluster, North KimberleyProvince, Western Australia.Australian Society of Exploration Geophysicists (ASEG) International, p. 109. abstractAustraliaGeophysics, Deposit - Ashmore
DS1998-1471
1998
Ramsay, R.Tompkins, L., Taylor, W., Ramsay, R., Armstrong, R.The mineralogy and geochemistry of the Kamafugitic Tres Barras intrusion, Mat a da Corda, Minas Gerais, Brasil.7th International Kimberlite Conference Abstract, pp. 920-2.Brazil, Minas GeraisLeucitites, kamafugites, Deposit - Tres Barras
DS201012-0258
2010
Ramsay, R.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
DS201112-0230
2011
Ramsay, R.Czuppon, G., Gwalani, L.G., Demeny, A., Ramsay, R., Rogers, K., Eves, A., Szabo, Cs.C, O, H isotope compositions of the Wilmott and Yungul carbonatites and the associated fluorites in the Speewah dome, Kimberley region, Australia.Goldschmidt Conference 2011, abstract p.711.AustraliaCarbonatite
DS1989-0901
1989
Ramsay, R.R.Lucas, H., Ramsay, R.R., Hall, A.E., Smith, C.B., Sobolev, N.V.Garnets from Western Australian kimberlites and related rocksGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 809-819AustraliaLamproite, Heavy minerals, Geochemist
DS1990-1211
1990
Ramsay, R.R.Ramsay, R.R., Rock, N.M.S.Comparative garnet, pyroxene, chromite and magnesium-ilmenite xenocryst compositions in selected kimberlitic sources and their relevance to diamondexplorationGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 243-244. AbstractAustraliaMantle nodules, Garnet analyses -Xenocrys
DS1991-1740
1991
Ramsay, R.R.Tompkins, L.A., Ramsay, R.R.The Boa Esperanca and Cana Verde pipes, Corrego d'Anta, Minas Gerais, BrasilProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 429-431Brazil, Inga, Quartel, Portugal, Minas Gerais, Boa EsperancaBambui province, lineament, structure, craton, Mineral chemistry
DS1993-1281
1993
Ramsay, R.R.Ramsay, R.R.Geochemistry of diamond indicator mineralsUniversity of Western Australia, Ph.d. thesisAustraliaGeochemistry -diamonds, Thesis
DS1994-1437
1994
Ramsay, R.R.Ramsay, R.R., Edwards, D., Taylor, W.R., Rock, N.M.S., Griffin, B.J.Compositions of garnet, spinel Aries Diamondiferous kimberlite pipe, Kimberley Block, implications for explJournal of Geochem. Exploration, Vol. 51, No. 1, Apr. pp. 59-78.AustraliaGeochemistry, Deposit -Aries
DS1994-1438
1994
Ramsay, R.R.Ramsay, R.R., Tompkins, L.A.The geology, heavy mineral concentrate mineralogy, diamond prospectivity Of the Boa Esperanca and Cana Verde pipes.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 329-345.Brazil, Minas Gerais, Mato GrossoGeochemistry, Deposit -Boa Esperanca, Cana Verde
DS1994-1628
1994
Ramsay, R.R.Smith, C.B., Lucas, H., Hall, A.E., Ramsay, R.R.Diamond prospectivity and indicator mineral chemistry: a western Australianperspective.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 312-318.AustraliaGeochemistry, Diamond exploration
DS1994-1793
1994
Ramsay, R.R.Towie, N.J., Bush, M.D., Manning, E.R., Marx, M.R., Ramsay, R.R.The Aries Diamondiferous kimberlite pipe central Kimberley Block, westernAustralia: exploration, setting and evaluation.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 319-328.AustraliaDiamond exploration, Deposit -Aries
DS1996-1156
1996
Ramsay, R.R.Ramsay, R.R.Kimberlite discoveries in the northern Kimberleys, Western AustraliaAustralia Nat. University of Diamond Workshop July 29, 30., 2p.AustraliaKimberley Block, Halls Creek, Exploration -brief overview
DS1920-0082
1921
Ramsay, W.Ramsay, W.En Melilitforande Djupbergart Fran Turja Pa Sydsidan Av Kolahalvon.Geol. Foren. Forhandl., Vol. 43, P. 488.Norway, ScandinaviaUltramafic And Related Rocks
DS1960-0610
1965
Ramsay, W.Sturt, B.A., Ramsay, W.The Alkaline Complex of the Breivikbotn Area, Soroy, NorwayNorges Geol. Unders. Skr., No. 231Norway, ScandinaviaUltramafic And Related Rocks
DS2003-0575
2003
Ramsay, W.R.H.Hell, A.J., Ramsay, W.R.H., Rheinberger, G., Pooley, S.The geology, age, mineralogy and near surface features of the Merlin kimberlites8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractAustraliaKimberlite geology and economics, Deposit - Merlin
DS200412-1618
2003
Ramsay, W.R.H.Ramsay, W.R.H., Hell, A., Reinberger, G., Pooley, S.The geology, age, near surface features and mineralogy of the Merlin kimberlite field, Northern Territory, Australia.Geological Society of Australia Abstracts, Vol. 70, p. 54. 1p.Australia, Northern TerritoryDeposit overview - Merlin
DS1990-1212
1990
Ramsden, A.R.Ramsden, A.R., French, D.H.Routine trace -element capabilities of electron microprobe analysis in mineralogical investigations: an empirical evaluation of performance usingspectroM.Canadian Mineralogist, Vol. 28, Pt. 1, March pp. 171-180GlobalMircoprobe analysis, Spectrometry
DS1993-1282
1993
Ramsden, A.R.Ramsden, A.R., French, D.H., Chalmers, D.I.Volcanic hosted rare-metals deposit at Brockman, Western AustraliaMineralium Deposita, Vol. 28, pp. 1-12AustraliaRare earths, Deposit -Brockman
DS201712-2681
2018
Ramsden, F.Creus, P.K., Basson, I.J., Stoch, B., Mogorosi, O., Gabanakgosi, K., Ramsden, F., Gaegopolwe, P.Structural analysis and implicit 3D modelling of Jwaneng mine: insights into deformation of the Transvaal Supergroup in SE Botswana.Journal of African Earth Sciences, Vol. 137, pp. 9-21.Africa, Botswanadeposit - Jwaneng

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

Abstract: Country rock at Jwaneng Diamond Mine provides a rare insight into the deformational history of the Transvaal Supergroup in southern Botswana. The ca. 235 Ma kimberlite diatremes intruded into late Archaean to Early Proterozoic, mixed, siliciclastic-carbonate sediments, that were subjected to at least three deformational events. The first deformational event (D1), caused by NW-SE directed compression, is responsible for NE-trending, open folds (F1) with associated diverging, fanning, axial planar cleavage. The second deformational event (D2) is probably progressive, involving a clockwise rotation of the principal stress to NE-SW trends. Early D2, which was N-S directed, involved left-lateral, oblique shearing along cleavage planes that developed around F1 folds, along with the development of antithetic structures. Progressive clockwise rotation of far-field forces saw the development of NW-trending folds (F2) and its associated, weak, axial planar cleavage. D3 is an extensional event in which normal faulting, along pre-existing cleavage planes, created a series of rhomboid-shaped, fault-bounded blocks. Normal faults, which bound these blocks, are the dominant structures at Jwaneng Mine. Combined with block rotation and NW-dipping bedding, a horst-like structure on the northwestern limb of a broad, gentle, NE-trending anticline is indicated. The early compressional and subsequent extensional events are consistent throughout the Jwaneng-Ramotswa-Lobatse-Thabazimbi area, suggesting that a large area records the same fault geometry and, consequently, deformational history. It is proposed that Jwaneng Mine is at or near the northernmost limit of the initial, northwards-directed compressional event.
DS1990-1213
1990
Ramsey, F.P.Ramsey, F.P.Weight or the value of knowledgeBritish Journal of for the Philosphy of Science, Vol. 41, No. 1, March pp. 1-4GlobalInformation, Value
DS201012-0610
2010
Ramsey, M.H.Ramsey, M.H., Boon, K.A.New approach to geochemical measurement: estimation of measurement uncertainty from sampling, rather than an assumption of representative.Geostandards and Geoanaltyical Research, Vol. 34, 3, pp. 293-304.TechnologySampling - not specific to diamonds
DS200512-0533
2004
Ramsey, M.S.King, P.L., Ramsey, M.S., Swayze, G.A.Infrared spectroscopy in geochemistry, exploration geochemistry and remote sensing.Mineralogical Association of Canada, SC33, 284p. $ 40.Book - infrared spectroscopy not specific to diamonds
DS201412-0752
2014
Ramsey, M.S.Rooney, T.O., Bastow, I.D., Keir, D., Mazzarini, F., Movsesian, E., Grosfils, E.B., Zimbelman, J.R., Ramsey, M.S., Ayalew, D., Yirgu, G.The protracted development of focused magmatic intrusion during continental rifting.Tectonics, Vol. 33, 6, pp. 875-897.Africa, EthiopiaPrecambrian lineaments
DS1991-1609
1991
Ramsey, R.R.Smith, C.B., Lucas, H., Hall, A.E., Ramsey, R.R.Diamond prospectivity from indicator mineralogy: a western AustralianperspectiveProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 380-382AustraliaHeavy mineral sampling, Hadfields, Pteropus, Argyle, Ellendale, peridotite, harzburgite, lherzolite, Skerring
DS1989-0794
1989
Ramshorn, Ch.Klein, H., Pflug, R., Ramshorn, Ch.Shaded perspective views by computer: a new tool for geologistsGeobyte, August pp. 16, 18-24. Database # 18148GlobalComputer, Program - perspective views
DS200512-0243
2004
Ramstein, G.Donnadieu, Y., Ramstein, G., Godderis, Y., Fluteau, F.Global tectonic setting and climate of the Late Neoproterozoic: a climate geochemical coupled study.American Geophysical Union, Geophysical Monograph, No. 146, pp. 79-90.Geomorphology - tectonics
DS200812-0638
2008
Ramstein, G.Le Hir, G., Ramstein, G., Donnadieu, Y., Godderis, Y.Scenario for the evolution of atmospheric pCO2 during a snowball Earth.Geology, Vol. 36, 1, pp. 47-50.MantleCarbon cycle
DS202001-0034
2019
Ramstein, G.Ramstein, G., Godderis, Y., Donnadieu, Y., Sepulchre, P., Fluteau, F., Zhang, Z., Zhang, R., Su, B., Jiang, D., Schuster, M., Besse, J.Some illustrations of large tectonically driven climate changes in Earth history.Tectonics, doi.org/10.1029/ 2019TC005569Mantletectonics

Abstract: For the celebration of the 50th anniversary of the publication of the pioneering papers that established the basis of plate tectonic, this paper was solicited to illustrate the close relation between tectonics and climate. Amongst the large spectrum of interactions that depict how tectonics modified the climate at geological time steps, we choose to illustrate two major issues: (1) How the “tryptic” climate/long-term carbon cycle/tectonics explains the extraordinary glacial episode (717-635 Ma) occurring during Neoproterozoic era? (2) How major tectonic events (i.e., the slow shrinkage of a huge epicontinental sea and the uplift of large mountains ranges in Asia and Africa) drastically changed the climate and shaped the pattern of present-day monsoons systems. This paper is the result of long-standing collaboration with many researchers from different countries.
DS202009-1620
2020
Rana, S.Choudhary, S., Sen, K., Kumar, S., Rana, S., Ghosh, S.Forsterite repricipitation and carbon dioxide entrapment in the lithospheric mantle during its interaction with carbonatitic melt: a case study from the Sung Valley ultramafic-alkaline-carbonatite complex, Meghalaya, NE India.Geological Magazine, 10.1017/S001675 68200000631 12p.Indiacarbonatites

Abstract: Carbonatite melts derived from the mantle are enriched in CO2- and H2O-bearing fluids. This melt can metasomatize the peridotitic lithosphere and liberate a considerable amount of CO2. Experimental studies have also shown that a CO2-H2O-rich fluid can form Fe- and Mg-rich carbonate by reacting with olivine. The Sung Valley carbonatite of NE India is related to the Kerguelen plume and is characterized by rare occurrences of olivine. Our study shows that this olivine is resorbed forsterite of xenocrystic nature. This olivine bears inclusions of Fe-rich magnesite. Accessory apatite in the host carbonatite contains CO2-H2O fluid inclusions. Carbon and oxygen isotopic analyses indicate that the carbonatites are primary igneous carbonatites and are devoid of any alteration or fractionation. We envisage that the forsterite is a part of the lithospheric mantle that was reprecipitated in a carbonatite reservoir through dissolution-precipitation. Carbonation of this forsterite, during interaction between the lithospheric mantle and carbonatite melt, formed Fe-rich magnesite. CO2-H2O-rich fluid derived from the carbonatite magma and detected within accessory apatite caused this carbonation. Our study suggests that a significant amount of CO2 degassed from the mantle by carbonatitic magma can become entrapped in the lithosphere by forming Fe- and Mg-rich carbonates.
DS202101-0003
2020
Rana, S.Choudhary, S., Sen, K., Kumar, S., Rana, S., Ghosh, S.Forsterite reprecipitation and carbon dioxide entrapment in the lithospheric mantle during its interaction with carbonatitic melt: a case study from the Sung Valley ultramafic-alkaline-carbonatite complex, Meghalaya, NE India.Geological Magazine, doi:1017/S001 6756820000631, 12p.Indiadeposit - Sung Valley

Abstract: Carbonatite melts derived from the mantle are enriched in CO2- and H2O-bearing fluids. This melt can metasomatize the peridotitic lithosphere and liberate a considerable amount of CO2. Experimental studies have also shown that a CO2-H2O-rich fluid can form Fe- and Mg-rich carbonate by reacting with olivine. The Sung Valley carbonatite of NE India is related to the Kerguelen plume and is characterized by rare occurrences of olivine. Our study shows that this olivine is resorbed forsterite of xenocrystic nature. This olivine bears inclusions of Fe-rich magnesite. Accessory apatite in the host carbonatite contains CO2-H2O fluid inclusions. Carbon and oxygen isotopic analyses indicate that the carbonatites are primary igneous carbonatites and are devoid of any alteration or fractionation. We envisage that the forsterite is a part of the lithospheric mantle that was reprecipitated in a carbonatite reservoir through dissolution-precipitation. Carbonation of this forsterite, during interaction between the lithospheric mantle and carbonatite melt, formed Fe-rich magnesite. CO2-H2O-rich fluid derived from the carbonatite magma and detected within accessory apatite caused this carbonation. Our study suggests that a significant amount of CO2 degassed from the mantle by carbonatitic magma can become entrapped in the lithosphere by forming Fe- and Mg-rich carbonates.
DS202103-0372
2021
Rana, S.Choudhary, S., Sen, K., Kumar, S., Rana, S., Ghosh, S.Forsterite reprecipitation and carbon dioxide entrapment in the lithospheric mantle during its interaction with carbonatitic melt: a case study from the Sung Valley ultramafic-alkaline-carbonatite complex, Meghalaya, NE India.Geological Magazine, Vol. 158, 3, pp. 475-486.Indiadeposit - Sung Valley

Abstract: Carbonatite melts derived from the mantle are enriched in CO2- and H2O-bearing fluids. This melt can metasomatize the peridotitic lithosphere and liberate a considerable amount of CO2. Experimental studies have also shown that a CO2-H2O-rich fluid can form Fe- and Mg-rich carbonate by reacting with olivine. The Sung Valley carbonatite of NE India is related to the Kerguelen plume and is characterized by rare occurrences of olivine. Our study shows that this olivine is resorbed forsterite of xenocrystic nature. This olivine bears inclusions of Fe-rich magnesite. Accessory apatite in the host carbonatite contains CO2-H2O fluid inclusions. Carbon and oxygen isotopic analyses indicate that the carbonatites are primary igneous carbonatites and are devoid of any alteration or fractionation. We envisage that the forsterite is a part of the lithospheric mantle that was reprecipitated in a carbonatite reservoir through dissolution-precipitation. Carbonation of this forsterite, during interaction between the lithospheric mantle and carbonatite melt, formed Fe-rich magnesite. CO2-H2O-rich fluid derived from the carbonatite magma and detected within accessory apatite caused this carbonation. Our study suggests that a significant amount of CO2 degassed from the mantle by carbonatitic magma can become entrapped in the lithosphere by forming Fe- and Mg-rich carbonates.
DS200512-0006
2005
Ranali, G.Afonso, J.C., Ranali, G., Fernandez, M.Thermal expansivity and elastic properties of the lithospheric mantle: results from mineral physics of composites.Physics of the Earth and Planetary Interiors, Vol. 149, 3-4, April 15, pp. 279-306.MantleGeothermometry
DS1997-0345
1997
Ranalli, G.Fernandez, M., Ranalli, G.The role of rheology in extensional basin formation modellingTectonophysics, Vol. 282, No. 1-4, Dec. 15, pp. 129=146GlobalBasin, Tectonics - extensional
DS1997-0945
1997
Ranalli, G.Ranalli, G.Rheology of the lithosphere in time and spaceGeological Society of London, Orogeny through Time, No. 121, pp. 19-37.Alberta, Western CanadaTectonics - deformation, Lithosphere
DS2001-0964
2001
Ranalli, G.Ranalli, G.Experimental tectonics: from Sir James Hall to the presentJournal of Geodynamics, Vol. 32, No. 1-2, pp. 65=76.GlobalTectonics - experimental, History
DS2001-0965
2001
Ranalli, G.Ranalli, G.Mantle rheology: radial and lateral viscosity variations inferred from microphysical creep laws.Journal of Geodynamics, Vol. 32, No. 4-5, pp. 425-44.MantleTectonics, rheology, Geophysics - power law creep
DS2001-0966
2001
Ranalli, G.Ranalli, G.Mantle rheology: radial and lateral viscosity variations inferred from microphysical creep laws.Journal of Geodynamics, Vol. 32, No. 4-5, pp. 425-44.MantleBlank
DS2003-1127
2003
Ranalli, G.Ranalli, G.How soft is the crust?Tectonophysics, Vol. 361, 3-4, pp. 319-20.MantlePetrology
DS200512-0010
2004
Ranalli, G.Alfonso, J.C., Ranalli, G.Crustal and mantle strengths in continental lithosphere: is the jelly sandwich model obsolete?Tectonophysics, Vol. 394, 3-4, Dec. 1-, pp. 221-232.MantleRheology, composition
DS200712-0869
2007
Ranalli, G.Ranalli, G., Piccardo, G.B., Corona Chavez, P.Softening of the continental lithsopheric mantle by asthenospheric melts and the continental extension /oceanic spreading transition.Journal of Geodynamics, Vol. 43, 4-5, pp. 450-464.MantleMelting
DS200812-0017
2008
Ranalli, G.Alfonso, J.C., Fernandez, M., Ranalli, G., Griffin, W.L., Connolly, J.A.D.Integrated geophysical petrological modelling of the lithosphere and sublithospheric upper mantle: methodology and applications.Journal of Geophysical Research, in press available ( 97p.)MantleModels
DS201012-0003
2010
Ranalli, G.Afonso, J.C., Ranalli, G., Fernandez, M., Griffin, W.L., O'Reilly, S.Y., Faul, U.On the VpVs-Mg# correlation in mantle peridotites: implications for the identification of thermal and compositional anomalies in the upper mantle.Earth and Planetary Science Letters, Vol. 289, 3-4, pp. 606-618.MantleChemistry
DS201012-0197
2010
Ranalli, G.Fernadez, M., Afonso, J.C., Ranalli, G.The deep lithospheric structure of the Namibian volcanic margin.Tectonophysics, Vol.481, 1-4, pp. 68-81.Africa, NamibiaTectonics
DS1989-0933
1989
Rancan, J.P.Marcelot, G., Dupuy, C., Dostal, J., Rancan, J.P., Pouclet, A.Geochemistry of mafic volcanic rocks from the Lake Kivu (Zaire and Rwanda)section of the western branch Of the African riftJournal of Volcanology and Geothermal Research, Vol. 39, No. 1, October pp. 73-88Democratic Republic of CongoTectonics, Rifting
DS2003-1128
2003
Rancic, D.Rancic, D., Djordjevikajan, S.MapEdit: solution to continuous raster map creationComputers and Geosciences, Vol. 29, 2, pp. 115-122.GlobalComputer - program
DS200412-1619
2003
Rancic, D.Rancic, D., Djordjevikajan, S.MapEdit: solution to continuous raster map creation.Computers & Geosciences, Vol. 29, 2, pp. 115-122.TechnologyComputer - program
DS1994-0973
1994
Rancourt, D.G.Lalonde, A.E., Rancourt, D.G., Chao, G.Y.iron bearing trioctahedral micas from Mont Saint Hilaire, QuebecGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p.QuebecMineralogy, Mont Saint Hilaire
DS1996-0802
1996
Rancourt, D.G.Lalonde, A.E., Rancourt, D.G., Chao, G.Y.iron bearing trioctahedral micas from Mont Saint Hilaire Quebec, CanadaMineralogical Magazine, Vol. 60, pp. 447-460.QuebecAlkaline rocks, Deposit -Mont St. Hilaire region
DS1985-0554
1985
Rand, S.C.Rand, S.C., Deshazer, L.G.Visible Color Centre Laser in DiamondOptics Letters, Vol. 10, No. 10, October pp. 481-483GlobalSpectroscopy, Diamond Morphology
DS1960-0086
1960
Randall, B.A.O.Randall, B.A.O.Sagvandites of Lyngen, Troms, North NorwayInternational Geological Congress 21ST., REPORT No. 13, PP. 443-451.Norway, ScandinaviaPetrology
DS1997-0944
1997
Randive, K.R.Ramasamy, R., Gwalani, L.G., Randive, K.R., Mulai, B.P.Geology of the Indian carbonatites and evolution of alkali carbonatite magma in peninsular India.Geological Association of Canada (GAC) Abstracts, POSTER.IndiaCarbonatite
DS200812-0933
2008
Randive, K.R.Randive, K.R.Compositional variation of micas from the lamprophyre dykes of Bakhatgarh Phulmal area, Jhabua District, M P. India.Indian Dykes: editors Srivastava, Sivaji, Chalapathi Rao, pp. 133-141.India, Madhya PradeshLamprophyre, mineralogy
DS201112-0842
2011
Randive, K.R.Randive, K.R.Occurrence of xenoliths in the lamprophyre and picrobasalt dykes of Bakhatgarh Phulmal area, Jhabula district, Madhya Pradesh, India.In: Dyke swarms: keys to geodynamic interpretation, Part 1, pp. 301-313.IndiaLamprophyre
DS201801-0052
2017
Randive, K.R.Randive, K.R.Primary carbonate-silicate association in the pelletal lapilli: first direct evidence of carbonated peridotitic mantle source for Amba Dongar carbonatites, Deccan igneous province, India.Carbonatite-alkaline rocks and associated mineral deposits , Dec. 8-11, abstract p. 30.Indiadeposit - Amba Dongar

Abstract: Pelletal lapilli are discrete sub-spherical clasts with a central fragment mantled by a rim of probable juvenile origin. They typically range in size from <1 mm – 60 mm, and occur as accessory components of pipe-filling volcaniclastic rocks such as kimberlites, carbonatites, kamafugites, melilitites and orangeites. They have been variously referred to as ‘tuffacitic lapilli’, ‘spherical or elliptical lapilli’, ‘Pele’s tears’, ‘spinning droplets’, ‘cored lapilli’, or ‘concentric shelled lapilli. Their presence has been increasing reported from extrusive carbonatite complexes world over; for e.g. Umbria and Latium, Central Italy, Abruzzo and Lucaniae, Southern Italy; Fort Portal and Katwe Kikorongo, Uganda; West Qinling, China; Campo de Calatrava, Spain, along with others. I am reporting here occurrence of pelletal and cored lapilli in the proximity of Amba Dongar carbonatite complex. The lapillus comprises of abundant phenocrysts of olivine, which are typically rimmed by dark brown thick coating. Such phenocrysts (oikocrysts) acquire remarkable roundedness, many of these show central circular fracture. Some of the phenocrysts are broken yet preserving their thick-brown rim. This feature is accentuated where such olivine oikocrysts are welded over groundmass mafics (typically clinorpyroxenes). However, most conspicuous thing is the presence of chrome spinel, which is dispersed as minor octahedra within the olivine, but not found in association with other minerals implying that olivine and chrome spinels are primary phases within the lapilli. There are other smaller droplets forming cored lapilli, which are dominantly composed of carbonates. Mineral chemistry of different phases indicate presence of forsteric (Fo89.20-67.34: Fa32.10-10.71: Tp0.46-0.04); chromium-rich spinel (Chromite55.34-24.86, Spinel31.88-10.16, Magnetite34.13-8.68, Mag. Chromite24.45-0.00, Ulvospinel23.21-0.00, Mag. Ulvospinel7.00-0.00, diopsidic clinopyroxene (Wo45.36-41.41: En40.92-50.60: Fs7.98-15.46), ilmenite (Il76.79-75.10:Ge13.08-14.60:Py1.72-1.08:He9.22-7.26), calcic-plagioclase (An69.36-47.90:Ab48.32- 29.27:Or3.78-1.37), and chlorite (ripidolite/brunsvigite). Discovery of pelletal and cored lapilli in the proximity of Amba Dongar carbonatite complex thus provide first direct evidence of the carbonated peridotitic mantle source for Amba Dongar carbonatites.
DS202007-1163
2019
Randive, K.R.Meshram, R.R., Dora, M.L., Naik, R., Shareef, M., Gopalakrishna, G., Moeshram, T., Baswani, S.R., Randive, K.R.A new find of calc-alkaline lamprophyres in Thanewasna area, western Bastar craton, India.Journal of Earth System Science, Vol. 128, 1, 7p. PdfIndiaminette

Abstract: Lamprophyre dykes within the granitoid and charnockite are reported for the first time from the Western Bastar Craton, Chandrapur district, Maharashtra. It shows porphyritic-panidiomorphic texture under a microscope, characterised by the predominance of biotite phenocrysts with less abundance of amphibole and clinopyroxene microphenocryst. The groundmass is composed more of K-feldspars over plagioclase, amphiboles, clinopyroxene, biotite, chlorite, apatite, sphene and magnetite. The mineral chemistry of biotite and magnesio-hornblende is indicative of minette variety of calc-alkaline lamprophyre (CAL), which is further supported by preliminary major oxides and trace element geochemistry. This unique association of CAL with granitoid provides an opportunity to study the spatio-temporal evolution of the lamprophyric magma in relation to the geodynamic perspective of the Bastar Craton.
DS202103-0413
2021
Randriamanjakahasina, O.Stoudmann, N., Reibelt, L.M., Rakotomalala, A.G., Randriamanjakahasina, O., Garcia, C.A., Waeber, P.O.A double edged sword: realities of artisanal and small scale mining for rural people in the Alaotra region of Madagascar. ** not specific to diamondsNatural Resources Forum, Vol 45 pp. 87-102. pdfAfrica, Madagascaralluvials

Abstract: A growing number of people are entering the artisanal and small-scale mining (ASM) sector worldwide. In Madagascar, millions of individuals depend on this informal activity. Through a case study in the Alaotra-Mangoro region of Madagascar, our research aimed to understand the "bottom-up" dynamics and ripple effects of the sector, by looking at the realities for rural communities where inhabitants are both directly and indirectly affected by ASM. We were interested in community members' and miners' perceptions of the socio-economic and environmental impacts of ASM, and in identifying the factors attracting people living in one of the country's agricultural hubs to this activity. Our results show a wide diversity of push and pull factors leading people to enter the sector. Although many positive impacts of ASM exist for miners and communities within the vicinity of mines, most miner participants considered themselves worse off since starting to mine, highlighting the high risk and low probability of return of ASM. ASM's potential for local and national development will remain squandered if its negative impacts continue to go unmanaged. Accounting for local contexts and the ripple effects of ASM will be crucial in achieving safety and security for miners, and to tap into the benefits it may offer communities while minimising environmental damage.
DS201412-0553
2014
Randrianandraisana, A.Martin, R.F., Randrianandraisana, A., Boulvais, P.Ampandrandava and similar phlogopite deposits in southern Madagascar: derivation from a silicocarbonatitic melt of crustal origin.Journal of African Earth Sciences, Vol. 94, pp. 111-118.Africa, MadagascarCarbonatite
DS2002-1759
2002
Ranero, C.Yanez, G., Cembrano, J., Pardo, M., Ranero, C., SellesThe Challinger Juan Fernadex Maipo major tectonic transition of the Nazca Andean subduction system 33-34Journal of South American Earth Sciences, Vol.15,1,Apr.pp.23-38.Chile, AndesSubduction, Geodynamic evidence and implications
DS200412-1543
2004
Ranero, C.R.Phipps Morgan, J., Reston, T.J., Ranero, C.R.Contemporaneous mass extinctions, continental flood basalts, and impact signals are mantle plume induced lithospheric gas explosEarth and Planetary Science Letters, Vol. 217, 3, Jan. 15, pp. 263-284.MantlePlume
DS2001-0568
2001
RanganaiKampunzu, A.B., Atekwana, McCourt, Tombale, RanganaiInteraction between Kaapvaal and Zimbabwe Cratons during the Neoarchean and implications for transition..Slave-Kaapvaal Workshop, Sept. Ottawa, 3p. abstractSouth Africa, ZimbabweArchean and post Archean plate tectonic styles, Limpopo Shashe belt
DS2000-0040
2000
Ranganai, R.T.Atekwana, E.A., Ranganai, R.T.Gravity and magnetic anomaly maps of the Limpopo Belt in southern Africa: implications for evolution KaapvaalGeological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-376.South Africa, ZimbabweGeophysics - gravity, magnetics, Craton - Kaapvaal, Zimbabwe
DS2000-0041
2000
Ranganai, R.T.Atekwana, E.A., Ranganai, R.T.Gravity and magnetic anomlay maps of the Limpopo Belt in southern Africa: implications for evolution KaapvaalGeological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-376.South Africa, ZimbabweGeophysics - gravity, magnetics, Craton - Kaapvaal, Zimbabwe
DS200812-0934
2008
Ranganai, R.T.Ranganai, R.T., Ebinger, C.J.Aeromagnetic and Land sat TM structural interpretation for identifying regional groundwater exploration targets, south central Zimbabwean Craton.Journal of Applied Geophysics, Vol. 65, 2, pp. 73-83.Africa, ZimbabweGeophysics
DS200812-0935
2008
Ranganai, R.T.Ranganai, R.T., Whaler, K.A., Ebinger, C.J.Gravity anomaly patterns in the south central Zimbabwe Archean Craton and their geological interpretation.Journal of African Earth Sciences, Vol. 51, 5, pp. 257-276.Africa, ZimbabweGeophysics - gravity
DS201602-0233
2016
Ranganai, R.T.Ranganai, R.T., Whaler, K.A., Ebinger, C.J.Aeromagnetic interpretation in the south-central Zimbabwe craton: (reappraisal of) crustal structure and tectonic implications.International Journal of Earth Sciences, in press available, 27p.Africa, ZimbabweGeophysics - magnetics

Abstract: Regional aeromagnetic data from the south-central Zimbabwe Craton have been digitally processed and enhanced for geological and structural mapping and tectonic interpretation integrated with gravity data, to constrain previous interpretations based on tentative geologic maps and provide new information to link these structural features to known tectonic events. The derived maps show excellent correlation between magnetic anomalies and the known geology, and extend lithological and structural mapping to the shallow/near subsurface. In particular, they reveal the presence of discrete crustal domains and several previously unrecognised dykes, faults, and ultramafic intrusions, as well as extensions to others. Five regional structural directions (ENE, NNE, NNW, NW, and WNW) are identified and associated with trends of geological units and cross-cutting structures. The magnetic lineament patterns cut across the >2.7 Ga greenstone belts, which are shown by gravity data to be restricted to the uppermost 10 km of the crust. Therefore, the greenstone belts were an integral part of the lithosphere before much of the upper crustal (brittle) deformation occurred. Significantly, the observed magnetic trends have representatives craton-wide, implying that our interpretation and inferences can be applied to the rest of the craton with confidence. Geological-tectonic correlation suggests that the interpreted regional trends are mainly 2.5 Ga (Great Dyke age) and younger, and relate to tectonic events including the reactivation of the Limpopo Belt at 2.0 Ga and the major regional igneous/dyking events at 1.8-2.0 Ga (Mashonaland), 1.1 Ga (Umkondo), and 180 Ma (Karoo). Thus, their origin is here inferred to be inter- and intra-cratonic collisions and block movements involving the Zimbabwe and Kaapvaal Cratons and the Limpopo Belt, and later lithospheric heating and extension associated with the break-up of Gondwana. The movements produced structures, or reactivated older fractures, that were exploited by Late Archaean and Proterozoic mafic intrusions. There was interplay between vertical and horizontal tectonics as seen in similar terrains worldwide.
DS201611-2134
2016
Ranganai, R.T.Ranganai, R.T., Whaler, K.A., Ebinger, C.J.Aeromagnetic interpretation in the south central Zimbabwe Craton: ( reappraisal of) crustal structure and tectonic implications.International Journal of Earth Sciences, Vol. 105, 8, pp. 2175-2201.Africa, ZimbabweGeophysics - gravity

Abstract: Regional aeromagnetic data from the south-central Zimbabwe Craton have been digitally processed and enhanced for geological and structural mapping and tectonic interpretation integrated with gravity data, to constrain previous interpretations based on tentative geologic maps and provide new information to link these structural features to known tectonic events. The derived maps show excellent correlation between magnetic anomalies and the known geology, and extend lithological and structural mapping to the shallow/near subsurface. In particular, they reveal the presence of discrete crustal domains and several previously unrecognised dykes, faults, and ultramafic intrusions, as well as extensions to others. Five regional structural directions (ENE, NNE, NNW, NW, and WNW) are identified and associated with trends of geological units and cross-cutting structures. The magnetic lineament patterns cut across the >2.7 Ga greenstone belts, which are shown by gravity data to be restricted to the uppermost 10 km of the crust. Therefore, the greenstone belts were an integral part of the lithosphere before much of the upper crustal (brittle) deformation occurred. Significantly, the observed magnetic trends have representatives craton-wide, implying that our interpretation and inferences can be applied to the rest of the craton with confidence. Geological-tectonic correlation suggests that the interpreted regional trends are mainly 2.5 Ga (Great Dyke age) and younger, and relate to tectonic events including the reactivation of the Limpopo Belt at 2.0 Ga and the major regional igneous/dyking events at 1.8-2.0 Ga (Mashonaland), 1.1 Ga (Umkondo), and 180 Ma (Karoo). Thus, their origin is here inferred to be inter- and intra-cratonic collisions and block movements involving the Zimbabwe and Kaapvaal Cratons and the Limpopo Belt, and later lithospheric heating and extension associated with the break-up of Gondwana. The movements produced structures, or reactivated older fractures, that were exploited by Late Archaean and Proterozoic mafic intrusions. There was interplay between vertical and horizontal tectonics as seen in similar terrains worldwide.
DS201612-2328
2016
Ranganai, R.T.Ranganai, R.T., Whaler, K.A., Ebinger, C.J.Aeromagnetic interpretation in the south central Zimbabwean Craton: (reappraisal of) crustal structure and tectonic implications.International Journal of Earth Sciences, Vol. 105, 8, pp. 2175-2201.Africa, ZimbabweGeophysics - magnetics

Abstract: Regional aeromagnetic data from the south-central Zimbabwe Craton have been digitally processed and enhanced for geological and structural mapping and tectonic interpretation integrated with gravity data, to constrain previous interpretations based on tentative geologic maps and provide new information to link these structural features to known tectonic events. The derived maps show excellent correlation between magnetic anomalies and the known geology, and extend lithological and structural mapping to the shallow/near subsurface. In particular, they reveal the presence of discrete crustal domains and several previously unrecognised dykes, faults, and ultramafic intrusions, as well as extensions to others. Five regional structural directions (ENE, NNE, NNW, NW, and WNW) are identified and associated with trends of geological units and cross-cutting structures. The magnetic lineament patterns cut across the >2.7 Ga greenstone belts, which are shown by gravity data to be restricted to the uppermost 10 km of the crust. Therefore, the greenstone belts were an integral part of the lithosphere before much of the upper crustal (brittle) deformation occurred. Significantly, the observed magnetic trends have representatives craton-wide, implying that our interpretation and inferences can be applied to the rest of the craton with confidence. Geological-tectonic correlation suggests that the interpreted regional trends are mainly 2.5 Ga (Great Dyke age) and younger, and relate to tectonic events including the reactivation of the Limpopo Belt at 2.0 Ga and the major regional igneous/dyking events at 1.8-2.0 Ga (Mashonaland), 1.1 Ga (Umkondo), and 180 Ma (Karoo). Thus, their origin is here inferred to be inter- and intra-cratonic collisions and block movements involving the Zimbabwe and Kaapvaal Cratons and the Limpopo Belt, and later lithospheric heating and extension associated with the break-up of Gondwana. The movements produced structures, or reactivated older fractures, that were exploited by Late Archaean and Proterozoic mafic intrusions. There was interplay between vertical and horizontal tectonics as seen in similar terrains worldwide.
DS201801-0062
2017
Rangarajan, G.Shitole, A., Sant, D.A., Parvez, I.A., Rangarajan, G., Patel, S., Viladkar, S.G., Murty, A.S.N., Kumari, G.Shallow seismic studies along Amba Dongar to Sinhada ( longitude 74 3 50E) transect, western India.Carbonatite-alkaline rocks and associated mineral deposits , Dec. 8-11, abstract p. 16.Indiadeposit - Amba Dongar

Abstract: The microtremor method is applied to map subsurface rheological boundaries (stratigraphic, faults and plutons) is based on strong acoustic impedance across contrasting density of rock/ sediment/ weathered interfaces up to shallow depths along longitude 74° 3'50" E from village Amba Dongar (latitude: 21° 59'N) up to Sinhada village (latitude: 22° 14' N). The 30 km long transect exposes variety of rocks viz., unclassified granite gneisses and metasediments (Precambrian age); sediments belonging to Bagh Group (Late Cretaceous); alkaline - carbonatite plutons and lava flows belonging to Deccan Traps (Late Cretaceous). In all, sixty stations were surveyed along the longitude 74° 3'50" E with spacing of 500 m. H/V spectral ratio technique reveals four rheological interfaces identified by resonant frequencies (fr) ranges 0.2213 to 0.7456 Hz (L1), 1.0102 to 3.076 Hz (L2), 4.8508 to 21.0502 Hz (L3), and 24.5018 to 27.1119 Hz (L4). L1 represents interface between plutons, Precambrian basement rocks; L2 represents interface between Bagh sediments, Deccan Traps and intrusives whereas L3 and L4 captures depth of top most weathered profile. We estimate the depth range for L1 L2 L3 and L4 using equation (h = 110.18fr-1.97) derived based on Deep Banni Core (1764 m deep from surface: DGH record). Deep Banni Core has a distinct interface between Mesozoic rocks and Precambrian basement. The depths are further compared with terrain-based equation. Further, the overall results from the present study are compared with seismic refraction studies along Phangia-Kadipani (NGRI Technical Report, 2003). The subsurface profile across longitude 74° 3'50" E educe faults that bound Bagh Group of rocks with Deccan Trap and Precambrian. We identify two plutons underneath three zones of intrusive viz., Amba Dongar Carbonatite Complex (Station 1 to 8), Tiloda Alkaline (station 33 to 44) and Rumadia Alkaline (station 46 to 51). The present study demarcates the presence of depression over Amba Dongar hill (station 1 to 3), filled by post carbonatite basalt earlier reported by Viladkar et al., (1996 and 2005) suggesting caldera morphology. Similarly, studies identify intrusive-pluton interfaces one, below the Amba Dongar hill, and second between village Tiloda and Rumadia at depth of ~500 m from the surface. Microtremor survey further depicts both basement morphology and thickness of Bagh Group and Deccan Traps.
DS1900-0698
1908
Range, P.Range, P.Dwykakonglomerat in Deutsch Suedwest AfrikaZeitschr. Deut. Geol. Ges., Vol. 60, No. 3, PP. 64-66.Southwest Africa, NamibiaGeology
DS1900-0794
1909
Range, P.Range, P.Die Diamant felder Bei LuderitzbuchtDeut. Kolonialblatt., Vol. 20, No. 22, PP. 1039-1048; MAP 1: 800, 000.Southwest Africa, NamibiaGeology, Marine Diamond Placers
DS1900-0795
1909
Range, P.Range, P.Die Geologischen Formationen des NamalandesMon. Ber.. Deutsch. Geol. Ges. Berlin., Vol. 61, PT. 2, PP. 120-130.Southwest Africa, NamibiaStratigraphy, Brukkaros
DS1910-0086
1910
Range, P.Range, P.Zur Geologie des NamalandesMonatsb. Deutsch. Geol. Ges. Berlin., PP. 462-468.Southwest Africa, NamibiaGeology
DS1910-0087
1910
Range, P.Range, P.Sketch of the Geology of German NamaqualandGeological Society of South Africa Transactions, Vol. 13, PP. 1-9.Southwest Africa, NamibiaRegional Geology, Brukkaros
DS1910-0088
1910
Range, P.Range, P.Diamant vorkommen in den Vereinigten Staetten von AmerikaDeut. Kolonialblatt., Vol. 21, PP. 942-943.United States, Gulf Coast, ArkansasDiamond Occurrence
DS1910-0207
1911
Range, P.Range, P.Das LuederitzlandMitt. Deutsch. Schutzgeb., Vol. 24, No. 1, PP. 30-42.Southwest Africa, NamibiaGeology
DS1910-0302
1912
Range, P.Range, P.Geologie des Deutschen NamalandesBeitr. Geol. Erf. Deut. Schutzgeb., Vol. 2, 104P.; MAP 1:2, 000, 000.Southwest Africa, NamibiaRegional, Geology, Kimberley, Janlib
DS1910-0372
1913
Range, P.Range, P.Meteoriten aus Deutsch SuedwestafrikaMitt. Deutsch. Schutzgeb., Vol. 26, No. 4, PP. 341-343.Southwest Africa, NamibiaMeteorite
DS1910-0471
1915
Range, P.Range, P.Geitsi Gubib, an Old VolcanoRoyal Society. STH. AFR. Transactions, Vol. 5, PP. 247-257.Southwest Africa, NamibiaDiamond, Kimberlite, Carbonatite, Geomorphology
DS1920-0169
1923
Range, P.Range, P.Die Diamant vorkommen der ErdeZeitschr. F. Prakt. Geol., Vol. 31, PP. 49-55; P. 65.South Africa, Global, Southwest Africa, NamibiaDiamond Occurrences
DS1920-0294
1926
Range, P.Range, P.Die Diamant lagerstatten AfrikasKol. Rundschau (berlin), Vol. 18, No. 1, PP. 17-19.South Africa, West Africa, East Africa, Southwest Africa, NamibiaDiamond Occurrences
DS1920-0463
1929
Range, P.Range, P.Die Diamant vorkommen in Klein-namaqualandUebersee And Kolonial Zeitung, No. 8, P. 154.South Africa, Namaqualand CoastDiamond Occurrences
DS1920-0464
1929
Range, P.Range, P.Die Neuendeckten Diamantefelder in Klein NamaqualandSteinbr. Sandgr., Vol. 33, PP. 517-519.South Africa, Namaqualand CoastDiamond Occurrences
DS1930-0226
1936
Range, P.Range, P.Mineral funde und Bergbau in Den Deutschen Schutzgebieten In afrika und in der Suedsee.Kolon. Rundschau, Vol. 27, No. 3, PP. 196-209.Southwest Africa, NamibiaDiamond Occurrences
DS201708-1741
2017
Ranger, I.Ranger, I.Punctuated long lived emplacement history of kimberlites from the Renard cluster, Superior Province, Canada indicated by new high precision U-Pb groundmass perovskite dating.11th. International Kimberlite Conference, OralCanada, Quebecdeposit - Renard
DS201810-2370
2018
Ranger, I.M.Ranger, I.M., Heaman, L.M., Pearson, D.G., Muntener, C., Zhuk, V.Punctuated, long lived emplacement history of the Renard 2 kimberlite, Canada, revealed by new high precision U-Pb groundmass perovskite dating. IF-TIMSMineralogy and Petrology, doi.org/101007/ s00710-018-0629-0 13p.Canada, Quebecdeposit - Renard

Abstract: Kimberlites are rare volatile-rich ultramafic magmas thought to erupt in short periods of time (<1 Myr) but there is a growing body of evidence that the emplacement history of a kimberlite can be significantly more protracted. In this study we report a detailed geochronology investigation of a single kimberlite pipe from the Renard cluster in north-central Québec. Ten new high precision ID-TIMS (isotope dilution - thermal ionization mass spectrometry) U-Pb groundmass perovskite dates from the main pipe-infilling kimberlites and several small hypabyssal kimberlites from the Renard 2 pipe indicate kimberlite magmatism lasted at least ~20 Myr. Two samples of the main pipe-infilling kimberlites yield identical weighted mean 206Pb/238U perovskite dates with a composite date of 643.8?±?1.0 Myr, interpreted to be the best estimate for main pipe emplacement. In contrast, six hypabyssal kimberlite samples yielded a range of weighted mean 206Pb/238U perovskite dates between ~652-632 Myr. Multiple dates determined from these early-, syn- and late-stage small hypabyssal kimberlites in the Renard 2 pipe demonstrate this rock type (commonly used to date kimberlites) help to constrain the duration of kimberlite intrusion history within a pipe but do not necessarily reliably record the emplacement age of the main diatreme in the Renard cluster. Our results provide the first robust geochronological data on a single kimberlite that confirms the field relationships initially observed by Wagner (1914) and Clement (1982); the presence of antecedent (diatreme precursor) intrusions, contemporaneous (syn-diatreme) intrusions, and consequent (post-diatreme) cross-cutting intrusions. The results of this detailed U-Pb geochronology study indicate a single kimberlite pipe can record millions of years of magmatism, much longer than previously thought from the classical viewpoint of a rapid and short-duration emplacement history.
DS1994-0788
1994
Rangin, C.Huchon, P., Le Pichon, X., Rangin, C.Indochin a Peninsula and the collision of India and EurasiaGeology, Vol. 22, No. 1, January pp. 27-30China, IndiaTectonics, Deformation
DS1994-0789
1994
Rangin, C.Huchon, P., Le Pichon, X., Rangin, C.Indochin a Peninsula and the collision of India and EurasiaGeology, Vol. 22, No. 1, January pp. 27-30.China, IndiaTectonics, Deformation
DS202107-1101
2018
Rani, K.Guha, A., Rani, K., Varma, C.B., Sarwate, N.K., Sharma, N., Mukherjee, A., Kumar, K.V., Pal, S.K., Saw, A.K., Jha, S.K.Identification of potential zones for kimberlite exploration - an Earth observation approach. ChhatarpurThe International Achives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. XLII-5 12p. PdfIndia, Madhya PradeshASTER, lineament

Abstract: In the present study, we have prepared the thematic evidence layers for identifying the potential zones of kimberlite emplacement in parts of Chhatarpur district, Madhya Pradesh. These thematic layers or evidence layers are geological structure, alteration zones, lineament density, surface alteration and geomorphic anomaly and these layers are prepared from the remote sensing data. As orientation of the geological structures (i.e fault system) and their density have the major role in the emplacement of kimberlite; both of these evidence layers are integrated using "AND" Boolean Logical Operator. On the other hand, two evidential layers regarded as the proxy to indicate the "surface expressions on kimberlite (i.e. alteration zones and geomorphic anomaly) are combined using "OR" operator as either of these two surface expression is indicative of kimberlite. Consequently, conjugate evidence layers on the surface expressions of kimberlite are integrated with the causative evidence layers of kimberlite emplacement using "AND" operator to identify the potential zones of diamond occurrences. Potential zones of kimberlite are overlaid on the residual gravity anomaly map derived from space-based gravity model of European Improved Gravity of Earth by New Technique (EIGEN6C4) to relate potential zones of kimberlite with the similar structural alignment (delineated in the residual gravity map) of known occurrence of kimberlite. We also have carried out indicator mineral survey around these potential zones and some of the kimberlite specific indicator minerals are identified in the stream sediments within these potential zones.
DS2002-1306
2002
Raniengar, A.S.Raniengar, A.S.Carbonatite bodies of Dhanota Dkancholi area, Mahendragarh district HaryanaJournal of the Geological Society of India, Vol. 60, 5, Nov., pp. 587-92.IndiaBlank
DS200412-1620
2002
Raniengar, A.S.Raniengar, A.S.Carbonatite bodies of Dhanota Dkancholi area, Mahendragarh district Haryana.Journal of the Geological Society of India, Vol. 60, 5, Nov., pp. 587-92.IndiaCarbonatite
DS201012-0753
2010
Ranjan, P.Stanley, C.R., O'Driscoll, N., Ranjan, P.Determining the magnitude of true analytical error in geochemical analysis.Geochemistry: Exploration, Environment, Analysis, Vol. 10, 4, pp. 355-364.TechnologyGeochemistry - not specific to diamonds
DS201709-2067
2017
Ranjan, S.Upadhyay, D., Ranjan, S., Abhinay, K., Pruseth, K.L., Nanda, J.K.India-Antarica connection: constraints from deformed alkaline rocks and carbonatites.Goldschmidt Conference, abstract 1p.Indiacarbonatites

Abstract: Deformed Alkaline Rocks and Carbonatites (DARCs) are markers of suture zones where continents have rifted apart and later amalgamated [1]. Petrological and geochronological data indicates that parts of India and East Antarctica may have been involved in several episodes of collision and breakup during the assembly of past supercontinents [2]. DARCs at the eastern margin of the Eastern Ghats Province (EGP) in India preserve the record of these amalgamation and breakup events. It is thought that the Napier Complex of East Antarctica collided with the Dharwar Craton of India at ca. 1.60 Ga forming the central and eastern Indian shield [3]. New zircon U-Pb ages from DARCs at the EGP margin show that the alkaline complexes (Kamakhyanagar: 1350±14 Ma Rairakhol: 1379±6 Ma; Khariar: 1478±5 Ma; Koraput: 1387±34 Ma; Kunavaram: 1360±5 Ma; Jojuru: 1352±6 Ma) were emplaced in a narrow time interval. The alkaline magmatism marks an episode of rifting in the Indo-Antarctic continental fragment, correlatable with breakup of the Columbia supercontinent. Metamorphic zircon from the alkaline rocks furnish age populations at 917-950 Ma, 792- 806 Ma and 562-569 Ma. The 917-950 Ma ages are correlated with the closure of an oceanic basin between the Ruker Terrane of East Antarctica and the Indian Shield during the assembly of the Rodinia supercontinent. This led to the collision of the Ruker Terrane with the combined India-Napier Complex producing the Grenville-age EGPRayner Complex orogen [2, 3]. The 792-806 Ma ages record the disintegration of Rodinia when Greater India started to break away from East Antarctica [4]. In the early Paleozoic, India reconverged towards Antarctica and Australia during Gondwanaland assembly. The 562-569 Ma zircon ages date the resulting collisions during Pan-African orogenesis.
DS201710-2272
2017
Ranjan, S.Upadhyay, D., Ranjan, S., Abhinay, K., Pruseth, K.L., Nanda, J.K.India-Antarctica connection: constraints from deformed alkaline rocks and carbonatites.Goldschmidt Conference, 1p. AbstractIndiacarbonatites

Abstract: Re-Os and platinum group element analyses are reported for peridotite xenoliths from the 533 Ma Venetia kimberlite cluster situated in the Limpopo Mobile Belt, the Neoarchaean collision zone between the Kaapvaal and Zimbabwe Cratons. The Venetian xenoliths provide a rare opportunity to examine the state of the cratonic lithosphere prior to major regional metasomatic disturbance of Re-Os systematics throughout the Phanerozoic. The 32 studied xenoliths record Si-enrichment that is characteristic of the Kaapvaal lithospheric mantle and can be subdivided into five groups based on Re-Os analyses. The most pristine group I samples (n = 13) display an approximately isochronous relationship and fall on a 3.28 ± 0.17 Ga (95 % conf. int.) reference line that is based on their mean TMA age. This age overlaps with the formation age of the Limpopo crust at 3.35-3.28 Ga. The group I samples derive from ~50 to ~170 km depth, suggesting coeval melt depletion of the majority of the Venetia lithospheric mantle column. Group II and III samples have elevated Re/Os due to Re addition during kimberlite magmatism. Group II has otherwise undergone a similar evolution as the group I samples with overlapping 187Os/188Os at eruption age: 187Os/188OsEA, while group III samples have low Os concentrations, unradiogenic 187Os/188OsEA and were effectively Re-free prior to kimberlite magmatism. The other sample groups (IV and V) have disturbed Re-Os systematics and provide no reliable age information. A strong positive correlation is recorded between Os and Re concentrations for group I samples, which is extended to groups II and III after correction for kimberlite addition. This positive correlation precludes a single stage melt depletion history and indicates coupled remobilisation of Re and Os. The combination of Re-Os mobility, preservation of the isochronous relationship, correlation of 187Os/188Os with degree of melt depletion and lack of radiogenic Os addition puts tight constraints on the formation and subsequent evolution of Venetia lithosphere. First, melt depletion and remobilisation of Re and Os must have occurred within error of the 3.28 Ga mean TMA age. Second, the refractory peridotites contain significant Re despite recording >40 % melt extraction. Third, assuming that Si-enrichment and Re-Os mobility in the Venetia lithospheric mantle were linked, this process must have occurred within ~100 Myr of initial melt depletion in order to preserve the isochronous relationship. Based on the regional geological evolution, we propose a rapid recycling model with initial melt depletion at ~3.35 Ga to form a tholeiitic mafic crust that is recycled at ~3.28 Ga, resulting in the intrusion of a TTG suite and Si-enrichment of the lithospheric mantle. The non-zero primary Re contents of the Venetia xenoliths imply that TRD model ages significantly underestimate the true depletion age even for highly depleted peridotites. The overlap of the ~2.6 Ga TRD ages with the time of the Kaapvaal-Limpopo collision is purely fortuitous and has no geological significance. Hence, this study underlines the importance of scrutiny if age information is to be derived from whole rock Re-Os analyses.
DS201902-0264
2019
Ranjan, S.Chakraborty, T., Upadhyay, D., Ranjan, S., Pruseth, K.L., Nanda, J.K.The geological evolution of the Gangpur schist belt, eastern India: constraints on the formation of the greater Indian landmass of the Proterozoic.Journal of Metamorphic Geology, Vol. 37, 1, pp. 113-151.Indiageology

Abstract: The Central Indian Tectonic Zone (CITZ) is a Proterozoic suture along which the Northern and Southern Indian Blocks are inferred to have amalgamated forming the Greater Indian Landmass. In this study, we use the metamorphic and geochronological evolution of the Gangpur Schist Belt (GSB) and neighbouring crustal units to constrain crustal accretion processes associated with the amalgamation of the Northern and Southern Indian Blocks. The GSB sandwiched between the Bonai Granite pluton of the Singhbhum craton and granite gneisses of the Chhotanagpur Gneiss Complex (CGC) links the CITZ and the North Singhbhum Mobile Belt. New zircon age data constrain the emplacement of the Bonai Granite at 3,370 ± 10 Ma, while the magmatic protoliths of the Chhotanagpur gneisses were emplaced at c. 1.65 Ga. The sediments in the southern part of the Gangpur basin were derived from the Singhbhum craton, whereas those in the northern part were derived dominantly from the CGC. Sedimentation is estimated to have taken place between c. 1.65 and c. 1.45 Ga. The Upper Bonai/Darjing Group rocks of the basin underwent major metamorphic episodes at c. 1.56 and c. 1.45 Ga, while the Gangpur Group of rocks were metamorphosed at c. 1.45 and c. 0.97 Ga. Based on thermobarometric studies and zircon-monazite geochronology, we infer that the geological history of the GSB is similar to that of the North Singhbhum Mobile Belt with the Upper Bonai/Darjing and the Gangpur Groups being the westward extensions of the southern and northern domains of the North Singhbhum Mobile Belt respectively. We propose a three-stage model of crustal accretion across the Singhbhum craton - GSB/North Singhbhum Mobile Belt - GC contact. The magmatic protoliths of the Chhotanagpur Gneisses were emplaced at c. 1.65 Ga in an arc setting. The earliest accretion event at c. 1.56 Ga involved northward subduction and amalgamation of the Upper Bonai Group with the Singhbhum craton followed by accretion of the Gangpur Group with the Singhbhum craton-Upper Bonai Group composite at c. 1.45 Ga. Finally, continent-continent collision at c. 0.96 Ga led to the accretion of the CGC with the Singhbhum craton-Upper Bonai Group-Gangpur Group crustal units, synchronous with emplacement of pegmatitic granites. The geological events recorded in the GSB and other units of the CITZ only partially overlap with those in the Trans North China Orogen and the Capricorn Orogen of Western Australia, indicating that these suture zones are not correlatable.
DS202107-1092
2021
Rankenburg, K.Brennan, D.T., Li, Z-X., Rankenburg, K., Evans, N., Link, P.K.Recalibrating Rodinian rifting in the northwestern United States.Geology Today, Vol. 49, pp. 617-622.United States, Washingtongeochronology

Abstract: A lack of precise age constraints for Neoproterozoic strata in the northwestern United States (Washington State), including the Buffalo Hump Formation (BHF), has resulted in conflicting interpretations of Rodinia amalgamation and breakup processes. Previous detrital zircon (DZ) studies identified a youngest ca. 1.1 Ga DZ age population in the BHF, interpreted to reflect mostly first-cycle sourcing of unidentified but proximal magmatic rocks intruded during the amalgamation of Rodinia at ca. 1.0 Ga. Alternatively, the ca. 1.1 Ga DZ population has been suggested to represent a distal source with deposition occurring during the early phases of Rodinia rifting, more than 250 m.y. after zircon crystallization. We combined conventional laser-ablation split-stream analyses of U-Pb/Lu-Hf isotopes in zircon with a method of rapid (8 s per spot) U-Pb analysis to evaluate these opposing models. Our study of ~2000 DZ grains from the BHF identified for the first time a minor (~1%) yet significant ca. 760 Ma population, which constrains the maximum depositional age. This new geochronology implies that the BHF records early rift deposition during the breakup of Rodinia and correlates with sedimentary rocks found in other late Tonian basins of southwestern Laurentia.
DS201706-1076
2017
Rankey, E.C.Harmon, R.S., Hark, R.R., Throckmorton, C.S., Rankey, E.C., Wise, M.A., Somers, A.M., Collins, L.M.Geochemical fingerprinting by handheld laser-induced breakdown spectroscopy. (LIBS)Geostandards and Geoanalytical Research, in press availableTechnologyspectroscopy

Abstract: A broad suite of geological materials were studied a using a handheld laser-induced breakdown spectroscopy (LIBS) instrument. Because LIBS is simultaneously sensitive to all elements, the full broadband emission spectrum recorded from a single laser shot provides a ‘chemical fingerprint’ of any material - solid, liquid or gas. The distinguishing chemical characteristics of the samples analysed were identified through principal component analysis (PCA), which demonstrates how this technique for statistical analysis can be used to identify spectral differences between similar sample types based on minor and trace constituents. Partial least squares discriminant analysis (PLSDA) was used to distinguish and classify the materials, with excellent discrimination achieved for all sample types. This study illustrates through four selected examples involving carbonate minerals and rocks, the oxide mineral pair columbite-tantalite, the silicate mineral garnet and native gold how portable, handheld LIBS analysers can be used as a tool for real-time chemical analysis under simulated field conditions for element or mineral identification plus such applications as stratigraphic correlation, provenance determination and natural resources exploration.
DS1989-1253
1989
Rankin, A.H.Rankin, A.H.Fluid inclusions.An overview and layman's outline of what info they mayprovideGeology Today, Vol. 5, No. 1, Jan-Feb. pp. 21-24. Database # 17728GlobalFluid Inclusions, Ore genesis
DS1994-1781
1994
Rankin, A.H.Ting, W., Burke, E.A.J., Rankin, A.H., Woolley, A.R.The characterization and petrogenetic significance of CO2, H2O and CH4fluid inclusions in apatite SukuluEuropean Journal of Mineralogy, No. 6, pp. 787-804.UgandaCarbonatite, Deposit -Sukulu
DS1994-1782
1994
Rankin, A.H.Ting, W., Rankin, A.H., Woolley, A.R.Petrogenetic significance of solid carbonate inclusions in apatite of the Sukulu carbonatite, Uganda.Lithos, Vol. 31, No. 3-4, January pp. 177-188.UgandaCarbonatite, Apatite, Deposit -Sukulu
DS1996-1540
1996
Rankin, A.H.Wilkinson, J.J., Nolan, J., Rankin, A.H.Silicothermal fluid: a novel medium for mass transport in the lithosphereGeology, Vol. 24, No. 12, Dec. pp. 1059-62MantleFluid flow
DS1998-1181
1998
Rankin, A.H.Potter, J., Rankin, A.H., NI, P.A preliminary study of methane inclusions in alkaline igneous rocks of Kola igneous Province: implications...Eur. Journal of Mineralogy, Vol. 10, No. 6, Nov. 1, pp. 1167-80.Russia, Kola PeninsulaAlkaline rocks, Methane
DS1999-0099
1999
Rankin, A.H.Buhn, B., Rankin, A.H.Geochemistry and ore forming potential of alkali and volatile rich carbonatite magmas.Stanley, SGA Fifth Biennial Symposium, pp. 623-6.GlobalMagma, Carbonatite
DS1999-0564
1999
Rankin, A.H.Potter, J., Rankin, A.H., Treloar, P.J.The relationship between CH4 and CO2 inclusions and iron O S mineralization in intrusions Kola alkaline provinceStanley, SGA Fifth Biennial Symposium, pp. 87-90.Russia, Kola PeninsulaAlkaline rocks, Geochronology
DS2002-0218
2002
Rankin, A.H.Buhn, B., Rankin, A.H., Schneider, J., Dulski, P.The nature of orthomagmatic, carbonatitic fluids precipitating REE Sr rich flourite, fluid inclusion...Chemical Geology, Vol.186,1-2, pp. 75-98., Vol.186,1-2, pp. 75-98.NamibiaGeochronology - fluorite, Deposit - Okorusu
DS2002-0219
2002
Rankin, A.H.Buhn, B., Rankin, A.H., Schneider, J., Dulski, P.The nature of orthomagmatic, carbonatitic fluids precipitating REE Sr rich flourite, fluid inclusion...Chemical Geology, Vol.186,1-2, pp. 75-98., Vol.186,1-2, pp. 75-98.NamibiaGeochronology - fluorite, Deposit - Okorusu
DS200512-0868
2004
Rankin, A.H.Potter, J., Rankin, A.H., Treloar, P.J.Abiogenic Fischer-Topsch synthesis of hydrocarbons in alkaline igneous rocks: fluid inclusions, textural and isotopic evidence from the Lovozero complex, NW Russia.Lithos, Vol. 75, 3-4, pp. 311-358.RussiaAlkalic
DS200612-0114
2006
Rankin, A.H.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
DS201012-0297
2010
Rankin, A.H.Humprhreys, E.R., Bailey, K., Hawkesworth, C.J., Wall, F., Najorka, J., Rankin, A.H.Aragonite in olivine from Calatrava, Spain - evidence for mantle carbonatite melts from > 100km depth.Geology, Vol. 38, 10, pp. 911-914.Europe, SpainCarbonatite
DS201802-0231
2017
Rankin, A.H.Dowman, E., Wall, F., Treloar, P.J., Rankin, A.H.Rare earth mobility as a result of multiple phases of fluid activity in fenite around the Chilwa Island carbonatite, Malawi.Mineralogical Magazine, Vol. 81, 6, pp. 1367-1395.Africa, Malawicarbonatite - Chilwa

Abstract: Carbonatites are enriched in critical raw materials such as the rare earth elements (REE), niobium, fluorspar and phosphate. A better understanding of their fluid regimes will improve our knowledge of how to target and exploit economic deposits. This study shows that multiple fluid phases penetrated the surrounding fenite aureole during carbonatite emplacement at Chilwa Island, Malawi. The first alkaline fluids formed the main fenite assemblage and later microscopic vein networks contain the minerals of potential economic interest such as pyrochlore in high-grade fenite and RE minerals throughout the aureole. Seventeen samples of fenite rock from the metasomatic aureole around the Chilwa Island carbonatite complex were chosen for study (Natural History Museum, London collection BM1968 P37). In addition to the main fenite assemblage of feldspar and aegirine ± arfvedsonite, riebeckite and richterite, the fenite contains micro-mineral assemblages including apatite, ilmenite, rutile, magnetite, zircon, RE minerals and pyrochlore in vein networks. Petrography using SEM-EDX showed that the RE minerals (monazite, bastnäsite and parisite) formed later than the fenite feldspar, aegirine and apatite and provide evidence of REE mobility into all grades of fenite. Fenite apatite has a distinct negative Eu anomaly (determined by LA-ICP-MS) that is rare in carbonatite-associated rocks and interpreted as related to pre-crystallisation of plagioclase and co-crystallisation with K-feldspar in the fenite. The fenite minerals have consistently higher mid REE/light REE ratios (La/Sm = ~1.3 monazite, ~1.9 bastnäsite, ~1.2 parisite) than their counterparts in the carbonatites (La/Sm = ~2.5 monazite, ~4.2 bastnäsite, ~3.4 parisite). Quartz in the low- and medium-grade fenite hosts fluid inclusions, typically a few µm in diameter, secondary and extremely heterogeneous. Single phase, 2- and 3-phase, single solid and multi solid-bearing examples are present, with 2-phase the most abundant. Calcite, nahcolite, burbankite and barite were found in the inclusions. Decrepitation of inclusions occurred at around 200°C before homogenisation but melting temperature data indicate that the inclusions contain relatively pure CO2. A minimum salinity of around 24 wt.% NaCl equivalent was determined. Among the trace elements in whole rock analyses, enrichment in Ba, Mo, Nb, Pb, Sr, Th and Y and depletion in Co, Hf and V are common to carbonatite and fenite but enrichment in carbonatitic type elements (Ba, Nb, Sr, Th, Y, and REE) generally increases towards the inner parts of the aureole. A schematic model contains multiple fluid events, related to first and second boiling of the magma, accompanying intrusion of the carbonatites at Chilwa Island, each contributing to the mineralogy and chemistry of the fenite. The presence of distinct RE mineral micro-assemblages in fenite at some distance from carbonatite could be developed as an exploration indicator of REE enrichment.
DS201803-0444
2017
Rankin, A.H.Dowman, E., Wall, F., Treloar, P.J., Rankin, A.H.Rare earth mobility as a result of multiple phases of fluid activity in fenite around the Chilwa Island carbonatite, Malawi.Mineralogical Magazine, Vol. 81, 6, pp. 1367-1395.Africa, Malawicarbonatite

Abstract: Carbonatites are enriched in critical raw materials such as the rare earth elements (REE), niobium, fluorspar and phosphate. A better understanding of their fluid regimes will improve our knowledge of how to target and exploit economic deposits. This study shows that multiple fluid phases penetrated the surrounding fenite aureole during carbonatite emplacement at Chilwa Island, Malawi. The first alkaline fluids formed the main fenite assemblage and later microscopic vein networks contain the minerals of potential economic interest such as pyrochlore in high-grade fenite and RE minerals throughout the aureole. Seventeen samples of fenite rock from the metasomatic aureole around the Chilwa Island carbonatite complex were chosen for study (Natural History Museum, London collection BM1968 P37). In addition to the main fenite assemblage of feldspar and aegirine ± arfvedsonite, riebeckite and richterite, the fenite contains micro-mineral assemblages including apatite, ilmenite, rutile, magnetite, zircon, RE minerals and pyrochlore in vein networks. Petrography using SEM-EDX showed that the RE minerals (monazite, bastnäsite and parisite) formed later than the fenite feldspar, aegirine and apatite and provide evidence of REE mobility into all grades of fenite. Fenite apatite has a distinct negative Eu anomaly (determined by LA-ICP-MS) that is rare in carbonatite-associated rocks and interpreted as related to pre-crystallisation of plagioclase and co-crystallisation with K-feldspar in the fenite. The fenite minerals have consistently higher mid REE/light REE ratios (La/Sm = ~1.3 monazite, ~1.9 bastnäsite, ~1.2 parisite) than their counterparts in the carbonatites (La/Sm = ~2.5 monazite, ~4.2 bastnäsite, ~3.4 parisite). Quartz in the low- and medium-grade fenite hosts fluid inclusions, typically a few µm in diameter, secondary and extremely heterogeneous. Single phase, 2- and 3-phase, single solid and multi solid-bearing examples are present, with 2-phase the most abundant. Calcite, nahcolite, burbankite and barite were found in the inclusions. Decrepitation of inclusions occurred at around 200°C before homogenisation but melting temperature data indicate that the inclusions contain relatively pure CO2. A minimum salinity of around 24 wt.% NaCl equivalent was determined. Among the trace elements in whole rock analyses, enrichment in Ba, Mo, Nb, Pb, Sr, Th and Y and depletion in Co, Hf and V are common to carbonatite and fenite but enrichment in carbonatitic type elements (Ba, Nb, Sr, Th, Y, and REE) generally increases towards the inner parts of the aureole. A schematic model contains multiple fluid events, related to first and second boiling of the magma, accompanying intrusion of the carbonatites at Chilwa Island, each contributing to the mineralogy and chemistry of the fenite. The presence of distinct RE mineral micro-assemblages in fenite at some distance from carbonatite could be developed as an exploration indicator of REE enrichment.
DS1960-1155
1969
Rankin, D.Loftus, W.K.B., Stucke, H.J., Rankin, D.Mining and Treatment Plant Practice at the Finsch MineSouth African Institute of Mining and Metallurgy. Journal, Vol. 69, No. 8, PP. 364-407.South AfricaDiamond Mining Recovery, Kimberlite Pipes
DS1990-1214
1990
Rankin, D.Rankin, D., Pascal, F.A gap in the North American central plains conductivity anomalyPhysics of the Earth and Planetary Interiors, Vol. 60, pp. 132-137MidcontinentGeophysics, Paleotectonics
DS1983-0529
1983
Rankin, D.W.Rankin, D.W., Stern, T.W., Mclelland, J., Zartman, R.E., Odom, A.Correlation Chart for Precambrian Rocks of the Eastern United States.United States Geological Survey (USGS) PROF. PAPER., No. 1241-E, 18P.GlobalMid-continent
DS1993-1285
1993
Rankin, D.W.Reed, J.C., Bickford, M.E., Houston, R.S., Link, P.K., Rankin, D.W.Precambrian: conterminous U.SGeological Society of America DNAG Volume, No. C-2, 700p. approx. $ 100.00United StatesBook -table of contents, Precambrian
DS200612-0577
2006
Rankin, D.W.Hibbard, J.P., Van Staal, C.R., Rankin, D.W., Williams, H.Lithotectonic map of the Appalachian orogen, Canada-United States of America.Geological Survey of Canada, Map 2096A 1: 1,500,000 $ 30.00Canada, United StatesMap - tectonics
DS201312-0431
2013
Rankin, L.Isles, D., Rankin, L.Geological interpretation of aeromagnetic data.Ebook, approx. $ 100.TechnologyGeophysics - aeromag not specific to diamonds but interest
DS2003-0303
2003
Rankin, L.R.Crowe, W.A., Nash, C.R., Harris, L.B., Leeming, P.M., Rankin, L.R.The geology of the Rengali province: implications for the tectonic development ofJournal of Asian Earth Sciences, Vol. 21, 7, pp. 697-710.IndiaTectonics - not specific to diamonds
DS200412-0390
2003
Rankin, L.R.Crowe, W.A., Nash, C.R., Harris, L.B., Leeming, P.M., Rankin, L.R.The geology of the Rengali province: implications for the tectonic development of northern Orissa, India.Journal of Asian Earth Sciences, Vol. 21, 7, pp. 697-710.IndiaTectonics - not specific to diamonds
DS1986-0861
1986
Rankin, R.A.Willett, G.C., Duncan, R.K., Rankin, R.A.Geology and economic evaluation of the Mt. Weld carbonatite,Laverton Western Australia #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 97-99AustraliaCarbonatite
DS1989-1628
1989
Rankin, R.A.Willett, G.C., Duncan, R.K., Rankin, R.A.Geology and economic evaluation of the Mt. Weldcarbonatite, Laverton Western Australia #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 1215-1238AustraliaCarbonatite, Mt. Weld
DS2000-0793
2000
Ranneli, G.Ranneli, G., Pellegrini, R., D'Offizi, S.Time dependence of negative bouyancy and the subduction of continental lithosphere.Journal of Geodynm., Vol. 30, No. 5, pp. 539-55.MantleSubduction
DS1994-0798
1994
Ransay, R.R.Hwang, P., Taylor, H.R., Rock, N.M.S., Ransay, R.R.Mineralogy, geochemistry and petrogenesis of the Metters bore no. 1lamproite pipe, Calwywyardah field.Mineralogy and Petrology, Vol. 51, No. 2-4, pp. 195-226.Australia, Western AustraliaLamproite, geochemistry, petrology, Deposit - Metters Bore No. 1, West Kimberley
DS1998-1205
1998
Ransom, B.Ransom, B., Kastner, M., Spivack, A.J.Chlorine fluid cycling in subduction zones: evidence chloride concentrations and chlorine stable isotopes.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1233-4.MantleSubduction
DS1920-0295
1926
Ransome, F.L.Ransome, F.L.Review of die Diamantwurste Suedwest AfrikasEconomic Geology, Vol. 21, PP. 734-736.Southwest Africa, NamibiaRegional Geology, Littoral Diamond Placers
DS1900-0212
1903
Ransome, S.Ransome, S.The Engineer in South Africa. a Review of the Industrial Situation in South Africa After the War and a Forecast of the Possibilities of the Country.Westminster: Constable And Co., 391P.Africa, South AfricaMining, Equipment, Kimberley
DS201811-2602
2018
Ranta, E.Ranta, E., Stockmann, G., Wagner, T., Fusswinkel, T., Sturkell, E., Tollefsen, E., Skelton, A.Fluid-rock reactions in the 1.3 Ga siderite carbonatite of the Gronnedal-Ika alkaline complex, southwest Greenland.Contributions to Mineralogy and Petrology, Vol. 173, 26p. Doi.org/10.1007/s00410-018-1505-yEurope, Greenlandcarbonatite

Abstract: Petrogenetic studies of carbonatites are challenging, because carbonatite mineral assemblages and mineral chemistry typically reflect both variable pressure-temperature conditions during crystallization and fluid-rock interaction caused by magmatic-hydrothermal fluids. However, this complexity results in recognizable alteration textures and trace-element signatures in the mineral archive that can be used to reconstruct the magmatic evolution and fluid-rock interaction history of carbonatites. We present new LA-ICP-MS trace-element data for magnetite, calcite, siderite, and ankerite-dolomite-kutnohorite from the iron-rich carbonatites of the 1.3 Ga Grønnedal-Íka alkaline complex, Southwest Greenland. We use these data, in combination with detailed cathodoluminescence imaging, to identify magmatic and secondary geochemical fingerprints preserved in these minerals. The chemical and textural gradients show that a 55 m-thick basaltic dike that crosscuts the carbonatite intrusion has acted as the pathway for hydrothermal fluids enriched in F and CO2, which have caused mobilization of the LREEs, Nb, Ta, Ba, Sr, Mn, and P. These fluids reacted with and altered the composition of the surrounding carbonatites up to a distance of 40 m from the dike contact and caused formation of magnetite through oxidation of siderite. Our results can be used for discrimination between primary magmatic minerals and later alteration-related assemblages in carbonatites in general, which can lead to a better understanding of how these rare rocks are formed. Our data provide evidence that siderite-bearing ferrocarbonatites can form during late stages of calciocarbonatitic magma evolution.
DS1996-1162
1996
RaoRao, NVC, Madhavran, V.Titanium rich phlogopites from the Zangamajupalle kimberlitic rock, AndhraPradesh, India.Journal of Geological Society India, Vol. 47, No. 3, March pp. 355-363.IndiaPetrography, Deposit -Zangamajupalle
DS2003-1138
2003
RaoRay, L., Kumar, P.S., Reddy, G.K., Roy, S., Rao, G.V., Srinivasan, R., RaoHigh mantle heat flow in a Precambrian granite province: evidence from southern IndiaJournal of Geophysical Research, Vol. 108, B2, 10.1029/2001JB000688IndiaUHP
DS2003-1139
2003
RaoRay, L., Kumar, P.S., Reddy, G.K., Roy, S., Rao, G.V., Srinivasan, R., RaoHigh mantle heat flow in a Precambrian granulite province: evidence from southernJournal of Geophysical Research, Vol. 108, 2, ETG 6IndiaUHP, Geothermometry
DS200712-0871
2006
RaoRao, Viljaya, V., Sain, K., Reddy, P.R., Mooney, W.D.Crustal structure and tectonics of the northern part of the southern Granulite Terrane, India.Earth and Planetary Science Letters, Vol. 251, 1-2, Nov. 15, pp.90-103.IndiaTectonics - not specific to diamonds
DS1970-0809
1973
Rao, A.V.K.Rajaraman, S., Rao, A.V.K.Report on the Investigation for Diamond Carries Out in Pipe-1 in Wajrakarur, Anantapur District, Andhra Pradesh.India Geological Survey Program Report, FOR 1968-1973India, Andhra PradeshDiamond Prospecting
DS1986-0321
1986
Rao, A.V.R.Guptasarma, D., Chetty, T.R.K., Murthy, D.S.N*n., Rao, A.V.R.Discovery of a new kimberlite pipe in Andhra Pradesh by streamsedimentsamplingJournal of Geological Society India, Vol. 27, No. 3, March pp. 313-316IndiaGeochemistry
DS1975-0388
1976
Rao, B.B.Rao, B.B.A Note on the Micaceous Kimberlitic Dyke in the Cumbum Formation Near Zangamrajupalle Cuddapah District.Indian Minerals, Vol. 30, No. 1, PP. 55-58.India, Andhra PradeshMineralogy, Petrography
DS1994-1265
1994
Rao, B.B.Natarajan, M., Rao, B.B., Parthasan, R., Kumar, A.2, 0 GA old pyroxenite-carbonatite complex of Hogenakal, Tamil-Nadu, SouthIndia.Precambrian Research, Vol. 65, No. 1-4, January pp. 167-181.IndiaCarbonatite, Geochronology
DS1995-1072
1995
Rao, B.B.Le Bas, M.J., Rao, B.B.Are the Vinjamur rocks carbonatites or meta-limestones?Journal of Geological Society India, Vol. 46, No. 2, August pp. 125-138.IndiaCarbonatite
DS1988-0498
1988
Rao, B.K.N.Nayak, S.S., Viswanathan, C.V.K., Reddy, T.A.K., Rao, B.K.N.New find of kimberlitic rocks in Andhra Pradesh near Maddur,MahaboobnagarDistrictJournal of Geological Society India, Vol. 31, No. 3, March pp. 343-346IndiaBlank
DS1987-0162
1987
Rao, B.V.Dressler, B.O., Morrison, G.G., Peredery, W.V., Rao, B.V.The Sudbury structure, Ontario, Canada- a ReviewBraunschweig Wiesbaden Vieweg, pp. 39-68OntarioSudbury, Impact structure
DS1995-1543
1995
Rao, C.Rao, C., et al.Petrochemistry and significance of the Ramannapeta lamproite, KrishnaValley, Andhra Pradesh.Terra Nova, Abstract Vol., p. 295.IndiaLamproite
DS200412-0684
2004
Rao, C.K.Gokarn, S.G., Gupta, G., Rao, C.K.Geoelectric structure of the Dharwar Craton from magnetotelluric studies: Archean suture identified along the Chitradurga GadagGeophysical Journal International, Vol. 158, 2, pp. 712-728.IndiaGeophysics - magnetotellurics
DS200412-1621
2004
Rao, C.K.Rao, C.K., Ogawa, Y., Gokarn, S.G., Gupta, G.Electromagnetic imaging of magma across the Narmada Son lineament, central India.Earth Planets and Space, Vol. 56, 2, pp. 229-238.. IngentaIndiaGeophysics - magnotellurics
DS201412-0302
2013
Rao, C.K.Gokarn, S.G., Rao, C.K., Selvaraj, C., Gupta, G., Singh, B.P.Crustal evolution and tectonics of the Archean Bundelk hand craton, central India.Journal of the Geological Society of India, Vol. 82, No. 5, pp. 455-460.IndiaTectonics
DS1996-1157
1996
Rao, C.N.V.Rao, C.N.V., Miller, J.A., Pyle, D.M., Madhavan, V.New Proterozoic K-Ar ages for some kimberlites and lamproites from the Cuddapah Basin, Dharwar Craton:Precambrian Research, Vol. 79, pp. 363-369.India, MahbubnagarLamproite, Geochronology, Deposit -Ramannapeta, Kotakonda, Chelima
DS1996-1158
1996
Rao, C.N.V.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
DS200812-0858
2008
Rao, C.R.M.Patel, S.C., Ravi, S., Rao, C.R.M., Rama Rao, G., Nayak, S.S.Mineralogy and geochemistry of Wajrakaruru kimberlites, southen India.9IKC.com, 3p. extended abstractIndiaDeposit - Wajrakarur petrography
DS1989-1442
1989
Rao, C.V.R.Sringesh, D., Rai, S.S., Ramesh, D.S., Gaur, V.K., Rao, C.V.R.Evidence for thick continental roots beneath South Indian shieldGeophysical Research Letters, Vol. 16, No. 9, September pp. 1055-1058IndiaMantle
DS1996-1159
1996
Rao, D. Atchuta.Rao, D. Atchuta.Intra crustal structure inferred from aeromagnetics Eastern Dharwar Craton and its significance kimberliteJournal of Geological Society India, Vol. 48, No. 4, Oct. pp. 391-402.IndiaGeophysics -aeomagnetics, Kimberlite exploration
DS1981-0344
1981
Rao, D.A.Rao, D.A., Sanker narayan, P.V.Structural Control of Emplacement of Kimberlite Pipes at Panna- a Suggestion from Aeromagnetics.Geoexploration., Vol. 19, PP. 207-228.India, Madhya PradeshKimberlite, Geophysics, Airmag
DS1991-1398
1991
Rao, D.BRao, D.B, Babu, N.R.A FORTRAN 77 Computer program for a 3-dimensional analysis of gravity anomalies with variable density contrastJournal of Geophysical Research, Vol. 17, No. 5, pp. 655-668GlobalGravity anomalies
DS200412-1622
2004
Rao, D.G.Rao, D.G., Krishna, K.S., Neprochnov, Yu.P., Grinko, B.N.Satellite gravity anomalies and crustal features of the central Indian Ocean basin.Current Science, Vol. 86, 7, April 10, pp. 948-957.IndiaTectonics, crustal, lineaments
DS200812-0936
2008
Rao, D.V.S.Rao, D.V.S., Balaram, V., Raju, K.N., Sridhar, D.N.Paleoproterozoic boninite like rocks in an intracratonic setting from northern Bastar Craton, central India.Journal of the Geological Society of India, Vol. 27, 3, pp. 373-380.IndiaBoninites
DS2003-1138
2003
Rao, G.V.Ray, L., Kumar, P.S., Reddy, G.K., Roy, S., Rao, G.V., Srinivasan, R., RaoHigh mantle heat flow in a Precambrian granite province: evidence from southern IndiaJournal of Geophysical Research, Vol. 108, B2, 10.1029/2001JB000688IndiaUHP
DS2003-1139
2003
Rao, G.V.Ray, L., Kumar, P.S., Reddy, G.K., Roy, S., Rao, G.V., Srinivasan, R., RaoHigh mantle heat flow in a Precambrian granulite province: evidence from southernJournal of Geophysical Research, Vol. 108, 2, ETG 6IndiaUHP, Geothermometry
DS200412-1637
2003
Rao, G.V.Ray, L., Kumar, P.S., Reddy, G.K., Roy, S., Rao, G.V., Srinivasan, R., Rao, R.U.M.High mantle heat flow in a Precambrian granulite province: evidence from southern India.Journal of Geophysical Research, Vol. 108, 2, ETG 6IndiaUHP Geothermometry
DS1991-0198
1991
Rao, H.V.Burra Subrahmanyam, B., Subba Rao, J.A.V.R.K., Rao, H.V.Three probable locations for kimberlites in Wajrakarur -Lattavaram -P.C.Pyapilli area, Andhra PradeshJournal of Geological Society India, Vol. 37, May pp. 443-451IndiaKimberlite, Geophysics -gravity
DS201603-0416
2016
Rao, I.Rao, I.When culture governs business practice: a look at Indian diamond cutting and polishing industry.Global Business and Organizational Excellence, Vol. 35, 3, pp. 6-17.IndiaCutting and polishing industry

Abstract: As informal firms in emerging markets are expanding their role in global supply chains, managers of formal multinational organizations are increasingly relying on their services. Yet, little is known about the organizational aspects of enterprises in the informal sector. An investigation of informal firms engaged in the cutting and polishing of diamonds (CPD) in Surat, India, the world's hub of diamond manufacturing, reveals that in the absence of well-defined strategies, structures, and processes, the intangible aspect of organizing—specifically, organizational culture—governs business practices. Despite the strong clan-like orientation of these firms and a culture focused on loyalty, trust, team work, and consensus, the study found evidence of hierarchical characteristics and market-driven leadership. Coupled with insightful observations of the overall Indian CPD sector, these findings can help guide managers in planning strategies for effective partnerships with informal firms, regardless of their industry.
DS2002-1302
2002
Rao, I.B.R.Ramadass, G., Rao, I.B.R., Himabindu, D., SrinivasuluPseudo surface velocities (densities) and pseudo depth densities along profiles Dharwar Craton, India.Current Science, Vol.82,No.2, pp. 197-201.IndiaGeophysics - seismics, Craton - Dharwar
DS2003-1126
2003
Rao, I.B.R.Ramadass, G., Rao, I.B.R., Srinivasulu, N., Himabindu, D.Density studies in the Dharwar Craton along the Jadcharla Goa subtransectJournal Geological Society of India, Vol. 61, 4, pp. 439-448.IndiaGeophysics - seismics
DS200412-1615
2003
Rao, I.B.R.Ramadass, G., Rao, I.B.R., Srinivasulu, N., Himabindu, D.Density studies in the Dharwar Craton along the Jadcharla Goa subtransect.Journal Geological Society of India, Vol. 61, 4, pp. 439-448.IndiaGeophysics - seismics
DS200512-0888
2005
Rao, I.B.R.Ramadass, G., Rao, I.B.R., Himabindu, D.Regional appraisal from gravity investigations in the Dharwar Craton: Jadcharla - Goa transect.Journal of the Geological Society of India, Vol. 65, 1, pp. 61-69.IndiaGeophysics - gravity not specific to diamonds
DS1989-0118
1989
Rao, J.M.Bhattacharji, S., Rao, J.M.Mafic dikes and dike swarms around Proterozoic Cuddapah Basin, south India:their mode of emplacement and geodynamic significanceNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 24. AbstractIndiaDykes
DS1990-0974
1990
Rao, J.M.Madhaven, V., Rao, J.M., Sprininasan, T.P., Sprininansan, M.The mid-Proterozoic dyke swarm of mica lamprophyres and microshonkinites from Elchuru IndiaMafic dykes and emplacement mechanisms, Editors A.J. Parker, P.C., pp. 363-372IndiaLamprophyric dykes, Shonkinites
DS1993-1283
1993
Rao, J.M.Rao, J.M., Charan, S.N.Petrography and geochemistry of the pipe 7 kimberlite, Arantapur Andhra Pradesh India.Journal of Geological Society India, Vol. 42, No. 5, November pp. 469-480.IndiaPetrography, Arantapur -Pipe 7
DS1999-0435
1999
Rao, J.M.Madhaven, V., Rao, J.M., Srinivas, M.Mid Proterozoic intraplate alkaline magmatism in the eastern Dharwar Craton of India: the Cuddapah ProvinceJournal of Geological Society IndiaM., Vol. 53, No. 2, Feb. 1, pp. 143-62.India, CuddapahAlkaline rocks, Magmatism, Craton
DS200612-1126
2001
Rao, K.N.Rao, K.R.P., Rao, K.N., Dhakate, M.V., Nayak, S.S.Petrology and mineralogy of mantle xenoliths of Wajrakarur and Narayanpet kimberlite fields, Andhra Pradesh, India.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 577-591.India, Andhra PradeshXenoliths
DS2002-1307
2002
Rao, K.R.Rao, K.R.Elemental osmium: the latest superhard materialCurrent Science, Vol.82,10,May 25, pp. 1198-2001.GlobalOsmium - brief overview
DS2002-1308
2002
Rao, K.R.Rao, K.R.Nuclear reactor at the core of the Earth! - a solution to the riddles of relative abundances of helium isotopes and geomagnetic field variability.Current Research, Vol. 82, No. 2, Jan. 25, pp. 126-7.MantleHelium isotopes
DS1998-1206
1998
Rao, K.R.P.Rao, K.R.P., Reddy, T.A.K., Rao, N.V.Geology, petrology and geochemistry of Narayanpet kimberlites in Andhra Pradesh and Karnataka.Journal of Geological Society India, Vol. 52, No. 6, Dec. pp. 663-76.India, South IndiaKimberlites, Deposit - Narayanpet, Krishna, Bhima Rivers
DS1999-0579
1999
Rao, K.R.P.Rao, K.R.P.Compositional study of spinels from Wajrakarur Pipe 10 (Anumpalle) and its significance in diamond prospectingJournal of Geological Society India, Vol. 53, No. 5, May pp. 617-IndiaMineralogy - spinels, Deposit - Wajrakarur Pipe 10
DS1999-0584
1999
Rao, K.R.P.Ravi, S., Bhaskara Rao, K.S., Rao, K.R.P.Search for kimberlites in the granite greenstone terrain in the central segment of Wajrakarur kimberlite field, Anantapur district.Geological Society of India Records, Vol. 132,5, pp.40-43.India, Andhra PradeshKimberlite
DS1999-0722
1999
Rao, K.R.P.Suresh, G., Dhakate, M.V., Rao, K.R.P.Delineation and assessment of Diamondiferous nature of Chintalampalle ( P -12) and Gollapalle ( CC-5) kimberlites, Anantapur District.Geological Society of India Records, Vol. 132, 5, pp. 45-9.India, Andhra PradeshDiamond - resources
DS2002-1309
2002
Rao, K.R.P.Rao, K.R.P.Comments on: pattern of occurrence of kimberlite pipes based on gravity and magnetic anomalies in Wajrakarur Lattavaram region, Andhra Pradesh by Vasanthi and MallicJournal of the Geological Society of India, Vol. 60, 4, Sept. pp. 350-352.India, Andhra PradeshGeophysics - gravity, magnetics
DS200412-1067
2001
Rao, K.R.P.Kumar, A., Gopalan, K., Rao, K.R.P., Nayak, S.S.Rb Sr ages of kimberlites and lamproites from eastern Dhawar Craton, South India.Journal of the Geological Society of India, Vol. 58, pp. 135-142.IndiaGeochronology
DS200412-1414
2001
Rao, K.R.P.Nayak, S.S., Rao, K.R.P., Kudari, S.A.K., Ravi, S.Geology and tectonic setting of kimberlites and lamproites of southern India.Geological Society of India Special Publication, No.58, pp. 603-613.IndiaTectonics
DS200412-1623
2002
Rao, K.R.P.Rao, K.R.P.Comments on: pattern of occurrence of kimberlite pipes based on gravity and magnetic anomalies in Wajrakarur Lattavaram region,Journal of the Geological Society of India, Vol. 60, 4, Sept. pp. 350-352.India, Andhra PradeshGeophysics - gravity, magnetics
DS200612-0968
2001
Rao, K.R.P.Nayak, S.S., Rao, K.R.P., Kudati, S.A.D., Ravi, S.Geology and tectonic setting of the kimberlites and lamproites of southern India. Wajrakarur, Natayanpet, Dharwar Craton, Chigicherla.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 567-575.India, Andhra PradeshTectonics
DS200612-1125
2001
Rao, K.R.P.Rao, K.R.P., Nayak, S.S., Reddy, T.A.K., Dhakate, M.V., Chowdary, V.S., Ravi, S., Suresh, G., Rao, K.S.B.Geology, petrology, geochemistry and mineral chemistry of new kimberlite fields in the Wajrakarur kimberlite field, Anantapur district, Andhra Pradesh.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 593-602.India, Andhra PradeshGeochemistry
DS200612-1126
2001
Rao, K.R.P.Rao, K.R.P., Rao, K.N., Dhakate, M.V., Nayak, S.S.Petrology and mineralogy of mantle xenoliths of Wajrakarur and Narayanpet kimberlite fields, Andhra Pradesh, India.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 577-591.India, Andhra PradeshXenoliths
DS1992-0237
1992
Rao, K.S.Chatterjee, A.K., Rao, K.S.Majhgawan Diamondiferous pipe (Madhya Pradesh India) a geologicalappraisalInternational Roundtable Conference on Diamond Exploration and Mining, held, pp. 189-208IndiaGeology, Deposit -Majhgawan
DS1995-0293
1995
Rao, K.S.Chatterjee, A.K., Rao, K.S.Majhgawan Diamondiferous pipe, Madhya Pradesh India - a reviewJournal of Geological Society India, Vol. 45, Feb. pp. 175-189.IndiaKimberlite, lamproite, Deposit -Majhgawan
DS1997-0825
1997
Rao, K.S.Mukherjee, A., Rao, K.S., Chatterjee, A.K.Chemistry of phlogopite megacrysts in Majhgaman Diamondiferous pipe, Madhya Pradesh.Journal of Geological Society India, Vol. 49, No. 2, Feb. pp. 203-206.IndiaGeochemistry, Deposit - Majhgaman
DS1998-1054
1998
Rao, K.S.Mukherjee, A., Rao, K.S., Babu, E.V.S.S.K.Cluster analysis and nickel thermometry of garnet xenocrysts from Majhgawan diamondiferous pipe, Panna.Journal of Geological Society India, Vol. 52, No. 3, Sept. pp. 273-278.India, Madhya PradeshGeothermometry, Deposit - Majhgawan
DS1998-1207
1998
Rao, K.S.Rao, K.S., Babu, E.V.S.S.K., Roy, G.Compositional study of spinels from Wajrakarur Pipe 10 (Anumpalle)Ananthapur District diamond prospectivityJournal of Geological Society India, Vol. 52, No. 6, Dec. pp. 677-82.IndiaPetrology - spinels, Deposit - Pipe 10
DS200612-0875
2001
Rao, K.S.Mathew, M.P., Ramachandra, H.M., Gouda, H.C., Singh, R.K., Acharya, G.R., Murthy, C.V.V.S., Rao, K.S.IGRF corrected regional aeromagnetic anomaly map of parts of Peninsular India - potential for mapping and mineral exploration.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 395-405.India, Andhra Pradesh, Karnataka, Tamil Nadu, KeralaGeophysics - magnetics
DS200612-1125
2001
Rao, K.S.B.Rao, K.R.P., Nayak, S.S., Reddy, T.A.K., Dhakate, M.V., Chowdary, V.S., Ravi, S., Suresh, G., Rao, K.S.B.Geology, petrology, geochemistry and mineral chemistry of new kimberlite fields in the Wajrakarur kimberlite field, Anantapur district, Andhra Pradesh.National Seminar on Exploration Survey, Geological Society of India Special Publication, No. 58, pp. 593-602.India, Andhra PradeshGeochemistry
DS201508-0346
2015
Rao, K.V.S.Chalapathi Rao, N.V., Atiullah, Kumar, A., Sahoo, S., Nanda, P., Chahong, N., Lehmann, B., Rao, K.V.S.Petrogenesis of Mesoproterozoic lamproite dykes from the Garledinne (Banganapalle) cluster, south western Cuddapah Basin, southern India.Mineralogy and Petrology, in press available 22p.IndiaLamproite

Abstract: We report mineral chemistry and whole-rock major and trace-element geochemistry for a recent find of Mesoproterozoic (~1.4 Ga) lamproites from the Garledinne (Banganapalle) cluster, south-western part of the Paleo-Mesoproterozoic Cuddapah Basin, southern India. The Garledinne lamproites occur as WNW-ESE-trending dykes that have undergone varying degree of pervasive silicification and carbonate alteration. Nevertheless, their overall texture and relict mineralogy remain intact and provide important insights into the nature of their magmas. The lamproite dykes have porphyritic to weakly porphyritic textures comprising pseudomorphed olivine macrocrysts and microphenocrysts, titanian phlogopite microphenocrysts, spinel having a compositional range from chromite to rarely magnesiochromite, Sr-rich apatite and niobian rutile. The Garledinne and other Cuddapah Basin lamproites (Chelima and Zangamarajupalle) collectively lack sanidine, clinopyroxene, potassic richterite, and titanite and are thus mineralogically distinct from the nearby Mesoproterozoic lamproites (Krishna and Ramadugu) in the Eastern Dharwar Craton, southern India. The strong correlation between various major and trace elements coupled with high abundances of incompatible and compatible trace elements imply that alteration and crustal contamination have had a limited effect on the whole-rock geochemistry (apart from K2O and CaO) of the Garledinne lamproites and that olivine fractionation played an important role in their evolution. The Garledinne lamproites represent small-degree partial melts derived from a refractory (previously melt extracted) peridotitic mantle source that was subsequently metasomatised (enriched) by carbonate-rich fluids/melts within the garnet stability field. The involvement of multiple reservoirs (sub-continental lithospheric mantle and asthenosphere) has been inferred in their genesis. The emplacement of the Garledinne lamproites is linked to extensional events, across the various Indian cratons, related to the break-up of the Proterozoic supercontinent of Columbia.
DS1970-0811
1973
Rao, M.G.Rao, M.G.Alkalic Lamprophyres from Garo Hills, AssamIndia Geological Survey Records, Vol. 105, PT. 2, PP. 121-124.India, AssamMineralogy
DS1975-0601
1977
Rao, M.G.Rao, M.G., Misra, R.C.Investigation for Diamonds in Wajrakarur and Lattivaram Areas, Anantapur District, A.p.Geological Survey INDIA PROGR. Report, FOR 1974-1977India, Andhra PradeshDiamond Prospecting
DS200412-1841
2004
Rao, M.R.K.Singh, A.P., Mishra, D.C., Gupta, S.B., Rao, M.R.K.Crustal structure and domain tectonics of the Dharwar Craton ( India): insights from new gravity data.Journal of Asian Earth Sciences, Vol. 23, 1, March pp. 141-152.IndiaTectonics, geophysics - gravity, continental collision
DS200412-1624
2004
Rao, M.S.Rao, M.S., Fareeduddin, Godhavari, K.S., Chander, S., Sisodia, C.P.Carbonaceous metaexhalite of shungitic affinity in Paleoproterozoic Aravelli Supergroup, Dugocha area, Rajasthan.Journal Geological Society of India, Vol. 63, 5, pp. 522-532IndiaCarbon, graphite
DS2002-1310
2002
Rao, M.V.S.Rao, M.V.S., Narayana, B.L.Geochemistry and petrogenesis of Kunduru Betta calc alkaline ring complex in the Dharwar Craton.Gondwana Research, Vol. 5,2,pp. 453-66.India, southernAlkaline rocks
DS1996-1160
1996
Rao, N.V.Rao, N.V., Chalapthi, Madhaven, V.A new look at the olivine lamproitic rocks of the Maddur Narayanpet area, Mahbubnagar District, A.P.Journal of Geological Society India, Vol. 47, No. 6, June pp. 549-664.IndiaLamproites, Deposit -Maddur Narayanpet
DS1998-1206
1998
Rao, N.V.Rao, K.R.P., Reddy, T.A.K., Rao, N.V.Geology, petrology and geochemistry of Narayanpet kimberlites in Andhra Pradesh and Karnataka.Journal of Geological Society India, Vol. 52, No. 6, Dec. pp. 663-76.India, South IndiaKimberlites, Deposit - Narayanpet, Krishna, Bhima Rivers
DS1996-1161
1996
Rao, N.V.C.Rao, N.V.C., Madhavan, V.Some observations on the geochemistry of Ramannapeta -Ustapalle lamproiticbody, Krishna District AP.Journal of Geological Society India, Vol. 47, No. 4, Apr. 1, pp. 409-418.IndiaLamproite, Deposit -Ramannapeta-Ustapalle
DS1999-0580
1999
Rao, N.V.C.Rao, N.V.C., Miller, J.A., Madhavan, V.Precise 40 Ar-39 Ar age determinations of the Kotonda kimberlite and Chelima lamproite : implications timingJournal of Geological Society India, Vol. 53, No. 4, Apr. pp. 425-32.IndiaGeochronology - mafic dyke swarm emplacement, Argon, Craton - Dharwar
DS200612-1127
2006
Rao, N.V.C.Rao, N.V.C.Mesoproterozoic Diamondiferous ultramafic pipes at Majkgawan and Hinota, Panna area, central India: key to the nature of sub-continental lithospheric mantle...Journal of Earth System Science, Vol. 115, 1m pp. 161-183.Asia, IndiaVindhyan Basin
DS200812-0937
2008
Rao, N.V.C.Rao, N.V.C.Precambrian alkaline potassic ultrapotassic mafic ultramafic magmatism in Peninsular India.Journal of the Geological Society of India, Vol. 72, 1, pp. 57-74.IndiaAlkalic
DS201912-2797
2019
Rao, N.V.ChalapthiKumar, R.K., Praveer, P., Rao, N.V.Chalapthi, Chakrabarti, R., Pandit, D.Petrogenesis of an alkaline lamprophyre ( camptonite) with ocean island basalt ( OIB)-affinity at the NW margin of the Cuddapah Basin, eastern Dharwar craton, southern India.Neues Jahbuch fur Mineralogy, Vol. 196, p2, pp. 149-177.Indiacamptonite

Abstract: We report petrology and geochemistry (including Sr and Nd isotopes) of a fresh lamprophyre at Ankiraopalli area at the north-western margin of Paleo-Mesoproterozoic Cuddapah basin, eastern Dharwar craton, southern India. Ankiraopalli samples possess a typical lamprophyre porphyritic-panidiomorphic texture with phenocrysts of kaersutite and diopside set in a plagioclase dominant groundmass. Combined mineralogy and geochemistry classify it as alkaline lampro- phyre in general and camptonite in particular. Contrary to the calc-alkaline and/or shoshonitic orogenic nature portrayed by lamprophyres occurring towards the western margin of the Cuddapah basin, the Ankiraopalli samples display trace element composition revealing striking similarity with those of ocean island basalts, Italian alkaline lamprophyres and highlights an anorogenic character. However, the87 Sr/86 Srinitial (0.710316 to 0.720016) and eNdinitial (- 9.54 to - 9.61) of the Ankiraopalli lamprophyre show derivation from an 'enriched' mantle source showing long term enrichment of incompatible trace elements and contrast from those of (i) OIB, and (ii) nearby Mahbubnagar alkaline mafic dykes of OIB affinity. Combining results of this study and recent advances made, multiple mantle domains are identified in the Eastern Dharwar craton which generated distinct Mesoproterozoic lamprophyre varieties. These include (i) Domain I, involving sub-continental lithospheric mantle source essentially metasomatized by subduction-derived melts/fluids (represented by orogenic calcalkaline and/or shoshonitic lamprophyres at the Mudigubba, the Udiripikonda and the Kadiri); (ii) Domain II, comprising a mixed sub-continental lithospheric and asthenospheric source (represented by orogenic-anorogenic, alkaline to calc-alkaline transitional lamprophyres at the Korakkodu), and (iii) Domain III, representing a sub-continental lithospheric source with a dominant overprint of an asthenospheric (plume) component (represented by essentially alkaline lamprophyres at the Ankiraopalli). Our study highlights the varied mantle source heterogeneities and complexity of geodynamic processes involved in the Neoarchean-Paleo/Mesoproterozoic evolution of the Eastern Dharwar craton.
DS1995-1544
1995
Rao, N.Y.C.Rao, N.Y.C.A new occurrence of kimberlite near Kotakonda Mahboobnagar District, AndhraPradesh. #2Journal of Geological Society India, Vol. 45, No. 5, May pp. 605-606.IndiaKimberlite
DS1950-0234
1955
Rao, P.Rao, P.Preliminary Investigation of Old Diamond Workings in Hyderabad State.India Geological Survey, UNPUB. ReportIndiaProspecting
DS1960-0184
1961
Rao, P.S.Rao, P.S.The Geology and Mineral Deposits of the Southern and Western Extension of Gani Copper Belt, Kurnool District.Geological Survey INDIA UNPUBL. REPORT, FOR 1959-1960., India, Andhra PradeshProspecting
DS1960-0387
1963
Rao, P.S.Rao, P.S., Phadtre, P.N.Investigation for Diamond in Wajrakarur, Anantapur DistrictIndia Geological Survey, UNPUBL. ReportIndiaProspecting
DS1960-0388
1963
Rao, P.S.Rao, P.S., Phadtre, P.N.Investigation for Diamonds in Wajrakarur Area Anatapur District, A.p.India Geological Survey Program Report, FOR 1961-1963, PP.India, Andhra PradeshProspecting
DS1960-0489
1964
Rao, P.S.Rao, P.S., Konala, R.K.R.Prospecting for Lead, Zinc and Diamond in Cuddapah and Kurnool Districts.India Geological Survey, UNPUBL. ReportIndia, Madhya PradeshProspecting
DS1960-0732
1966
Rao, P.S.Rao, P.S., Phadtre, P.N.Kimberlite Pipe Rocks of Wajrakarur, Anantapur DistrictGeological Society INDIA Journal, Vol. 7, PP. 118-123.India, Andhra PradeshGeology
DS1975-0906
1979
Rao, P.S.Akella, J., Rao, P.S., Mcallister, R.H., Boyd, F.R., Meyer, H.O.Mineralogical Studies on the Diamondiferous Kimberlite of The Wajrakarur Area, Southern India #2Proceedings of Second International Kimberlite Conference, Vol. 1, PP. 172-177.India, Andhra PradeshMineralogy
DS1930-0118
1932
Rao, R.M.B.Pichamuthu, C.S., Rao, R.M.B.A Note on the Tuff of WajrakarurIndian Sci. Congr. 19th. Session Proceedings, ABSTRACT.India, Andhra PradeshPetrography
DS1986-0140
1986
Rao, R.S.Chetty, T.R.K., Rao, R.S.Proto Penner river course and its role in the distribution of alluvial diamonds- as evidence from Land sat dataJournal of Geological Society India, Vol. 28, No. 6, December, pp. 48-IndiaRemote Sensing, Placers
DS2003-1192
2003
Rao, R.U.Roy, S., Rao, R.U.Towards a crustal thermal model for the Archean Dharwar craton, southern IndiaPhysics and Chemistry of the Earth, parts A,B,C, Vol. 28, 9-11, pp. 361-73.IndiaBlank
DS200412-1696
2003
Rao, R.U.Roy, S., Rao, R.U.Towards a crustal thermal model for the Archean Dharwar craton, southern India.Physics and Chemistry of the Earth Parts A,B,C, Vol. 28, 9-11, pp. 361-73.IndiaGeothermometry
DS2000-0838
2000
Rao, R.U.M.Roy, S., Rao, R.U.M.Heat flow in the Indian ShieldJournal of Geophysical Research, Vol.105, No.11, Nov.10, pp.25587-604.IndiaGeothermometry, Heat flow
DS200412-1637
2003
Rao, R.U.M.Ray, L., Kumar, P.S., Reddy, G.K., Roy, S., Rao, G.V., Srinivasan, R., Rao, R.U.M.High mantle heat flow in a Precambrian granulite province: evidence from southern India.Journal of Geophysical Research, Vol. 108, 2, ETG 6IndiaUHP Geothermometry
DS1996-1163
1996
Rao, S.D.V.Rao, S.D.V.Resolving Bouguer anomalies in continents: a new approachGeophysical Research. Letters, Vol. 23, No. 24, Dec. 1, pp. 3543-46.MantleGeophysics - seismics
DS1992-1252
1992
Rao, S.R.Rao, S.R., et al.Waste processing and recycling in mining and metallurgical industries.Proceedings Volume from meetingCanadian Institute of Mining and Metallurgy (CIMM) Society, 366p. no price givenGlobalBook review, Metallurgy and recycling
DS1996-0554
1996
Rao, S.V.Gowd, T.N., Srirama, Rao, S.V., Chary, K.B.Stress field and seismicity in the Indian shield: effects of the collision between India and Eurasia.Pure and Applied Geophysics, Vol. 146, No. 3-4, May 1, pp. 503-532.India, EurasiaTectonics, Geophysics -seismics
DS200912-0649
2007
Rao, T.Roy, P.,Balaram, V., Kumar, A., Sathyanarayan, M., Gnaneshwara, Rao, T.New REE and trace element dat a on two kimberlite reference materials by ICP-MS.Geostandards and Geoanalytical Research, Vol. 31, pp. 261-273.IndiaGeochronology
DS1960-0050
1960
Rao, T.C.Gokhale, K.V.G.K., Rao, T.C.Ore Deposits of India: Diamond DepositsDelhi: Thomson Press, PP. 117-122; PP. 214-215.IndiaGeology, Diamond Occurrences
DS1990-1215
1990
Rao, T.C.Rao, T.C., Vanangamudi, M., Barnwal, J.P.Industrial application of heavy medium cyclone modelAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Meeting, Salt Lake City, February 26, Preprint?GlobalHeavy medium Application, Mineral processing -gener
DS200512-0681
2005
Rao, T.G.Manikyamba, C., Naqvi, S.M., Subba Rao, D.V., Ram Mohan, M., Khanna, T.C., Rao, T.G., Reddy, G.L.Boninites from the Neoarchean Gadwal greenstone belt, eastern Dharwar Craton, India, implications for Archean subduction processes.Earth and Planetary Science Letters, Vol. 230, 1-2, pp. 65-83.IndiaBoninites
DS200612-0858
2005
Rao, T.G.Manikyamba, C., Khanna, T.C., Subba Rao, D.V., Charan, S.N., Rao, T.G.Geochemistry and petrogenesis of Gadwai kimberlites, eastern Dharwar Craton India.Geological Society of India, Bangalore November Meeting Group Discussion on Kimberlites and Related Rocks India, Abstract p. 67-68.India, Andhra Pradesh, Dharwar CratonKimberlite - Gadwai
DS1994-1439
1994
Rao, T.K.Rao, T.K., Sarma, K.J.A new occurrence of kimberlite near Kotakonda, Mahboobhagar district, Andhra Pradesh.Journal Geological Society of India, Vol. 43, No. 1, January pp. 78-85.IndiaKimberlite
DS1995-1545
1995
Rao, T.K.Rao, T.K.A new occurrence of kimberlite near Kotakonda Mahboobnagar District, AndhraPradesh... reply #3Journal of Geological Society India, Vol. 45, No. 5, May pp. 606-607.IndiaKimberlite
DS200612-0970
2005
Rao, T.K.Nayak, S.S., Ravi, S., Sridhar, M., Reddy, N.S., Chowdary, V.S., Bhaskara Rao, K.S., Sinha, K.K., Rao, T.K.Geology and tectonic setting of kimberlites of Dharwar Craton.Geological Society of India, Bangalore November Meeting Group Discussion on Kimberlites and Related Rocks India, Abstract p. 36-38.India, Andhra Pradesh, Dharwar CratonTectonics
DS200612-1046
2006
Rao, T.K.Patel, S.C., Ravi, S., Thakur, S.S., Rao, T.K., Subbarao, K.V.Eclogite xenoliths from Wajrakarur kimberlites, southern India.Mineralogy and Petrology., Vol. 88, 1-2, pp. 363-380.IndiaDeposit - Wajrakarur petrology
DS200612-1047
2006
Rao, T.K.Patel, S.C., Ravi,S., Thakur, S.S., Rao, T.K., Subbarao, K.V.Eclogite xenoliths from Wajrakarur kimberlites, southern India.Mineralogy and Petrology, Vol. 88, 1-2, pp. 363-380.IndiaDeposit - Wajrakarur
DS2000-0775
2000
Rao, V.K.Prakasa, R.G.S., Tewari, H.C., Rao, V.K.Velocity structure in parts of the Gondwana Godavari GrabenJournal of Geological Society India, Vol. 56, No. 4, Oct. 1, pp. 373-84.IndiaTectonics, Graben - not specific to diamonds
DS201706-1087
2017
Rao, V.K.Kumar, R., Bansal, A.R., Anand, P., Rao, V.K., Singh, U.Mapping of magnetic basement in the central India from aeromagnetic dat a for scaling geology.Geophysical Prospecting, in press availableIndiageophysics - aermagnetics

Abstract: The Central Indian region is having complex geology covering the Godavari Graben, the Bastar Craton (including the Chhattisgarh Basin), the Eastern Ghat Mobile Belt, the Mahanadi Graban and some part of the Deccan Trap, the Northern Singhbhum Orogen and the Eastern Dharwar Craton. The region is well covered by reconnaissance scale aeromagnetic data, analyzed for the estimation of basement and shallow anomalous magnetic sources depth using scaling spectral method. The shallow magnetic anomalies are found to vary from 1 to 3 km whereas magnetic basement depth values are found to vary from 2 to 7 km. The shallowest basement depth of 2 km corresponds to the Kanker granites, a part of the Bastar Craton, whereas deepest basement depth of 7 km is for the Godavari Basin and the southeastern part of the Eastern Ghat Mobile Belts near the Parvatipuram Bobbili fault. The estimated basement depth values correlate well with the values found from earlier geophysical studies. The earlier geophysical studies are limited to few tectonic units whereas our estimation provides detailed magnetic basement mapping in the region. The magnetic basement and shallow depth values in the region indicate complex tectonic, heterogeneity and intrusive bodies at different depth which can be attributed to different thermo-tectonic processes since Precambrian.
DS201801-0033
2018
Rao, V.K.Kumar, R., Bansal, A.R., Anand, S.P., Rao, V.K., Singh, U.K.Mapping of magnetic basement in central India from aeromagnetic dat a for scaling geology. Bastar Craton including Chhattisgarth basin.Geophysical Prospecting, Vol. 66, 1, pp. 226-239.Indiageophysics - magnetics

Abstract: The Central Indian region has a complex geology covering the Godavari Graben, the Bastar Craton (including the Chhattisgarh Basin), the Eastern Ghat Mobile Belt, the Mahanadi Graben and some part of the Deccan Trap, the northern Singhbhum Orogen and the eastern Dharwar Craton. The region is well covered by reconnaissance-scale aeromagnetic data, analysed for the estimation of basement and shallow anomalous magnetic sources depth using scaling spectral method. The shallow magnetic anomalies are found to vary from 1 to 3 km, whereas magnetic basement depth values are found to vary from 2 to 7 km. The shallowest basement depth of 2 km corresponds to the Kanker granites, a part of the Bastar Craton, whereas the deepest basement depth of 7 km is for the Godavari Basin and the southeastern part of the Eastern Ghat Mobile Belt near the Parvatipuram Bobbili fault. The estimated basement depth values correlate well with the values found from earlier geophysical studies. The earlier geophysical studies are limited to few tectonic units, whereas our estimation provides detailed magnetic basement mapping in the region. The magnetic basement and shallow depth values in the region indicate complex tectonic, heterogeneity, and intrusive bodies at different depths, which can be attributed to different thermo-tectonic processes since Precambrian.
DS1998-1208
1998
Rao, V.V.Rao, V.V., Gupta, H.K., Tewari, H.C.A geotransect in the Central Indian Shield, across the Narmada Sonlineament and the Central Indian Suture.International Geology Review, Vol. 40, No. 11, Nov. pp. 1021-IndiaTectonics
DS2003-1371
2003
Rao, V.V.Tewari, H.C., Rao, V.V.Structure and tectonics of the Proterozoic Aravalli Delhi geological province, NWMemoirs Geological Society of India, Vol. 53, pp. 57-78. Ingenta 1035483296IndiaBlank
DS200412-1981
2003
Rao, V.V.Tewari, H.C., Rao, V.V.Structure and tectonics of the Proterozoic Aravalli Delhi geological province, NW Indian Peninsular Shield.Memoirs Geological Society of India, Vol. 53, pp. 57-78. Ingenta 1035483296IndiaTectonics
DS200712-0870
2007
Rao, V.V.Rao, V.V., Sain, K., Prasad, B.R.Dipping Moho in the southern part of Eastern Dharwar Craton, India as revealed by the coincident seismic reflection and refraction study.Current Science, Vol. 93, 3, Aug. 10, pp. 330-336.IndiaGeophysics - seismics
DS200812-0938
2008
Rao, V.V.Rao, V.V., Tewari, H.C.Deep crustal seismic studies over the Indian Shield.Glimpses of Geoscience Research in India, The Indian report to IUGS 2004-08, pp. 137-143.IndiaGeophysics - seismics
DS1999-0258
1999
Rao, Y.J.B.Gopalan, K., Kumar, A., Rao, Y.J.B.Precise 40 Ar-39 Ar age determination of the Kotakonda kimberlite and Chelima lamproite: timing of mafic dykesJournal of Geological Society India, Vol. 54, No. 2, pp. 203-4.IndiaCraton - Dhwar, Geochronology, Argon, Dike swarms - emplacement
DS1985-0555
1985
Rao, Y.V.S.Rao, Y.V.S., Murthy, I.V.R.Paleomagnetism and Ages of Dolerite Dikes in Karimnagar District, Andhra Pradesh, India.Geophys. Journal of Roy. Astron. Soc., Vol. 82, No. 2, PP. 331-India, Andhra PradeshBlank
DS1996-0289
1996
Rapalini, A.E.Conti, C.M., Rapalini, A.E., Coria, B., Koukharsky, M.Paleomagnetic evidence of an early Paleozoic rotated terrane in northwestArgentina: a clue for Gondwana.Geology, Vol. 24, No. 10, Oct. pp. 953-956ArgentinaGondwana-Laurentia, Paleomagnetics
DS1998-1209
1998
Rapalini, A.E.Rapalini, A.E.Syntectonic magnetization of the mid-Paleozoic Sierra Grande formation:further constraints on the tectonicsJournal of the Geological Society of London, Vol. 155, No. 1, Jan. pp. 105-114GlobalTectonics
DS200612-1128
2006
Rapalini, A.E.Rapalini, A.E.New late Proterozoic paleomagnetic pole for the Rio de la Plat a craton: implications for Gondwana.Precambrian Research, Vol. 147, 3-4, July 5, pp. 223-233.South America, BrazilGeochronology
DS1987-0602
1987
Rapaport, M.Rapaport, M.Why diamond dealers hate his price list- but can't live without itJewellers Circular Keystone, Vol. CLVIII, No. 12, December pp. 123-125, 128-129GlobalEconomics
DS1991-1399
1991
Rapaport, M.Rapaport, M.The impact of the global economy on diamond pricesInternational Gemological Symposium, June 20-24, 1991 Los Angeles, Gems and Gemology, Vol. 27, Spring, Program p. 9GlobalDiamond prices, Economics
DS2002-1311
2002
Rapaport, M.Rapaport, M.Diamond pricingProspectors and Developers Association of Canada (PDAC) 2002, 1p. abstractGlobalDiamond - pricing
DS201412-0723
2014
Rapaport, M.Rapaport, M.Honest grading: the truth, the whole truth and nothing but the truth.Rapaport , November 9p. AvailableGlobalDiamond industry - ethical
DS201412-0722
2014
Rapaport MagazineRapaport MagazineLucky find in Yakutia. Alrosa opens its biggest underground mine. Udachny.Rapaport , August 8, 5p.Russia, YakutiaDeposit - Udachnaya
DS201604-0590
2015
Rapatsky, V.L.Alexakhin, V.Yu., Bystritsky, V.M., Zamyatin, N.I., Zubarev, E.V., Krasnoperov, A.V., Rapatsky, V.L., Rogov, Yu.N., Sadovsky, A.B., Salamatin, A.V., Salmin, R.A., Sapozhnikov, M.G., Slepnev, V.M., Khabarov, S.V., Razinkov,E.A., Tarasov, O.G., Nikitin,G.M.Detection of diamonds in kimberlite by the tagged neutron method.Nuclear Instruments and Methods in Physics Research Section A., A785, pp. 9-13.TechnologyMethodology

Abstract: A new technology for diamond detection in kimberlite based on the tagged neutron method is proposed. The results of experimental researches on irradiation of kimberlite samples with 14.1-MeV tagged neutrons are discussed. The source of the tagged neutron flux is a portable neutron generator with a built-in 64-pixel silicon alpha-detector with double-sided stripped readout. Characteristic gamma rays resulting from inelastic neutron scattering on nuclei of elements included in the composition of kimberlite are registered by six gamma-detectors based on BGO crystals. The criterion for diamond presence in kimberlite is an increased carbon concentration within a certain volume of the kimberlite sample.
DS1992-0669
1992
Rapela, C.W.Harmon, R.S., Rapela, C.W.Andean magmatism and its tectonic settingGeological Society of America (GSA) Special Paper, No. 265, 350pAndes, Chile, ArgentinaMagmatism, Tectonics
DS1998-1117
1998
Rapela, C.W.Pankhurst, R.J., Rapela, C.W.The proto-Andean margin of GondwanaGeological Society of London Spec. Pub, No. 142, 336p. $ 125.00ArgentinaBook - ad, Basins - subduction
DS1998-1118
1998
Rapela, C.W.Pankhurst, R.J., Rapela, C.W.The Proto Andean margin of Gondwana: an introductionPankhurst Geological Society of London, Special Paper No. 142, pp. 1-9.ArgentinaOrogeny - Sierras Pampeanas, Gondwana - not specific to diamonds
DS1998-1210
1998
Rapela, C.W.Rapela, C.W., Pankhurst, R.J., et al.Early evolution of the Proto-Andean margin of South AmericaGeology, Vol. 26, No. 8, Aug. pp. 707-710Argentina, South America, AndesTectonics, magmatism, Gondwana, Pampean Orogeny
DS200612-1025
2006
Rapela, C.W.Pankhurst, R.J., Rapela, C.W., Fanning, C.M., Marquez, M.Gondwanide continental collision and origin of Patagonia.Earth Science Reviews, Vol. 76, 3-4, June pp. 235-257.South AmericaTectonics
DS200712-0872
2007
Rapela, C.W.Rapela, C.W., Pankhurst, R.J., Casquet, C., Fanning, C.M., Baldor Casado, E.G., Galindo, C., DahlquistThe Rio de la Plat a craton and the assembly of SW Gondwana.Earth Science Reviews, In press availableSouth America, BrazilTectonics
DS200712-0873
2007
Rapela, C.W.Rapela, C.W., Pankhurts, R.J., Casquet, C., Fanning, C.M., Baldo, E.G., Gonzalez-Casado, J.M., Galindo, C., Dahlquist, J.The Rio de la Plate craton and the assembly of SW Gondwana.Earth Science Reviews, Vol. 83, 1-2, pp. 49-82.South America, BrazilCraton, tectonics
DS1992-1253
1992
Raper, J.F.Raper, J.F., Maquire, D.J.Design models and functionality in GISComputers and Geosciences, Vol. 18, No. 4, pp. 387-394GlobalComputer, Program -Geographic information systems -design models
DS1990-1262
1990
Raphanaud, J.Roullet, G., Raphanaud, J., Legendre, J.J.A user friendly microcomputer program for modeling convex polyhedraComputers and Geosciences, Vol. 16, No. 4, pp. 461-516GlobalComputer, Program -model polyhedra
DS201212-0063
2012
Rapinesi, I.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
Rapinesi, I.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
DS1993-0446
1993
Rapolla, A.Florio, G., Fedi, M., Rapolla, A., Fountain, D.M., Shive, P.N.Anisotropic magnetic susceptibility in the continental lower crust and its implications for the shape of magnetic anomalies.Geophysical Research Letters, Vol. 20, No. 23, December 14, pp. 2623-2626.MantleGeophysics Magnetics
DS201708-1742
2017
Rapopo, M.Rapopo, M.The Liqhobong kimberlite cluster: a perspective on the distinct geology, emplacement, dilution and diamond grades for each intrusion.11th. International Kimberlite Conference, PosterAfrica, Lesothodeposit - Liqhobong
DS201708-1743
2017
Rapopo, M.Rapopo, M.The geology of the Liqhobong main pipe kimberlite.11th. International Kimberlite Conference, PosterAfrica, Lesothodeposit - Liqhobong
DS201808-1782
2018
Rapopo, M.Rapopo, M., Sobie, P.The Liqhobong kimberlite cluster: an update on the geology.Mineralogy and Petrology, doi.org/10.1007/s00710-018-0624-5 12p.Africa, Lesothodeposit - Liqhobong

Abstract: The Cretaceous Liqhobong kimberlite cluster comprises at least six known diamondiferous Group 1 kimberlite bodies; namely the circular Main Pipe (8.5 ha), ovoid Satellite Pipe (1.6 ha), Discovery Blow (0.15 ha), Blow (0.1 ha), the Main Dike adjoining the blows and pipes, and one other recently exposed dike. The kimberlites intrude Jurassic Drakensberg lavas and outcrop at ~2650 masl in rugged Maluti Mountain terrain, and are emplaced along a strike of about 2.5km. The cluster represents at least three episodes of structurally controlled kimberlite intrusion; the first which comprised the dike(s?) and the two blows (the blows being dike enlargements emplaced 1km apart) and later the two separate emplacements of the Main and Satellite Pipes.
DS201904-0770
2019
Raposo, D.B.Raposo, D.B., Pereira, S.Y.Hydrochemistry and isotopic studies of carbonatite groundwater systems: the alkaline-carbonatite complex of Barreiro, southeastern Brazil.Environmental Earth Sciences, Vol. 78, pp. 233-South America, Brazilcarbonatite

Abstract: In Brazil, alkaline intrusions are source rocks for several commodities (bauxite, phosphate, niobium and barite, to mention a few), including mineral water. The present study aims to understand by means of chemical and stable isotope analyses, the residence time, circulation and hydrochemical facies of the groundwater systems from the alkaline-carbonatitic complex of Barreiro (State of Minas Gerais, Brazil). This Mesozoic alkaline complex is located in the Brazilian tropical region characterized by weathered soils and fractured rocks, which play an important role in the groundwater dynamics. To assess this influence, groundwater samples from 12 points and water samples from 3 artificial lakes were collected for the determination of chemical element and natural isotope (18O, deuterium and 13C) concentrations and 14C and tritium dating. Two main groundwater categories were revealed: (a) a local, acidic and sub-modern groundwater system developed in thick, poorly mineralized weathered soil from the inner part of ACCB, and (b) a basic, hypothermal, ca. 40-ky-old fractured aquifer developed in mineralized fenitized quartzites. The younger and shallower groundwater circulation is controlled by the present intrusion relief and is prone to environmental impacts. The older, hypothermal groundwater system indicates existing geothermal residual heat provided by the Mesozoic alkaline intrusion.
DS200412-0396
2004
Raposo, M.I.D'Agreela Filho, M.S., Pacca, II., Trinidade, R.I., Teixeira, W., Raposo, M.I., Onstott, T.C.Paleomagnetism and 40 Ar 39 Ar ages of mafic dikes from Salvador ( Brazil): new constraints on the Sao Francisco craton APW pathPrecambrian Research, Vol. 132, 1-2, pp. 55-77.South America, BrazilGeochronology
DS200412-1625
2004
Raposo, M.I.Raposo, M.I., Chaves, A.O., Lojkasek Lima, P., D'Agrella Filho, M.S., Teixeira, W.Magnetic fabrics and rock magnetism of Proterozoic dike swarm from the southern Sao Francisco Craton, Minas Gerais, Brazil.Tectonophysics, Vol. 378, 1-2, pp. 43-63.South America, Brazil, Minas GeraisGeophysics - magnetics
DS200712-0874
2007
Raposo, M.I.Raposo, M.I., D'Agrella Filho, M.S., Pinese, J.P.Magnetic fabrics and rock magnetism of Archean and Proterozoic dike swarms in the Sao Francisco craton, Brazil.Tectonophysics, Vol. 443, 1-2, pp. 53-71.South America, BrazilDike Swarms
DS1995-1546
1995
Raposo, M.I.B.Raposo, M.I.B., Ernesto, M.An early Cretaceous paleomagnetic pole from Ponta Grossa dikes-implications Mesozoic Polar wander pathJournal of Geophysical Research, Vol. 100, No. NB10, Oct, pp. 95-109BrazilGeophysics -paleomagnetics
DS200512-1063
2005
RappSueda, Y., Irifune, T., Nishiyama, N., Rapp, Ferroir, Onozawa, Yagi, Merkel, Miyajima, FunakoshiA new high pressure form of K Al Si3 08 under lower mantle conditions.Geophysical Research Letters, Vol. 31, 23, Dec. 16, DOI 10.1029/2004 GLO21156MantleUHP
DS1990-1237
1990
Rapp, G.R. Jr.Roberts, W.L., Campbell, T.J., Rapp, G.R. Jr.Encyclopedia of minerals ( second edition)Van Nostrand, 979p. approx. $ 140.00GlobalMineralogy, Book review
DS201605-0886
2016
Rapp, R.Rapp, R.Sediment derived fluid metasomatism in the subcratonic lithospheric mantle and the origin of diamonds.DCO Edmonton Diamond Workshop, June 8-10MantleDiamond genesis
DS1990-1216
1990
Rapp, R.P.Rapp, R.P.Vapor-absent partial melting of amphibolite/eclogite at 8-32 Kbar; implications for the origin and growth of the continental crustPh.D. Thesis, Rensselaer Polytechnic Institute, Troy NY, 327pGlobalEclogite, Crust
DS1995-1547
1995
Rapp, R.P.Rapp, R.P.Is eclogite in the sub-continental lithosphere the residue from melting of subducted crust? Experimental..Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 457-459.Russia, SiberiaEclogites, Deposit -Udachnaya
DS1995-1548
1995
Rapp, R.P.Rapp, R.P., Watson, K.B.Dehydration melting of metabasalt at 8-32kbar: implic- ations for continental growth and crust-mantle recycleJournal of Petrology, Vol. 96, No. 4, pp. 891-931MantleMelt, Recycling, Mantle-crust
DS1998-1211
1998
Rapp, R.P.Rapp, R.P., Shimizu, N.The nature of subduction derived metasomatism in the upper mantle:dehydration melting of hydrous basalt.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1237-8.MantleSubduction, Lawsonite, phengite
DS1999-0581
1999
Rapp, R.P.Rapp, R.P., Shimizu, N., Applegate, G.S.Reaction between slab derived melts and peridotite in the mantle wedge:experimental constraints at 3.8 GPaChemical Geology, Vol. 160, No. 4, Sept. 2, pp. 335-56.MantlePeridotite - melting, Slab
DS2000-1002
2000
Rapp, R.P.Wang, W., Gasparik, T., Rapp, R.P.Partitioning of rare earth elements between CaSiO3 perovskite and co-existing phases: inclusions diamondsEarth and Planetary Science Letters, Vol.181, No.3, Sept.15, pp.291-300.GlobalDiamond - inclusions, genesis, Subduction
DS2003-1129
2003
Rapp, R.P.Rapp, R.P., Shimizu, N.On the origin of eclogite and websterite parageneses in the cratonic mantle, and their8 Ikc Www.venuewest.com/8ikc/program.htm, Session 2, AbstractMantleEclogites, diamonds, Craton, magmatism
DS2003-1130
2003
Rapp, R.P.Rapp, R.P., Shimizu, N., Norman, M.D.Growth of early continental crust by partial melting of eclogiteNature, No. 6958, Oct. 9, pp. 605-8.MantleEclogite - subduction
DS2003-1510
2003
Rapp, R.P.Xu, J.F., Shinjo, R., Defant, M.J., Wang, Q., Rapp, R.P.Origin of Mesozoic adakitic intrusive rocks in the Nigzhen area of east China: partialGeology, Vol. 30, 12, Dec.pp. 111-1114.ChinaMelting, mantle, slab
DS200412-1626
2004
Rapp, R.P.Rapp, R.P., Irifune, T., Shimizu, N.Recycling of continental se