| | Journal (article/letter/editorial) | Economic Geology Vol. 71, 1976, pp. 157--176 Detrital Gold, Uranium,and Pyrite Concentrations Belated to Sedimentology...E. L. MâąNTER Abstract The Vaal Reef placer was depositedduring the Vaal Stage of the Upper Witwatersrand...that describes the genesisof the Vaal Reef placer. Resultsshowthat the Vaal Reef placerwas a shorelinefeatureof...entry point. The sedimentsin the footwall of the Vaal Reef placer regressedinto the depositorydown a southeastern...southeastern paleoslope.Protracteddeposition of the Vaal Reefplacer,marked by a maturepebblyquartz-arenite | | | Journal (article/letter/editorial) | Abstract Mineralized conglomerates in the Witwatersrand goldÂźelds consistently exhibit intense fracturing of...quartz, phyllosilicates, organic matter, uraninite, gold, and base metal sulÂźde minerals, showing that all...at least partially epigenetic. Samples from Âźve goldÂźelds (Evander, West Rand, Carletonville, Klerksdorp...were basinwide events, rather than the result of local processes. Fluid inclusion data for the quartz indicates...the world-class gold mineralization in the Late Archaean Witwatersrand Basin, South Africa, remains a matter | | | Journal (article/letter/editorial) | and bitumen from the Ventersdorp Contact Reef, South Africa R. E. Zartman and H. E. Frimmel Department of...Sciences, University of Cape Town, Rondebosch, South Africa With 4Figures Received December 15, 1998; revised...auriferous conglomerate horizons (reefs) in the Witwatersrand Basin of South Africa are in many places cut by...contain sulphide, bitumen, and, less commonly, free gold. New Pb isotopic results for the Ventersdorp Contact...Siidafrika Die goldh/iltigen Konglomeratehorizonte (Reefs) im Witwatersrand Becken von Siidafrika werden vielerorts | | | Report (issue) | Genesis of Uraniun1- and Gold-Bearing Precan1brian Quartz-Pebble Congloinerates Proceedings of a Workshop...E R I I 6 I - A - BB GENESIS OF URANIUM- AND GOLD-BEARING PRECAMBRIAN QUARTZ-PEBBLE CONGLOMERATES...ore. Both actual size. A2 A. AB Reef, Denison Mine, Elliot Lake, Ontario. (Samples courtesy of V. Ruzicka...Leader Reef, about 1500 m depth, Blyvooruitzicht Gold Mine, Carletonville, Witwatersrand. (Sample courtesy...courtesy of D. K. Hallbauer, Chamber of Mines of South Africa ; radioluxograph by David M. Watson, Geological | | Mossman, D.J., Minter, W.E.L., Dutkiewicz, A., Hallbauer, D.K., George, S.C., Hennigh, Q., Reimer, T.O., Horscroft, F.D. (2008) The indigenous origin of Witwatersrand âcarbonâ. Precambrian Research, 164 (3) 173-186 doi:10.1016/j.precamres.2008.04.008 | Journal (article/letter/editorial) | Rondebosch 7700, South Africa c School of Geosciences, University of Sydney, Sydney, New South Wales 2006,...Macquarie University, Sydney, New South Wales 2109, Australia f Evolving Gold Corporation, Vancouver, British...approximately 40% of the gold is intimately associated with so-called âcarbonâ in âcarbon seam reefsâ, which occur...so-called âcarbonâ in the Archean Witwatersrand gold deposits has long been a contentious issue. However...is an important question because about 40% of the gold is intimately associated with the âcarbonâ (Nagy | | | Journal (article/letter/editorial) | deep and ultra-deep Witwatersrand mining areas, South Africa Received: 7 June 1996 / Accepted: 7 January...simultaneously, gaining in importance. Therefore, in order to mine deep orebodies in existing mines, as well as to...Mining Technology, PO Box 91230, Johannesburg, South Africa tersrand orebodies are mined in complex geological...major Witwatersrand orebodies. Introduction The gold resources of the Witwatersrand Basin (Fig. 1) are...continuously depleting. For example, in 1970 some 1266 t of gold (79% of world production) were produced from this | | | Journal (article/letter/editorial) | Mestorozhdenii, 2006, Vol. 48, No. 6, pp. 475â511. Gold-Bearing Reefs of the Witwatersrand Basin: A Model of Synsedimentation...genesis of the unique ore-bearing reefs of the Witwatersrand Basin and its gold resource potential are considered...Black, Ventersdorp Contact, Carbon Leader, and Vaal reefs, as well as of thermobarometric study of quartz...of synsedimentation hydrothermal origin of the reefs in the process of evolution of primary colloidalâdisperse...gain of deep ore-bearing gas-saturated fluids. The gold mineralization was formed under conditions of partially | | | Journal (article/letter/editorial) | ARTICLE H. E. Frimmel ĂĄ V. H. Gartz Witwatersrand gold particle chemistry matches model of metamorphosed...Analyses of gold particles from the Ventersdorp Contact Reef in the Klerksdorp and Carletonville goldÂźelds of...6 to 5.8 wt.%, respectively. However, individual gold particles are generally homogeneous. This observation...through gold at the peak metamorphic temperature of about 300 °C. The only exception is gold in hydrothermal...ascribed to the mobilisation of originally detrital gold particles during a chloritisation event that was | | | Journal (article/letter/editorial) | Springer-Verlag 1988 Composition of Gold Grains in the Vaal Placer, Klerksdorp, South Africa A. M. Reid 1 A. P. le...Town, Rondebosch, South Africa Abstract. Separated gold grains from 94 samples of the Vaal Placer, Klerksdorp...Klerksdorp gold field, South Africa have been analyzed for Au, Ag and Hg. Average gold grain compositions...homogeneous but significant differences exist between gold grains from single small samples and also between...samples. The data do not fit any simple model of gold compositional control by provenance or by metamorphic | | | Journal (article/letter/editorial) | grains in the Precambrian Witwatersrand conglomerate reefs are (Ir, Os, Ru) alloys. Osmium, iridosmine, osmiridium...minerals: rhodium sulfide and (Pt, Rh, Ru) alloy. Free grains of geversite,moncheite,sudburyite,and stibiopalladinite...burial, or even during later metamorphismof the reefs when sperrylite,hollingworthite, and related phasesprobably...(1964) examinedchemicallycleanedconVâąritwatersrand gold-bearingconglomerate reefshas centratesand suggestedthat..."iridosdescriptions have beenpublished. The first was by phases mine I" and "iridosmine II." lie found that both Young | | | Report (issue) | SURVEY OF SOUTH AFRICA COUNCIL FOR GEOSCIENCE GEOLOGICAL SURVEY OF SOUTH AFRICA MINERALOGY OF SOUTH AFRICA:... COUNCIL FOR GEOSCIENCE GEOLOGICAL SURVEY OF SOUTH AFRICA Scientific Editor R.D. Dixon Linguistic and...Council for Geoscience (Geological Survey of South Africa), 280 Pretoria Street, Silverton, Pretoria or........................... 69 5.1 Overview of South African Occurrences ..............................LAYEREDSUITE,BUSHVELDCOMPLEX.... 111 MINERALOGY OF SOUTH AFRICA: TYPE-MINERAL SPECIES AND TYPE-MINERAL NAMES | | | Journal (article/letter/editorial) | SouthAfrica T. UTTER Abstract The morphologyof the gold from the Proterozoic auriferous and uraniferous...and VentersdorpSystemsof the Klerksdorp gold field (South Africa) was studiedby meansof scanningelectronmicroscopy...types of gold could be distinguished;(1) detrital gold, (2) recrystallizedgold, and (3) gold associatedwith...The silver content, expressed in fineness, of the gold from various stratigraphic positionswas determined...scanning electron microscope. Initially the detrital gold was depositedafter being transportednot farther | | | Journal (article/letter/editorial) | Petrology © Springer-Verlag 1999 Printed in Austria Gold mobilizing fluids in the Witwatersrand Basin: composition...Cape Town, South Africa 2 Department of Geology, University of Stellenbosch, South Africa With 6 Figures...conglomerate horizons (reefs) in the late Archaean Witwatersrand Basin, South Africa. These data, supplemented...capable of mobilizing some of the primarily detrital gold in the fluvial Witwatersrand sediments. The dominant...source is inferred for the gold-mobilizing fluids in the Witwatersrand reefs because of a lack of Br- in | | | Journal (article/letter/editorial) | of hydrocarbons in the Witwatersrand Basin, South Africa: evidence from bulk and molecular d13 C data...Rondebosch 7700, South Africa Received 13 July 1999; accepted 10 March 2000 Abstract Gold in the quartzâpebble...conglomerates of the late Archean Witwatersrand Basin, South Africa, is often intimately associated with carbonaceous...ratio mass spectrometry; Goldâuranium deposits; Witwatersrand; South Africa 1. Introduction ) Corresponding... of the Late Archean Witwatersrand Basin in South Africa, the worldâs largest 0009-2541r01r$ - see front | | Guy, B. M., Ono, S., Gutzmer, J., Lin, Y., Beukes, N. J. (2014) Sulfur sources of sedimentary âbuckshotâ pyrite in the Auriferous Conglomerates of the Mesoarchean Witwatersrand and Ventersdorp Supergroups, Kaapvaal Craton, South Africa. Mineralium Deposita, 49 (6) 751-775 doi:10.1007/s00126-014-0518-3 | Journal (article/letter/editorial) | and Ventersdorp Supergroups, Kaapvaal Craton, South Africa B. M. Guy & S. Ono & J. Gutzmer & Y. Lin & N...conglomerates (reefs) in the Witwatersrand and Ventersdorp supergroups, Kaapvaal Craton, South Africa. Detailed...Detailed petrographic analyses of the reefs indicated that the vast majority of the buckshot pyrite grains...grains from the Main, Vaal, Basal, Kalkoenkrans, Beatrix, and Ventersdorp Contact reefs were analyzed for...from the Middelvlei and the Ventersdorp Contact reefs were measured for comparison. The ÎŽ34S, Î33S, and | | | Journal (article/letter/editorial) | Sciences, University of Cape Town, Rondebosch 7701, South Africa c GeoZentrum Nordbayern, University of Erlangen-NĂŒrnberg...uraninite in the Mesoarchean Witwatersrand Basin (South Africa), as well as for forensic purposes to track...the low solubility of Th4+, the only oxidation state of this element. Consequently, high-temperature...Archaean Dominion Group of the Kaapvaal Craton of South Africa (Rantzsch et al., 2011). Thus Th content in...occur in the Mesoarchaean Witwatersrand Basin in South Africa. We extended therefore our study to include | | | Journal (article/letter/editorial) | American Corporation of South Africa Ltd., Johannesburg, Republic of South Africa TU(~EKITE, Ni9Sb2Ss,...in the gold-bearing conglomerates of the Witwatersrand System (26~ S., 27 ~ E.), South Africa. The nickel...concentrate prepared from ore from the Vaal Reef, Vaal Reefs mine, Klerksdorp (Far West Witwatersrand)...Although rare free grains of tuSekite are found, the mineral is more commonly intergrown with gold, and in...in the Vaal Reef the mineral is also found intergrown with gersdorffite. Empirical formula of the Kanowna | | | Journal (issue) | performances by all of our mines including the Candelaria mine in Chile which commenced operations at the end of...Southside expansion at our mine in Morenci, Ariz: PD Mining Co's share of mine production from its worldwide...first half of 1994.The company's copper sales from mine production were 157,700st in the second quarter-including...Chambishi mine on the Copperbelt but regrettably no offers to buy the Chambishi underground mine were received...ZCCM said it will now continue to look after the mine on a care and maintenance basis while exploring | | | Journal (article/letter/editorial) | and PGE constraints on the timing and origin of gold mineralisation in the Witwatersrand Basin B.F. Schaefer...Department of Geological Sciences, Durham University, South Road, Durham, DH1 3LE, UK School of Geosciences...geochronology Platinum group elements Witwatersrand Basin Gold a b s t r a c t Analyses of the ReâOs isotope system...mineralisation in the Vaal Reefs section of the Witwatersrand Basin, the world's largest gold deposit. Consistent...associated with gold mineralisation suggests that the ReâOs isotope system was fractionated during gold mobilisation | | DepinĂ©, M., Frimmel, H. E., Emsbo, P., Koenig, A. E., Kern, M. (2013) Trace element distribution in uraninite from Mesoarchaean Witwatersrand conglomerates (South Africa) supports placer model and magmatogenic source. Mineralium Deposita, 48 (4) 423-435 doi:10.1007/s00126-013-0458-3 | Journal (article/letter/editorial) | from Mesoarchaean Witwatersrand conglomerates (South Africa) supports placer model and magmatogenic source...from various gold-bearing conglomerates of the Mesoarchaean Central Rand Group in South Africaâs Witwatersrand...potential source domain for some of the detrital gold in the Editorial handling: B. Lehmann Electronic...University of Cape Town, Rondebosch, Cape Town 7701, South Africa e-mail: hartwig.frimmel@uni-wuerzburg.de P....many other ore constituents, such as pyrite and gold, clear evidence of partial, short-range mobilisation | | | Journal (article/letter/editorial) | JANUARY-FEBRUARY,1980 No. 1 Sedimentological Controlsof Gold and Uranium in Two WitwatersrandPaleoplacers NORMAN...twomaâą-ginally economic unitswasundertaken 'to relate gold and uranium distributions to sedimentarytextures...proximal braided streams. On the local scale, good correlations exist between gold and uranium concentrations...componentsare concentratedby hydraulic processes. Gold/uranium ratios, however, are not consistentwith...depositswithin sandstonebeds.Two well-mineralized local depositsare examinedin detail: a multistoriedgravel | | | Report (issue) | 4/m 2/m 2/m. 20 ”m, partly replacing millerite and gold. As rims and irregular grains, to Physical Properties:...402(7) Z=1 X-ray Powder Pattern: Witwatersrand, South Africa. 2.76 (100), 2.38 (80), 2.28 (80b), 1.850 (80)...09 Te0.02 )ÎŁ=2.04 S8.00 . (2) Witwatersrand, South Africa; by electron microprobe, average of a range...in heavy mineral concentrates (Witwatersrand, South Africa); in serpentinites (Vozhmin massif, Russia)...pentlandite, magnetite, polydymite (Kanowna, Australia); gold, dyscrasite, michenerite, geversite, tetrahedrite | | England, Gavin L., Rasmussen, Birger, KrapezÌ, Bryan, Groves, David I. (2001) The Origin of Uraninite, Bitumen Nodules, and Carbon Seams in Witwatersrand Gold-Uranium-Pyrite Ore Deposits, Based on a Permo-Triassic Analogue. Economic Geology, 96 (8) 1907-1920 doi:10.2113/gsecongeo.96.8.1907 | Journal (article/letter/editorial) | Bitumen Nodules, and Carbon Seams in Witwatersrand Gold-Uranium-Pyrite Ore Deposits, Based on a Permo-Triassic...fly-speck carbon) in Late Archean Witwatersrand gold-uranium-pyrite ore deposits. Nodules in both contain...sandstones and quartz-pebble conglomerates (or reefs) of the Late Archean Witwatersrand basin has been...Witwatersrand gold production (Spangenberg and Frimmel, 1999). Although in most cases gold is not hosted...mineralization. Two forms of carbonaceous matter in reefs have long been known (Schidlowski, 1981): solitary | | | Journal (article/letter/editorial) | 1University of the Witwatersrand, Johannesburg, South Africa 2 CREGU, Vandoeuvre-L~s-Nancy, France With 9...widespread preservation of detrital uraninite and gold remobilization along major fluid conduits. Zusammenfassung...des Beckens auftritt und warum Remobilisiernng yon Gold entlang yon Zonen hoher Fluidwegsamkeit stattfinden...was deposited between 3074Ma and 2714Ma in the south-central portion of the Kaapvaal Craton. The depositional...economic concentrations of Au and U. Many conglomerate reefs nevertheless preserve detrital accumulations of | | | Journal (article/letter/editorial) | of the Witwatersrand Ore Region, Republic of South Africa A. A. Kremenetsky and I. E. Maksimyuk Institute...worldâs largest Witwatersrand auriferous region (South Africa) remains a debatable issue over several decades...worldâs largest Witwatersrand auriferous region (South Africa) remains a debatable issue over several decades...conglomerates account for 58% of the worldâs total gold reserves. Based on comprehensive geological and...ve process in the formation and localization of gold deposits and occurrences (Kremenetsky et al., 1997) |
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