| | Journal (article/letter/editorial) | uraninite in the natural fission reactors in Gabon J. ‘Department JANECZEK’ and R. C. EWING’ ‘Faculty of...uranium ore from the natural fission reactors in Gabon were studied by detailed electron microprobe analysis...Ru. INTRODUCTION it has also been recognized at Oklo (Havette et al., 1975; Lancelot et al., 1975; Devillers...loss from uraninite, the U-P\, ages of U ore at Oklo range from 1780 Ma to 2050 Ma (Naudet, 1991). A...1993b). The major episode of Pb mobilization at Oklo has been related to the intrusion of a dolerite | | | Journal (article/letter/editorial) | radiolysis on local redox conditions in the Oklo, Gabon, natural fission reactors 10 and 16 CREGU VI~RONIQIJE...significantly modify the local redox conditions. The Oklo natural fission zones are good examples where the...claimed that, in the conditions of the operating Oklo reactors, there had been the same recombination...matter was not considered in these calculations. The Oklo nuclear fission zones are excellent sites for studying...spectroscopy. r c Libreville c GABON 1 t r Q 500 m i OKLO \ - ’ _,.., . . . 6 Manganese 0 | | | Journal (article/letter/editorial) | fissiogenicREEs from a natural fission reactor at Bangomb6,Gabon hxusz JlNsczrrt .nxoRonNrv C. Ewrxc2 'Faculty of...florencite-(Ce)contain inclusions of thorite, chalcopyrite, and galena.Florencite-(La) was found 5 cm from...deposits of the Franceville Basin in southeastern Gabon at approximately2 Ga andlasted 105-106yr, producinga...fission-reactor zones have been discovered in the U deposit at Oklo since 1972. Two more reactorsare known at Okelobondo...Okelobondo and Bangomb6, some 0.5 and 20 km south of Oklo, respectively. The Bangomb6 fission reactor, discovered | | | Journal (article/letter/editorial) | 323--336 (1972) © by Springer-Verlag 1972 La province urani~re du bassin de Franceville (R6publique...sedimentary series of the Franceville Precambrian basin (Gabon Republic) consists of two successive sandstony-pelitic...1958 et F. WEBER 1969; Echelle: 1/5.000.000 La province uranif4re Les travanx de reconnaissance se poursuivent...COMUF); j. BouRae~ et J. P. PFIFFEL.~IANN:La province uranifhre Episode p41itique Flb Annonc& par tes...succession g4n4rale des facihs est la suivante de bas en haut: Conglom6rat fl galets de pdlites remani4es (Mounana) | | | Journal (article/letter/editorial) | italics; book reviews are placed at the end. Acid-mine drainage (AMD), relationships of soluble, suspended...Argentopentlandite, enclosed within early tin-bearing chalcopyrite from the Northern Pennine Orefield, 317 Armalcolite...assemblage from the Tertiary Barrington volcanic province, New South Wales, 623; no61bensonite a new BaMn...silicate of the lawsonite structure type, from Woods mine, New South Wales, 369; solid solution and composi-...mineral of the lawsonite structure type, from Woods mine, New South Wales, Australia, 369 BARKOV.A., 973 | | Rantzsch, Ulrike, Gauert, Christoph D. K., Van der Westhuizen, Willem A., Duhamel, Isabelle, Cuney, Michel, Beukes, Gerhard J. (2011) Mineral chemical study of U-bearing minerals from the Dominion Reefs, South Africa. Mineralium Deposita, 46 (2) 187-196 doi:10.1007/s00126-010-0317-4 | Journal (article/letter/editorial) | (*) : W. A. Van der Westhuizen : G. J. Beukes Department of Geology, University of the Free State, P.O...and Upper Reef) were mined underground at Rietkuil Mine by Uranium One Africa Ltd from 2006 to 2008. The...a 700–800 m thick volcanosedimentary unit in the mine area (Fig. 2), underlies the Witwatersrand Supergroup...sample 5510. c Microphotographs of sphalerite, chalcopyrite, galena, Ni–Co–sulfarsenide and a U–Ti phase...Magnetite Pyrite Galena Arsenopyrite Sphalerite Chalcopyrite Pyrrhotite Garnet Quartz Sericite Chlorite Gold | | | Journal (article/letter/editorial) | Ma ago. The model explaining the formation of the Oklo uranium deposits suggests that at the time of sediment...Paleoproterozoic; Uranium; Manganese; Atmosphere; Oklo; Gabon; Carbon isotopes; Black shales 1. Introduction...Introduction The natural nuclear fission reactors in Gabon are unique. The possibility that nuclear fission reactions...occur 2.0 Ga ago in the Oklo uranium deposit of the Francevillian Series, Gabon (Neuilly et al., 1972)...in the Paleoproterozoic uranium ore deposits of Gabon. This observation raises the question whether this | | | Report (issue) | deposits of Mas Laveyre (France) and Mikouloungou (Gabon). 5 3. Hematite breccia complex deposits: Deposits...activities include drilling and coring to complete final mine plans and establish final processing flowsheets...case of an underground mine or overburden stripping in the case of an open pit mine, mill construction,...direction and dips south at 15–30º. In the Main Mine Series the ore zone is up to 35m thick. Jabiluka...open to the south and east at depth. In the Main Mine Series the ore zones are up to 135m thick. The metasedimentary | | | Journal (article/letter/editorial) | Deditius, Satoshi Utsunomiya, Rodney C. Ewing * Department of Geological Sciences, University of Michigan...been described in sedimentary U-deposits at Oklo, Gabon, and unconformable U-deposits within Athabasca...of As in uraninite from the widely cited Nopal I mine (Janeczek et al., 1996; Finch and Murakami, 1999)...Rocky Mountain and Intermountain Basin Uranium Province, USA (Dahlkamp, 1993; Finch, 1996) (Fig. 1). The...different ages for the rock units at the Lookout Mine: 94, 99, and 203 Ma using the U–Pb method, and suggested | | | Report (issue) | DepositsProgram and Abstracts Konstantin graphite mine, Velke Vrbno, Czechoslovakia. Graphite is hosted...2 54 U.S. GEOLOGICAL SURVEY Cl RCULAR 1037 DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary...Witwatersrand, South Africa; Elliot Lake, Canada; and Oklo, Gabon Bartholomew Nagy VIII PROGRAM OF LECTURES...Deposits By E.S. Ho, R.M. Kettler, and P.A. Meyers, Department of Geological Sciences, University of Michigan...StatePreliminary Results By Timothy W. Lyons, Department of Geology and Geophysics, Yale University, New | | | Journal (article/letter/editorial) | os de Caldas, Cigar Lake, Maqarin, El Berrocal, Oklo and Palmottu. To make this comparison meaningful...primary uranium mineralisations (Enresa, 1996); Oklo (Gabon), a fossil natural nuclear reactor systems located...carried out to date. For example, the studies at Oklo and Palmottu were completed only during 1999. Consequently...BPM exercises, from the Pocß os de Caldas to the Oklo and Palmottu projects, has not varied significantly...(Spain), CSIC (Spain) and MBT/QuantiSci (Spain). Oklo: CEA (France), Ciemat (Spain), CNRS (France), CSIC | | | Journal (article/letter/editorial) | Through the process known as acid rock drainage (or mine drainage), the oxidative dissolution is in this...complex outer layer of of sulfides from ores and from mine wastes can release air, water, biota, organic matter...supergene oxidation and leaching of ore deposits and mine wastes. They have a profound effect on high pressures...geochronologic studies. For overall viability of the mine. This has been the case since example, one could...deposits and thereby determine long-term rates 1 Department of Geology, FCFM, Universidad de Chile Plaza | | Kirchenbaur, Maria, Maas, Roland, Ehrig, Kathy, Kamenetsky, Vadim S., Strub, Erik, Ballhaus, Chris, Münker, Carsten (2016) Uranium and Sm isotope studies of the supergiant Olympic Dam Cu–Au–U–Ag deposit, South Australia. Geochimica et Cosmochimica Acta, 180. 15-32 doi:10.1016/j.gca.2016.01.035 | Journal (article/letter/editorial) | within a granite of the 1.59 Ga Gawler Silicic Province. Emerging evidence indicates that both the breccia...and Weber, 2003), of the type discovered at the Oklo uranium deposit (e.g., Naudet, 1974; Gauthier-Lafaye...and apatite. The major sulphides are pyrite, chalcopyrite, bornite, chalcocite (e.g., chalcocite, digenite...→ barite, (3) sphalerite→ galena → pyrite → chalcopyrite → bornite → chalcocite → nonsulfide, and (4)...fluorite, siderite, barite, chalcocite, bornite, chalcopyrite and pyrite. Absolute abundances and relative | | | Journal (article/letter/editorial) | Gels from the Reactor Zone Z13 of the Oklo Uranium Deposit (Gabon) Yu. M. Dymkova, V. T. Dubinchukb, Academician...zone Z13, as well as 16 other reactor zones of the Oklo deposit and adjacent areas, occurs in sandstone...polished section etched by concentrated nitric acid. Oklo, Z13, Sample SD.37S2/SD. interest grew under...called gelminerals (e.g., gelmar casite, gelchalcopyrite, and others; in our case, gel pitchblende)...anisms of the formation of gelpitchblende nodules in Oklo ores only on the ontogenetic level using the known | | | Journal (article/letter/editorial) | Francevillian(Lower Proterozoic)Uranium Ore Depositsof Gabon F. GAUTHIER-LAFAYE AND F. WEBER Centrede Sddimentologie...lowerProterozoicuraniumore depositsin the Francevillebasin(Gabon)are the oldest high-gradeuraniumaccumulations known...asdefinedbyWinkler THE Francevillian uranium ore depositsat Oklo are gradepressure axisin the cenwell knownbecausethey...(Bonhommeet al., 1982; Gauthier-Lafaye, in southeastern Gabon and rests on the Archean 1986). (2,700 Ma) basementrocksof...Geologicmap of Gabon.Insert showsthe locationof Gabon in Africa. teau,the StanleyPool,andthe Batekeplateauseries | | | Report (issue) | UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY PRINCIPAL URANIUM DEPOSITS OF THE WORLD ...Angola, Peoples Republic of........................ Gabon, Republic of................................. Central...Saskatchewan, Canada; the Shinkolobwe, Katanga Province, Zafre; and the medium-sized deposits at Joachymov...Joachymov, Czechoslovakia, and at Schwartzwalder mine, Colorado, U.S.A.). Uranium deposits have been found...Australi a Sweden Spain France Ni ger Argenti na India Gabon Al geri a Yugoslavia Brazil Central African Republic | | | Report (volume) | Editors: Peter C. Burns' & Robert Finch 2 1 Department of Civil Engineering and Geological Sciences...Environmental issues such as coping with uranium mine and mill tailings and other uranium-contaminated...and Geochemistry of Natural Fission Reactors in Gabon Janusz Janeczek 8 393 Geomicrobiology of Uranium...and Geochemistry of Natural Fission Reactors in Gabon Janusz Janeczek INTRODUCTION: NATURAL FISSION REACTORS...largest construction projects in the history of the Department of Energy. Approximately three billion dollars | | | Journal (issue) | Jianghshan, Guangdong Province. I have seen others listed as coming from Hebei Province. Regardless of where...4 Fig. 1. Apophyllite, Jianghshan, Guangdong Province, China, photo by Dan Weinrich. neat piece. To...the old classic locality, Morgabal, in Aveyron Department, France. Also, he had small trays holding small...stibnites from a new Nevada locality, the Murray Mine, not the old Manhattan, but he had only three specimens...clear calcites from a small pocket in the Meikle Mine, the new locality for the superb yellow barites | | | Report (issue) | National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161; please include... U.S. GEOLOGICAL SURVEY CIRCULAR 1058 U.S. DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary...investigations of a natural reactor and its environs at Oklo, Gabon-A preliminary report, by Bartholomew Nagy, Joel...Sucha Rudna in Czechoslovakia. In the Nevada gold province, auriferous Paleozoic black shales are part of... deposits near Songlin, Zunyi County, Guizhou Province, in the People's Republic of China have been mined | | | Journal (article/letter/editorial) | Mina,b,*, Changquan Fanga, Mostafa Fayekc a Department of Earth Sciences, State Key Laboratory of Mineral...Nanjing 210093, People’s Republic of China c Department of Earth and Planetary Sciences, University of...aggregates are marcasite, sphalerite, galena, chalcopyrite, bornite, clausthalite, microcrystalline quartz...China 1. Introduction * Corresponding author. Department of Earth Sciences, State Key Laboratory of Mineral...deposits. The district is located in the Jiangxi Province, SE China, and is one of the most economically | | Macmillan, Edeltraud, Cook, Nigel J., Ehrig, Kathy, Ciobanu, Cristiana L., Pring, Allan (2016) Uraninite from the Olympic Dam IOCG-U-Ag deposit: Linking textural and compositional variation to temporal evolution. American Mineralogist, 101 (6) 1295-1320 doi:10.2138/am-2016-5411 | Journal (article/letter/editorial) | is found in “natural fisson reactors” such as Oklo (Gabon; Janeczek and Ewing 1995), but PbO contents of...South Australia) is part of the Olympic Cu-Au-(U) province in the eastern Gawler Craton (e.g., Skirrow et...lateral (from periphery to center) as: chalcopyrite-pyrite, chalcopyrite-bornite, bornite-chalcocite, and chalcocite;...chalcocite, bornite, and chalcopyrite (XMOD data); and (d) pyrite, bornite, and chalcopyrite (XMOD data). analytical...fine-grained “dusting” of U-minerals (in hematite or chalcopyrite) S3 RX7255 RD1305 691.0 364 2 16 82 GRNL Fine-grained | | Riegler, Thomas, Beaufort, Marie-France, Allard, Thierry, Pierson-Wickmann, Anne-Catherine, Beaufort, Daniel (2016) Nanoscale relationships between uranium and carbonaceous material in alteration halos around unconformity-related uranium deposits of the Kiggavik camp, Paleoproterozoic Thelon Basin, Nunavut, Canada. Ore Geology Reviews, 79. 382-391 doi:10.1016/j.oregeorev.2016.04.018 | Journal (article/letter/editorial) | author, present address Trinity College Dublin, Department of Geology, NU College Green, Dublin 2, Ireland...Kyser MA 2006). By comparison, in the 1.74 Ga Oklo deposit of the Paleoproterozoic Franceville Basin...a Phanerozoicstyle diagenetic system. Faults at Oklo played key roles by creating traps and/or paths...uraninite (UO2), coffinite (U(SiO4)1-X OH4x), TE chalcopyrite (CuFeS2), johannite [Cu(UO2)(SO4)2(OH)2.8H2O)]...taken TE place to precipitate uraninite and chalcopyrite. Such drastic, local reducing conditions could | | | Journal (article/letter/editorial) | transport through two mixing zones affected by acid mine drainage near Silverton, Colorado— Laurence E. Schemel...deposit of the Shuikoushan mineral district, Hunan Province, China— Nanshi Zeng, E. Izawa, Y. Motomura, and...101 Complexly zoned fibrous tourmaline, Cruzeiro mine, Minas Gerais, Brazil: A record of evolving magmatic...Evidence for a Cambrian diamondiferous alkaline province in northeastern North America—Stéphane Digonnet...and remedial measures at the Troya abandoned Pb-Zn mine (The Basque Country, Northern Spain) —V. Iribar | | | Journal (article/letter/editorial) | uraniumthat theycanopt to exportß Anstralia, Canada, Gabon, Niger, and South Africa (includingNamibia). Anstraliahasby...(<$30/1b UaOs) Canada, South Africa USA, Niger, Gabon Australia, Canada, France Namibia Australia 500...UaOs are known,and the capitalinvestmentrequiredto mine such depositsis nmch higher and riskier than for...Canada 20 184 igneous conglomerate,vein France Gabon India 41 22 33 vein sandstone vein Niger South...reservesplus productionof 25,000 to 40,000 the Pitch mine. Colorado; and the Sherwoodmine, short tons UaOs | | Read, David, Andreoli, Marco A.G., Knoper, Mike, Williams, C. Terry, Jarvis, Neil (2002) The degradation of monazite: Implications for the mobility of rare-earth and actinide elements during low-temperature alteration. European Journal of Mineralogy, 14 (3) 487-498 doi:10.1127/0935-1221/2002/0014-0487 | Journal (article/letter/editorial) | study was undertaken at the Steenkampskraal monazite mine, South Africa. Steenkampskraal is among the richest...common with other mineral deposits in the region. The mine was first in operation from 1952 to 1963 when it...contamination, are likely to be processed should the mine be re-opened at some time in the future This paper...General geology of the Steenkampskraal monazite mine, South Africa (modified after Andreoli et al., 1994...Location of study area (NMC – Namaqualand Metamorphic Province). 1980; Maruéjol et al., 1990) have tended to |
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