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Phosphatian coffinite with rare earth elements and Ce-rich françoisite-(Nd) from sandstone beneath a natural fission reactor at Bangombé, Gabon

Published online by Cambridge University Press:  05 July 2018

Janusz Janeczek  and
Rodney Ewing
Janusz Janeczek
Affiliation:
Department of Earth Sciences, University of Silesia, ul. Bedzinska 60, PL-41-200 Sosnowiec, Poland
Rodney Ewing
Affiliation:
Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131-1116, USA
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Extract

Spontaneous fission reactions occurred in several uranium deposits in SE Gabon approximately two billion years ago. The reactor zones, between 10 to 50 cm thick, are found in Proterozoic sandstones and consist of high-grade uranium ore mantled by illite and/or chlorite (Gauthier-Lafaye et al., 1989). During a mineralogical study of sandstones (quartz arenites) underlying a natural fission reactor at Bangombé (20 km south of the Oklo uranium deposit), we have found several grains of a uranous silicate, coffinite, with unusually high concentrations of phosphorous and enriched in light rare earth elements (LREE).

Keywords

phosphatian coffinitefrançoisite-(Nd)fissiogenic REEGabonnatural reactor
Type
Short Communications
Information
Mineralogical Magazine , Volume 60 , Issue 401 , August 1996 , pp. 665 - 669
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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