Characteristics of uranium mineralization in the Tin-Seririne sedimentary basin (Algeria)

Abstract

This article presents the results of studying the uranium mineralization of various parts of the Tin-Seririne sedimentary basin located in the southern part of the Hoggar massif in south-eastern Algeria. Mineralization of uranium is localized at different stratigraphic levels: in altered rocks of the Archean basement and unconformity overlying basal conglomerates (Tahaggart region), and in Devonian sandstones (uranium ore occurrences Tamart-N-Iblis, Timouzaline, etc.). For laboratory studies, 07 samples were taken: As and A1 granites, Tedjart, Timouzaline and Tamart-N-Iblis sandstones, gneisses and conglomerates of the Tahaggart deposit. The samples were examined using gamma spectrometric, chemical and microprobe analyzes. Mineralization is represented by minerals of hexavalent uranium: autunite, torbernite, carnotite, vanuralite and uranophane. The hypergenesis zone of the deposit, it is noted that the geochemical features of the formation of uranium mineralization are typical for regions of arid climate. The arid climate corresponds to oxidative processes of chemical weathering, with weakly alkaline or neutral uranium-bearing solutions. When studying samples taken from different stratigraphic levels, a difference in mineral composition was noted, which indicates some differences in the conditions of formation of uranium mineralization.