Towards a Mineral Systems Model for Surficial Uranium Mineralization Based on Deposits in the Erongo District of Namibia

Surficial deposits in Namibia’s Erongo district contain substantial but low-grade resources of uranium and vanadium (nearly 500 Mlb U3O8), hosted palaeochannels. This review attempts to develop a mineral systems model for the deposit type, it is emphasised that research into this important class has been minimal since nineteen eighties, largely as result limited investment exploration. The are groundwater movement aquifers developed within Cenozoic source was probably granitic rocks traversed by these palaeodrainages, particularly black-quartz rich pegmatites similar those make up hard-rock alaskite region. Transport generally assumed have occurred aqueous species after palaeochannels became filled with sediment. U-enriched clasts yet be investigated local uranium. localised deposition regionally extensive carbonate cementation palaeochannel sediments, which climate change (aridification). Pre-uranium calcite may acted chemical buffer (pH) influenced hydrology, restricting flow deeper portions. Uranium paragenetically related Mg clays dolomite, suggesting evolved more Mg-rich composition during deposition, extreme evaporation. controls on localisation mineralisation remain unclear unpredictable, grade—the fundamental determinant economic viability. There few absolute age determinations any deposits, none occur likely older than Miocene. reflects low preservation potential. For example, Langer Heinrich incised active drainage attendant erosion probable removal mineralised material.