URANIUM MINERALIZATION IN THE GOLIAD FORMATION OF THE KINGSVILLE DOME IN SITU LEACH URANIUM MINE IN KLEBERG COUNTY, TEXAS

摘要

Most of the bedload fluvial sandstones of the Miocene Goliad Formation in the subsurface of the Kingsville Dome uranium mine area are litharenites and are host to uranium minerals in "roll-front" uranium deposits. The uranium roll-fronts occur in fluvial channel-fill deposits and the ore bodies formed when uranium-enriched groundwater invaded a zone that had been reduced by methane and hydrogen sulfide gases. These gases most likely migrated upwards through faults from deeper hydrocarbon reservoirs. The uranium ore occurs as uraninite and amorphous uranium in detrital iron-titanium oxide minerals which were subsequently replaced by marcasite, pyrite and titano-magnetite in the sand-size volcanic fragments, in diagenetic montmorillonite clay, and on the surfaces of thin authigenic Ca-montmorillonite clay coats surrounding quartz sand grains.