Application of mineral-solution equilibria to geochemical exploration for sandstone-hosted uranium deposits in two basins in west central Utah

A geochemical survey utilizing mainly ground waters was conducted in the Milford and Beaver basins. Waters were collected mainly from wells and springs at 100 sites and analyzed for major and minor elements. A computer model (WATEQ3) was used to calculate the redox potential and the state of saturation of the waters with respect to uraninite, coffinite, and other mineral phases. Several areas in the basins were shown to have ground-water environments of reducing redox potentials which are favorable for precipitation of reduced uranium minerals. In addition, the ground waters in some of these areas were shown to be saturated or near saturation with respect to uraninite and coffinite. These areas do not necessarily coincide with areas containing the highest concentrations of uranium in ground water. The methods described in this study for hydrogeochemical exploration for sandstone-hosted uranium deposits may have wide application, particularly throughout those filled basins in the western United States where nearby sources for uranium exist.