National Uranium Resource Evaluation: White Sulphur Springs Quadrangle, Montana

The geology of the White Sulphur Springs 1- by 2-degree quadrangle, Montana, was evaluated to identify geologic environments and delineate areas favorable for the occurrence of uranium deposits. Determination of favorability was based upon criteria developed for the National Uranium Resource Evaluation program. Uranium occurrences were located, examined, sampled, and described. Areas containing potentially favorable geologic environments were examined and sampled. Results of the sample analyses, aerial and surface radioactivity measurements, and data from surface investigations and well logs, combined with information from the literature, were used to evaluate the potentially favorable environments. Results of the study show three environments to be favorable for uranium deposits. The Renova Formation in the Helena and Townsend basins is favorable for Wyoming roll-type deposits. The Boulder batholith is favorable for vein-type deposits of magmatic-hydrothermal, hydroallogenic, or authigenic origin. The Lakota sandstone and other sandstones in the Kootenai Formation are favorable for Wyoming roll-type deposits in the Wheatland and Judith basins.