Uranium in the Marysvale volcanic field is known to occur in several geologic environments, and is hypothesized to occur in others. Together the known and hypothetical occurrences range from a source in rhyolite magma, through porphyry-type deposits, hydrothermal vein deposits, dispersed hydrothermal deposits, and after transport in ground and surface water, to roll-front or sedimentary trap-deposits in basin-fill sediments. To date, only the hydrothermal vein environment has been productive, but billions of pounds of uranium were available in all other environments, and if proper circumstances occurred, significant concentrations probably exist there too. The intracaldera fill of the Mount Belknap caldera and sediment-filled basins adjoining the Tushar Mountains are especially favorable for the undiscovered uranium that may be expected.