Determinations were made of the leachable uranium content of soil and rock samples from the vicinity of the Standard-Lisbon-Cal Uranium ore body, Big Indian Wash, Utah, the new Monument No. 1 ore body, Oljetoh, Arizona, a Shinarump and a Chinle deposit near Cameron, Arizona, and the Freedom No. 1 and No. 2 ore bodies near Marysvale, Utah. In the sedimentary uranium deposits studied the presence of uranium mineralization can be detected at considerable horizontal distances from ore, but surface samples at vertical distances of more than about 30 feet from ore gave no indication of the presence of ore at depth.At Marysvale uranium was found to penetrate no farther than alteration visible in hand-specimen into the quartz monzonite wall rock of a uraninite-fluorite vein. Analyses of surface samples indicate that mineralization at the base of late Tertiary rhyolite can be detected at the surface through a fair thickness of rhyolite.The data as a whole suggest that in areas in which uranium ore is present at shallow depths leachable uranium analyses can serve as a useful tool in exploration.