Botanical prospecting for uranium in the Circle Cliffs area, Garfield County, Utah
Astragalus pattersoni and Stanleya pinnata broadly define some uraniferous localities adjacent to the contact of the Moenkopi formation and the Shinarump member of the Chinle formation, but the general paucity of Astragalus in the Circle Cliffs area limits the usefulness of this genus. Astragalus pattersoni , Stanleya pinnata , and Aster venustus (?) may serve as guides to mineralized parts of the Salt Wash sandstone member of the Morrison formation in the Circle Cliffs area. Thick and thin sandstones of the Shinarump member generally can be distinguished by pinyon-juniper ration studies. These studies may supplement drilling to define channel-fill sandstones which are associated with ore deposits in the Circle Cliffs area. Ratio studies appear to be applicable to other areas throughout the Colorado Plateau where similar geological and ecological conditions exist.