The U.S. Geological Survey explored Outlaw Mesa for carnotite deposits from 1949 through 1951 with 1,302 diamond-drill holes that totaled 222,150 feet.
Total production from Outlaw Mesa from 1914 through 1951 was about 30,000 short tons of carnotite ore, having an estimated grade of about 0.40 percent U3O8 and 1.7 percent V205.
The known carnotite deposits are in a number of sandstone lenses in the upper part of the Salt Wash sandstone member of the Jurassic Morrison formation.
The deposits are mainly impregnations of sandstone by carnotite and vanadium-bearing clay minerals. Commonly, the deposits are irregular tabular layers or pod-like or crescentic masses ("rolls") connected by thin layers of mineralized rock. The deposits and rolls have a dominant northeasterly trend.
Useful criteria for recognizing-sandstone that might contain mineralized rock are: (1) thick, light-brown sandstone, (2) gray mudstone at the base of and in this sandstone, and (3) abundant carbonaceous material.
The indicated and inferred reserves of carnotite-bearing material, and the pounds of contained U308 and V205 are summarized in table 1. Potential reserves, whose existence is based on geologic evidence alone, are estimated to total about 80,000 short tones, averaging about 0.35 percent U308 and 1.5percent V205.
No further exploration by the Geological Survey is planned; however, additional drilling by private operators is recommended, particularly in ground underlain by mineralized rock.
