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Harold K. Stager
Publications and source records attributed to Harold K. Stager.
Maps showing locations of holes drilled in 1948 and 1949 by U.S. Geological Survey, Calamity Mesa, Mesa County, Colorado
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Geology of the Calamity Mesa quadrangle, Mesa county, Colorado
The Calamity Mesa quadrangle is one of eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of southwestern Colorado. The geology of these quadrangles was mapped by the U.S. Geological Survey for the Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteen quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks the range in age from late Paleozoic to Quaternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults, and northwest-trending folds. Conspicuous among the folds are large anticlines having cores of intrusive salt and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uravan Mineral Belt". Individual deposits range in size from irregular masses containing only a few tons of ore to large tabular masses containing many thousands of tons. The ore consists largely of sandstone selectively impregnated and in part replaced by uranium and vanadium minerals. Most of the deposits appear to be related to certain sedimentary structures in sandstones of favorable composition.
Carnotite resources of the Calamity group area, Mesa County, Colorado
The Calamity group area, which includes 28 unpatented Government claims and enclosed fractions of public domain, lies along the east rim of Calamity Mesa, Mesa County, Colo. From 1915 through 1944, about 10,000 tons of carnotite ore, averaging about 1.0 percent U 3 O 8 and 2.5 percent V 2 O 5 , was produced from mines in this group (tons in this report are short tons). Production from this area from August 1949 to January 1, 1951, totaled 8,100 tons of ore with an average grade of 0.36 percent U 3 O 8 and 1.66 percent V 2 O 5 , containing about 58,600 pounds of U 3 O 8 and 268,000 pounds of V 2 O 5.