This report is a preliminary evaluation of the uranium resources of the Brushy Basin Member of the Morrison Formation of Late Jurassic age in southwestern Colorado and southeastern Utah. The project, which began July 1, 1976, and was completed October 1, 1976, was carried out by the Bendix Field Engineering Corporation (BFEC) for the Grand Junction Office of the U.S. Energy Research and Development Administration (ERDA).

Supplementary data containing locations of uranium deposits in the Brushy Basin project area, Utah and Colorado.

From introduction: This report describes work done in the Denver and Greeley National Topographic Map Series (NTMS) quadrangles (1:250 000 scale) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From summary: The University of Colorado, under contract with the Los Alamos Scientific Laboratory (LASL), is currently performing an evaluation of geochemical relationships of water and sediments and seasonal variations to uranium for the South Platte drainage of northeastern Colorado. As a preliminary part of this study, samples were collected from 125 sites near Sterling and Fort Morgan, Colorado, during the period from December 20, 1976, to January 15, 1977. During this period the weather in the area was clear to partly cloudy, with daytime temperatures ranging from -12 to 12 C. Only a trace of precipitation, in the form of very light snow flurries, occurred during the sampling period. The sample site locations and numbers (the first two digits have been omitted) are shown on Plate I.

Analysis of geologic, hydrologic, and geophysical data obtained in and around Yellow Creek core hole No. 1, Rio Blanco County, Colorado, indicate a 1,615-foot section of oil shale was penetrated by the hole. Geophysical log data indicate the presence of 25 gallons per ton shale for a thickness of 500 feet may be marginal. The richest section of oil shale is indicated to be centered around a depth of 2,260 feet. Within the oil shale the interval 1,182 to 1,737 feet is indicated to be relatively structurally incompetent and probably permeable. Extension of available regional hydrologic data indicate the oil shale section is probably water bearing and may yield as much as 1,000 gallons per minute. Hydrologic testing in the hole is recommended.

Discussing the geologic setting of the Foothills Mine, Idledale District, Jefferson County, Colorado

Discussing a reconnaissance carried out for uranium in parts of the San Juan Basin in New Mexico and Colorado