Economic geology of uranium deposits in the Ralston Creek area Jefferson County, Colorado
The deposits described are in Golden Gate Canyon and the Ralston Creek drainage area near Denver, Colorado. Two of the deposits have produced uranium ore as of March 31, 1956. The Ralston Creek mine has shipped 2,338 tons averaging 0.72 percent U/sub 3/O/sub 8/ and the Gary shipped 1,108 tons averaging 0.28 percent U/sub 3/O/sub 8/. The country rock includes metasediments of the Idaho Springs formation of Precambrian age. The pitchblende deposits are associated principally with two well-foliated rock types, hornblende gneiss and quartz-biotite gneiss and with granite pegmatite. The Rogers and Hurricane Hill breccia reefs, large northwest trending Tertiary faults, cross the area. Numerous secondary fractures, formed contemporaneously with the reefs, were selectively mineralized to form the known deposits. Hornblende gneiss and quartz-biotite gneiss are the most favorable wall rock types for the development of ore. Hydrothermal solutions attacked the wall rock along the veins to produce propylitization, sericitization and silicification. Quartz and pyrite preceded pitchblende. Ankerite was deposited during the pitchblende phase and continued until after the formation of copper, lead and zinc sulfides. Ore controls for the deposition of the uranium are postulated, depending on whether the introduced solutions were in a state of oxidation or reduction. Suitable structural traps provided a favorable environment for the localization of uranium and associated metals. 14 figures.
- Research Organization:
- Bendix Field Engineering Corp., Grand Junction, CO (USA)
- OSTI ID:
- 7235853
- Report Number(s):
- RME-1077
- Country of Publication:
- United States
- Language:
- English
Similar Records
National Uranium Resource Evaluation, Glens Falls Quadrangle: New York, Vermont, and New Hampshire
Alteration and vein mineralization, Schwartzwalder uranium deposit, Front Range, Colorado