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Nicholas T. Zilka

Publications and source records attributed to Nicholas T. Zilka.

4 recordsLinked to original sources
USGS1983

Mineral resource potential map of the Selway-Bitterroot Wilderness, Idaho County, Idaho, and Missoula and Ravalli counties, Montana

Mineral resource studies by the U.S. Bureau of Mines and the U.S, Geological Survey indicate that five areas within the Selway-Bitterroot Wilderness have mineral resource potential. Regional studies suggest that three granitic plutons within the wildemess, the Running Creek pluton on the southwestern border of the wildemess, the Painted Rocks pluton on the southern border of the wildemess, and the Whistling Pig pluton in the west-central portion of the wildemess, have low potential for molybdenite deposits, but detailed surface investigations failed to recognize a deposit. Placer deposits in the Elk Summit area on the north side of the wildemess contain subeconomic resources of niobium- (columbium-) bearing ilmenite. A vein on the northeast side of the wildemess at t~e Cliff mine at Saint Joseph Peak contains subeconomic silver-copper-lead resources. The wilderness has no known potential for oil and gas, coal, geothermal resources, or other energy-related commodities.

Idaho, Montana↗
USGS1977

Mineral resources of the Sheep Mountain Wilderness study area and the Cucamonga Wilderness and additions, Los Angeles and San Bernardino counties, California

A mineral survey of the Sheep Mountain Wilderness study area and Cucamonga Wilderness area and additions by the U.S. Geological Survey and Bureau of Mines in 1975 covered about 66,500 acres (26,500 ha) of the San Bernardino and Angeles National Forests in southern California. The two study areas are separated by San Antonio Canyon. The mineral resource potential was evaluated through geological, geochemical, and geophysical studies by the Geological Survey and through evaluation of mines and prospects by the Bureau of Mines.

California↗