Unnamed (near Fog Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au; Zn
Other commodities Ag; Ni
Ore minerals pyrite

Geographic location

Quadrangle map, 1:250,000-scale TK
Quadrangle map, 1:63,360-scale D-4
Latitude 62.7597
Longitude -148.5824
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 1,500 feet on the north bank of Fog Creek, 1.4 miles south-southeast of hill 2630. The location is accurate to within 1/4 mile.

Geologic setting

Geologic description

The rocks in the area of this occurrence are Triassic(?) limestone, siltstone and chert, with very fine grained, crossbedded, dark gray limestone and gray argillite interlayered with dark red weathering, gray-green chert (J. Schmidt, written communication, 2001). Locally, yellow-green-weathered material occurs below limestone horizons and red-weathering, altered material occurs in limestone- siltstone outcrops. Chert and shale are marked by yellow efflorescence, and interlayered gray argillite and chert are marked by white efflorescence. Iron-stained, silicified argillite contains 2-3 percent fine-grained pyrite. Samples of altered sedimentary rocks contain up to 1,110 parts per million zinc, 0.4 part per million gold, 1.1 parts per million silver, and 205 parts per million nickel (J. Schmidt, written communication, 2001).
Geologic map unit (-148.584642278126, 62.7592262078969)
Alteration of deposit Zones of red or yellow-green weathering or alteration; yellow and white efflorescence; and iron staining (J. Schmidt, written communication, 2001).

Production and reserves

Workings or exploration Only surface sampling by U.S. Geological Survey (J. Schmidt, written communication, 2001).
Indication of production None

References