Unnamed (west of Squaw Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Cu
Other commodities Mo
Ore minerals bornite

Geographic location

Quadrangle map, 1:250,000-scale MC
Quadrangle map, 1:63,360-scale C-8
Latitude 61.5698
Longitude -143.894
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is west of Squaw Creek on the north valley wall of the Kuskulana River. It is at an elevation of about 3,900 feet, 2,800 feet east of elevation 4765, and 2,700 feet northeast of the center of section 35, T. 3 S., R. 8 E. of the Copper River Meridian. This is locality 140 of MacKevett (1976) and locality 30 of MacKevett and others (1978). The location is accurate to within about 100 feet.

Geologic setting

Geologic description

This occurrence consists of bornite-bearing veins up to 6 centimeters thick that are localized in a 2-meter-wide, altered fault zone cutting Triassic Nikolai Greenstone (MacKevett, 1976). A sample of the mineralization contained 200 parts per million (ppm) silver, more than 20,000 ppm copper, and 7 ppm molybdenum. The widespread deposition of copper in Triassic greenstone and limestone of the area is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic or Early Cretaceous (MacKevett and others, 1997). Copper-bearing minerals were deposited in the underlying Nikolai Greenstone at about 112 Ma (Silberman and others, 1980).
Geologic map unit (-143.896087269016, 61.56933588211)
Mineral deposit model Basaltic Cu (Cox and Singer, 1986; model 23)
Mineral deposit model number 23
Age of mineralization Cretaceous? The widespread deposition of copper in Triassic greenstone and limestone of the area is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic or Early Cretaceous (MacKevett and others, 1997). Copper-bearing minerals were deposited in the underlying Nikolai Greenstone at about 112 Ma (Silberman and others, 1980).

Production and reserves

Indication of production None

Additional comments

The locality is in the Wrangell-Saint Elias National Park and Preserve.

References