West Fork

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Ag; Au
Ore minerals unspecified copper minerals

Geographic location

Quadrangle map, 1:250,000-scale CH
Quadrangle map, 1:63,360-scale A-4
Latitude 67.2
Longitude -148.73
Nearby scientific data Find additional scientific data near this location
Location and accuracy The West Fork occurrence is at an elevation of about 1,700 ft on the north side of the West Fork Chandalar River approximately 6 miles west of its confluence with the North Fork Chandalar River (NW1/4 sec. 6, T. 27 N., R. 5 W., of the Fairbanks Meridian ). The location is accurate within a 1/2-mile radius.

Geologic setting

Geologic description

Occurrence is described only as Cu minerals in Devonian(?) volcanic rocks (DeYoung, 1978). An analysis of a rock sample collected by Brosgé and Reiser (1972) from this location showed 0.04 to 0.79 ppm Au and 1.0 to 3.0 ppm Ag. The occurrence also coincides with a location noted as an occurrence of metallic minerals (Cu) by Brosgé and Reiser (1964). No other data on the mineralization is available. The host rock unit is described as pyroxene andesite flows and pyroxene diorite intrusives, hornblende andesite pyroclastics, and some diabase and gabbro.
Geologic map unit (-148.732702168297, 67.1995954751987)

Production and reserves

Indication of production None

Additional comments

The rock sample described by Brosgé and Reiser (1972) that contained 1 to 3 ppm Ag and 0.04 to 0.079 ppm Au appears to be from the general area of the West Fork prospect. The occurrence also probably coincides with the location noted as an occurrence of metallic minerals (Cu) plotted by Brosgé and Reiser (1964) along the lower West Fork Chandalar River.