Unnamed (in Tatlawiksuk River basin)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag
Other commodities Cu
Ore minerals pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale MG
Quadrangle map, 1:63,360-scale A-6
Latitude 62.233
Longitude -155.592
Nearby scientific data Find additional scientific data near this location
Location and accuracy This unnamed occurrence is located in a small saddle along a southwest-northeast-trending spur overlooking a south-flowing tributary of the Tatlawiksuk River; it is at an elevation of 2,150 feet (655 m) in the NW1/4 sec. 28, T. 25 N., R. 34 W., of the Seward Meridian. The reporter visited the site in 1978; at station no. 78BT196.

Geologic setting

Geologic description

This unnamed occurrence is a pyrite-rich quartz-breccia zone within a N5E-trending, high-angle fault zone that juxtaposes quartz monzonite and thermally altered Kuskokwim Group rocks (Wilson and others, 1998). A pronounced fault zone is at least 15 meters thick and extends for 10 kilometers along strike. One grab sample of pyrite-rich gossan from the fault zone contained 10.1 grams/tonne silver and 142 ppm copper (T.K. Bundtzen, written communication, 1998).
Geologic map unit (-155.594330548531, 62.232345654464)
Mineral deposit model Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c

Production and reserves

Workings or exploration The unnamed occurrence was found by the reporter during geologic mapping conducted for the Alaska Division of Geological and Geophysical Surveys; and eventually published in Wilson and others (1998). One grab sample contained 10.1 grams/tonne silver and 142 ppm copper (T.K. Bundtzen, written communication, 1998).
Indication of production None
Reserve estimates None.

References