Jack Bay #2

Prospect, Inactive

Commodities and mineralogy

Main commodities Au; Cu
Ore minerals chalcopyrite; pyrrhotite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale CV
Quadrangle map, 1:63,360-scale D-7
Latitude 60.985
Longitude -146.43
Nearby scientific data Find additional scientific data near this location
Location and accuracy The site is at an elevation of 150 feet in a river valley southeast of Jack Bay, and about 2 miles upstream from the head of the bay. It is in the SW1/4 sec. 23, T. 10 S., R. 7 W., of the Copper River Meridian. The location is accurate to within 1000 ft. This prospect is shown as C-96 in Jansons and others (1984).

Geologic setting

Geologic description

The area of this prospect is underlain by Upper Cretaceous Valdez Group metasedimentary rocks (Nelson and others, 1985). A well-defined, 6-inch- wide, quartz vein in slate contains chalcopyrite and pyrrhotite . One grab sample contained 140 ppm Cu and 0.006 oz. Au/ton (Jansons and others, 1984).
Gold mineralization in veins cutting the rocks of the Valdez Group is interpreted by Goldfarb and others (1992) to be the result of Tertiary metamorphism.
Geologic map unit (-146.43200554377, 60.9844688844623)
Mineral deposit model Chugach-type low-sulfide Au-quartz veins (Bliss, 1992; model 36a.1; Goldfarb and others, 1986).
Mineral deposit model number 36a.1
Age of mineralization Tertiary based on the age of the mineralizing event (Goldfarb and others, 1992).

Production and reserves

Indication of production None

References