Unnamed (east of Billy Hawk Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Cu; Pb
Ore minerals argentiferous galena; chalcopyrite; malachite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale SH
Quadrangle map, 1:63,360-scale B-4
Latitude 66.25
Longitude -157.51
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 2,500 feet on an east-trending ridge, about 1.5 mile east of Billy Hawk Creek. The map site is in section 24, T. 10 N., R. 6 E., of the Kateel River Meridian. Cobb (1972, MF-448), locations 3 and 4.

Geologic setting

Geologic description

Bedrock in the area of this occurrence consists of andesitic volcanic rocks of Late Jurassic-Early Cretaceous age, and quartz latite volcanic rocks of Late Cretaceous age, both of which are intruded by the Late Cretaceous Hawk River quartz monzonite. The older andesitic volcanics are thermally metamorphosed in the vicinity of the Hawk River pluton. Numerous fine-grained, pyritiferous, felsic dikes cut both the andesitic and quartz latite volcanics throughout this area. Pyrite-bearing, milky-white, vuggy, quartz veins cut the volcanics in a northwest-trending belt about 6.5 miles long by 1.5 mile wide. This belt parallels a zone of prominent, northwest-trending lineations and faults. The veins are narrow, appear to strike NE and dip steeply to the north. Locally they contain irregular segregations of argentiferous galena along with lesser chalcopyrite and malachite. Pyrite occurs in cubes up to one inch on a side and is almost completely oxidized to limonite. The galena is fresh and fills vugs and fissures along the edges of the veins. No galena or chalcopyrite were found in the volcanics, although the andesitic wallrock locally contains abundant pyrite. Grab samples contained up to 200 ppm Ag, 0.3 ppm Au, 3,000 ppm Cu, 20,000 ppm Pb, and 1,500 ppm Zn (Miller and Ferrians, 1968).
Geologic map unit (-157.512670176437, 66.2494161439947)
Mineral deposit model Polymetallic veins (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c
Age of mineralization Late Cretaceous or younger.
Alteration of deposit Pyrite is almost completely oxidized to limonite.

Production and reserves

Workings or exploration The area was mapped by Miller and others (1966). Six rock samples and sixteen stream sediment samples were collected and analyzed by Miller and Ferrians (1968) during their field investigations. One hundred and fifty lode claims were staked in 1972 (Grybeck, 1977).
Indication of production None

References