Unnamed Occurrence (ARDF - LH019; head of South Fork Kuskokwim River), McGrath Mining District, Bethel Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - LH019; head of South Fork Kuskokwim River)	- not defined -
McGrath Mining District	Mining District
Bethel Census Area	Census Area
Alaska	State
USA	Country

Location: This occurrence is at an elevation of about 6,200 feet on a ridge along the east side of the southeast headwater tributary of South Fork Kuskokwim River. The map site is 0.4 mile south-southwest of peak 6980, in the northeast corner of section 17, T 17 N, R 22 W, of the Seward Meridian. This is locality Cobb (1972 [MF 412]; 1976 [OF 76-485]). The location is probably accurate to within a quarter of a mile.
Geology: Reed and Elliott (1970) reported that sparse fractures as much as 1 cm wide in quartz monzonite are filled with quartz, chalcopyrite, pyrite, and traces of other sulfide minerals. Pyrite and chalcopyrite are also disseminated in the quartz monzonite. A sample of a vein contained greater than 20,000 ppm copper, 100 ppm silver, and anomalous lead. The mineralized quartz monzonite is Tertiary; it intrudes upper Mesozoic slate and graywacke as well as older, probably Cretaceous, granitic rocks (Cobb and Reed, 1981).
Workings: Reconnaissance sampling has been completed in this area (Reed and Elliott, 1970).
Age: Tertiary. Quartz veins and mineralization crosscut Tertiary intrusive rocks.
Alteration: Quartz veining.

Commodities (Major) - Ag, Cu
Development Status: None
Deposit Model: Polymetallic veins (Cox and Singer, 1986, models 22c)

Other Databases

Link to USGS - Alaska:	LH019

Other Regions, Features and Areas containing this locality

References