Unnamed Occurrence (ARDF - MH057; west of West Fork Maclaren River), Valdez Creek Mining District, Matanuska-Susitna Borough, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - MH057; west of West Fork Maclaren River)	- not defined -
Valdez Creek Mining District	Mining District
Matanuska-Susitna Borough	Borough
Alaska	State
USA	Country

Location: This occurrence is at an elevation of about 4,300 feet on the south side of an east-flowing tributary to the West Fork Maclaren River, in the SE1/4 NW1/4 section 33, T. 19 S., R. 5 E., Fairbanks Meridian. The occurrence corresponds to locality 11 in figure 4 of Cobb (1979 [OFR 79-238]) and to locality 16 in table 2 of Nokleberg and others (1991).
Geology: The rock at this occurrence is propylitized basalt and andesite of the Nikolai Greenstone of Late Triassic age (Nokleberg and others, 1982, 1991). Mineral deposits at the occurrences are quartz-epidote veins from 2 to 6 inches wide in a minor fault zone. The veins contain local concentrations of primary chalcocite, pyrrhotite, covellite (?), and secondary malachite (Smith and others, 1973, location B). Copper deposits hosted in the Nikolai Greenstone typically contain small amounts of silver.
Workings: Natural outcrops and float.
Age: Probably Cretaceous or early Tertiary (see MH060).
Alteration: Nikolai Greenstone is propylitized.

Commodities (Major) - Cu; (Minor) - Ag
Development Status: None
Deposit Model: Basaltic Cu (Cox and Singer, 1986, model 23).

Other Databases

Link to USGS - Alaska:	MH057

Other Regions, Features and Areas containing this locality

References