Unnamed Occurrence (ARDF - LH017; head of Hartman River), McGrath Mining District, Bethel Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - LH017; head of Hartman River)	- not defined -
McGrath Mining District	Mining District
Bethel Census Area	Census Area
Alaska	State
USA	Country

Location: This occurrence is in the peaks at the head of the southeast headwaters of the Hartman River. It is at an elevation of about 5,100 feet and 1.2 miles northwest of peak 5875. The map site is in the NE1/4 section 2, T 17 N, R 24 W, of the Seward Meridian. This is locality 6 of 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 finding mineralized float boulders at this locality. The boulders include argillite cut by 6-inch-wide quartz veins containing arsenopyrite, pyrite, tourmaline, and chalcopyrite, as well as quartz porphyry cut by thin veinlets containing pyrite and sphalerite. Cobb and Reed (1981) reported that upper Mesozoic graywacke, shale, and argillite are cut by mineralized shear zones and faults that contain disseminated sulfides, narrow veins of massive sulfide minerals, and quartz veins with minor amounts of sulfide minerals. In addition to copper and zinc anomalies, samples contain as much as 70 ppm silver and 0.9 ppm gold. This mineralized area is about one mile from a small Tertiary granitic stock.
Workings: Reconnaissance sampling has been completed in this area (Reed and Elliott, 1970).
Age: Tertiary? Mineralization crosscuts Upper Mesozoic sedimentary rocks. Polymetallic mineralization in this region is commonly associated with Tertiary granitic rocks.
Alteration: Quartz and tourmaline veining.

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

Other Databases

Link to USGS - Alaska:	LH017

Other Regions, Features and Areas containing this locality

References