Unnamed (ridge between middle and east forks in Broxson Gulch)

Occurrence, Active

Commodities and mineralogy

Main commodities Ni
Other commodities Ag; Au
Ore minerals pyrite; pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-5
Latitude 63.3488
Longitude -146.067
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of 5,350 feet on the ridge between the locally named middle fork and the east fork of the stream(s) in Broxson Gulch (see figure 2 of Rose, 1965). The occurrence is in the SE1/4SW1/4 section 17, T. 18 S., R. 9 E., Fairbanks Meridian; it corresponds to locality 48 in table 2 of Nokleberg and others (1991).

Geologic setting

Geologic description

The rock at this occurrence is Upper Triassic gabbro and peridotite that intrudes Upper Triassic metabasalt (Nokleberg and others, 1991). The gabbro forms a sill-like body more than 1,000 feet long and 10 feet thick. It is sheared and highly iron stained and contains disseminated pyrite and possibly pyrrhotite. Grab sample 79NK008A of mineralized gabbro assayed 0.15 percent nickel, 3 parts per million (ppm) silver, and 0.10 ppm gold (Nokleberg and others, 1991, locality 48, table 2).
Geologic map unit (-146.069265808922, 63.3483812786012)
Mineral deposit model Ni-Cu-PGE in differentiated mafic-ultramafic sill.
Age of mineralization Late Triassic, the age of the host rock.
Alteration of deposit Pyritization and iron staining of host rock.

Production and reserves

Workings or exploration The occurrence is on active MAN Resources claims.
Indication of production None