BM-75 Occurrence, Delta River Mining District, Southeast Fairbanks Census Area, Alaska, USAi

Regional Level Types
BM-75 Occurrence	Occurrence
Delta River Mining District	Mining District
Southeast Fairbanks Census Area	Census Area
Alaska	State
USA	Country

Location: The BM-75 occurrence is at an elevation of about 4,300 feet in the headwaters of a north-flowing tributary of upper Eureka Creek and is in the SE1/4SE1/4 section 21, T. 19 S., R. 8 E., Fairbanks Meridian.
Geology: The BM-75 occurrence is hosted by the Fish Lake mafic-ultramafic intrusive complex, which is of Late Triassic age and believed to be a lopolithic feeder of the Nikolai basalt flows (Nokleberg and others, 1991). The occurrence is in a pod of serpentinized peridotite in a gabbroic unit of the third magmatic cycle of the Fish Lake complex. The pod of serpentinized peridotite contains a few percent disseminated pyrrhotite, chalcopyrite, pentlandite, and magnetite (Foley, 1992; Foley and others, 1989) A grab sample contained 70 parts per billion (ppb) palladium and 70 ppb platinum (U.S. Bureau of Mines, unpublished data, 1985).
Workings: The occurrence is on active Fort Knox Gold Resource claims.
Age: Late Triassic, the age of the host rock.
Alteration: The peridotite is serpentinized.

Commodities (Major) - Cu, Ni, Pd, Pt
Development Status: None
Deposit Model: Ni-Cu-PGE in differentiated mafic-ultramafic sill.

Other Databases

Link to USGS - Alaska:	MH171

Other Regions, Features and Areas containing this locality

References