Upper Glacier

Prospect, Active?

Commodities and mineralogy

Main commodities Au; Co; Cu; Ni; Pd; Pt
Ore minerals chalcopyrite; magnetite; malachite; pentlandite; pyrite; pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-4
Latitude 63.3386
Longitude -145.6199
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Upper Glacier prospect is at an elevation of 4,150 feet on the southwest valley wall of lower Canwell Glacier. It is about 2.1 miles east-northeast of VABM 5422 'Canwell' near the center of section 22, T. 18 S., R. 11 E. The location is accurate.

Geologic setting

Geologic description

The Upper Glacier prospect is in the Triassic, Canwell mafic-ultramafic complex (Nokleberg and others, 1992 [MF]; 1992 [Open-File]]; Bittenbender and others, 2007). The complex is a sill-like body that trends west-northwest for about 3.5 miles, dips to the south at about 40 degrees, and is about 2,000 to 3,000 feet thick. It has a dunite core that grades outward to wehrlite, peridotite, and gabbro. The body was subsequently intruded by a Cretaceous quartz-diorite to granodiorite pluton.
The Upper Glacier prospect was found in 1995 by American Copper and Nickel Company (ACNC) working with Fort Knox Gold Resources Inc. (Bittenbender and others, 2007). ACNC flew an airborne geophysical survey over the prospect in 1997 (Burns and Clautice, 2003). Nevada Star Resources Corp. did a Max-Min electromagnetic survey in 2004 and drilled 5 holes in 2003(?) and 2004. The Bureau of Land Management examined and sampled the prospect in the early 2000s (Bittenbender and others, 2007).
The mineralization consists of disseminated pyrrhotite, pyrite, and traces of chalcopyrite and pentlandite in feldspathic peridotite near the base of the Canwell complex (W.T. Ellis, oral communication, 1998; Bittenbender and others, 2007). The peridotite is surrounded by dunite and it is cut by high-angle faults; the peridotite is copper-stained and is cut by magnetite seams as much as 1 inch thick. The mineralized rock extends north-northwest for about 200 feet and is about 75 feet thick. Bittenbender and others (2007) collected 5 samples. A chip sample across 21 feet of mineralized peridotite contained 35 parts per billion (ppb) gold, 102 ppb platinum, 132 ppb palladium, 798 parts per million (ppm) copper, and 3,140 ppm nickel. Their highest grade sample was from peridotite with 3-5 percent coarsely-crystalline, disseminated sulfides. It contained 144 ppb gold, 259 ppb platinum, 280 ppb palladium, 2,330 ppm copper, and 3,600 ppm nickel.
Geologic map unit (-145.622152000053, 63.3381894571087)
Mineral deposit model Nickel-copper-PGE mineralization in a differentiated mafic-ultramafic sill.
Age of mineralization Probably genetically related to the emplacement of a Triassic mafic-ultramafic complex.
Alteration of deposit Oxidation of copper minerals.

Production and reserves

Workings or exploration The Upper Glacier prospect was found in 1995 by American Copper and Nickel Company (ACNC) working with Fort Knox Gold Resources Inc. (Bittenbender and others, 2007). ACNC flew an airborne geophysical survey over the prospect in 1997 (Burns and others, 2003). Nevada Star Resources Corp. did a Max-Min electromagnetic survey in 2004 and drilled 5 holes in 2003(?) and 2004. The Bureau of Land Management examined and sampled the prospect in the early 2000s (Bittenbender and others, 2007).
Indication of production None
Reserve estimates None.
Production notes None.

References

References

Bittenbender, P.E., Bean, K.W., Kurtak, J.M., and Deininger, James Jr., 2007, Mineral assessment of the Delta River Mining District area, east-central, Alaska: U.S. Bureau of Land Management, Alaska Technical Report 57, 675 p.
Reporters W.T. Ellis (Alaska Earth Sciences), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS); D.J. Grybeck (Contractor, USGS)
Last report date 5/13/2012