Little Caribou

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu; Sb; Zn
Other commodities Ag; Au; Mo
Ore minerals chalcopyrite; hematite; magnetite; pyrite; sphalerite; stibnite
Gangue minerals epidote; tourmaline

Geographic location

Quadrangle map, 1:250,000-scale MM
Quadrangle map, 1:63,360-scale D-1
Latitude 63.7714
Longitude -150.4994
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Little Caribou occurrence (Cobb, 1980 [OFR 80-363]) is at an elevation of about 2900 feet on a ridge about 1/2 mile north of Little Caribou Creek . The location is about on the boundary between the Mt. McKinley D-1 and D-2 quadrangles. It is accurate within 500 feet. The Little Caribou site correponds to location 69 of Bundtzen, Smith, and Tosdal (1976), D of Hawley and Associates (1978), 77a of Bundtzen (1981), and 29 of MacKevett and Holloway (1977).

Geologic setting

Geologic description

The Little Caribou occurrence is a skarn deposit in a relatively thin marble layer in contact with mica schist of the Birch Creek Schist. No nearby intrusive is known. The skarn is 3 to 5 feet thick and can be followed for about 500 feet. It consists of epidote and magnetite, accompanied by small amounts of pyrite, chalcopyrite, stibnite, and sphalerite; tourmaline occurs locally. Samples of the skarn assay 0.01-0.03 ounce of gold per ton, 0.01 to 0.17 ounce of silver per ton, up to 0.37 percent zinc, and a little copper and lead (Bundtzen, 1981). Stibnite, in float mainly composed of graphitic schist and marble, occurs near the skarn.
Hawley and Associates (1978, fig. and table 4.1-A(2) conducted a soil survey east of the skarn outcrop. The total of Cu+Pb+Zn in soil generally is less than 700 ppm, but one sample contained more than 3500 ppm combined metals, and one contained more than 700 ppm antimony. Stream-sediment samples collected from small creeks that drain the area northwest of the skarn deposit were relatively rich in zinc.
Geologic map unit (-150.501704227306, 63.7709053003076)
Mineral deposit model Pb-Zn? skarn deposit (Cox and Singer, 1986; model 18c?).
Mineral deposit model number 18c?
Age of mineralization Uncertain; possibly Eocene (see record MM091).
Alteration of deposit Replacement of marble by epidote-magnetite(-tourmaline) skarn.

Production and reserves

Workings or exploration The area has been mapped and soil sampled but not otherwise explored.
Indication of production None

Additional comments

The occurrence is in Denali National Park and Preserve.

References