Unnamed (between Crooked Creek and Little Caribou Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Zn
Other commodities Ag; Au; Cu; Pb
Ore minerals pyrite; sphalerite

Geographic location

Quadrangle map, 1:250,000-scale MM
Quadrangle map, 1:63,360-scale D-1
Latitude 63.8026
Longitude -150.422
Nearby scientific data Find additional scientific data near this location
Location and accuracy This site represents two geologically similar occurences that are about 0.2 mile apart. The western occurrence is at an elevation of about 2250 feet; the eastern occurrence is at an elevation of about 2400 feet. For this record, the location is at an elevation of 2200 feet, about 0.4 mile east of the center of section 10, T. 13 S., R. 15 W., Fairbanks Meridian. The site corresponds to the location of sample numbers 67 and 71 of Hawley and Associates (1978).

Geologic setting

Geologic description

This record describes two occurrences of sulfide-bearing schist, about 0.2 mile apart, in siliceous units of the Devonian or Mississippian Keevy Peak Formation (Bundtzen, 1981). In the area of the occurrences, the strata strike NE, and dip steeply (Hawley and Associates, 1978, fig. 4.1-A(2)). The occurrence at Hawley and Associates' location 67 consists of weakly pyritic siliceous schist. In addition to pyrite, the schist probably contains sphalerite and small amounts of other sulfide minerals. A sample assayed 0.1 ppm gold, 2.4 ppm silver, 215 ppm copper, 95 ppm lead, and 1000 ppm zinc. Hawley and Associates' location 71 is in sulfide-bearing metachert. A sample assayed 4.0 ppm silver, 315 ppm copper, 20 ppm lead, and 520 ppm zinc. The occurrences are stratabound, and may be Devonian or Mississippian, the depositional age of the Keevy Peak Formation.
Geologic map unit (-150.424307465168, 63.8021077106723)
Mineral deposit model Stratabound; syngenetic; possibly volcanogenic.
Age of mineralization Probably Devonian or Mississippian, the protolith age of the Keevy Peak Formation.
Alteration of deposit Sulfidization of schist and metachert hostrocks.

Production and reserves

Workings or exploration The occurrences were sampled during reconnaissance mapping of the area (Hawley and Associates, 1978). There are no workings.
Indication of production None

Additional comments

The site is in Denali National Park and Preserve.

References

References

Bundtzen, T. K., 1981, Geology and mineral deposits of the Kantishna Hills, Mt. McKinley quadrangle, Alaska: M. S. Thesis, University of Alaska, College, Alaska, 238 p.
Reporters C.C. Hawley
Last report date 5/8/2001