|Quadrangle map, 1:250,000-scale||MM|
|Quadrangle map, 1:63,360-scale||C-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is at an elevation of about 2680 feet on a southeast-trending ridge about midway between Brooker Mountain and Alpha Ridge. It is approximately on the boundary between sections 21 and 22, T. 16 S., R. 18 W., Fairbanks Meridian. The location is probably accurate within 300 feet. The prospect is number 5 of Thornsberry, McKee, and Salisbury (1984).|
This prospect is in a high-angle(?) fault in the the hanging wall of a probable low-angle fault that places Birch Creek Schist above Spruce Creek rocks in the upper Eldorado Creek area (Thornsberry, McKee, and Salisbury, 1984, pl. K-6). The high-angle fault strikes NNE. The deposit is in quartz-mica and feldspar-quartz-mica schist of the Birch Creek Schist (Bundtzen, 1981).The deposit consists of oxidized, polymetallic veins. Gossan in shallow, caved pits locally is coated with malachite. Sulfide-bearing gossan in one pit contains tetrahedrite. The presence of galena or its oxidation product cerussite, and of sphalerite or an oxidation product such as smithsonite, is inferred from analyses of the tetrahedrite-bearing sample, which assayed 5.16 ounces of silver per ton, 1.25 percent copper, 4.45 percent lead, 33 percent zinc, and 2.45 percent antimony. Another sample of gossan assayed 7.2 ounces of silver per ton and 2.95 percent zinc (Thornsberry, McKee, and Salisbury, 1984, v. 2, occurrence number 5).
|Geologic map unit||(-151.034584721194, 63.508491169707)|
|Mineral deposit model||Polymetallic vein (Cox and Singer, 1986; model 22c).|
|Mineral deposit model number||22c|
|Age of mineralization||The deposit is assumed to be Eocene (see record MM091).|
|Alteration of deposit||Oxidation of sulfide minerals.|
|Workings or exploration||The prospect was explored by four hand-dug pits of unknown date.|
|Indication of production||None|
Additional commentsThe prospect is in Denali National Park and Preserve.
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.
Cox, D.P., and Singer, D.A., eds., 1986, Mineral deposit models: U.S. Geological Survey Bulletin 1693, 379 p.
Thornsberry, V. V., McKee, C. J., and Salisbury, W. G., eds, 1984, 1983 Mineral Resource Studies: Kantishna Hills and Dunkle Mine Areas, Denali National Park and Preserve, Alaska: U. S. Bureau of Mines Open-File Report 129-84. 3 Volumes: v. 1, Text; v. 2, Appendices; v. 3, Maps. Prepared by Salisbury & Dietz, Inc., Spokane, WA.
|Last report date||4/18/2001|