|Quadrangle map, 1:250,000-scale||DN|
|Quadrangle map, 1:63,360-scale||C-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||
The Arkansas prospect (Cobb, 1980 [OFR 80-363]) is at an elevation of about 3450 feet on a minor east-trending ridge at the head of the West Fork of Glen Creek. It is in the SE 1/4 NE 1/4 section 2, T. 16 S., R. 17 W., Fairbanks Meridian. The location is probably accurate within 500 feet. The Arkansas prospect is 1500 feet downstream from the Pension (DN081) prospect (Davis, 1923).The Arkansas and Pension prospects are included in location 19 of Cobb (1972 [MF 366]). The Arkansas prospect is number 226 of Hawley and Associates (1978), 55 of Bundtzen (1981), and 69 of Thornsberry, McKee, and Salisbury (1984).
The country rocks at the Arkansas prospect are metafelsite and greenschist (meta-andesite) of the lower Paleozoic Spruce Creek sequence; they are cut by a plug or dike of Tertiary basalt (Bundtzen, 1981). The prospect is in a half-mile-long fault block terminated on the east by a northwest-striking cross fault exposed along the West Fork of Glen Creek (Thornsberry, McKee, and Salisbury, 1984, fig. K-2).The deposit consists of a 14-foot-thick shear zone containing quartz-sulfide veins. Individual veins are as much as 5 feet thick, and are separated by zones of sheared schist. The quartz contains galena, stibnite, and some sphalerite; a grab sample from a 5-foot-thick segment assayed 90 ounces of silver per ton (Davis, 1923). The principal vein is 1 to 4 feet thick, is vertical, and strikes N 70 E (Bundtzen, 1981). It contains arsenopyrite, extensively replaced by scorodite, and galena, boulangerite, jamesonite, and stibnite. A sample collected at the site in 1983 assayed a trace of gold, 2.33 ounces of silver per ton, 3.55 percent lead, 0.50 percent zinc, 1.9 percent antimony, and 5.65 percent arsenic (Thornsberry, McKee, and Salisbury, 1984, v. 2, occurrence 69).
|Geologic map unit||(, )|
|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 DN091).|
|Alteration of deposit||Oxidation of arsenic mineral.|
|Workings or exploration||The Arkansas vein was discovered in 1921(Davis, 1923). The prospect was mapped by Bundtzen (1981); an adit at the site was caved.|
|Indication of production||Undetermined|
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.
Cobb, E. H., 1972, Metallic mineral resources map of the Mount McKinley quadrangle, Alaska: U. S. Geological Survey Miscellaneous Field Studies Map MF-366, 1 sheet, scale 1:250,000.
Cobb, E.H., 1980, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mount McKinley quadrangle, Alaska: U. S. Geological Survey Open-File Report 80-363, 150 p.
Cox, D.P., and Singer, D.A., eds., 1986, Mineral deposit models: U.S. Geological Survey Bulletin 1693, 379 p.
Davis, J. A., 1923, The Kantishna region, Alaska, in Stewart, B. D., Annual Report of the Mine Inspector to the Governor of Alaska, 1922: Alaska Division of Geological and Geophysical Surveys AR-1922.
Hawley, C. C. and Associates, Inc, 1978, Mineral appraisal of lands adjacent to Mt. McKinley National Park, Alaska: U. S. Bureau of Mines Open-File Report 24-78, 275 p. (paged by sections).
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||5/2/2001|