|Quadrangle map, 1:250,000-scale||MM|
|Quadrangle map, 1:63,360-scale||C-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Pittsburgh prospect (Cobb, 1980 [OFR 80-363]) is at an elevation of about 2700 feet near the head of a south-facing gulch east of Iron Gulch. It is about 0.3 mile north of the center of section 7, T. 16 S., R. 17 W., Fairbanks Meridian. The location is accurate within about 500 feet. The prospect is included in occurrence 41 of Thornsberry, McKee, and Salisbury (1984).|
The area of the Pittsburgh prospect is underlain by schistose metafelsite of the Spruce Creek sequence (Bundtzen, 1981; Thornsberry, McKee, and Salisbury, 1984, fig. K-2; v. 2, occurrence 41). The deposit consists mainly of a mineralized quartz-calcite vein that probably is the continuation of the Pennsylvania vein (MM116). According to Davis (1923, p. 129): 'Although there is a gap of about 1000 feet... it is quite likely that this vein [Pennsylvania] is the same one that is exposed on the discovery cut of the Pittsburgh claim. The vein matter is quartz containing some pyrite and calcite, and free gold can be panned from samples taken along the outcrop.' When visited by Davis, the discovery cut on the Pittsburgh vein was partly sloughed, but vein material was still visible. He reported a 6- to 7-foot-thick quartz-calcite vein containing sulfides.Apparently, little work has been on the Pittsburgh claim since its discovery. A rock sample collected close to the west end line of the claim contained 1050 ppm lead and 4 ppm silver (Hawley and Associates, 1978, sample 147). Thornsberry, McKee, and Salisbury (1984, v. 2) found several sloughed pits and fairly abundant quartz float on the claim.
|Geologic map unit||(-150.920286264714, 63.5459943909179)|
|Mineral deposit model||Low-sulfide gold-quartz vein (Cox and Singer, 1986; model 36a).|
|Mineral deposit model number||36c|
|Age of mineralization||The deposit is assumed to be Eocene (see record MM091).|
|Workings or exploration||The property was developed by pits and shallow shafts in 1922 or earlier. The claim has been inactive for many years.|
|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., 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||4/28/2001|