|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||This unnamed occurrence is an elevation of about 1300 feet on the south side of the canyon of Glacier Creek, about 0.25 mile northwest of Eighteen Gulch. The occurrence corresponds to number 46 of Thornsberry, McKee, and Salisbury (1984). The location is probably accurate within 0.3 mile.|
Geologic descriptionThis occurrence consists of sulfide and alteration minerals in sheared and altered metafelsite of the lower Paleozoic Spruce Creek sequence (Bundtzen, 1981; Thornsberry, McKee, and Salisbury, 1984, v. 2, occurrence 46). Some vein quartz is present. Exposures are poor, but the mineralized felsite appears to trend northwesterly. Pyrite, the most abundant unoxidized metallic mineral, is disseminated in the metafelsite. Arsenopyrite may also be present, as suggested by a sample that contained 0.285 percent arsenic. Assays showed no precious metals or valuable base metals. The pyrite is extensively oxidized to limonite, chiefly goethite, and to jarosite. Iron oxides also stain the soil near the occurrence (Thornsberry, McKee, and Salisbury, 1984, v. 2, occurrence 46). The nature of the occurrence is uncertain; it appears to be weakly mineralized metafelsite possibly similar to that at occurreences MM018 and MM022.
|Geologic map unit||(-150.918290763669, 63.5840945803806)|
|Mineral deposit model||Volcanogenic?|
|Age of mineralization||Pyrite may have been an original volcanogenic(?) component of the lower Paleozoic Spruce Creek felsite (Bundtzen, 1981). The quartz veins may represent later epigenetic mineralization (see record MM091).|
|Alteration of deposit||Iron-oxide alteration.|
|Workings or exploration||The site is a poorly exposed natural outcrop.|
|Indication of production||None|
Additional commentsThe occurrence 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.
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||4/29/2001|