|Quadrangle map, 1:250,000-scale||BN|
|Quadrangle map, 1:63,360-scale||D-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Perry Creek is a southwest tributary to Pinnell River. Its mouth is about 5 miles upstream of the confluence of the Pinnell and Inmachuk Rivers. This location includes terrace gravels on both the north and south sides of Perry Creek overlooking Pinnell River. The terrace gravels are capped by basalt flows about 200 to 250 feet vertically above the Pinnell River. This is location 74 of Cobb (1972; MF 417; 1975; OFR 75-429).|
Geologic descriptionThis location includes terrace gravels on both the north and south sides of Perry Creek overlooking Pinnell River. The terrace gravels are capped by basalt flows about 200 to 250 feet vertically above the Pinnell River (Henshaw, 1910). One terrace sequence includes (bottom to top); 3 to 9 feet of gold-bearing gravel on schist bedrock, 20 feet of muck including wood fragments near the base (a 3 foot-diameter log is reported to have been encountered somewhere in the Perry Creek mine workings), 25 feet of basalt, an indeterminate thickness of nonauriferous gravel, and an indeterminate thickness of basalt (Hopkins, 1963, p. C32). Henshaw (1910) indicates that one terrace level is 52 feet higher than another in the area. The fine, bright gold here, some nuggets worth $0.15 at $20/ounce, was in quartz-rich gravel (Moffit, 1905). Most of the bedrock in the area is a metasedimentary schist and marble sequence of Lower Paleozoic age (Till and others, 1986). The basalt flows are part of the Pleistocene Imuruk Volcanics and the terrace gravels may be correlative with the Pliocene-Pleistocene Kougarok gravels (Hopkins, 1963).
|Geologic map unit||(-163.090690823123, 65.8183038642128)|
|Mineral deposit model||Placer Au-PGE (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||Late Tertiary to Pleistocene; the age of the Kougarok gravels (Hopkins, 1963).|
|Workings or exploration||These basalt-covered terrace gravels are old channels that required underground drift mining; the extent and nature of these workings are not known.|
|Indication of production||Yes; small|
Cobb, E.H., 1972, Metallic mineral resources map of the Bendeleben quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-417, 1 sheet, scale 1:250,000.
Cobb, E.H., 1975, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Bendeleben quadrangle, Alaska: U.S. Geological Survey Open-File Report 75-429, 123 p.
Hopkins, D.M., 1963, Geology of the Imuruk Lake area, Seward Peninsula, Alaska: U.S. Geological Survey Bulletin 1141-C, p. C1-C101.
Moffit, F.H., 1905, The Fairhaven gold placers, Seward Peninsula, Alaska: U.S. Geological Survey Bulletin 247, 85 p.
|Reporters||Travis L. Hudson (Applied Geology)|
|Last report date||3/15/1999|