|Quadrangle map, 1:250,000-scale||HG|
|Quadrangle map, 1:63,360-scale||D-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is on the south side of an east-west oriented mountain between the Kinegnak River and the headwaters of the Unaluk River. It is at an elevation of about 750 feet on the north side of a saddle, in the E1/2 of section 9, T 15 S, R 73 W, of the Seward Meridian. It is probably located to within about 1/3 mile. It is locality 2 of Cobb (1972 [MF 362]; 1980 [OF 80-909]).|
Geologic descriptionOn June 1, 1972, Allen L. Clark (U.S.G.S.) told E. H. Cobb that lode gold had been found at this location (Cobb, 1980, p. 33 [OF 80-909]). Cobb (1972 [MF 362]) showed this location to be on the the south side of an east-west oriented mountain between the Kinegnak River and the headwaters of the Unaluk River. It is at an elevation of about 750 feet on the north side of a saddle marking the approximate south contact of a mafic pluton and sedimentary rocks (Hoare and Coonrad, 1979). The mafic plutons in the general area are gabbroic rocks that locally contain olivine and show compositional layering. They have yielded Jurassic K/Ar ages that range from 159 to 187 Ma (Hoare and Coonrad, 1978). The country rocks intruded by the pluton are Paleozoic to Mesozoic sedimentary rocks that include limestone near the contact just to the west of this locality. Fechner (1988) mapped and sampled the general area. A pan-concentrate sample from a saddle within the pluton contained 240 ppb Au and 125 ppb Pt; a chert sample from the contact zone at this location contained 70 ppb Au; and three small flakes of gold were recovered from a 0.1-cubic-yard sample of alluvium from a creek draining the east side of the pluton.
|Geologic map unit||(-161.454218654381, 58.8912181385485)|
|Age of mineralization||If the mineralization is epigenetic, then it is probably Early Jurassic or younger. It can be as old as the nearby pluton, which is correlated with nearby mafic plutons that have been K/Ar dated as Jurassic in age (Hoare and Coonrad, 1978).|
|Workings or exploration||No workings have been reported at this occurrence.|
|Indication of production||None|
Cobb, E.H., 1972, Metallic mineral resources map of the Hagemeister Island quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-362, 1 sheet, scale 1:250,000.
Cobb, E.H., 1980, Summaries of data and lists of references to metallic and selected nonmetallic mineral deposits in fifteen quadrangles in southwestern and west-central Alaska: U.S. Geological Survey Open-File Report 80-909, 103 p.
Fechner, S.A., 1988, Bureau of Mines mineral investigation of the Goodnews Bay mining district, Alaska: U.S. Bureau of Mines Open-File Report 1-88, 230 p., 3 sheets.
|Reporters||Travis L. Hudson|
|Last report date||3/18/2001|