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. |