Geologic descriptionThe early descriptions of a residual gold placer on schist bedrock is believed to be at this location. This residual placer contains angular, spongy, and bright gold in 4 to 7 feet of angular schist and quartz and adjacent weathered schist bedrock (Collier and others, 1908). Small amounts of cinnabar, cerussite, and pyromorphite are present in placer concentrate from Wonder Gulch (Anderson, 1947). Sainsbury and others (1969) indicate that an attempt to mine an auriferous quartz ledge here was unsuccessful. Large iron-stained quartz boulders are present in the upper part of the placer on Wonder Gulch (Sainsbury and others, 1969). Bedrock here is part of a low grade Lower Paleozoic metasedimentary assemblage (Till and others, 1986). |
Geologic map unit |
(-164.734661831276, 65.3142625010183) |
Mineral deposit model |
Gold-bearing quartz veins and schist. |
Age of mineralization |
Possibly mid-Cretaceous; this is the age of some lode gold deposits on southern Seward Peninsula. The southern Seward Peninsula lode gold deposits formed as a result of mid-Cretaceous metamorphism (Apodoca, 1994; Ford, 1993, Ford and Snee, 1996; Goldfarb and others, 1997) that accompanied regional extension (Miller and Hudson, 1991) and crustal melting (Hudson, 1994). This higher temperature metamorphism was superimposed on high pressure/low temperature metamorphic rocks of the region. |