Geologic descriptionThis occurrence is in Nikolai Greenstone of Late Triassic age (Nokleberg and others, 1991), which was mapped as Boulder Creek volcanics by Stout (1976). The deposit consists of quartz-epidote-calcite veins that contain pyrite, chalcopyrite, bornite, and secondary azurite and malachite. The veins range from less than an inch to about 1 foot thick and occupy steep north- to northeast-trending faults and joints that cut and are not deformed by the Amphitheater syncline (Stout, 1976). The deposit was not sampled; silver is typically present in the copper deposits of the Nikolai Greenstone. |
| Geologic map unit |
(-146.216052276613, 63.1755730079151) |
| Mineral deposit model |
Basaltic Cu (Cox and Singer, 1986; model 23). |
| Mineral deposit model number |
23 |
| Age of mineralization |
The quartz veins are localized in north-northeast-trending faults and joints that cut across the folded limbs of the Amphitheater syncline. They postdate the folding, which is of Jurassic age, and are probably either Cretaceous, related to regional metamorphism and granitic plutonism (Nokleberg and others, 1986; Kurtak and others, 1992), or early Tertiary (Stout, 1976). |
