Geologic description
Gouge zone containing quartz veins in early Paleocene and Late Cretaceous quartz diorite. The vein quartz is drusy and contains scattered unspecified sulfides and much iron oxide. The quartz vein is 1 is 4 inches thick in all three open cuts. In one cut the vein is separated from another 12 inch quartz vein by 18 inches of altered quartz diorite. The vein was reported to have given high assays in gold (Capps, 1915). The early Paleocene and Late Cretaceous quartz diorite is part of a pluton which is mostly biotite-hornblende tonalite with lesser biotite-hornblende quartz diorite. Wall-rock alteration within a few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954). |
| Geologic map unit |
(-149.172205966224, 61.829472435496) |
| Mineral deposit model |
Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a) |
| Mineral deposit model number |
36a |
| Age of mineralization |
Late Cretaceous or younger; veins cut early Paleocene and Late Cretaceous quartz diorite. |
| Alteration of deposit |
Wall-rock alteration within a few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954). Oxidation of sulfide minerals. |
