Equator Prospects and Saco Prospects, Prince of Wales Island, Ketchikan Mining District, Prince of Wales-Hyder Census Area, Alaska, USAi

Regional Level Types
Equator Prospects and Saco Prospects	Group of Prospects
Prince of Wales Island	Island
Ketchikan Mining District	Mining District
Prince of Wales-Hyder Census Area	Census Area
Alaska	State
USA	Country

Location: The Equator and Saco prospects are adjacent to each other. The adit at the Equator prospect is at an elevation of about 350 feet, the Saco adit is at an elevation of about 200 feet. The prospects are about 2.1 miles east of the north end of Hump Island, near the southeast corner of section 32, T 76 S., R. 88 E.

Geology: As described by Wright and Wright (1908), the main working on the Equator prospect is a 50-foot adit at an elevation of about 350 feet. The deposit consists of a quartz vein enclosing masses of limestone country rock. The vein strikes 60NW and dips 50SW, parallel to the strike of the host rocks, but with a slightly different dip. The vein contains chalcopyrite and pyrite, with gold values. On the Saco prospect, a 50-foot adit is at an elevation of about 200 feet. A vein that strikes east-west varies from 4 feet thick at the portal to 2 inches thick at the face. The host rock is talc schist that strikes north and dips vertically. The rocks in the area are part of the Wales Group of Late Proterozoic and Cambrian age (Eberlein and others, 1983; Brew, 1996). Maas and others (1992) collected a 4-inch[?] chip sample across the vein in the Saco adit that contained 1,441 parts per million (ppm) copper, 0.6 ppm silver, and less than 5 parts per billion (ppb) gold. Hedderly-Smith (1999 [Inventory]) collected a representative sample of the dump of the Saco adit that contained 2.4 percent copper, 0.7 ppm silver, and 4 ppb gold. Maas and others (1991,1992) and Hedderly-Smith (1999 [Inventory]) consider the deposit at the Equator prospect to be a mineralized breccia similar to the copper-gold deposits along the Kael-7 Mile Trend (CR188); the deposit at the adjacent Saco prospect is probably an epigenetic quartz vein.

Workings: The Equator and Saco prospects were explored by 50-foot adits prior to 1908 and were sampled by government and industry geologists in the 1990's.

Age: Younger than the Late Proterozoic or Cambrian country rock.

Alteration: The mineralized fault zone at the Equator prospect is probably similar to the breccia deposits in the Kael-7 Mile Trend (CR188). If so, it is probably marked by silicification and dolomitization of the rock fragments in the breccia and of the country rock.

Commodities (Major) - Au, Cu

Development Status: None

Deposit Model: The Equator prospect is probably a stratiform Au-Cu breccia zone in marble.

Other Databases

Link to USGS - Alaska:	CR184

Other Regions, Features and Areas containing this locality

References