| Basis for focus area |
Cluster of tungsten-bearing prospects; porphyry-related, breccias, propylitic alteration; includes Glacier Peak porphyry copper deposit. |
| Identified resources |
Indicated resources and past production of copper, molybdenum, silver, and tungsten. |
| Production |
Red Mountain (1930-1940): 15,000 tons ore. |
| Status |
Past mining and exploration. |
| Estimated resources |
Glacier Peak prospect: 50 to 100 million tons of ore with minimum grades of 0.027% W, 0.025% Mo, 0.45% Cu, 11.32 g/mt Ag, and 0.68 g/mt Au. Red Mountain resources (in 1983): 3.8 Mt at 1.32 Cu, 20.57 g/t Ag. |
| Geologic maps |
Cater and Crowder (1967), scale 1:62,500; Washington Division of Geology and Earth Resources (2016), scale 1:100,000. |
| Geophysical data |
Inadequate aeromagnetic and aeroradiometric coverage. |
| Favorable rocks and structures |
Jurassic metasedimentary and metavolcanic rocks intruded by an Oligocene granodiorite batholith, deposits seemingly following a N-S structural trend. |
| Deposits |
Glacier Peak (MRDS dep_id: 10008495), Red Mountain (MRDS dep_id: 10008893), Keefer Brothers (MRDS dep_id: 10107740), Esmeralda (MRDS dep_id: 10048447). |
| Evidence from mineral occurrences |
MRDS. |
| Geochemical evidence |
Numerous soil samples with enriched metal concentrations in literature. |
| Geophysical evidence |
Unknown. |
| Evidence from other sources |
Industry drilling and ore grade reports from the 1940s-90s. |
| Comments |
The deposit area is entirely encompassed within a wilderness area. Some select parcels of private ownership (former mines) exist, but access and feasibility of mining is extremely low. |
| Cover thickness and description |
Exposed at surface and reaches to some depth. |
| Authors |
Daniel W. Eungard. |
| New data needs |
High resolution mapping and geophysics. |
| Geologic mapping and modeling needs |
Partial mapping of three to four quadrangles at 1:24,000 scale or better resolution. |
| Geophysical survey and modeling needs |
High resolution aeromagnetic and aeroradiometric survey. Gravity may not be helpful with the similarity to the host/intrusive rock types. |
| Digital elevation data needs |
Lidar complete. |
