| Basis for focus area |
Recent exploration at Big Iron; check other exploration sites that mention W as one of several commodities. |
| Identified resources |
Historical production of copper, silver, and zinc. |
| Production |
Unknown. |
| Status |
Past mining. |
| Estimated resources |
Unknown. |
| Geologic maps |
Fox (1981), scale 1:24,000; Yates (1971), scale 1:31,680. |
| Geophysical data |
75% mapped at Rank 3 aeromagnetic and Rank 2 aeroradiometric, remaining is inadequate. |
| Favorable rocks and structures |
Limestone and graywacke of the Permian Mt Roberts Formation intruded by Jurassic basic sill and Eocene basic and acidic dikes at big iron. At Minorca Eocene intrusions are dacite to rhyodacite with ore occurring a lodes. |
| Deposits |
Big Iron mine (MRDS dep_id: 10008903). |
| Evidence from mineral occurrences |
MRDS. |
| Geochemical evidence |
Unknown. |
| Geophysical evidence |
Unknown. |
| Evidence from other sources |
Unknown. |
| Comments |
Mostly national forest with some state land (mineral leases) and BLM. |
| Cover thickness and description |
Exposed at the surface. |
| Authors |
Daniel W. Eungard. |
| New data needs |
High resolution mapping, geophysics. |
| Geologic mapping and modeling needs |
50% mapped at a scale of 1:24,000 with remainder at scales of 1:48,000 to 1:62:500. |
| Geophysical survey and modeling needs |
75% mapped at QL3 aeromagnetic and QL2 aeroradiometric, remaining is lower QL. Need higher resolution aeromagnetic data as aeroradiometric data likely not useful for this deposit type. |
| Digital elevation data needs |
Lidar complete. |
