| Basis for focus area |
Historical fluorite producer from veins in sheeted zone associated with Tertiary rhyolitic tuffs and breccias (U.S. Geological Survey, 1968a). Fissure vein striking to the northeast with the main load developed to a depth over 700 feet in the Oligocene Farmers Creek Tuff, as described in Brady (1975), which indicates that it occurs in the Wagon Wheel Gap volcanic rock sequence. The principal vein averages 6 to 8 feet with a maximum width of about 35 feet (Brady, 1975). Outline includes the 1:500,000 scale mapping of volcanic rocks in this area as well as some surficial deposits that may cover these deposits (from Tweto, 1979). |
| Identified resources |
Historical fluorite production. |
| Production |
Production was reportedly from 1939 to 1950. Value of fluorite production between 1947 and 1950 was approximately $420,426 (Schwochow and Hornbaker, 1985). |
| Status |
Past mining of fluorite from 1911 to 1950, except 1932, 1933, and 1938 (U.S. Geological Survey, 1968b). |
| Estimated resources |
Brady (1975) indicates reserves of greater than 250,000 short tons fluorite at Wagon Wheel Gap. Metallurgical-grade fluorspar mined exceeded $674,000 in value up to 1950 (Brady, 1975). |
| Geologic maps |
Steven and Ratté (1973), scale 1:62,500; Steven and Lipman (1973), scale 1:62,500; Steven (1968), scale 1:20,000; Lipman (2006), scale 1:50,000. |
| Geophysical data |
Inadequate aeromagnetic and aeroradiometric coverage. |
| Favorable rocks and structures |
Fissure veins in the Oligocene Farmers Creek Tuff. |
| Deposits |
Wagon Wheel Gap (MRDS dep_id: 10014057). |
| Evidence from mineral occurrences |
MRDS. |
| Geochemical evidence |
Historical mining and production of fluorspar. Barite occurs nearer to the surface with less below 25 feet and absent below 100 feet. |
| Geophysical evidence |
No data. |
| Evidence from other sources |
This is a historical fluorspar mining district. |
| Comments |
Vein first discovered while searching for Au and Ag. Low Au and Ag values did not generate much interest, but fluorite recognized in 1911. Barite, calcite, and chalcedony are gangue minerals. |
| Cover thickness and description |
Fissure veins thought to extend in the subsurface over 400 feet in volcanic tuff. |
| Authors |
Michael K. O'Keeffe. |
| New data needs |
1:24,000 scale geologic mapping of two quadrangles. Lidar data would also be needed. |
| Geologic mapping and modeling needs |
1:24,000 scale geologic mapping at the Lake Humphreys and Wagon Wheel Gap quadrangles. A portion of the Lake Humphreys quadrangle is mapped at 1:24,000 (Lipman, 2006). |
| Geophysical survey and modeling needs |
Rank 1 aeromagnetics and aeroradiometrics would help put things into context. |
| Digital elevation data needs |
Lidar inadequate. |
