| Basis for focus area |
Southeast Utah portion of tracts CP02 and CP03 from the National Assessment (U.S. Geological Survey National Mineral Resource Assessment Team, 2000) includes the Happy Jack and Lisbon Valley mine areas in Utah, Cashin mine area of western Colorado, and White Mesa area of northern New Mexico. Also includes Nacimiento Mountains, Jemez Springs, and Coyote, northwestern New Mexico. Utah areas also used mineral occurrence data and anomalous NURE stream sediment data. |
| Identified resources |
Historical and current production of copper. Historical production of gold, silver, uranium, and vanadium. |
| Production |
Lisbon Valley, Utah (1970-2007): produced 8.6 Mt ore at more than 1% Cu (Morrison and Parry, 1986); White Mesa, Arizona: 2.2 Mt @ 1% Cu (Mayo, 1956); Cashin mine, Colorado: 1,700,000 lbs Cu and 350,000 oz Ag (Withington, 1955); Happy Jack, Utah: 0.573 Mt @0.75% Cu, 0.25% U, and 0.047% V2O5: Nacimiento, New Mexico: 7.7 short tons Cu and 76,000 oz Ag (McLemore, 2017). |
| Status |
Past mining. Lisbon Valley (Utah) is an operating copper mine. Nacimiento mine (New Mexico) is in reclamation after attempts to in situ leach; reserves remain. |
| Estimated resources |
Lisbon Valley: (2007) total reserves and resources 68.3Mt @0.522% Cu; Cashin mine: Proven and Probable reserves, plus Measured and Indicated resources 11.75 Mt @ 0.52% Cu (Constellation Copper Corp. press release, July 20, 2004); Nacimiento: estimated 9.6 million lbs Cu as in-place reserves with Cu grade about 0.7% Cu (Woodward, McLelland and Husler, 1974). |
| Geologic maps |
Withington (1955), scale, 1:24,000; Hite (1978), scale, 1:24,000; Isachsen (1954), scale, 1:72,000; Woodward, McLelland and Kaufman (1974), scale1:24,000. |
| Geophysical data |
Byerly and Joesting (1959) provides regional geophysics. |
| Favorable rocks and structures |
Lisbon Valley fault, Lisbon Valley salt anticline, Burro Canyon Formation, Cashin fault, Paradox Valley anticline, Wingate Sandstone, Abo and Chinle redbeds in New Mexico. |
| Deposits |
Cashin mine (MRDS dep_id: 10014257), Lisbon Valley Copper mine (MRDS dep_id: 10276693), Happy Jack mine (MRDS dep_id: 10055176), Nacimiento mine (MRDS dep_id: 10151101), Coyote Hill mine (MRDS dep_id: 10089317). |
| Evidence from mineral occurrences |
MRDS; UMOS (Utah Geological Survey, 2021). |
| Geochemical evidence |
Happy Jack mine: Ilsemannite and erythrite are secondary minerals found locally, signaling anomalous Mo and Co, respectively. Black manganese oxides with greater than 10% Co are locally found. Geochemical data from ore shipments: (all data in ppm): X-ray spectrography: 15,000 Al, 30,000 Fe, 70 Mn, 1,500 Ca, 700 Mg, 1,500 Ti, 300 Na, 150 Ba, 70 Sr, 150 Zr, 30 Cr, 15 Sc, 15 B, 30 Y, 540 V: quantitative spectrography: 30 Ni, 700 Co, 7,000 Cu, 150 Pb, 7,700 U: fluorometric: 70 Mo, 3 Ag, 1.5 Be, 1,500 Zn (Hayes and others, 2015). |
| Geophysical evidence |
Unknown. |
| Evidence from other sources |
See Krahulec (2018b); McLemore (2017). |
| Comments |
Utah areas are based on mines with historical production where Cu was listed as either a major or minor commodity (Utah Geological Survey, 2021). Majority of sites are hosted in the Chinle. Nacimiento deposits in New Mexico have mine wastes and ARD that should be examined for potential critical minerals. A detailed geochemical sampling survey along with geologic mapping would determine if any of these deposits have potential for Co, Ga, Ge, PGE, Re, U, V, and Zn. |
| Cover thickness and description |
Variable-some exposed with surface workings as pits and trenches, shallow shafts. |
| Authors |
Jane M. Hammarstrom, Virginia T. McLemore, Stephanie Mills. |
| New data needs |
Modern geochemical reanalysis of samples from NURE sediment program; digitized and updated mapping; regional aeromagnetic and aeroradiometric surveys (Utah). Geochemistry of the Nacimiento and other New Mexico sedimentary rock-hosted Cu deposits. |
| Geologic mapping and modeling needs |
Digitization and synthesis of existing maps to identify gaps (Utah); mapping in New Mexico districts. |
| Geophysical survey and modeling needs |
High-resolution, Rank 1 aeromagnetic and radiometric surveys.(New Mexico submitted a geophysical request for the Nacimiento area). |
| Digital elevation data needs |
Lidar variable across large focus area; some complete, some in progress, some inadequate. |
