Oquirrh Mountains

Region West, Southwest
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Bingham is a giant porphyry Cu-Mo-Au system with associated skarn, manto, vein, and distal disseminated gold deposits. The Bingham Canyon mine has produced copper, gold, molybdenum, and silver from porphyry ore since the early 1900s. The focus area also encompasses the drilled Stockton porphyry copper deposit on west side of the Oquirrh Mountains and polymetallic (silver-lead-copper) skarn, polymetallic replacement and vein deposits, and sedimentary rock-hosted silver-gold-lead deposits in the Ophir district southwest of Bingham Canyon. Based on Bingham, Stockton and Ophir mining districts from Krahulec (2018b).
Identified resources Identified resources of copper, gold, molybdenum, and silver. Historical production of copper, gold, molybdenum, PGE, rhenium, silver, tellurium, and uranium.
Production In the Bingham district, there has been major mining since 1903. Mining through 2017 totaled more than 3.2 Gt of porphyry ore averaging 0.72% Cu, 0.057% MoS2, 0.012 oz/t Au 0.09 oz/t Ag from the Bingham Canyon mine; 8.9 Mt of skarn ore averaging 2.20% Cu, 0.077 oz/t Au, 1.32 oz/t Ag; 32.8 Mt replacement ore averaging 6.8% Pb, 2.8% Zn, 0.38% Cu, 3.65 oz/t Ag, 0.041 oz/t Au; 5.9 Mt of Cu-rich lodes averaging 2.05% Cu, 0.073 oz/t Au, 1.98 oz/t Ag, 0.2% Pb; 30.6 Mt of ore from distal disseminated deposits averaging 0.060 oz/t Au (Krahulec, 2018a). In the Stockton district, total production from polymetallic replacement deposits was about 2 Mt that averaged 7.7% Pb, 2.7% Zn, 0.3% Cu, 157 ppm Ag, and 1.27 ppm Au (Krahulec, 2018b). Mines in the Ophir district produced 2.8 Mt of ore that averaged 6.2% Pb, 1.5% Zn, 0.8% Cu, 237 ppm Ag, and 0.21 ppm Au (Krahulec, 2018b).
Status Past and current mining. Bingham Canyon mine produces byproduct Se, Te, Pd, Pt, sulfuric acid, and Pb carbonate (Rio Tinto, 2021b) and formerly recovered rhenium and uranium (John and Taylor, 2016). Other mines in the Bingham district and in the Ophir and Stockton districts are closed.
Estimated resources Bingham Canyon mine: 2020 end-of-year: 552 Mt of porphyry reserves at 0.44% Cu, 0.031% Mo, 0.16 ppm Au, and 2.11 ppm Ag, 285 Mt porphyry resources at 0.38% Cu, 0.017% Mo, 0.20 ppm Au, and 1.79 ppm Ag, and 20 Mt skarn resources at 3.65% Cu, 1.62 ppm Au, and 20.95 ppm Ag in the North Rim skarn (Rio Tinto, 2021a). Also, 2017 resources: 860 Mt of ore at 0.1 g/t In (Werner and others, 2017) and an estimated 3,230 Mt of ore at 10.1 ppb PGE John and Taylor, 2016). Stockton porphyry copper deposit: has estimated resources 170 Mt at 0.41% Cu, 0.14 ppm Au (Krahulec, 2015).
Geologic maps Laes and others (1997), scale 1:62,500; Clark and others (2017), scale 1:62,500; Clark and others (2012), scale 1:62,500; most of the area is covered with 1:24,000 mapping.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Eocene granitic porphyry intrusions, Upper Paleozoic sedimentary rocks (interbedded limestone and quartzite).
Deposits Bingham Canyon (MRDS dep_id: 10129805; USMIN Site_ID: UT00011), Carr Fork (USMIN Site_ID: US00011), Highland Boy, North Rim skarn, Lark, US, Barneys Canyon, Melco, many other small mines in the Bingham district. Ophir Hill and Hidden Treasure mines were the largest producers in Ophir district. The Calumet and Great Basin mines were the largest producers in the Stockton district.
Evidence from mineral occurrences MRDS; USMIN; UMOS (Utah Geological Survey, 2021).
Geochemical evidence Kocher (2017) and Brodbeck and others (2020) describe mineralogical residence of Bi, In, PGE, Re, Te, and W in porphyry ore at the Bingham Canyon mine. Tomlinson and others (2021) report trace element concentrations in sulfide minerals in polymetallic veins at Bingham Canyon. Rubright (1978) noted that polymetallic replacement deposits in the Ophir district contained minor W in wolframite and scheelite and anomalous Bi. At Bingham, trace element concentrations of porphyry Cu-Mo-Au ore are in Austen and Ballantyne (2010) and trace elements are in skarn ore in Cameron and Garmoe (1987). PGE analyses are in Tarkian and Stribrny (1999) and Cameron and Garmoe (1987). Trace elements in distal-disseminated ores are given in Presnell and Parry (1996) and Gunter and Austen (1998).
Geophysical evidence Unknown.
Evidence from other sources See Krahulec (2018b).
Comments Focus area encompasses the Bingham, Ophir, and Stockton mining districts. The Bingham district contains a giant porphyry Cu system with elevated Sn and W contents in porphyry ore that constitute a large mineral inventory. PGE, Re, Te, W, and U have been produced as byproducts of porphyry ore. Polymetallic replacement deposits produced significant Zn. Skarns locally are enriched in W and PGE. Distal disseminated deposits at Barneys Canyon and Melco were enriched in As. Polymetallic replacement deposits in the Ophir district were enriched in W and Bi.
Cover thickness and description Bingham and Ophir districts: no significant cover; Stockton district: apex of porphyry copper mineralization is ~300 m below surface (Krahulec, 2014).
Authors David A. John.
New data needs Regional aeromagnetics and aeroradiometrics survey; airborne hyperspectral would be useful in this area.
Geologic mapping and modeling needs Digitization and synthesis of existing maps to identify gaps.
Geophysical survey and modeling needs High-resolution, Rank 1 aeromagnetic and radiometric surveys.
Digital elevation data needs Lidar complete.