Previous record: 117 Next record: 119

Simon South

Minor podiform chromite deposit, 22 of 29 in El Dorado county (in California)

Sections of this page: [Geologic] - [Economic] - [Reference]

Geologic Information
CountryUnited States
State or provinceCalifornia
Geographic location:38°49'45"N, 120°52'47"W
(-120.879722, 38.829167)
Geographic context: (click for info)
Deposit typeminor podiform chromite
Model typeMinor Podiform
Deposit formsmall stringers
Deposit texturemedium-grained massive, disseminated
Ore typeUnknown
Age of depositpre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)
Age (m.y.)388million years
Area of deposit27.6sq m
Ore body length6m
Ore body width4.6m
Host rock typeserpentinized dunite
Host rock length6500
Host rock width3500
Paleotectonic settingsuprasubduction
Ophiolite zonetectonite
Deposits < 10kmpodiform chromite
Rocks within 5kmserpentinized dunite
basalt flow
basalt tuff
andesite flow
andesite tuff
andesite breccia
rhyolite flow
rhyolite tuff
Geologic map unit-120.879722222222, 38.8291666666667
Nearby scientific dataFind additional scientific data near this location
Economic Information
Discovery date1916
Startup date1916
Tonnage3e-05million metric tons
Mine depth3m
Ore depth0m
Cr2O3 grade35percent
Reference information
CommentsLocation uncertain, but is 244 m south of Simon North workings. Production of 30 t of ore @ 35% Cr2O3 is estimated from pit size. Feather River Belt. El Dorado County.
Mayfield, J.D., and Day, H.W., 2000, Ultramafic rocks in the Feather River Belt, northern Sierra Nevada, California, in Brooks, E.R., and Dida, L.T., eds., Field guide to the geology and tectonics of the northern Sierra Nevada, National Association of Geoscience Teachers Far-Western Section Fall Conference 2000: California Division of Mines and Geology Special Publication 122, p. 1-15.
Cater, F.W., Jr., Rynearson, G.A., and Dow, D.H., 1951, Chromite deposits of El Dorado County, California, in Geological investigations of chromite in California, Part 3--Sierra Nevada: California Division of Mines Bulletin 134, pt. 3, ch. 4, 167 p.
Wagner, D.L., Jennings, C.W., Bedrossian, T.L., and Bortugno, E.J., 1981, Geologic map of the Sacramento quadrangle: California Division of Mines and Geology Regional Geologic Map Series Map no. 1A, scale 1:250,000.
Ehrenberg, S.N., 1975, Feather River ultramafic body, northern Sierra Nevada, California: Geological Society of America Bulletin, v. 86, p. 1235-1243.
Show this information as [XML] - [GeoJSON]