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Minor podiform chromite deposit, 5 of 5 in Amador county (in California)
Sections of this page: [Geologic] - [Economic] - [Reference]
| Country | United States |
|---|---|
| State or province | California |
| Geographic location: | 38°29'30"N,
120°54'56"W (-120.915556, 38.491667) |
| Geographic context: | (click for info) |
| Deposit type | minor podiform chromite |
| Model type | Minor Podiform |
| Deposit form | lenses |
| Deposit texture | coarse-grained disseminated, coarse-grained massive |
| Ore type | Unknown |
| Age of deposit | Pennsylvanian (311±3 m.y. 206Pb/238U) |
| Age (m.y.) | 311million years |
| Mineralogy | chromite |
| Host rock type | serpentinized dunite |
| Host rock length | 52000 |
| Host rock width | 2000 |
| Ophiolite zone | tectonite |
| Deposits < 10km | podiform chromite |
| Rocks within 5km | serpentinized dunite harzburgite basalt flow basalt tuff slate graywacke conglomerate mudstone quartzite chert gabbro greenstone andesite flow andesite tuff andesite breccia rhyolite flow rhyolite tuff sandstone siltstone claystone |
| Geologic map unit | -120.915555555556, 38.4916666666667 |
| Nearby scientific data | Find additional scientific data near this location |
| Tonnage | 0.000191 | million metric tons |
|---|---|---|
| Ore depth | 0 | m |
| Cr2O3 grade | 38 | percent |
| Comments | Bear Mountain ophiolitic melange. Amador County. |
|---|---|
| References | 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. Cater, F.W., Jr., 1948, Chromite deposits of Calaveras and Amador counties, California, in Geological investigations of chromite in California, Part 3--Sierra Nevada: California Division of Mines Bulletin 134, pt. 3, ch. 2, 60 p. Saleeby, J.B., 1982, Polygenetic ophiolite belt of the California Sierra Nevada--Geochronological and tectonostratigraphic development: Journal of Geophysical Research, v. 87, no. B3, p. 1803-1824. |