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Chinle Formation and associated rocks

CHINLE FORMATION AND ASSOCIATED ROCKS (Upper Triassic)-Continental deposits of variegated bentonitic claystone, siltstone, and clayey sandstone; ledge-forming sandstone; and red siltstone
State Nevada
Name Chinle Formation and associated rocks
Geologic age Late Triassic
Comments Primarily located in Clark County and southern Lincoln County; one outcrop in Elko County which could be correlative with the Chinle Formation as well as the Timothy Sandstone and Nugget Sandstone. The measured thickness of the Chinle Formation ranges from 750 to 3,300 feet (Longwell and others, 1965). The relative abundances of shale, siltsone, and sandstone are unspecified in referenced literture; the ranking of each of these units is speculative.
Primary rock type claystone
Secondary rock type siltstone
Other rock types sandstone; gypsum; conglomerate; limestone
Lithologic constituents
Major
Sedimentary > Clastic > Mudstone > Claystone (Bed)Includes bentonite.
Sedimentary > Clastic > Siltstone (Bed)
Minor
Sedimentary > Clastic > Sandstone (Bed)Possibly close to major in rank.
Incidental
Sedimentary > Chemical > Evaporite > Gypsum (Bed)
Sedimentary > Clastic > Conglomerate (Bed)Present only in basal Shinarump Member (Longwell and others, 1965).
Sedimentary > Carbonate > Limestone (Lense)
Map references
Stewart, J.H., and Carlson, J.E., 1978, Geologic Map of Nevada: U.S. Geological Survey and Nevada Bureau of Mines and Geology, 1:500,000 (not part of any formal series, printed and distributed by the U.S. Geological Survey, G75163, reprinted, 1981, G81386).
Unit references
Stewart, J.H., and Carlson, J.E., 1978, Geologic Map of Nevada: U.S. Geological Survey and Nevada Bureau of Mines and Geology, 1:500,000 (not part of any formal series, printed and distributed by the U.S. Geological Survey, G75163, reprinted, 1981, G81386).
Longwell, C.R., Pampeyaan, E.H., Bowyer, B., and Roberts, R.J., 1965, Geology and Mineral Deposits of Clark County, Nevada: Nevada Bureau of Mines and Geology Bulletin 62, 218 p., 16 pl.
Coats, R.R., 1987, Geology of Elko County, Nevada: Nevada Bureau of Mines and Geology Bulletin 101, 112 p., 1 pl.
Tschanz, C.M., and Pampeyan, E.H., 1970, Geology and Mineral Deposits of Lincoln County, Nevada: Nevada Bureau of Mines Bulletin 73, 187 p., 7 pl.
Counties Clark - Elko - Lincoln