AN INTEGRATED PETROLEUM EVALUATION OF NORTHEASTERN NEVADA |
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NUGGET SANDSTONE Type Section Information The Nugget Formation was named for Nugget Station on the Oregon Shortline Railroad in southwestern Wyoming by Veatch (1907). Boutwell (1907) restricted the Nugget to about 500 feet of white sandstone in the Park City district, Utah. This restriction is equivalent to the lower part of the upper portion of the Nugget as defined by Veatch (1907). Geologic Age The Nugget Formation is Jurassic in age. General Lithology Within the evaluation area, the Nugget Sandstone only occurs in the Currie area. The Nugget unconformably overlies the Triassic Chinle Formation. It is composed of about 2,800 feet of white, pink, yellow, and red fine to medium-grained, crossbedded and friable sandstone (Nelson, 1956). These well sorted and well rounded sands contain raindrop impressions and ripple marks, as well as load casts, graded beds, slumps, and filled burrows (Nelson, 1956; Sirkin, 1970). Mineralogically the sands are composed of about 90 to 99 percent quartz, commonly with about 2 percent feldspar, and 2 percent chert grains (Sirkin, 1970). Average Thickness The Nugget Sandstone is about 2,150 feet thick in the Currie area (Sirkin, 1970). Areal Distribution The Nugget Sandstone is only exposed in the Currie area within the study area in northeastern Nevada. Depositional Setting The Nugget Sandstone probably represents recycled beach bar and dune sands. |
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