Named as a member of Draneros shale of Colorado group for the town of Newcastle, Weston Co, WY in Powder River basin, where member is conspicuously developed.[1]
Consists of reddish to light-yellow sandstone associated with black, carbonaceous shale. About 35 ft thick in vicinity of Newcastle. A Cretaceous sequence can be formed in the northern Great Plains in Williston and Powder River basins, as well as Chadron arch.
This area is classed as a formation on the westrin rim of the black hills.
[1] Hancock, E.T., 1920, The Mule Creek oil field, Wyoming, IN Contributions to economic geology, 1920; Part 2, Mineral fuels: U.S. Geological Survey Bulletin, 716-C, p. C35-C53.
[2] Reeside, J.B., Jr., 1944, Maps showing thickness and general character of the Cretaceous deposits in the Western Interior of the United States: U.S. Geological Survey Oil and Gas Investigations Preliminary Map, OM-10, scale 1:13,939,200
[3] Cobban, W.A., and Reeside, J.B., Jr., 1952, Correlation of the Cretaceous formations of the Western Interior of the United States: Geological Society of America Bulletin, v. 63, no. 10, p. 1011-1044.
