Masuk Member of Mancos Shale

Usage of Geologic Unit Name:
Masuk Member of Mancos Shale (UT*)
Masuk Tongue of Mancos Shale (UT)
Masuk Formation (UT)
Cretaceous, Late*
Geologic Province:
Paradox basin*
Areal Extent:
Type Locality:
Not designated. Probably named from Masuk Plateau (Gilbert, 1880). Type section: east side of Blind Trail on west-facing cliff, SE/4 NE/4 sec. 27, T. 31 S., R. 8 E. through SW/4 NW/4 sec. 26, T. 31 S., R. 8 E., Garfield Co., UT (Eaton, 1990).
Unit Name History:
First used as Masuk Shale (Gilbert, 1880). Areal limits; Revised (Sargent and Hansen, 1982). Geographically restricted to Henry Mountains, Paradox basin (Fouch and others, 1983). Revised (Smith, 1983). Removed from Mancos, raised rank to Masuk Formation (Eaton, 1990).

Gilbert, G.K., 1880, Report on the geology of the Henry Mountains: U.S. Geological and Geographical Survey, Rocky Mountain region, 2nd edition, 170 p.

Sargent, K.A. and Hansen, D.E., 1982, Bedrock geologic map of the Kaiparowits coal-basin area, Utah: U.S. Geological Survey Miscellaneous Investigations Series Map, I-1033-I, 1 sheet.

Smith, Curtis, 1983, Geology, depositional environments, and coal resources of the Mt. Pennell 2 NW quadrangle, Garfield County, Utah: Brigham Young University Geology Studies, v. 30, pt. 1, p. 145-169.

Fouch, T.D., Lawton, T.F., Nichols, D.J., Cashion, W.B. and Cobban, W.A., 1983, Patterns and timing of synorogenic sedimentation in Upper Cretaceous rocks of central and northeast Utah, IN Reynolds, M.W., and Dolly, E.D., editors, Mesozoic paleogeography of the west-central United States: Society of Economic Paleontologists and Mineralogists, Rocky Mountain Section, Rocky Mountain Paleogeography Symposium, v. 2, p. 305-336.

Eaton, J.G., 1990, Stratigraphic revision of Campanian (Upper Cretaceous) rocks in the Henry basin, Utah: The Mountain Geologist, v. 27, no. 1, p. 27-38

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Last modified: 1/7/2011