Muddy Creek Formation

Usage of Geologic Unit Name:
Muddy Creek Formation (AZ*,CA*,NV*,UT*)

Muddy Creek Formation
Badlands in the Muddy Creek Formation near the eastern end of Lake Mead National Recreation Area.

Geologic Age:
Geologic Province:
Great Basin province*
Plateau sedimentary province*
Geologic Extent:
Type Locality:
Not designated. Named for Muddy Creek, Clark Co., NV (Longwell, 1928).
(alphabetical): Fortification Basalt Member (AZ*,NV*), Hualapai Limestone Member (AZ).
Unit Name History:
Name credited to C. Stock, 1921, GSA Bull., v. 32, p. 147 [abs]. First published use in a comprehensive report (Longwell, 1928). Overview; Revised, Fortification Basalt Member named (Longwell, 1963). Areal limits; Lower contact revised (Moore, 1972). Isotopic dating; Revised, Hualapai Formation reduced in rank and assigned as upper member of Muddy Creek (Blair, 1978). Overview; Areal limits (Bohannon, 1984). Isotopic dating (Hintze, 1986). Overview; Isotopic dating (Hintze and others, 1994). Mapped 1:24k; Overview (Williams and others, 1997).


Longwell, C.R., 1928, Geology of the Muddy Mountains, Nevada, with a section through the Virgin Range to the Grand Wash Cliffs, Arizona: U.S. Geological Survey Bulletin, 798, 152 p., (incl. geologic map, scale 1:250,000).

Longwell, C.R., 1963, Reconnaissance geology between Lake Mead and Davis dam, Arizona-Nevada, IN Shorter contributions to general geology, 1960-1964: U.S. Geological Survey Professional Paper, 374-E, p. E1-E51, (incl. geologic map, scale 1:125,000).

Moore, R.T., 1972, Geology of the Virgin and Beaverdam Mountains, Arizona: Arizona Bureau of Mines Bulletin, no. 186, 65 p., (incl. geologic map, scale 1:62,500).

Blair, W.N., 1978, Gulf of California in Lake Mead area of Arizona and Nevada during late Miocene time: American Association of Petroleum Geologists Bulletin, v. 62, no. 7, p. 1159-1170.

Bohannon, R.G., 1984, Nonmarine sedimentary rocks of Tertiary age in the Lake Mead region, southeastern Nevada and northwestern Arizona: U.S. Geological Survey Professional Paper, 1259, 72 p., (incl. geologic map, scale approx. 1:790,000).

Hintze, L.H., 1986, Stratigraphy and structure of the Beaver Dam Mountains, southwestern Utah, IN Thrusting and extensional structures and mineralization in the Beaver Dam Mountains, southwestern Utah: Utah Geological Association Publication, no. 15, p. 1-36.

Hintze, L.F., Anderson, R.E. and Embree, G.F., 1994, Geologic map of the Motoqua and Gunlock quadrangles, Washington County, Utah: U.S. Geological Survey Miscellaneous Investigations Series Map, I-2427, 7 p., 1 sheet, scale 1:24,000.

Williams, V.S., Bohannon, R.G. and Hoover, D.L., 1997, Geologic map of the Riverside quadrangle, Clark County, Nevada: U.S. Geological Survey Geologic Quadrangle Map, GQ-1770, 1 sheet, scale 1:24,000

Return to Main Page
* show accepted USGS usage.
Note that data on this page contains information that has been partly revised from bibliographic resources
available at the time this report was compiled.
The primary sources were the GeoRef Database and the National Geologic Map Database GEOLEX:
The URL is:
Last modified:8/10/2006