Usage:
Toroweap Formation (AZ*,NV*,UT*)
Toroweap Marble (CA*)
Subunits:
(alphabetical): Brady Canyon Member (AZ*,NV*), Seligman Member (AZ*), Woods Ranch Member (AZ*,NV*).
Geologic age:
early Permian (late Leonardian)*
Type section, locality, area and/or origin of name:
Type section: on east wall of Toroweap Valley, Grand Canyon National Monument, about 9 mi above mouth and 8 mi north of Colorado River, Mohave Co., AZ (McKee, 1938).
Reference section: from southwest corner sec. 12, T. 33 N., R. 9 W., to top of Huricane Cliffs, Whitmore Point 7.5-min quadrangle, Mohave Co., AZ (Sorauf and Billingsley, 1991).
AAPG geologic province:
Plateau sedimentary province*
Great Basin province*
Paradox basin
Wasatch uplift*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).