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National Geologic Map Database

Geologic Unit: Toroweap

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 usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).