Usage:
Flour Sack Member of Bright Angel Shale of Tonto Group (AZ*-local)
Recognized locally in western Grand Canyon.
Geologic age:
Middle Cambrian*
Type section, locality, area and/or origin of name:
Not designated. Named from former rapids of that name 8 mi east of Grand Wash Cliffs, western Grand Canyon [Mohave Co., northwestern AZ] (McKee, 1945).
AAPG geologic province:
Plateau sedimentary province*
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 ([ ]).