Usage:
Cou Falls Member of Coralville Formation of Cedar Valley Group (IL,IA,MO)
Geologic age:
late Middle Devonian (Givetian)
Type section, locality, area and/or origin of name:
Mid River Marina quarry, in NW/4 NE/4 SE/4 sec. 27, T. 81 N., R. 7 W., Johnson Co., IA (Witzke and others, 1988).
AAPG geologic province:
Iowa shelf
Lincoln anticline
Wisconsin arch
Illinois basin
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 ([ ]).