Usage:
Coggon Member of Otis Formation of Wapsipinicon Group (IL,IA)
Coggon Member of Wapsipinicon Limestone (IL,IA)
Geologic age:
early Middle Devonian (Eifelian)
Type section, locality, area and/or origin of name:
Coggon, at crossing of Buffalo River by Illinois Central Railway, Linn Co., east-central IA (Norton, 1921).
AAPG geologic province:
Iowa shelf
Wisconsin arch
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 ([ ]).