Usage:
Morgan School Shale of Marmaton Group (IA)
Subunits:
Summit Coal Member (IA) [previously Summit coal of McGee (1885) in MO].
Geologic age:
Middle Pennsylvanian (Desmoinesian)
Type section, locality, area and/or origin of name:
Type section: in center of east line of NW/4 sec. 18, T. 72 N., R. 22 W., Lucas Co., IA. Named from former site of Morgan School, approx. 1 mi to southeast (Ravn and others, 1984).
AAPG geologic province:
Iowa shelf
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 ([ ]).