Usage:
Douglas Group (IA*,KS*,MO*,NE*, and CO*-subsurface)
Subunits:
(alphabetical): Cass Limestone (IA,NE) or Cass Formation (MO), Iatan Limestone (KS), Lawrence Formation (KS*,NE*,MO) or Lawrence Shale (IA*,KS*,MO*), Plattford Shale (NE), Stranger Formation (KS*,MO*,NE*).
Geologic age:
Late Pennsylvanian (Missourian to Virgilian)*
Type section, locality, area and/or origin of name:
Named from Douglas Co., eastern KS (Haworth, 1898).
AAPG geologic province:
Anadarko basin*
Forest City basin*
Cherokee 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 ([ ]).