Usage:
Spergen Limestone (IN*,IA,KS,MO,NE,OK, and CO*-subsurface)
Spergen Formation (IN*,OK)
Geologic age:
Mississippian
Meramecian
Missourian
Type section, locality, area and/or origin of name:
Named from Spergen Hill, near railroad station of Harristown, a few mi southeast of Salem, Washington Co., IN (Ulrich, 1904).
AAPG geologic province:
Anadarko basin
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 ([ ]).