Usage:
Blackford Member of Banner Formation (IN-local)
Blackford Member of Jessup Formation (OH, and IN-local)
(The Blackford is a member of the Banner Formation in eastern IN and of the Jessup Formation in western IN.)
Geologic age:
Quaternary (Pleistocene)
Type section, locality, area and/or origin of name:
Type section (subsurface): DNR test hole 17, 10 ft west of Grant-Blackford Co. line, in NE/4 NE/4 NE/4 sec. 13, T. 26 N., R. 3 E., Grant Co., IN (Bleuer, 1991).
AAPG geologic province:
Cincinnati 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 ([ ]).