Usage:
Francis Formation (OK*-recognized locally in Pontotoc and Seminole Cos.)
Subunits:
DeNay Limestone Member (OK*).
Geologic age:
Late Pennsylvanian (Missourian)*
Type section, locality, area and/or origin of name:
Town of Francis, which is situated on eastern edge of outcrop, northeastern Pontotoc Co., central southern OK, and "all that portion of the outcrop which extends for a distance of 3 mi north, and for a similar distance south of Canadian River," Stonewall quadrangle, Pontotoc Co., OK. Named from town of Francis (Morgan, 1924; see also Tanner, 1956).
AAPG geologic province:
Arkoma basin*
Chautauqua platform*
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 ([ ]).