Usage:
Blackjack School Sandstone Member of Atoka Formation (OK*-recognized locally in Muskogee and McIntosh Cos.)
Geologic age:
Middle Pennsylvanian (Atokan)*
Type section, locality, area and/or origin of name:
Named from exposures at and around Blackjack School, in sec. 9, T. 11 N., R. 19 E., [Muskogee Co.], eastern OK (Wilson, 1935).
AAPG geologic province:
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 ([ ]).