Usage:
Jackfork Group (AR,OK*)
Jackfork Sandstone (AR*,OK)
Subunits:
GROUP STATUS (alphabetical): Brushy Knob Formation (AR), Chickasaw Creek Chert (OK), Game Refuge Formation (OK) or Game Refuge Sandstone (OK*), Irons Fork Mountain Formation (AR), Markham Hill Formation (OK*), Prairie Hollow Shale (OK), Prairie Mountain Formation (OK*), Wesley Formation (OK) or Wesley Shale (OK*), Wildhorse Mountain Formation (OK*).
Geologic age:
Mississippian, Late* (local)
Chesterian* (local)
Pennsylvanian, Early*
Morrowan*
Type section, locality, area and/or origin of name:
Not designated. Named from Jackfork Mountain, Pittsburg and Pushmataha Cos., OK (Taff, 1902).
AAPG geologic province:
Ouachita folded belt*
Arkoma 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 ([ ]).