Usage:
No current usage.
(Rocks of †Ruddell Shale (AR*) reallocated to Moorefield Formation. See Moorefield.)
Geologic age:
Late Mississippian (Chesterian)*
Type section, locality, area and/or origin of name:
Not designated though unit is nearly completely exposed along Batesville-Bethesda Road, in NE/4 NE/4 sec. 13, T. 7 N., R. 13 W. Origin of name not stated by author, but probably named from exposures on the west end of Ruddell Hill, Independence Co., AR (Gordon, 1944).
Type locality: on west end of Ruddell Hill, near Ruddell's mill, in Ruddell civil Twp., Independence Co., AR (Gordon and Kinney, 1944).
AAPG geologic province:
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 ([ ]).