Usage:
Viola Springs Formation of Viola Group (OK)
Geologic age:
Late Ordovician (Mohawkian to Cincinnatian; Chattfieldian to Maysvillian)
Type section, locality, area and/or origin of name:
Type section: 1.5 mi southeast of Viola Springs, in NW/4 NE/4 sec. 19, T. 2 S., R. 8 E., Connerville NE quadrangle, Johnston Co., OK (Amsden, 1983).
AAPG geologic province:
South Oklahoma folded belt
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 ([ ]).