Usage:
Arkadelphia Marl (AR*,LA*,TX*)
Arkadelphia Formation (AR)
Arkadelphia Marl of Navarro Group (LA*,TX)
Geologic age:
Late Cretaceous (Maastrichtian; Gulfian Provincial Epoch)*
Type section, locality, area and/or origin of name:
Typical outcrops (modern sense) in southwestern AR: 5 to 7 mi north and northwest of Hope [Hempstead Co.]; along AR Highway 19, between U.S. Highway 30 and Prescott [Nevada Co]; and in the Oakhaven area [Hempstead Co.] (McFarland, 2004; see also Dane, 1929).
Named from outcrops at Arkadelphia, Clark Co., southwestern AR (Hill, 1888). [These strata no longer considered part of Arkadelphia (see Dane, 1929, McFarland, 2004).]
AAPG geologic province:
Anadarko basin*
Arkla basin*
East Texas basin*
Ouachita 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 ([ ]).