Usage:
Austin Group (LA*,TX*)
Austin Chalk (TX*, and FL?,MS*-subsurface)
Subunits:
GROUP STATUS (alphabetical): Atco Formation (TX*), Blossom Sand (TX*), Bonham Clay (TX), Brownstown Formation (LA*,TX*) or Brownstown Marl (TX*), Bruceville Formation (TX*), Burditt Formation (TX) or Burditt Marl (TX*), Dessau Formation (TX*), Ector Chalk (LA,TX), Gober Chalk (TX*), Jonah Formation (TX) or Jonah Limestone (TX), McKown Formation (TX), Pflugerville Formation (TX), Rapides Formation (LA), Tokio Formation (LA*), Vinson Formation (TX).
FORMATION STATUS (alphabetical) --all in TX: Atco Member, Ector Tongue*, Gober Tongue[?], Hutchins Member.
Geologic age:
Late Cretaceous (Coniacian to early Campanian; Gulfian Provincial Epoch, Austinian Provincial Age)*
Type section, locality, area and/or origin of name:
Type area: Travis and Williamson Cos., central eastern TX. Named from Austin, in Travis Co. (US geologic names lexicons, USGS Bull. 896, 1200).
Type section (Austin Group): in vicinity of Austin, Williamson Co., central eastern TX (Murray, 1961, citing Durham, 1957, unpub. PhD dissert., Columbia Univ.).
AAPG geologic province:
East Texas basin*
Fort Worth syncline*
Gulf Coast basin*
Ouachita folded belt*
Permian basin*
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 ([ ]).