No current usage?
(Purgatoire Formation (CO*,NM*,OK*) considered abandoned? Uncertain if used by the CO, NM, and OK Geol. Surveys or the USGS. Possibly considered same as Lytle Sandstone and Glencairn Formation. See Lytle and Glencairn.)
(alphabetical): Cheyenne Sandstone Member (CO*,NM,OK*), Glencairn Shale Member (CO*), Kiowa Shale Member (CO*,NM,OK*), Lytle Sandstone Member (CO*).
late Early Cretaceous (Albian)*
Not designated. Name from Purgatoire Canyon, Mesa de Maya quadrangle, Las Animas, Otero, and Bent Cos., CO (Stose, 1912).
Sierra Grande uplift*
Palo Duro basin*
Las Vegas-Raton basin*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.
"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).