Usage:
Pearlette family ash bed (informal) (CO*,IA*,KS*,NE*,OK*,SD*,TX*)
(†Pearlette Ash Member of Sappa Formation* abandoned.)
Informal. The rank or lithologic term should not be capitalized.
Geologic age:
late Tertiary and Quaternary (late Pliocene and Pleistocene)*
Due to change in Plio-Pleistocene boundary, age may now be considered all or in part Pleistocene.
Type section, locality, area and/or origin of name:
Named from old post office of Pearlette, Meade Co., southwestern KS (Cragin, 1896).
AAPG geologic province:
Anadarko basin*
Central Kansas uplift*
Cherokee basin*
Denver basin*
Forest City basin*
Iowa shelf*
Las Animas arch*
Nemaha anticline*
Palo Duro basin*
Permian basin*
Salina basin*
Sedgwick basin*
Sioux uplift*
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 ([ ]).