GEOLEX database Geologic Unit: Redonda Usage: Redonda Formation* Age: Triassic, Late* Geologic Province: Sierra Grande uplift* Palo Duro basin* Las Vegas-Raton basin Areal Extent: NM(ec)* Type Locality: Not designated. Derivation of name not stated by authors, but probably named from Redonda Mesa, Quay Co., NM (Dobrovolny and Summerson, 1946). Unit Name History: Name proposed for the upper member of Chinle Formation (Dobrovolny and Summerson, 1946). Raised to formation rank (Griggs and Read, 1959). Revised (Lucas and Hunt, 1989). Areal limits (Lucas and others, 1990). Note: If you need more information, please contact Nancy Stamm (nstamm@usgs.gov). Asterisks (*) indicate usage by the U.S. Geological Survey. Other usages by state geological surveys. "No current usage" implies that a name has been abandoned or that it has fallen into disuse. Former usage and, if known, replacement name given in parentheses (). Slashes (/) indicate unit name usage violates the 1983 North American Stratigraphic Code. This violation may be explained within brackets ([ ]). U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA URL http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html Database project personnel Last modified: 7-Jan-2007