Modoc Limestone (AZ*-recognized locally in Clifton 15-min quadrangle)
Mississippian*
Not designated. Presumably named from Modoc Mountain, near Morenci, Greenlee Co., AZ (Lindgren, 1905).
Basin-and-Range province
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 ([ ]).