Spence Tongue of Lead Bell Shale (ID*,UT*)
Spence Shale Member of Langston Dolomite (ID,UT)
Spence Shale Member of Langston Formation (UT)
Middle Cambrian*
Type locality: Spence Gulch, a ravine running up into Danish Flat from Mill Canyon, about 5 mi west-southwest of Liberty, Bear Lake Co., southeastern ID (Walcott, 1908).
Wasatch 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 ([ ]).