- Usage in publication:
-
- Galena series
- Modifications:
-
- Original reference
- AAPG geologic province:
-
- Wisconsin arch
- Iowa shelf
Summary:
Pg. 356-368. Galena series is here used to designate the formations that have been called Trenton group in Iowa, Illinois, Wisconsin, and Minnesota (Upper Mississippi Valley region). Age is Middle Ordovician.
[GNC remark (ca. 1936, US geologic names lexicon, USGS Bull. 896, p. 791): Included (descending) Galena dolomite, Decorah shale, and Platteville limestone of current nomenclature. The Galena and upper part of the Decorah are of Trenton age, but the Platteville is now generally considered to be of Black River age.]
Source: US geologic names lexicon (USGS Bull. 896, p. 791).
- Usage in publication:
-
- Trenton (Galena) group
- Modifications:
-
- Revised
- AAPG geologic province:
-
- Wisconsin arch
Summary:
Employed Trenton (Galena) group to include Galena limestone and Decorah shale of previous reports, but this was not adopted by Iowa, Illinois, Minnesota, and Wisconsin State Surveys, which adhered to Galena dolomite for the beds overlying Decorah shale.
Source: US geologic names lexicon (USGS Bull. 896, p. 791).
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 ([ ]).