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National Geologic Map Database
Geologic Unit: Galena
Map showing publication footprint
  • Usage in publication:
    • Galena series
  • Modifications:
    • Original reference
  • AAPG geologic province:
    • Wisconsin arch
    • Iowa shelf
Publication:

Sardeson, F.W., 1896, The Galena and Maquoketa shales, Part 1: American Geologist, v. 18, p. 356-368.


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).


Map showing publication footprint
  • Usage in publication:
    • Trenton (Galena) group
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Wisconsin arch
Publication:

Trowbridge, A.C., 1935, [Road logs and stratigraphic sections], IN Kay, G.F., and Trowbridge, A.C., Conference leaders, Upper Mississippi Valley, Iowa City, Iowa, to Duluth, Minnesota: Kansas Geological Society Guidebook for the Annual Field Conference, August 25-September 1, 1935, no. 9, p. 1-236, 423-471., Prepared in cooperation with Iowa, Illinois, Wisconsin, and Minnesota geol. surveys


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 usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).