- Usage in publication:
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- Dygerts Bentonite Bed
- Modifications:
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- Original reference
- Dominant lithology:
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- Bentonite
- AAPG geologic province:
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- Wisconsin arch
Summary:
Pg. 52. Dygerts Bentonite Bed of Sinsinawa Member of Wise Lake Formation. Present in Illinois, Iowa, and Minnesota. Consists of bentonite clay; thickness 0.05 m at type section. Overlies and underlies dolomite units near middle of Sinsinawa Member. Age is Middle Ordovician.
Type section: Galena Roadcut Section, on U.S. Highway 20 along east side of Galena River, in SW/4 SE/4 NE/4 sec. 20, T. 28 N., R. 1 E., in Galena, Jo Daviess Co., northwest IL. Named from Dygerts Mound, 2.4 km southeast of type section.
Source: US geologic names lexicon (USGS Bull. 1564, p. 51).
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 ([ ]).