Figs. 3, 15B. Everett member of Nachusa formation. Shown on columnar section as uppermost member of Nachusa formation; overlies Elm member (new); underlies Hazel Green member (new) of Quimbys Mill formation. Thickness 2 to 6 feet. Age is Middle Ordovician.
[Notable exposures in Dixon-Oregon area, northern IL.]
Source: US geologic names lexicon (USGS Bull. 1200, p. 1301).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
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