Pg. 33, figs. 3, 9. Beecher member of Dunleith formation. Dolomite, pure, nonshaly, noncherty; thick-bedded. Thickness about 3.5 feet. Shown on columnar section as underlying Eagle Point member (new) and overlying St. James member (new). Age is Middle Ordovician.
[Notable exposures in Dixon-Oregon area, northern IL.]
Source: US geologic names lexicon (USGS Bull. 1200, p. 271).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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