Bonpas Limestone Member of Mattoon Formation of Mcleansboro Group (IL-local)
Late Pennsylvanian (Missourian)
Type locality: in NE/4 NE/4 NE/4 sec. 6, T. 2 N., R. 14 W., Olney quadrangle, Richland Co., southeastern IL. Named from Bonpas Creek, about 1.5 mi east of type outcrop (Kosanke and others, 1960).
Illinois basin
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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