Delavan Member of Tiskilwa Formation of Wedron Group (IL)
Quaternary (Pleistocene; Wisconsinan)
Type section: roadcuts along Illinois Highway 121, 4 mi [6.4 km] east of Delavan, in SW/4 sec. 16, T. 22 N., R. 3 W., [Emden 7.5-min quadrangle], Tazewell Co., northeastern IL. Named from Delavan, Tazewell Co., northeastern IL (Willman and Frye, 1970).
Illinois basin
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