Named as a member of Carbondale Formation. Named for town of Dykersburg, Williamson Co., south-central IL. Consists of gray, silty shale. Thickness ranges from 4.6 to 30 m. Age is Middle Pennsylvanian (Desmoinesian).
Source: GNU records (USGS DDS-6; Reston GNULEX).
A nonmarine gray shale, equivalent to Dykersburg Shale Member of Carbondale Formation in IL, forms roof of Springfield Coal Member of Petersburg Formation in IN.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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