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Stratigraphic framework of Cambrian and Ordovician rocks in the Appalachian Basin from Sequatchie County, Tennessee through eastern Kentucky, to Mingo County, West Virginia

October 7, 2008

Cross section H-H' is the seventh in a series of restored cross sections constructed by the lead author to show the stratigraphic framework of Cambrian and Ordovician rocks in the Appalachian basin from Pennsylvania to Tennessee. The sections show complexly intertongued carbonate and siliciclastic lithofacies, marked thickness variations, key marker horizons, unconformities, stratigraphic nomenclature of the Cambrian and Ordovician sequence, and major faults that offset Proterozoic basement and overlying lower Paleozoic rocks. Several of the drill holes along the cross section have yielded a variety of whole and (or) fragmented conodont elements. The identifiable conodonts are used to differentiate strata of Late Cambrian, Early Ordovician, and Middle Ordovician age, and their conodont color alteration index (CAI) values are used to establish the thermal maturity of the sequence. Previous cross sections in this series are G-G', F-F', E-E', D-D', C-C', and B-B'. Many of these cross sections (B-B', C-C', D-D', and G-G') have been improved with the addition of gamma-ray log traces, converted to digital images, and made accessible on the Web.

Publication Year 2008
Title Stratigraphic framework of Cambrian and Ordovician rocks in the Appalachian Basin from Sequatchie County, Tennessee through eastern Kentucky, to Mingo County, West Virginia
DOI 10.3133/sim2994
Authors Robert T. Ryder, Robert D. Crangle, John E. Repetski, Anita G. Harris
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Scientific Investigations Map
Series Number 2994
Index ID sim2994
Record Source USGS Publications Warehouse
USGS Organization U.S. Geological Survey