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Stratigraphic Framework of Cambrian and Ordovician Rocks in the Central Appalachian Basin from Medina County, Ohio, through Southwestern and South-Central Pennsylvania to Hampshire County, West Virginia

By Robert T. Ryder, Anita G. Harris, and John E. Repetski

Revised and digitized by Robert D. Crangle, Jr.

Version 2.0 (2003)
(Originally published in 1992)


Oil and gas exploration in the Ohio, Pennsylvania, and West Virginia parts of the Appalachian basin, from the late 1950's to the middle 1980's, resulted in the drilling of a modest number of holes into Cambrian strata and (or) Precambrian basement rocks. On the basis of geophysical and lithologic logs from these drill holes and paleontologic data from one of these holes, we have drawn a 275-mi-long restored stratigraphic cross section through the Cambrian and Ordovician sequence from Medina County, Ohio, through southwestern and south-central Pennsylvania to Hampshire County, W. Va. (section C-C'). The stratigraphic framework of the Cambrian and Ordovician sequence along this cross section and, to a lesser extent, the structure of the underlying block-faulted basement rocks are the main topics of this paper.


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All file formats will produce a plot that faithfully replicates the format, symbols, colors, and line work of a USGS full-color printed map. (The actual published paper maps are 4-color offset-printed maps.) The PDF file is 2.6 MB, the EPS file is 17.6 MB, and the AI file is 2.6 MB.  Page size at 100% is approximately 39" by 36".  Plot resolution, quality, and colors will vary with plotter, inks, and paper used. Adobe Acrobat Reader 4 and Adobe Illustrator 9.0 or later is required to read the map. On the PC, right-click to save file to your hard disk; on the Macintosh, click and hold.

Restored Stratigraphic Section of C-C', Plate 1  [2.2 MB PDF file]
Restored Stratigraphic Section of C-C', Plate 1  [17.6 MB EPS file]  -- CAUTION, LARGE FILE SIZE
Restored Stratigraphic Section of C-C', Plate 1  [2.6 MB AI file]


Text to U.S. Geological Survey Bulletin 1839-K [415 KB PDF file] (Figures and tables are located on Plate 1.)

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Contact: Robert T. Ryder or Robert D. Crangle, Jr.
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