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Thermal maturity patterns (CAI and %Ro) in the Ordovician and Devonian rocks of the Appalachian basin in Pennsylvania

October 1, 2002

 This report presents a series of new thermal maturation maps for Pennsylvania, based on conodont color alteration index (CAI) and vitrinite reflectance (%Ro). Also, RockEval and total organic carbon (TOC) data are included in the report. Two Paleozoic intervals were studied: Middle Ordovician carbonate rocks and Lower and Middle Devonian carbonate rocks and black shale. These intervals were chosen for several reasons: A) they represent target reservoir zones for most of the oil and gas exploration and drilling in Pennsylvania; B) they are stratigraphically near probable source rocks for the oil and gas; C) they include contiguous geologic formations that extend across most of Pennsylvania; D) they contain carbonate grainstone/packstone which give a reasonable to good probability of recovery of conodont elements from small samples of drill cuttings; and E) the Middle Devonian black shale contains large amounts of organic matter for geochemical analysis.

Publication Year 2002
Title Thermal maturity patterns (CAI and %Ro) in the Ordovician and Devonian rocks of the Appalachian basin in Pennsylvania
DOI 10.3133/ofr2002302
Authors John E. Repetski, Robert T. Ryder, John A. Harper, Michael H. Trippi
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2002-302
Index ID ofr2002302
Record Source USGS Publications Warehouse