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

John E. Repetski; Robert T. Ryder; John A. Harper; Michael H. Trippi

doi:10.3133/ofr2002302

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

John E. Repetski·Robert T. Ryder·John A. Harper·Michael H. Trippi

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Abstract

This report presents a series of new thermal maturation maps for Pennsylvania, based on conodont color alteration index (CAI) and vitrinite reflectance (%R o ). 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.

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Source-reported bounding extent: 39.7198° to 42.26986° latitude; -80.519891° to -74.689516° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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John E. Repetski, Robert T. Ryder, John A. Harper, Michael H. Trippi. 2002. Thermal maturity patterns (CAI and %Ro) in the Ordovician and Devonian rocks of the Appalachian basin in Pennsylvania. https://doi.org/10.3133/ofr2002302

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