Thermal Maturity Patterns (CAI and %Ro) in the Ordovician and Devonian Rocks of the Appalachian Basin in West Virginia

摘要

This report presents a series of new thermal maturation maps for West Virginia, based on conodont color alteration index (CAI) and vitrinite reflectance (%Ro). Also, RockEval and total organic carbon (TOC) data are included in the report. Three Paleozoic intervals were studied: Middle Ordovician carbonate rocks, Lower and Middle Devonian carbonate rocks, and Middle and Upper Devonian black shale. These intervals were chosen for several reasons: (1) they represent target reservoir zones for most of the oil and gas exploration and drilling in West Virginia; (2) they are stratigraphically near probable source rocks for the oil and gas; (3) they include contiguous geologic formations that extend across most of West Virginia; (4) they contain carbonate grainstone/packstone which give a reasonable to good probability of recovery of conodont elements from small samples of drill cuttings; and (5) the Middle and Upper Devonian black shale contains large amounts of organic matter for geochemical analysis.