May 19, 2017
Pennsylvania Geological Survey presented on recently reinterpreted stratigraphy at the Geological Society of America Northeastern Section meeting in Pittsburgh. As a member of the Eastern Gas Shales Project (EGSP) research consortium, the Pennsylvania Geological Survey established a basic subsurface stratigraphy of the Middle and Upper Devonian section organic-rich black shales in Pennsylvania using gamma-ray wireline logs. Since 2004, thousands of shale gas wells have been drilled in Pennsylvania, generating renewed interest in the lithostratigraphy, mineralogy, and thermal maturity of the Marcellus and other organic-rich shales. The modern downhole geophysical log data associated with these shale gas completions has facilitated a deeper dive into the lithostratigraphy of both the Marcellus Formation and shallower Middle and Upper Devonian shales. As part of Pennsylvania’s ongoing MRCSP research – namely, interpreting and mapping the lithostratigraphy of organic-rich shales for enhanced gas recovery potential using carbon dioxide – Pennsylvania is building on EGSP and subsequent work. Additional geophysical logs and related data for ~3,500 wells in 41 counties has been interpreted to resolve Devonian shale to the formation and/or member level.
In conjunction with this talk, the Pennsylvania Geological Survey prepared cross sectional images that have been posted on the MRCSP website. New cross sections showing the reinterpreted stratigraphy for the western and northern portions of Pennsylvania can be downloaded at the bottom of the MRCSP Regional Characterization Page
. MRCSP was recognized as a funding source for the study.