BASINWIDE COOPERATIVE STUDIES OF THE GAS POTENTIAL OF THE NEW ALBANY SHALE (DEVONIAN-MISSISSIPPIAN) IN THE ILLINOIS BASIN

Organic-rich shales, which are equivalent in age (Devonian-Mississippian) to the New Albany Shale of the Illinois Basin, are widespread in the United States and are major petroleum source rocks. In the Illinois Basin, the New Albany Shale was recognized as early as 1837 at which time David Dale Owen noted the occurrence of “[an] important stratum, --the black bituminous aluminous slate, which is to be seen … at the New Albany Ferry boat landing.”

Subsequent to Owen’s 1837 reconnaissance of Indiana, numerous geologic studies of the New Albany Shale were conducted in Illinois, Indiana, and Kentucky; however, many of the early studies were provincial and focused on shale exposures along the basin perimeter. In 1976 during the Eastern Gas Shales Project sponsored by the U.S. Department of Energy, a more cooperative basinwide research approach was applied to the New Albany Shale. From 1976 to 1979, the state geological surveys of Illinois, Indiana, and Kentucky investigated the stratigraphy, structural geology, mineralogy, and geochemistry of the shale. While each state produced its own maps and final report, the surveys did work together to begin the standardization of stratigraphic units and nomenclature across state boundaries and to contribute to a final report containing basinwide maps.

In 1990, soon after the creation of the Illinois Basin Consortium (IBC), the Illinois, Indiana, and Kentucky geological surveys began a cooperative project with the Gas Research Institute (GRI), now the Gas Technology Institute, to update and reinterpret pertinent data from the 1870s to 1991 to better assess the gas potential of the New Albany Shale. A report, a plate of basinwide cross sections, and basinwide maps (scale 1:1,000,000) of major structural features, core locations, elevation of the top of the New Albany Shale, total thickness of the shale, average initial potential for gas fields producing from the formation, and mean random vitrinite reflectance for New Albany Shale samples were completed in 1994.

In 1998, another IBC cooperative project was initiated with GRI to convert the 1994 paper basinwide maps to a digital GIS format and the 1994 cross section plate and report to a PDF format on CD-ROM. The database for the digital maps was also updated to include new wells drilled to/through the New Albany Shale from 1991 to 1997.