AN APPALACHIAN BASIN NATURAL GAS CHEMISTRY DATABASE

The United States Geological Survey (USGS) has created an updated digital gas chemistry database for Paleozoic fossil-fuel bearing strata of the central Appalachian Basin. This database was originally a flat ASCII data file from the U.S. Bureau of Mines (USBM) containing 433 gas analyses published by the USBM between 1917 and 1992. These analyses were augmented by 51 gas analyses collected by the USGS, as well as an additional 529 USBM analyses, which were added to the digital database from published USBM reports.

The database contains descriptive data such as well numbers, state, county, lease holders, and locations, as well as analytical data for methane, ethane, propane, iso-butane, n-butane, nitrogen, oxygen, argon, hydrogen, carbon dioxide, and helium. These data were entered and verified from USBM reports. State American Petroleum Institute (API) numbers, and geographic locations (about 80% of the locations are accurate with about 20% of the locations assigned locations using centroids for the county, township, or tax district) were obtained from the following state sources: Ohio Geological Survey, West Virginia Geological and Economic Survey, Virginia Division of Mineral Resources, Kentucky Geological Survey, and Geologic Division of the Tennessee Department of Environment and Conservation. After subdividing the database into Ordovician, Silurian, Devonian, and Carboniferous periods, methane, nitrogen and carbon dioxide analytical values were mapped in a GIS for presentation to show temporal variation in gas chemistry.