Geologic Overview, Coal Resources, and Potential Methane Recovery from Coalbeds of the Central Appalachian Basin—Maryland, West Virginia, Virginia, Kentucky, and Tennessee

Abstract

The Central Appalachian Basin occupies an estimated 22,850 sq mi over parts of Maryland, West Virginia, Virginia, Kentucky, and Tennessee. The Mississippian and Pennsylvanian strata that underlie the basin contain numerous coalbeds that have generated significant amounts of methane. Data for analyzing and estimating this resource were obtained from desorption data published by Diamond and Levine (1981); gas data from the USGS/R-9 well in Clay County, Kentucky; data from the horizontal borehole project at Island Creek Coal Company's Virginia Pocahontas No. 5 mine; and the Clinchfield Coal Company's Jawbone coalbed methane drainage project. Mine methane emission studies published by MSHA have been investigated, and these data have indicated that the coalbeds--especially the Pocahontas No. 3 and No. 4 coals--emit substantial quantities of methane. The Beckley mine in Raleigh County, Virginia, was monitored in 1974 to measure methane emission rates during mining. The methane potential of this area has been estimated from the published gas content information, related projects, mine emission data, and methane-related incidents. It has been estimated that the basin contains a potential in-place methane resource ranging from a low of 10 to a high of 48 trillion cubic feet. A coalbed methane primary target area for the Central Appalachian Basin has been defined over an area of southwest Virginia, eastern Kentucky, and southeast West Virginia. This area contains the highest measured coalbed gas content values, and other available project data suggest this area contains exceedingly high amounts of methane.