The Huron Shale Member is the major Devonian shale producing zone in all counties under study. To the north and east, the organic shales of the Huron are replaced by inorganic shales and siltstones; gas production in these areas probably comes from the entire shale interval. Gas-producting potential of the Rhinestreet has not been fully exploited despite its similar lithologic character to the Huron. Structure maps on the top of the Berea and vase of the Huron show two northeast-to-southwest trending synclines in Cabell and Wayne Counties, and a north-south anticline in Cabell County. Berea and Onondaga structure reveal benches at both levels in Jackson, Mason, and Putnam Countries, possibly indicating continued effects of normal faulting throughout the shale interval. The Huron and Rhinestreet Members display the largest ratio of shows to penetrations in Devonian shale wells in southwestern West Virginia, confiming the role of the Huron in total shale gas production, and emphasizing the potential of the deeper Rhinestreet Member. Smoothed maps of initial potentials are appropriate in the study of regional trends, but unreliable for precise estimation of gas volumes at individual locations. Maps of initial potentials show sets of linearities parallel and perpendicular to regional structural trends. These linearities implicate fractures as a control on gas volumes. The probability of success maps show two types of areas with production potential: sparsely-drilled areas with a high proportion of successful wells, and densely-drilled areas with intermingled successful and unsuccessful wells.