Under a contract with the Gas Research Institute, the West Virginia Geological and Economic Survey has begun a two-year project to determine the relationship between Devonian shale production and certain geologic and technical factors, such as geologic structure. Six counties in western West Virginia were selected for study. The north-south-trending Burning Springs anticline bisects those counties and marks the western edge of the Salina salt basin. Two horizons were selected for structural datums--the base of the Huron Shale Member of the Ohio Shale (Upper Devonian), and the base of the Mississippian Greenbrier Group. Point-to-point contouring methods, rather than generalization, revealed deformation containing differing structural styles (domains) throughout the study a ea, and those domains may have a relationship to the Salina salt basin (Late Silurian).

Structural cross sections reveal that the southern end of the Burning Springs anticline is a gentle fold amplified by thrust faults, probably ramping up from a sole fault in the Salina salt beds. Mississippian, Pennsylvanian, and Permian strata are draped over those thrusts. Lineaments, as defined by structure contours, mark the boundaries of subthrust sheets along the Burning Springs anticline. Orientations of those structural lineaments coincide with orientations of mapped surface lineaments.

Oil production from the Devonian shales is confined to the eastern flank of the Burning Springs anticline in areas overlying the Salina salt basin, and may be related to fracturing caused by intense deformation, in contrast to less intense deformation of rocks west of the salt basin.

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