| This study was designed to analyze the perplexing Carboniferous stratigraphy in the study area using a sequence-stratigraphic approach in conjunction with lithostratigraphic and subsurface mapping methods.; A regional stratigraphic framework is established for the uppermost Devonian to Middle Pennsylvanian interval in the study area using a network of well-log cross sections. Lithostratigraphic units are correlated throughout the study area mostly at formation level; most of the units are correlated from the subsurface to their outcropping equivalents.; Four sequences are identified within the study interval, based on the recognition of sequence-bounding unconformities, condensed sections and stacking patterns.; The sub-Ravencliff unconformity is recognized by this subsurface study as a regional angular unconformity within the Mauch Chunk Group. Of the five sequence-bounding unconformities, the sub-Ravencliff and sub-New River unconformities were probably related to loading relaxation, whereas the sub-Berea, sub-Greenbrier, and sub-“Mahoning” unconformities likely resulted from post-orogenic rebound in terms of flexural foreland-basin models.; From the latest Mississippian to Early Pennsylvanian, the study area experienced significant change in drainage pattern. The drainage systems of stage 1 (at Mississippian-Pennsylvanian transition) in the study area flowed mostly northwestward, whereas those of stage 2 (Early Pennsylvanian) flowed southward and southwestward.; The incised-valley systems along the sub-Ravencliff and sub-New River unconformities are analyzed with detailed cross sections and isopach maps. Generally, the paleovalleys were filled first with quartz-rich fluvial sands during stillstand and the following transgression, and then mostly with clays as marine influence increased.; Basement reactivation profoundly influenced the depositional thickness, lithofacies, subaerial erosion, drainage system, and structural development during the Carboniferous. The occurrences of the Burning-Mann, Summersville and Beckley faults are suggested by stratigraphic evidence from this study. A buried anticline, the Gauley Mountain, is delineated within the Upper Mississippian interval with evidence from cross sections and isopach maps.; Finally, Carboniferous basin history of the central Appalachian foreland basin is summarized in terms of intra-basinal basement reactivation, change in regional tectonic regime, migration of basin center and depocenter, and shift of source area and paleocurrent direction. |
