Paleoenvironmental reconstruction of the Upper Mississippian Reynolds Limestone in the Central Appalachian Basin of West Virginia

The Upper Mississippian strata in West Virginia, southern Pennsylvania, and western Maryland are predominantly composed of interbedded limestones and shales. The focus of this study, the Reynolds Limestone, is a formal member of the lower part of the Bluefield Formation, in the Mauch Chunk Group, of the Chesterian Series.;This research addresses fades changes in terms of sea level fluctuations and basinal settings during the deposition of the Reynolds Limestone. Specifically, this research consists of the measurement and description of the seven field localities and thin section analysis of carbonate units within the identified study interval.;Primary objectives were to determine the depositional history of the Reynolds Limestone based on the paleoecology and stratigraphy of the strata. These objectives were achieved through detailed outcrop measurement and thin section analysis of carbonate units.;Results indicate the Reynolds Limestone was deposited during several, small-scale transgressive/regressive events. The Reynolds is regionally correlative to the Glen Dean Limestone of the Illinois Basin. This correlation suggests that large-scale glacial effects were controlling eustatic sea level fluctuations in the Late Mississippian. An early onset glacial event is recorded by the Lillydale Shale and an interglacial period by the Reynolds Limestone. The data show structural controls played an important role in the deposition of the strata in the Reynolds interval but not on sea level fluctuations. In southern West Virginia, there is a significant thickening of strata resulting from filling of a rapidly subsiding basin. It has been determined based on the paleoshoreline orientation and its relation to sea level fluctuations, that the Reynolds Limestone can be considered a time correlative unit. (Abstract shortened by UMI.)