GEOLOGIC MAPPING ALONG THE BLUESTONE RIVER AND THE NEW RIVER GORGE, SUMMERS AND MERCER COUNTIES, WEST VIRGINIA

The Geology Department at Concord University is mapping the Bluestone National Scenic River and the southern portion of New River Gorge. The New River flows from south to north, rising in the Smoky Mountains and cutting across the Great Valley and Valley and Ridge provinces before entering the Appalachian Plateau. Concord University is starting with the Pipestem and Flat Top quadrangles. Bedrock is low-dipping, Carboniferous sedimentary rock. The stratigraphic units are heterolithic, consisting of sandstones, shales, mudstones, paleosols, and thin limestones (both marine and freshwater). Strata are laterally discontinuous, requiring several different techniques for mapping. The primary technique is to identify the most distinctive, laterally continuous units across the region, locate those units, determine their elevation, and construct structure contour maps. Combining the structure contours with topographic maps produces a reasonable outcrop approximation that can be field checked. The two units selected for this process are the Avis Limestone (Little Stone Gap Member) of the Hinton Formation, and the Princeton Sandstone Member of the Bluestone Formation. The Avis is an argillaceous limestone 5-10 meters thick, easily recognizable amongst the red siliciclastics of the upper Hinton. With a recognizable marine fauna, the Avis is traceable into the Appalachian basin. The Princeton is a conglomeratic quartz arenite that produces a benches and plateaus. The Princeton was deposited in a paleovalley, varying its thickness from 0-20 meters. Throughout the first summer of field work most of the available outcrops have been located and cataloged and structure contours have been constructed. Because the strata are nearly-flat lying, and the New and Bluestone rivers have deeply incised the plateau, walking out all of the contacts is prohibitive. This technique provides us the opportunity to identify those areas requiring specialized and detailed attention.