Ground Penetrating Radar Investigation of a Possible Sinkhole in Jefferson County, West Virginia

Abstract

Karst terrain landforms have been identified and mapped in Jefferson County, West Virginia. One of the more common surface features in the area, sinkholes are a geohazard that can create difficult conditions for local development. Shepherd University’s Tabler Farm is currently experiencing a period of expansion and growth of infrastructure. We conducted a ground penetrating radar (GPR) survey in an area suspected of being the surface expression of a sinkhole. The survey area covers roughly 430 m² and sits in a topographic depression. Using 1 m spacing between 10 transects, we surveyed 30 m long lines across the depression using a dual antenna, broad spectrum (250-700 MHz) GPR. Our data revealed numerous strong near surface reflections in the shallow channel radargrams. The study site has been used in the past to collect refuse and remains of metallic material were observed at the surface. While we removed observable metallic material from survey paths, the shallow reflectors are likely metal objects beneath the surface. Our data does display data integrity issues caused by the uneven and rough surface which prevented the antenna from keeping constant contact with the ground surface. Deep channel radargrams do reveal dipping horizons (2.4 m deep) at the southwest end of multiple survey lines, which may represent the edge of a sinkhole.