ONGOING RESEARCH ON SLOPE STABILITY IN UPSTATE SOUTH CAROLINA: FIELD OBSERVATIONS, LINEAMENT STUDIES, AND LANDSLIDE MODELING

Understanding slope stability along the Blue Ridge escarpment in northwestern South Carolina is important in a region of high recreational activity and which is also under pressure for development. Ongoing research by undergraduate students and faculty has included field observations and mapping of recent and older mass movement events; collection and analysis of climatic data; automated digital mapping of lineaments; and modeling of slope stability and landslide susceptibility using GIS. Field observations reveal the importance of geologic and geomorphic factors including steep slopes, low permeability gneissic bedrock, well-developed exfoliation surfaces, poor soil formation, and prominent joint sets. Climate data show a strong link between exceptional rain events and historic mass movements in the study area. Automatically extracted and field-mapped lineaments for the study area show a strong correlation with the regional drainage pattern, which in turn affects slope evolution and stability. GIS modeling has identified high- and medium-hazard zones for the Mountain Bridge Wilderness area, a small segment of the Blue Ridge escarpment in Greenville County, but this work and lineament extraction needs to be expanded along the length of the escarpment. High-resolution, LIDAR-based elevation data, now becoming available to Upstate counties, will make detailed topographic analysis and historical landslide identification possible for the whole region. Continued field verification and integration of the data on lineament orientation are necessary to test and improve GIS-based modeling of landslide hazards.