Suggested Citation
Delano, H. L., and Wilshusen, J. P., 1999, Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Environmental Geology Report 9, 192 p. [Available online.]
Description
The report includes a text describing types of landslides and contributing factors, and a 1:250,000-scale map of the Williamsport 1- by 2-degree quadrangle in north-central Pennsylvania showing high-susceptibility, moderate-susceptibility, and low-susceptibility landslide zones. The study area includes major portions of the Deep Valleys, Glaciated High Plateau, and Glaciated Low Plateau sections of the Appalachian Plateaus physiographic province, and of the Appalachian Mountain section of the Ridge and Valley province. Bedrock ages range from Cambrian to Pennsylvanian, and approximately half of the area is covered by Wisconsinan glacial deposits. Most of the bedrock not covered by glacial deposits are covered by colluvial and residual soils. More than 1,300 recent and older landslides were surveyed to define the three susceptibility zones, and data on these slides are listed in a table in the appendix. Also in the appendix, the locations of the inventoried slides are shown on 1:62,500-scale, 7.5-minute quadrangle maps.