This layer is a deep landslide susceptibility map. The symbology on this map includes high and moderate susceptibility zones. The deep susceptibility zones were established based upon location and proximity to deep landslide deposits and head scarps, buffers along the landslide head scarps, susceptible geologic units, slope angles, and mapper judgement following protocol developed by Burns (2008).
A landslide inventory database was prepared by following the Protocol for Inventory Mapping of Landslide Deposits from Light Detection and Ranging (lidar) Imagery developed by Burns and Madin (2009). Using the lidar-based landslide inventory and several other data sets, a deep landslide (failure depth greater than 15 ft [4.5 m]) susceptibility map was created following a method developed by Burns and Mickelson (2016). Deep-landslide susceptibility zones were established from locations and proximity to deep-landslide deposits and head scarps, head scarp buffers, susceptible geologic units, slope angles, and mapper judgment. This map cannot serve as a substitute for site-specific investigations by qualified practitioners. Site-specific data may give results that differ from those shown on this map. The recommended map scale for this data is 1:8,000 as displayed on this map.