Identification of potential rockfall source areas at a regional scale using a DEM-based geomorphometric analysis

摘要: Abstract. The availability of high resolution Digital Elevation Models (DEM) at a regional scale enables the analysis topography with levels detail. Hence, DEM-based geomorphometric approach becomes more accurate for detecting potential rockfall sources. Potential source areas are identified according to slope angle distribution deduced from DEM crossed other information extracted geological and topographic maps in GIS format. can be decomposed several Gaussian distributions that considered as characteristic morphological units: rock cliffs, steep slopes, footslopes plains. A terrain is sources when their angles lie over an threshold, which defined where unit "Rock cliffs" become dominant one "Steep slopes". In addition this analysis, cliff outcrops indicated by were added. They contain however "flat areas", so only values above mode slopes" considered. An application method presented entire Canton Vaud (3200 km2), Switzerland. results compared observed on field orthophotos order validate method. Finally, influence cell size inspected applying methodology six different resolutions.