Natural Hazards and Earth System Science www.nat-hazards-earth-syst-sci.net 1561-8633 1684-9981 10 2 2010 10.5194/nhess-10-159-2010 http://www.nat-hazards-earth-syst-sci.net/10/159/2010/ http://www.nat-hazards-earth-syst-sci.net/10/159/2010/nhess-10-159-2010.html http://www.nat-hazards-earth-syst-sci.net/10/159/2010/nhess-10-159-2010.pdf 159 170 2010-02-01 A simple qualitative approach for mapping regional landslide susceptibility in the Faroe Islands M.-P. J. Dahl mpjd@ruc.dk L. E. Mortensen A. Veihe N. H. Jensen Department of Environmental, Social and Spatial Change, Roskilde University, Universitetsvej 1, P.O. Box 260, 4000 Roskilde, Denmark Jarðfeingi (Faroese Earth and Energy Directorate), Brekkutun 1, 0110 Tórshavn, Faroe Islands The Faroe Islands in the North Atlantic Ocean are highly susceptible to landslides. Following recent landslide incidents, Jarðfeingi (Faroese Earth and Energy Directorate) has pointed out, that the risk of human lives or of property being lost or affected by landslides may be increasing. This paper aims at presenting and testing a simple qualitative approach for mapping regional landslide susceptibility in the Faroe Islands, using few key parameters. The susceptibility model holds information about both landslide initiation areas and runout zones. Landslide initiation areas are determined from slope angle thresholds (25°–40°) and soil cover data, while runout zones are delineated using the angle of reach approach taking into account the presence/absence of geological benches in the runout path, which has not been considered in earlier studies. Data input is obtained from a landslide database containing 67 debris flows throughout the Faroe Islands. Angle of reach values differ significantly with the presence/absence of geological benches in the runout path. 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