A GIS application for assessing landslide hazard over a large area

A sophisticated GIS application for assessing landslide hazard on a large scale is presented. In order to assess the landslide hazard, the critical natural slope in a small field of study, 200 m × 200 m, is found and the slope is analysed using a non-circular failure envelope with estimated soil properties, groundwater levels, earthquake, and surcharged loadings. The analysis uses a probabilistic approach, where groundwater, earthquake and soil properties each contribute to the analysis, even though some factors may have a relatively small influence. Landslide hazard can then be estimated within a period of time by analysing the probabilistic distribution of factor of safety.