Landslide Susceptibility Zonation With Special Emphasis on Tectonic Features for Occurrence of Landslides in Lower Indian Himalaya

Landslide susceptibility zonation (LSZ) map is prepared for a part of the lower Himalayas using the fuzzy cosine amplitude method. The prepared LSZ map is validated both statistically and physically, and it is found that around 30% of the study area lies in zones of high to very high landslide susceptibility. To correlate the Himalayan seismicity with the landslide hazard, the prepared LSZ map is further assessed in terms of the impact of fault distance on the occurrence and spatial distribution of landslides in the study area. The results quantify a strong inverse correlation between fault distance and the probability of landslide occurrence. A high coefficient of determination (R2 = 0.986) indicates that the equation can realistically predict the impact of fault distance on the study area's landslide occurrence. Further, landslide relative frequency (LRF) method is used to evaluate the statistical contribution of fault distance toward overall landslide susceptibility for the study area. It is found that distance from any major tectonic feature is a significant landslide causative parameter, with a relative importance of 21%. The prepared LSZ map will be valuable for decision-makers during smart town planning and sustainable development in the study area.