A multidisciplinary approach of landslide characterization: A case of the Siwalik zone of Nepal Himalaya

Abstract

The landslide is a common problem in the Siwalik zone of Nepal Himalaya during the monsoon period. The heterogeneity of lithology comprising of thickly bedded sandstone and mudstone, weakly cemented conglomerate beds, and permeable quaternary deposits on moderate to steep slopes are primarily responsible for the landslide in this zone. In this study, a multidisciplinary approach is used for the landslide characterization. The polygon-based landslide inventory map was prepared by using Sentinel-2, Landsat-8, and Google Earth imageries. The draft inventory map was verified and updated by several field visits. The final inventory map was overlaid with topographical, geological, and hydrological maps in Q-GIS and explored the landslide characteristics. Landslide distribution to geological units, thrust zone, slope, aspect, and rainfall amount along with the geotechnical properties are manifested and the relation between each selected factor is discussed. The study shows that a multidisciplinary technique provides the better option for landslide characterization.