Assessment of Landslides Susceptibility in Giri Watershed, Northwest Himalaya, Himachal Pradesh, India

Abstract

The slope instability in the Himalayan terrain is a common phenomenon which is caused by a combination of the ongoing seismicity and climate variability (extreme weather evets). In addition to this, in the last few decades, the anthropogenic intervention in the form of various developmental activity (roads, hydropower projects, expansion of urban sectors etc.) have posed serious threat to slope stability. In this study we have evaluated the terrain status for landslide susceptibility in a monsoon fed Giri Watershed. An attempted has been made to decouple various causative factors of landslides susceptibility of the region using remote sensing and GIS techniques. Employing the Frequency ratio and the information value methods, the study observe that increasing incidences of landslides occur along the drainage in the lower valley sides, along the linear developmental activities and settlement areas. Further the study observed a broad correlation between rock formation, lineaments, vegetation types, and slope steepness.