Landslide susceptibility analysis of Karakoram highway using analytical hierarchy process and scoops 3D

Abstract

Landslides are prevalent, regular, and expensive hazards in the Karakoram Highway (KKH) region. The KKH connects Pakistan with China in the present China-Pakistan Economic Corridor (CPEC) context. This region has not only immense economic importance but also ecological significance. The purpose of the study was to map the landslide-prone areas along KKH using two different techniques-Analytical Hierarchy Process (AHP) and Scoops 3D model. The causative parameters for running AHP include the lithology, presence of thrust, land use land cover, precipitation, and Digital Elevation Model (DEM) derived variables (slope, curvature, aspect, and elevation). The AHP derived final landslide susceptibility map was classified into four zones, i.e., low, moderate, high, and extremely high. Over 80% of the study area falls under the moderate (43%) and high (40%) landslide susceptible zones. To assess the slope stability of the study area, the Scoops 3D model was used by integrating with the earthquake loading data. The results of the limit equilibrium analysis categorized the area into four groups (low, moderate, high, and extremely high mass) of slope failure. The areas around Main Mantle Thrust (MMT) including Dubair, Jijal, and Kohistan regions, had high volumes of potential slope failures. The results from AHP and Scoops 3D techniques were validated with the landslides inventory record of the Geological Survey of Pakistan and Google Earth. The results from both the techniques showed similar output that coincides with the known landslides areas. However, Scoops 3D provides not only susceptible zones but also the range of volume of the potential slope failures. Further, these techniques could be used in other mountainous areas, which could help in the landslide mitigation measures.