GIS BASED LANDSLIDE SUSCEPTIBLITY MAPPING FROM THAKOT TO DASSU KARAKORUM HIGHWAY, KHYBER PAKHTUNKHWA, PAKISTAN

Abstract

The main objective of the study is to prepare landslide susceptibility map of 90 km section of Karakorum Highway, from Thakot to Dassu, Khyber Pakhtunkhwa, Pakistan. Study area is situated in Karakorum mountainous region where catastrophic landslides occur frequently and pose a serious threat to local living conditions and one of the major trade route of Pakistan and China. This study presents the use of geographical information system (GIS) datasets and methods to investigate landslide susceptibility in the mountainous terrain of Kohistan, Battagram and Shangla districts of Khyber-Pakhtunkhwa, Pakistan. Landslide susceptibility index map was prepared by combining nine parameters (slope, aspect, plane curvature, elevation, land cover, distance from road, lithology, distance from faults, and distance from drainage). The layers for these parameters were prepared in ArcGIS using weighted overlay method (WOM) and analytical hierarchy process (AHP). Four different susceptibility zones have been identified in the region. AHP weights with 0.15 consistency ratio were used in the preparation of final map. The final landslide susceptibility map of 90 km road section with 2.5km buffer of each side from road, indicated the low, moderate, high and very high susceptibility classes covering 1% (5.20 km2), 39% (182.69 km2), 50% (235.31 km2), and 10% (47.86 km2) area respectively. Final map is verified using landslide history acquire from Google imagery and literature.