Rock fall Hazard and Risk Assessment Using GIS Along Jaglot-Skardu Road, Pakistan

Rockfall is one of the major hazards all around the world. In Northern Pakistan, Jaglot-Skardu. The road is the main highway that connects KKH and Skardu, located in Gilgit Baltistan. The Area isvery unique to study rockfalls because of the variety of changesin the geological, seismological, and atmospheric conditions. The hazard and risk mapping of rockfalls includes preparation of rockfall inventory map,susceptibility map and spatial analysis of Rockfall with its conditioning factors using GISand Remote Sensing. The inventory map includes record of past rockfalls along the road and prepared on hill shade map of the area using ArcGIS 10.4. Susceptibility maps of the area is generated using Weighted overlay technique. In Weighted overlay technique we use multi influencing factors of the rockfalls as such as aspect, geology, slope, elevation, faults, curvature, Topographic wetness index, streams and road. Each map unit is than reclassified and assigned weight in weighted overlay to generate susceptibility map of area. In inventory map, almost 200 rockfalls are marked and delineated on hill shade map of the area. The results of susceptibility show four zones i.e., low, moderate, high and very high hazard zones.The spatial analysis of rockfalls showed that fault and geology is the main factor that are triggering the rockfalls in the area. The areas which are present low and moderate susceptible zones are somehow safe and suitable for future planning and development and areas present in high to very high susceptible zones, large scale geotechnical investigations are required before any development and construction.