LANDSLIDE SUSCEPTIBILITY ASSESSMENT FOR ILAM PROVINCE IN IRAN, BY USING MCDM AND GIS TECHNIQUES

Landslides are one of the well-known geological hazards that responsible for extensive damages for infrastructures, roads, facilities, and interference in the general social life of humans. To avoid such catastrophic destructions, the landslide susceptibility assessment must be done. The presented study attempted to provide a landslide susceptibility analysis for Ilam province located in western part of Iran. After a comprehensive field and remote-sensing investigations, fifteen landslide triggering factors are detected for this study which classified as geomorphology, geological, climatological, seismical, and human works major groups. Multi-Criteria Decision-Making (MCDM) model used to rank the triggering factors were prepared to enter in the Geographical Information System (GIS) environment. Totally 10 historical landslides that extracted from literatures was used as ground validation for susceptibility assessments. The results of the susceptibility mapping are categorised into five susceptibility class included very low (12.5%), low (19.21%), moderate (25.49%), high (27.27%), and very high (15.53%). According to the results of the susceptibility assessment for the studied region, it appeared that the most area is in moderate to high risk regarding landslides occurrence. But the northwest part of the province is located in very high-risk zone. So, considering the results, decision-makers should conduct relevant investigations on landslide before planning or developments in high-risk areas at Ilam province.