Risk zonation of the landslides in Tehran province using Fuzzy Model

The mountainous parts of Tehran province is located on the formations where are susceptible to landslides and if the landslide occurres in these areas, we will be facing the irreparable effects in various aspects. The purposes of this study are investigation and analysis of landslide in Tehran province and zonation of those areas where are susceptible to landslide. This zonation is done by using 8 quantitative and qualitative indicators, including geology, elevation, slope, aspect, distance from the faults, distance from the rivers, land use and average annual precipitation as the factors in the occurrence of landslide in ArcGIS software. The result of the present study showed that about 13.31 percent of the study area is located in high and very high zones of potential vulnerability, 13.71 percent of the study area is located in moderate zone of potential vulnerability, and about 72.94 percent is located in low and very low zones of potential vulnerability as well. After conducting field observations of landslide-prone areas and comparing it with the zonation map, accuracy and efficiency of fuzzy model will be verified. High and very high zones of potential vulnerability are mainly foothills and mountainous areas of Tehran Province. We considered high vulnerability due to topography and human factors. However, risk of landslides morphology seems to be a function of slope, indicating the role of slope in landslide occurrence.