Landslide Hazard Modeling in Taleghan Watershed(Case study: Nomads area in Taleghan)

Landslides are crucial geomorphological hazards that cause much damage to natural resources, agriculture and construction activities and have many economic and social effects.

Purpose of the research: 

This research was conducted to identify the effective factors in creating landslides and determine the areas prone to landslides to prevent the occurrence of landslides using the LNRF method.

In this research, after collecting basic information, a digital elevation model (DEM) and topographic maps were used in order to create information layers of a slope, slope direction, and height, and after cutting the active maps with the distribution map of landslides, LNRF for Each map unit was calculated.

Geographical area of research:

 The study area of this research is Taleghan basin, one of the cities of Alborz Province, which is located 120 km northwest of Tehran.

At first, parameters such as slope, slope direction, height, distance from the fault, distance from the road, distance from the river, geology and land use as effective factors in the environment of geographic information systems (GIS) were prepared and digitized. Then the distribution map of landslides was then prepared using a geological map with a scale of 1:100,000, field visits, and a global positioning system. Using the relationships governing the model, the weight of each effective factor, which indicates their impact in causing landslides, has been calculated.

The results showed that the most influential variables in the occurrence and prediction of the risk of landslides are slope, slope direction, Neogene and Quaternary marls and the use of medium-density pastures. On the other hand, the zoning of landslide risk and the examination of very high-risk zones showed that about almost half of landslides occurred in 36% of the total area of the study area.