Geomorphology
somayyeh moazzez; Davoud Mokhtari; Mohammad hossein Rezai Moghadam
Abstract
AbstractAlluvial fans are among the areas prone to geomorphological hazards. One of these hazards is liquefaction, which the main purpose of this research was to investigate this phenomenon in the surface of the alluvial fan. The FUZZY-VIKOR combined model and GIS technique were used to prepare the liquefaction ...
Read More
AbstractAlluvial fans are among the areas prone to geomorphological hazards. One of these hazards is liquefaction, which the main purpose of this research was to investigate this phenomenon in the surface of the alluvial fan. The FUZZY-VIKOR combined model and GIS technique were used to prepare the liquefaction risk potential map. The used parameters in this research were: slope, depth of underground water, type of soil and seismicity. The information layers of each of these parameters were prepared in the ArcGIS software environment. Next, the fuzzy model was used to standardize the layers. At the end, the weighting of the parameters was done by Vikor method. . The results of weighting the parameters by Vikor method showed soil and depth of underground water have obtained the highest importance coefficient with the weight of 0.442 and 0.236 respectively. The final map was prepared by overlapping the layers and multiplying the final weight of the criteria in each layer in 5 classes from very low to very high potential. The final map was prepared by overlapping the layers and multiplying the final weight of the criteria in each layer in 5 classes from very low to very high potential. The results of examining the area of each risk class showed that 0.28% of the area is in the very high class and 70% is in the high class in terms of the risk of liquefaction. Mainly, the areas with high risk potential are located in the downstream parts of the region.
sayedeh masumeh mousavi; Mohammad Hossein Rezaei Moghaddam; Masumeh rajabi
Abstract
Landslides claim the lives of thousands of people around the world each year, causing enormous damage to people and governments. Landslide risk zoning divides landslides into specific and distinct areas of potential and actual degrees in terms of risk, this process is based on recognizing the qualitative ...
Read More
Landslides claim the lives of thousands of people around the world each year, causing enormous damage to people and governments. Landslide risk zoning divides landslides into specific and distinct areas of potential and actual degrees in terms of risk, this process is based on recognizing the qualitative characteristics of the area and quantitative modeling based on the data of the study area. This can be the basis for long-term planning at the regional and local levels.The purpose of this study is to investigate and zoning landslide risk in the Yellow River Basin located in the east of Khuzestan province using fuzzy logic method; For this purpose, first through field visits, geological maps and topography and by reviewing previous sources and reviewing the conditions of the region; Nine factors: elevation, slope, direction of slope, distance from fault, distance from river, distance from road, precipitation, lithology and land use were considered and selected as effective factors on landslide occurrence. Landslide hazard zoning maps were prepared using fuzzy gamma operator with values of 0.7, 0.8, 0.9. Then, the obtained maps were classified into 5 classes: very high, high, medium, low and very low.The results of the qualitative sum showed that the 0.9 fuzzy gamma operator is more suitable than other fuzzy operators. The results of the classified maps showed that 21.56% of the area in the high-risk zone and 43.24% of the area The area is located in a low risk zone.
