Zakieh Safarpour; Jalil Farzadmehr; Ali Golkarian; Mahdi Bashiri
Abstract
Landslide is one of significant mass movement which causes normous annual human and sesmic region. Therefore, finding hazardous areas for planning and management of them is necessary. So, in this reasearch, occurred landslide in watershed region of bidvaz dam which has area of 161 square kilometers and ...
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Landslide is one of significant mass movement which causes normous annual human and sesmic region. Therefore, finding hazardous areas for planning and management of them is necessary. So, in this reasearch, occurred landslide in watershed region of bidvaz dam which has area of 161 square kilometers and 125 landsliding points are surveyed in different hydrological conditions by index model of slope stability. For specified slopes, graiding test was done and geotechnical parameters were attained. Then, by using Arc view and Arc GIS packages and calibrating parameters in SINMAP and incorporating the geotechnical and hydrological parameters with digital elevation model, SINMAP was conducted. After that, validation was done in two common and high hydrological conditions including rainfalls with a return period of 2-10 years and 20-50 years Respectively. Results showed that the performance of model in simulation of landslides is not appropriate at common hydrological cases. However, increase in hudrological humidity condition, performance of model improves. In calibration and validation, prediction of model increase 21 % and 26 %, respectively. Therefore, utilizing SINMAP model in high hydrological humidity conditions can be useful for choosing dangerous ways according to the landslide map.
Asghar Kouhpeima; Sadat Feiznia
Abstract
Landslide causes many social and economic losses in many parts of the world every year. These losses can be greatly reduced by using appropriate management measures such as mapping landslide susceptibility mapping in the basin. The aim of this study is landslide susceptibility mapping using Mahalanobis ...
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Landslide causes many social and economic losses in many parts of the world every year. These losses can be greatly reduced by using appropriate management measures such as mapping landslide susceptibility mapping in the basin. The aim of this study is landslide susceptibility mapping using Mahalanobis distance in the Latyan catchment. First, a total of 208 cases of landslides identificated and geo-referenced using geographic information systems based on an interpretation of aerial photographs and extensive field surveys and provided a landslide inventory map. The map of 12 factors, including rainfall, land use, distance to fault, distance from river, distance from road, lithology, altitude, slope, aspect, plan curvature, Peak Ground Acceleration and topographic wetness index as the most important factors in landslides was prepared. Then the correlating each factor and the landslide was examined. Finally landslide susceptibility zoning map was provided based on the Mahalanobis distance in Latyan catchment. To evaluate the results, the ROC and chi-square tests were used. The results show more than 80 % of the catchment located in range of high and very high susceptibility classes and need to suitable management operations. AUC index (area under the curve ROC) for this model is achieved to 0.896 or 89.6% which represent capability and high accuracy. Chi-square test results also reflect the proper separation of landslide susceptibility classes by model.
Ommolbanin Kazemi Gordgi; Hasan Ahmadi; Mohammad Jafari
Abstract
The ultimate aim of any research on the mass movement processes is to prepare zonation map and classify area into different degrees of hazard in order to mitigating related damages. This study was undertaken using F-AHP & GIS within Nekaroud watershed in Mazandaran province. Pairwise comparisons ...
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The ultimate aim of any research on the mass movement processes is to prepare zonation map and classify area into different degrees of hazard in order to mitigating related damages. This study was undertaken using F-AHP & GIS within Nekaroud watershed in Mazandaran province. Pairwise comparisons showed that sub-criteria’s Slope (>30%), elevation (> 1700 m), distance from fault (0-200 meter), distance from river, residual land-use and precipitation (>600 mm) have high weight than others in their group which lead to increasing occurrence of landslides. In the study area much amount of lime stone was found which is effective in reducing landslide. Major parts of central areas of watershed are prone to the most dangerous and high frequency landslides, other parts of watershed classified into medium and a little part is in low danger class.
