汶川地震灾区崩塌滑坡体几何特征信息遥感定量提取与分析

选取灾区107个崩塌滑坡样本,利用遥感影像获取崩塌滑坡面积,遥感影像结合DEM获取崩塌滑坡体坡高(前后缘高差)、滑移距离、视摩擦角等信息,通过野外调查获取体积信息,对灾害评估中关注的两个关键因子崩塌滑坡体体积、滑移距离与各特征因子的相关性进行了分析,探讨了体积、滑移距离与相关性显著因子间的关系。研究表明,崩塌滑坡体体积与崩塌滑坡面积、坡高相关性显著,且与崩塌滑坡面积呈显著的幂函数关系,与坡高呈二次多项式关系,与滑移距离、视摩擦角有一定关系,但不显著;崩塌滑坡滑移距离与坡高相关性显著,且呈线性关系,与崩塌滑坡面积也有一定关系,但不十分显著。

Extracting and Analyzing Geometric Features of Landslides Induced by Wenchuan Earthquake Based on Remote Sensing

In this study,we selected 107 landslides in the earthquake-stricken area for investigation.The geometric features of the landslides were extracted based on remote sensing,DEM(digital elevation model) data and field survey.The area of the landslides was obtained by interpreting individual landslides from remote sensing images.The apparent friction angles,travel distances,and the heights of the landslide bodies were extracted from remote sensing images combined with DEM.The total volumes of the landslides were gained by field survey.Furthermore,we linked the total volumes and travel distance of the landslides with the other geometric features factors,such as the areas,apparent friction angles and heights.The results indicate that the total volumes had significant relationship with landslide areas and landslide heights,which could be described well by a power equation and a quadric polynomial equation,respectively,while the travel distances correlated significantly linearly with the landslide heights.However,the other relationship was not statistically significant.