汶川地震前后崩塌和滑坡分布特征与敏感性对比分析

以汶川地震活动断裂龙门山断裂带穿过的12个县(市)为研究区,分析了研究区汶川地震前后崩塌和滑坡空间分布特征,并使用统计学方法Logistic回归模型分别对震前震后的崩塌和滑坡敏感性进行评价,结合崩塌和滑坡敏感性变化矩阵,分析了汶川地震后崩塌和滑坡敏感性的空间变化特征。震前崩塌和滑坡高敏感区主要沿河谷分布,而震后崩塌和滑坡高敏感区主要沿龙门山断裂带分布。震前的极高敏感区震后仍表现为极高敏感区,而靠近断裂带的区域,震前的低敏感区转换为高敏感和极高敏感区。

Comparison of Landslide Distribution and Susceptibility Before and After the Wenchuan Earthquake

The distribution of landslides in the twelve counties where Longmenshan faults pass through was investigated before and after Wenchuan earthquake.Then,the logistic regressive model was utilized to assess the landslide susceptibility before and after the earthquake.Based on the susceptibility mapping and transformation matrix,the susceptibilities showed a significant spatial variation before and after the earthquake.The high susceptible zones for landslides were located along river valleys before the earthquake,while primarily along the Longmenshan faults after the earthquake.The extreme high susceptible zones did not change.The areas with low susceptibility near the Longmenshan faults turned into high susceptibility level after the earthquake.