基于GIS的概率比率模型的滑坡易发性评价

以中国1∶50万区域环境地质调查(以地质灾害为主)、700个县(市)地质灾害调查与区划调查等(成果)资料为基础,选取地形起伏度、地貌类型、工程地质岩组、地震动峰值加速度、年平均降雨量、土地利用程度综合指数6个评价因子,采用概率比率模型,1 km×1 km评价单元,计算得到全国滑坡易发性评价指数图,并验证了结果的可靠性。进行了易发程度分区,最终得到高易发区、中易发区、低易发区和不易发区4个分区,完成了全国滑坡易发程度分区图。研究表明,概率比率模型方法可以客观、定量地评价滑坡易发性,适用于大区域易发性评价。

Landslide susceptibility assessment by probability ratio model based on GIS

On the basis of the 1∶500000 regional environgeology survey in China with emphasis on geological hazards and the geological hazard and regionalization investigation conducted in 700 counties/cities nationwide,we utilized the 1 km×1 km probability ratio model to deliver the Landslide Proneness Exponent Diagram of China with 6 evaluation factors including terrain roughness,geomorphy,engineering geological petrofabric,seismic motion,climate and land-use types.According to landslide susceptibilities,the high-,medium-,low-and no-risk zones are delineated and shown in the resultant China Landslide Proneness Zoning Map.The result reliabilities have been examined in this study,which indicates that the probability ratio model is effective in evaluating the large-scale landslide proneness quantitatively and objectively.