基于大型古滑坡的古地震历史重建和古地震参数反演

古地震对于区域或场地地震危险性评价具有重要意义，古地震滑坡作为古地震的重要标志，直接反应着震级和震中距这两项古地震参数。然而，目前基于古滑坡进行古地震参数反演的系统研究十分缺乏。本项目拟以四川省雷波县马湖区域四个古滑坡作为研究对象，采用滑坡学、地质年代学、工程地质学和岩土工程等多学科交叉的方法，构建一套由古滑坡反演古地震的系统方法，同时定量推定金沙江中下游地区古地震数据。重点开展：（1）基于滑坡地质图和现地形，建立一种恢复滑坡原始地形的方法；（2）采用36Cl宇宙核素测年方法，获取滑坡的可靠年代；（3）提出一套合理的古滑坡滑动面参数确定方法，进行滑坡失稳地震加速度计算；（4）建立基于多个古滑坡地震加速度融合的古地震参数系统反演方法。通过研究，可为区域或场地地震危险性评价提供古地震参数，为现代大型工程的设计烈度选定提供参考。

As an important symbol of paleoearthquake, the paleoearthquake landslides can be used to reckon the earthquake magnitude and the epicentral distance, which has great significance for regional or site seismic hazard assessment. But the systematic research of paleoearthquake parameters based on the ancient landslides is scanty at the moment. This research plans to study these four landslides in Mahu region, Leibo County, Sichuan Province and multidisciplinary methods with Landslide Science, Geochronology, Engineering Geology and Geotechnical Engineer is used. The research contents mainly include: (i) establish a method for restoring the original landform based on the geological map of landslide and the present terrain; (ii) achieve reliable age of each landslide with 36Cl cosmic radionuclide dating method; (iii) propose a set of reasonable method for determining the sliding surface parameters of ancient landslides for calculation of earthquake acceleration for landslide instability; (iv) establish a system inversion method of paleoearthquake parameters based on seismic acceleration of multiple ancient landslides. Through the research, paleoearthquake parameters can be provided for regional or site seismic hazard assessment, and also providing reference for the selection of the design intensity of modern large scale engineering.