Characteristics of Clustering Debris Flows in Wenchuan Earthquake Zone  

作　　者：MA Chao HU Kai-heng ZOU Qiang TIAN Mi 

机构地区：[1]Key Laboratory of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences [2]Institute of Mountain Hazards and Environment, Chinese Academy of Sciences [3]Graduate school of Chinese Academy of Science

出　　处：《Journal of Mountain Science》2013年第6期953-961,共9页山地科学学报（英文）

基　　金：supported financially by the Key Research Program of Chinese Academy of Sciences (Grant No. KZZD-EW-05-01);the Knowledge Innovation Program of Chinese Academy of Sciences (Grant No. KZCX2-YW-JS305);the Hundred Young Talents Program of Institute of Mountain Hazards and Environment;National Natural Science Foundation of China (Grant No. 40701014)

摘　　要：Clustering debris-flow events, namely many debris flows simultaneously triggered by a regional rainstorm in a large-scale mountainous area,occurred in four regions of Wenchuan earthquake stricken areas in 2008 and 2010. The characteristics of the clustering debris flows are examined with regard to triggering rainfall, formation process, and relationship with the earthquake by field survey and remote sensing interpretation. It is found that the clustering events occurred nearly at the same time with the local peak rainstorms, and the rainfall intensity-duration bottom limit line for clustering debris flows is higher than the worldwide line. It means that more rainfall is needed for the occurrence of the clustering debris flows. Four kinds of major formation processes for these debris flows are summarized: tributary-dominated, mainstreamdominated, transformation from slope failures, and mobilization or liquefaction of landslide. The four regions has a spatial correlation with the strongquake-influenced zone with the peak ground acceleration = 0.2 g and the seismic intensity > X.

关 键 词：Clustering debris flows Wenchuanearthquake Rainfall threshold Formation process 

分 类 号：P642.23[天文地球—工程地质学]