四川石亭江流域汶川地震滑坡崩塌分布及控制因素分析

＂5.12＂汶川大地震引发了石亭江流域严重的滑坡、崩塌,沿江两岸红白镇、金花镇及上游矿区的滑坡、崩塌掩埋了公路、水电站,摧毁铁路并堰塞石亭江,造成了大量的人员伤亡及财产损失。震后在中国地调局的资助下,进行了1∶5万野外地震次生灾害详细调查。研究结果表明,石亭江流域滑坡、崩塌分布在空间上具有明显的不均一性,即由石亭江下游至上游,总体呈加重趋势,而且沿山前断裂和中央断裂灾害异常发育,后者强于前者;地质灾害发育除受发震断裂控制外,还受地貌、岩性和人类工程活动等多因素控制,上述控制因素的耦合是导致石亭江地区地震地质灾害空间分布不均一的主要原因。

Distribution and Control Factors Analysis of Wenchuan Earthquake-caused Landslide and Collapse in Shiting River Basin of Sichuan Province

During ＂5.12＂ Wenchuan earthquake,serious landslide and collapse broke out in Shiting River Basin.Landslides and collapses blocked Shiting River at once in Hongbai Town,Jinhua Town and the mine region in the upstream,causing serious loss of people lives and property.Under the support of China Geological Survey Bureau,the 1：50000 detailed geological hazard survey of aftershock shows that the distribution of earthquake hazards is inhomogeneous in space.From downstream to upstream of Shiting River,the hazards get more serious,and the geo-hazards are well developed along the front range fracture and middle range fracture,the latter is more serious than the former.Seismic geological hazard development are controlled by the seismic fracture,topography,rock mass structure and human activities,the coupling of those controlling factors is the main reason for the inhomogeneous distribution of the seismic geo-hazards in Shiting River region.