Landslide monitoring in southwestern China via time-lapse electrical resistivity tomography  

西南山区典型滑坡体时移电阻率动态监测试验研究（英文）

作　　者：徐冬[1] 胡祥云[1] 单春玲[1] 李睿恒[1] 

机构地区：[1]中国地质大学(武汉)地球物理与空间信息学院,地球内部多尺度成像湖北省重点实验室,武汉430074

出　　处：《Applied Geophysics》2016年第1期1-12,217,共13页应用地球物理（英文版）

基　　金：funded by the National Basic Research Program of China(973 Program)(No.2013CB733203);the National Natural Science Foundation of China(No.41474055)

摘　　要：The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability,rainwater infiltration,and subsurface hydrogeology.However,the understanding of this complicated correlation is still poor and inadequate.Thus,in this study,we investigated a typical landslide in southwestern China via time-lapse electrical resistivity tomography（TLERT） in November 2013 and August 2014.We studied landslide mechanisms based on the spatiotemporal characteristics of surface water infiltration and flow within the landslide body.Combined with borehole data,inverted resistivity models accurately defined the interface between Quaternary sediments and bedrock.Preferential flow pathways attributed to fracture zones and fissures were also delineated.In addition,we found that surface water permeates through these pathways into the slipping mass and drains away as fissure water in the fractured bedrock,probably causing the weakly weathered layer to gradually soften and erode,eventually leading to a landslide.Clearly,TLERT dynamic monitoring can provide precursory information of critical sliding and can be used in landslide stability analysis and prediction.滑坡体动态监测研究聚焦于降水入渗、坡体内部水文地质条件和坡体稳定性之间的复杂耦合关系。我们选择西南山区典型滑坡体,于2013年11月和2014年8月开展时移电阻率层析成像监测工作,以滑坡体电性结构的时间一空间特性来表征地表水入渗及地下水迁移的时空分布规律,构建滑坡演化及其触发的动态过程。结合地质钻孔资料,电阻率反演模型准确划定了基岩与上覆第四系沉积物间的分界面;同时圈定了发育为潜在优先流路径的破碎带网络,推断地表水沿此路径入渗并经基岩风化裂隙水径流排泄,基覆面溶蚀软化致使滑动面逐渐贯穿。研究结果表明时移电阻率监测具备获取临滑前兆信息的潜力,能够为滑坡稳定性分析和预测预报提供准确可靠的依据。

关 键 词：time-lapse electrical resistivity tomography LANDSLIDE HYDROGEOPHYSICS MONITORING preferential flow 

分 类 号：P642.22[天文地球—工程地质学] P631.322[天文地球—地质矿产勘探]