Electrical Characteristics of Tangjiawan Landslide in Lixian, Sichuan

中国四川理县唐家湾滑坡电性特征

A wide range of terrain features and landforms,which are exemplified by intricate geological formations and diverse rock compositions,are found in the western mountainous regions of China.These areas frequently encounter geological disasters.As one of the natural disasters,landslides lead to considerable loss of human life and property.Considering mitigation of the losses caused by landslide disasters,a necessary measure for disaster prevention and mitigation involves conducting detailed investigations and monitoring of landslides,which is also the cornerstone of landslide warning.This study compares and analyzes the feasibility of the magnetotelluric detection method for landslides using the results of engineering geological surveys and landslide monitoring.The study aims to address the scientific problem of the validity of using magnetotelluric methods to detect landslide development processes.The Tangjiawan landslide signal on the left side of the K94+000~K94+145 section of the Wenma Expressway is analyzed by employing engineering geological survey,magnetotelluric detection,landslide monitoring,landslide analysis,and other methods.Analysis results provide the static electrical characteristics of lithology,structure,and groundwater,as well as the dynamic electrical characteristics of landslide development.This study focuses on analyzing the relationship between the methods of magnetotelluric detection and engineering geological surveys and the results of landslide monitoring.The workflow and methods for data collection,processing,inversion,interpretation,and analysis using the magnetotelluric method to detect the dynamic development process of landslides are presented in the conclusion.Preliminary conclusions indicate a strong correlation between the dynamic changes in magnetotelluric wave impedance with the surface displacement of landslides and the dynamic changes in groundwater.The use of the magnetotelluric method for landslide detection and monitoring is a feasible example.The research results can offer certain technical references for the detection and monitoring of landslides using magnetotelluric methods and also provide references and guidance for the selection of diversified landslide monitoring methods in the future.

中国西部山区地形地貌多样,地层岩性及地质构造复杂,地质灾害频发,滑坡是使人类受到重大生命财产损失的自然灾害之一。为减少滑坡灾害造成的损失,对滑坡体开展详细勘察及监测成为防灾减灾必要的手段,也是滑坡预警的基石。本研究,采用工程地质勘察成果及滑坡监测成果对比分析验证大地电磁探测滑坡方法可行的技术路线,拟解决应用大地电磁法探测滑坡发育过程方法有效性的科学问题。采用工程地质勘察、大地电磁法探测、滑坡监测、滑坡分析等多种方法,展开汶马高速K94+000~K94+145段左侧唐家湾滑坡的研究。结果给出了地层岩性、结构、地下水的静态电性特征,滑坡发育的动态电性特征,重点分析了大地电磁法探测与工程地质地质勘察及滑坡监测成果之间的相关关系。结论给出了采用大地电磁法探测滑坡动态发育过程的数据采集、处理、反演、解释、分析的流程及方法,初步得出电磁波波阻抗动态变化与滑坡地表位移、地下水动态变化具有较强的相关性,给出了采用大地电磁法探测和监测滑坡方法的可行性实例。研究成果可为滑坡大地电磁法探测和监测提供一定的技术参考,可为未来多元化滑坡监测方法选择提供一定的借鉴和参考。