半航空瞬变电磁法在西南山区隧道勘察应用研究  

Research on the application of the semi-aeronautical transient electromagnetic method in tunnel investigation in southwest mountainous areas

作　　者：张东清 张赛民[1] 王献 杨正东 ZHANG Dongqing;ZHANG Saimin;WANG Xian;YANG Zhengdong(College of Geophysics,Chengdu University of Technology,Chengdu 610059)

机构地区：[1]成都理工大学地球物理学院,成都610059

出　　处：《物探化探计算技术》2025年第2期272-281,共10页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：电磁勘察(2020开放基金)(40100-02020410)。

摘　　要：在隧道物探资料采集中,由于地形陡峻,导致常规地面物探设备及人员难以到达隧道中线位置,出现了大段物探资料缺失的问题。针对隧道物探资料采集中因地形陡峻导致的数据缺失问题,笔者试图探讨半航空瞬变电磁法在隧道勘察的适用性。通过正演算法,模拟了感应电动势三分量的平面特征变化,发现在单侧测量时,电磁场的z分量不出现场值反转现象,探讨了K、H型模型中间层厚度以及电阻率变化对电磁响应值的影响,结果显示,在相同地电参数下,z分量响应值显著高于x、y分量,在晚期,y分量的相对异常小于x和z分量。最后对依照一条公路隧道勘察一条隧道的电阻率剖面图和钻探结果进行分析,结果对应良好,证明了半航空瞬变电磁法在隧道勘查中可作为一种有效手段。In collecting geophysical data for tunnels,due to the steep terrain,conventional ground geophysical equipment and personnel are often unable to reach the central line of the tunnel,resulting in large sections of missing geophysical data.In view of the data loss problem due to steep terrain in the collection of tunnel geophysical data,this paper explores the applicability of the semiairborne transient electromagnetic method in tunnel surveys.The planar characteristics of the three components of induced electromotive force are simulated through forward modeling algorithms.It is found that when measuring on one side only,the zcomponent of the electromagnetic field does not exhibit field value inversion.The impact of variations in the thickness and resistivity of the intermediate layer on electromagnetic response values within the K and H models was examined.The results show that,under the same geoelectric parameters,the response value of the z-component is significantly higher than those of the x and y components,and in the later stage,the relative anomaly of the y-component is smaller than those of the x and z components.Ultimately,the resistivity profile obtained from a survey conducted along a highway tunnel was analyzed in conjunction with the drilling results,demonstrating a high degree of correlation.This evidence confirms that the semi-airborne transient electromagnetic method can effectively perform tunnel surveys.

关 键 词：半航空瞬变电磁法 三分量 隧道勘察 正演模拟 

分 类 号：P631[天文地球—地质矿产勘探]