FCTEM小回线瞬变电磁法与微动在地下岩溶高效精准探测中的应用研究  

The Application of FCTEM Small-return Transient Electromagnetic Method and Micro-motion in Efficient and Accurate Detection of Underground Karst

作　　者：王小勇[1] 张志 许强平 胡俊杰[1] Wang Xiaoyong;Zhang Zhi;Xu Qiangping;Hu Junjie(Anhui Engineering Survey Institute Co.,Hefei Anhui 230011,China)

机构地区：[1]安徽工程勘察院有限公司,安徽合肥230011

出　　处：《工程地球物理学报》2025年第2期199-206,共8页Chinese Journal of Engineering Geophysics

基　　金：中央财政资金(编号:2021ANNFN00738)。

摘　　要：为降低安全风险,在岩溶发育区开展工程建筑活动需要详细查明地下溶洞分布情况。以往岩溶探测主要通过钻探结合传统电法勘探来实施,但密集式钻探往往成本高、耗时长,传统电法勘探精度较低,构建基于经济性和精确性的岩溶探测技术模式成为迫切需要解决的问题。基于此,以安徽省庐江县某岩溶发育区为靶区,结合区内钻孔验证情况,开展了FCTEM(Fast Cut-off Transient Electromagnetic)小回线瞬变电磁法与微动在地下岩溶探测中的应用研究,结果表明:①FCTEM小回线瞬变电磁法横向分辨率高,初步反演深度存在误差;微动纵向分辨率高,反演深度相对可靠;②基于钻孔揭露和微动成果的约束反演提高了FCTEM纵向分辨率,有效查明了区内岩溶剖面、平面和空间分布特征;③综合FCTEM瞬变电磁法扫面、微动验证及钻探约束的探测模式,可以实现连通性充填型岩溶高效、精准的探测。本文探测方案为相近地区提供了技术参考,具备一定的推广价值。In order to reduce safety risks,it is necessary to find out the distribution of underground Karst caves in detail in order to carry out engineering construction activities in Karst development areas.In the past,Karst exploration was mainly carried out by drilling combined with traditional electrical prospecting.However,intensive drilling is often costly and time-consuming,and the accuracy of traditional electrical prospecting methods is low.Therefore,it is an urgent issue to construct a Karst detection technology model based on economy and accuracy.Based on this,taking a Karst development area in Lujiang County,Anhui Province as the target area,combined with the drilling verification in the area,the application of FCTEM(fast cut-off transient electromagnetic)small loop transient electromagnetic method and microtremor in underground Karst detection was conductedt.The results show that:①The lateral resolution of FCTEM small loop transient electromagnetic method is high,and there are errors in the initial inversion depth;the longitudinal resolution of micro-motion is high,and the inversion depth is relatively reliable.②The constrained inversion based on borehole exposure and micro-motion results improves the vertical resolution of FCTEM,effectively identifying thet profile,plane and spatial distribution characteristics of the Karst in the area.③By combining the detection mode of FCTEM transient electromagnetic method scanning,micro-motion verification and drilling constraints,the efficient and accurate detection of connected filling Karst can be realized.This detection scheme can provide valuable technical reference for similar areas and has certain value for further application.

关 键 词：瞬变电磁法 微动 岩溶探测 高效精准 应用研究 庐江县 

分 类 号：P631[天文地球—地质矿产勘探]