不导水断层构造的二维瞬变电磁响应特征研究  

Study on response characteristics of 2D transient electromagnetic of non-water-conducting fault structure

作　　者：乔元栋 杨振强 焦俊俊 牛兴国 兰永青 谭丁瑞 QIAO Yuandong;YANG Zhenqiang;JIAO Junjun;NIU Xingguo;LAN Yongqing;TAN Dingrui(College of Architectural and Surveying Engineering,Shanxi Datong University,Datong 037003,China;College of Energy and Transportation Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;College of Geoscience and Surveying Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;Nonferrous Geological Bureau of Inner Mongolia Autonomous Region,Hohhot 010010,China;Shandong Zhengyuan Geophysical Information Technology Co.,Ltd.,Jinan 250101,China)

机构地区：[1]山西大同大学建筑与测绘工程学院,山西大同037003 [2]内蒙古农业大学能源与交通工程学院,内蒙古呼和浩特010018 [3]中国矿业大学(北京)地球科学与测绘工程学院,北京100083 [4]内蒙古自治区有色地质勘查局,内蒙古呼和浩特010010 [5]山东正元地球物理信息技术有限公司,山东济南250101

出　　处：《中国矿业》2024年第1期122-129,共8页China Mining Magazine

基　　金：山西省基础研究计划(自由探索类)基金项目资助(编号:20210302124355)。

摘　　要：采煤面前方隐伏不导水断层是煤矿开采现场的潜在事故隐患,需要对其展开细致研究。首先,引入了二维瞬变电磁正演计算公式,并采用有限单元数值计算方法进行了求解,数值计算结果与解析解的结果较吻合。其次,建立含断层构造和不含断层构造的二维地质模型,并对模型进行数值计算。研究结果表明:感应磁场等值线对高阻断层构造的响应规律明显,等值线畸变的形状和范围与模型中断层的位置、走向和倾角吻合度较好。随着测点位置与断层的距离减小,感应电动势响应幅值在采样早期呈增大趋势,但尖点响应的最小幅值逐渐变大,有断层模型的尖点响应下凹的幅度相较无断层模型更大。视电阻率成像结果能较好地反映高阻断层与煤系地层的电性特征,表明正演结果准确可靠。The hidden non-water-conducting fault in front of the coal mining face is a potential accident potential danger in the coal mining site,so it needs to be studied in detail.Firstly,the forward calculation formula of 2D transient electromagnetic is introduced and solved by finite element numerical calculation method.The numerical results are in good agreement with the analytical results.Secondly,a 2D geological model with fault structure and without fault structure is established,and the model is numerically calculated.The research shows that the response law of the induced magnetic field contour to high resistivity fault structure is obvious,and the shape and scope of the contour distortion are in good agreement with the position,direction and dip angle of the fault in the model.With the decrease of the distance between the location of measuring point and the fault,the amplitude of the induced electromotive force response shows an increasing trend in the early sampling period,but the minimum amplitude of the tip response gradually increases,and the amplitude of the tip response concave with the fault model is larger than that without the fault model.The apparent resistivity imaging results can better reflect the electrical characteristics of the high blocking layer and the coal-bearing strata,indicating that the forward modeling results are accurate and reliable.

关 键 词：瞬变电磁法 断层 有限单元法 数值模拟 正演 

分 类 号：TD74[矿业工程—矿井通风与安全] P631.325[天文地球—地质矿产勘探]