基于蒙特卡洛方法的瞬变电磁接收机过渡过程研究  

Research on Transient Electromagnetic Receiver Transient Process Based on Monte Carlo Method

作　　者：王广君[1,2] 段雪影 黄鲸珲 胡祥云[3,4] Wang Guangjun;Duan Xueying;Huang Jinghui;Hu Xiangyun(School of Automation,China University of Geosciences,Wuhan Hubei 430074,China;Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems,China University of Geosciences,Wuhan Hubei 430074,China;Institute of Geophysics and Geomatics,China University of Geosciences,Wuhan Hubei 430074,China;State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan Hubei 430074,China)

机构地区：[1]中国地质大学自动化学院,湖北武汉430074 [2]中国地质大学复杂系统先进控制与智能自动化湖北省重点实验室,湖北武汉430074 [3]中国地质大学地球物理与空间信息学院,湖北武汉430074 [4]中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉430074

出　　处：《工程地球物理学报》2022年第5期585-594,共10页Chinese Journal of Engineering Geophysics

基　　金：国家自然科学基金(编号:42220104002,41630317);地质过程与矿产资源国家重点实验室科技部专项(编号:MSFGPMR01-4);中央高校基本科研业务费专项(编号:G1323519204);中国国家留学基金(编号:202206410063)。

摘　　要：传统的瞬变电磁法在浅层存在探测盲区,限制了在浅层地表结构探测中的应用。瞬变电磁探测仪接收机的过渡过程的影响是导致浅层存在探测盲区的主要原因之一。当发射机关断时间及发射电流确定的情况下,接收机电路的过渡过程会导致实测信号发生畸变,影响浅层数据的反演。本文通过对接收机接收线圈的二阶电路建模分析,结合自制的瞬变电磁系统“WLZTEM-2022”的实测数据,在已知均匀半空间条件下通过蒙特卡洛反演得到接收线圈的rLC参数,从而实现对瞬变电磁法浅层探测信号的矫正。实验结果表明,通过过渡过程校正后的早期瞬变电磁探测数据更接近瞬变电磁的早期正演数据,通过计算本文定义的误差函数,校正后的误差定量上比矫正前的误差约减小了3倍;此外,通过把反演得到的过渡过程中rLC参数加入到传统的瞬变电磁正演算法中,可以得到对过渡过程准确建模后的早期(t<1μs)的理论总场曲线,从而提高瞬变电磁系统浅层(0~5 m)的探测能力。本文研究成果对提高瞬变电磁法浅层探测精度、减小早期探测盲区具有实际应用价值。The traditional transient electromagnetic method(TEM)has a blind spot in shallow detection,which limits its application in shallow surface structure detection.The influence of the transition process of the TEM receiver is one of the main reasons for the detection blind area in shallow layer.When the turn-off time and transmission current of the transmitter are determined,the transition process of the receiver circuit will lead to the distortion of the measured signal and affect the precision of the inversion of shallow detection.In this paper,through modeling and analysis of the second-order circuit of the receiver,combined with the measured data of the self-made transient electromagnetic system“WLZTEM-2022”,rLC parameters of the receiving coil are obtained through inversion under the condition of known uniform half-space.Thus the shallow detection signal of TEM can be corrected.The experimental results show that the early transient electromagnetic detection data corrected by the transition process is very close to the early forward transient electromagnetic data.According to the error function defined in this paper,the error after correction is about 3 times smaller than that before correction.In addition,by adding the rLC parameters in the transition process obtained by inversion into the traditional TEM forward algorithm,the numerical simulation results verify that the accurate modeling of the transition process can obtain the theoretical total field curve at the early stage(t<1μs),and improve the detection ability of the shallow layer(0~5 m)of the transient electromagnetic system.The research results of this paper have practical application value for improving the shallow detection accuracy and reducing the early detection blind area.

关 键 词：瞬变电磁法 浅层探测 SIMULINK 过渡过程 

分 类 号：P631.3[天文地球—地质矿产勘探]