地质论评2025，Vol.71Issue(5)：1534-1544,11.DOI:10.16509/j.georeview.2025.01.011
基于水平共面一发双收磁偶极装置的瞬变电磁早期二次场信号提取研究
Research on transient electromagnetic early secondary field signal extraction based on horizontal coplanar one-transmitting and dual-receiving magnetic dipole device
摘要
Abstract
Objectives:In the process of transient electromagnetic detection,the receiving coil will be disturbed by the primary field,which makes it difficult to accurately extract the secondary field caused by the geological body in the early total field signal.Therefore,the late signal is often used to carry out exploration work.The author intends to design a device and calculation method for extracting early secondary field signals to be applied to shallow exploration. Methods:Based on the conductive ring model,the influence of the primary field on the secondary field signal under different delay conditions was analyzed.According to the magnetic induction distribution characteristics of the transmitting coil in space,the numerical conditions for the cancellation of the primary field are derived. Results:The simulation results show that under the influence of the primary field,the earlier the time is,the greater the difference between the total field and the secondary field response is.Through theoretical calculation,the conversion coefficient of the reference coil relative to the primary field in the receiving coil is obtained,and then the primary field in the receiving coil is offset by the digital compensation method.Automobile experiments show that the pressing rate of the primary field can reach more than 90％. Conclusions:Compared with the traditional magnetic dipole device,the application of the one-transmitting and dual-receiving device and the secondary field extraction method proposed in this paper can effectively cancel the primary field signal in the total field response,so that the early secondary field signal containing abnormal information can be utilized.It is verified by underground pipeline detection test that the method has a good detection effect in practical work,which is of great significance to improve the ability of shallow geological body anomaly recognition.关键词
瞬变电磁法/水平共面磁偶极装置/数字信号补偿/一次场压制Key words
transient electromagnetic method/horizontal coplanar magnetic dipole device/digital signal compensation/a field suppression引用本文复制引用
王家明,李海侠,刘慧鹏..基于水平共面一发双收磁偶极装置的瞬变电磁早期二次场信号提取研究[J].地质论评,2025,71(5):1534-1544,11.基金项目
本文为国家自然科学基金资助项目(编号:42064005)的成果. This study was supported by the Natural Science Foundation of China(No.42064005) （编号:42064005）
