线圈中心测量垂直磁场虚分量频域电磁法数值模拟
来源期刊：中南大学学报(自然科学版)2013年第4期
论文作者：谢维 王京彬 朱谷昌 杨生
文章页码：1444 - 1452
关键词：垂直磁场虚分量；数值模拟；频域电磁法
Key words：magnetic field vertical imaginary component; numerical simulation; frequency domain electromagnetic sounding
摘 要：提出一种在近区测量磁场垂直虚分量提取视电阻率的频率域电磁测深方法，通过分析其特性并进行数值模拟研究，建立近区频率域电磁测深理论体系。通过研究线圈中心均匀大地电磁场，推导相关解析表达式，并将成熟的双频和伪随机合成电流移植到本方法中。根据一定近似条件下电磁场的理论公式，研究载流线圈中心垂直磁场虚分量提取视电阻率的方法特性，并编写相应正演程序，对2层、3层、4层等地电模型进行数值模拟，分析结果显示其对地下电性分布变化的有较高分辨力。最后根据模拟结果揭示本方法可行性及实际意义。
Abstract: A new frequency domain electromagnetic sounding method of extracting apparent resistivity was put forward through measuring its near of zone magnetic field vertical virtual component, and a theoretical system of near zone frequency domain electromagnetic sounding method was constructed by analyzing its characteristics and conducting numerical simulation, and a theoretical foundation was provided for the design of the observing system. The method integrates the mature formula of dual and pseudo-random synthetic current by studying the coil center homogeneous magnetotelluric field and deducing the related analytical expression. According to the theoretical formula of magnetic field under certain approximate conditions, the method characteristics on extracting apparent resistivity were studied by vertical virtual component of magnetic field at current-carrying coil center, the corresponding forward programs were written and its better resolution on underground electrical distribution changes through numerical simulation on two-layered, three-layered, four-layered geoelectric models. The feasibility and significance of the method are revealed based on the simulation results.
谢维1, 2，王京彬2，朱谷昌2，杨生2
(1. 中南大学 地球科学与信息物理学院，湖南 长沙，410083；2. 北京矿产地质研究院，北京，100012)
摘 要：提出一种在近区测量磁场垂直虚分量提取视电阻率的频率域电磁测深方法，通过分析其特性并进行数值模拟研究，建立近区频率域电磁测深理论体系。通过研究线圈中心均匀大地电磁场，推导相关解析表达式，并将成熟的双频和伪随机合成电流移植到本方法中。根据一定近似条件下电磁场的理论公式，研究载流线圈中心垂直磁场虚分量提取视电阻率的方法特性，并编写相应正演程序，对2层、3层、4层等地电模型进行数值模拟，分析结果显示其对地下电性分布变化的有较高分辨力。最后根据模拟结果揭示本方法可行性及实际意义。
关键词：垂直磁场虚分量；数值模拟；频域电磁法
XIE Wei1, 2, WANG Jingbin2, ZHU Guchang2, YANG Sheng2
(1. School of Geoscience and Info-Physics, Central South University, Changsha 410083, China;2. Beijing Institute of Geology for Mineral Resources, Beijing 100012, China)
Abstract:A new frequency domain electromagnetic sounding method of extracting apparent resistivity was put forward through measuring its near of zone magnetic field vertical virtual component, and a theoretical system of near zone frequency domain electromagnetic sounding method was constructed by analyzing its characteristics and conducting numerical simulation, and a theoretical foundation was provided for the design of the observing system. The method integrates the mature formula of dual and pseudo-random synthetic current by studying the coil center homogeneous magnetotelluric field and deducing the related analytical expression. According to the theoretical formula of magnetic field under certain approximate conditions, the method characteristics on extracting apparent resistivity were studied by vertical virtual component of magnetic field at current-carrying coil center, the corresponding forward programs were written and its better resolution on underground electrical distribution changes through numerical simulation on two-layered, three-layered, four-layered geoelectric models. The feasibility and significance of the method are revealed based on the simulation results.
Key words:magnetic field vertical imaginary component; numerical simulation; frequency domain electromagnetic sounding
