高阶时域有限差分法的多偏移距电磁波数值成像  

High-order FDTD method for multi-offset electromagnetic numerical imaging

作　　者：汪科[1,2] WANG Ke(College of Electrical and Information Engineering, Guangxi University of Science and Technology, Liuzhou 545006, China Hunan Railway Profes-sional Technology College, Zhuzhou 412001 , China)

机构地区：[1]广西科技大学电气与信息工程学院,广西柳州545006 [2]湖南铁道职业技术学院,湖南株洲412001

出　　处：《物探与化探》2017年第3期489-495,共7页Geophysical and Geochemical Exploration

基　　金：湖南省教育厅科学研究项目(15B156)

摘　　要：数值模拟是数据处理和反演解释的重要环节,为提高高频电磁波层析成像技术在工程勘察中的解译准确性,采用高阶时间域有限差分法(FDTD(2,4))模拟电磁波在溶洞、断层和孤石等3种地电模型下的成像过程,并采用多偏移距模式获取电磁波道集。通过分析电磁波的波场快照结果和成像结果,总结了电磁波在不同地质体中的传播规律,为实际工程勘察工作提供可靠依据。试验结果表明,FDTD(2,4)能高精度模拟电磁波在复杂介质中的数值成像,同时也验证了多偏移距采集模式具有高效性和灵活性。Numerical simulation is an important part of data processing and inversion interpretation. In order to improve the efficiency and the accuracy of electromagnetic wave imaging technolog^^ in engineering sur^^ey, it is important to understand the propagation char-acteristics of electromagnetic waves by for^-ard modeling. In this study, the finite-difference time-domain FDTD （2, 4） was used to simulate the numerical imaging of electromagnetic waves in three kinds of geoelectric models, i.e., karst caves, faults and boulders. The multi-offset mode was used to acquire the electromagnetic wave gathers. Based on the analysis of the electromagnetic wave wavefield and the waveform profile, the authors summarized the propagation law of electromagnetic waves in different geological bodies and pro-vided reliable basis for practical engineering investigation. The experimental results show that FDTD （2,4） can simulate the numerical imaging of electromagnetic waves in complex media with high accuracy, and also prove that the multi-offset acquisition mode has high efficiency and flexibility.

关 键 词：高阶时域有限差分 多偏移距 电磁波层析 数值成像 工程勘察 

分 类 号：P631[天文地球—地质矿产勘探]