大定源回线瞬变电磁场数值滤波算法  

A digital filter method for evaluating the fixed-loop transient electromagnetic field

作　　者：刘云[1] 宋滔[1] 王赟[1] 

机构地区：[1]中国科学院地球化学研究所矿床地球化学国家重点实验室,贵阳550081

出　　处：《物探化探计算技术》2016年第4期437-442,共6页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家"973计划"项目(2014CB440905);国家自然科学基金(41440031);贵州省科学技术基金(2014GZ93278)

摘　　要：在前人的工作基础上,给出一种新的快速计算框线源激发的瞬变电磁场的数值滤波算法,其中内层积分的Hankel积分式采用47点J1型线性滤波系数,外层积分采用"n点式"Gauss-Legendre数值积分法。通过线性迭加技术,将多个单线源组合成任意多边形的瞬变电磁的发射框源。算例分析表明,数值计算结果和解析解的最大相对误差小于0.007%,单测点、单时间道的计算耗时为0.1s。该方法可应用于瞬变电磁法生产实际中确定出最小延迟时间,以避免"框线效应"对瞬变电磁场的畸变影响。Based on the studies of Nabighian（1984）and DING Yan-fei（2012）,a new digital filtering algorithm is presented to evaluate the transient electromagnetic（TEM）field induced by a line source.Among them,the inner integral Hankel integral formula using 47-point J1 type linear filtering coefficients,outer integral formula using＇n-point＇Gauss-Legendre numerical integration method.Through linear superposition of a plurality of single line source emission source combined into arbitrary polygon transient electromagnetic.Example analysis shows that the maximum relative error of the numerical results and the analytical solution is less than 0.007%,and the computation time of single point and single time channel is 0.1s.The method can be applied to the production of transient electromagnetic method to determine the minimum delay time,so as to avoid the influence of border effects on the transient electromagnetic field.

关 键 词：大定源回线 瞬变电磁场 数值滤波算法 框线效应 

分 类 号：P631.3[天文地球—地质矿产勘探]