TEM正演响应计算的几种频-时域转换方法对比  

Comparison of several frequency-time transformation methods for TEM forward modeling

作　　者：李锋平[1] 杨海燕[1] 邓居智[1] 汤洪志[1] 刘旭华[1] 赵海娇[1] 

机构地区：[1]东华理工大学放射性地质与勘探技术国防重点学科实验室,江西南昌330013

出　　处：《物探与化探》2016年第4期743-749,共7页Geophysical and Geochemical Exploration

基　　金：江西省自然科学基金项目(20151BAB203045);江西省教育厅科学技术研究项目(GJJ14487);放射性地质与勘探技术国防重点学科实验室开放基金(RGET1308);国家自然科学基金项目(41564001;41164003;41264004;41174107)联合资助

摘　　要：在瞬变电磁的一维正演响应模拟中,常用的方法是先在频率域中求解,之后将结果转换到时间域。但该方法在晚期的计算精度通常不高,因此,使用5种频-时域转换方法(正、余弦变换的数值滤波算法,G-S逆拉普拉斯算法、正、余弦变换的折线逼近法)进行了计算,与解析解对比,得出余弦变换的数值滤波算法在晚期计算中精度最高的结论,并对这五种转换方法产生误差问题的原因进行了讨论和分析。本研究有利于瞬变电磁一维正演响应的高精度计算,使其在多维计算中得到更好的应用。In the forward modeling of transient electromagnetic response,the commonly used method is to calculate the response in the frequency domain,and then the results were converted into the time domain. In this paper,five frequency-time conversion methods（ Digital filtering algorithms of sine and cosine transform,G-S inverse Laplace algorithm,polygonal approximations method of sine and cosine transform） were used to conduct calculation. it is concluded that the digital filtering method based on cosine transform has the highest computing precision among these five methods,as shown by the comparison with the analytical algorithm,and the reasons of the error caused by these five kinds of conversion methods were discussed and analyzed,which is beneficial to the high precision calculation of one- dimensional forward modeling of transient electromagnetic response,so that these methods can be better applied to the calculation of multi-dimensional frequency-time conversion.

关 键 词：瞬变电磁 频-时域转换 数值滤波 G-S逆拉普拉斯算法 折线逼近 

分 类 号：P631[天文地球—地质矿产勘探]