磁性条件下频率域航空电磁正演计算和成像研究  

Study of frequency airborne electromagnetic forward calculation and imaging under magnetic condition

作　　者：习建军[1,2] 崔丹丹[1] 张文双[1] 陈雄[2] 

机构地区：[1]河北省电力勘测设计研究院,石家庄050031 [2]吉林大学地球探测科学与技术学院,长春130026

出　　处：《地球物理学进展》2016年第6期2700-2706,共7页Progress in Geophysics

基　　金：2013年博士点基金项目(20130061110060博导类);国家高技术研究发展计划(863)项目子课题(2012AA052801);国家重点基础研究发展计划973项目(2013CB429805)联合资助

摘　　要：频率域航空电磁响应计算中,如何计算积分方程是频率域航空电磁法正演计算的难点,本文把电磁响应计算公式分解成汉克尔变换式和普通积分或者超几何函数的两项之和,然后分析核函数中反射系数的衰减规律,通过对比线性滤波算法和直接数值积分法的积分效果,选择了120点线性滤波算法计算汉克尔变换,采用高密度方法在确保计算精度的条件下显著提高了频率域航空电磁响应计算效率.针对强磁性区域频率域航空电磁法反演问题,在传统相位矢量图只包含电阻率和飞行高度两个参数的基础上,添加了磁导率的计算,绘制了包含磁导率、电阻率、飞机飞行高度三个参数的三维相位矢量图,计算结果表明,三维相位矢量图插值可以用于简单的一维模型,反演速度快、效率高,有助于提高磁性区域地下目标体的探测准确率,对于强磁性区域航空电磁法视电阻率填图是一种行之有效的勘探方法.In the calculation of the electromagnetic response of the frequency domain,how to calculate the integral equation is the difficulty of forward calculation. In this paper,the electromagnetic response formula is decomposed into the sum of two items of Hankel transform and ordinary integral or hypergeometric function,and the attenuation law of reflection coefficient in the kernel function is analyzed. By comparing the integral effect of the linear filtering algorithm and the direct numerical integration method,We select 120 point linear filtering algorithm for computing Hankel transform,use the high density method to significantly improve the efficiency of the electromagnetic response of the frequency domain under the condition of ensuring the accuracy of calculation. Aiming at the inverse problem of electromagnetic method in the frequency domain of strong magnetic domain,We add the calculation of permeability based on the two parameters of resistivity and flight height in the traditional phase vector diagram, and draw a three-dimensional phase vector diagram with three parameters,including permeability,resistivity,aircraft flying height. The calculation results show that the three-dimensional phase vector interpolation method can be used to calculate the simple one-dimensional model. It has high speed and high efficiency, and it is helpful to improve the detection accuracy of the magnetic field underground target. So,it is an effective exploration method for the apparent resistivity mapping in strong magnetic area.

关 键 词：频率域航空电磁法 汉克尔变换 三维相位矢量图 视电阻率填图 

分 类 号：P631[天文地球—地质矿产勘探]