瞬变电磁法二维逆时偏移

TWO-DIMENSIONAL COUNTER-TIME SHIFT IN TRANSIENT ELECTROMAGNTIC METHOD

本文简要介绍了电磁偏移的基本原理和低频滤波的偏移处理方法 ,并详细论述了最佳极值时刻T的求取方法。电磁偏移以斯特莱顿 -朱型积分为理论基础 ,借助于无限均匀介质中的格林函数 ,描述了似稳电磁场在下半空间的传播过程。利用电磁偏移方法处理TEM资料 ,能够较准确地确定局部导电地质体的空间位置 ,处理速度快 。

The present paper briefly describes the basic principle of electromagnetic shift and shift processing method of low frequency filtering,and deals in detail with the technique for figuring out optimum extremum time T .With Straton Chu intergral as the theoretical basis and by means of Green's function in infinite uniform media,the electromagnetic shift describes the propagation process of quasi stationary electromagnetic field in lower half space.Using the electromagnetic shift method to TEM data processing,one can rather accurately locate local conductive geological bodies,benefit from high processing speed and obtain vivid interpretation result.