中文摘要：

介绍一种基于三维时域有限差分法（FDTD）的有耗色散地质介质中电磁波传播特性数值分析方法。通过将色散介质本构关系和场量关系直接变换为时域微分方程的方法，导出了适用于一般色散介质中电磁场分析的时域有限差分法计算公式，并将完全匹配层（PML）吸收边界融入了FDTD计算格式。通过计算分析了介质色散对电磁波场传播的影响，观测到介质色散会导致电磁脉冲在传播中波形展宽、位相滞后、幅度减小。因此，电磁探测数据的处理解释应将介质的色散影响纳入考虑。

英文摘要：

This paper presents a three dimensional finite-difference time-domain （FDTD） modeling technique for the electromagnetic field in lossy dispersive earth media. The FDTD schemes are deduced by transforming directly the constitutive relations of dispersive media and the relations of the electromagnetic field components into time-domain differential equations. The perfectly matched layer （PML） is extended to match the dispersive media and used as an absorbing boundary condition to simulate the open space. The paper describes the numerical simulation of the electromagnetic wave propagation in lossy dispersive earth media. The modeling results show that the dispersion of the media has a notable effect on the electromagnetic wave propagation and will make the pulse waveform broaden and the phase delay. The dispersion of the media should be taken into account during the data processing and the interpretation of electromagnetic methods.