三维精细积分法地震正演及边界条件

3-D fine integration seismic forward modeling and boundary condition

将任意差分精细积分法用于三维波动方程地震正演,关键在于如何消除数值计算中有限波场区域边界引起的边界反射。文中采用Berenger给出的电磁波完全匹配层吸收边界条件,推导出三维波动方程任意差分精细积分法地震正演的完全匹配层吸收边界条件计算公式,并给出了完全匹配层吸收边界条件算例。计算结果表明,此方法压制边界反射效果明显。三维波动方程地震正演模拟实例表明,完全匹配层吸收边界条件的任意差分精细积分法为复杂区地震波传播规律研究提供了一种实用的正演模拟工具。

The paper uses the arbitrary difference fine integration for 3-D wave equation seismic forward modeling, the key issue of which is how to eliminate the boundary reflection from the boundary of finite wavefield region in numeric computation.The paper adopts the absorption boundary condition of electromagnetic wave fully-matched layer presented by Mr.Berenger,deduces computation formula of 3-D wave equation arbitrary difference fine integration seismic forward modeling with absorption boundary condition of fully-matched layer and gives computational cases of absorption boundary condition of fully-matched layer.The computational results showed that the approach has identified effects of suppressing the boundary reflection.The 3-D wave equation seismic forward modeling cases showed that the arbitrary difference fine integration with absorption boundary condition of fully-matched layer provides a practical forward modeling tool for study of seismic wave propagation in complex area.