弹性介质中垂直地震剖面有限差分正演

Finite difference modelling for vertical seismic profile in elastic media

垂直地震剖面法可以通过认识反射和透射过程,深入了解地震波传播特性,又可以改善地表地震资料关于构造、地层和岩性的解释.本文是在基于垂直地震剖面的基本原理基础上,采用高阶交错网格有限差分数值求解二维弹性波方程,然后对常见的层状介质和岩溶介质模型分别进行模拟,根据模型合成了相关的垂直地震剖面记录,期间采用的是完全匹配层法吸收边界条件,从记录中可以看见该边界条件的简单而高效的优点,最后对模型的复杂程度的不足提出了进一步的要求以适应更复杂的地质条件.

Vertical seismic profiling can be used to get the reflections and refractions, deeply know the seismic propagation characteristics, and then explain the seismic data about structures, layers, lithological character. Based on the theory of vertical seismic profile, this paper takes high order staggered-grid finite difference method to resolve the wave equation for the synthetic VSP in the layered media and the karst media. Meanwhile, it takes the perfectly matched layers method as the absorbing boundary condition, so it will deal with the boundary condition simply and efficiently. Finally it is more important that we get more complex models with more complex geological conditions.