混合域三维VSP波动方程深度偏移方法

3-D VSP wave equation depth migration in mix domain

常规VSP成像方法利用VSP-CDP转换或基尔霍夫偏移,存在保幅性差及成像精度低等问题。混合域三维VSP波动方程深度成像方法是将VSP反射P波在深度域直接成像,利用分步傅里叶法在混合域进行波场外推,即在频率—波数域实现波场的相移,在频率—空间域实现时移校正。此法的优点在于能保持横向变速地质构造波动方程波场外推精度的同时提高计算效率。理论模型证明此方法可行,实际资料处理效果明显。

The ordinary VSP imaging method is to use VSP-CDP conversion or Kirchhoff migration, which has issues of poor amplitude conservation and low imaging precision. The 3-D VSP wave equation depth migration in mix domain is to image the VSP reflection P-wave directly in depth domain and use Fourier method step by step to extrapolate wavefield in mix domain, that is to carry out phase-shift of wavefield in f-k domain and to implement time-shift correction in frequency-space domain. The advantage of the method lie...