VTI介质井间地震高斯束正演数值模拟

Gaussian beam forward numerical simulation of cross-well seismic in VTI medium

为了研究垂直横向各向同性(VTI)介质井间地震中,地震波的传播方向及波场特征,采用高斯束方法对复杂构造进行波场正演模拟。分析VTI介质中地震波的群相关系,并提出群相数据库思想来解决地震波在VTI介质中传播的方向和速度问题,改善了波场正演模拟的算法。同时高斯束正演方法不仅能够解决复杂构造的盲区问题,且其动力学特征更能反映各向异性介质对地震波传播的影响。较VTI介质频率-空间域弹性波正演模拟方法,正演结果一致且计算效率高,能有效分辨地震波场特征,为地震数据的处理与解释提供了借鉴。

The Gaussian beam method is used in wave tield forward modeling in complex structure, in order to study the di-rection of seismic wave and the wave tield characteristics in vertical transversely isotropic（ VTI） medium in cross - well seismic. The group -phase relations of seismic wave are analyzed in VTI media, the group -phase database thought is put forward to solve the problems of direction and velocity of seismic wave in VTI media, and the algorithm of wave tield forward modeling is improved. At the same time, Gaussian beam forward modeling method is not only solving the problem of blind area of complex structure, and its dynamic characteristics can reflect the anisotropy medium effects on seismic wave propagation. Compared with elastic wave forward modeling method in frequency -spatial domain in VTI media, the forward modeling results are con-sistent and the computational efficiency s higher. The characteristics of seismic wave field can be effective separation. Themethod provides accurate basis for seismic data processing and interpretation.