非均匀弹性介质地震波场伪谱法正演模拟

基于一阶速度—应力弹性波波动方程,利用傅里叶变换将空间导数变换到频率域求解,对介质波场进行正演模拟。本文结合实际勘探中可能存在的地质问题,设计了多种地质模型,包括背斜模型、向斜模型、透镜体模型和断层--侵入体模型等,进行了伪谱法地震波场正演模拟、合成地震记录的实现,并分析了其波场动力学变化特征。结果表明,应用伪谱法对复杂模型的模拟有较高的精度和可靠性,可直接用于辅助地震野外工作设计、反演解释和资料解释等工作。

Inhomogeneous elastic medium seismic wave forward simulation by pseudo- spectral method

Based on first order velocity- stress wave equation，and using the Fourier transform，in which spa- tial derivatives are computed by multiplication in the frequency domain，the authors simulate the wave field of the medium． Combining with geological problems probably existed in practical exploration，the authors designed many geological models，such as the anticline- ，syncline- ，lens- ，and fault- intrusion models，and realized pseudo- spec- trum forward modeling， made synthetic seismogram and analyzed the characteristics of wave field dynamics． The re- sults show that the pseudo- spectral method has high accuracy and reliability． It can be directly used to assist in the assistance of seismic field work design，and the inversion and data interpretation．