周期性粗糙界面地震绕射波数值仿真与分析

Numerical Simulation and Analysis of Seismic Diffraction Waves with Periodic Rough Interface

数值仿真作为勘探地震学中研究地震波的重要手段,为野外实际数据采集和处理提供有力的科学依据。作为反射地震成像的重要补充,绕射波可以提高成像分辨率。因此,有效识别和确认数据中绕射波成分显得尤为重要。以正弦形粗糙界面为研究对象,采用谱元法数值模拟技术,分析绕射波传播规律,确定绕射波空间分布特征。结果表明,地震波与正弦界面作用后产生不同阶绕射波,其运动学特征满足光栅方程,且高阶绕射波具有更加严重的角频散。此外,仿真结果对学生深入理解绕射波对地震数据处理的影响具有重要的辅助作用。

As an important means of studying seismic waves in exploration seismology,numerical simulation provides a powerful scientific basis for field data acquisition and processing.As an important supplement to reflection seismic imaging,diffracted waves can improve the imaging resolution.Therefore,it is particularly important to effectively identify and confirm the diffracted wave components in the data.Taking the sinusoidal rough interface as the research object,the spectral element method(SEM)is used to analyze the propagation law of diffracted waves and determine the spatial distribution characteristics of diffracted waves.The results show that different order diffraction waves are produced after the interaction between seismic waves and sinusoidal interfaces,and their kinematic characteristics satisfy the grating equation,and the higher order diffraction waves have more serious angular dispersion.In addition,the simulation results play an important auxiliary role in students'in-depth understanding of the influence of diffracted waves on seismic data processing.