反转构造模型的地震波模拟及成像

为了检验由地震剖面解释得出的反转构造的可靠性,探讨反转构造地区在地震数据采集,处理中应采用的有效方法,设计了一个典型的反转构造模型－突起构造。以该模型为基础,针对复杂构造地震波模拟中常见起源频散严重、人为边界反射吸收不理想两个问题,应用高阶差分法以及一种新的边界吸收条件,对反转模型进行了地震波场数值模拟和深度偏移成像处理。采用中心放炮两边接收的观测方式,共模拟了185炮地震记录。研究表明,波动方程高阶差分法是模拟复杂构造模型中地震波传播的有效方法,除了近于直立的断层因难以接收到其反射波而较难成像外,其余的反转断层及其组合在理论上是可以通过合适方法（如Fourier有限差分深度偏移）较好地成像的。

Seismic Wave Simulation and Imaging of an Inversion Structure Model

Tectonic inversion could usually result in the complication of structure styles in that either pre-existing faults are reactivated or new reverse faults formed during the inversion stage. Correct seismic interpretation of inversion structures is fundamental for the study of inversion tectonics. The validity of seismic interpretation in inversed basins is related to the original available data and the appropriate processing methods. In this study, we used the pop-up structure as an inversion structure model for the seismic wave simulation and imaging. High-order difference method was applied to reduce the numerical dispersion and a new kind of absorbing boundary condition was adopted in the simulation. Mid-point shot was used in the simulation with a total of 185 shots recorded. Depth-migration imaging was then applied on the zero-offset profile to achieve a high quality seismic profile that is comparable to the original model. The simulation and imaging results demonstrated that high-order difference method is an effective approach for the simulation of seismic wave propagation in complicated structures. With proper imaging methods, such as Fourier finite difference method, most inversed structures can be recognized from seismic profiles.