Boundary-Volume Integral Equation Numerical Modeling for Complex near Surface

详细信息   

• 责任者：Guan Xizhu (Institute of Geology and Geophysics ; Chinese Academy of Sciences ; Beijing 100029 ; China) ; Fu Liyun
• 刊名：Chinese Journal of Geophysics
• 出版年：2011
• 卷期：54(9)
• 关键词：地震勘探 ; seismic exploration ; 边界元法 ; boundary element methods ; 波动方程 ; wave equation
• 页码：p.2357-2367
• 图表：illus., 19 refs.
• 分类号：1600
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

摘要

Complex near surface causes the anomalous variation of the amplitude and phase of seismic reflection signal from deep structures, and it is the most important factor to degrade the quality of seismic data. In this paper, we use the boundary-volume integral equation technique to simulate the seismic wave propagation in the complex near surface structure by solving the wave propagation equation with complex near surface condition. In the boundary-volume integral equation technique, the boundary element method can simulate irregular surface and geological structure for seismic wave propagation, and the volume element method can simulate the effect of the heterogeneous medium in low subweathered zone for the seismic wave propagation. Compared with other numerical simulation methods, the main advantage of the boundary-volume integral equation technique is its accurate geometric description of irregular surface and interface to simulate the boundary scattering waves by the free surface; it explicitly applies the continuous boundary conditions of the complex near surface to implement the semi-analytical numerical simulation; it can deal with the complex near surface structure piecewise and effectively simulate the scattering body wave field caused by the inhomogeneous medium under the complex near surface. Numerical results show that the method is practical and effective.