【摘要】 地震波数值模拟是解决地震正反演问题的重要手段和了解地下地质构造的有力工具。从波动方程出发建立一阶速度-应力方程组,用Taylor级数和交错网格差分技术对方程组进行高阶差分离散,避免了直接对波动方程二阶导数进行差分带来运算量大的问题;采用特征分析法处理边界问题,对边界反射进行很好的吸收。文中给出了相应差分精度的稳定性条件,并用高阶交错网格有限差分法对非均匀介质模型进行了数值模拟。计算结果表明,该方法具有较高的稳定性和精度,适合于复杂介质的弹性波场模拟。更多还原

【Abstract】 Seismic wave numerical simulation was an important means to solve the problem of the seismic inversion and also a powerful tool to recognize the underground geological structure. One-order velocity-stress equations were established based on the elastic wave equation. The velocity-stress equations were replaced with high-order finite-difference by using Taylor series and staggered grid technique,by which the large computation problems resulted from differentiating the two-order derivate in the wave equation were avoided. Feature analysis method was adopted to solve boundary condition. The boundary reflection was absorbed effectively by this method. The stability conditions of the differential accuracy were given. The geology models were numerically simulated by high-order staggered grid difference method. The results show that the method is of high stability and accuracy,and suitable for elastic wave simulation of complex media.更多还原