【摘要】 应用双变网格(空间及时间)方法可对复杂储层地震波场进行精细模拟,且具有较高的计算效率,但空间变网格方法的缺点是在两种网格的边界处会引起数值噪声。为了更准确地对局部复杂构造进行数值模拟,本文从理论分析和数值模拟结果两方面对空间变网格的插值算法和变系数算法及变时间步长方法进行了定量研究和对比分析。通过对以上方法的定量误差分析,进而确定这些算法的适用范围。在数值模拟时通过选择合适的方法和参数,可以保证对微弱波场异常的模拟精度。更多还原

【Abstract】 Dual-variable grid algorithm can be applied on fine simulation of wave fields of complex reservoirs with high calculation efficiency.However,with the variable space grid and variable time step,numerical noises would be generated at the interface of different grids and steps.In order to obtain more accurate numerical modeling results on locally complex structures,quantitative studies and comparisons on varying-space grids with interpolation method and variable coefficient method are implemented by theoretical analysis and numerical stimulation experiments.An error analysis of locally variable time step method is also conducted in this paper.Errors generated by each of the three methods mentioned above are then quantitatively studied to determine the application scope of each corresponding method.And thus the simulation accuracy can be guaranteed in case of weak anomaly of wave field by choosing appropriate method and parameters.更多还原