优化的时空域等效交错网格有限差分正演模拟

发布时间：2018-05-15 22:32

本文选题：数值频散 + 时空优化差分系数　；参考：《中国石油大学学报(自然科学版)》2017年06期

【摘要】：地震波有限差分数值模拟中,使用优化的差分系数可以有效地减少数值频散(相速度误差)。为了同时压制空间频散与时间频散,提出一种时空优化的等效交错网格有效差分正演模拟方法。采用以减少给定波数范围内所有传播方向的相对频散误差为目标函数,并借助牛顿法快速获取优化的差分系数。频散分析表明等效交错网格正演在低速介质中容易出现空间频散,在高速介质中高波数分量容易出现时间频散,数值模拟显示该方法既能有效地压制空间频散,也可以减少时间频散。Marmousi模型测试表明该方法适用于复杂地质模型的地震波场正演模拟。相比传统差分方法,该时空优化差分方法在不增加计算量的前提下,可以有效地提高数值模拟精度。
[Abstract]:In the finite difference numerical simulation of seismic wave, the numerical dispersion (phase velocity error) can be effectively reduced by using the optimized difference coefficient. In order to suppress both spatial dispersion and time dispersion, an effective forward modeling method with equivalent staggered grids is proposed. The objective function is to reduce the relative dispersion error of all propagation directions in a given range of wavenumber, and the optimized difference coefficient is obtained quickly by Newton method. The frequency dispersion analysis shows that the equivalent staggered grid forward modeling is prone to spatial dispersion in low speed medium, and the time dispersion is easy to occur in high wavenumber component in high speed medium. Numerical simulation shows that the proposed method can suppress spatial dispersion effectively. It can also reduce time dispersion. Marmousi model test shows that this method is suitable for seismic wave field forward modeling of complex geological models. Compared with the traditional difference method, this method can effectively improve the accuracy of numerical simulation without increasing the computational complexity.
【作者单位】：中国石油大学地球科学与技术学院;
【基金】：山东省重大创新工程(2017CXGC1608,2017CXGC1602) 中国科学院战略性先导科技专项(XDA14010303) 国际合作重点项目(41720104006) 国家油气重大专项课题(2016ZX05006-004,2016ZX05014001,2016ZX05002) 中央高校基本科研业务费专项(R1701023A)
【分类号】：P631.4

【相似文献】