JSEJournal of Seismic Exploration0963-0651AccScience PublishingArticleOptimization of staggered grid finite-difference coefficients based on conjugate gradient methodhttps://geophysical-press.com/journal/JSE/articles/72JINKEJIE,HUANGJIANPING,ZOUQIANG,WANGZIYING,TONGSIYOU,LIUBIN,HUZIDUO20223112022-02-01The implementation of difference coefficients optimization strategy can effectively suppress numerical dispersion and improve the modeling accuracy. The conventional difference coefficients calculation method based on Taylor-series Expansion exists serious numerical dispersion. In this paper, we derive a new dispersion error function from the dispersion relation, and the optimal difference coefficients are obtained iteratively by using the conjugate gradient method, thus a staggered-grid difference coefficients optimization method based on the conjugate gradient is developed. We compare dispersion curves, snapshots and single shot records using low-velocity model, high-velocity model and Marmousi model, the results show that the new method can effectively reduce the numerical dispersion compared with the difference coefficients of the conventional Taylor-series Expansion method. The 8th-order optimized difference operators can achieve the modeling precision of 12th-order Taylor-series Expansion difference operators, which can effectively save calculation time and internal storage. The optimization method performs well for both simple model and complex model forward modeling.finite-difference, staggered grid, numerical dispersion, difference coefficients, conjugate gradient

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