标题： 一种用于一阶弹性波动方程建模的非平衡交错网格有限差分格式 显示英文标题

标题： A non-balanced staggered-grid finite-difference scheme for the first-order elastic wave-equation modeling

摘要： 我们引入了一种高效且准确的交错网格有限差分(SGFD)方法来求解二维弹性波方程。我们采用耦合的一阶应力-速度公式。在SGFD方法的标准实现中，使用相同的SGFD算子来近似空间导数。然而，我们提出了一种基于混合SGFD算子的数值方法，这种算子在与均匀SGFD算子相比时，效率更高且精度相似。我们将所提出的方法称为非平衡SGFD数值方案，这意味着将高阶SGFD算子与二阶SGFD算子结合。非常仔细地关注了SGFD算子系数的推导。通过色散分析证明了所提出方案的正确性。通过SGFD建模实例，我们验证/展示了所提出的非平衡算子在计算成本更便宜的情况下，与更昂贵的平衡SGFD方法相比，具有相似的精度水平。 显示英文摘要

摘要： We introduce an efficient and accurate staggered-grid finite-difference (SGFD) method to solve the two-dimensional elastic wave equation. We use a coupled first-order stress-velocity formulation. In the standard implementation of SGFD method the same SGFD operator is used to approximate the spatial derivatives. However, we propose a numerical method based on mixed SGFD operators which happen to be more efficient with similar accuracy in comparison to uniform SGFD operator. We refer the proposed method as the non-balanced SGFD numerical scheme which means combining high-order SGFD operators with second-order SGFD operators. A very care attention is directed at the derivation of the SGFD operator coefficients. The correctness of proposed scheme is proven by dispersion analysis. Through SGFD modeling examples, we verify/demonstrate that the proposed non-balanced operator offers a similar level of accuracy with a cheaper computation cost compared to the more expensive balanced SGFD method.