The numerical simulation of visco-acoustic media using the high-order Fourier finite-difference method can reflect the seismic response of high-dip strata with geo-absorption effects more accurately.It can adapt to any lateral speed changes and suppress the dispersion and background noise at large dip angles caused by the finite-difference method.The migration precision of the high-dip strata depends on the determination of the constant coefficient of the difference operator and the calculation of the order.In this study,the gradient descent method was used to optimize the high-order finite-difference correction item in the Fourier finite-difference operator.According to the optimization results of the relative errors and constraint coefficients,the approximation effects of higher-order equations were achieved without increasing the order of the equation and then were expanded to viscoelastic media.Using the designed model,it can be concluded that the proposed method is applicable to the forward simulation of the strong spatial variable speed media with absorption and attenuation effects and has high calculation accuracy and efficiency.Accurate seismic numerical simulation of complex geological structures further confirmed the effectiveness of this method.
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