广义有限差分地震波场数值模拟方法能够适应起伏的地层界面，消除起伏界面造成的阶梯状散射现象，提高正演模拟的准确性。而使用时间二阶广义有限差分法求解波动方程时，由于时间差分精度低，时间采样间隔较大时往往会产生时间频散，影响正演模拟的精度。研究了标量波方程时间四阶广义有限差分正演模拟算法及其稳定性条件和频散特性，通过将时间四阶偏导数转嫁到空间偏导数项上实现时间四阶精度差分，时间频散得到有效的压制。此外相对于时间二阶广义有限差分法，时间四阶广义有限差分可以适应较大的时间采样间隔，一定程度上减少计算量。实验结果表明，所提出的算法能有效压制阶梯状散射和时间频散，具有更高的计算精度，将其应用于逆时偏移，可以获得高质量的成像剖面。

The generalized finite difference method for seismic wavefields numerical simulation is capable of adapting to undulating stratigraphic interfaces, eliminating the staircase scattering effect caused by such interfaces, and enhancing the accuracy of forward modeling. However, when the second-order generalized finite difference method is used to solve the wave equation, low temporal accuracy can lead to temporal dispersion at larger time intervals, affecting the precision of forward simulation. A fourth-order generalized finite-difference forward modeling algorithm for the scalar wave equation was studied, along with its stability conditions and dispersion characteristics. By transferring the fourth-order time derivative to the spatial derivative term, fourth-order accuracy in time was achieved, effectively suppressing temporal dispersion. Compared to the second-order generalized finite-difference method, the fourth-order approach allows for larger time intervals, thereby reducing computational costs to some extent. Experimental results demonstrate that the proposed algorithm effectively mitigates both staircase scattering and temporal dispersion, yielding higher computational accuracy. When applied to reverse time migration, it produces high-quality imaging profiles.