非均匀粘弹介质中有限元地震数字模型

Finite-element numerical modeling for seismic wave in nonuniform viscoelastic medium

本文讨论了粘弹介质的地震波响应。假定介质为块状,且块中纵,横波速度及密度、品质因数横向分段线性连续变化。在此条件下,给出了粘弹波动方程制作时间剖面的数学模型,导出了相应的有限元方程并给出其计算方法(包括刚度矩阵、阻尼矩阵)。模拟某实际水平叠加剖面的仿真结果,展示了该方法的效果和水平。

Seismic response in viscoelastic medium is discussed here. The assumption is made that P-wave velocity, S-wave velocity, density and Q factor show lateral piecewise linear continuous variations in block media. Under the above assumption, mathematical model for making seismic time section with the use of viscoelastic wave equation is developed; the relevant finite-element wave equation is derived; and the calculation method for the finite-element equation, including stiffness matrix and damping matrix, is given in the paper. The effect of simulating a real horizontal stack section shows that this method is feasible.