有限差分二、三维速度层析成象

FINITE-DIFFERENCE 2-D AND 3-D SEISMIC TRAVELTIME VELOCITY TOMOGRAPHY

介绍了利用有限差分方法进行地震走时资料速度反演的基本原理与方法,并对理论模型进行了正演和反演。然后对唐山滦县的Pg 波三维资料和菏泽—林县—长治的二维Pg 资料分别进行了三维和二维反演,反演结果与浅层地质资料较好吻合,由于反演是采用不用矩阵运算的反投影方法,可以实现稠密采样,这为我们提供了一种较好的得到高精度浅层速度的办法,为深部结果的反演提供了可靠的浅层速度资料。

This paper presents the principle of traveltime velocity tomography using Finite Difference method.Two real data inversion examples from pg wave data are given.One example is three dimensional velocity structure of Tangshan Luanxian earthquake area.Another example is Heze Linxian Changzhi two dimensional velocity structure.There is much correspondence between velocity of inversion results and shallow geological structure.