摘要 本文对 Eduardo L Faria和 Paul L Stoffa提出的在横向各向同性介质中计算地震波初至旅行时的算法做了改进。利用地震波传播的互换原理 ,将算法推广到用于计算反射纵波和反射转换横波的旅行时。本文提出的算法采用差分网格剖分介质计算区域 ,对于介质参数发生突变或介质分界面变化复杂的情况都具有很好的适用性 ,计算结果不存在阴影区 ,且具有较高的精度。本算法可以计算各向同性介质和横向各向同性介质中直达波、反射波和透射波的旅行时 ,并用来模拟地面地震勘探、VSP、井间地震。
Abstract:Eduardo L Faria and Paul L Stoffa's algorithm for computing the first breaks of seismic waves in transversely isotropic medium may be improved reasonably.With the use of reciprocal principle in seismic wave propagation,the algorithm may be used to compute the travel times of reflected compressional wave or converted shear wave. The improved algorithm,taking difference grid medium,is very adaptable to both sudden change of medium parameters and complex interface variation,so that it brings accurate result,without blind area in the final result. The improved algorithm is applicable to the estimation of the travel times of direct,refleeted and transmitted waves in isotropic medium or transversely isotropic medium;besides,it may be taken to model surface seismic exploration,VSP and borehole seism.