井间地震层析成象中地震射线的求取

DETERMINATION OF SEISMIC RAY IN CROSS-WELL SEISMIC TOMOGRAPHY

在井间地震层析成象中,地震射线的求取是项很重要的工作。通常有两种主要的方法:射线追踪和求最短路径。考虑到井间地震层析成象的特殊性,本文认为最短路径方法是更为合适的选择。但是,求取最短路径的一般性算法过于复杂,而且很费时。为了改进算法,文中对此进行了先验假定,进而提出了一个简化的计算格式,并在最后给出了几个算例。

In cross-well seismic tomography, to determinate the seismic rays is a very important thing. To solve the above-mentioned problem,there are ,in general,two major methods should be adopted,e. g. ,the ray-tracing and the shortest ray-path determination. With the specialities of the cross-well tomography taken into consideration,the authors hold that the method of shortest-path wouldbe the belter choice. But owing lo the general algorithm for the shortest-path calculation is too complicated and is timeconsuming,hence, in order to make the calculation simpler and time-saving,a simplified calculating format was thus suggested on the basis of a priori assumption. Examples were given at the end of the paper.