VSP多道迭代递归滤波波场分离及应用

为了适应VSP不等间距观测系统采集数据的波场分离的需要,F.Aminzadeh提出了迭代滤波方法。但是此法是以不含噪音为前提,因此方法的应用受到限制。本文在此基础上提出一种VSP多道迭代递归滤波分离波场的方法.给出新的褶积算子,对噪声不加限制。新的褶积算子可以利用道间的直达波时差,从而增强了方法的抗噪能力。对于任意一个VSP记录道(不考虑边道),利用新的褶积算子均可以利用其两边相邻记录道的波场来求出上、下行波场,因而提高了波场分离的精度。未考虑道间能量弥散。该法与中值滤波相比,不存在边道效应;与二道滤波相比,抗噪能力较强。

A method for VSP wave field separation using multitrace iterative recursion filtering,and its application

F. Aminzadeh advanced iterative filtering method in order to separate the VSP wave field recorded by unequally-spaced receivers. His method is based on the premise that there is no noise,so its application is limited. Hence,a method for noisy VSP wave field separation using iterative recursion filtering is presented, which introduces new convolution operator. The new eonvnlution operator uses intertrace moveouts of direct wave to enhance the ability to attenuate noises. With the aid of the new convolution operator,the upgoing and downgoing wave fields of any VSP trace other than side trace can be obtained by adopting the wave fields of its two close neighbour traces, so that the accuracy of wave field separation is improved. Inter- trace energy dispersion is not considered here.This method has no such side-trace effect as in median filtering, and brings stronger noise-resistant ability than two-trace filtering method.