等效偏移距方法及应用  

Equivalent offset method and its application

作　　者：王伟[1] 尹军杰[2] 刘学伟[3] 赵俊猛[1] 王赟[2] 黄英[1] 

机构地区：[1]中国科学院青藏高原研究所,北京100085 [2]中国科学院地质与地球物理研究所,北京100029 [3]中国地质大学(北京),北京100083

出　　处：《地球物理学报》2007年第6期1823-1830,共8页Chinese Journal of Geophysics

基　　金：中国地质调查局科研项目(20002010002146);中国科学院知识创新方向性项目(kzcx3-sw-143)资助

摘　　要：当勘探目标地质构造复杂、地层倾角较陡或岩性横向突变时,在地表接收到的反射信号较弱、信噪比较低,甚至接收不到反射波,常规偏移成像方法对这类数据很难精确成像,因此可以考虑基于散射理论的等效偏移距方法来成像.该方法分两步进行:第一步是抽取共散射点道集;第二步是对共散射点道集进行克希霍夫积分偏移.文中数值模拟及实际资料的实例表明,该方法在复杂地质目标及低信噪比地震资料的成像处理中具有一定的实用价值.When the geologic structure is complex, the dip of the layer is large, or the lateral change of lithology is abrupt, the reflection waves are weak with a low signal-noise ratio, even unable to be received. Routine imaging method is invalid for such data, but the equivalent offset migration based on scattered waves is viable. The method consists of two steps： the first is a gathering process that forms common scatter point gathers; the second is a focusing process that applies a simplified Kirchhoff migration on the CSP gathers. Based on examples of numerical simulating and sea data, the paper shows that the method of scattering image is widely and practicably valuable in processing of complicated geologic structure and low signal-noise ratio seismic data.

关 键 词：克希霍夫积分 共散射点道集 等效偏移距 信噪比 

分 类 号：P631[天文地球—地质矿产勘探]