VSP地震干涉测量的稳相分析与高陡构造成像

Stationary phase analysis of seismic interferometry applied to VSP data and high-angle structure imaging

地震干涉测量(SI)是近几年勘探地球物理领域研究的一个热点方向.首先,在高陡断层模型的基础上,利用稳相分析解释垂直地震剖面(VSP,Vertical Seismic Profile)地震干涉测量的物理含义,分析虚假同向轴产生的原因,更重要的是找到地震干涉测量实现波场转化的主要贡献项;其次,利用地震干涉测量实现VSP向单井剖面(SWP,Single Well Profile)波场转化,观测系统转换到井中,离目标地质体更近,实现高陡构造成像;最后,将该成像结果与传统地面地震勘探在高陡构造成像质量方面进行对比,得出该方法可以有效提高高陡构造成像精度的结论,为复杂高陡构造成像提供了新的思路.

Seismic Interferometry（ SI） has been a hot issue in geophysics exploration in recent years. Firstly,on the base of a highangle fault model,the paper utilizes Stationary Phase Analysis to investigate the physical interpretation of SI and analyzes the origin of spurious events. More importantly,we find the essential terms that contribute towavefield transform. Secondly,SI is used to achieve VSP（ Vertical Seismic Profile） to SWP（ Single Well Profile）wavefield transform. By this transform,geometry is reconstructed in the well,gets closer to the structure targets near well and obtains satisfactory structure imaging. Finally,we compare this imaging results with traditional surface seismic exploration on steep structure imaging,and get the conclusion that this method can effectively improve the imaging precision of high-angle structure. It provides a new way to image complex steep structures.