地震速度谱在精细深度图制作中的应用

The application of seismic velocity spectrum in making depth map

1. 中国地质大学,北京 100083;2. 中国石化胜利油田物探研究院,山东东营 257022

China University of Geosciences, Beijing 100083, China

常规制图方法是用一个区域平均速度或用井点平均速度进行时深转换,这在构造较平缓地区,可以满足勘探精度要求。对于构造变化剧烈,即地层纵、横向速度变化很大的地区,用常规制图方法作出的构造图就会存在较大的误差,难以满足精细油藏描述的要求。因此,提出了用层位约束拾取速度谱,在求取平均速度后用井点平均速度进行校正,再进行时深转换的方法。将该方法应用于山东胜利油区曲堤油田,大大提高了深度图的精度,减少了深度误差。

The average velocity is used in time-depth con-version in traditional methods of making depth map.It is enough for accuracy in flat areas. However, inareas of rapidly lateral velocity changes, the resultedstructural maps may contain relatively large errors.Method introduced in this paper is that average ve-locities are calculated by velocity spectra, and correc-ted by average velocities of well points and horizons.Depth map is then made using time-depth conver-sion.The method was tesified in Qudi oilfield.