摘要
RG线作为时深转换基准面的前提是 RG线等效于地表高程的平滑线。在以往以寻找构造圈闭为目的的勘探中 ,这种方法是可行的 ,原因如下 :1区域地表结构简单 ,RG线可近似为地表的平滑线 ,以地表的平滑线替代RG线的高程误差不大 ;2反射时间误差为几毫秒至几十毫秒 ,不会影响发现幅度较大的背斜构造。目前地震勘探以寻找低幅度构造、断层、以及砂体等构造—岩性油气藏为目标 ,要求地震资料从处理到解释都必须满足一定的精度 ,才能保证地震剖面解释成果的可靠性。在这种情况下 ,RG线作为地震剖面解释的基准面是否合适值得探讨。本文详细论述了 RG线与地表平滑线之间的关系 ,其目的是说明 RG线并不等同于地表高程的平滑线 ,以RG线作为地震剖面解释的基准面会影响对地下构造形态的解释精度。文中还说明了如何解决时深转换的基准面问题。
The precondition of RG line being as datum of time-depth conversion is that the RG line is equivalent to the smooth line of surface elevation.The method was feasible in former exploration of looking for structural trap.The reasons are follows:① the surface relief is simple in previous exploration area,RG line can approximately be as smooth line of surface,replacement of elevation of RG line by smooth line of surface makes little errors; ② the errors of reflection time are only a few ms or even scores ms,having no influence on discovery of anticline structure.Present seismic exploration puts high-resolution and high-precision as its object,so that can find out structural-lithological oil/gas reservoir,such as structure with lower amplitude,fault,fracture and sand body,which demands data (from processing and interpretation ) coming to some precision, so can ensure the reliability of interpretation of seismic section.In that cases,it is worth to consider whether the RG line is suitable for datum of interpretation of seismic section.The paper expounds in detail the relation between RG line and smooth line of surface.Its aims are showing the difference between RG line and smooth line of surface elevation,the negative influence on interpretation precision of subsurface structure if using RG line for datum of interpretation of seismic section and how to solve the datum of time-depth conversion.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2003年第1期35-37,57,共4页
Oil Geophysical Prospecting
