地震层位约束下的速度分析技术

Velocity Analysis Technology with Seismic Horizon Constraint

在地震资料处理中速度是一个重要参数,速度的准确与否将直接影响剖面的叠加效果。传统的速度分析方法所拾取的速度谱点在时间方向上比较稀疏,解释的速度点不容易与地震层位对应,容易漏掉一些速度的高频信息,且速度低频背景不容易控制,受人为因素及经验因素影响较大,其精度已不能满足精细勘探的要求。从而提出了地震层位约束下的速度分析技术,通过拾取地震层位,利用关键速度控制点的速度进行沿层速度内插得到初始速度场,再进行沿层交互速度分析,提高速度分析精度。该技术在塔东地区地震资料的精细速度分析中的应用效果表明,目的层的构造形态得到落实,弱层的成像效果也得到了明显改善。该技术对于信噪比低、构造复杂地区的速度分析具有借鉴意义。

Velocity is an important parameter in seismic data processing,and is accuracy directly afeets section stack.Velocity spectrum point picked by traditional velocity analysis rmethods were sparse in time,therefore,interpreted velocity point was dificult to crrespond with seismie horizons.Some high-frequency veloeity infomation was probably to be lost,and low-frequency beckground of velocity was dificult lw be contelled and afeted dranatically by human and experience faclors.So lraditional velocily analysis could not salislty needs of sophisticated exploration for 8ccuracy.Therefore,velocity analysis technology under seismie horizon constraint was proposed.It picked seismie horizons,used veloity of critical velocity points to interpolate along interval velocity to get initial velocity field,did process interact velocity analysis along layens and improved velocity analyais aocuracy.The new technology has been applied to fine velocity analysis of scismic data in Tadong area.The result showed that stuctural form of target layens were fulFlled and imging of weak layers was enhanced obviously.It ofred reference for veloeity analysis in such areas of low signal to noise ratio and complicated stnuture.