共反射点时距方程与变速DMO

目前使用的常规DMO数据处理方法忽略了速度的影响,认为DMO处理对速度不像全偏移那样敏感。但实践证明,在某些情况下作DMO处理必须考虑速度的影响,否则会给地震成像带来严重的不良后果。本文从共反射点时距曲线方程出发,导出了类似于常速DMO公式的变速DMO公式(与Hale等称之的squeezingDMO相类似)。该方法是对常速DMO方法的一种修正,计算效率与常途DMO相当,但处理效果要好于常途DMO方法。理论与实际资料的处理结果表明,该方法对速度随深度变化地区的大倾角反射成像是十分有效的。

CRP gather time-distance equation and variable velocity DMO

Ordinary DMO processing methods neglect the influence of velocity because some people think that DMO processing is less sensitive to velocity than full migration processing. As a matter of fact, under certain circumstances, DMO processing must consider velocity effect to avoid bad result in seismic data image.Variable velocity DMO formula which is analOgous to constant velocity DMO formula and Hale's squeezing DMO is derived from the time-distance equation of CRP gather data- The method is a revised version of constant velocity DMO; and it is equivalent to constant velocity DMO in computation efficiency, but superior to constant velocity DMO in processing result.Theoretical and real processing results show that the method is very suitable to the image of steep-dip seismic data in the area where seismic velocity varies with depth.