实现最佳零炮检距地震照明成像——CRS叠加之几何阐述

零炮检距剖面是地震反射成像过程中重要的中间成果，常规处理中的共中心点（CMP）叠加的目的正在于此。当地层倾斜时，CMP道集发生反射点弥散，CMP叠加无法得到正确的零炮检距(ZO)剖面。在这种情形下，只有实施NMO/DMO叠加或沿着共反射点（CRP）轨迹进行叠加才能达到偏移到零炮检距（MZO）的目的。根据共反射面元（CRS）叠加理论，CRS叠加面是反射点附近一个邻域内CRP轨迹的集合，所以沿CRS叠加面应能得到最好的零炮检距剖面。以几何描述的方式，在常速介质假设下通过图示定性描述CRP与CRS叠加之间，NMO/DMO叠加、叠前深度偏移（PreSDM）与CRS叠加之间的区别与联系。

To attain zero-offset imaging by the best seismic illumination:A geometrical view of CRS stacking

Zero offset(ZO) section, which is just the goal of CMP stacking in conventional processing, is an important intermediate result in seismic reflection imaging. We cannot get correct ZO sections if oblique layers are imaged. In this case, only by NMO/DMO stacking or stacking along common reflection point(CRP) trajectory can one attain correction ZO sections. According to theory of common reflection surface(CRS), CRS stacking surface is a set of CRP trajectories in the vicinity of a reflection point, stacking along CRS will therefore yield best ZO sections. In this paper we discuss the difference and relationship between CRP and CRS stacking, NMO/DMO stacking, as well as pre stack depth migration(PreSDM) and CRS stacking in a geometrical viewpoint and on the hypothesis of constant velocity media.