一种倾角时差校正和叠前成象方法

本文从测量射线参数出发进行反向射线追踪,导出倾角时差校正（DMO）的公式。经过DMO后,可以从一组等炮检距剖面得出共分角线点道集。用于对这些道集进行叠加的速度值与界面倾角无关。对经过DMO的资料的等时切片进行叠前成象（PSI）,就可以把分布在圆上的绕射能量沿圆弧加起来,并放在圆弧上对应于最大炮检距的位置。经过这两种处理,再应用标准的速度分析和叠加方法,就可得出偏移后的剖面。这两种处理均与速度无关。最后用物理模型试验说明了DMO和PSI的效果是好的。

A METHOD OF DMO AND PSI

Dip moveout has been approached in several ways. The present investigation starts from yet another point: the measurement of ray parameters and their use in inverse ray tracing. After DMO, the offset sections can be sorted into Common-bisector-point gathers. The velocity V for stacking these gathers is not dependent on dip angle.Prestack imaging on constant-time slices of the data, after dip moveout has been applied, in which diffractions appear as circles, add data along these circles, and plot the sum at the largest offset point of the circles. After both processings, a standard velocity analysis and stacking algorithm produce a migrated section. Both processings are independent of velocity. The effect of DMO and PSI is shown by tests with physical model data.