相移加校正叠前深度偏移及偏移速度分析

从理论上说，叠前深度偏移是众多的地震资料偏移成像方法中最精确的偏移方法。本文针对纵横向变速的复杂地质模型，采用相移加校正方法在ＣＳＰ道集上邮二维叠前深度偏移。该 以相移法煤中上局部速度变化因子校正，并用自动统计子波方法确定震源函数形式，因此该法既不受地层倾角的限制，又可解决复杂构造的横向变速问题。

Migration velocity analysis and prestach deptk migration by phase shift plus correction

Theoretica1ly, prestack depth migration is the most correct one of seismic mi-gration methods. Phase shift plus correction can be used to achieve 2-D prestackdepth migrati0n of common-shot seismic data in the case of complicated ge0logicmodel in which velocity varies laterally and vertically- This method includes bothphase shift and correction of local velocity variation factor, and determines sourcefunction by automatic wavelet statistics. As a result, this method is not 1imited informati0n dip angle, but copes with the azimutha1 vel0city variati0n in c0mplicatedgeol0gic structures. Theoretical and real processing results show that this methodbrings good data processing accuracy and high signal/noise ratio-Velocity model causes direct influence upon depth migration effect. Our inter-active batch velocity estimation offers accurate migration velocity model. The esti-mation can fast bring accurate equivalent migration velocity and interval velocity be-cause it is based on prestack depth migration and uses global optimization geneticalgorithm. By using the vel0city model constructed with this method, we can 0b-tain the depth migration section whose seismic horizons coincides with drilled ge0-logic horizons desirably. Theoretical and real processing results prove this methodvery feasible.