Abstract:In Sichuan Basin,the near-surface is very complex.Targets are deeply buried (more than 7000m).Weak reflections,low frequency,and distorted wavelet lead low resolution of deep imaging,and the thin bed identification becomes very difficult.In order to reduce the influence of absorption on prestack depth migration,the Q prestack Kirchhoff depth migration provided by GeoEast System is used.By introducing complex velocity and complex travel time,this prestack depth migration performs amplitude compensation and phase correction strictly according to the amplitude attenuation and dispersion effect caused by the formation absorption of the wave field,which can effectively improve the fidelity and resolution of deep imaging.Based on our application,the Q prestack Kirchhoff depth migration can significantly improve the amplitude relationship,widen the frequency band,and enhance the migration imaging resolution compared with conventional prestack Kirchhoff depth migration,which makes thin beds much easier to be identified and tracked.
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