Seismic Data Imaging Of "Bohai Bay-dagang" Model And Modeling Experiment Research And Application

Based on the current situation of exploration,although the large-scale integrated seismic data provide favorable data support for the basic geological research,it still can not meet the needs of fine research in signal to noise ratio,amplitude variation and resolution,etc.Most complex geological problems are manifested in seismic processing data as resolution and imaging accuracy.For complex structures,the current conventional migration method often has multiple solutions,while prestack depth migration can more accurately locate the reflected wave.Prestack depth migration also reduces the impact of steep dips and rapid changes in velocity.With the increasing complexity of exploration,the advantages of prestack depth migration are fully revealed.This paper mainly carries out theoretical and applied research on prestack depth migration method.First of all,based on the high-precision requirement of complex structures imaging in Dagang exploration area,in the seismic data imaging experiment of "Bohai Bay-Dagang" model,three classical prestack depth migration methods are analyzed.Then,combined with the needs of velocity modeling and the consideration of efficiency cost ratio,the migration method selection principle considering both efficiency and practicability is formed.Secondly,according to the high requirement of prestack depth migration on velocity modeling,this paper divides the velocity modeling process into three key technical links: initial model establishment,model optimization,and offset correction,and then summarizes the key quality control points of high-precision velocity modeling.Finally,through the practice of prestack depth migration in Qianmiqiao area,the conclusion of the above research is verified in practice,and the expected processing effect is achieved.