Method Study Of Wave-equation Prestack Depth Migration Based On Irregular Topography

Both the complex surface and the complex geological structure is a big issue that land seismic has faced. In order to deal with this question many people have done much study in this area and have got much usefull method. The mathod of wave-equation prestack depth migration based irregular topography can deal with the both complex surface and the complex geological structure at the same time.Reverse-time migration method can effectively suppress multiple wave, eliminate noise effects, and reverse-time migration with no limitation of imaging angle, which has the capability to make the target structure clearly and correctly imaged. Based on this, this paper study the prestack depth wave equqtion method directly at the irreglar topography, for all of those method the reverse time migration is the most key, at last we have all the migration method tested.There are five chapters in the thesis. Chapter one is about the review of the importance and history of wave equation prestack depth migration based on irregular topography. Chapter two is about the image method study in irregular topography area, mainly talk about many datuming correction methods,such as static correction, Kirchhoff, wave equation datuming, zero velocity method, wave field upward continuation and reverse time migration ect. Chapter three is about the research and the compare on the wave equation prestack depth migration algorithms, including the FXFD algorithms, SSF algorithms, the FFD algorithms, reverse time migration and so on. Chapter four is about the migration method model test, to reverse-time migration numerical analysis, verify the correctness of the reverse time migration.then we tested all the methods in this thesis on Marmousi model and SEG model. Chapter five is the conclusions. Throught the study, we can found that The mathod of wave-equation prestack depth migration based irregular topography is the just suefull method to deal with the seismic migration in dual-complexity aera. Comparison with other migration methods reverse time migration with no limitation of imaging angle, it has the capability to make the target structure clearly and correctly imaged. The numerical results shows that the best method in seismic image is the reverse time migration.