Implementation Methods And Techniques Of Kirchhoff-type Remigration

Seismic remigration is a kind of seismic reflection imaging technique.Its aim is to calculate the migrated image fields in another velocity field from the migrated image fields in one velocity field.So far,there are two kinds of mathematics theory to realize remigration,namely differential operator theory and integral operator theory.Based on the theory of differential operator,the migrated image of reflection surface is considered as a kind of wave.Based on the assumption of homogeneous media,a partial differential equation is established to describe the wave propagation process.By solving the partial differential equation,the remigration imaging is realized.Based on the Kirchhoff migration operator and the Kirchhoff demigration operator,the remigration imaging is realized by changing the velocity field.The integral operator method is efficient and has strong adaptability to irregular data,which is mainly used in seismic velocity analysis.Therefore,it is important to study the remigration method of integral operator theory.There are two ways to implement the integral operator method,namely,namely the differential operator method and the integral operator method.The main problem for the Kirchhoff chained operator is the redundant computing.The chained operator is the combination of diffraction-stack migration and isochron-stack demigration,and the realization method is simple,so this paper chooses the chained operator to realize the integral operator theory remigration imaging.The main problem for Kirchhoff single-stack remigration is the determination of the integral surface.In order to improve the efficiency and not to calculate the integralsurface of the Kirchhoff single-stack operator,this paper puts forward a method to deal the problem by stacking the input data and then smearing it out directly in the output space.Because the aperture,aliasing and migration velocity are the important factors affecting the imaging quality of the chained operator,the above factors are analyzed in this paper.Given the fact that the flexibility and efficiency of Kirchhoff remigration on the imaging,this paper implements the depth domain Kirchhoff remigration imaging method,analyzes the main factors influencing the imaging result.The numerical experiment results prove the effectiveness of the Kirchhoff remigration theory,and prove that the new method for the implementation of Kirchhoff remigration is practical.