Kirchhoff Dynamic Focused Beam Migration

Kirchhoff beam migration is one kind of beam migration methods.In this algorithm,reflection data is divided into different beams,and each beam will be migrated to achieve the final result.Kirchhoff beam migration can calculate muti-arrival traveltime,which has the advantages of high precision and high efficiency.However,as the ray propagating,the beam width increases too fast,and it might reduce the calculation precision of grid nodes’ attribute information.To solve the difficult problem,the regular beam operator is replaced in Kirchhoff beam migration in this paper,we propose the Kirchhoff dynamic focused beam migration.The following achievements have been gotten.(1)Dynamic focused beam propagate operator has been applied in Kirchhoff beam migration to control the beam width.(2)A new method of computing the weight function is given to ensure the final imaging quality.(3)Kirchhoff dynamic focused beam migration is changed to adapt to the rugged topography.(4)Kirchhoff dynamic focused beam migration is also changed to adapt to the seismic data obtained from the anisotropic media.Several seismic numeral models and actual seismic data are adopted to verify the imaging capability of Kirchhoff dynamic focused beam migration.It shows that the new method has a strong imaging capability,even when it is adopted for seismic data under the rugged topography condition or anisotropic media,it also can obtain imaging results.