Depth migration in the offset-aperture domain: Optimal summation

Imaging may suffer from migration noise and artefacts due to operator or data aliasing, truncated aperture or nonoptimal migrated weights. This noise can be essentially reduced by using an optimal aperture of the migration operator which includes mostly the specular energy and not the long "tails" of the migration operator. The paper proposes a way to compute an optimal aperture Kirchhoffmigration images in an automatic way. This is achieved by considering migrated common image gathers in the aperture-offset domain. In this domain reflections appear as concave-shaped events where the specular energy is concentrated in a vicinity of the apex position. Limiting the aperture by the apices vicinity, optimal migration images can be constructed. The method uses a matching pursuit technique for solving a minimization problem in the hybrid Radon space.