The effects of dip-limited Kirchhoff migration and F-K migration
Kun Liu, John C. Bancroft
Dip-limited migration is utilized in practice for the purpose of either decreasing the computational cost (e.g., Kirchhoff migration) or suppressing noise (e.g., Kirchhoff and F-K migration). Dip-limited F-K migration is a common F-K migration with an embedded dip filter, while the dip-limited Kirchhoff migration is implemented by limiting the aperture of migration operators. Either of these methods will cause a dip-filtering action and result in a dip-restricted output section. However, there are distinctions between the effects of dip-limited Kirchhoff and F-K migration. Dip-limited F-K migration has an exact dip-filtering effect on the migrated section, whereas the dip-limited Kirchhoff migration generates additional artifacts when the dip limit is less than the maximum dip on the desired output section. These artifacts are caused by the endpoints of the migration operators and become more obvious as the dip limit is decreased. A geometric explanation as well as a synthetic experiment is developed in this paper to help understand these effects.