Internal Multiple Attenuation by Kirchhoff Extrapolation

The fully data driven approach at the basis of 3D-SRME can be extended to interbed multiple prediction at the expense of a huge increase of the computational burden. This cost makes model driven approaches still attractive. Here we propose a methodology based on wavefield extrapolation, that exploits the compact Kirchhoff extrapolation operator that we use to predict water bottom multiples with a single extrapolation step. In the case of interbed multiple the prediction is computed by applying the compact operator twice, the first time from the surface to the upper multiple generator and the second time from the surface to the lower multiple generator. Moreover in the Kirchhoff extrapolation kernel we use asymptotic Green’s functions, and the computation of traveltime is sped up by applying the shifted hyperbola approximation that can provide reasonable accuracy also in the case of VTI media. The effectiveness of the method is demonstrated by the results obtained from the application to both synthetic and field datasets.