Residual moveout of 2D multiples in Angle-Domain Common-Image Gathers

Gabriel Alvarez

gabriel@sep.stanford.edu

ABSTRACT

I show that, for specularly-reflected multiples, the constant velocity straight-ray approximation of the residual moveout in Angle-Domain Common-Image Gathers (ADCIGs) is only appropriate for small aperture angles. The approximation is good for the primaries because the difference between the migration velocity and the true velocity is likely to be small. For the multiples, however, this difference may be large and correcting for ray bending produces a better approximation that leads to better focusing of the multiples in the Radon domain. This in turn allows a more accurate muting of the multiples. I show results with two ADCIGs, one synthetic and one real.