Biondi and Tisserant (2003) have presented a method for computing 3D ADCIGs from full 3D pre-stack migration.
Attenuation of these multiples from 3D ADCIGs can be fully accomplished with the methodology presented in this paper.
In this way, the two dimensional space data of ADCIGs, d(z,[gamma]), is transformed into a three-dimensional space model, m(z,q,h).
In an ideal case, primaries would be perfectly horizontal in the ADCIGs and would thus map in the space model to the zero-curvature (q = 0) plane (e.
Figure 5 shows a close-up comparison of the primaries extracted with the standard 2D transform (Sava and Guitton, 2003) and with the apex-shifted Radon transform for the two ADCIGs at the top in Figure 5.
In order to assess the effect of better attenuation of the diffracted multiples on the angle stack of the ADCIGs, a total of 310 ADCIGs corresponding to horizontal positions 3000 m to 11000 m were processed (Figure 8).
An alternative could be doing a standard Radon demultiple before prestack migration to facilitate the choice of the migration velocities, and 3D Radon demultiple on the ADCIGs to attenuate residual multiples, in particular diffracted multiples.