CONCLUSION

We have presented an improved method to compute ADCIGs from ODCIGs. Our implementation demonstrates the importance of using a 3-D transformation. We have first considered a common-azimuth case in which the rays are coplanar and the source receiver orientation is parallele to the in-line direction. We have then presented the full prestack migration case in which we have imposed the rays to be coplanar at the imaging point. Non-zero azimuth reflections have also been taken into account. Our next step is to consider the more general case of non-coplanar rays at the imaging point. This situation occurs when the migration velocity is not correct.