Summary

The converted-wave common-azimuth downward-continuation operator (PS-CAM) and the single-mode common-azimuth operator share the advantage that they only need a prestack cube of data with four dimensions ($t, {\rm CMP}_X, {\rm CMP}_Y,H_X$), instead of the entire five dimensions ($t, {\rm CMP}_X, {\rm CMP}_Y,H_X,H_Y$). The five dimensions are reduced to four dimensions through the process described in Chapter 4. I first present the PS common-azimuth downward-continuation operator. Then, I use this PS-CAM operator to obtain two images for the PS section from the 3-D OBS dataset from the Alba oil field. The two images corresponds to the following processes: 1. The common-azimuth migration of the data regularized using Normal Moveout. 2. The common-azimuth migration of the data regularized using PS-AMO. Both of these common-azimuth cubes correspond to the conventional method result and the weighted adjoint result from Chapter 4, respectively. The final results show that the image using the result of the weighted adjoint solution, which incorporates the PS-AMO operator, is significantly better than the image using the result of the conventional method.