This chapter presents the azimuth moveout for converted waves, PS-AMO, that is the sequential application of converted-wave dip moveout and its inverse. PS-AMO preserves the resolution of dipping events and internally applies a correction for the lateral shift between the common midpoint and the common reflection/conversion point. This chapter also presents the implementation of PS-AMO in the log-stretch frequency-wavenumber domain.
Chapter 4 also formulates the irregular acquisition geometry problems in the least-squares problem. This method collapses the crossline offset dimension to form a 4-dimensional cube to be used for migration using the common-azimuth downward-continuation operator future processing techniques, such as common-azimuth migration. This method uses the information of surrounding traces, through the PS-AMO operator, to fill in the acquisition gaps, and form a regularized 4-dimensional cube. The solutions for the least-squares problem are illustrated using the real 3-D OBS dataset from the Alba oil field in the North Sea.