Principal aims of seismic data processing are (a) the imaging of the subsurface structure in depth and (b) the determination of physical parameters of the insonified media. (P-/S-wave velocities, densities, litho-stratigraphic parameters, etc.). In the presence of complex structures prestack depth migration is considered the most promising approach for the first task. The second aim, however, requires special emphasis on the conservation of the true amplitude information present in the data. This is needed to obtain accurate values for the desired parameters by amplitude versus offset (AVO), angle dependent reflectivity (ADR), polarity and waveform analysis or other studies.