Diffraction analysis by tangent-phase interferometry

Tangent-phase interferometry approach makes it possible to reconstruct seismic signals when the conventional stationarity conditions are not satisfied because of insufficient illumination by real sources around receivers. The virtual method is based on tangent-phase correction for the wavefield crosscorrelations in a modified representation integral, and provides results for selected events. In this work we investigate the representation for diffraction signals and for direct events, with applications in the crosswell geometry. The results show that it is possible to reconstruct local diffraction patterns from buried objects, thus obtaining improved information about their dimensions and imaging, also in the case of insufficient illumination coverage for the signal representation by conventional seismic interferometry.