Seismic Interferometry Using a Generalized-phase Approach

In this work we investigate the use of seismic interferometry based on a generalized-phase concept using natural and model-based information. We present a generalized-phase interferometry method based on tangent analysis, which corrects the correlation data before summation. The approach makes it possible to synthesize virtual signals usually vanishing in the conventional seismic interferometry summation. New traces are obtained at new stationary projected points for different source positions along the signal wavefronts passing through the real reference receiver. The position of the projected points is estimated by minimization of traveltimes using wavefront constraint and tangent information. The method, using a mixed processing, partially based on velocity-model knowledge and partially on interferometry, can be used for selected events, including reflections with different stationary conditions and projection points, to extend the interferometry to seismic exploration data where conventional illumination coverage is not sufficient to obtain stationary-phase condition.