US Patent 10324204 Diffraction imaging systems and methods using specularity gathers

In some embodiments, a seismic processing method comprises assembling a specularity gather by determining a specularity value at each of a plurality of subsurface locations, and summing trace amplitudes into a plurality of bins, each bin characterized by a range of specularity values. The specularity value at a subsurface location is computed according to an angle between a normal to a local reflector and a direction of a total (source+receiver) traveltime gradient. For example, the specularity may be proportional to (e.g. equal to) a magnitude of the cosine of the angle. A diffraction image may be generated by summing specularity gather data over specularity, with specular event amplitudes attenuated relative to diffractive event amplitudes.