A method is described for seismic data processing including receiving a seismic dataset D(s, r; t) representative of a subsurface volume of interest; calculating a pre-migration attenuated travel time t*(s, r; t); performing a first migration on D(s, r; t) to generate common image point (CIP) gathers G(x, h); performing a second migration on D(s, r; t)*t*(s, r; t) to generate weighted common image point (CIP) gathers Gt*(x, h); and calculating a conditioned ratio of the weighted CIP gathers Gt*(x, h) over the CIP gathers G(x, h) to get CIP gathers of attenuated traveltime t*(x, h). The CIP gathers of attenuated traveltime t*(x, h) may be used to perform seismic tomography to generate an attenuation (Q) model.