Reverse-time migration imaging with/without multiples

Zaiming Jiang, John C. Bancroft, Laurence R. Lines

One of the challenges with reverse-time migration based on finite-difference method is the problems of computational costs, in terms of free disk space and/or computational time. This report discusses the principle of a new imaging condition, referred as `first arrival imaging condition', and shows the advantage of less computational costs of this method, compared to the widely used source-normalized crosscorrelation imaging condition for reverse-time migration. Principally, with crosscorrelation imaging conditions, all the multiples inside both forward modelling and reverse-time migration wavefields are involved; on the other hand, with the first arrival imaging condition, the multiples in the wavefields are not included.