Pre-stack Deghosting for Variable-depth Streamer Data

Variable-depth streamer acquisition is an acquisition technique aiming at achieving the best possible signal-to-noise ratio at low frequencies by towing the streamer very deeply, but by using a depth profile varying with offset in order not to limit the high frequency bandwidth. Previous papers have shown how a joint deconvolution allows the post-stack deghosting of such variable-depth streamer acquisitions, and the purpose of this paper is to show how this can be generalized to a multichannel joint deconvolution that allows pre-stack though post-imaging deghosting of such acquisitions. After computing migrated gathers as well as mirror migrated gathers, a deghosted gather is computed through joint deconvolution by assuming a parametrical form in offset for the events. This method preserves the AVO behaviour. Synthetic and real data examples are shown.