Separated Wavefield Imaging of Ocean Bottom Seismic (OBS) Data

We discuss a depth imaging solution that uses primaries and all orders of multiple reflections to image seismic data from seabed acquisitions. The processing sequence starts by separating the up-going (P-UP) and down-going (P-DWN) wavefields from the seabed hydrophone and geophone measurements. The data are then organized into receiver gathers and the P-UP and P-DWN wavefields are migrated independently. By using the primaries and all orders of multiples in the migration, we greatly improve the resolution of the image and significantly expand the areal illumination of the survey. The improvements are not limited to the stack image; our imaging solution produces finely sampled angle gathers that could be further utilized for velocity model building or image enhancement post migration. We present a successful application of the technology to an Ocean Bottom Cable (OBC) recording system deployed for the Petrobras Permanent Reservoir Monitoring (PRM) pilot over the Jubarte field in the Campos basin offshore Brazil.