3D joint full wavefield migration of surface and VSP data

Abstract

Surface seismic data has as main advantage that it can provide an image over an extended area. However, due to the involved two-way travel paths – including twice propagating through a possibly unconsolidated near-surface area for land data – the resolution usually is quite limited. Borehole-related seismic data, like walk-way, walk-around or 3D VSP data, has a broader frequency band and better data quality, which results in a higher resolution and more detailed image. The main disadvantage of multi-shot VSP data is the non-uniform distribution of the fold, which rapidly decreases while moving away from the well. This makes the areal extend of the final image very limited. In practice, VSP and surface seismic data are processed separately and the VSP image is spliced into the surface seismic data image. This workflow does not guarantee a perfect tie of the two images.