Shot-profile migration of GPR data

Multi-offset GPR data possess a number of important advantages over constant-offset data, and are becoming increasingly popular within the GPR community. With the availability of these data comes the opportunity to experiment with state-of-the-art seismic imaging techniques. Here, we consider the application of shot-profile migration, a prestack scalar wave-equation imaging method, to 2-D multi-offset GPR data. With this method, source and receiver wavefields of individual shot records are propagated separately and combined at depth with application of an imaging condition. Receiver wavefields are comprised of recorded traces, and source wavefields are modeled from point sources at the transmitter locations. The complete migrated image is the sum of all overlapping shot-record migrations. After a brief discussion on the limiting assumptions of applying this scalar wave-equation approach to GPR data, we outline the theory of shot-profile migration. We then demonstrate the application of the method to multi-offset GPR data collected near Langley, British Columbia, Canada.