Sampling and Illumination Aspects of Seismic Interferometry in Horizontally Layered Media

Seismic Green's function retrieval or seismic interferometry (SI) refers to the principle of generating new seismic responses by crosscorrelating seismic observations at different receiver locations. We consider retrieving a reflection response between receivers at an (approximately) horizontally layered medium. Only transmission responses due to sources that are, in a Fresnel sense, inline with the receivers are needed as an input for the SI relation. The sampling criterion for the sources is much more relaxed than Nyquist. Sources at the edges of the source distribution will cause distortion of the retrieved reflections or even spurious events. Based on a tau-p transform of the transmission responses, a filter can be designed to remove kinematically wrong events from the retrieved results.