Seismic Interferometry from Correlated Noise Sources

It is a well-established principle that cross-correlating seismic observations at different receiver locations can yield estimates of band-limited inter-receiver Green’s functions. This principle, known as function retrieval or interferometry, powerful technique transform noise into signals which enable remote interrogation and imaging the Earth’s subsurface. In practice it often necessary even desirable to rely on already present in environment. Theory underpins many applications ambient interferometry assumes sources are uncorrelated time. However, real-world such trains, highway traffic ocean waves inherently correlated space time, direct contradiction these theoretical foundations. Applying standard interferometric techniques recordings from energy makes liable estimation errors so far have not been fully accounted for theoretically nor practice. We show significant common sources, always perturbing entirely obscuring phase one wishes retrieve. Our analysis explains why stacking may reduce errors, but also shows commonly encountered circumstances will remediate problem. analytical insight allowed us develop novel workflow significantly mitigates effects arising use sources. methodology be used conjunction with existing approaches, improves results both noise. Hence, we expect widely applicable studies.