Seismic interferometry—turning noise into signal

TLDR

Seismic interferometry turns normally discarded noise and scattered waveforms into useful data by exploiting their reflection and refraction through subsurface heterogeneities. The study aims to unravel subsurface information from complex waveforms by leveraging seismic interferometry. It explains how seismic interferometry works and illustrates its application with several examples. The authors find that the solution to extracting subsurface information is surprisingly simple.

Abstract

Turning noise into useful data—every geophysicist's dream? And now it seems possible. The field of seismic interferometry has at its foundation a shift in the way we think about the parts of the signal that are currently filtered out of most analyses—complicated seismic codas (the multiply scattered parts of seismic waveforms) and background noise (whatever is recorded when no identifiable active source is emitting, and which is superimposed on all recorded data). Those parts of seismograms consist of waves that reflect and refract around exactly the same subsurface heterogeneities as waves excited by active sources. The key to the rapid emergence of this field of research is our new understanding of how to unravel that subsurface information from these relatively complex-looking waveforms. And the answer turned out to be rather simple. This article explains the operation of seismic interferometry and provides a few examples of its application.