The theory of coda wave interferometry
نویسنده
چکیده
Coda waves are sensitive to changes in the subsurface because the strong scattering that generates these waves causes coda waves to repeatedly sample a limited region of space. Coda wave interferometry is a technique that exploits this sensitivity to estimate weak changes in the medium from a comparison of the coda waves before and after the perturbation. Here I present the general theory of coda wave interferometry, and show how the time-shifted correlation coefficient can be used to estimate the mean and variance of the travel time perturbation caused by the perturbation of the medium. This mean and average are defined based on the intensity of the coda waves. I show how this general theory can be used to estimate changes in the wave velocity, in the location of scatterer positions, and in the source location.
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