Non-linear iterative inversions for the distribution of noise sources
Abstract
For a given set of observed noise cross correlations, we model their sources as temporally stochastic and spatially fixed on the surface of Earth. The expectation values of seismic correlations between station pairs are then formally interpreted in terms of Green's functions of the medium and the distribution of wave sources. To simplify the analysis, we use 1-D Green's functions (PREM) excited over the surface of the Earth. We present inversions of noise-correlation amplitudes around southern California, Europe and Ecuador. Because the problem is computationally cheap, we can perform Gauss-Newton inversions and capture model and data uncertainties. We also present theoretical evidence to support the use of one-bit correlations over raw measurements.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.S53C2513H
- Keywords:
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- 7255 SEISMOLOGY / Surface waves and free oscillations