Redshift of earthquakes via focused blind deconvolution of teleseisms
Name
bharadwaj-etal_preprint_redshift_focused_blind_decon_v2.pdf
Description
Submitted version
Size
3.45 MB
Format
Adobe PDF
Checksum (MD5)
3daff5322371412a096175a12bbb7d6e
Author(s)
Bharadwaj, Pawan
Meng, Chunfang
Fournier, Aimé
Demanet, Laurent
Fehler, Mike
Date Issued
2020
Journal
Geophysical Journal International
Publisher
Oxford University Press (OUP)
Version
Original manuscript
Abstract
© 2020 The Author(s) 2020. Published by Oxford University Press on behalf of The Royal Astronomical Society. We present a robust factorization of the teleseismic waveforms resulting from an earthquake source into signals that originate from the source and signals that characterize the path effects. The extracted source signals represent the earthquake spectrum, and its variation with azimuth. Unlike most prior work on source extraction, our method is data-driven, and it does not depend on any path-related assumptions, for example, the empirical Green's function. Instead, our formulation involves focused blind deconvolution (FBD), which associates the source characteristics with the similarity among a multitude of recorded signals. We also introduce a new spectral attribute, to be called redshift, which is based on the Fraunhofer approximation. Redshift describes source-spectrum variation, where a decrease in high-frequency content occurs at the receiver in the direction opposite to unilateral rupture propagation. Using the redshift, we identified unilateral ruptures during two recent strike-slip earthquakes. The FBD analysis of an earthquake, which originated in the eastern California shear zone, is consistent with observations from local seismological or geodetic instrumentation.
MIT Department
Massachusetts Institute of Technology. Department of Mathematics
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1093/GJI/GGAA419
