Citation

Larmat C, Guyer RA, Johnson PA, Montagner JP. J. Acoust. Soc. Am. 2013; 134(5): 4034.

Affiliation

EES-17, Los Alamos National Lab., P.O. Box 1663, M.S. D452, Los Alamos, NM 87545carene@lanl.gov.

Copyright

(Copyright © 2013, American Institute of Physics)

DOI

10.1121/1.4830730

PMID

24181136

Abstract

Wave physics is one domain where reversing time is possible and has led to interesting applications. In acoustics, Parvulescu and Clay (1965) used what they termed a "matched signal technique" to beat multi-reverberation in the shallow sea. In seismology, McMechan (1982) demonstrated the feasibility of what he termed "wavefield extrapolation" to locate seismic sources. Since then, other concepts and applications, all related to time-reversal, have often been proved to be successful where other techniques have failed. This success is due to the inherent ability of time-reversal to function well in complex propagation media as well as the remarkable robustness of the method with sparse receiver coverage. The key aspect of time-reversal for future applications in seismology is that it relies on no a priori assumption about the source. This allows automatic location of earthquakes and the study of seismic events for which the assumption of point source breaks down. This is the case of big earthquakes (Mw >8) for which the rupture length and source duration extend to hundreds of kilometers and several tens of seconds. We will show an application to the 2011 Japan earthquake, to icequakes related to glaciers motions in Greenland and to seismic tremor with no clear onset.

Language: en