Articles | Volume 12, issue 11
https://doi.org/10.5194/se-12-2523-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-12-2523-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Very early identification of a bimodal frictional behavior during the post-seismic phase of the 2015 Mw 8.3 Illapel, Chile, earthquake
Cedric Twardzik
CORRESPONDING AUTHOR
Université Côte d'Azur, CNRS, Observatoire de la Côte d'Azur, IRD, Geoazur, UMR 7329, Valbonne, France
now at: Institut de Physique du Globe de Strasbourg, UMR 7516, Université de Strasbourg, EOST, CNRS, Strasbourg, France
Mathilde Vergnolle
Université Côte d'Azur, CNRS, Observatoire de la Côte d'Azur, IRD, Geoazur, UMR 7329, Valbonne, France
Anthony Sladen
Université Côte d'Azur, CNRS, Observatoire de la Côte d'Azur, IRD, Geoazur, UMR 7329, Valbonne, France
Louisa L. H. Tsang
Université Côte d'Azur, CNRS, Observatoire de la Côte d'Azur, IRD, Geoazur, UMR 7329, Valbonne, France
now at: University of Surrey, International Study Centre, Guildford, United Kingdom
Related authors
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Itzhak Lior, Anthony Sladen, Diego Mercerat, Jean-Paul Ampuero, Diane Rivet, and Serge Sambolian
Solid Earth, 12, 1421–1442, https://doi.org/10.5194/se-12-1421-2021, https://doi.org/10.5194/se-12-1421-2021, 2021
Short summary
Short summary
The increasing use of distributed acoustic sensing (DAS) inhibits the transformation of optical fibers into dense arrays of seismo-acoustic sensors. Here, DAS strain records are converted to ground motions using the waves' apparent velocity. An algorithm for velocity determination is presented, accounting for velocity variations between different seismic waves. The conversion allows for robust determination of fundamental source parameters, earthquake magnitude and stress drop.
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Short summary
After an earthquake, the fault continues to slip for days to months. Yet, little is know about the very early part of this phase (i.e., minutes to hours). We have looked at what happens just after an earthquake in Chile from 2015. We find that the fault responds in two ways: south of the rupture zone it slips seismically in the form of aftershocks, while north of the rupture zone it slips slowly. Early inference of such bimodal behavior could prove to be useful for forecasting aftershocks.
After an earthquake, the fault continues to slip for days to months. Yet, little is know about...