Spatiotemporal Variations of Ground Motion in Northern Chile before and after the 2014 M-w 8.1 Iquique Megathrust Event
- To evaluate the spatiotemporal variations of ground motions in northern Chile, we built a high-quality rock seismic acceleration database and an interface earthquakes catalog. Two ground-motion prediction equation (GMPE) models for subduction zones have been tested and validated for the area. They were then used as backbone models to describe the time-space variations of earthquake frequency content (Fourier and response spectra). Consistent with previous studies of large subduction earthquakes, moderate interface earthquakes in northern Chile show an increase of the high-frequency energy released with depth. A regional variability of earthquake frequency content is also observed, which may be related to a lateral segmentation of the mechanical properties of the subduction interface. Finally, interface earthquakes show a temporal evolution of their frequency content in the earthquake sequence associated with the 2014 Iquique M-w 8.1 megathrust earthquake. Surprisingly, the change does not occur with the mainshock but is associatedTo evaluate the spatiotemporal variations of ground motions in northern Chile, we built a high-quality rock seismic acceleration database and an interface earthquakes catalog. Two ground-motion prediction equation (GMPE) models for subduction zones have been tested and validated for the area. They were then used as backbone models to describe the time-space variations of earthquake frequency content (Fourier and response spectra). Consistent with previous studies of large subduction earthquakes, moderate interface earthquakes in northern Chile show an increase of the high-frequency energy released with depth. A regional variability of earthquake frequency content is also observed, which may be related to a lateral segmentation of the mechanical properties of the subduction interface. Finally, interface earthquakes show a temporal evolution of their frequency content in the earthquake sequence associated with the 2014 Iquique M-w 8.1 megathrust earthquake. Surprisingly, the change does not occur with the mainshock but is associated with an 8 month slow slip preceding the megathrust. Electronic Supplement: Strong-motion database.…
Verfasserangaben: | Jesus Pina-Valdes, Anne SocquetORCiD, Fabrice CottonORCiDGND, Sebastian SpechtORCiD |
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DOI: | https://doi.org/10.1785/0120170052 |
ISSN: | 0037-1106 |
ISSN: | 1943-3573 |
Titel des übergeordneten Werks (Englisch): | Bulletin of the Seismological Society of America |
Verlag: | Seismological Society of America |
Verlagsort: | Albany |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Datum der Erstveröffentlichung: | 27.02.2018 |
Erscheinungsjahr: | 2018 |
Datum der Freischaltung: | 17.12.2021 |
Band: | 108 |
Ausgabe: | 2 |
Seitenanzahl: | 14 |
Erste Seite: | 801 |
Letzte Seite: | 814 |
Fördernde Institution: | Chilean National Commission of Science and Technology (CONICYT) |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
Peer Review: | Referiert |