| Titre | Identifying the rupture plane of the 2001 Nisqually, Washington, earthquake |
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| Auteur | Kao, H ; Wang, K; Chen, R -Y; Wada, I; He, J; Malone, S D |
| Source | Bulletin of the Seismological Society of America vol. 98, no. 3, 2008 p. 1546-1558, https://doi.org/10.1785/0120070160 |
| Image |  |
| Année | 2008 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20070438 |
| Éditeur | Seismological Society of America (SSA) |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1785/0120070160 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Région | Washington; Nisqually |
| Lat/Long OENS | -124.0000 -121.0000 48.0000 46.5000 |
| Sujets | secousses séismiques; études séismiques; mécanismes de tremblement de terre; magnitudes des séismes; risque de tremblement de terre; subduction; zones de subduction; frontières de plaques; marges plaques;
tectonique de plaques; mouvements de la croûte; structure de la croûte; caractéristiques structurales; failles; sismicité; interpretations sismiques; sismographes; séismologie; regimes thermiques; Plaque de Juan de Fuca; Tremblement de terre de
Nisqually ; géophysique; tectonique |
| Illustrations | cartes de localisation; sismogrammes; profils |
| Diffusé | 2008 06 01 |
| Résumé | (disponible en anglais seulement)
The 2001 Nisqually earthquake occurred within the subducting Juan de Fuca plate. Previous seismic and geodetic studies could not confidently identify its actual
fault plane from the two nodal planes. In this study, we apply the recently developed Source-Scanning Algorithm to local seismic waveforms and show unambiguously that the steeply east-dipping plane is the rupture plane. The rupture began near the
bottom of the subducting crust and propagated downward into the subducting uppermost mantle. If intraslab earthquakes are assumed to be due to dehydration embrittlement, the source dimension is unlikely to grow any larger because the warm thermal
state of the subducting Juan de Fuca plate limits dehydration to a shallow depth below the slab surface. Numerical modelling of thermal structures indicates that dehydration embrittlement can only take place in the top 10 km of the subducting mantle,
implying that the maximum size of an intraslab earthquake in northern Cascadia should be Mw~7 or less. |
| GEOSCAN ID | 224540 |
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