The contribution of horizontal sea-bed displacements into tsunami generation processes
Résumé
The main reason for the generation of tsunamis is the deformation of the bottom of the ocean caused by an underwater earthquake. Usually, only the vertical bottom motion is taken into accound while the horizontal co-seismic displacements are neglected in the absence of landslides. In the present study we propose a novel methodology for reconstructing all components of the bottom coseismic displacements field. Then, the sea-bed motion is transmitted onto the free surface using a three-dimensional Weakly Nonlinear (WN) approach. We pay a special attention to the evolution of kinetic and potential energies of the resulting wave while the contribution of horizontal displacements into wave energy balance is also quantified. Approaches proposed in this study are illustrated on the July 17, 2006 Java tsunami and some more recent events.
Domaines
Mécanique des fluides [physics.class-ph] Mécanique des fluides [physics.class-ph] Océan, Atmosphère Dynamique des Fluides [physics.flu-dyn] Physique Atmosphérique et Océanique [physics.ao-ph] Physique Numérique [physics.comp-ph] Océanographie Géophysique [physics.geo-ph] Géophysique [physics.geo-ph] Milieux et Changements globauxOrigine | Fichiers produits par l'(les) auteur(s) |
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