Fiche du document
15 janvier 2016
- doi: 10.4000/books.psorbonne.3799
- isbn: 9782859446437
- eisbn: 9782859448233
https://www.openedition.org/12554 , info:eu-repo/semantics/openAccess
Mots-clés
Sumatra tsunami modélisation hydrodynamique différences finies Banda Aceh Tsunami prévention environnement aspect environnemental aspect social Humanities, Multidisciplinary SOC026000 JHBSujets proches
Instruction and study--Methods Seabed Sea bed Seafloor Bottom of the ocean Sea floor Floor of the ocean Ocean floor Subsoil of the ocean floor Molding (Clay, plaster, etc.) Clay modeling Modelling Heights Elevations Instruction and study--MethodsCiter ce document
Hélène Hébert et al., « Modélisation numérique du tsunami dans les districts de Banda Aceh et Lhok Nga », Publications de la Sorbonne, ID : 10.4000/books.psorbonne.3799
Métriques
Partage / Export
Résumé
The 2004 tsunami in the Indian Ocean has given the opportunity to gather an unprecedented database of observations, which allows discussing the numerical methods of tsunami modeling. Most of these methods solve the hydrodynamical equations under the “shallow water assumption”, considering that the tsunami wavelengths are much longer than the water depth. Numerical schemes using finite differences are applied, with an initiation equal to the coseismic seafloor deformation, which can be computed thanks to seismological studies. Bathymetric and topographic data acquired in the framework of Tsunarisque have allowed to build a digital bathymetry and topography model describing the devastated area in Banda Aceh and Lhok Nga, and necessary for the modeling.In this study, the seismological source is taken from the inversion of tsunami waveforms recorded by altimetry satellites two hours after the mainshock. Using the corresponding initial seafloor deformation, tsunami waves are modelled in the area of Banda Aceh. On average the modelling results indicate a horizontal penetration reaching 5 to 6 km, and runup heights not exceeding 8 m, except in Lhok Nga where the computed amplitudes reach 14 m. The modelled wave heights fit rather well the observations. However in the area of Lhok Nga, the modelled amplitudes are well below the observed extreme amplitudes. The results underline that this preliminary study also allows to further consider other seismological parameters to describe the source of the 2004 mega-tsunami.