HR: 1330h
AN: S42E-0215    [PDF]
TI: Rupture process of the Mw=6.9 Boumerdes (Algeria) earthquake of May 21, 2003 from seismological data
AU: * Vallee, M
EM: vallee@dase.bruyeres.cea.fr
AF: Laboratoire de D\'{e}tection G\'{e}ophysique (LDG-CEA), B\^{a}timent Sables, BP 12, Bruyeres-Le-Chatel, 91680 France
AU: Delouis, B
EM: delouis@geoazur.unice.fr
AF: G\'{e}osciences Azur (CNRS/UNSA/IRD), 250, rue A. Einstein, Valbonne, 06560 France
AU: Deschamps, A
EM: deschamps@geoazur.unice.fr
AF: G\'{e}osciences Azur (CNRS/UNSA/IRD), 250, rue A. Einstein, Valbonne, 06560 France
AU: Deverchere, J
EM: jacdev@univ-brest.fr
AF: Universit\'{e} de Bretagne Occidentale, IUEM, Technop\^{o}le Brest-Iroise, Place Nicolas Copernic, Plouzan\'{e}, 29280 France
AU: Yelles, K
EM: email: kyelles@yahoo.fr
AF: C.R.A.A.G., BP 63, route de l'Observatoire, Bouzareah, Alger, 16340 Algeria
AU: Hello, Y
EM: hello@obs-vlfr.fr
AF: G\'{e}osciences Azur (CNRS/UNSA/IRD), 250, rue A. Einstein, Valbonne, 06560 France
AU: Calais, E
EM: ecalais@purdue.edu
AF: Purdue University, Dept. of Earth & Atmospheric Sciences, West Lafayette, IN 47907-1397 United States
AB: The understanding of the destructive earthquake that struck northern Algeria on May 21, 2003 is complicated by the fact that it most likely ruptured the earth surface offshore. Notwithstanding, a number of observations, measurements, and recordings can be used to constrain the main aspects of the rupture process of the event. We use seismological data, specifically teleseismic body and surface waves, to determine how slip was distributed in space and time relative to the mainshock hypocenter. Our preliminary results indicate that the essential part of the reverse faulting rupture occurred at shallow depth ($<$ 10 km) on a south dipping fault plane and was associated with a strong directivity effect toward the SW. We intend to improve the determination of the hypocenter itself by carrying out a relative location with respect to the aftershocks which were recorded by OBS deployed in the epicentral area a few days after the mainshock. Onland ground deformation, such as coastal uplift, as well as offshore imaging of the activated fault (MARADJA cruise) are also used to constrain further the spatial properties of the rupture, in particular its absolute location and geometry.
DE: 1242 Seismic deformations (7205)
DE: 7209 Earthquake dynamics and mechanics
DE: 7215 Earthquake parameters
DE: 7260 Theory and modeling
SC: Seismology [S]
MN: 2003 Fall Meeting