HR: 11:20h
AN: S21G-05    [PDF]
TI: Importance of Intermediate Principal Stress Magnitude in Dynamic Rupture Propagation in 3D
AU: * Aochi, H
EM: hideo.aochi@irsn.fr
AF: Institut de Radioprotection et de S\^uret\'e Nucl\'eaire, Bureau d'Evaluation des Risques Sismiques pour la S\^uret\'e des Installations Nucl\'eaires, BP17, Fontenay-aux-Roses, 92262 France
AU: Scotti, O
EM: oona.scotti@irsn.fr
AF: Institut de Radioprotection et de S\^uret\'e Nucl\'eaire, Bureau d'Evaluation des Risques Sismiques pour la S\^uret\'e des Installations Nucl\'eaires, BP17, Fontenay-aux-Roses, 92262 France
AU: Berge-Thierry, C
EM: catherine.berge@irsn.fr
AF: Institut de Radioprotection et de S\^uret\'e Nucl\'eaire, Bureau d'Evaluation des Risques Sismiques pour la S\^uret\'e des Installations Nucl\'eaires, BP17, Fontenay-aux-Roses, 92262 France
AB: Dynamic rupture process along non-planar faults has been progressively studied by several groups, but there are few studies that take into account the possibility that slip directions (rake) may change along the different segments. This may actually happen; for example, rupture started on an inverse fault and propagated far along several strike-slip faults during the 2002 Denali, Alaska, earthquake. We apply a 3D boundary integral equation method (BIEM) and numerically study dynamic rupture propagation along a few fault segments subjected to a uniform tectonic regime but with different strikes and dips. Their different geometry implies different rakes for each segment. Furthermore, not only the magnitude but also the direction of the dynamic stress perturbation is calculated since it may not be the same as that of the initial stress regime. Thus, compared to previous models, the occurrence of dynamic rupture jumps depends on the relative segment geometry, the relative value of the dynamic and static friction coefficients, but most importantly, on the relative value of the intermediate principal stresses.
DE: 7209 Earthquake dynamics and mechanics
DE: 7215 Earthquake parameters
DE: 7260 Theory and modeling
SC: Seismology [S]
MN: 2003 Fall Meeting