1 / 10

Responsable: Martin Mai, ETH Zürich

S eismic wave P ropagation and I maging in C omplex media: a E uropean network Local scale group. Responsable: Martin Mai, ETH Zürich. Speaker: Raoul Madariaga Senior researcher Ecole Normale Supérieure Paris. Earthquake seismology. Fault model. Direct. Inverse. Modelling. Dynamics.

jesus
Télécharger la présentation

Responsable: Martin Mai, ETH Zürich

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Seismic wave Propagation and Imaging in Complex media: a European networkLocal scale group Responsable: Martin Mai, ETH Zürich Speaker: Raoul Madariaga Senior researcher Ecole Normale Supérieure Paris

  2. Earthquake seismology Fault model Direct Inverse Modelling Dynamics Rupture propagation model Propagation Kinematics Wave propagation model

  3. Different scales in earthquake dynamics . BB Seismic waves Macroscale (< 0.3 Hz l> 5 km) Hifi Seismic waves Mesoscale (>0.5 Hz l<2 km) Steady state mechanics Microscale vr (non-radiative) (l~ 100 m) This hierarchy of problems was proposed by Kostrov’s

  4. Challenges in macroscale Kinematics : Are inversions realistic? -> Don’t ask! Are they stable? -> Blind Test Dynamics : How do we set up kinematic inversions that are compatible with dynamics ? Both : How to extend the inversions beyond 0.3 Hz, so that they are useful in engineering ? How to interface with GPS, interferometry and geology?

  5. Earthquakes as dynamic shear ruptures Preexisting Fault system in the Mojave desert Epicenter Rupture modelled on the complex fault system determined from Geology, Geodesy and Seismology

  6. Kinematic vs dynamic modelling Wald and Heaton 1994 Peyrat Olsen Madariaga 2001 Landers 28 June 1992

  7. Model B Model E The « smooth » fault model develops supershear shocks Why? Detailed energy balance Two attempts to model the Izmit Earthquake The « rough » fault models produces subshear ruptures Aochi, Fuyama, Madariaga, 2003 Super shear shock

  8. A simple shear crack (earthquake) moving at fast speed vr Local energy balance friction Es = DU - Gc ini Gc DU slip Dc

  9. Mesoscale: Compare a complex fault to a flat one S waves Residual stresses Rupture front Velocity z Stress zx Stresszy Madariaga and Ampuero, AGU 05 Slow rupture

  10. Outlook for Next 2 years • Kinematics: Improvement of wave propagation, • methodology and structure • (Bonnefoy, Oprsal, Tapia) • Kinematics inversion: Compare linear and non- linear techniques. (Holden, Festa) • Dynamic inversion: Do it! Let it become the norm rather • than the exception. (DiCarli, Burjanek) • Mesocale : Understand the generation of high • frequencies and EQ energy balance • Microscale: See Pablo Ampuero’s presentation Earthquake seismology progresses as earthquake recordingand data availability improves

More Related