HR: 0800h
AN: S21B-0557    [Abstracts]
TI: Analysis of Different Frictional Laws and Their Implications in the Scaling and Mode of Earthquake Rupture Using a Dynamic Elasto-plastic Frictional Contact Model and the Finite Element Method.
AU: * Olsen-Kettle, L M
EM: lkettle@esscc.uq.edu.au
AF: Earth Systems Science Computational Centre, Sir James Foots Building (47a) The University of Queensland, St Lucia, Qld 4072, Australia
AU: Weatherley, D K
EM: uqdweath@uq.edu.au
AF: Earth Systems Science Computational Centre, Sir James Foots Building (47a) The University of Queensland, St Lucia, Qld 4072, Australia
AU: Gross, L
EM: l.gross@uq.edu.au
AF: Earth Systems Science Computational Centre, Sir James Foots Building (47a) The University of Queensland, St Lucia, Qld 4072, Australia
AU: Muhlhaus, H
EM: muhlhaus@esscc.uq.edu.au
AF: Earth Systems Science Computational Centre, Sir James Foots Building (47a) The University of Queensland, St Lucia, Qld 4072, Australia
AU: Xing, H
EM: xing@esscc.uq.edu.au
AF: Earth Systems Science Computational Centre, Sir James Foots Building (47a) The University of Queensland, St Lucia, Qld 4072, Australia
AB: Dynamic simulations of rupture propagation in crustal fault systems are presented. We demonstrate the applicability of our elasto-plastic fault model for modeling dynamic rupture and wave propagation in fault systems. Firstly, we demonstrate the rich array of dynamic properties produced by our elasto-plastic finite element fault model. These are governed by a number of model parameters including: the spatial and material heterogeneity of the fault, the loading strains applied, and not least of all the frictional law employed. Rupture propagation on a fault is controlled by the constitutive properties of the fault. A dynamic elasto-plastic constitutive law for the interface friction at the fault is formulated based on the Coulomb failure criterion and applied in a way analogous to non-associated elasto-plasticity. The penalty method is used to enforce the fault boundary conditions. We employ various slip weakening frictional laws to examine their effect on the resulting earthquake rupture speed, size and mode. We also provide benchmark tests of our method against other reported solutions in the literature. Secondly, we present simulations of multiple earthquake cycles. We propose a numerical method that can produce synthetic earthquake catalogues, which implements four distinct phases sequentially: loading of the next earthquake event, dynamic rupture of the fault, an absorbing wave phase, and a sub-cycle of any (dynamically determined) number of creep events between earthquakes.
DE: 0560 Numerical solutions (4255)
DE: 3285 Wave propagation (0689, 2487, 4275, 4455, 6934)
DE: 5120 Plasticity, diffusion, and creep
DE: 7209 Earthquake dynamics (1242)
DE: 8118 Dynamics and mechanics of faulting (8004)
SC: Seismology [S]
MN: 2007 Fall Meeting