HR: 0800h
AN: S11A-1007    [Abstracts]
TI: Paritioned inversion of seismic and geodetic data for high-resolution source inversions
AU: * Thio, H
EM: hong_kie_thio@urscorp.com
AF: URS corp, 566 El Dorado Street, Pasadena, Ca 91101 United States
AB: Due to the availability of earthquake data spanning a very broad range of frequencies and spatial scales (e.g. geodetic, strong-motion, teleseismic data) we now have the potential of obtaining highly detailed views of the earthquake rupture process. The sheer quantity of the data, and the heterogeneity, do pose problems for simultaneous inversion procedures both in terms of scale of the problem as well as how much influence different datasets have over the final result. A simple solution to the problem outlined above, taking advantage of the aforementioned richness in data density and variability, is to divide the inversion procedure into two steps. The first step involves inverting for the slip distribution, which would then be used as a constraint in the second step where we invert for the kinematic parameters. The advantage of this approach is that we now have a-priori knowledge of the slip model before the second inversion that can help reduce the number of free parameters significantly. Practically speaking, we can remove the grid points that have negligible slip, and we can tailor the maximum rise time for every subfault to the total amount of slip on that subfault. It would also be feasible to reduce the length of the timesteps, which gives us an improved resolution of the slip history and allows us to search for a larger range of rupture velocities. Such a method makes more optimal use of the data than a simultaneous inversion. We will present results for some large recent earthquakes to demonstrate the feasibility of this approach, and discuss the applicability of this method to more dynamically oriented inversions.
DE: 7223 Seismic hazard assessment and prediction
DE: 7209 Earthquake dynamics and mechanics
SC: Seismology [S]
MN: 2004 AGU Fall Meeting