HR: 13:55h
AN: S33C-02    [Abstracts]
TI: Spontaneous Rupture Modeling of the 2004 Parkfield Earthquake With Estimates of the Fracture and Radiated Energy
AU: * Ma, S
EM: sma@crustal.ucsb.edu
AF: Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA 93106 United States
AU: Custodio, S
EM: susana@crustal.ucsb.edu
AF: Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA 93106 United States
AU: Liu, P
EM: pcliu@crustal.ucsb.edu
AF: Inistitute for Crustal Studies Inistitute for Crustal Studies, University of California, Santa Barbara, Santa Barbrara, CA 93106 United States
AU: Archuleta, R
EM: ralph@crustal.ucsb.edu
AF: Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA 93106 United States
AU: Archuleta, R
EM: ralph@crustal.ucsb.edu
AF: Inistitute for Crustal Studies Inistitute for Crustal Studies, University of California, Santa Barbara, Santa Barbrara, CA 93106 United States
AB: The 2004 Parkfield MW6 earthquake offers an unprecedented set of near-field ground motions that can be used to constrain the details of the rupture process of the source. We estimate both the fracture energy and radiated energy from a spontaneous, dynamic rupture model for the Parkfield earthquake. To approximate a large contrast in the material velocities across the fault, we use different 1-D velocity models for the northeast and southwest sides of the fault. The stress drop spatial distribution on the fault is calculated from a kinematic slip distribution (Cust"rdio et al., 2005). From this distribution of stress drop, we produce an initial stress distribution on the fault. The constitutive law for friction is linear slip-weakening with a constant slip weakening distance. By trial-and-error we modify both the initial stress and yield stress until the synthetics match the near-source ground motions. The resulting dynamic rupture model is used to make a robust estimate of the radiated energy and the fracture energy during the Parkfield earthquake.
DE: 7209 Earthquake dynamics (1242)
DE: 7212 Earthquake ground motions and engineering seismology
DE: 7215 Earthquake source observations (1240)
DE: 7290 Computational seismology
SC: Seismology [S]
MN: Fall Meeting 2005