HR: 1340h
AN: S13B-0202 [Abstracts]
TI: Rupture Pomess of Four Medium Size Earthquakes That Occurred in the Gulf of California
AU: Rodriguez-Lozoya, H E
EM: lozoya@cicese.mx
AF: Centro de Investigacion Cientifica y de Educacion
Superior de Ensenada (CICESE), km 107 Carretera Tijuana-Ensenada, Ensenada, BC 22860
Mexico
AU: * Rebollar, C J
EM: rebollar@cicese.mx
AF: Centro de Investigacion Cientifica y de Educacion
Superior de Ensenada (CICESE), km 107 Carretera Tijuana-Ensenada, Ensenada, BC 22860
Mexico
AU: Quintanar, L
EM: luisq@ollin.igeofcu.unam.mx
AF: Instituto de Geofisica, Universidad Autonoma de
México (UNAM), Ciudad Universitaria, Mexico D. F., 041510
Mexico
AB:
Four earthquakes with magnitudes of 5.3, 5.6, 6.1 and 6.2 located in the Gulf of California Extensional Province were studied
to obtain their rupture process. A network of broadband seismic stations located around the Gulf of California recorded the
events (NARS-Baja and RESBAN). Body waveform modeling and the inversion of the seismic moment tensor were used to obtain the
fault geometry. From forward body waveform modeling and from the time-domain moment tensor inversion we obtained source
depths in the range from 4 to 6 km. We used Yagi et al. (1999) inversion code to invert near-source broadband and
strong-ground-motion waveforms to get the spatial slip distribution over the fault. We found that the source rupture process
of the magnitude 5.3 and 5,6 have simple moment-rate functions and source time duration of 10 and 17 seconds respectively.
Magnitude 5.3 event was a normal event and magnitude 5.6 was a right lateral strike-slip event. Magnitude 6.1 and 6.3 were
right lateral strike-slip events with a complex rupture process with three sources of seismic moment release. Time duration
of these events were 30 and 35 seconds respectively. Time duration of the moment-rate functions are large compared with
similar magnitude events calculated elsewhere, we think that this is because we are inverting a large window of the
seismogram that contain energy that it is not seen at regional distances or teleseismic distances.
UR: http://www.cicese.mx
DE: 7215 Earthquake source observations (1240)
SC: Seismology [S]
MN: Fall Meeting 2005