The silent earthquake of 2002 in the Guerrero seismic gap, Mexico (Mw=7.6): Inversion of slip on the plate interface and some implications
Por:
Iglesias A., Singh S.K., Lowry A.R., Santoyo M., Kostoglodov V., Larson K.M., Franco-Sánchez S.I.
Publicada:
1 ene 2004
Resumen:
We invert GPS position data to map the slip on the plate interface during an aseismic, slow-slip event, which occurred in 2002 in the Guerrero seismic gap of the Mexican subduction zone, lasted for ?4 months, and was detected by 7 continuous GPS receivers located over an area of ?550×250 km2. Our best model, under physically reasonable constraints, shows that the slow slip occurred on the transition zone at a distance range of 100 to 170 km from the trench. The average slip was about 22.5 cm (Mo?2.97 ×1027 dyne-cm, Mw=7.6). This model implies an increased shear stress at the bottom of the locked, seismogenic part of the interface which lies updip from the transition zone, and, hence. an enhanced seismic hazard. The results from other similar subduction zones also favor this model. However, we cannot rule out an alternative model that requires slow slip to invade the seismogenic zone as well. A definitive answer to this critical issue would require more GPS stations and long-term monitoring.
Filiaciones:
Iglesias A.:
Instituto de Geofísica, Univ. Nac. Autonoma de México, México, DF, Mexico
Singh S.K.:
Instituto de Geofísica, Univ. Nac. Autonoma de México, México, DF, Mexico
Lowry A.R.:
Department of Physics, University of Colorado, Boulder, CO, United States
Santoyo M.:
Instituto de Geofísica, Univ. Nac. Autonoma de México, México, DF, Mexico
Kostoglodov V.:
Instituto de Geofísica, Univ. Nac. Autonoma de México, México, DF, Mexico
Larson K.M.:
Dept. of Aerospace Engineering Sci., University of Colorado, Boulder, CO, United States
Franco-Sánchez S.I.:
Instituto de Geofísica, Univ. Nac. Autonoma de México, México, DF, Mexico
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