HR: 16:50h
AN: S34A-03    [Abstracts]
TI: Adding seismic broadband analysis to characterize Andean backarc seismicity in Argentina
AU: * Alvarado, P
AF: Conicet-Univ. Nac. de San Juan, Meglioli 1160 S, San Juan, 5400, Argentina
AU: Giuliano, A
AF: INPRES, Roger Balet 47 N, San Juan, 5400, Argentina
AU: Beck, S
AF: Univ. of Arizona, Gould Simpson Bldg. 1040 E, Tucson, AZ 85721, United States
AU: Zandt, G
AF: Univ. of Arizona, Gould Simpson Bldg. 1040 E, Tucson, AZ 85721, United States
AB: Characterization of the highly seismically active Andean backarc is crucial for assessment of earthquake hazards in western Argentina. Moderate-to-large crustal earthquakes have caused several deaths, damage and drastic economic consequences in Argentinean history. We have studied the Andean backarc crust between 30°S and 36°S using seismic broadband data available from a previous ("the CHARGE") IRIS-PASSCAL experiment. We collected more than 12 terabytes of continuous seismic data from 22 broadband instruments deployed across Chile and Argentina during 1.5 years. Using free software we modeled full regional broadband waveforms and obtained seismic moment tensor inversions of crustal earthquakes testing for the best focal depth for each event. We also mapped differences in the Andean backarc crustal structure and found a clear correlation with different types of crustal seismicity (i.e. focal depths, focal mechanisms, magnitudes and frequencies of occurrence) and previously mapped terrane boundaries. We now plan to use the same methodology to study other regions in Argentina using near-real time broadband data available from the national seismic (INPRES) network and global seismic networks operating in the region. We will re-design the national seismic network to optimize short-period and broadband seismic station coverage for different network purposes. This work is an international effort that involves researchers and students from universities and national government agencies with the goal of providing more information about earthquake hazards in western Argentina.
DE: 7200 SEISMOLOGY
DE: 7215 Earthquake source observations (1240)
DE: 7294 Seismic instruments and networks (0935, 3025)
DE: 8108 Continental tectonics: compressional
SC: Seismology [S]
MN: 2007 Joint Assembly