Crustal deformation associated to the M 8.8 Maule earthquake in central Chile, 27 February 2010, detected by permanent GPS stations in Argentina

L. MENDOZA; J. VASQUEZ; D. DEL COGLIANO

Mar del Plata

Congreso; International Geological and Geophysical Congress on the Southern Hemisphere; 2010

The analysis of records from permanent GPS stations registered before, during and after an earthquake provides direct measurements of the co-seismic offsets and the post-seismic deformation associated to the seismic event. The magnitude and distribution of the observed deformation may help to infer the nature of the fault at depths; on the long term the post-seismic relaxation observed by GPS could be useful to other techniques (e.g. fit together InSAR scenes).On the other hand, the co-seismic displacements and the post-seismic velocities of the GPS stations are required in order to evaluate the impact of the earthquake on the regional geodetic infrastructure itself and to assure, if necessary, a smooth redefinition of the affected geodetic networks; this situation necessarily concerns to not scientific applications including the surveying, the engineering and the land registry.We present results from a consistent processing of GPS records, spanning 16 months and centred around the M 8.8 Maule earthquake in central Chile (27 February 2010), involving permanent GPS stations from the RAMSAC network (Argentina) and GPS stations from the SIRGAS-CON and the IGS tracking networks. The magnitude and spatial distribution of the observed deformation are presented and discussed, with special attention to the implication for the geodetic infrastructure of the country.