Si el mundo cientifo, estaba en alerta, Por que no se educo a las comunidades de las zonas para enfrentar una posible catastrofe, fue mas fuerte el temor a la eqivocacion que la responsabilidad sobre las vidas, Que importa equivocarse si pudo salvarse vidas, por que no se compraron Tel. satelitales para las alcaldias, mas alarmas de maremotos en las playas, mas preparacion de la gente, mas equipos para ir en ayuda, si algo ya venia NO ENTIENDO, siempre en Chile queremos bajar el perfil a todo.

ESTO NO PUEDE VOLVER A PASAR, LAS INSTITUCIONES DEBEN PREPARAR A LA GENTE  PARA LO PEOR, AHORA  QUE VALE, SI YA LOS MUERTOS  NO PUEDEN VOLVER....EN 20 0 30 AÑOS MAS ESTO VOLVERA A PASAR, UN NUEVO TERREMOTO ES POSIBLE QUE VUELVA, PUES LA HISTORIA DE ELLOS ES CICLICA, OJALA ESE DIA LAS AUTORIDADES HAYAN TOMADO MEDIDAS, QUE HOY NO SE TOMARON. OJALA  LA COMUNIDAD CIENTIFICA  TENGA ESPACIOS  PARA HABLAR CON LA  GENTE  Y ASI SALVEMOS VIDAS...OJALA EN EL NORTE  APRENDAN DE LOS ERRORES  DEL SUR, Y NO ESPEREN QUE ALGO PASE PARA DECIR  NOS EQUIVOCAMOS...UNA POBLACION EDUCADA  E INFORMADA, SIEMPRE PODRA TOMAR DECISIONES, QUE UNA DESINFORMADA NO PUEDE HACER

Ab s t r a c t.

The Concepción–Constitución area [35–37◦S] in South Central Chile is very likely a mature seismic gap, since no large subduction earthquake has occurred there since 1835. Three campaigns of global positioning system (GPS) measurements were carried out in this area in 1996, 1999 and 2002. We observed a network of about 40 sites, including two east–west transects ranging from the coastal area to the Argentina border and one north–south profile along the coast. Our measurements are consistent with the Nazca/South America relative angular velocity (55.9◦N, 95.2◦W, 0.610◦/Ma) discussed by Vigny et al. (2008, this issue) which predicts a convergence of 68mm/year oriented 79◦N at the Chilean trench near 36◦S. With respect to stable South America, horizontal velocities decrease from 45mm/year on the coast to 10mm/year in the Cordillera. Vertical velocities exhibit a coherent pattern with negative values of about 10mm/year on the coast and slightly positive or near zero in the Central Valley or the Cordillera.

Horizontal velocities have formal uncertainties in the range of 1–3mm/year and vertical velocities around 3–6mm/year. Surface deformation in this area of South Central Chile is consistent with a fully coupled elastic loading on the subduction interface at depth. The best fit to our data is obtained with a dip of 16±3◦, a locking depth of 55±5 km and a dislocation corresponding to 67mm/year oriented 78◦N. However in the northern area of our network the fit is improved locally by using a lower dip around 13◦. Finally a convergence motion of about 68mm/year represents more than 10mof displacement accumulated since the last big interplate subduction event in this area over 170 years ago (1835 earthquake described by Darwin).

Therefore, in a worst case scenario, the area already has a potential for an earthquake of magnitude as large as 8–8.5, should it happen in the near future.

© 2009 Elsevier B.V. All rights reserved.

(disponible en: http://www.sciencedirect.com/science/journal/00319201).