Prolonged post-seismic deformation of the 1960 great Chile earthquake and implications for mantle rheology

Contemporary crustal deformation of the southern Andean margin shows an interesting feature: While nearly all coastal GPS sites move landward, consistent with interseismic deformation near a locked subduction fault, sites 300-400 km landward of the rupture region of the M-w 9.5 1960 Chile earthquake...

Descripción completa

Detalles Bibliográficos
Autores: Khazaradze, Giorgi, Wang, K., Klotz, J., Hu, Y., He, J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/163191
Acceso en línea:https://hdl.handle.net/2445/163191
Access Level:acceso abierto
Palabra clave:Subducció
Terratrèmols
Xile
Subduction
Earthquakes
Chile
Descripción
Sumario:Contemporary crustal deformation of the southern Andean margin shows an interesting feature: While nearly all coastal GPS sites move landward, consistent with interseismic deformation near a locked subduction fault, sites 300-400 km landward of the rupture region of the M-w 9.5 1960 Chile earthquake are moving in the opposite direction. We attribute the seaward motion of these inland sites to a prolonged crustal deformation due to mantle stress relaxation following the 1960 great earthquake. In order to reproduce the observed seaward motion using a three-dimensional finite element model we need to incorporate a mantle viscosity of about 3 x 10(19) Pa s. The possibility that the seaward motion is caused by a silent slip event on the plate interface at large depths cannot be completely excluded, and our analysis provides a working model for future field tests.