Aftershock seismicity of the 2010 Maule Mw=8.8, Chile, earthquake: Correlation between co-seismic slip models and aftershock distribution? - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Geophysical Research Letters Année : 2012

Aftershock seismicity of the 2010 Maule Mw=8.8, Chile, earthquake: Correlation between co-seismic slip models and aftershock distribution?

Résumé

The 27 February 2010 Maule, Chile (Mw=8.8) earthquake is one of the best instrumentally observed subduction zone megathrust events. Here we present locations, magnitudes and cumulative equivalent moment of the first $2 months of aftershocks, recorded on a temporary network deployed within 2 weeks of the occurrence of the main-shock. Using automatically-determined onset times and a back projection approach for event association, we are able to detect over 30,000 events in the time period analyzed. To further increase the location accuracy, we systematically searched for potential S-wave arrivals and events were located in a regional 2D velocity model. Additionally, we calculated regional moment tensors to gain insight into the deformation history of the aftershock sequence. We find that the aftershock seismicity is concentrated between 40 and 140 km distance from the trench over a depth range of 10 to 35 km. Focal mechanisms indicate a predominance of thrust faulting, with occasional normal faulting events. Increased activity is seen in the outer-rise region of the Nazca plate, predominantly in the northern part of the rupture area. Further down-dip, a second band of clustered seismicity, showing mainly thrust motion, is located at depths of 40-45 km. By comparing recent published mainshock source inversions with our aftershock distribution, we discriminate slip models based on the assumption that aftershocks occur in areas of rapid transition between high and low slip, surrounding high-slip regions of the mainshock.
Fichier principal
Vignette du fichier
Rietbrock_Maule_GRL.pdf (2.17 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-02057777 , version 1 (25-10-2019)

Identifiants

Citer

A. Rietbrock, I. Ryder, G. Hayes, C. Haberland, D. Comte, et al.. Aftershock seismicity of the 2010 Maule Mw=8.8, Chile, earthquake: Correlation between co-seismic slip models and aftershock distribution?. Geophysical Research Letters, 2012, 39 (8), pp.L08310. ⟨10.1029/2012gl051308⟩. ⟨hal-02057777⟩
60 Consultations
97 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More