Skip to Main content Skip to Navigation
Journal articles

Tarapacá intermediate-depth earthquake (Mw 7.7, 2005, northern Chile): A slab-pull event with horizontal fault plane constrained from seismologic and geodetic observations

Abstract : [1] A large (Mw 7.7) intermediate-depth earthquake occurred on 13 June 2005 in the Tarapacá region of the northern Chile seismic gap. Source parameters are inferred from teleseismic broadbands, strong motions, GPS and InSAR data. Relocated hypocenter is found at $98 km depth within the subducting slab. The 21-days aftershock distribution, constrained by a postseismic temporary array, indicates a sub-horizontal fault plane lying between the planes of the double seismic zone and an upper bound of the rupture area of 60 km  30 km. Teleseismic inversion shows a slab-pull down dip extension mechanism on a nearly horizontal plane. Total seismic and geodetic moments are $5.5  10 20 N.m, with an averaged slip of 6.5 m from geodesy. The earthquake rupture is peculiar in that the effective velocity is slow, 3.5 Km.s À1 for a high stress-drop, 21 –30 MPa. We propose that rupture was due to the reactivation by hydraulic embrittlement of a inherited major lithospheric fault within the subducting plate. The stress-drop suggests that the region of the slab between planes of the double seismic zone can sustain high stresses. Citation: Peyrat, S., et al. (2006), Tarapacá intermediate-depth earthquake (Mw 7.7, 2005, northern Chile): A slab-pull event with horizontal fault plane constrained from seismologic and geodetic observations, Geophys.
Document type :
Journal articles
Complete list of metadatas

Cited literature [26 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-01285695
Contributor : Eva Fareau <>
Submitted on : Thursday, March 10, 2016 - 10:35:26 AM
Last modification on : Wednesday, July 8, 2020 - 5:24:05 PM
Long-term archiving on: : Monday, June 13, 2016 - 9:07:33 AM

File

grl7710.pdf
Publisher files allowed on an open archive

Identifiers

Citation

S Peyrat, J Campos, Jean-Bernard de Chabalier, S Bonvalot, M.-P Bouin, et al.. Tarapacá intermediate-depth earthquake (Mw 7.7, 2005, northern Chile): A slab-pull event with horizontal fault plane constrained from seismologic and geodetic observations. Geophysical Research Letters, American Geophysical Union, 2006, ⟨10.1029/2006GL027710⟩. ⟨insu-01285695⟩

Share

Metrics

Record views

1283

Files downloads

1052