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

摘要: [1] A large (Mw 7.7) intermediate-depth earthquake occurred on 13 June 2005 in the Tarapaca region of 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 subducting slab. The 21-days aftershock distribution, constrained by a postseismic temporary array, indicates sub-horizontal fault plane lying between planes double zone an upper bound rupture area 60 Â 30 km. Teleseismic inversion shows slab-pull down dip extension mechanism nearly horizontal plane. Total geodetic moments $5.5 10 20 N.m, with averaged slip 6.5 m geodesy. peculiar that effective velocity slow, 3.5 Km.s A1 for high stress-drop, 21 –30 MPa. We propose was due to reactivation hydraulic embrittlement inherited major lithospheric plate. stress-drop suggests slab can sustain stresses. Citation: Peyrat, S., et al. (2006), 7.7, 2005, Chile): event seismologic observations, Geophys.