Teleseismic inversion for rupture process of the 27 February 2010 Chile (Mw 8.8) earthquake

The 27 February 2010 Chile (M_w 8.8) earthquake is the fifth largest earthquake to strike during the age of seismological instrumentation. The faulting geometry, slip distribution, seismic moment, and moment-rate function are estimated from broadband teleseismic P, SH, and Rayleigh wave signals. We explore some of the trade-offs in the rupture-process estimation due to model parameterizations, limited teleseismic sampling of seismic phase velocities, and uncertainty in fault geometry. The average slip over the ~81,500 km^2 rupture area is about 5 m, with slip concentrations down-dip, up-dip and southwest, and up-dip and north of the hypocenter. Relatively little slip occurred up-dip/offshore of the hypocenter. The average rupture velocity is ~2.0–2.5 km/s.

[1]  Dimitar Dimitrov,et al.  Interseismic strain accumulation measured by GPS in the seismic gap between Constitución and Concepción in Chile , 2009 .

[2]  Hiroo Kanamori,et al.  Use of long-period surface waves for rapid determination of earthquake-source parameters , 1981 .

[3]  S. Beck,et al.  Source characteristics of historic earthquakes along the central Chile subduction Askew et alzone , 1998 .

[4]  Peter M. Shearer,et al.  Extent, duration and speed of the 2004 Sumatra–Andaman earthquake imaged by the Hi-Net array , 2005, Nature.

[5]  FAST TRACK PAPER: The reflection seismic survey of project TIPTEQ-the inventory of the Chilean subduction zone at 38.2° S , 2008 .

[6]  D. Lange,et al.  Structure of the seismogenic zone of the southcentral Chilean margin revealed by local earthquake traveltime tomography , 2009 .

[7]  T. Lay,et al.  Rapid estimation of first‐order rupture characteristics for large earthquakes using surface waves: 2004 Sumatra‐Andaman earthquake , 2006 .

[8]  John C. VanDecar,et al.  Determination of teleseismic relative phase arrival times using multi-channel cross-correlation and least squares , 1990 .

[9]  K. Koper,et al.  Rupture imaging of the Mw 7.9 12 May 2008 Wenchuan earthquake from back projection of teleseismic P waves , 2009 .

[10]  H. Kanamori,et al.  Effects of Kinematic Constraints on Teleseismic Finite-Source Rupture Inversions: Great Peruvian Earthquakes of 23 June 2001 and 15 August 2007 , 2009 .

[11]  Hiroo Kanamori,et al.  Source inversion of W phase: speeding up seismic tsunami warning , 2008 .

[12]  H. Spall.  Earthquake prediction research at the Seismological Laboratory, California Institute of Technology , 1979 .