The 2010 Mw 8.8 Maule Megathrust Earthquake of Central Chile, Monitored by GPS

Rupture kinematics of this very large earthquake were obtained from high-resolution Global Positioning System data. Large earthquakes produce crustal deformation that can be quantified by geodetic measurements, allowing for the determination of the slip distribution on the fault. We used data from Global Positioning System (GPS) networks in Central Chile to infer the static deformation and the kinematics of the 2010 moment magnitude (Mw) 8.8 Maule megathrust earthquake. From elastic modeling, we found a total rupture length of ~500 kilometers where slip (up to 15 meters) concentrated on two main asperities situated on both sides of the epicenter. We found that rupture reached shallow depths, probably extending up to the trench. Resolvable afterslip occurred in regions of low coseismic slip. The low-frequency hypocenter is relocated 40 kilometers southwest of initial estimates. Rupture propagated bilaterally at about 3.1 kilometers per second, with possible but not fully resolved velocity variations.

[1]  C. Darwin,et al.  Narrative of the Surveying Voyages of His Majesty's Ships Adventure and Beagle, Between the Years 1826 and 1836 , 2011 .

[2]  John McCloskey,et al.  Limited overlap between the seismic gap and coseismic slip of the great 2010 Chile earthquake , 2011 .

[3]  Masanobu Shimada,et al.  The 2010 Maule, Chile earthquake: Downdip rupture limit revealed by space geodesy , 2010 .

[4]  Chen Ji,et al.  Afterslip of the 2010 Chilean earthquake , 2010 .

[5]  Anne Socquet,et al.  Asperities and barriers on the seismogenic zone in North Chile: state‐of‐the‐art after the 2007 Mw 7.7 Tocopilla earthquake inferred by GPS and InSAR data , 2010 .

[6]  M. Moreno,et al.  2010 Maule earthquake slip correlates with pre-seismic locking of Andean subduction zone , 2010, Nature.

[7]  J. Nocquet,et al.  Slip distribution of the February 27, 2010 Mw = 8.8 Maule Earthquake, central Chile, from static and high‐rate GPS, InSAR, and broadband teleseismic data , 2010 .

[8]  D. Melnick,et al.  Land-Level Changes Produced by the Mw 8.8 2010 Chilean Earthquake , 2010, Science.

[9]  Hiroo Kanamori,et al.  Teleseismic inversion for rupture process of the 27 February 2010 Chile (Mw 8.8) earthquake , 2010 .

[10]  R. Madariaga,et al.  Central Chile Finally Breaks , 2010, Science.

[11]  Robert Smalley,et al.  High-rate GPS: How High Do We Need to Go? , 2009 .

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

[13]  Z. Altamimi,et al.  ITRF2005 : A new release of the International Terrestrial Reference Frame based on time series of station positions and Earth Orientation Parameters , 2007 .

[14]  Kristine M. Larson,et al.  Recovering Seismic Displacements through Combined Use of 1-Hz GPS and Strong-Motion Accelerometers , 2007 .

[15]  Chalermchon Satirapod,et al.  Insight into the 2004 Sumatra–Andaman earthquake from GPS measurements in southeast Asia , 2005, Nature.

[16]  R. Bilham,et al.  A Flying Start, Then a Slow Slip , 2005, Science.

[17]  Gerd Gendt,et al.  The International GPS Service: Celebrating the 10th anniversary and looking to the next decade , 2005 .

[18]  Paul Bodin,et al.  Using 1-Hz GPS Data to Measure Deformations Caused by the Denali Fault Earthquake , 2003, Science.

[19]  A. Rietbrock,et al.  The Southern Andes between 36° and 40°S latitude: seismicity and average seismic velocities , 2002 .

[20]  R. Madariaga,et al.  A seismological study of the 1835 seismic gap in south-central Chile , 2002 .

[21]  Dimitar Dimitrov,et al.  Interseismic strain accumulation in south central Chile from GPS measurements, 1996–1999 , 2002 .

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

[23]  M. Yamano,et al.  The seismogenic zone of subduction thrust faults , 1997 .

[24]  James L. Davis,et al.  Geodesy by radio interferometry: The application of Kalman Filtering to the analysis of very long baseline interferometry data , 1990 .

[25]  Y. Okada.  Surface deformation due to shear and tensile faults in a half-space , 1985 .

[26]  Stuart P. Nishenko,et al.  Seismic potential for large and great interplate earthquakes along the Chilean and Southern Peruvian Margins of South America: A quantitative reappraisal , 1985 .

[27]  F. D. M. D. Ballore.  Historia sísmica de los Andes Meridionales al sur del paralelo XVI. Sexta parte. Conclusión) , 1916 .

[28]  Charles Darwin,et al.  Journal of Researches Into the Natural History and Geology of the Countries Visited During the Voyage of H.M.S. 'Beagle' Round the World ... , 2006 .