Rupture process and coseismic deformations of the 27 February 2010 Maule earthquake, Chile

We estimated the spatial and temporal slip distribution for the 27 February 2010 Maule earthquake from teleseismic body wave data. To obtain a stable inversion solution, we used the data covariance matrix from the observation and modeling errors, incorporated smoothing constraints and determined their optimal values by using the Akaike Bayesian Information Criterion (ABIC). The fault rupture can be divided into three stages. For the first 30 s the rupture started as an elliptical crack elongated in the in-plane direction along the dip. After 30 s the rupture propagated bi-laterally along strike reaching the maximum moment release rate at around 50 s near the hypocenter. Finally the rupture propagated mainly to the north reaching another peak of moment release rate at 80 s and 130 km north-east from the hypocenter. Main rupture lasted for about 110 s. In order to evaluate our source model, we calculated the predicted coseismic vertical displacements and compare them with observed uplift/subsidence values measured along the coastline, as well as displacements obtained from strong ground motion and high-sampling GPS records in Concepcion. Our model provides good estimations of the static displacements in the northern source region, but under-estimates the coseismic uplifts in the southern region.