Numerical Study on the Role of Basin Geometry and Kinematic Seismic Source in 3D Ground Motion Simulation of the 22 February 2011 MW 6.2 Christchurch Earthquake

The main aim of this paper was to perform 3D numerical simulations of the MW 6.2 Christchurch earthquake on 22 February 2011, the most devastating and deadliest event of the seismic sequence that struck the Canterbury Plains, and particularly the city of Christchurch, between September 2010 and June 2011, and to compare the numerical results with strong ground motion observations. The numerical simulations of seismic wave propagation within the Canterbury Plains, where widespread damage was recognized during the post-earthquake reconnaissance surveys, were performed by means of the Spectral Element code GeoELSE (http://geoelse.stru.polimi.it), combining the following features: 1) two different kinematic finite fault models, provided by INGV and GNS seismic source inversion studies, and 2) two simplified models for the description of the interface between the stiff volcanic rock of the Banks Peninsula and the soft materials within the Canterbury Plains.