Imaging the rupture of the Mw 6.3 April 6, 2009 L'Aquila, Italy earthquake using back-projection of teleseismic P-waves

We present rupture details of the M-w 6.3 April 6, 2009 L'Aquila earthquake derived by back-projecting teleseismic P waves. This technique has previously been applied to large magnitude earthquakes, but this is the first application to a moderate size event. We processed vertical-component seismograms for 60 broadband stations obtained from the Incorporated Research Institutions for Seismology (IRIS) data center. The traces were aligned and normalized using a multi-channel cross-correlation algorithm and 4th root stacking was used to image the rupture. We found that the L'Aquila earthquake ruptured towards the south and that a second discrete pulse of energy occurred 20-25 km east of the epicenter about 17-18 s after the nominal origin time. The spatial extent of the rupture image correlates well with a post-seismic survey of damage in the region. Because the technique is potentially very fast (images can be produced within 20-30 minutes of the origin time), it may be useful to governmental agencies tasked with emergency response and rescue. Citation: D'Amico, S., K. D. Koper, R. B. Herrmann, A. Akinci, and L. Malagnini (2010), Imaging the rupture of the M-w 6.3 April 6, 2009 L'Aquila, Italy earthquake using back-projection of teleseismic P-waves, Geophys. Res. Lett., 37, L03301, doi:10.1029/2009GL042156.