Coseismic deformation and source modeling of the May 2012 Emilia (Northern Italy) earthquakes

Online Material: Additional figures and tables. On 20 May 2012, an M L 5.9 earthquake (Table 1) occurred near the town of Finale Emilia, in the central Po plain, Northern Italy (Fig. 1a). The mainshock caused seven casualties and the collapse of several historical buildings and industrial sheds. The earthquake sequence continued with diminishing aftershock magnitudes until 29 May, when an M L 5.8 earthquake occurred near the town of Mirandola, ∼12  km west‐southwest of the mainshock (Scognamiglio et al. , 2012). This second mainshock started a new aftershock sequence in this area, and increased structural damage and collapses, causing 19 more casualties and increasing to 15,000 the number of evacuees. View this table: Table 1 Largest Earthquakes ( M L>5) of the 2012 Emilia Seismic Sequence (http://iside.rm.ingv.it) Figure 1. (a) Geostructural setting of the Emilia 2012 seismic sequence area showing the vertically projected top traces of the main thrust fault planes, and the anticlinal axes, modified after (Bigi et al. , 1983; Boccaletti et al. , 2010; Picotti and Pazzaglia, 2008); white dots, aftershock epicenters. Large instrumental and historical earthquakes are also shown (http://iside.rm.ingv.it, last accessed April 2013); Rovida et al. , 2011); yellow rectangles, footprint of the COSMO‐SkyMed (CSK) and Radarsat satellite image pairs. The focal mechanisms of the two main events (from Malagnini et al. , 2012) are reported in the map. (b) Geological profiles interpreted from seismic reflection data after (Boccaletti et al. , 2010) corresponding to traces A and B in (a). Shortly after the first mainshock, the Department of Civil Protection (DPC) activated the Italian Space Agency (ASI), which provided post‐seismic Synthetic Aperture Radar (SAR) Interferometry data coverage with all four Constellation of Small Satellites for the Mediterranean Basin Observation (COSMO‐SkyMed) SAR satellites. Within the next two weeks, several SAR Interferometry (InSAR) image pairs were processed by the Istituto Nazionale di Geofisica e Vulcanologia–Space‐based Monitoring System …