The event generated along a seismogenic structure covered by the sediments of the Po plane. The focal mechanism is clearly reversal. Figure 1 shows the focal mechanism and location proposed by INGV and the stations used to obtain the corresponding result.
The detailed information using in the regression can be seeing in the INGV website at the following link: http://ismd.mi.ingv.it/evento_35.php?var1=772691&path=120520020352 (link updated in 2018)
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| Figure 1. Epicenter (red star) and focal mechanism proposed by the INGV. The stations used to obating the mechanism are shown as red triangles. |
Figure 2 shows the main event and the cluster of aftershocks until the 22th of May at 18:00. The focal mechanism of the main aftershocks are shown in the figure, all of them are showing reverse faulting type.
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| Figure 2. Main event of the 20th of May and its aftershocks cluster. The focal mechanims of the main aftershoks are shown (EMSC, 2012; http://www.emsc-csem.org/Files/event/267440/M6.1-North-Italy-Seismicity.jpg). | |
Figure 3 shows the seismotectonics of the region and trys to correlate the main faults shown by Boccaletti et al. (2004) with the aftershocks cluster.
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| Figure 3. Seismotectonics of the region (Boccaletti et al., 2004). |
According to the European-Mediterranean Seismological Centre (EMSC) (http://www.emsc-csem.org/Earthquake/209/M-6-1-NORTHERN-ITALY-on-May-20th-2012-at-02-03-UTC), the number of aftershocks and their relative magnitude sixty hours after the main shocks are shown in Table 1.
| Table 1 |
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Boccaletti, M.; Bonini, M.; Corti, G.; Gasperini, P.; Martelli, L.; Piccardi, L.; Tanini, C. and Vannucci, G.; (2004), La carta sismotettonica della regione Emilia-Romagna Scala 1:250,000. Servizio Geologico Sismico e dei Suoli.
