Source of the 1693 Catania earthquake and tsunami (southern Italy): New evidence from tsunami modeling of a locked subduction fault plane

Abstract

[1] The 1693 Catania earthquake, which caused 60000 deaths in eastern Sicily and generated a 5 -10 m high tsunami, is investigated. GPS data indicate ESE-WNW convergence in the Calabrian arc at 4 -5 mm/yr. New highresolution seismic data image active compression at the toe of the accretionary wedge. The lack of instrumentally recorded thrust earthquakes suggests the presence of a locked subduction fault plane. Thermal modeling is applied to calculate the limits of the seismogenic zone. Tsunami modeling is performed to test the hypothesis that the 1693 earthquake occurred on the subduction fault plane (160 Â 120 km in size) with 2 m of mean co-seismic slip. This source successfully reproduces historical observations with regard to polarity and predicts 1 -3 m high amplitudes. It is likely that only the SW segment of the subduction fault plane ruptured in 1693 and 1169, implying a recurrence interval of roughly 500 years for similar events.

Active faults and historical earthquakes in the Messina Straits area (Ionian Sea)

“…GPS measurements of Calabrian site motion relative to Apulia show systematic residuals directed towards the Ionian Sea. This suggests active crustal compression and an outward motion of the CA as a result of active subduction and shortening taken up in the accretionary wedge, eventually accommodated by long-term slip on the subduction interface (Gutscher et al, 2006;D'Agostino et al, 2008). The submerged portion of the CA consists of a NW thickening wedge of deformed sediments (Finetti 1982;Cernobori et al, 1996;Minelli and Faccenna, 2010) overlying, in the most external portion, NW dipping sediments and the basement.…”

“…The CA subduction complex, in fact, is part of the most active seismic belt of the central Mediterranean region; it faces the highly populated regions of southern Italy, which were struck repeatedly by large magnitude earthquakes in the recent past (Bottari et al, 1989;Jacques et al, 2001;Galli and Bosi, 2003;Gutscher et al, 2006;Jenny et al, 2006), often associated with destructive tsunamis (Piatanesi and Tinti, 1998;Tinti et al, 2004). For several major earthquakes in the region, like the 1908 (Mulargia and Boschi, 1983;Bottari et al, 1986;Capuano et al, 1988;De Natale and Pingue, 1991;Amoruso et al, 2002;Pino et al, 2009) and 1693 (Bianca et al, 1999;Sirovich and Pettenati, 1999;Monaco and Tortorici, 2000;Gutscher et al, 2006), it has Polonia et al (2011). Slip vector in the African reference frame is indicated by a red arrow.…”

Applicability of the Decision Matrix of North Eastern Atlantic, Mediterranean and connected seas Tsunami Warning System to the Italian tsunamis

“…Both tsunamis have been the object of intense research in recent years and hypotheses have been advanced that their source was not exclusively the earthquake, but also some landslides in the Hyblean-Malta escarpment, and in the Messina Straits or on the Mt. Etna offshore complex, respectively (Tinti et al, 1999(Tinti et al, , 2001Gutscher et al, 2006;Favalli et al, 2009;Billi et al, 2010;Argnani et al, 2012). Such debate has no relevance in this context, since, whatever the real cause, there is no doubt that the DM predictions are adequate.…”

The UBO-TSUFD tsunami inundation model: validation and application to a tsunami case study focused on the city of Catania, Italy

“…Tsunami observations (Baratta, 1901;Tinti et al, 2004) and tsunami modelling suggest that the source should be located offshore (Tinti et al, 2001) and a number of hypotheses have been proposed in literature on a possible offshore fault rupture (see e.g. Bianca et al, 1999;Sirovich and Pettenati, 1999;Monaco and Tortorici, 2000;Argnani et al, 2005;Gutscher et al, 2006). The most promising rupture area seems to be located along the Hyblaean-Malta escarpment since it provides the best fit with tsunami observations in terms of first wave polarity and wave amplitude (Tinti and Armigliato, 2003).…”