Source parameters of the 1908 Messina Straits, Italy, earthquake from geodetic and seismic data

Abstract

[1] We carry out a nonlinear joint inversion of P wave first-motion polarities and coseismic surface displacement data of the 1908 Messina earthquake. We model the earthquake using a single planar fault: Slip is at first assumed to be uniform across the whole fault, then independent in a small set of coplanar subfaults, and finally smoothly variable across the fault. The first two steps are accomplished using a global minimization technique. The main features of the retrieved model are very robust and independent of the seismic velocity profile, of the presence of questionable bench marks, and of the assumed residual distribution. The along-strike component of slip is about half the along-dip component, in agreement with the direction of the extensional stress axis retrieved from geological observations. Surface vertical displacement is consistent with tsunami data and with the morphology of the Messina Straits.

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

“…On the other hand, other models such as those by Amoruso et al (2002) and Capuano et al (1988) suggest a causative fault striking N or N5W, closer to that described in this work. The main effect at the seafloor after the 1908 earthquake was subsidence affecting the entire Messina Straits, but was concentrated mainly in the southern part, where the Messina Strait is wider and opens to the Ionian Sea.…”

“…Although it is generally agreed that the earthquake was the result of normal faulting in the Messina Straits, there are uncertainties over the specific location and throw of the causative fault. Several models of seismic source have been proposed (Schick, 1977;Valensise and Pantosti, 1982;Mulargia and Boschi, 1983;Bottari et al, 1986;Capuano et al, 1988;De Natale and Pingue, 1991;Amoruso et al, 2002), but to date, none of them has been able to fully explain the tsunami observations associated with the event (Pino et al, 2009). Some uncertainties affect also the origin and reconstruction of the 1908 tsunami; its source area was reconstructed by Billi et al (2008) using runup information and the delay between the earthquake and tsunami arrivals along the Calabrian and Sicilian coasts (Omori, 1909;Platania, 1909;Baratta, 1910).…”

“…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.…”

Earthquake and People: The Maltese Experience of the 1908 Messina Earthquake

“…The 1908 earthquake may have been caused by the activation of a normal fault located in the Messina Straits, but the exact location and geometry of the fault are still controversial (Boschi et al 1989;Bottari et al 1989;Valensise and Pantosti 1992;Monaco and Tortorici 2000, Amoruso et al 2002, 2006DISS Working Group 2007;Pino et al 2009). The low level of seismicity in the Messina Straits in the last few decades (Neri et al 2003(Neri et al , 2004(Neri et al , 2008 has not permitted seismologists to define the locations and mechanisms of the seismogenic faults in this area.…”

Simulation systems for tsunami wave propagation forecasting within the French tsunami warning center

“…The Messina (Sicily) earthquake of 1908, with an estimated seismic moment of M o = 5.10 19 N m, is the largest event to have hit the Italian coasts during the last century (e.g., Tinti et al, 1999;Amoruso et al, 2002Amoruso et al, , 2006). An estimated total of 60 000 people were killed and extensive damage was recorded in Sicily and Calabria.…”