A REVISION OF THE 1693 EASTERN SICILY EARTHQUAKE AND TSUNAMI

The 1693 earthquake was a disastrous event affecting eastern Sicily, s outhern Italy, where it caused over 60,000 victims and total destructi on of several villages and towns in the districts of Siracusa, Ragusa, and Catania. The earthquake was followed by a tsunami that struck the Ionian coasts of Sicily and the Messina Strait and was probably obser ved even in the Aeolian Islands. Historical documents on sea waves and flooding, though not abundant, allow us to form a picture of the tsun ami first attack and inundation. The first water movement all along th e Sicilian coastline was a strong sea withdrawal, followed by a violen t sea return and coastal flooding. The main purpose of this research i s to put constraints on the focal mechanism of this earthquake on the basis of the available documents on the tsunami (1) by simulating tsun ami from different possible sources via numerical modeling based on fi nite element technique and shallow water approximation and (2) by choo sing the source best fitting the tsunami data as the most plausible ca use for this tsunami. The relevance of this study should also be evalu ated in light of the circumstance that no certain indication on the ea rthquake fault can be deduced from the available macroseismic data alo ne. Solving the source problem for this event, one of the largest occu rring in southeastern Sicily in historical times, is a significant con tribution to understanding the seismotectonic regime of the region and to assessing the related earthquake and tsunami hazard/risk with impl ications on mitigation policies.