Identification of paleotsunami deposits in the Augusta Bay area (eastern Sicily, Italy): paleoseismological implication

In this paper we present the geological evidence of paleotsunamis in the Augusta area together with some paleoseismological implication derived from the discovery of multiple inundation events. It is well known that eastern Sicily has been affected in historical time by large earthquakes (CPTI Working group, 2004) and its southern sector in particular was strongly hit by the 1693 and 1169 events that were followed by devastating tsunamis. The Augusta Bay area is one of the locations where the information available from historical reports on tsunami effects (hit localities, inundated areas and run-up distribution) stimulated our curiosity in searching for the geological signature of tsunamis. The research was carried out through a multi-theme approach consisting of historical studies, geomorphological and geological surveys, coring campaigns, laboratory analyses (paleontological, radiometric, SEM, X-Ray, susceptibility, tephra, etc.). We mainly concentrated on marsh or lagoon areas where both the chance of tsunami deposit sedimentation/preservation and the possibility of finding datable material are expected to be quite high for coring survey. This preliminary work was based on a detailed geomorphological study of the whole Augusta Bay coast line, through aerial-photographs and satellite images interpretation and field surveys.