Dati geomorfologici, geocronologici e d’archivio nella identificazione dell’impatto di maremoti storici

Italian coasts are marked by sediments and landforms which suggest the impact of catastrophic marine processes like tsunamis. They are represented by: i – large boulders weighing more than a ton, which can be found isolated, sparse in fields or arranged in belts; ii – marine sand/silt layers interbedded with backdune/coastal swamp; iii – anomalous strata placed inside shelf depositional sequence; iv – large washover fans in backdune areas. Recent research carried out along the Mediterranean coasts recognized the geological evidence of at least 15 different tsunamis occurred during the last 6000 years. Chronological data related to these events have been obtained by C14/AMS analysis performed on biogenic material associated to tsunami sediments and forms. Unfortunately, absolute age determinations yield a more or less wide range of age. Then, it is not possible to single out a seismic event responsible for tsunami generation without compared absolute age data to historical chronicle and archive data.