Tsunamis generated by coastal and submarine landslides in the Mediterranean Sea

Abstract

The main cause of tsunami generation in the Mediterranean Sea is tectonic activity associated with strong earthquakes. However, tsunami waves are also generated by landslides. From a compilation of 32 reliable cases of landslide tsunamis it comes out that most of them were caused by subaerial landslides or marine slides induced mainly by earthquakes and less frequently by volcanic eruptions. Others were caused by gravitative landslides or marine slides. The most frequent events were observed in the Corinth Gulf, Greece (11 out of 32 cases). In the volcanic Aeolian islands, Italy, 7 out of 32 cases were reported. In the Hellenic arc only 3 events are known, in contrast to the abundant, large-size tsunamis of seismotectonic origin historically documented. In Cyclades, South Aegean, only 2 but large landslide tsunamis were reported. Only few events have occurred in Marmara Sea, Cyprus, East Sicily, Liguria-Côte d'Azur and Algeria. Such a pattern of geographical distribution makes possible to assess the potential for landslide tsunami generation.