Analysis of large boulders along the coast of south-eastern Sicily: storm or tsunami deposits?

We investigate boulder accumulations at Vendicari (SE Sicily) to discriminate their deposition source: storms or tsunamis. Using the significant wave height and period of maximum observed storms and of the 1693 and 1908 tsunamis along the Ionian coast, the approximate transport limit of boulders by these waves was estimated. Results show that the largest storms were probably responsible for the current distribution of most boulders, whereas the boulders at distance > 40 m are likely deposited by tsunamis. The significant difference between storm and tsunami waves is not breaking wave height but wave period affecting wave attenuation and then flooding and transport distance.