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1 Earth Science Department, University of Pisa, via S. Maria 53, I-56126, Pisa, Italy
2 Institute of Geology and Mineral Exploration, 70 Messogion, 11527, Athens, Greece
3 Earth Science Department, University of Cagliari, via Trentino 51, I09124, Cagliari, Italy
Volcanological studies in the Bronze Age settlement of Akrotiri (Santorini, Greece) and in the Roman towns of Pompeii and Herculaneum (Vesuvius, Italy) have provided information about the precursory phenomena preceding the Minoan and AD 79 Plinian eruptions and the impact of the eruptive products on the human settlements. The Akrotiri settlement was badly damaged by earthquakes before the onset of the eruption. A building debris layer, related to these earthquakes, covers the Minoan soil. The fallout pumice bed, mantling the ruins, freezes a state of partial destruction of the settlement. The deposition of the following pyroclastic flows completed the covering of the site. Strong seismicity also occurred during the opening and the Plinian phases. At the Herculaneum and Pompeii excavations clear evidence of strong pre- and syn-eruptive earthquakes is absent. Herculaneum, just 7 km west of the crater of Vesuvius, was destroyed by several pyroclastic flows, which buried the town under 20 m of deposits. Pompeii was covered by a 3 m thick blanket of pumice fall deposit. Distal dilute and turbulent ash clouds reached the town toward the end of the Plinian phase, killing all remaining inhabitants. The following turbulent cloud related to the onset of the caldera collapse completely destroyed the town, which was successively covered by the final phreatomagmatic products of the eruption.
