The historical record of pyroclastic density currents at Stromboli and perspective for future hazard assessment

Abstract

The formation of pyroclastic density currents (PDC) at Stromboli has been described several times. PDCs are associated with paroxysms, lava emissions and commonly confined into the Sciara del Fuoco (SdF). At least during 1906, 1930 and 1944 paroxysms PDCs were produced on the flanks of Stromboli, out of the SdF. PDCs flowed in valleys cut on the volcano flanks and reached the sea producing vast deltas. In 1930 two flows reached the Stromboli village causing victims. During the 3 July paroxysm, pyroclastic material was emplaced on steep slopes right above the village of Ginostra and small avalanches of incandescent rocks were produced. In light of recent events, PDCs were produced also inside the SdF, reached the sea and continued to flow over the water for several hundred meters. PDCs potentially represent the most dangerous manifestation of volcanic activity at Stromboli and need a proper hazard assessment.