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1 Dipartmento Scienze della Terra, Via S. Maria 53, I-56126 Pisa, Italy
2 Dipartmento Scienze Storiche Archeologiche e Antropologiche dell’Antichità, ‘La Sapienza’, piazzale A. Moro 5 Rome, Italy
3 Dipartmento Scienze della Terra, V. Trentino 51, 09124 Cagliari, Italy
During the Bronze Age, Vesuvius had a Plinian eruption whose deposits are known as the Avellino Pumice. The eruption spread a blanket of white and grey pumice across southern Italy, and there was a severe impact on proximal areas. Assessment of volcanological factors for the Plinian phase gives intensities of 5.7 x 107 kg s–1 for the white pumice phase and 1.7 x 108 kg s–1 for the grey pumice phase, corresponding to column heights of 23 and 31 km, respectively. Volume (magnitude) calculations using the crystal concentration method (CCM) give respectively 0.32 and 1.25 km3 of deposit, in a total minimum period of about 3 h. Archaeometric studies on Bronze Age domestic pottery from several settlements in Apulia (SE Italy) reveal the presence of pumice fragments mixed with the clay, and petrological and chemical criteria suggest that these pumices are from the Avellino eruption. This relationship allows us to fix precise correlations between different archaeological facies of the Italian Bronze Age. To explore the possibility of an extensive use of pumices in these distal regions (about 140 km from Vesuvius), we calculated the possible thickness of the tephra blanket. We propose a method to extrapolate proximal data on the deposit to calculate its minimum distal thickness. Such a method could also be used in volcanic hazard studies to assess the distal impact of large past eruptions.
