L’impatto delle eruzioni tardo oloceniche del Somma-Vesuvio sul paesaggio e le attività umane. Una sintesi di dati geoarcheologici

In this paper are shown the geoarchaeological results of a pluridisciplinary research carried out on the Campanian archaeological sites, affected by products of the main explosive eruptions of Somma-Vesuvius. The volcanic area, still active, and its surrounding territories has been inhabited since the Prehistoric time and many civilisations are documented by several archaeological findings. It has pointed out the role played by the negative effects of main explosive eruptions as cause of landscape alterations with very likely consequent modifications of local geo-environmental features from which depend the human activities, especially in Prehistorical time. The areas close to the volcano have had the greatest modifications or alterations of the topographic surface, whereas the distal ones have undergone only little modifications. This is probably also reflected on the time of resumption of the anthropic activities after the destruction caused by the eruption. In the archaeological sites nearer the volcano, in fact, the time of resumption is very long (centuries or thousand years), whereas it is shorter for the distal sites (up to 70 Km). The fact, although seems to be obvious, documents that the time of resumption depends on the time of restoration of the georesources (environmental hysteresis). In such highly vulnerable territory the ancient civilisations were strongly dependent from the local georesources, so that their activities and developments were connected to it. The present study is based on a re-interpretation of detailed geomorphological and stratigraphic data survey carried out in the area surrounding important archaeological sites. From data analysis emerges that the environmental hysteresis is related to the importance of the eruption (Plinian or no-Plinian), to the distance of the vent and to the cultural level of civilisation (as dependent from local georesources). As a result of that research comes out that since the Neolithic/Bronze Age the populations in the Vesuvian area has experimented a destiny of destructions and re-occupations: in fact, in many archaeological places has been found a complex stratigraphic succession made by alternations of anthropic occupation levels (archaeological strata) and catastrophic events as volcanic eruption products. These data help to think about the man/environment interactions in an area characterised by very strong and active volcanic risk with high frequency of destruction and restoration of georesources.