The geothermal exploration of Campanian volcanoes: Historical review and future development

Since Roman time, the heat produced by Neapolitan volcanoes was an appeal for people living in and outside the area, for the fruition of the famous thermal baths. This very large area, which spans from Campi Flegrei and Ischia calderas to Somma-Vesuvius volcano, is characterized by high temperature at shallow depth and intense heat flow, and is yet utilized for the bathing and spa treatment industry, while only in the middle of the 20th century a tentative of geothermal exploitation for energy production was performed. Pioneering researches of geothermal resource were carried out in Campanian region since 1930, until 1985, during which a large amount of geological data were collected. In this paper, we make for the first time a review of the history of geothermal explorations in the active Campanian volcanic area. By the analysis of a great amount of literature data and technical reports we reconstruct the chronology and the main information of the drillings performed since 1930 by the SAFEN Company and successively in the framework of the ENEL-AGIP Joint Venture for geothermal exploration. The available data are utilized to correlate the temperatures measured within the deeper wells with the possible sources of geothermal heat in the shallow crust, down to about 8–10 km of depth. Finally, we assess the geothermal potential of the hottest areas, Ischia Island and Campi Flegrei, which have shown the best data and favorable physical conditions for a reliable, and cost-effective, exploitation for thermal and electric purposes.