Radon in active volcanic areas of Southern Italy

The radiogenic gas radon is considered a valid precursor of events like erupt-ions and earthquakes. We are monitoring the variations in time of this gas in soils and in waters of many active volcanic areas of Southern Italy. The greatest differences in Rn content of the investigated Volcanic areas are: Ischia and Campi Flegrei have more Rn than Vesuvio and Vulcano, both in soils and in waters. The thermalized waters of Ischia are enriched in Rn 15 times with respect to soils, while in the other areas soils and underground waters have comparable Rn contents.