Italy's Supervolcano May Erupt Soon

On 29 Sep 1538, an eruption began which built the cone Mte. Nuovo (123 m) during one week. A modern summary of the eruption has been given by Di Vito et al. (1987), also containing citations from contemporary reports.

The eruption was preceded by a period of uplift in the area that ended a long (at least 1400 years) period of subsidence. Although the beginning of this uplift is not precisely known, the emergence of new land from places formerly occupied by the sea was first noted by residents of Pozzuoli in 1502. This uplift was, from the early 1530's, accompanied by unusual seismicity that reached a first climax in the spring of 1534. Still more earthquakes were felt in the area during the following 4 years, dramatically increasing during Sep 1538. On the 28th, about 20 tremors were felt between daybreak and nightfall.