FTI.1 | The Campi Flegrei caldera volcanism and the unrest phenomena
The Campi Flegrei is an active volcanic field resulting mainly by two large caldera forming events. The large eruption of the Campanian Ignimbrite (40 ka), known as the major event of the Mediterranean area over the last 200.000 years, generated the Campi Flegrei caldera and was followed by an intense volcanic activity, culminated in a second large eruption dates back 15 ka wich emplaced the Neapolitan Yellow Tuff (NYT). Following the NYT eruption, activity within the caldera generated at least 70 volcanic eruptions, concentrated mainly in discrete periods alternating with periods of quiescence of variable length. The eruption of Monte Nuovo in 1538 A.D. was the last eruption of the caldera. The volcanic activity of Campi Flegrei was characterized mainly by explosive eruptions of low and medium magnitude and less frequent effusive events. The location of eruptive vents has changed over time, and simultaneous eruptions in the two different sectors of the caldera also occurred from the Solfatara and Averno volcanoes.
The caldera underwent ground deformation that resulted in a total uplift of more than 100 m in its central part during the last 15,000 years. Even over several decades before the Monte Nuovo eruption, ground uplift had reached several meters. Recently, slow ground movement (bradyseism) has occurred in the area, with two major bradyseismic crises (1970-72 and 1982-84) accompanied by hundreds of earthquakes and 3.5 m of ground uplift, leading toFtohtoedpi aSrtteifaalneovBarcanucaation of the town of Pozzuoli. Different episodes of ‘micro-uplift’ with maximum displacement of a few tens of cm occurred in the last 30 years and are currently underway.
The visit of particular volcanic structures will lead the participants through an itinerary in the Campi Flegrei devoted to illustrate and discuss the volcano history of the Campi Flegrei, the ground deformation dynamics in a resurgent caldera, and the possible future scenario and risk related to an eventual resumption of the eruptive activity at Campi Flegrei. Stops to the active fumarolic field of the Solfatara area, as well as to the Pozzuoli harbour and Serapeo Roman archaeological ruins, will allow discussing in depth volcanic hazards related to unrest episodes and the relationships between unrest episodes and eruptions. There will also be the opportunity to assess from inside the volcano the physical relationship between volcanic and human activities and discuss about the volcanic risk perception by residents including a large part of the city of Napoli.