Bradyseismic crises and ongoing processes at Campi Flegrei caldera, Naples? Update from combined monitoring of gas emissions and geophysical parameters.

The 12-km wide Campi Flegrei (Phlegrean Fields) caldera, bordering Naples, is one ‘supersite volcano’ in the heart of continental Europe, currently hosting 1.5 million of people. Campi Flegrei erupted 300 km3 of dense trachytic magma 35 ky ago (Campanian Ignimbrite) - equivalent to as much as 60 Pinatubo-type eruptions - and again ~50 km3 12 ky ago (Napolitean Yellow Tuff). Smaller central eruptions succeeded afterwards, the last of which in 1538. Managing eruptive hazards at Campi Flegrei is therefore one greatest challenge of civil defense in Europe. Over the last 2 ky at least, the caldera floor has shown impressive ground level variations associated with seismicity (‘bradyseism’) and intense gas emissions. Since the mid-20th century, successive seismogenic epidodes of ground uplift (~4m cumulated) have affected the caldera, suggesting a multi-step ongoing process. In his talk, Giovanni Chiodini (responsible of INGV fluid monitoring) will present an up-to-date assessment of this process, based on several decades of gas measurements and geophysical monitoring of Campi Flegrei volcanic complex.