The Bay of Naples (southern Italy): Constraints on the volcanic structures inferred from a dense seismic survey

The bays of Naples and Pozzuoli host volcanic areas that have been active within recent history. In addition, the vicinities areas around the Vesuvius volcano and the Campi Flegrei caldera are extremely densely inhabited. More recently, the Serapis active seismic survey covered the entire Bay of Naples, with particular attention to Pozzuoli Bay. The processed Serapis P wave travel time collection, extended with a previously acquired data set, has allowed the computation of the most comprehensive three-dimensional P wave velocity distribution for the Bay of Naples, which includes a small-scale high-resolution model of the Campi Flegrei caldera. The joint interpretation of the velocity distribution together with both the available gravity measurements and models and the geothermal drilling information has allowed us to locate and map lithological units at depths. We propose a model of the Campi Flegrei caldera in relation to the underlying Mesozoic limestone unit.