Submarine stratigraphy of the eastern Bay of Naples: new seismo-stratigraphic data and implications for the Somma-Vesuvius and Campi Flegrei volcanic activity

The submarine stratigraphy of the eastern Bay of Naples is studied through seismostratigraphic data correlated with borehole data. Multichannel seismic profiles are interpreted in order to reconstruct the stratigraphic relationships between the Quaternary marine seismic units and the volcanic acoustic substratum. Seven seismic units are recognized based on the geological interpretation of seismic profiles and using seismo-stratigraphic criteria. The top of the lowest seismic unit was correlated with the Campanian Ignimbrite (Southern Campania Volcanic Zone). The stratigraphic setting of the eastern Bay of Naples is characterized by NE-SW trending seismic structures, probably corresponding with tuff rings. These tuff rings can be compared with the Porto Miseno, the Archiaverno and Averno, and the Astroni tuff rings (Campi Flegrei). Offshore, the Somma-Vesuvius a seismic unit was interpreted as the fallout deposits representing the base of the AD 79 eruption. However, since a branch of the isopach of 5 m of the "Pomici di Avellino" pyroclastic deposits is very close to the Tyrrhenian coastline and near our GRNA01 and GRNA03 seismic profiles, we cannot exclude that the seismic unit could be also correlated with the deposits of this eruption.