Stratigraphic and structural setting of the Ischia volcanic complex (Naples Bay, Southern Italy) revealed by submarine seismic reflection data

摘要

High-resolution seismic reflection profiles(Sparker Multitip) offshore southern Ischia Island (Naples Bay) are presented, together with a geological interpretation of their volcanic, structural and sedimentary features.udIn this frame, new seismo-stratigraphic evidences on buriedudvolcanic structures and overlying Quaternary deposits ofudthe southeastern offshore of the Ischia Island are discussedudto highlight their implications on the marine geophysicsudand volcanology. The Ischia Bank is a large and flat relicudvolcanic edifice with steep slopes, merging on the continental shelf. The age of this monogenic volcano is unknown, lacking a direct datation of its basement. It represents the eruptive center of the pyroclastic fall cropping out onshore in the eastern sectors of the island, ranging in age from 8 to 6 ky BP. In the eastern Ischia offshore relic volcanic edifices, mostly formed by hialoclastites, have been investigated through high-resolution seismics. They represent remnants of hydro-magmatic volcanic vents and suggest a subaqueous emplacement. Regional seismic sections in the southeastern Ischia offshore, across buried volcanic structures, are finally presented and discussed.