We present the results of a detailed bathymetric survey of Pozzuoli Bay (Gulf of Naples, Italy). This shallow marine area, along with the Campi Flegrei inland, is a highly active volcanic district in the coastal zone of SW Italy. The area has been active since at least 78 ka B.P., and is structurally dominated by a caldera collapse (∼8 km in diameter) associated with the eruption of the Neapolitan Yellow Tuff (NYT), a 30–50 km³ dense rock equivalent (DRE) ignimbrite dated ∼15 ka B.P. The main cartographic product consists of a 1:10,000 scale morpho-bathymetric map of Pozzuoli Bay, derived from 1 m cell-size, colour hill-shaded, digital terrain model of the seafloor. Multibeam bathymetry data reveal the precise extent of Roman underwater archaeological remains located in the N–NW infralittoral zone of the Bay. Morphometric analysis allowed for the development of thematic representations, including slope and aspect maps. A complete data set of active fluid vents seafloor locations were also recorded during the survey and reported in the final map. The multibeam bathymetric survey illustrated in this study provides an unprecedentedly detailed image of the seafloor morphology of Pozzuoli Bay and represents a contribution to the understanding of the dynamic evolution of the Campi Flegrei caldera, a high-risk volcanic area densely populated by almost one million people.

This paper presents a comprehensive geological and geotechnical study of the whole area affected by liquefaction following the 2012 Emilia earthquakes, including all the available information from the field reconnaissance surveys, in situ tests, and laboratory analyses. The compilation was performed at 120 liquefied sites to verify and validate the reliability of liquefaction charts in alluvial sediments, and to assess liquefaction induced by the 2012 seismic sequence in the Emilia plain. The results reveal a wide range of grain sizes (from clean sands to sandy silts) and compositional characteristics (quartz-rich to litharenitic) in the 2012 ejecta, and show a strong relationship between the liquefaction and stratigraphic architecture of the subsurface. The availability of in situ tests at the liquefied sites makes it possible to verify and validate the reliability of the liquefaction charts in alluvial sediments with respect to the real observations. For the analyzed Emilia case studies, the use of non-liquefiable crust provides better estimations of the liquefaction manifestations when coupled with the thickness of the liquefiable layer rather than with the liquefaction potential index. Altogether, this work makes available to the international scientific community a consistent liquefaction database for in-depth earthquake studies.