New seismo-stratigraphic and marine magnetic data of the Gulf of Pozzuoli (Naples Bay, Tyrrhenian Sea, Italy): inferences for the tectonic and magmatic events of the Phlegrean Fields volcanic complex (Campania)

Abstract

A detailed reconstruction of the stratigraphic and tectonic setting of the Gulf of Pozzuoli (Naples Bay) is provided on the basis of newly acquired single channel seismic profiles coupled with already recorded marine magnetics gathering the volcanic nature of some seismic units. Inferences for the tectonic and magmatic setting of the Phlegrean Fields volcanic complex, a volcanic district surrounding the western part of the Gulf of Naples, where volcanism has been active since at least 50 ka, are also discussed. The Gulf of Pozzuoli represents the submerged border of the Phlegrean caldera, resulting from the volcano-tectonic collapse induced from the pyroclastic flow deposits of the Campanian Ignimbrite (35 ka). Several morpho-depositional units have been identified, i.e., the inner continental shelf, the central basin, the submerged volcanic banks and the outer continental shelf. The stratigraphic relationships between the Quaternary volcanic units related to the offshore caldera border and the overlying deposits of the Late Quaternary depositional sequence in the Gulf of Pozzuoli have been highlighted. Fourteen main seismic units, both volcanic and sedimentary, tectonically controlled due to contemporaneous folding and normal faulting have been revealed by geological interpretation. Volcanic dykes, characterized by acoustically transparent sub-vertical bodies, locally bounded by normal faults, testify to the magma uprising in correspondence with extensional structures. A large field of tuff cones interlayered with marine deposits off the island of Nisida, on the western rim of the gulf, is related to the emplacement of the Neapolitan Yellow Tuff deposits. A thick volcanic unit, exposed over a large area off the Capo Miseno volcanic edifice is connected with the Bacoli-Isola Pennata-Capo Miseno yellow tuffs, cropping out in the northern Phlegrean Fields.

Submarine Stratigraphy of the Eastern Bay of Naples: New Seismo-Stratigraphic Data and Implications for the Somma-Vesuvius and Campi Flegrei Volcanic Activity

“…This paper interprets the submarine stratigraphy of the Gulf of Naples, focusing on the eastern Bay of Naples, based on multichannel seismic data. These data highlight the stratigraphic relationships between the Quaternary marine and volcanic deposits, with thick seismic units identified as the Campanian Ignimbrite (CI seismic unit) [8][9][10][11][12][13][14][15] and the Neapolitan Yellow Tuff (NYT seismic unit) [16][17][18][19][20][21].…”

Integrated Morpho-Bathymetric, Seismic-Stratigraphic, and Sedimentological Data on the Dohrn Canyon (Naples Bay, Southern Tyrrhenian Sea): Relationships with Volcanism and Tectonics

“…The relative bathymetric data were acquired between 1997 and 2017, using multibeam systems with an average vertical resolution of <0.25% water depth and a position accuracy of <10 m. The survey data were successively merged with a Digital Terrain Model (DTM) created from topographic maps of the Naples Bay onshore coastal area and islands, to produce a Digital Elevation Model (DEM) based on a homogeneous grid with cell-spacing of 20 m (Figure 5) [78]. Major morphological elements of the Naples Bay include: (1) the Dohrn-Magnaghi canyon system, carving the continental slope at water depths between −250 m and −1100 m [77][78][79][80][136][137][138][139]; (2) the continental slope system of the Ischia island and related submarine canyons [74]; (3) the onshore and offshore volcanoes of the Campi Flegrei (Pentapalummo, Nisida, and Miseno banks) [18,21,28,[30][31][32][33]; (4) the rough sea bottom area of the outer shelf of the city of Naples (Banco della Montagna) [78,81,[137][138][139]; (5) the sediment wave field of the inner continental shelf off the Vesuvius [34,35,78,81,[137][138][139][140].…”

“…the continental slope at water depths between −250 m and −1100 m [77][78][79][80][136][137][138][139]; (2) the continental slope system of the Ischia island and related submarine canyons [74]; (3) the onshore and offshore volcanoes of the Campi Flegrei (Pentapalummo, Nisida, and Miseno banks) [18,21,28,[30][31][32][33];…”

“…The area has been interpreted as the result of two large caldera collapses related to the eruptions of the Campanian Ignimbrite (~39 ka) [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] and the Neapolitan Yellow Tuff (NYT, 15 ka). The southern submerged margin of the Campi Flegrei caldera is represented by the Pozzuoli Bay [28,[30][31][32][33].…”

Integrated on‐land‐offshore stratigraphy of the Campi Flegrei caldera: New insights into the volcano‐tectonic evolution in the last 15 kyr

“…With this scope, several studies have assessed the stratigraphy of the offshore caldera basin‐fill using seismic reflection datasets of different vintages and resolution (Aiello et al, 2012, 2016; Fusi et al, 1991; Milia, 1998; Milia et al, 2000; Natale et al, 2020; Pescatore et al, 1984; Sacchi et al, 2014, 2019; Steinmann et al, 2016, 2018). In this work, we benefit from a blend of high‐ and very‐high‐resolution seismic profiles, and provide a detailed stratigraphic framework for the submerged part of the caldera and integrate the marine record of the Pozzuoli Gulf with both the La Starza marine succession on‐land and the whole continental tephrostratigraphic records of the caldera.…”