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Comprendere il comportamento, l'evoluzione e le caratteristiche del mare è una questione essenziale per affrontare alcune grandi sfide attuali in materia di ambiente: il cambiamento climatico, il ciclo del carbonio, l'acidificazione degli oceani, le variazioni della circolazione marina e i loro effetti, ecc. Per questo, il numero di studi sul mare è in aumento da alcuni anni a questa parte. La temperatura del sistema-mare è esplicitamente menzionata nell'allegato III della Marine Strategy Framework Directive (2008) come uno dei parametri che richiedono maggiore attenzione. Le misurazioni significative e coerenti della temperatura dell'acqua di mare sono essenziali per comprendere la sua influenza in quasi tutti i processi marini, nonché per comprendere i meccanismi di scambio di calore tra il mare e l'atmosfera.

A new high-resolution pollen record, spanning the last five millennia, is presented from the Gulf of Gaeta (Tyrrhenian Sea, central Italy), with the aim of verifying if any vegetation change occurred in the central Mediterranean region in relation to specific well-known global and/or regional climate events, including the 4.2 ka event, the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA), and to detect possible vegetation changes related to still under-investigated climate signals, for example the so-called “Bond 2” cold event around 2.8 ka BP. The vegetation dynamics of the Gaeta record shows a recurrent pattern of forest increase and decline punctuating the mid- and late Holocene. When the timing of these patterns is compared with the climate proxy data available from the same core (planktonic foraminifera assemblages and oxygen stable isotope record) and with the NAO (North Atlantic Oscillation) index, it clearly appears that the main driver for the forest fluctuations is climate, which may even overshadow the effects of human activity. We have found a clear correspondence between phases with negative NAO index and forest declines. In particular, around 4200 cal BP, a drop in AP (Arboreal Pollen) confirms the clearance recorded in many sites in Italy south of 43°N. Around 2800 cal BP, a vegetation change towards open conditions is found at a time when the NAO index clearly shows negative values. Between 800 and 1000 AD, a remarkable forest decline, coeval with a decrease in the frequencies of both Castanea and Olea, matches a shift in the oxygen isotope record towards positive values, indicating cooler temperatures, and a negative NAO. Between 1400–1850 AD, in the time period chronologically corresponding to the LIA (Little Ice Age), the Gaeta record shows a clear decline of the forest cover, particularly evident after 1550 AD, once again in correspondence with negative NAO index. © 2017 Elsevier Ltd

During the past decades a number of sequence stratigraphy studies illustrated how, during Quaternary, interaction between sea level changes and sediment supply controlled the depositional evolution along continental margins, giving a cyclic signature to the sedimentary infilling. However, as both deposition and erosion are processes ultimately controlled by balance between environmental energy and sedimentary influx, also the oceanographic regime takes part in controlling the sedimentary growth along the continental margin. This is exactly what occurs on physiographic settings as islands offshore areas, where bottom currents can be very energetic. In the western Sicily offshore, southwards of Egadi Islands, the sea floor is characterized by depositional and erosional features formed under a variety of sedimentary processes and offers opportunity to investigate as sea level change and oceanographic regime combine each other to control depositional evolution. In this area, located along the clockwise flow of the Levantine Intermediate Water around the western Sicily margin, the sea floor morphology is very irregular as consequence of isolated reliefs and narrow submarine valleys, such as the Marettimo Valley which separates Favignana and Marettimo islands. We analysed and interpreted a grid of high-resolution (1 kJ Sparker) seismic reflection profiles integrated with multibeam bathy-morphologic data of selected areas; a 270 cm long gravity core has been also collected for sedimentology and biostratigraphy. The sedimentary succession accommodated along the eastern flank of the Marettimo Valley shows two different seismic units: unit A displays reflection-free seismic facies and thin, low- amplitude, inclined reflectors with downlap terminations onto the lower boundary, and erosional truncation at the upper boundary; these seismic facies are referable to oblique-tangential clinoforms and show a wedge-shaped external geometry. Unit B shows continuous, parallel, slightly concave reflectors and, towards the central sector of the Valley, continuous, sub-horizontal reflectors that form a deposit having a very broad low-mounded geometry; lateral transition in between concave and sub-horizontal reflectors is characterized by channelized erosional truncations. The two seismic units can be interpreted as the sedimentary response of different depositional processes: unit A accumulated by progradation of shallow-water deposits during eustatic forced-regression; unit B is referable to contourite drifts deposited by bottom currents through the Marettimo Valley. This unusual interbedding of very shallow water contouritic and shelf margin deposits derives from enhanced sedimentary dynamics during sea-level fall and lowstand stages when, as consequence of decreased water depth of the Marettimo Valley, bottom currents accelerated scouring channelized erosional surfaces; in the same time, deposition of forced regression across the shelf margin buried contourite drifts.

An integrated marine geophysics and satellite remote sensing study of Naples Bay (Italy) has been carried out to evaluate the presence, magnitude, areal extent and activity of the Naples Active Deformation Line (NADEL), a structural bend affecting the post Last Glacial Maximum (LGM) sedimentary sequences. Sparker high-resolution mono-channel profiles and multibeam swath bathymetric data were acquired during the SAFE-2014 research cruise, carried out on board of the Urania R/V of CNR on August 2014. The marine geophysical study was integrated with the ground deformation field of the emerged sectors of the study area (Sorrento Peninsula and Campi Flegrei), derived by Synthetic Aperture Radar interferometry (InSAR) data, referred to the 1993-2000 and 2003-2010 time periods. The InSAR data obtained from the ERS, RADARSAT and ENVISAT images were processed with the method of Permanent Scatterers (PS). Marine geophysical data provide evidence of morphological and stratigraphic features extending for about 18 km along a N130E strike. The NADEL deformation bend divides a NE offshore area, characterized by a flat morphology (slope< 1°, on average) from a SW sector, where the slope at >180 m below the sea level is, on average, 1.5°). In the area located SW of NADEL, the slopes are morphologically characterized by the presence of the uppermost active branches of the Magnaghi canyon, which are bounded upward by the presence of the NADEL pattern. Thus, we suppose that the emplacement of the Magnaghi branches and NADEL are linked. InSAR data show that a similar deformation pattern can be detected also inland, in the distal sectors located NW and SE from the NADEL edges. The NADEL segments also affect the distal SW sector of the Campi Flegrei active caldera and the carbonate units cropping out in the Sorrento Peninsula, thus extending in length for more than 40 km.

We present a high-resolution paleoclimatic reconstruction of the last four millennia from a shallow water marine record recovered in the central Tyrrhenian Sea (Gulf of Gaeta) based on planktonic foraminifera and pollen records combined with oxygen stable isotope, tephrostratigraphic and magnetostratigraphic analysis. Paleoclimatic events have been recognised and discussed within the following time in intervals: Eneolithic (base of the core- ca. 2410 BC), Early Bronze Age (ca. 2410 BC - ca. 1900 BC), Middle Bronze Age - Iron Age (ca. 1900 BC - ca. 500 BC), Roman Period (ca. 500 BC - ca. 550 AD), Dark Age (ca. 550 AD - ca. 860 AD), Medieval Climate Anomaly (ca. 860 AD - ca. 1250 AD), Little Ice Age (ca. 1250 AD - ca. 1850 AD), Industrial Period (ca. 1850 AD - ca. 1950 AD), Modern Warm Period (ca. 1950 AD - present day). Within these time intervals, the proxy records document short-term climate oscillations well correlated with other records from Mediterranean marine areas (Alboran Sea, Gulf of Taranto, Adriatic Sea, and Ionian Sea). The long term trend in oxygen isotopic record obtained from the planktonic foraminiferal species Globigerinoides ruber (?18OG.ruber) has an antithetic correlation with the North Atlantic Oscillation (NAO) suggesting a strong northern hemisphere influence on the climate variability of the central Mediterranean region. The long term trend and amplitude oscillations of the ?18OG.ruber signal, the onset of main planktonic foraminiferal turnover from carnivorous to herbivorous-opportunistic species, and the consistent fluctuations of the pollen records document an important modification in climate system from the onset of the Roman Period up to the present-day. In addition, from ca. 500 AD upwards, the planktonic foraminiferal ?18O data, from marine records, shows a synchronous progressive long-term shift to more positive values superimposed to short-term oscillation, suggesting a Mediterranean secular scale signature in isotopic composition. From Maunder event to present day there is a progressive inversion in ?18O composition, suggesting the onset of the modern warm climate condition.

The 5 km wide Banco della Montagna (BdM) morphological high is located on the seafloor of Naples Bay (Tyrrhenian Sea, Italy) and is characterized by a hummocky surface. Oceanographic surveys revealed active fluid vents at BdM. High-resolution mono-channel seismic and multibeam bathymetry allow us to define the detailed morphology and the inner geometry of BdM, which consists of a complex set of dome-like structures (pagodas) affecting the present-day seabed. We suggest that a gas-water-sand sediment mixture upraises from a gas saturated layer pushing up the overlying marine deposits and forming mounds, folds, and faults. According to a thin-plate elastic model, we estimate the fluid (gas) pressure Pdef required to form BdM and obtain Pdef = 0.3 Pa, a value consistent with that for doming processes in gas-hydrate settings. At BdM, the pressure ?P required to break the seabed is in the order of 2-3 MPa, while the gas column height is about 240 m.

Large calderas are among the Earth's major volcanic features. They are associated with large magma reservoirs and elevated geothermal gradients. Caldera-forming eruptions result from the withdrawal and collapse of the magma chambers and produce large-volume pyroclastic deposits and later-stage deformation related to post-caldera resurgence and volcanism. Unrest episodes are not always followed by an eruption; however, every eruption is preceded by unrest. The Campi Flegrei caldera (CFc), located along the eastern Tyrrhenian coastline in southern Italy, is close to the densely populated area of Naples. It is one of the most dangerous volcanoes on Earth and represents a key example of an active, resurgent caldera. It has been traditionally interpreted as a nested caldera formed by collapses during the 100–200 km3 Campanian Ignimbrite (CI) eruption at ∼39 ka and the 40 km3 eruption of the Neapolitan Yellow Tuff (NYT) at ∼15 ka. Recent studies have suggested that the CI may instead have been fed by a fissure eruption from the Campanian Plain, north of Campi Flegrei. A MagellanPlus workshop was held in Naples, Italy, on 25–28 February 2017 to explore the potential of the CFc as target for an amphibious drilling project within the International Ocean Discovery Program (IODP) and the International Continental Drilling Program (ICDP). It was agreed that Campi Flegrei is an ideal site to investigate the mechanisms of caldera formation and associated post-caldera dynamics and to analyze the still poorly understood interplay between hydrothermal and magmatic processes. A coordinated onshore–offshore drilling strategy has been developed to reconstruct the structure and evolution of Campi Flegrei and to investigate volcanic precursors by examining (a) the succession of volcanic and hydrothermal products and related processes, (b) the inner structure of the caldera resurgence, (c) the physical, chemical, and biological characteristics of the hydrothermal system and offshore sediments, and (d) the geological expression of the phreatic and hydromagmatic eruptions, hydrothermal degassing, sedimentary structures, and other records of these phenomena. The deployment of a multiparametric in situ monitoring system at depth will enable near-real-time tracking of changes in the magma reservoir and hydrothermal system., This research has been supported by the European Consortium for Ocean Research Drilling (ECORD) through the ECORD/ICDP MagellanPlus Workshop Series Programme (grant no. 2017.2376/4/AF).

This chapter illustrates the marine record of a spectrum of volcanic, hydrothermal, and sedimentary features that characterize the Latest Pleistocene–Holocene evolution of the Naples Bay offshore Campi Flegrei and Somma–Vesuvius. The work is based on review of previous literature integrated with interpretation of new high-resolution marine Digital Terrain Models (DTMs) derived from swath bathymetry surveys and high-resolution reflection seismic profiles calibrated with marine gravity core data. Seismic profiles from Pozzuoli Bay provide detailed images of the ring fault system and resurgent dome associated with the evolution of the Neapolitan Yellow Tuff (NYT) collapse caldera and document a series of uplift episodes associated with volcanic unrest as documented on land throughout the Holocene, with a notable subsidence phase occurring between ∼ 2.5 ka BP and 1538 CE (Monte Nuovo eruption). Offshore seismic images also revealed the occurrence of ascending hydrothermal fluids and volcanic/subvolcanic intrusions along the ring fault zone of the NYT caldera. Seismic data acquired along the SW submerged slope of Somma–Vesuvius display evidence of gravitational instability, associated with slump folding and faulting, of sand waves originated by pyroclastic flows that entered the seawater after destroying the Roman city of Herculaneum during the 79 CE eruption of Vesuvius. Between the Somma–Vesuvius and Pozzuoli Bay, seismic profiles calibrated with gravity core data revealed the occurrence of a hummocky seafloor region, known as Banco della Montagna (i.e., the Montagna bank). This volcanic bank was shaped by the dragging and rising up of volcaniclastic diapirs (mostly unconsolidated pumice) because of pore fluid overpressure at depth and associated active fluid venting at the seafloor.

An integrated stratigraphic analysis was carried out on the TEA C6 gravity core raised from the Amendolara basin in the Gulf of Taranto. The 4.5 m long succession was investigated by means of sedimentology and textural analysis, petrophysics, micropaleontology and geochemistry with a refined dating framework provided by oxygen isotope, tephrochronology and 14C AMS ages. Textural and micropaleontological data were analysed by means of Compositional data analysis. The results pointed to a deep marine record with no or little disturbance and they aimed to contribute to the reconstruction of the palaeoceanographical and paleoclimatic changes occurred in this sector of the Central Mediterranean during the last 15 ka BP. In particular, data obtained along the sapropelitic interval corresponding to the Sapropel S1 deposition (9.6-7.5 ka BP), offered a detailed insight on the conditions that characterised the study area during this phase. The deposit was sampled with a continuous step of 1 cm-slides of sediment and this allowed to have resolution even in the order of 50 years. During the early Holocene, before the onset of Sapropel deposition, foraminifera show evidence of several centuries characterised by persistence of winter mixing and likely summer eutrophication. The weakening of winter mixing is simultaneous with a change in bottom conditions, leading to the dominance of oxygen resistant species and then to the establishment of anoxic conditions. During this phase, truly onoxic conditions alternate with periods of partial recovery of benthic faunas, the longest of which correspond to the Sapropel S1 interruption. This moment is time fixed by the occurrence of a tephra layer interbedded within the marine deposit. The end of the Sapropel S1 phase coincides with the re-establishment of winter mixing, although eutrophication persists during a transition interval 400 years long. Dynamics and duration of Sapropel S1 in the Gulf of Taranto show similarities with those of the Adriatic Sea. Sea Surface Temperatures (SST) recontructions obtained from planktonic foraminifera by means of CoDaMAT indicate during the stadial GS1 (Younger Dryas) summer and winter SST about 12°C and 7°C lower than present, respectively, and Holocene SST fluctuations in the range of 2°C. According to the results, TEA C6 core might represent a reference archive for the Gulf of Taranto in terms of response of the sedimentary environment to palaeoceanographical and paleoclimatic changes from the late glacial to the late Holocene.

We report evidences of active seabed doming and gas discharge few kilometers offshore from the Naples harbor (Italy). Pockmarks, mounds and craters characterize the seabed. These morphologies represent the top of shallow crustal structures including pagodas, faults and folds affecting the present-day seabed. They record upraise, pressurization and release of He and CO2 from mantle melts and decarbonation reactions of crustal rocks. These gases are likely similar to those that feed the hydrothermal systems of the Ischia, Campi Flegrei and Somma-Vesuvius active volcanoes, suggesting the occurrence of a mantle source variously mixed to crustal fluids beneath the Gulf of Naples. The seafloor swelling and breaching by gas upraising and pressurization processes require overpressures in the order of 2–3 MPa. Seabed doming, faulting and gas discharge are manifestations of non-volcanic unrests potentially preluding submarine eruptions and/or hydrothermal explosions.