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This paper describes the results of the activities performed during the project PONa3_00363 I-AMICA (High Technology Infrastructure for Climate and Environment Monitoring; www.i-amica.it), as part of the activities of Development Objective 4.4 (Processes of the biosphere-hydrosphere interface and features of coastal ecosystems). Through the strengthening of scientific-technological infrastructure and equipment, I-AMICA was planned to increase the observational capacity of the monitoring of marine coastal ecosystems, particularly vulnerable in the sensitive Mediterranean area and strictly connected to the natural and anthropic continental system. For this reason research activities were mainly focused on the neritic environment adjacent to the shelf area of the Volturno River mouth (Gulf of Gaeta - central part of the Tyrrhenian Sea). Advanced knowledge on the dynamics in time of marine coastal ecosystems, in relation to the physical, chemical and biological processes that characterize their habitat, were acquired while new methods of integrated monitoring, in relation to the specific characteristics of the study area, were tested. Particular attention was given to the identification of bio-indicators in water column and sediment at sea floor. The monitoring was also integrated by studies on the shoreline changes, seismic stratigraphy of deltaic deposits and by sedimentology and morpho-bathymetry of the seabed., Vengono presentati i risultati dell’attività di monitoraggio svolta nel corso del progetto PONa3_00363 I-AMICA (Infrastruttura di Alta tecnologia per il Monitoraggio Integrato Climatico-Ambientale; www.i-amica.it/i-amica/), nell’ambito delle attività relative all’Obiettivo Realizzativo 4.4 (Processi di interfaccia biosfera-idrosfera e funzionalità degli ecosistemi costieri). L’attività, che ha avuto come scopo l’acquisizione di conoscenze avanzate sulle dinamiche e/o variazioni nel tempo degli ecosistemi marino-costieri in relazione ai processi fisici, chimici e biologici che caratterizzano il loro habitat, si è sviluppata attraverso la sperimentazione di nuove metodologie di monitoraggio in relazione alle specifiche caratteristiche dell’area marino-costiera prospiciente la foce del fiume Volturno (Golfo di Gaeta). In particolare, oltre che sulle tecniche di monitoraggio classiche, lo studio si è principalmente focalizzato sulla acquisizione ed interpretazione di dati ambientali sia in colonna d’acqua che nei sedimenti a fondo mare e sulla identificazione di specie e/o associazioni di specie significative (bio-indicatori) da un punto di vista ambientale ed indicative dello stato di salute del sistema costiero. Poiché il sistema costiero rappresenta una struttura naturale complessa e delicata, la cui evoluzione è il risultato di delicati equilibri fisici, chimici e biologici, fortemente condizionabili dagli interventi antropici, l’attività di monitoraggio è stata integrata da studi sulla variazione della linea di costa, da studi sismostratigrafici della piana deltizia, sedimentologici e morfo-batimetrici dei fondali.

In the recent years, Unmanned Surface Vehicles (USVs) have proved their usefulness in particular to collect data for marine research and environmental survey. The use of these controlled remotely platforms, without direct human control, have improved the capacity to image, and monitor the seabed and the costalmarine environment. Outfitted with different instruments (payload), the USVs are used for marine, river and lake activities, such as environmental monitoring, water quality sampling, hydrologic survey, target tracking and scientific survey [Bertram, 2008; Manley, 2008; Giordano et al., 2015]. Other fields of application include harbor surveillance, maritime search, rescue and natural disaster damage assessment [Steimle et al., 2009]. One of the first USV was ARTEMIS, designed in 1993 at MIT (Massachusetts Institute of Technology, Sea Grant Collage) [Manley, 1997] to collect bathymetric data and it was characterized by a propulsion system with two electric motors and a rudder servant-implemented. The USV was equipped by an automatic control of the heading and an autonomous navigation capacity through reference points (waypoints). Its small dimension (about 1.37m long) was the main shortcoming, limiting the endurance and the sea keeping. Following the development of ARTEMIS, to improve the transverse stability and to design more payload capacity and redundancy as regards the buoyancy, MIT adapted the catamaran shape for the hull and removed the rudder; the steering is based on a differential propeller revolution rate. After the MIT, several USVs were designed within many research projects. Among these, other USV were realized. The DELFIM, capable of working in close cooperation with an Autonomous Underwater Vehicles (AUV) [Pascoal et al., 2000] and the ROAZ, ROAZ II, that, set up for bathymetry survey, were designed to allow testing and validation of new developments in monitoring, coordinating multi-vehicle navigation, sampling and other research topics related to marine surface vehicles [Ferreira et al., 2006a, 2009]. Further developed concerned the SWORDFISH, MESSIN and SPRINGER vehicles. The SWORDFISH [Ferreira et al., 2006b, 2007] is a survey vehicle, with modular sensor payloads and a mobile gateway for air to underwater communication. The MESSIN [Majhor and Buch, 2006] is a catamaran dedicated to delivering sensors for oceanographic operations or hydrological mapping. The vehicle is suitable to operate in very shallow water, without destructive effects on the marine environment. The autonomous navigation system allows following the pre-programmed routes efficiently. The SPRINGER was developed in 2004 [Naeem et al., 2006; 2008] for tracking of pollutants, hydrographical surveys in rivers, water resources and coastal waters. As marine platform, SPRINGER was designed to be used also as a test-bed for intelligent navigation systems and for testing of new technologies for the sensors. Several developments in the modelling of twin hull USVs were presented also by the CNR-ISSIA (Italy) [Caccia et al., 2006] that within the SESAMO project designed the catamaran Charlie for sampling activity in the Antarctic Region [Caccia et al., 2006]. This technical report describes an innovative and integrated prototype system of Unmanned Surface Vehicles (USVs) for advanced environmental monitoring; the water platform’s is developed at the Coastal Marine Environmental Institute – National Research Council (Italy), within the Project: Integrated Systems and Technologies for Geophysical and Environmental Monitoring in coastal-marine areas (STIGEAC), in the framework of the National Operational Programs 2007-2013. The project concerns in the research of new technologies and the design of vehicles, for the surveys of the coastal marine environment, understood as a “multipurpose” laboratory for sea research with characteristics of modularity and portability. The goal involves not only the execution of scientific and technological research but also for the valorization of marine cultural heritage, for industrial activity and for emergency interventions related to environmental crises. Major innovations concern the design of a new architecture of the control system and/or to allow the cooperation between heterogeneous unmanned vehicles, the integration of distributed sensing techniques and real-time image processing capabilities [Marsella et al., 2015].

Remotely Piloted Aircraft Systems - RPAS [ICAO, 2011], usually called drones, are an emerging technology presenting a huge potential for innovative research in territory management. These systems will revolutionize most of the environmental studies (e.g. population ecology, vegetation dynamics, ecosystem processes, etc.) that are improved by remote sensing data, overcoming satellite-based data that provide not easy repeatable information and only at regional/global scale (from about 50-100 km up to 10.000 km). RPAS or Unmanned Aerial Systems (UAS1) history begun in 1916 (i.e. the Wright brothers HewittSperry Automatic airplane) and it has been mainly unfolded until today thanks to military applications [Colomina and Molina, 2014; Pappot and de Boer, 2015]. Nowadays, UAS based technology is rapidly developing in the industrial market and in civil applications for several kind of monitoring services (i.e. traffic monitoring, border surveillance, environmental monitoring, imaging and mapping, archaeology, search and rescue operations, etc.) [Valavanis and Vachtsevanos, 2015]. Moreover, the use of drones, in the global consumable market is continually growing due to the integration on Unmanned Aerial Vehicle (UAV) platforms of high performance processors, sensors and electronic devices with lower and lower power consumption. Mainly, light Remote Piloted Aircraft Systems (RPASs) are used in several application fields due to their low weight and low size.

The technical report describes the recent application of Electrical Resistivity (ERT) and Ground Penetrating Radar (GPR), for reconstructing buried structural geometries of a cultural heritage site in the city of Napoli, characterized by complex environmental and logistic conditions. The investigated site is the Carmine bell tower, located in the East seaside area of Naples (Italy), close to the neighboring magnificent church. The electromagnetic surveys were finalized to detect the foundation geometry of the high monumental bell tower resting on loose alluvial and pyroclastic soils. In fact, such non-invasive methods can assist the geotechnical engineers in the detection of foundation geometry when cultural heritage needs to be preserved and penetrating investigation tools (such as boreholes) must be avoided or, at least, their impact reduced to the minimum.

The technical report describes the application of non-invasive geophysical methods, Electrical Resistivity (ERT) and Ground Penetrating Radar (GPR), for reconstructing the buried subsoil geometries of a cultural heritage site in the city of Napoli, characterized by complex environmental conditions. The investigated site is the Fontanelle Cemetery, a cavity network made by chamber and pillars, one of the most fascinating hypogean sites excavated for the exploitation of the Neapolitan Yellow Tuff, whose origin may be traced back in the XVI century. The electromagnetic surveys were finalized to detect the buried subsoil geometry and the real height of the buried pillars.

A common problem of coastal aquifers is saltwater intrusion, induced by the flow of seawater into freshwater aquifers due to the groundwater development near the coast. Several factors affect the ingression of sea water. Among these, the most important are the coastal subsidence, the lowering of the sea level, coastal erosion and excessive pumping of groundwater. In fact, where the groundwater is pumped from coastal aquifers, the induced gradients may cause the migration of salt water from the sea to the well, making the freshwater unusable; being the fresh water less dense than salt water, it floats on top. According to the Integrated Coastal Zone Management (ICZM) of the European Commission, coastal areas are of great environmental, economic, social and cultural relevance. Therefore, the implementation of suitable monitoring and protection actions is fundamental for their preservation and for assuring the future use of this resource. Such actions have to be based on an ecosystem perspective for preserving coastal environment integrity and functioning and for planning sustainable resource management of both the marine and terrestrial components. Planning and management of natural resources through a dynamic process has to set, as its objective, the promotion of economic and social welfare of coastal zones. Unfortunately coastal plains are often contaminated by sea water intrusion, and the vulnerability to salinization is probably the most common and diffused problem in an aquifer. The boundary between salt water and fresh water is not distinct; the dispersion and transition zone, or salt-water interface are brackish with salt water and fresh water mixing. Under normal conditions fresh water flows from inland aquifers and recharge areas to coastal discharge areas to the sea. In general, groundwater flows from areas with higher groundwater levels (hydraulic head) to areas with lower groundwater levels. This natural movement of fresh water towards the sea prevents salt water from entering freshwater coastal aquifers (Barlow, 2003). Sea water intrusion in the water table can cause significant worsening in vegetation status. A likely related soil salinization would cause detrimental environmental and socioeconomic impacts. Hence, monitoring the sea water intrusion represents a priority for the safeguard of coastal areas. Identify changes in the freshwater-saltwater interface position can be a useful element for the rationalization of water resources and to guide the choice of use of these areas. Among the geophysical method applied for the location and movement of saltwater intrusion, best results were obtained by electrical methods (Al-Sayed and Al-Quady, 2007; Chitea et al., 2011). Many hydrological processes can be expected to provide significant contrasts in resistivity, consequently, Electrical Resistivity Tomography (ERT) has been adopted as a tool for new research within the hydrology field. Previous workers have demonstrated the ability of ERT to visualize hydrological structure within laboratory cores (Binley et al., 1996a, 1996b), monitor fluid or contaminant migration at the field scale (Daily et al., 1992, 1995; Schima et al., 1993), and to ascertain the efficiency of new contaminant remediation processes (Daily and Ramirez, 1995; LaBrecque et al., 1996). This paper outlines the results of a 3D ERT experiment obtained in the coastal alluvial plain of the Volturno river to assess changes in the freshwater-brine interface. The main aim was to investigate spatial and temporal variations of groundwater salinity. Acquisitions have been carried out in the months of May and October 2013 and in May 2014. This acquisition has allowed to obtain a monitoring 4D salt wedge in a "volume" specific subsurface.

Le zone di transizione marino-costiere, le aree alluvionali o vulcaniche sono generalmente caratterizzate dalla presenza di terreni sciolti e forti variazioni geometriche latero-verticali, che si ripercuotono sul campo di velocità del sottosuolo in questi casi estremamente variabile. La tomografia sismica multicanale a rifrazione è una tecnica di prospezione sismica che permette di definire un modello bi-dimensionale del sottosuolo, grazie l'individuazione delle anomalie di velocità di propagazione delle onde sismiche. Questa metodologia possiede un potere risolutivo nettamente superiore agli altri metodi convenzionali a rifrazione (es: Metodo Reciproco Generalizzato (GRM), metodo del tempo di ritardo (delay time), metodo del tempo intercetto), i quali si basano su un modello di sottosuolo costituito da strati regolari e con proprietà elastiche costanti, e che di conseguenza risultano inadeguati quando si è in presenza di forti variazioni laterali della velocità o inversioni di velocità con l'aumentare della profondità, cioè in presenza di situazioni geologicamente complesse. Il metodo sismico multicanale a rifrazione, grazie alla sua versatilità, è uno dei metodi geofisici più comunemente utilizzati per l'esplorazione del sottosuolo. Tale tecnica permette, infatti, di ricostruire in maniera dettagliata le morfologie sepolte e definire la presenza di eventuali discontinuità in sottosuolo (faglie, fratture). La tomografia sismica viene ampiamente adoperata a terra a scopi ingegneristici; invece in mare ha un'applicazione limitata, in particolare nelle zone costiere e di transizione come porti, lagune e baie. Recentemente, è stato dimostrato che le indagini sismiche a rifrazione in ambiente marino superficiale, possono fornire contributi importanti per la caratterizzazione degli strati del sottosuolo in termini di spessore e di velocità delle onde compressive VP (Whiteley&Stewart, 2008). La velocità delle onde P, infatti, è legata alla rigidità dei materiali e costituisce, quindi, un parametro importante per individuare il bedrock sismico ed i rapporti stratigrafici tra questo ed i sedimenti di copertura. La ricostruzione accurata del tetto della morfologia del bedrock sismico e quindi la valutazione della variazione degli spessori delle unità più superficiali è indispensabile nei progetti inerenti lo sviluppo di un'area portuale come ad esempio la costruzione di ponti o banchine e soprattutto nella stima degli interventi di dragaggio e ripascimento (MacGergor et al., 1994, Young Ho Cha et al., 2003). Al fine di dimensionare un intervento di dragaggio da eseguirsi nello specchio d'acqua del "Porticciolo della Tonnara" di Capo Granitola, a Campobello di Mazara (TP), l'Istituto per l'Ambiente Marino Costiero del CNR di Napoli ha eseguito un test di sismica marina multicanale a rifrazione. Sono stati realizzati 4 profili sismici, di cui tre seriati e paralleli alla costa ed incrociati da un quarto profilo, al fine di ottenere dati di tomografia sismica da elaborare mediante tecniche 2D e 3D. L'indagine ha interessato la fascia batimetrica compresa tra -1 e -3 metri e ha previsto il posizionamento di un cavo idrofonico d'acquisizione (bay-cable) direttamente sul fondale del porticciolo allo scopo di elaborare modelli di velocità bidimensionale delle onde P ed S.

L'interesse è rivolto ad un sistema di misurazione di parametri fisici (es.: vibrazioni, stress, variazioni di quota) in grado di superare le problematiche di posizionamento ed interferenza con altre emissioni elettromagnetiche che si manifestano nell'ambito di un vettore navale. Inoltre la rete di collegamento tra i diversi sensori deve essere in grado di sopportare elevati e persistenti stress sia di tipo meccanico che di tipo termico, ed avere infine una buona resistenza nei confronti di sostanze chimiche utilizzate e riscontrabili a bordo (sala macchine, stive, etc.).

SEISMO-STRATIGRAPHIC AND MARINE MAGNETIC DATA OF THE GULF OF POZZUOLI (NAPLES BAY, SOUTHERN TYRRHENIAN SEA): RELATIONSHIPS WITH THE GEOLOGY AND THE VOLCANOLOGY OF THE PHLEGREAN FIELDS VOLCANIC COMPLEX (CAMPANIA) G. Aiello (1), E. Marsella, V. Di Fiore (1) (1) IAMC-CNR, Sede di Napoli, Napoli, Italy 1. INTRODUCTION Seismo-stratigraphic and marine magnetic data of the Gulf of Pozzuoli are here presented on the basis of the geological interpretation of recently collected Sparker profiles (Aiello et al., 2012a; 2012b). The geology and the volcanology of the Phlegrean Fields volcanic complex and its adjacent offshore (Gulf of Pozzuoli) are here improved through a new stratigraphic setting delineated through seismic stratigraphy. Offshore stratigraphic units have not been recently discussed in detail in an active volcanic area as the Gulf of Pozzuoli, where active volcanism is suggested by bradyseismic movements and small earthquakes. According to many geological interpretations, this area represents the submerged border of the Phlegrean Fields caldera, located in correspondence to the Nisida, Miseno and Pentapalummo banks (Pescatore et al., 1984; Milia and Giordano, 2002; Aiello et al., 2005). Deep drilling of the Phlegrean caldera volcanic units onshore is now in course at the Bagnoli quarter (Naples town) in order to clarify the nature of the deep volcanic units underlying the caldera (De Natale et al., 2007). Seismic image and rock properties of the Phlegrean Fields caldera have been recently discussed through joint analysis and tomographic images based on the Serapis experiment dataset, carried out in the Gulf of Pozzuoli (Dello Iacono et al., 2009). The results regard the identification and characterization of the volcaniclastic layer filling the shallowest part of the Phlegrean caldera. The tomographic analyses have revealed a correlation among P-velocity anomaly at 0.5-0.75 km in depth, that tends to split into two parallel arcs and the position of volcanic dykes, buried volcanic structures and offshore fumaroles detected in the Gulf of Pozzuoli (De Bonatatibus et al., 1970; Pescatore et al, 1984; Milia 1998; 2010; Milia and Torrente, 2003; Aiello et al., 2012a; 2012b). The occurrence of these geological structures has suggested a highly fractured area, through which the magma and gases rise towards the surface. The analysis of the vertical component CMP gathers located on the southern rim of the Gulf of Pozzuoli has revealed the occurrence of a strong amplitude reflection event at 0.6 - 0.7 sec (twt) and corresponds to an approximate reflector depth of 600-800 m. Concerning the origin of the strong velocity contrast generating the high amplitude reflection event at about 0.6-0.7 sec (twt), it is worth noting that the stratigraphic profiles of onshore drill sites in the Mofete area (Fig. 1), located on the northern border of the caldera, show the evidence of a thick trachitic and latitic lava layer at about 750 m under tuff and tuffites post-caldera (Dello Iacono et al., 2009). While the volcanic activity gradually became subaerial in the northern part of the caldera, in the southern sector (i.e. the present Gulf of Pozzuoli), the conditions of marine sedimentation persisted since the caldera collapse except for the Wurmian phase (18 ky B.P.), when the sea level reached - 120 m and all the area was emerged above the sea level (Pescatore et al., 1984). The thick and shallow volcaniclastic layer, filling the Gulf of Pozzuoli during the post-caldera phases of activity of the Phlegrean Fields, could therefore include incoherent pyroclastic rocks and chaotic tuffs, highly water saturated because of marine sedimentation. The stratigraphy and geology of volcanic areas is an intriguing research theme, particularly applied to the case history of the Gulf of Pozzuoli (Naples Bay), representing the submerged border of the Phlegrean caldera. The state-of-the-art methodological aspects for mapping volcanic areas, applied also to case histories of Naples Bay, have been recently delineated, highlighting recent studies on the stratigraphy, structure and evolution of active volcanic terranes (Groppelli and Goette, 2010). New stratigraphic and volcanological studies, mainly onshore, dealing with the definition of volcanological units during the field survey and specific volcanological features, petrographic, geochemical and petrological studies and geophysical models have been recently presented (Lucchi et al., 2010); Tibaldi, 2010; Bonomo and Ricci, 2010; Palladino et al., 2010; Milia, 2010; Perrotta et al., 2010; De Vita et al., 2010). These studies allowed us to delineate the problems related to stratigraphy and volcanology of active volcanic districts of southern Italy, referring in particular to the Naples Bay. Apart the new stratigraphic setting of the offshore units, another aim of this paper is to produce a qualitative correlation of the seismo-stratigraphic data with marine magnetics already recorded both in the Gulf of Pozzuoli (Galdi et al., 1988) and in the Phlegrean offshore (Secomandi et al., 2003; Aiello et al., 2004) better constraining the volcanic nature of some seismic units. The integrated interpretation of Sparker profiles and magnetic anomaly maps will contribute to a better understanding of volcanic structures in the Gulf of Pozzuoli. Moreover, a correlation with the terrestrial geology of the Phlegrean Fields has been attempted in order to highlight tectonic and magmatic implications in the geological evolution of the Phlegrean Fields volcanic complex, intensively studied through field geology (Morhange et al., 2005; Bellucci et al., 2006; De Natale et al., 2007; Bodnar et al., 2007). 2. GEOLOGICAL SETTING The Gulf of Pozzuoli, offshore the Phlegrean Fields volcanic complex (Naples Bay, southern Tyrrhenian sea) is an inlet with limited dimensions, bounded seawards by several submerged volcanic banks (Pentapalummo Bank, Nisida Bank, Miseno Bank; Aiello et al., 2005). A morphological sketch map is shown in Fig. 2, representing several offshore morphological units (Aiello et al., 2012a). These units include the inner continental shelf, the central basin, the submerged volcanic banks and the outer continental shelf (Fig. 2). The inner shelf is located in the northern sector and grades into a central basin, located at 100 m of water depth through a -50 m deep shelf break and a steep slope. Proceeding seawards, the Pozzuoli central basin is limited by a belt of submarine volcanic highs and then grades into the outer shelf, located at water depths of - 140/-160 meters. The Phlegrean Fields are a volcanic district surrounding the western part of the Gulf of Naples, where volcanism has been active since at least 50 ky B.P. They correspond to a resurgent caldera with a diameter of 12 km (Phlegrean caldera; Rosi and Sbrana, 1987), resulting from the volcano-tectonic collapse induced from the eruption of the pyroclastic flow deposits of the Campanian Ignimbrite (35 ky B.P.). Coastal sediments ranging in age from 10 to 5.3 ky B.P. crop out 50 m above the sea level in the marine terrace of La Starza (Gulf of Pozzuoli), indicating a volcano-tectonic uplift of the caldera center (Dvorak and Mastrolorenzo, 1991; Morhange et al., 2005). The Quaternary volcanic area of the Phlegrean Fields is located in a central position within the graben of the Campania Plain (D'Argenio et al., 1973; Bigi et al., 1992). The pre-calderic volcanic activity developed in correspondence with small and scattered volcanic centers, erupting trachytic pyroclastics and lavas. The corresponding outcrop located at the Monte di Procida coastal cliff exhibits a thick subaerial pyroclastic sequence with several interbedded paleosols. It includes four main pumice fall beds, a welded pyroclastic flow deposit and dark lapilli and ashes erupted by the Fiumicello volcanic center (Procida island). The post-calderic volcanic activity developed during four main phases, individuated through radiometric age determinations and palaeogeographic evolution, in a time interval spanning from 35 ka to historical times, as established by deep wells located in the Mofete and San Vito geothermal areas (Rosi and Sbrana, 1987). 3. SEISMO-STRATIGRAPHIC AND MARINE MAGNETIC RESULTS The seismic profile L68_07 running from the western continental shelf of Pozzuoli Gulf and Nisida island has been interpreted to show the main stratigraphic and structural features of the Pozzuoli Gulf (Fig. 3). A sketch stratigraphic table, representing the key to the geological section reported in Fig. 3, describes the main characteristics and the possible chronostratigraphic attribution of the seismic units based on their stratigraphic relationships (Aiello et al., 2012a; 2012b). Large compressional features have been individuated on the seismic section, i.e. the Punta Pennata anticline, the central syncline of Pozzuoli Gulf and the Nisida anticline (Fig. 3). The structural lineaments involved in deformation of the volcaniclastic unit V3 (Fig. 3) have been produced by compressional events genetically related to the tectonic and magmatic events involving the Phlegrean Fields during the Late Quaternary. The Pozzuoli marine and volcanic sequences have been deformed by kilometer-scale folding during a main compressional event, probably due to tectonic inversions of the basin, already documented on the Tyrrhenian margin (Sartori et al., 2004; Jolivet et al., 2006; Gaullier et al., 2010). Based on seismo-stratigraphic evidence the uplift of the marine terrace of "La Starza", on which the town of Pozzuoli is located and the formation of an erosional platform on the inner Pozzuoli continental shelf are linked to an anticlinal crest. On the other side, the present-day basin depocenter is located on a syncline (Fig. 3). These folds formed during the deposition of the seismic unit G3 (Fig. 3), as evidenced by the wedging geometries of the seismic unit and the overall thinning towards the hinge of the anticline. Several magnetic studies have been carried out in the Neapolitan volcanic district (Nunziata and Rapolla, 1987; Secomandi et al., 2003; Paoletti et al, 2005). In particular, Paoletti et al. (2005) have presented a new detailed magnetic map of the whole Neapolitan active volcanic district, obtained by merging recently acquired airborne, land and marine magnetic measurements. The analysis of this magnetic dataset has enabled the characterization of the main buried volcanic structures, providing a better understanding of the connection between tectonism and volcanism in the study area. In the Gulf of Pozzuoli four magnetic sections have been constructed, NE-SW and NW-SE trending respectively (Galdi et al., 1988; Aiello et al., 2012a). The first one runs from Punta Pennata (Gulf of Pozzuoli) to the town of Pozzuoli (Via Napoli). The total magnetic intensity shows a trending with a magnetic minimum of - 80 nT in the central basin of the gulf (water depth of - 90 m) and a magnetic maximum of 70 nT near the Pozzuoli shoreline. The second one, translated of 2.4 km towards the southwest, shows a strong increase of magnetic gradient, due to the occurrence of the industrial system of Bagnoli. It has provoked the release in the environment mainly of metals derived by the burning of fossil oil coals and by remnants of industrial production. The third section, running from the Gulf of Pozzuoli to Punta dell'Epitaffio, shows a magnetic maximum at Bagnoli and a minimum near Nisida. The fourth one, running from Nisida to the historical centre of Pozzuoli (Rione Terra), shows a minimum at Nisida and a maximum at Rione Terra. In conclusion, the Phlegrean Fields are a volcanic area featuring a shallow Moho, a high thermal gradient, bradyseismic movements and shallow seismicity. The offshore portion of the Phlegrean Fields (continental shelf of the Pozzuoli Bay) has been investigated through high resolution seismic reflection profiles and volcanic and marine units are herein documented. An up-to-date geologic and stratigraphic setting of the seismic units is here furnished and discussed. Marine magnetic in the study area are interpreted. Some implications of the interpreted data on the tectonics and magmatism of the Phlegrean Fields volcanic complex are discussed. Regional geological concepts on the Phlegrean Fields in the framework of the Campania continental margin are recalled to support interpretations of the volcanic and tectonic context. 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An organic organization and implementation of the available geothermal data in the southern Italian Regions (Campania, Calabria, Puglia and Sicily) useful to improve the exploratlon and exploitation of geothermal reservoirs, is the alm of the CNR project "Evaluation of Geothermal Potential in Convergence Regions" (VIGOR), financed by the Inter-Regional Operational Programme "Renewable Energy and Energy Conservation" POI 2007-2013. In the Mondragone area hydrothermal evidences has been known since roman time, and this area has been chosen to further improve geothermal knowledge through new geophysical and geologicaI exploration survey. From the geological point of view, the area is defined by an horst structure (Mt. Massico) elongate in NE-SW direction, characterized by a succession of Triassic-Cretaceous dolomitic Iimestone and Miocene terrigenous sediments. The Quaternary deposits are widespread in the adjacent plans, where the continental and marine sediments, interbedded with Roccamonfina and Campi Flegrei pyroclastic deposits, filling the Garigliano, to NW, and Volturno, to SE, graben, separated by the Mt Massico horst throught a NE-SW striking normal faults (Bergomi et al., 1969). Field and seismic data indicate the study area is interested by deep normaI NE-SW and N-S striking faults, although ESE-WNW to E-W strike-slip left-Iateral faults are also present (Billi et al., 1997; Bruno et al., 2000). Probably these structural pattern plays an important role for the Mt. Massico groundwater circolation, partially confining such structure from the less permeable deposits of plains, and allowing the groundwater to f10w primarily to the aquifer of the Garigliano plain (Allocca et al., 2005). At the southeastern edge of the massif four sulfur hot springs with temperatures between 22°C and 50°C emerge. In particular two hot springs, ("La Calda" and "Della Salute", up to 50°C and 29°C respectively) are located at the foothill of the Miocene terrigenous succession of Mt. Pizzuto, closely to the coast (Bergomi et al., 1969, Corniello, 1988). While the other two ("S. Giuseppe" and "Mt. Petrino solforosa" up to 22°C and 28°C respectively) are located at the foothill of the Mt. Petrino carbonatic structure (Trumpy & Manzella, 2009). According to some authors, the hot springs are fed by groundwater carbonate aquifer, where the water is heated and enriched of endogenous gas (CO2 H2S), rising along the extensive and deep tectonic discontinuity present, further testified by the morphological evidenced (sinkholes) found all along the southeastern edge of the Mt Massico (Del Prete et al., 2004). Moreover the different temperatures and degrees of mineralization of the four springs are interpreted as closely Iinked to the rising speed and water-rock contact time (Corniello, 1988; Allocca et al., 2005). A delimited area of 20 km2 south-east of Mt. Massico has been chosen to be studied by means of geological and geophysical surveys and deep drilling to provide analytical information useful to develop an hydrogeological 3D model that will allows the application of technologies for direct explotation of heat from geothermal source.