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Marine geological maps of the Campania region have been constructed both to a 1:25.000 and to a 1:10.000 scale in the frame of the research projects financed by the Italian National Geological Survey, focusing, in particular, on the Gulf of Naples (Southern Tyrrhenian Sea), a complex volcanic area where volcanic and sedimentary processes strongly interacted during the Late Quaternary and on the Cilento Promontory offshore. In this paper, the examples of the geological sheets n. 464 “Isola di Ischia” and n. 502 “Agropoli” have been studied. The integration of the geological maps with the seismo-stratigraphic setting of the study areas has also been performed based on the realization of interpreted seismic profiles, providing interesting data on the geological setting of the subsurface. The coastal geological sedimentation in the Ischia and Agropoli offshore has been studied in detail. The mapped geological units are represented by: i) the rocky units of the acoustic basement (volcanic and/or sedimentary); ii) the deposits of the littoral environment, including the deposits of submerged beach and the deposits of toe of coastal cliff; iii) the deposits of the inner shelf environment, including the inner shelf deposits and the bioclastic deposits; iv) the deposits of the outer shelf environment, including the clastic deposits and the bioclastic deposits; v) the lowstand system tract; vi) the Pleistocene relict marine units; vii) different volcanic units in Pleistocene age. The seismo-stratigraphic data, coupled with the sedimentological and environmental data provided by the geological maps, provided us with new insights on the geologic evolution of this area during the Late Quaternary.

The correlation between onshore and offshore of the volcanic features in a complex volcanic field area is a difficult task, however, it is a fundamental step in order to better understand the geological evolution of such a complex area and for an assessment of geologic hazards. Ischia is a well exposed and densely populated volcanic field located in the Campania volcanic province of Italy. In order to improve our understanding of the recent volcanic history of Ischia Island, high-resolution seismic reflection profiles were used to identify volcanic and sedimentary features in the northern offshore. The volcano stratigraphy interpretation permitted us to recognize seismic units with a reflection-free/chaotic facies. These latter units have been associated with volcanic deposits and correlated to the main volcanic units outcropping on the northern coast of Ischia Island. They are limited in extent and interlayered with eight seismic units with continuous reflectors corresponding to clastic sedimentary units that were deposited during inter-eruptive phases. The main result of this work is the documentation of volcanic activity during the Holocene in the area offshore between Castello d'Ischia, Ischia Porto (mainly effusive products) and Punta della Scrofa (mainly shallow lava domes and dykes). The key volcanic units were mapped and 3D geological models were reconstructed. The reconstruction of the stratigraphic framework offshore a volcanic coast provides a pathway to the investigation of the stratigraphic relationships between inter-eruptive sedimentary deposits and volcanic units, and permits the assessment of a wide and continuous chronostratigraphic framework in a complex area. Furthermore, the onshore-offshore correlation of the main Holocene volcanic units allows us to better estimate their areal distribution, a critical factor in the hazard evaluation of a coastal volcanic area. The application of seismic volcano stratigraphy illustrates the remarkable possibilities that the study of submarine volcanic fields offers.

The depositional environments offshore of the Cilento Promontory have been reconstructed based on the geological studies performed in the frame of the marine geological mapping of the geological sheet n. 502 “Agropoli”. The littoral environment (toe-of-coastal cliff deposits and submerged beach deposits), the inner continental shelf environment (inner shelf deposits and bioclastic deposits), the outer continental shelf environment (outer shelf deposits and bioclastic deposits), the lowstand system tract and the Pleistocene relict marine units have been singled out. The littoral, inner shelf and outer shelf environments have been interpreted as the highstand system tract of the Late Quaternary depositional sequence. This sequence overlies the Cenozoic substratum (ssi unit), composed of Cenozoic siliciclastic rocks, genetically related with the Cilento Flysch. On the inner shelf four main seismo-stratigraphic units, overlying the undifferentiated acoustic basement have been recognized based on the geological interpretation of seismic profiles. On the outer shelf, palimpsest deposits of emerged to submerged beach and forming elongated dunes have been recognized on sub-bottom profiles and calibrated with gravity core data collected in previous papers. The sedimentological analysis of sea bottom samples has shown the occurrence of several grain sizes occurring in this portion of the Cilento offshore.

Submarine canyons are geomorphologic lineaments engraving the slope/outer shelf of continental margins. These features are often associated with significant geologic hazard when they develop close to densely populated coastal zones. The seafloor of Naples Bay is deeply cut by two incisions characterized by a dense network of gullies, namely the Dohrn and Magnaghi canyons, which develop from the shelf break of the Campania margin, down to the peripheral rise of the Eastern Tyrrhenian bathyal plain. Seismic-stratigraphic interpretation of multichannel seismic reflection profiles has shown that quaternary tectonics and recent to active volcanism have exerted a significant control on the morphological evolution and source-to sink depositional processes of the Dohrn and Magnaghi submarine canyons. The Dohrn canyon is characterized by relatively steep walls hundreds of meters high, which incise a Middle-Late Pleistocene prograding wedge, formed by clastic and volcaniclastic deposits associated with the paleo-Sarno river system during the Mid-Late Pleistocene. The formation of the Dohrn canyon predates the onset of the volcanic eruption of the Neapolitan Yellow Tuff (NYT), an ignimbrite deposit of ca. 15 ka that represents the bedrock on which the town of Napoli is built. Integrated stratigraphic analysis of high-resolution seismic profiles and marine gravity core data (C74_12) collected along the flanks of the eastern bifurcation of the head of Dohrn Canyon suggests that depositional processes along the canyon flanks are dominated by gravity flows (e.g., fine-grained turbidites, debris flows) and sediment mass transport associated with slope instability and failure.

Quaternary marine deposits of the Ischia island have been analyzed based on marine geological survey and sedimentological data. The Ischia island represents the emerged part of a large volcanic field, extending from the Procida island to the submerged volcanoes of the western Ischia offshore. The volcanic field develops over an area of about 42 km2, E-W trending, composed of calderas, such as the Ischia caldera, linked to the great explosive eruptions, plinian and ignimbritic ("Sintema del Rifugio di S. Nicola"). The grain-size analyses of sea bottom samples have evidenced the occurrence of gravelly sands, sands, silty sands, muddy sands, sandy silts and silts. The comparison of the obtained results with previous sedimentological data collected in the Ischia offshore, coupled with the construction of marine geological maps at the 1:10.000 scale has shown that the sands seem to prevail in the eastern Ischia offshore, while the gravelly sands, mainly bioclastic are located at the top of relict volcanic edifices, such as the Forio Bank (western Ischia offshore) and the Ischia Bank (south-eastern Ischia offshore). Moreover, the obtained data have evidenced the occurrence of rhodolith beds on the relict volcanic edifice of the Ischia Bank and the on the related parasitic vent and in the Ischia Channel, a morphological saddle located between the Ischia and Procida islands.

A main volcanic marker has been identified for the first time on the continental shelf of the northern Phlegraean Fields in the Gaeta Gulf (Campania region, eastern Tyrrhenian margin, Italy) by means of Subbottom Chirp profile grid and stratigraphic analysis of a core collected on the slope. In the seismic sections, the core bottom corresponds to the top of a continuous and parallel reflector (V) interbedded within the transgressive deposits of the Late Quaternary-Holocene depositional sequence. The Transgressive System Tract deposits are particularly thick compared to the majority of the transgressive deposits of other shelf settings. This might be due to the input of pyroclastic and volcanoclastic deposits related to the intense eruptive activity of the Campania Plain during the Late Pleistocene-Holocene time span. Undulations and pockmarks are the main morphological features of the sea floor and they might be linked to gas uprising, widely detected in the study area. The V reflector is located on the shelf from northeast to southwest at different depths, ranging from 10 ms (about 8 m) to 30 ms (about 25 m) below sea floor and it can be mapped down to the continental slope. The geological calibration of this continuous reflector coupled with tephrostratigraphic analysis, allowed to correlate it with the Neapolitan Yellow Tuff deposits emplaced at Phlegraean Fields at ca. 15 ka.

Magnetic theory and application to a complex volcanic area located in Southern Italy are here discussed showing the example of the Gulf of Naples, located at Southern Italy Tyrrhenian margin. A magnetic anomaly map of the Gulf of Naples has been constructed aimed at highlighting new knowledge on geophysics and volcanology of this area of the Eastern Tyrrhenian margin, characterized by a complex geophysical setting, strongly depending on sea bottom topography. The theoretical aspects of marine magnetometry and multibeam bathymetry have been discussed. Magnetic data processing included the correction of the data for the diurnal variation, the correction of the data for the offset and the leveling of the data as a function of the correction at the cross-points of the navigation lines. Multibeam and single-beam bathymetric data processing has been considered. Magnetic anomaly fields in the Naples Bay have been discussed through a detailed geological interpretation and correlated with main morpho-structural features recognized through morpho- bathymetric interpretation. Details of magnetic anomalies have been selected, represented and correlated with significant seismic profiles, recorded on the same navigation lines of magnetometry. They include the continental shelf offshore the Somma-Vesuvius volcanic complex, the outer shelf of the Gulf of Pozzuoli offshore the Phlegrean Fields volcanic complex, the relict volcanic banks of Pentapalummo, Nisida and Miseno, the Gaia volcanic bank on the Naples slope, the western slope of the Dohrn canyon, the Magnaghi canyon’s head and the magnetic anomalies among the Ischia and Procida islands.

A geologic and geomorphologic study aimed at solving some geological and geotechnical problems, regarding the massive seepage of meteoric waters in the coastal cliffs of the Island of Procida (Naples Bay, southern Italy), composed of both tuffs and loose pyroclastic deposits, has been carried out in the geosites of Terra Murata (Middle Ages village and coastal cliff towards the Corricella Bay) and Centane-Panoramica (coastal cliff facing on the Tyrrhenian sea). A detailed geologic and geomorphologic survey has allowed to suggest solutions to the applied geological and geotechnical problems related to the occurrence of massive seepages of waters at the physical interface between pyroclastic rocks and loose pyroclastic deposits, characterized by different density, permeability and porosity and also controlled by a dense network of fractures, involving the pyroclastic deposits cropping out in the selected areas. Field sampling and geotechnical laboratory analyses have been carried out to calculate the values of main geotechnical parameters of the yellow tuffs cropping out at the Terra Murata promontory. At the same time, a detailed monitoring of the seepages of waters has been carried out through a detailed geological survey of the tuff outcrops of the promontory. The obtained results have suggested a strong control from both the geomorphologic instability of the coastal cliff and tectonic setting. At the Centane-Panoramica geosite the geological survey, coupled with geotechnical analyses and standard penetrometric tests, has accordingly evidenced that the geomorphologic instability was mainly concentrated in the sectors of the tuff coastal cliffs facing seawards towards the Tyrrhenian sea.

This book contains twelve chapters dealing with the studies on volcanoes, their geological and geophysical setting, the theoretical aspects and the numerical modeling on volcanoes, the applications of volcanoes to industry and the impact of volcanoes on the human health, in different geological settings and using several techniques and methods, including the volcanology, the seismology, the statistical methods to assess the correlation between seismic and volcanic activity (modified Ripley's K-function to regional seismicity), the field geological survey of volcanic successions, the analytical methods for petrologic analysis, the petrography of the volcanic rocks with the individuation of the modal compositions of volcanic rocks and their comparison with major elements and trace elements in variation diagrams and the argon isotopic measurements performed through the peak height comparison (unspiked) method. The oceanographic methods have also been applied to case studies of submarine volcanic edifices located in the Canary Islands (Atlantic Ocean), including the sampling of the water column with a conductivity-temperature-depth sensor (CTD) rosette with 24 Niskin bottles, in order to determinate key physical and chemical parameters, such as the total-scale pH, the total dissolved inorganic carbon (C), the total alkalinity (A), the total dissolved inorganic carbon (C), the total alkalinity (A), the temperature, the salinity and the dissolved oxygen. Problems of volcanic risk mitigation have also been treated, regarding the eruption disasters in Indonesia, a country where a high number of people lives next to the volcanoes and characterized by the lacking of a public awareness of the eruption disasters. Petrographic methods have been successfully applied to the study of the Cretaceous magmatism of the layered gabbroids of the Chukotka region (Pekulney Ridge, Russia) and geodynamic implications have been successfully established through geological and petrographic studies. The relationships between the mantle wedge, the convective heat and mass transfer, the infiltration metasomatism, the zoning and the mathematical models have been applied to the comprehension of complex volcanic areas through the theoretical aspects of volcanic studies on magmatic chambers coupled with numerical modeling, including FEMs (Finite Element Models) in the individuation of volcanic deformations. Book chapters are separated into five main sections: (i) introduction, (ii) geological and geophysical setting of volcanoes, (iii) theoretical aspects and numerical modeling of volcanoes, (iv) applications of volcanoes to industry and (v) impact of volcanoes on the human health. There is one chapter in the first section on the Introduction, the Introductory Chapter. In the second section there are five chapters, dealing with the correlation between seismic and volcanic activity at the Vesuvius volcano, with the exploration of the base of the Zao stratovolcano in the north-eastern Japan, with the volcanic emissions of the Tagoro submarine volcano in the Canary Islands and their impact on the physical and chemical properties of the oceanic waters, with the characteristics of the volcanic eruptions in Indonesia and the problems of risk mitigation of volcanic disasters, and finally, with the geologic and petrographic study of Cretaceous volcanites of the Pekulney Ridge (Russia) and corresponding geodynamic implications. In the third section there are three chapters, the first one dealing with the dynamics of convective heating of the mantle and crustal rocks in the seismic focal zone of the Kamchatka region and the genetically-related volcanic arcs, characterized by the occurrence of compressive stresses and by the compaction of the heterophase medium, the second one regarding the numerical methods of volcanic deformation through InSAR methods, showing a systematic approach to the quantitative simulation of geodetic data with finite element models (FEMs) in the general framework of a protocol for the modeling of deformations in volcanic areas and the third one showing the mechanics of the magmatic chambers under the volcanoes, referring to the Yellowstone caldera, which, due to its large volume, owes the critical overpressure necessary to start the volcanic eruption, requiring large volumes of magmas and fluids. In the fourth section there are two chapters, the first one dealing with the use of volcanic scoriae in the cement replacement, a common practice in the construction industry, as concrete mixes, showing the chemical and mineralogical composition of the scoria samples coming from 36 different countries and calculating some equations of estimated depending on the analyzed data and the second one regarding the use of volcanic glasses or obsidians as absorbents, highlighting that the volcanic glasses represent amorphous phyllosilicates formed through a rapid magmatic cooling and that the macroporosit. y of the volcanic glasses allows to host biomolecules, tensioactives and dyes.

This is the introductory chapter of the book "Volcanoes: geological and geophysical setting, theoretical aspects and numerical modelling, applications to industry and their impact on the human health". In this chapter, the research themes studied in this book have been introduced referring to the geological and geophysical setting of volcanoes, pertaining, in particular, the correlation between seismic and volcanic activity in volcanic edifices of Southern Italy (Somma-Vesuvius) carried out to a regional scale, the volcanic emissions of the submarine edifice of the Tagoro volcano (Canary Islands, Atlantic Ocean) and the corresponding implications on the chemical and physical properties of the oceanic water, the volcanological studies on the base of the volcanoes and the discovery of a new volcanic edifice, namely the Hiyamizuyama volcano, allowing to evaluate the long-term variations of volcanic and magmatic processes in the north-eastern Japan, the volcanic eruptions in Indonesia, a land hosting 147 volcanoes (76 active volcanoes) spreading along the islands of Java, Lesser Sunda, Sumatra and Celebes and mostly characterized by stratovolcanoes and finally, the geologic, petrographic and geodynamic study of the layered gabbroids of the Pekulney Ridge, a complex volcanic structure located in the north-eastern Russia. Moreover, in this book, significant theoretical aspects and numerical modelling of volcanoes have been addressed, including, in particular, the volcanic dynamics of the convective heat and of the mass transfer in the seismo-focal areas of the Kamchatka Region, including the related volcanic arcs, the modelling of the elastic deformation of volcanoes through the development of computational tools for inverse analyses of geodetic data, which have evidenced the mechanical complexity of the volcanic systems and finally, the mechanical aspects of the magmatic chambers and their relationships with the fluxing of CO2, referring to the Yellowstone magmatic chamber, whose large volume has required additional large volumes of magmas and fluids in order to trigger the volcanic eruption. In this book, significant applications of volcanic studies to industry have also been presented, focusing, in particular, on the use of volcanic scorias and natural pozzolans as cement replacement in the construction industry based on the concrete mixes by analyzing their setting times, the compressive strength, the water permeability and the chloride penetrability and moreover, on the use of volcanic glasses as adsorbents for industrial aims and scopes, being materials displaying a low thermal conductivity, a low density and a high resistance to the fire and perlite aggregate plasters. The volcanic glasses have also been often used as starting materials in the synthesis of clay minerals, as the smectites and the zeolites. The impact of volcanoes on the human health is significant, referring to both the volcanic deposits and to the volcanic emissions. In this book, the impact of the volcanic emissions on the human health has been mainly examined, highlighting that the exposure to volcanic emissions can influence the health of people living in the surroundings of the volcano in many ways (dermal and ocular irritation, cardiologic and pulmonary exacerbations and cancer). Moreover, the volcanic ashes which have been deposited in a subaqueous environment may produce significant variations in the chemistry of the surface waters and may increase the risk of exposure to metals by drinking the water.

The study of the seismo-stratigraphic architecture of Late Quaternary-Holocene volcanic and sedimentary units in the Ischia Island offshore and their correlation with the coastal units of the adjacent onshore sectors allowed for a detailed reconstruction of the seismic stratigraphy of the northern, southern and western sectors of the island. Five (southern Ischia) to nine (western Ischia) seismic units and related seismic facies were identified. The volcanic areas and their detailed seismo-stratigraphic setting fit well in the geological context of a passive margin and confirm that the stratal architecture in the Ischia Island Quaternary marine deposits is controlled by the interaction between glacio-eustatic fluctuations, volcanism, tectonics and sedimentary supply.

This is the introductory chapter of the book “Seismic and sequence stratigraphy and integrated stratigraphy - new insights and contributions.” In this chapter, the research themes studied in this book have been introduced referring to the seismo-stratigraphic and sequence stratigraphic techniques and methodologies, pertaining, in particular,the fine-grained shales and the alluvial systems, the seismo-stratigraphic features of Late Miocene deposits offshore the northern Taiwan and to the integrated stratigraphic studies, including the stratigraphy of the Jurassic deposits in the Irkutsk sedimentary basin studied through lithologic and paleobotanical data, the disconformities in stratigraphy, reviewing their theoretical concepts and studying selected examples from Paleozoic successions and the integrated stratigraphy of the foreland basin of the Andean fold and thrust belt. The topics and the research themes developed in this book are of the great actuality and should have a good impact on the scientific research community. In fact, the sequence stratigraphic studies and the seismo-stratigraphic concepts have been typically developed on the deposits pertaining to the marine environment in a geodynamic context of a passive,Atlantic-type continental margin [1–13]. In this book, instead, emphasis is given to the sequence stratigraphic studies performed on the alluvial systems and on the fine-grained shales.

New morpho-bathymetric and tectono-stratigraphic data on Naples and Salerno Gulfs, derived from bathymetric and seismic data analysis and integrated geologic interpretation are here presented. The CUBE(Combined Uncertainty Bathymetric Estimator) method has been applied to complex morphologies, such as the Capri continental slope and the related geological structures occurring in the Salerno Gulf.The bathymetric data analysis has been carried out for marine geological maps of the whole Campania continental margin at scales ranging from 1:25.000 to 1:10.000, including focused examples in Naples and Salerno Gulfs, Naples harbour, Capri and Ischia Islands and Salerno Valley. Seismic data analysis has allowed for the correlation of main morpho-structural lineaments recognized at a regional scale through multichannel profiles with morphological features cropping out at the sea bottom, evident from bathymetry.Main fault systems in the area have been represented on a tectonic sketch map, including the master fault located northwards to the Salerno Valley half graben. Some normal faults parallel to the master fault have been interpreted from the slope map derived from bathymetric data. A complex system of antithetic faults bound two morpho-structural highs located 20km to the south of the Capri Island. Some hints of compressional reactivation of normal faults in an extensional setting involving the whole Campania continental margin have been shown from seismic interpretation.

The interactions between Late Quaternary volcanic and sedimentary processes in the Naples Bay, Southern Tyrrhenian sea are here discussed through the results of the marine geological survey at the 1:10.000 scale. The example of the geological map n. 465 "Isola di Procida", herein presented, has put in evidence the stratigraphy of marine Quaternary deposits and related volcanic seismic units. The volcanic deposits cropping out in the Procida island have been explained as the result of eruptions coming from local eruptive centres. The geological survey carried out onshore indicate the occurrence of several pyroclastic units linked to the eruptive activity of the Ischian and Phlegrean volcanic complexes, interstratified with the products erupted by local centres. The occurrence in the pyroclastic sequences of Ischia and Procida islands of several marker horizons and their stratigraphic correlations have allowed to reconstruct the volcanological evolution of the two islands and the interactions with sedimentary processes at the scale of the whole Tyrrhenian margin. Fifteen geological maps at the scale 1:10.000 covering the whole Naples Bay have been constructed based on the interpretation of marine geological and geophysical data. The stratigraphic relationships between the lithostratigraphic units and the eruptive deposits have testified the activity of several volcanic monogenic centers, whose products are interstratified with marine and continental deposits of the Late Quaternary depositional sequence.

A multi-proxy analysis of Volturno River prodelta deposits in the outer shelf of Northern Phlegraean margin (Eastern Tyrrhenian Sea) has been carried out to reconstruct the sedimentary processes acting during recent times. The late Holocene sediments were characterized through Subbottom Chirp profiles coupled with sedimentological and petrophysical data. The chronostratigraphic framework was achieved by means of colorimetric parameter a* correlations with nearby dated marine sediment. A time interpretation of about 2,300 years BP is estimated for the sedimentary record collected in the cores. Seismic stratigraphic analysis shows late Holocene outer shelf deposits, characterized by fluid escape features and small-offset faults. However, the undisturbed sedimentation and the preservation of an internal geometry at decimetre scale, as detected by the sedimentological and petrophysical analysis, indicates a slow sliding without sediment reworking for this sedimentological body. So far a possible recent (

The marine geological map n. 502 “Agropoli”, located offshore the Cilento Promontory, southern Italy, is here described and the regional geology interpreted, particularly referring to water depths between the 30 and 200 m isobaths. The geologic map has been constructed in the frame of a research program financed by the National Geological Survey of Italy (CARG Project), finalized to the construction of up-to-date cartography of the Campania region. Geological and geophysical data on the continental shelf and slope offshore of the Southern Campania region have been collected in the study area, bounded northwards by the Salerno Gulf and southwards by the Policastro Gulf. A high resolution multibeam bathymetry allowed for the construction of a marine digital elevation map; sidescan sonar profiles also have been collected and interpreted. The latter, merged to the bathymetry, have represented the base for the marine geologic cartography. The integrated geologic interpretation of seismic, bathymetric and sidescan sonar data has been calibrated by sea-bottom samples. The morpho-structures and the seismic sequences overlying the outcrops of acoustic basement reported in the cartographic representation have been studied in detail using single-channel seismics. The interpretation of seismic profiles has been a support for the reconstruction of the stratigraphic and structural setting of the Quaternary continental shelf successions and the outcrops of rocky acoustic basement in correspondence to the Licosa Cape morpho-structural high. These areas result from the seaward prolongation of the stratigraphic and structural units, widely cropping out in the surrounding emerged sector of the Cilento Promontory. The cartographic approach is based on the recognition of laterally coeval depositional systems, interpreted in the frame of the system tracts of the Late Quaternary depositional sequence. We present evidence of now subaqueous terraces inferred to be palaeoshorelines representing past sea-level positions and tentatively correlated these to oxygen isotopic stratigraphy.

High-resolution seismic stratigraphy of the Gulf of Pozzuoli has been studied to discuss volcanological implications on geological evolution of the Phlegrean Fields volcanic complex. A new seismo-stratigraphic framework of the Gulf of Pozzuoli is provided based on the geological interpretation of Sparker profiles, showing thirteen seismic units. The seismo-stratigraphic analysis has evidenced that the marine units prevail in the eastern Pozzuoli offshore (Baia town) while the volcanic units prevail in the western Pozzuoli offshore (Pozzuoli town). Two deep volcaniclastic units appear to be related to the northern margin of the Pentapalummo Bank, a relict volcanic edifice located in the outer Pozzuoli shelf. The Pozzuoli basin filling is made up of five seismic units, marine in origin, whose internal configuration is mostly characterized by parallel reflectors. The marine units are overlain by three volcanic units, whose origin is probably pyroclastic, both due to their seismic facies and to their deposition in palaeo-morphological depressions. A wedge-shaped seismic unit, acoustically transparent, has been interpreted in the Gulf of Pozzuoli as the Neapolitan Yellow Tuff deposits. Lowstand and highstand deposits, pertaining to the Late Quaternary depositional sequence are, respectively, characterized by progradational and parallel seismic reflectors, located in the Gulf of Pozzuoli. Different models on the geological structure of the Phlegrean caldera and its present-day unrest state have been taken into account to improve the discussion of the volcanological aspects related with the seismo-stratigraphic setting of the Gulf of Pozzuoli, representing the submerged border of the caldera itself. In the frame of research themes pertaining to the volcanic geology of the Campania continental margin, a stratigraphic correlation between the Gulf of Pozzuoli and Ischia island volcanic areas, whose geological data have been previously collected, has been performed and is herein presented, highlighting new interesting implications and results on the geology of the Naples Gulf.

The geological evolution of coastal and marine environments offshore the Cilento Promontory through marine geological mapping is discussed here. The marine geological map n. 502 “Agropoli,” located offshore the Cilento Promontory (southern Italy), is described and put in regional geologic setting. The study area covers water depths ranging between 30 and 200 m isobaths. The geologic map has been constructed in the frame of a research program financed by the National Geological Survey of Italy (CARG Project), finalized to the construction of an up-to-date cartography of the Campania region. Geological and geophysical data on the continental shelf and slope offshore the southern Campania region have been acquired in an area bounded northward by the Gulf of Salerno and southward by the Gulf of Policastro. A high-resolution multibeam bathymetry has permitted the construction of a digital elevation model (DEM). Sidescan sonar profiles have also been collected and interpreted, and their merging with bathymetric data has allowed for the realization of the base for the marine geologic cartography. The calibration of geophysical data has been attempted through sea-bottom samples. The morpho-structures and the seismic sequences overlying the outcrops of acoustic basement reported in the cartographic representation have been studied in detail using single-channel seismics. The interpretation of seismic profiles has been a support for the reconstruction of the stratigraphic and structural setting of the Quaternary continental shelf successions and the outcrops of rocky acoustic basement in correspondence to the Licosa Cape morphostructural high. These areas result from the seaward prolongation of the stratigraphic and structural units, widely cropping out in the surrounding emerged sector of the Cilento Promontory. The cartographic approach is based on the recognition of laterally coeval depositional systems, interpreted in the frame of system tracts of the Late Quaternary depositional sequence.

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.

New insights on the deep regional geological structure of the Naples Bay are herein proposed through the constraints of seismic interpretation. Regional geoseismic sections along the Ischia-Capri-Volturno alignment of the Campania continental margin have been constructed. Main regional morpho-structures are: the Banco di Fuori, a morpho-structure high of Meso-Cenozoic carbonates, bounding southwarrds the Naples Bay; the Dohrn canyon, separating the eastern side of the Bay, where sedimentary seismic sequences crop out, from the western one, where volcanic seismic units prevail; the Capri structural high, a sedimentary high related to regional uplift of Meso-Cenozoic carbonates along the Capri-Sorrento alignment; the Magnaghi canyon, eroding the Mg volcanic seismic unit southwards of the Procida islands; the Capri basin, a deep basin located south of the Naples Bay, filled by Pleistocene-Holocene sediments overlying Meso-Cenozoic carbonatic unit; the Salerno Valley, a half-graben filled by three seismic units corresponding to Quaternary marine deposits, overlying chaotic sequences related to the "Flysch del Cilento" Auct.; the Volturno basin, filled by four marine to deltaic seismic sequences, frequently alternating with volcanoclastic levels, overlying deep seismic units, correlated with Miocene flysch deposits (sands and shales) and Meso-Cenozoic carbonates. On the Naples slope between the Dohrn and Magnaghi canyons a large volcanic edifice, only magnetically known, deeply buried under Quaternary volcanites and genetically related to the Procida volcanic complex, has been modelled through seismic interpretation.

We discuss a mathematical model of wave and run-up generated ancient submarine landslides in the canyons of the Bay of Naples (Magnaghi-Dohrn canyon system). The morpho-bathymetry and submarine gravity instabilities of such incisions have been investigated through the interpretation of a high resolution DEM. THe canyons are located in a sector of the bay where there is a variable interaction of volcanic activity (Phlegrean Fields and Ischia and Procida islands) with sedimentary processes due to the Sarno-Sebeto rivers. At present the Naples canyon-system is inactive, as evidenced by the Holocene sedimentary drapes deposited during the present sea-level highstand, but gravity instabilities occurred in the recent past at the canyons'heads. In particular the Dohrn Canyon is characterized by a double regressive head, while the Magnaghi Canyon shows a trilobate head, formed by the junction of three main tributary channels and coincident with the retreat of the shelf break around the 140 m isobath. The results of a simulation of failures in the above source areas shows that the amplitude of wave run-up, expressed in terms of the sea floor depth percentage, may range up to 2.5% of the water depth at the sea bottom. The results of a simulation of failures at the above source areas show that the amplitude of wave run up, expressed in terms of the seafloor depth percentage, may range up to 2,5% of the water depth at the sea bottom.

A three-dimensional reconstruction of a large volcanic structure located offshore the town of Torre del Greco (Naples Bay, Southern Tyrrhenian Sea, Italy) and representing the seaward prolongation of the Vesuvius volcano has been carried out using integrated geological interpretation of existing densely-spaced high-resolution seismic and magnetic profiles. This reconstruction has provided new insights into the knowledge of marine geophysics and volcanology of Vesuvius, one of most studied volcanoes in the world. Seismic stratigraphy of the volcanic structures shows acoustically-transparent seismic facies and high contrasts of acoustic impedance with respect to the overlying sediments. The structures have mound-shaped external geometry and average dimensions measurable in terms of kilometres. The base of the Torre del Greco volcanic structure overlies the volcanic seismic unit correlated to the ‘Campanian Ignimbrite’ pyroclastic flow deposits. Consequently, no contrast of acoustic impedance between the two volcanic units is clearly evident on the seismic profiles. The top of the structure is irregular and eroded and shows several culminations. The three-dimensional reconstruction of the Torre del Greco structure has been carried out using seismic constraints and correlations of volcanic structure to bathymetry. The sea floor topography is compared to the top of the Torre del Greco volcanic structure represented by contour depth of corresponding seismic horizons. Proceeding from south-east to north-west there is a good correspondence between the sea floor topographic surface and the top of the volcanic structure, which does not crop out at the sea-bottom. The rising of the volcanic structure in proximity to the sea-bottom corresponds to the occurrence of topographic undulations of up to ten metres. This evidence is confirmed by the interpretation of seismic profiles, showing three main vertical culminations of the volcanic structure, where the overlying sediment drape is significantly reduced. These culminations are linked to magnetic anomaly extremes, having values ranging between 250–350 nT. A striking coincidence between the long-shaped topographic high on the sea floor (towards the east) and the high in the top of the volcanic structure underneath can be explained as a consequence of sea floor deformation due to the underlying volcanic culminations. Smaller volcanic mounds, buried and fossilized by marine sediments, are not related to any magnetic anomaly, probably due to their composition of volcanic tuffs.

New high resolution seismic data (Subbottom Chirp) coupled to high resolution Multibeam bathymetry collected in the frame of the Stromboli geophysical experiment aimed at recording active seismic data and tomography of the Stromboli Island are here presented. The Stromboli geophysical experiment has been already carried out based on onshore and offshore data acquisition in order to investigate the deep structure and the location of the magma chambers of the Stromboli volcano. A new detailed swath bathymetry of Stromboli Island is here shown and discussed to reconstruct an up-to-date morpho-bathymetry and marine geology of the area compared to the volcanologic setting of the Aeolian Arc volcanic complex. Due to its high resolution the new Digital Terrain Model of the Stromboli Island gives interesting information about the submerged structure of the volcano, particularly about the volcano-tectonic and gravitational processes involving the submarine flanks of the edifice. Several seismic units have been identified based on the geologic interpretation of Subbottom Chirp profiles recorded around the volcanic edifice and interpreted as volcanic acoustic basement pertaining to the volcano and overlying slide chaotic bodies emplaced during its complex volcano-tectonic evolution. They are related to the eruptive activity of Stromboli, mainly poliphasic and to regional geological processes involving the intriguing geology of the Aeolian Arc, a volcanic area still in activity and needing improved research interest.

High resolution seismic reflection profiles (Sparker Multitip) offshore southern Ischia island (Naples Bay) are here presented, together with a geological interpretation of their volcanic, structural and sedimentary features. In this frame, new seismo-stratigraphic evidences on buried volcanic structures and overlying Quaternary deposits of the south-eastern offshore of Ischia island are discussed to highlight their implications on the marine geophysics and volcanology. The Ischia Bank is a large and flat relic volcanic 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 centre of the pyroclastic fall cropping out onshore in the eastern sector of the island, ranging in age from 8 to 6 ky B.P.. 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 running in the south-eastern Ischia offshore, across buried volcanic structures, are finally presented and discussed.

A mathematical model for tsunami waves and run-up generating by submarine landslides in the canyons of the Bay of Naples (Magnaghi-Dohrn canyon system) is here discussed. The morpho-bathymetry and submarine gravity instability of the Naples canyons has been studied through the interpretation of a high resolution DEM. The Dohrn and Magnaghi canyons are controlled by the interaction between volcanic activity (Phlegrean Fields and Ischia and Procida volcanic complexes) and sedimentary processes related to Sarno-Sebeto rivers. The abrupt termination of the Ammontatura channel (prolonging of the Dohrn western branch on the Naples outer shelf) against the Nisida volcanic bank was older or contemporaneous with the eruption of the Neapolitain Yellow Tuff (NYT). This suggests that the Dohrn canyon system is older than the NYT, which forms the main basis of the Naples town. This implies that most part of the canyon system activity is older than 11-12 ky B.P., age of the NYT. Despite the canyon system is actually inactive, the main submarine instabilities have been identified and mapped around the Dohrn western branch, from the head to the middle of the branch, on the continental slope southwards of the Magnaghi canyon and on the north-western slope of the Banco di Fuori carbonatic high. The results of a simulation of failures in the above source areas show that the amplitude of wave run-up, expressed in terms of the sea fl oor depth percentage, may range up to 2.5 % of the water depth.

The structural and stratigraphic framework of Puglia offshore between the Gargano promontory and the town of Brindisi (southern Adriatic Sea) has been analysed based on 1700 km of multichannel seismic profiles and 10 exploratory wells. The area includes two different geodynamic settings: (1) part of the undeformed Apenninic foreland (“Apulian carbonate Platform”), consisting mainly of shallow water Mesozoic carbonates, and (2) part of the southern Adriatic Basin, which represents the foredeep of the Hellenic thrust system. A Mesozoic slope, buried by Tertiary clastics and corresponding to the edge of the Apulian carbonate platform, is observed on seismic data. The present physiography of the escarpment is the result of an erosional retreat mainly developed during the Tertiary and related to the subsidence of the South Adriatic Basin; at the same time carbonate facies belts, as evidenced by well data, seem to suggest that in some sectors of the margin the original Mesozoic physiography has been preserved and fossilized. Three seismostratigraphic units, separated by regional or local unconformities, have been distinguished in the Neogene clastic sequence of the South Adriatic Basin. Significant deformations in the sedimentary cover are represented by various antiforms. One of these antiforms, named the “Gondola” ridge, is an elongated, positive structure deforming the pre-Tertiary basement. The western sector of the Gondola ridge belongs to a major E-W strike-slip lineament extending on land in the Gargano promontory. In the eastern part of the area in question some tectonic features, resembling “pop up”-like and thrust antiforms, are arranged along an arcuate pattern named here “Grifone” trend. The Grifone trend structures indicate a post-Pliocene tectonism probably related to the late stages of the Dinaric-Hellenic orogenesis. The recent westward migration of the Hellenic fold and thrust belt can be demonstrated by the South Adriatic foredeep shift during the last 5–6 million years.

Stromboli island, located in the southern Tyrrhenian sea, is the emerged part (about 900 meters above sea level) of an approximately 3 kilometer-high stratovolcano. Its persistent Strombolian activity, documented for more than 2000 years, is sometimes interrupted by lava effusions or major explosions. Despite the number of recently published geophysical studies aimed at clarifying the volcano's eruption dynamics, the spatial extent and geometrical characteristics of its plumbing system remain poorly understood. In fact, knowledge of the inner structure and the zones of magma storage is limited to the upper few hundred meters of the volcanic edifice (Chouet et al., 2003; Mattia et al., 2004) and P and S wave velocity models are available only in restricted areas (Petrosino et al., 2002). Over the past few years, Stromboli has experienced an increase in its activity, which started with the eruptive crisis of December 2002 to July 2003. The observed variations in Stromboli's eruptive behavior and the occurrence in December 2002 of a tsunami and in April 2003 of a paroxysmal vulcanian-type event with strong explosions and lava flows (Bonaccorso et al., 2003), have focused attention on the need to determine more suitable internal structure and velocity models of the volcano. To meet this need, a seismic tomography experiment through active seismics using air gun sources was done. A preliminary two-dimensional (2-D) tomographic study is presented here.

In this paper we present a correlation between volcanic structures and magnetic anomalies in the Gulf of Naples (Southern Tyrrhenian Sea) based on high resolution magnetic profiling. A densely spaced grid of magnetic profiles coupled with multichannel seismics (seismic source Watergun 15 cubic inch) was recorded in the Gulf of Naples, representing an active volcanic area during the Late Quaternary (volcanic centers of Somma-Vesuvius, Phlegraean Fields and Ischia and Procida islands). The dataset was collected during the oceanographic cruise GMS00-05 which took place during October-November 2000 in the South Tyrrhenian Sea onboard of the R/V Urania (National Research Council, Italy). Shallow volcanic structures in the subsurface of the gulf were recognized by seismo-stratigraphic analysis of high resolution profiles; the volcanic nature of some of these structures was inferred identifying the magnetic anomalies on a high resolution magnetic anomaly map of the gulf. Even if qualitative, the correlations between seismic and magnetic profiles allow us to better assess the geological structure of the Gulf of Naples.

The Salento continental shelf of Apulia (southern Adriatic) shows a complex stratigraphic architecture of Pleistocene prograding wedges that records the effects of the interplay of sediment accumulation, glacio-eustatic sea level changes, and regional tectonics. The interpretation of high-resolution seismic reflection profiles reveals three ravinement surfaces, extending landwards from the shelf break and showing low gradients. They have been considered to be stratigraphic markers and tentatively correlated to the oxygen curves of the isotopic stratigraphy. Even if direct dating of seismic sequences and corresponding unconformities is lacking, this correlation is well supported by the lateral extent and continuity of the ravinement surfaces, recognized in the whole investigated area. Similar qualitative correlation of unconformities with the curves of oxygen-isotope stratigraphy has been already used by other authors in different case histories of continental shelves of both active and passive margins. Moreover, in the study area the regional geological framework suggests that during the Middle Pleistocene the rate of tectonic uplift interacted with the rate of glacio-eustatic fluctuations, producing the deposition of forced-regression systems tracts. The forced-regression prograding wedge that enlarged the shelf by about fifteen kilometers is here dated as Middle Pleistocene. Starting from the upper part of the Middle Pleistocene, the stratigraphic architecture of the prograding wedges was controlled mainly by glacio-eustatic sea-level changes forced by short-eccentricity cycles. This is suggested by the stratigraphic architecture of the last two prograding wedges, interpreted as incomplete fourth-order depositional sequences and consisting of forced regression,lowstand, and transgressive systems tracts. The eustatic signal as an expression of the Earth’s orbital cyclicity (short eccentricity)appears overwhelming with respect to the tectonic one, and its prominence suggests a decrease in the rate of uplift of the Apulian foreland during the last 250 ky.

We here present and discuss the results of the analysis and qualitative interpretation of two magnetic surveys performed in the Bay of Naples in 1998 and 2000. A map of the Bay of Naples based on the data acquired during these surveys has already been published by the Italian CNR-IAMC Research Institute. We re-processed the same data to produce maps of the pole reduced, analytic signal and horizontal derivative data and correlated them with the bathymetry and the gravimetric data of the area. The analysis shows strong anomalies in the NW and NE volcanic areas of the Bay of Naples, while the central area seems magnetically quiet. In the Phlegrean area the maps clearly show the southern rim of the Phlegrean caldera and demonstrate that while the Magnaghi Canyon is correlated to gravimetric highs and magnetic structures, and can therefore be interpreted as an active lineament, most of Dohrn Canyon is not characterized by volcanic activity and does not correlate to any gravimetric or magnetic structures. An important round-shaped magnetic anomaly is for the first time identified in the central slope of the gulf between the two canyons, probably correlated to a large buried volcanic edifice. In the Vesuvian area some intense circular anomalies, aligned in the NNW–SSE direction, are localized in the Torre del Greco and Torre Annunziata offshore, related to the submerged part of Vesuvius and possibly connected to buried vents.