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Widespread volcanism has been known in the Sicilian Channel for a long time, even if some submarine volcanoes have only recently been discovered. Most of this volcanism formed along the NNE-trending transfer zone known as the Capo Granitola–Sciacca Fault Zone, while others, such as the islands of Pantelleria and Linosa, are associated with the continental rift zone that has developed since the early Pliocene in the central part of the Sicilian Channel through the formation of three deep tectonic troughs (Pantelleria, Linosa and Malta). However, the origin of a group of five volcanoes (here called "Tetide volcanic cluster") that form a NW-SE alignment on the eastern edge of the Adventure Plateau is not yet known. In this work, we hypothesize that this volcanic alignment may represent the remnants of a failed rift attempt that was unable to generate another tectonic trough in the Sicilian Channel. Based on seismic sections and gravimetric data, three phases in the formation of this volcanic alignment can be identified: (i) a major magmatic intrusion in the early Pliocene associated with a NW-SE normal fault that formed during the opening of the Pantelleria graben, leading to the uplift and deformation of the host sedimentary rocks; (ii) a late Pliocene-Quaternary tectono-magmatic quiescent phase; and (iii) a renewed magma intrusion through fissures or cracks that led to the formation of the volcanoes in the late Quaternary. This process was not able to cause significant extension and only limited volcanism, which is why the "Tetide volcanic cluster" is interpreted as the morphological expression of a failed rift. [ABSTRACT FROM AUTHOR]

This paper presents the results of the interpretation of a set of high‐resolution seismic lines integrated with multibeam echosounder data acquired in a coastal area in the Northern Adriatic Sea. The aim of the study was to reconstruct the stratigraphic evolution of a late Quaternary sedimentary succession offshore the town of Bibione, North‐Eastern Italy, by recognising the key unconformities, identifying the main depositional units, dating them and reconstructing the depositional environments in relation to relative sea‐level variations. Specifically, four sedimentary units, separated by erosional unconformities associated with the development of deep channels, were identified and dated based on literature information. By interpreting the seismic data, sedimentary dynamics were reconstructed and palaeoenvironments identified. The lower unit corresponds to a paludal environment, showing abundant gas seeps and accumulations (bright spots); the two intermediate units correspond to fluvial deposits, filling the deep incisions that characterise the bounding surfaces. Finally, the shallowest unit, bounded by a wave‐ravinement surface incised by tidal currents, corresponds to the Holocenic progradation of the coastal wedge. In addition, several vertical gas chimneys were identified, ranging in width from a few metres to 20–30 m. These were present in all units, often reaching the sea floor. Finally, elongated mounds, about 300 m wide, at the sea floor were recognised. The bathymetric and seismic characteristics of these elongated bodies and their relationship to adjacent sedimentary bodies suggest that they are probably methane‐derived carbonate formations known as 'Trezze' or 'Tegnùe'. These names recall the fact that the trawls of the local fishermen were often hindered ('tegnù' in the Venetian language) or even cut off by these formations. [ABSTRACT FROM AUTHOR]

Engineers need to know properties of shallow marine sediments to build piers, pipelines and even offshore windfarms. We present a method for estimating the density, P velocity and thickness of these sediments. The traveltime inversion of primary and multiple reflections enables their semiquantitative estimation in marine surveys when using a minimal acquisition system such as a monochannel Boomer. Picking errors, ambient noise and interfering events lead to significant errors in the estimates. Similar, albeit milder, instabilities occur when inverting the signal amplitudes to determine the reflectivity of the layer interfaces. In this paper, we introduce a coupling between the separate inversion of amplitudes and traveltimes to obtain a better Earth model. The P velocity shows up in two stable terms provided by the separate inversions: the acoustic impedance of shallow sediments (through the amplitudes) and the transit time across the sediment layer (through the traveltimes). We couple the two inversion engines by imposing a smoothness condition on velocity and density and thickness of the layer while keeping the impedance and traveltime constant. We thus exploit the ambiguity of the solution to introduce geological criteria and reduce the noise contribution. We validated the proposed method with synthetic and real data. [ABSTRACT FROM AUTHOR]

The ancient Greek colony of Selinunte, with its acropolis on a promontory on the south-western coast of Sicily, is flanked by two valleys where two modest rivers flow today: the Modione to the west and the Cottone to the east. Archaeological reconstructions, historical documents from various sources, and recent remote sensing surveys indicate two important bays corresponding to the ancient mouths of these two rivers, now completely covered by a thick layer of sediments. It is believed that the ports of the colony were located in these bays, although the remains of these ports are still sparse and contradictory. Here we present a multibeam bathymetric map of part of the marine area immediately off Selinunte and a series of high-resolution seismic profiles acquired parallel to the coastline. They show the geometries and stratigraphic context of the two buried river valleys offshore, from which information about the palaeoenvironmental setting and evolution of the landscape can be derived and which may be used in adequately guiding future archaeological excavation programs. [ABSTRACT FROM AUTHOR]

Acquiring seismic data with multichannel, multiple‐streamer and even multi‐componentsystems at sea provides excellent images of the Earth. However, the cost and complexity of operations prevent their use in busy areas such as ports or in sensitive environments such as lagoons. In the latter cases, mono‐channel Chirp or Boomer systems are the most viable instruments for marine surveys. The lack of multiple offsets prevents the use of standard tools for amplitude‐versus‐offset and velocity analysis, which are necessary for the lithological characterization of rocks, especially for the shallow sediments in offshore engineering. In this paper, we present a few recent techniques that exploit the traveltime and amplitude of multiple reflections to compensate for the offset limitation, including a new algorithm for the joint tomographic inversion of direct arrivals, primaries and multiples. We have developed a cost‐effective workflow for mono‐channel surveys based on a data‐driven, physically consistent philosophy that attempts to approximately extract lithological parameters, such as P velocity, anelastic absorption, acoustic impedance and even density. We applied the proposed workflow to a real field experiment and obtained a semi‐quantitative estimate for shallow sediments that can be used by offshore engineers. [ABSTRACT FROM AUTHOR]

The lithological characterization of the seafloor is key information for offshore engineering, especially when it comes to pier and platform design. Undetected shallow gas pockets may cause the collapse of heavy platforms for hydrocarbon production. Unconsolidated sediments are not ideal for the basement of wind farms for electric power production. Drilling and coring can be used for local sampling, but continuous profiles or even areal coverage are far more preferable. High-resolution seismic profiles are successfully used when ports are not too busy, but otherwise, single-channel systems must be used. We show in this paper that even these simpler systems can be used to estimate parameters such as the acoustic impedance of shallow sediments directly beneath the seafloor. We exploit the amplitude decay of the multiple reflections between the seafloor and the surface, which does not depend on the source energy. If the offset between source and receiver is not too small, we can estimate the shallow P velocity and, via acoustic impedance, also the rock density. [ABSTRACT FROM AUTHOR]

The Sciacca basin extends in the southwestern part of Sicily and hosts an important geothermal field (the Sciacca Geothermal Field) characterized by hot springs containing mantle gasses. Newly acquired high-resolution seismic profiles (Boomer data) integrated with a multichannel seismic reflection profile in close proximity to the Sciacca Geothermal Field have documented the presence of numerous active and shallow fluid-related features (pipes, bright spots, buried and outcropping mud volcanoes, zones of acoustic blanking, and seafloor fluid seeps) in the nearshore sector between Capo San Marco and Sciacca (NW Sicilian Channel) and revealed its deep tectonic structure. The Sciacca Geothermal Field and the diffuse submarine fluid-related features probably form a single onshore–offshore field covering an area of at least 70 km2. This field has developed in a tectonically active zone dominated by a left-lateral transpressive regime associated with the lithospheric, NNE-striking Sciacca Fault System. This structure probably favored the rising of magma and fluids from the mantle in the offshore area, leading to the formation of a geothermal resource hosted in the Triassic carbonate succession that outcrops onshore at Monte San Calogero. This field has been active since the lower Pleistocene, when fluid emissions were likely greater than today and were associated with greater tectonic activity along the Sciacca Fault System. [ABSTRACT FROM AUTHOR]

In Tierra del Fuego, the Magallanes‐Fagnano Fault System (MFFS) accommodates a significant portion of the relative motion between the South America and Scotia plates. However, it remains unclear whether some of the deformation is partitioned southwards, along the Beagle Channel Fault System (BCFS). In this paper, high‐resolution seismic reflection profiles were used to identify fault‐related ruptures in the submerged Quaternary sediments of the Beagle Channel. Some faults reach the seafloor, affecting marine sediments, indicating they are Holocene in age. The correlation with outcrop data and lineaments mapped onshore suggests the post‐glacial reactivation of two structures: the E‐W striking BCFS and the NW‐SE‐trending Lapataia Fault Zone (LFZ). Whereas the BCFS displays along‐strike variation in throw, the LFZ shows significant normal displacements. These results imply that deformation occurs in a wider and more complex manner than previously thought and highlight the need for a thorough hazard assessment of the area. [ABSTRACT FROM AUTHOR]

Conventional multichannel surveys provide good images in 2D and 3D of the Earth in depth, which are successfully used for the oil and gas industries. However, their cost and environmental impact make them rarely affordable for engineering applications, especially for offshore infrastructures. In this case, monochannel systems, such as Boomers, having cables that are a few-meters long, provide time-domain images that are useful but miss relevant lithological information for engineers, such as the P-wave velocity of shallow layers. In this paper, we present a tomographic approach that exploits multiple reflections, in addition to primaries and direct arrivals, which work for monochannel surveys with a short offset. It can detect lateral variations of velocity and thickness of the first layer under the sea floor. Two complementary algorithms are compared: a pure tomographic inversion, and a tuning exploiting the classical Dix formula; the first one is more precise, while the second is more robust with respect to noise. A two-step inversion with incidence-angle parametrization performs slightly better than a single-step algorithm based on the direct traveltime inversion. We validate the method by synthetic and real data examples. [ABSTRACT FROM AUTHOR]

Featured Application: The presented method allows characterizing the seafloor P velocity for offshore engineering with a minimal impact in busy or environmentally fragile areas. The shallow P velocity provides relevant information for offshore engineers, in planning pipelines, piers, and platforms. Standard multichannel surveys trailing long cables provide good estimates but may require stopping other ongoing operations or may affect the environment. Monochannel surveys by Boomer systems involve a very short cable, so those drawbacks are minimized; however, this comes at the cost of loss of information for estimating the P velocity of shallow layers. In this paper, we present a new method exploiting multiple reflections for characterizing the seafloor. After validation of the algorithm by a synthetic example, we tested this approach in a marine survey acquired by a Boomer system at the Gulf of Trieste (Italy). [ABSTRACT FROM AUTHOR]

The increasing demand for freshwater requires the identification of additional and less-conventional water resources. Amongst these, offshore freshwater systems have been investigated in different parts of the world to provide new opportunities to face increasing water requests. Here we focus on the north-eastern Adriatic Sea, where offshore aquifers could be present as a continuation of onshore ones. Geophysical data, in particular offshore seismic data, and onshore and offshore well data, are interpreted and integrated to characterise the hydrogeological setting via the interpretation of seismo-stratigraphic sequences. We focus our attention on two areas located in the proximity of the Tagliamento and Isonzo deltas. Well and seismic data indicate that the Quaternary sediments, that extend from onshore to offshore areas, are the most promising from an offshore freshwater resources point of view, while the several kilometres thick pre-Quaternary carbonate and terrigenous sequences likely host mainly salty waters. [ABSTRACT FROM AUTHOR]

Lago Argentino hosts a series of calving glaciers originating from the Southern Patagonian Icefield, the largest temperate ice cap of the southern hemisphere. Brazo Rico and Brazo Sur are two basins located in the southern part of Lago Argentino, where a series of high-resolution seismic profiles have allowed reconstruction of its depositional setting and sedimentary architecture, and to produce the following maps: top of the acoustic basement, top of the glacial sequence, and thickness of the glacio-lacustrine deposits. Data reveal the role of basement highs in the complex dynamic behavior of the two main glaciers, Perito Moreno and Frías glaciers, which fluctuated along Brazo Rico and Brazo Sur since the end of the Last Glacial Maximum. Their advances and retreats are testified by the presence of several moraine fronts buried beneath a generally undisturbed, glacio-lacustrine and lacustrine sequence, which records the depositional history of the southern arms of Lago Argentino. [ABSTRACT FROM AUTHOR]

Lago Argentino hosts various calving glaciers, among them the famous Perito Moreno. Whereas the onland late Pleistocene–Holocene glacial history is rather well constrained, the submerged glacier-related features were until now undisclosed. Here we present a series of high-resolution seismic profiles revealing moraine bodies associated with the late-glacial glacier dynamics and the first bathymetric map of the Brazo Rico and Brazo Sur, the two southern arms of Lago Argentino. At the eastern termination of Brazo Rico, we identified at the lake floor the submerged expression of the Puerto Bandera 3 moraine mapped onshore, which represents the oldest event (12,660 ± 70 cal yr BP oldest minimum age) recognized in this lake arm, and seven other younger events expressed by a series of terminal and recessional moraines. Along the Brazo Sur, few moraine bodies have been imaged by seismic data. Here, the youngest temporal constraint comes from the Frías moraine (ca. 6000 cal yr BP), which closes off the southern end of the Brazo Sur. At the confluence of the two arms, the Perito Moreno and the former Frías glacier merged and flowed toward east during their late-glacial maximum advance (i.e., Puerto Bandera 1 moraine). The subaqueous evidence of moraine bodies testifies to the occurrence of previously undocumented pulses of the Perito Moreno and former Frías glaciers within the general phase of late Pleistocene–Holocene regression. [ABSTRACT FROM AUTHOR]

The outer Fuegian fold and thrust belt is the deformed sector of the Austral-Magallanes Basin, which underwent a contractional phase since the Late Cretaceous and a strike-slip phase during the Neogene. The area hosts two Neogene basins (Yehuin and Chepelmut) which have been mainly developed by the influence of wrench deformation, and were subsequently modified by glacial activity of the Ewan and Fuego glacier lobes of the Fagnano palaeoglacier. Geophysical surveys using Electrical Resistivity Tomography, onland shallow seismic surveys, and magnetometry, have been combined with outcrop analysis and deep seismic lines to recognize both shallow and intermediate deep structures related to the lacustrine basins. Four sets of faults with different deformation history were involved in the basin genesis. Comparison with the Deseado Fault Zone indicates similarities of the structural features between the two zones. The stress field interpreted as responsible for the origin of the studied basins is analogous to the one in the Deseado valley, located in the western Tierra del Fuego. Therefore, a transcurrent fault zone, here named Yehuin–Chepelmut Fault Zone, is proposed as part of the diffuse boundary between South America and Scotia plates. [ABSTRACT FROM AUTHOR]

Lago Roca/Acigami is a "fjord‐type" lake located in the southernmost part of South America, in the proximity of the Beagle Channel. A high‐resolution seismic survey was carried out to analyse the seismic stratigraphy of the lake and to shed some light on the post‐Last Glacial Maximum history of the area. Six seismic units were recognised, and their nature and depositional context were interpreted using seismic stratigraphy and acoustic facies analysis. A buried large ridge was identified within the glacial unit (SU1), interpreted as a frontal moraine that indicates a stabilisation phase. After retreat of the glacier from the basin, the trough was flooded by meltwater and a lake developed (SU2). The seismic facies, from bottom to top, depict a transition from ice‐contact (SU2; SU3) to ice‐distal proglacial conditions (SU4). A thick draping unit (SU5) marks a marine transgressive event and the instauration of a fjord environment in the basin. The marine transgression was a rapid event preceded by a fall in the lake level that caused an erosional unconformity. During the fjord phase the sedimentation remained controlled by meltwater discharge. Sea level fall, and subsequent disconnection from the Beagle Channel was accompanied by a progradation of the glaciofluvial deltaic sediments and the occurrence of several mass‐wasting deposits (SU6). © 2019 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Port of Trieste is an international hub for land and sea trade with the dynamic markets of central and eastern Europe. Thanks to its deep natural draft (about 18 m), the modern high‐capacity vessels can moor to the piers. In view of the foreseen increase in maritime traffic, this harbour is undergoing modernization in order to improve the commercial traffic capability. In this expansion plan, the container Trieste Marine Terminal, Pier VII, is seeking an extension by about 200 m. In support of this feasibility study, multidisciplinary data acquisition was conducted in order to characterize the seabed, the sub‐bottom sediments and the bedrock (flysch formation) in front of the Trieste Marine Terminal. The acquisition of high‐resolution swath bathymetry, side‐scan sonar and magnetometer data allowed a detailed analysis of the seabed conditions from an environmental and safety perspective. High‐resolution seismic reflection data enabled us to characterize the Plio‐Quaternary soft sediments and the underlying bedrock. A static underwater refraction survey was performed using hydrophone array deployed on the sea bottom to obtain seismic velocities and to achieve a reliable time‐to‐depth conversion of reflection seismic data by first‐arrival tomographic inversion. In addition to geophysical investigations, 11 offshore boreholes were drilled for detailed logging. In situ standard penetration tests were performed on core samples with the use of a pocket penetrometer and pocket vane in order to obtain uniaxial compressive strength, undrained shear strength and undrained cohesion values, and assess the cohesive soils. During drilling, 17 undisturbed samples and 12 semi‐disturbed samples were extracted to perform laboratory tests for the identification of the principal geotechnical parameters. The goal was to obtain a reliable geological/geotechnical model in front of the Trieste Marine Terminal – from the seabed to the bedrock. Below the seafloor, a sequence of about 20–30 m thickness, containing Plio‐Quaternary soft sediments, overlies the flysch, which locally presents alteration with rocks of reduced quality. The geophysical–geotechnical integrated approach allowed us to identify and map the top of the bedrock and provided valuable information for planning the pier extension project. [ABSTRACT FROM AUTHOR]

We present a high-resolution swath bathymetric and backscatter map of the entire sector of the Marine Reserve Area (MRA) of the Asinara Island, along with a geological and sediment thickness map derived from the interpretation of a large set of high-resolution seismic profiles, and an airborne-derived hyperspectral image of the Asinara Island. Acquired data show that most of the eastern marine sector of the Asinara Island is characterized by quite gentle bathymetric gradients, whereas the western coastline appears to be very indented, with an articulated and rough morphology of the seafloor, which deepens sharply towards the open sea. The maps presented in this study at the 1:50.000 scale do not only provide the first, high-resolution bathymetry of the MRA of the Asinara Island but also may furnish the base for the creation of a benthic habitat map and a more comprehensive maritime spatial planning of this protected area. [ABSTRACT FROM AUTHOR]

For the first time a comprehensive investigation has been carried out to quantify the possible effects of dredging a navigable canal on the hydrogeological system underlying a coastal lagoon. The study is focused on the Venice Lagoon, Italy, where the port authority is planning to open a new 10m deep and 3 km long canal to connect the city passenger terminal to the central lagoon inlet, thus avoiding the passage of large cruise ships through the historic center of Venice. A modeling study has been developed to evaluate the short (minutes), medium (months), and long (decades) term processes of water and pollutant exchange between the shallow aquifer system and the lagoon, possibly enhanced by the canal excavation, and ship wakes. An in-depth characterization of the lagoon subsurface along the channel has supported the numerical modeling. Piezometer and sea level records, geophysical acquisitions, laboratory analyses of groundwater and sediment samples (chemical analyses and ecotoxicity testing), and the outcome of 3-D hydrodynamic and computational fluid dynamic (CFD) models have been used to set up and calibrate the subsurface multi-model approach. The numerical outcomes allow us to quantify the groundwater volume and estimate the mass of anthropogenic contaminants (As, Cd, Cu, Cr, Hg, Pb, Se) likely leaked from the nearby industrial area over the past decades, and released into the lagoon from the canal bed by the action of depression waves generated by ships. Moreover, the model outcomes help to understand the effect of the hydrogeological layering on the propagation of the tidal fluctuation and salt concentration into the shallow brackish aquifers underlying the lagoon bottom. [ABSTRACT FROM AUTHOR]

The Sicilian Channel is a broad and shallow shelf which is geologically part of the African Plate. Its NW sector (the Adventure Plateau), where water depths rarely exceed 100 m, is punctuated by several kilometre-sized morphological highs. These elevations, formed by both sedimentary and volcanic rocks, emerged around middle Holocene time or earlier when they constituted a large archipelago. High-resolution single-channel and multichannel seismic reflection profiles, along with stratigraphic and lithological information derived from exploration wells and rock samplings, are analysed to derive the shallow and deep structural setting of these banks and identify their geological nature. The sedimentary banks (Talbot, Ante-Talbot, Panope, Nereo and Pantelleria Vecchia), presently located at water depths 8–40 m, are composed of Miocene rocks severely deformed by a late Miocene compressional phase which produced the external sector of the Sicilian–Maghrebian thrust belt. Tortonian-aged rock samples from the Pantelleria Vecchia Bank represent patch reefs that have mostly formed on structural highs. Sedimentary analogies suggest that other sedimentary banks of the Adventure Plateau may have the same origin. Galatea, Anfitrite and Tetide represent submarine volcanic edifices emplaced on major extensional faults formed during early Pliocene – Quaternary continental rifting of the Sicilian Channel. The present-day morphology of the banks is the result of repeated phases of subaerial exposure and drowning, especially since the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The Holocene succession located in the central part of the Venice Lagoon has been investigated by means of high-resolution seismic and core data, which document a full back-barrier depositional environment developed during the last 6 kyr. The studied succession, 4.5–23 m thick, consists of three seismic units bounded at the base by stratal surfaces marked by deep tidal channel incisions, recording main changes in the lagoon hydrodynamics as well as reorganizations of the tidal channel network. The recognized depositional and erosional phases in the lagoon deposits can be linked to both large-scale factors related to the Holocene sea-level rise and local factors in part due to the human impact. In particular, the lower unit is interpreted as the transgressive systems tracts of the Holocene sequence, initially characterized by the accumulation within small estuarine channels incised during the previous phase of subaerial exposure, whereas the upper units are interpreted as the highstand systems tracts, typified by the persistence of the lagoonal environment. The higher stratal surface records a hydrodynamic change related to a local transgression affecting a deltaic area placed just to the south, probably at least in part aided by human interventions. The Holocene succession accumulated in the central part of the Venice Lagoon testifies that the development of stratal surfaces in back-barrier settings, persisting during both transgressive and highstand conditions, may exhibit differences with respect to that predicted by current sequence stratigraphic models, and therefore, it is useful to improve the knowledge of these systems. [ABSTRACT FROM AUTHOR]

Acquiring large amounts of data in very shallow waters of the immediate subtidal zone using a multichannel technique is unaffordable because moveout correction and a standard stacking procedure are required. The conventional inline longitudinal deployment of source and streamer leads to a phase difference along the hydrophone array for nonvertical arrivals. The array in this system is hard wired, so these please differences cannot be accounted for and the summed output is attenuated as a result. We propose a transverse configuration, whereby the variation in phase along the array is smaller. The summed output improves because pairs of hydrophones with equivalent absolute offset are stacked in phase as a result of the symmetric configuration; however, all of the hydrophones are out of phase in the conventional geometry. Even at depths of 40 m, a better image is obtained. The technique has been used during surveys in the Venice lagoon, where the water depth ranges from 40 cm to 2 m. [ABSTRACT FROM AUTHOR]

The processing of Chirp data is limited by the usual recording of the signal envelope, which enhances its immediate visibility but prevents applying methods based on wave equations. This is normally not the case for Boomer data. However, both systems are monochannel instruments, which cannot estimate properly the propagation velocity of the signal in the rocks. In this paper, we present two theorems: the first one links the Chirp or Boomer source spectrum with an expected amplitude decay curve; the second one defines conditions for the deconvolution stability of the enveloped Boomer signal when the full waveform of the source signal is known. In this way, we can jointly process and integrate heterogeneous surveys including both data types. We validated the proposed algorithms by applying them to synthetic and real data. The presented tools can improve the image resolution and the characterization of geological formations in marine surveys by reflectivity anomalies, which are distorted by standard equalization methods. [ABSTRACT FROM AUTHOR]

Edisto Inlet, located along the northern Victoria Land coast, is a small fjord about 15 km long and 4 km wide, carved by glacial processes and separated by a sill from the larger Moubray Bay.The bathymetry shows a reversed slope and ranges from 670 m in the innermost sector of the bay to 100 m near the entrance of the bay.The Edisto Inlet is seldom accessible due the presence of persistent sea ice but in 2017 during the PNRA (Programma Nazionale delle Ricerche in Antartide) OGS Explora expedition, exceptional sea-ice free conditions allowed for the first time the acquisition of a wealth of data (including sub-bottom chirp profiles, multibeam swath bathymetry, Acoustic Doppler Current Profiler measurements as well as two gravity cores) inside the fjord.The geophysical dataset combined with previous echo-sounding data collected in the outer sector of the fjord reveal the presence of sediment drifts that hypothetically formed under the influence of bottom currents. The sediment drifts are characterized by a very high sedimentation rate and are potential excellent paleoclimatic archives. Paleoclimate records are crucial for understanding current changes taking place in the Antarctica; However, paleoclimate and oceanographic reconstructions, especially from the Antarctic fjords, as well as the circulation and processes impacting their exchange with the shelf and wider ocean, are scarce.Here we present the first report of the integrated analysis of all geophysical dataset aimed to understand relationship between the seabed morphology and present day velocity and direction of the currents. Moreover, the evolution over the late deglaciation phase can be inferred by comparing the results with the stratigraphic information from existing sediment cores.The comparison of all data and observations with the numerical simulation of ocean dynamics, will permit to understand the climatic evolution of the fjord. Link with the climatic evolution of the Victoria Land coast and with other Antarctic sectors of the same area will allow to understand the interaction between East and West Antarctica. [ABSTRACT FROM AUTHOR]

Abstract: The southern portion of the Venice lagoon contains a relatively thick (up to 20m) Holocene sedimentary body that represents a detailed record of the formation and evolution of the lagoon. New very high-resolution (VHR) seismic profiles provided a detailed investigation on depositional geometries, internal bounding surfaces and stratal relationships. These informations, combined with core analysis, allowed the identification of large- to medium-scale sedimentary structures (e.g. dunes, point bars), the corresponding sedimentary environment, and of retrogradational and progradational trends. In addition, the availability of dense seismic network produced a 3D reconstruction of the southern lagoon and the recognition of the along-strike and dip variability of the stratal architecture. Three main seismic units (H1–H3), separated by key stratal surfaces (S1-S3), form the Holocene succession in the southern Venice lagoon. This succession is bounded at the base by the Pleistocene/Holocene boundary (the surface S1), which consists of a surface of subaerial exposure locally subjected to river incision. The lower part of the Holocene succession (up to 13m thick) consists of incised valley fills passing upward into lagoon and then shallow-marine sediments (Unit H1), and therefore shows a deepening-upward trend and a retrogradational stacking pattern. A prograding delta and adjacent shorelines, showing internal clinoforms downlapping onto the top of Unit H1 (the surface S2), form the middle part of the Holocene succession (Unit H2, up to 7.5m thick). Unit H2 is interpreted as a result of a regressive phase started about 6kyr BP and continued until recent time. The upper part of the Holocene succession (Unit H3) consists of lagoonal deposits, including tidal channel and tidal and subtidal flat sediments, that abruptly overlie Unit H2. Unit H3 is thought to represent a drowning of the area primarily due to human interventions that created rivers diversion and consequent delta abandonment during historical time. [Copyright &y& Elsevier]