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Papers by salvatore passaro

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

Chemistry and Ecology, Jul 2, 2020

In this study, we present the results of a very high-resolution bathymetric survey carried out of... more In this study, we present the results of a very high-resolution bathymetric survey carried out offshore the dismissed industrial site of Bagnoli (Pozzuoli Bay, Gulf of Naples). The bathymetric maps and the thematic representation produced, allowed for detailed characterisation of the seabed lineaments and features. Seafloor bedforms and morphological features can be observed at a very high resolution. Moreover, the potential pattern of sediment transport can be inferred from the seafloor bedforms observed in the central sector of the surveyed area. The new morphobathymetric map of Bagnoli-Coroglio offshore provides a valuable tool for stakeholders towards a comprehensive planning and management addressed to environmental revaluation and rehabilitation of this disused industrial area.

La geologia marina in Italia - Primo convegno dei geologi marini italiani, 2016

During the last decade, we have blended our individual skills to form a research group devoted to... more During the last decade, we have blended our individual skills to form a research group devoted to investigating active crustal deformation in areas adjacent to the coast of Southern Italy, with the aim to bridge the gap between the onshore and offshore realms. Our research is based on a multi-scale and multi-resolution approach that includes high-resolution seismics, coastal morpho-tectonics and structural geology, complemented by seismicity, Global Positioning System and InSAR. Need and opportunities of such an endeavor arise from the basic observation that, although most population centers lie close to the coastal areas, very little is known about active structures at the sea. However, hints of active deformation occurring offshore are offered by physical correlation with known or proposed onland seismogenic sources, macroseismic fields of historic events, tsunamis. The capability of our group stems from the long-term experience for most types of marine geological and geophysical surveys, and for structural-stratigraphic analysis of tectonically active areas. We regard the land-sea correlation issue as a key missing link that has hampered, so far, a sound interpretation of active structures in the submerged realm. Starting from this basis, we focused our attention on key sectors of the Southern peninsular Italy and Sicily where active tectonics has been inferred offshore, but detailed information on deformation structures is missing. The core dataset involves very high-resolution, single-channel (SCS) and multi-channel (MCS) data acquired with a series of seismic sources, including multi-tips Sparker array, to provide detailed images of the most recent (e.g. Middle-Late Pleistocene) activity of targeted structures. These data were supplemented by ultra high-res (CHIRP) seismics, and multibeam bathymetric data to get a snapshot of the current deformation close or at the sea-floor, as well as public (VIDEPI project) and unpublished MCS profiles. In addition to data acquired onboard oceanographic research vessels, we complement the dataset by using a Sparker System mounted onboard a trailer-transportable boat suitable to acquire for nearshore surveys. Using additional datasets (seismicity, structural analysis, InSar, GPS etc.), the ultimate goal is a parameterization of active structures (e. g. Ferranti et al., 2014, Barreca et al., 2014), and the calculation of accurate rates of vertical movements (e.g. Pepe et al., 2014), on the basis of case-histories from Calabria and Sicily

RENDICONTI ONLINE DELLA SOCIETÀ GEOLOGICA ITALIANA, Oct 1, 2015

Vesuvius, Campi Flegrei, and Campanian Volcanism, 2020

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

We present morphological and stratigraphic results coming from surveys acquired in a NNW-SSE tren... more We present morphological and stratigraphic results coming from surveys acquired in a NNW-SSE trending submarine depression (Marettimo Valley) located in the Egadi Islands (western Sicily offshore). In this area the seafloor is characterized by both depositional and erosional features generated under a variety of sedimentary processes. We identified two seismic facies units that are correlatable to: A) the progradation of shallow water (coastal to offshore) deposits during forced-regression sedimentary process, and B) contourite drifts emplaced by geostrophic currents through the Marettimo Valley. This unusual association of very shallow water contourites and shelf margin deposits originates, during middle-late Pleistocene glacio-eustatic cycles, from enhanced sedimentary dynamics establishing mutual interaction between progradational growth of the margin and bottom current deposition

IODP-Lo stato delle proposte di perforazione per l'area del Mediterraneo www.iodp-italia.cnr.

Estuarine, Coastal and Shelf Science, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Chemistry and Ecology, 2020

Bagnoli-Coroglio is a Site of National Interest (SNI) facing the Pozzuoli Bay that has been the p... more Bagnoli-Coroglio is a Site of National Interest (SNI) facing the Pozzuoli Bay that has been the place of an industrial activity for more than a century (1854-1985). The modern coastal geology of this area results from the recent evolution of an antecedent volcanic landscape that originated after a caldera collapse following the eruption of Neapolitan Yellow Tuff (NYT) of Campi Flegrei (15 ka). After the NYT eruption, a shallow marine depression formed within the caldera collapse area that underwent progressive filling-up, due to volcaniclastic sediment input from the caldera borders, within a semi-enclosed source-tosink system. The integrated interpretation of the Digital Terrain Model (DTM) of the Bagnoli-Coroglio area and the high resolution reflection seismic profiles acquired off the Pozzuoli Bay suggests that the present-day coastal plain of Bagnoli-Fuorigrotta and conterminous continental shelf represent the latest infilling phase of the annular depression (caldera 'collar') between the structural border of the NYT caldera and the inner caldera resurgent dome. The stratigraphic architecture and morpho-bathymetry of the Bagnoli inner shelf provide a record of the complex interplay between eustatic sea level changes, volcano-tectonic (ground/ seafloor) deformation, and supply of volcaniclastic sediments, with associated coastline shifts over the last millennia.

Scientific Reports, 2020

The dynamics of deep sea explosive eruptions, the dispersion of the pyroclasts, and how submarine... more The dynamics of deep sea explosive eruptions, the dispersion of the pyroclasts, and how submarine eruptions differ from the subaerial ones are still poorly known due to the limited access to sea environments. Here, we analyze two ash layers representative of the proximal and distal deposits of two submarine eruptions from a 500 to 800 m deep cones of the Marsili Seamount (Italy). Fall deposits occur at a distance of more than 1.5 km from the vent, while volcanoclastic flows are close to the flanks of the cone. Ash shows textures indicative of poor magma-water interaction and a gas-rich environment. X-ray microtomography data on ash morphology and bubbles, along with gas solubility and ash dispersion models suggest 200–400 m high eruptive columns and a sea current velocity <5 cm/s. In deep sea environments, Strombolian-like eruptions are similar to the subaerial ones provided that a gas cloud occurs around the vent.

Földtani Közlöny, 2019

Very high-resolution, single channel (IKB-Seistec™) reflection profiles acquired offshore the Nap... more Very high-resolution, single channel (IKB-Seistec™) reflection profiles acquired offshore the Napoli Bay, complemented with geological and geophysical data from the literature, provide unprecedented, superb seismic imaging of the Latest Pleistocene-Holocene stratigraphic architecture of the submerged sectors Campi Flegrei and Somma-Vesuvius volcanic districts. Seismic profiles were calibrated by gravity core data and document a range of depositional systems, volcanic structures and hydrothermal features that evolved after the onset of the Last Glacial Maximum (ca. 18 ka BP) over the continental shelf on the Campania coastal zone.Seistec profiles from the Pozzuoli Bay yield high-resolution images of the shallow structure of the collapse caldera-ring fault - resurgent dome system associated with the eruption of the Neapolitan Yellow Tuff (NYT) (ca 15 ka BP) and support a working hypothesis to assess the timing and the styles of deformation of the NYT resurgent structure throughout the...

Marine Geology, 2018

The occurrence of articulated seafloor morphology over continental shelf-upper slope environments... more The occurrence of articulated seafloor morphology over continental shelf-upper slope environments, may result in a significant change in the patterns and intensity of basin-scale thermohaline circulation during eustatic sealevel fluctuations. These changes may cause, in turn, erosion, deposition and/or transport of sediments at the seafloor, to form shallow-water contourite drifts. Here we investigate this process in the NW sector of the Gulf of Taranto (Ionian Sea) during and following the Last Glacial Maximum (LGM), by integrating multibeam bathymetric data, ultra-high resolution seismic-reflection data and gravity core data. Sea level fall caused subaerial exposure of the summit of the Amendolara Bank, forming a short-lived island off the eastern coast of Calabria, and also creating a narrow passageway between the island and the northern Calabria mainland. Integrated seismic-stratigraphic data show that Upper Quaternary shallow-water contourite drifts and associated erosional features locally formed both around the flanks of the Amendolara Bank (AMBK), and the continental shelf and upper slope off the Amendolara village. Contourite drifts are bounded at the bottom and at the top by two major unconformities, indicating that the formation of the sediments drifts occurred between the onset of the LGM and the GS-1/Younger Dryas event. The stratal architecture suggests the occurrence of various types of contourite deposits, mostly represented by: a) Axial and lateral channel-patch drifts, and channel-related drifts along the incision to the NE of the AMBK; b) Sheeted drifts along the northeastern slope of the AMBK; c) Elongated drifts along the continental shelf and upper slope off the coast of Amendolara village. Erosional features also developed on the southeastern flank of the AMBK, where the Levantine Intermediate Water flows from the central Ionian Sea towards the Gulf of Taranto, until the present-day. Both processes and timing responsible for erosion of the seafloor and the formation of sediment drifts in the Gulf of Taranto may be similar to that occurred in the Tyrrhenian margins during the Late Quaternary.

Global and Planetary Change, 2019

A multidisciplinary study, which includes micropaleontology, sedimentology and geochemistry, was ... more A multidisciplinary study, which includes micropaleontology, sedimentology and geochemistry, was carried out on the TEA-C6 core, raised in the Gulf of Taranto (north-western Ionian Sea). The chronological framework was yielded by tephrostratigraphy combined with ecostratigraphy and AMS 14 C dating. New results allowed surface and bottom conditions in the Gulf of Taranto during the last 15 ky to be reconstructed, thus providing a detailed and age-constrained paleoclimate and paleocological record for this sector of the Mediterranean Sea. The quantitative record of past sea surface temperatures (SST) was obtained by means of Compositional Data Analysis (CoDA) methods applied to planktonic foraminifera assemblages. High-resolution analyses allowed the Sapropel S1 event to be characterised at centennial-scale resolution. The main interval of the sapropel S1, here dated between 10.2 cal ka and 7.8 cal ka, is preceded and followed by transition phases spanning several centuries and prevailing anoxic bottom conditions are punctuated by several episodes of partial oxygen recovery. The S1a interval corresponds to high summer SST, whereas an SST drop of about 2.5°took place towards the end of the S1b interval. New tephrochronological data record the signature of eruptive events from Italian volcanoes which were not documented on land up to date.

Geophysical Research Letters, 2016

We analyzed new magnetic, bathymetric, and seismic data acquired in the offshore sector of Somma-... more We analyzed new magnetic, bathymetric, and seismic data acquired in the offshore sector of Somma-Vesuvius volcano (Italy). We detected a group of high-intensity, short wavelength magnetic anomalies corresponding to partly buried volcanic dome-like structures located by seismic data. The magnetic anomalies are aligned along a NW-SE strike that is the preferential orientation of an eruptive fracture of the pre-19 ka activity of Vesuvius. Four cones emplaced after the Last Glacial Maximum (19 ka), whereas a fifth one emplaced more recently suggesting a rejuvenation of the eruptive system offshore the volcano in historical times. We also identified a NE-SW elongated magnetic anomaly consistent with a dike-like body associated to an on-land tectonic structure that was active in recent times at Vesuvius. A delta-like area with diffuse low-intensity magnetic anomalies reflects the seaward fronts of lava flows that entered the sea mainly during the Middle Ages.

Natural Hazards, 2016

The Gulf of Patti and its onshore sector represents one of the most seismically active region of ... more The Gulf of Patti and its onshore sector represents one of the most seismically active region of the Italian Peninsula. Over the period 1984-2014, about 1800 earthquakes with small-to-moderate magnitude and a maximum hypocentral depth of 40 km occurred in this area. Historical catalogues reveal that the same area was affected by several strong earthquakes such as the Mw=6.1 event in April 1978 and the Mw=6.2 one in March 1786 which have caused severe damages in the surrounding localities. The main seismo-tectonic feature affecting this area is represented by a NNW-SSE trending right-lateral strike-slip fault system called "Aeolian-Tindari-Letojanni" (ATLFS) which has been interpreted as a lithospheric transfer zone extending from the Aeolian Islands to the Ionian coast of Sicily. Although the large-scale role of the ATLFS is widely accepted, several issues about its structural architecture (i.e., distribution, attitude, and slip of fault segments) and the active deformation pattern are poorly constrained, particularly in the offshore. An integrated analysis of field structural geology with marine geophysical and seismological data, has allowed to better understand the structural fabric of the ATLFS which, in the study area, is expressed by two major NW-SE trending, en-echelon arranged fault segments. Minor NNE-SSW oriented extensional structures mainly occur in the overlap region between major faults, forming a dilatational stepover. Most faults display evidence of active deformation and appear to control the main morpho-bathymetric features. This aspect, together with diffused continental slope instability, must be considered for the revaluation of the seismic and geomorphological hazard of this sector of southern Tyrrhenian Sea.

Global and Planetary Change, 2015

Abstract The volcanism of back-arc basins resembles that of oceanic spreading centers, rifts, and... more Abstract The volcanism of back-arc basins resembles that of oceanic spreading centers, rifts, and, in vanishing stages, extensional arcs, depending on the amount and rate of the dynamic processes associated to the subduction. Marsili Seamount (MS) represents the axial ridge of the Southern Tyrrhenian Sea back-arc basin, which is connected to the slab roll-backing processes affecting the Calabrian Arc (Italy). The Southern Tyrrhenian Sea back-arc is characterized by a significant decline in the spreading rate with time (2.8–3.1 mm/a to less than 1.8 mm/a in the last 0.78–1 Ma). MS develops between about 1 Ma and 3 ka and mainly consists of lava flows erupted from central and fissural vents. The MS products belong to the calcalkaline association and range in composition from basalts to trachytes. We present new stratigraphic, geochronological, and geochemical data (glass shards and minerals) of tephra from a 2.35 m long gravity core (Marsili1 core) recovered on MS at 943 m b.s.l. We recognize five tephras [M1 (top of the core) to M5 (bottom)] represented by poorly to highly vesiculated ashes. The lowermost tephra M5 emplaced between ca. 7 and 26 ka B.P.; it represents the less evolved distal counterpart of the Unit D related to the Biancavilla–Montalto products of Mount Etna (Sicily). The M1 to M4 tephras emplaced between 2.1 and 7.2 ka B.P. and are related to strombolian-like submarine eruptions of NNE–SSW aligned MS vents. The composition of the M1–M4 glasses ranges from basaltic trachyandesites to andesites and trachytes. The M1 to M4 magmas mainly originated by crystal fractionation from a heterogeneous mantle source with varying LILE enrichments by subduction-related fluids. The degree of evolution of the MS magmas increases with decreasing time. The formation of vertically stacked magma storage zones at the crust/mantle interface and within MS is related to the vanishing Southern Tyrrhenian Sea opening, which implies the rapid (

8th Congress of the Balkan Geophysical Society, 2015

Modern technologies in the field of marine geophysical surveys allow us to obtain accurate and de... more Modern technologies in the field of marine geophysical surveys allow us to obtain accurate and detailed information on the characteristics of the seabed and the marine substrate. In this paper we present a new magnetic high-resolution map of the Somma-Vesuvius offshore (Gulf of Naples, Southern Italy) depicting some main volcanological and tectonic structures of the area. The analysis of a new marine magnetic dataset, acquired during the oceanographic survey “SAFE_2014”, highlighted the presence of a group of NNW-SSE trending anomalies. This magnetic alignment suggests a volcano-structural correlation with the major faults in the area. We was also identified a NE-SW trend of magnetic anomalies, which may be associated with a tectonic structures interpreted as a magma preferential path of Somma-Vesuvius. Furthermore morphological irregularities of the seabed, shown by new morpho-bathymetric data, were found in correspondence with some of the main magnetic anomalies of Vesuvius offshore. This confirms the hypothesis of a possible connection between the Vesuvian volcanic structures and the tectonic regime of the Gulf of Naples, which controls this region since the Neogene-Quaternary.