Nevio Zitellini

• Italian National Research Council

Mantle processes control plate tectonics and exert an influence on biogeochemical cycles. However, the proportion of mantle sampled in-situ is minimal, as it is buried beneath igneous crust and sediments. Here we report the lithological characteristics of two mantle sections from an embryonic ocean drilled by the International Ocean Discovery Progr...

Seamounts are spectacular bathymetric features common within volcanic and tectonically active continental margins. During their lifecycles, they evolve through stages of construction and destruction. The latter are marked by variable magnitude flank collapses that often interrupt the evolution of seamounts and constitute a major source of hazard. T...

The Tyrrhenian Sea in the central Mediterranean Sea was form by Neogene slab roll-back of the retreating Ionian slab about 6 to 2 Myr ago. Yet, little is known about the structure of its southern margin off Sicily as well as back-arc extension and spreading in the southern Tyrrhenian Sea to the north of Sicily. The Sicilian margin is generally clas...

The southern part of Tyrrhenian back-arc basin (NW Sicily), formed due to the rifting and spreading processes in back-arc setting, is currently undergoing contractional tectonics. The analysis of seismic reflection profiles integrated with bathymetry, magnetic data and seismicity allowed us to map a widespread contractional tectonics structures, su...

Synchronous interaction between bottom currents and turbidity currents has been reported often in channel-levée systems where the thickness of the turbidity currents exceeds that of the levées. Such interplay between along-slope and down-slope sedimentary processes is one of the mechanisms by which 'mixed turbidite-contourite systems' can originate...

The formation of Cenozoic mountain belts in the Mediterranean realm was preceded by tens of millions of years of subduction, forming volcanic arcs, and frontal contractional systems. In addition, subduction usually involves slab rollback and formation of oceanic backarcs. Although such structure must have influenced the orogeny of Mediterranean mou...

We present a new tectonic map focused upon the extensional style accompanying the formation of the Tyrrhenian back‐arc basin. Our basin‐wide analysis synthetizes the interpretation of vintage multichannel and single channel seismic profiles, integrated with modern seismic images and P‐wave velocity models, and with high resolution morpho‐bathymetri...

The Tyrrhenian Basin is a region created by Neogene extensional tectonics related to slab rollback of the east-southeast–migrating Apennine subduction system, commonly believed to be actively underthrusting the Calabrian arc. A compilation of >12,000 km of multichannel seismic profiles, much of them recently collected or reprocessed, provided close...

The Alpine orogeny is well recorded onshore and offshore by tectonic inversion of the Mesozoic rift basins. Large scale linear seamounts (more than 250 km long and with up to 5 km of uplift) involving oceanic and continental lithosphere were carried on top of thrusts, such as the Gorringe seamount and the Estremadura Spur in the SouthWest and West...

We use seismic oceanography to document and analyze oceanic thermohaline finestructure across the Tyrrhenian Sea. Multichannel seismic (MCS) reflection data were acquired during the MEDiterranean OCcidental survey in April-May 2010. We deployed along-track expendable bathythermograph probes simultaneous with MCS acquisition. At nearby locations we...

The Gulf of Cadiz seismicity is characterized by persistent low to intermediate magnitude earthquakes, occasionally punctuated by high magnitude events such as the M ~ 8.7 1755 Great Lisbon earthquake and the M = 7.9 event of February 28th, 1969. Micro-seismicity was recorded during 11 months by a temporary network of 25 ocean bottom seismometers (...

High-resolution acoustic and seismic data acquired 100 km offshore Cape São Vicente, image with unprecedented detail one of the largest active reverse faults of the SW Iberian Margin, the Horseshoe Fault (HF). The HF region is an area seismogenically active, source of the largest magnitude instrumental and historical earthquake (Mw > 6) occurred in...

The structural complexity of back-arc basins is related to the evolution of the associated subduction system. Here we present an integrated geophysical and geological study that constrains the 3D spatial variability of magmatic activity along the Tyrrhenian back-arc basin. We use wide-angle seismic and gravity data, acquired in 2010 within the MEDO...

Submarine mass failures represent one of the most significant marine geo-hazards. Their importance as a major contributor to tsunami generation and hazard has been recognized over the last 20–30 years. This study investigates a newly mapped submarine landslide, the South Hirondelle Landslide (SHL), and its potential to generate a tsunami and to thr...

The Tyrrhenian basin opened in the Neogene following the E–SE retreat of the Appenines–Calabrian subduction system and the subsequent back-arc extension of an orogenic crust. The resultant crustal structure includes a complex distribution of continental, back-arc magmatism, and mantle-exhumation domains. A clear example of this complex structure is...

S U M M A R Y Geophysical data from the MEDOC experiment across the Northern Tyrrhenian backarc basin has mapped a failed rift during backarc extension of cratonic Variscan lithosphere. In contrast, data across the Central Tyrrhenian have revealed the presence of magmatic accretion followed by mantle exhumation after continental breakup. Here we an...

It It is well documented that, in the past, catastrophic earthquakes and tsunamis affected the area as described in the historical records from the countries bordering the Gulf of Cadiz: Portugal, Spain and Morocco (cf. Baptista and Miranda, 2009; Figure 6.1). The main mechanism behind geohazard generation in this area is the interplate deformation...

[1] Extension of the continental lithosphere leads to the formation of rift basins, or rifted continental margins if break-up occurs. Seismic investigations have repeatedly shown that conjugate margins have asymmetric tectonic structures, and different amount of extension and crustal thinning. Here, we compare two coincident wide-angle and multicha...

We present a new classification of geological domains at the Africa-Eurasia plate boundary off SW Iberia, together with a regional geodynamic reconstruction spanning from the Mesozoic extension to the Neogene-to-present-day convergence. It is based on seismic velocity and density models along a new transect running from the Horseshoe to the Seine a...

1] In this work we investigate the crustal and tectonic structures of the Central Tyrrhenian back-arc basin combining refraction and wide-angle reflection seismic (WAS), gravity, and multichannel seismic (MCS) reflection data, acquired during the MEDOC (MEDiterráneo OCcidental)-2010 survey along a transect crossing the entire basin from Sardinia to...

In the framework of the interdisciplinary MEDOC (MEDiterràneo OCcidental) European project, the crustal structures of the Tyrrhenian basin were explored carrying out the acquisition of five seismic lines. Each line was investigated using both Wide Angle Reflection/Refraction (WARR) and Multichannel Seismic reflection (MCS) techniques. In this prese...

In the framework of the interdisciplinary MEDOC (MEDiterràneo OCcidental) European project, the crustal structures of the Tyrrhenian basin were explored carrying out the acquisition of five seismic lines. Each line was investigated using both Wide Angle Reflection/Refraction (WARR) and Multichannel Seismic reflection (MCS) techniques. In this prese...

In the framework of the interdisciplinary MEDOC (MEDiterràneo OCcidental) European project, the crustal structures of the Tyrrhenian basin were explored carrying out the acquisition of five seismic lines. Each line was investigated using both Wide Angle Reflection/Refraction (WARR) and Multichannel Seismic reflection (MCS) techniques. In this prese...

Detailed swath bathymetry, high resolution seismic profiles and bottom sampling, collected during the SWIM 2005 and SWIM 2005 cruises, provide new data to constrain the emplacement mechanism of the Monchique-Madeira hotspot in the Central - Eastern Atlantic Sea. During last decades, although this volcanic province has been the object of several inv...

Extension of the continental lithosphere leads to the formation of rift basins and ultimately may create passive continental margins. The mechanisms that operate during the early stage of crustal extension are still intensely debated. We present the results from coincident multichannel seismic and wide‐angle seismic profiles that transect across th...

Recently acquired high-resolution multichannel seismic profiles together with bathymetric and sub-bottom profiler data from the external part of the Gulf of Cadiz (Iberia-Africa plate boundary) reveal active deformation involving old (Mesozoic) oceanic lithosphere. This area is located 180 km offshore the SW Iberian Peninsula and embraces the promi...

A Margem Sul Portuguesa Profunda (MSPP) define-se neste trabalho como um conjunto de domínios morfotectónicos limitados superiormente por um rebordo de erosão situado geralmente a profundidades superiores a cerca de 1000 m abaixo do nível do mar, que se desvanece progressivamente para leste, na direcção do estreito de Gibraltar. Os processos que mo...

The Gorringe Bank is a gigantic seamount that separates the Horseshoe and Tagus abyssal plains offshore SW Iberia, in a zone that hosts the convergent boundary between the Africa and Eurasia plates. Although the region has been the focus of numerous investigations since the early 1970s, the lack of appropriate geophysical data makes the nature of t...

The NEutrino Mediterranean Observatory-Submarine Network 1 (NEMO-SN1) seafloor observatory is located in the central Mediterranean Sea, Western Ionian Sea, off Eastern Sicily (Southern Italy) at 2100-m water depth, 25 km from the harbor of the city of Catania. It is a prototype of a cabled deep-sea multiparameter observatory and the first one opera...

Deepwater landslides are often underestimated as potential tsunami triggers. The North Gorringe avalanche (NGA) is a large (~80 km3 and 35 km runout) newly discovered and deepwater (2900 m to 5100 m depth) mass failure located at the northern fl ank of Gorringe Bank on the southwest Iberian margin. Steep slopes and pervasive fracturing are suggeste...

New seismic imaging and seismotectonic data from the southwest Iberian margin, the site of the present-day boundary between the European and African plates, reveal that active strike slip is occurring along two prominent lineaments that have recently been mapped using multibeam bathymetry. Multichannel seismic and subbottom profiler images acquired...

Located between Italy, Corsica, Sardinia and Sicily the Tyrrhenian Sea is a Neogene back-arc basin formed by continental extension related to the southeastward rollback of the subducting Ionian oceanic plate. This basin is an ideal place to study the evolution of extension process. The basin structure displays different amount of extension along it...

One of the main purposes of the NEAREST project (Integrated observation from NEAR shore sourcES of Tsunamis: towards an early warning system GOCE, contract n. 037110) was the identification and characterization of seismogenic and tsunamigenic structures in Gulf of Cadiz area, source region of the Lisbon 1755 earthquake and tsunami. To address this...

The Tyrrhenian basin has been created during the extension of continental lithosphere driven by the retreat of a Ionian slab across the mantle. The basin does not seem to be actively extending, but its preserved crustal structure provides information of the time evolution of the processes involved in rifting. The basin rifted from north to south, w...

The Tyrrhenian basin has developed during the Neogene in a convergence setting between the Nubian and the European plates. The aim of this work is to unravel at basin-scale, the geological processes that have been working during the last 15 M.y. and giving the current structures. Data used in this study consist in a serie of multichannel seismic pr...

The contourite drifts off southwest Iberia that formed as a result of the interaction of the Mediterranean Outflow Water (MOW) with the continental middle slope were studied in the Algarve margin using multichannel reflection seismic lines, oil-wells, piston cores, and a bathymetric compilation of four datasets. The seismostratigraphic interpretati...

The Mediterranean realm is characterized by Neogene tectonically-imbricated arcs and their corresponding basin systems. Although the structures have been the focus of numerous projects, and some arcs and basin deposits have been well studied, particularly in outcrops onshore, most basin-arc pairs lack modern, comprehensive geophysical studies. The...

The Tyrrhenian basin has been created by extension of continental lithosphere above a retreating slab during the Neogene. The basin is not currently extending, but its structure preserves information of the time evolution of the rifting process. The basin opened from north to south with different amounts of extension. The northern region stopped op...

Stretching and thinning of the continental lithosphere leads to rifting and the formation of passive continental margins. However, there is a discrepancy between horizontal extension by faulting and vertical crustal thinning. Research is ongoing to investigate this relationship. The Tyrrhenian Sea is a young rift basin of Neogene age located in the...

Located between Italy, Corsica, Sardinia and Sicily the Tyrrhenian Sea is a Neogen back-arc basin formed by continental extension attributed to the southeastward rollback of the subducting Ionian plate. This triangle-shaped basin is an ideal place to study the evolution of extension process. The basin displays different states of extension along it...

We present seismic images and the interpretation of the tectonic structure of the Tyrrhenian basin with data acquired during a cruise that took place in Spring 2010. The Tyrrhenian basin was formed by stretching of the upper plate during roll-back of the subducting Ionian plate below the European plate. To achieve the interpretation the seismic ima...

We investigate the crustal structure of the SW Iberian margin along a 340km-long refraction and wide-angle reflection seismic profile crossing from the central Gulf of Cadiz to the Variscan continental margin in the Algarve, Southern Portugal. The seismic velocity and crustal geometry model obtained by joint refraction and reflection travel-time in...

We investigate the crustal structure of the SW Iberian margin along a 340. km-long refraction and wide-angle reflection seismic profile crossing from the central Gulf of Cadiz to the Variscan continental margin in the Algarve, Southern Portugal. The seismic velocity and crustal geometry model obtained by joint refraction and reflection travel-time...

Here we report the major results of the EU Project NEAREST (Integrated observations from Near Shore Sources of Tsunami: toward an Early Warning System) carried out in the Gulf of Cadiz (SE Iberia) during Oct.1st 2006-March 31 2010. The Gulf of Cadiz it is one of the few geological environments able to generate transatlantic tsunamis, which can deep...

Terra Nova, 22, 494–500, 2010 New detailed swath bathymetry and bottom samples from Coral Patch and Ormonde seamounts provide constraints on the emplacement of the Madeira hotspot in the Eastern Atlantic Ocean. Swath bathymetric data document that Coral Patch is a composite structure, made up of at least nine distinct volcanic centres. Lithified pe...

The Tyrrhenian Sea has been regarded to as a back-arc basin connected to the roll-back of the Calabrian subduction zone. Subduction extends along the Apennines from peninsular Italy to Sicily. The Tyrrhenian started to form in the middle Miocene (12-10 Ma) and stretching more recently migrated to the south-east, in the southern Tyrrhenian basin, wh...

Caracterización de fallas activas y deslizamientos asociados en el Margen Sur de Iberia (Mar de Alboran y Golfo de Cadiz): Evidencias paleosísmicas E. Gràcia Abstract: During the last years we have carried out successive high-resolution marine geological and geophysical surveys to investigate the seismic potential of the slow-moving seismogenic fau...

A summary of the ship-board activities of a Reflection Seismic, magnetics and coring survey on the offshore SW Portugal is presented. The survey used R/V Urania of CNR for 35 days, inclusive of tran-sits from Livorno and to Napoli. Along with a description of technical details of the equipment employed, we discuss problems regarding data acquisitio...

During the last years we have carried out successive high-resolution marine geological and geophysical surveys to investigate the seismic potential of the slow-moving seismogenic faults from the South Iberian Margin. Based on multiscale acoustic mapping, sub-seafloor seismic imaging and dating methods we have characterized submarine fault systems w...

SUMÁRIO Efectuou-se a calibração estratigráfica das unidades sísmicas mais recentes identificadas na Bacia offshore do Algarve recorrendo à análise biostratigráfica (Nanofósseis calcários e Foraminíferos) do core de pistão SWIM04-39. Obteve-se uma idade de cerca de 4.0 Ma (Pliocénico Inferior, Zancliano) para as associações fitoplanctónica e faunís...

The Gulf of Cadiz is one of the seismogenic-tsunamigenic areas around Europe; it is one of the few geological environments able to generate transatlantic tsunamis, which can deeply affect the coasts of Iberia and Morocco, but with significant effects in northern Europe and the Caribbean Islands. Here we report the major results of the EU Project NE...

The joint use of more than 10.000 km multichannel seismic reflection profiles and 180.000km2 of multibeam swath bathymetry and backscatter allowed for a new vision of the seafloor tectonic and geomorphic processes of the area that encompasses the present day plate boundary between Africa and Eurasia, between the Gibraltar Straits and the Tore-Madei...

Teleseismic data recorded by the NEAREST (Integrated observation from NEAR shore sourcES of Tsunamis: towards an early warning system) temporary array are inverted for the 3-D upper mantle P-wave velocity structure beneath the SW margin of Iberia including the Gulf of Cadiz. In this area, the convergence between the European and African plates play...

The Gulf of Cadiz is one of two the test sites chosen for the demonstration of the ESONET - LIDO Demonstration Mission (DM) [1], which will establish a first nucleus of regional network of multidisciplinary sea floor observatories. The Gulf of Cadiz is a highly populated area, characterized by tsunamigenic sources, which caused the devastating eart...

An eleven-month deployment of 25 ocean bottom seismometers provides an unprecedented opportunity to study low-magnitude local earthquakes in the complex transpressive plate boundary setting of the Gulf of Cadiz, known for the 1755 Lisbon earthquake and tsunami. 36 relocated earthquakes (ML 2.2 to 4.8) concentrate at 40–60 km depth, near the base of...

The Gulf of Cadiz, off SW Iberia and the NW Moroccan margin, straddles the cryptic plate boundary between Africa and Eurasia, a region where the orogenic Alpine compressive deformation in the continental collision zone passes laterally to the west to strike-slip deformation. A set of new multibeam bathymetry, multi-channel and single-channel seismi...

The missing link in the plate boundary between Eurasia and Africa in the central Atlantic is presented and discussed. A set of almost linear and sub parallel dextral strike–slip faults, the SWIM1 Faults, that form a narrow band of deformation over a length of 600 km coincident with a small circle centred on the pole of rotation of Africa with respe...

The missing link in the plate boundary between Eurasia and Africa in the central Atlantic is presented and discussed. A set of almost linear and sub parallel dextral strike–slip faults, the SWIM1 Faults, that form a narrow band of deformation over a length of 600 km coincident with a small circle centred on the pole of rotation of Africa with respe...

The Tyrrhenian basin of the Mediterranean started its formation in the Early Miocene, and some processes may be still active in the eastern area. It is generally accepted that the evolution of this basin is related to the eastward migration of the subduction zone between the African plate and the European plate. The subducting plate has been rollin...

The geophysical and geological investigations conducted so far in the Gulf of Cadiz allow us today to have an idea of the largest active faults that can generate destructive earthquakes and tsunamis comparable to the Nov 1st, 1755 Lisbon event. However, their kinematics and seismic activity are poorly known because the seismic networks based on lan...

NEAREST (Integrated observation from NEAR shore sourcES of Tsunamis: towards an early warning system) is an EC funded project (GOCE, contract n. 037110), which aims at the identification and characterization of potential near-shore sources of tsunamis in the Gulf of Cadiz. This area is well known from the catastrophic earthquake and tsunami occurre...

The Gulf of Cadiz (GC) hosts the present-day NW-SE plate convergence between Eurasia and Africa Plates west of the Straits of Gibraltar at a rate about 4 mm/yr. The convergence is accommodated over a wide and diffuse deformation zone with moderate magnitude seismic activity. Nevertheless, some of the largest events in Western Europe occurred in the...

Recent mapping of the Gulf of Cadiz seafloor permitted to identify major tectonic lineaments: the SWIM lineaments (Zitellini et al., 2009) and Cadiz lineament, striking WNW-ESE and NE-SW, respectively. Multibeam swath bathymetry and interpretation of multi-channel seismic data indicate that these features can be interpreted to correspond to the sea...

Prototipo di Tsunami Warning nel quadro del progetto EC NEAREST Nell' ambito del progetto NEAREST finanziato dalla EC sono stati sviluppati alcuni elementi di un sistema di allerta per tsunami, fra i quali un prototipo di detector di onde anomale istallato a bordo dell' osservatorio abissale GEOSTAR: l' osservatorio con il detector di onde anomale...

On August 25 at 10:15 p.m. G.M.T. the first prototype of an underwater tsunami observatory was successfully deployed at 3207 m water depth in the Gulf of Cadiz. The deployment,150 km South of Portugal, was planned within the NEAREST project (Integrated observations from NEAR shore sources of Tsunamis: towards an early warning system - EC, cont. 371...

On August 25th 2007 a tsunami detector installed onboard the multi-parameter observatory GEOSTAR was successfully deployed at 3200 b. s. l. in the Gulf of Cadiz, Portugal. This activity is within the NEAREST EC Project (http://nearest.bo.ismar.cnr.it/ ). Among other deliverables, the NEAREST project will produce and test the basic parts of an opera...

(S) - IASPEI - International Association of Seismology and Physics of the Earth's Interior JSS016 Oral Presentation 2348 Multiparameter seafloor observatory deployed for tsunami warning Author : Dr. Francesco Chierici Istituto di Radioastronomia Istituto Nazionale di Astrofisica Co-Author: Luca Pignagnoli, Laura Beranzoli, Francesco Gasparoni, Luis...

SUMMARY Biostratigraphic calibration of the seismic units recognized in the offshore Algarve Basin was made, based on the identification of Calcareous nanofossil and Foraminifera assemblages present in the core SWIM04-39. An age of about 4.0 Ma (Early Pliocene, Zanclean) was determinate for these assemblages. Using this data is possible to place th...

The SW Iberia Margin, located at the convergence of the European and African Plates, is the source of the largest earthquakes and tsunamis in Western Europe, such as the catastrophic 1755 Great Lisbon earthquake. High-resolution swath bathymetry data allows us to recognize the detailed morphology of the Gulf of Cadiz and to identify recent seafloor...

ESONET proposes a network of sea floor observatories around the European Ocean Margin from the Arctic Ocean to the Black Sea for strategic long term monitoring as part of a GMES with capability in geophysics, geotechnics, chemistry, biochemistry, oceanography, biology and fisheries. Long-term data collection and alarm capability in the event of haz...

The tsunami generated by the 1755.11.01 earthquake, as reported by coeval sources, was the major event of its kind in the North Atlantic, until nowadays. The coasts of the Iberian Peninsula and Northwest Morocco were deeply affected by that phenomenon, with tremendous impacts on the city of Lisbon. For the last 20 years, significant support was rec...

ESONET is a proposed sub sea component of the European GMES (Global Monitoring for Environment and Security) to provide strategic long term monitoring capability in geophysics, geotechnics, chemistry, biochemistry, oceanography, biology and fisheries. To provide representative sampling around Europe 10 nodes are proposed in contrasting oceanographi...

Over the last two decades numerous studies have investigated the structure of the west Iberia continental margin, a non-volcanic margin characterized by a broad continent-ocean transition (COT). However, the nature and structure of the crust of the segment of the margin off SW Iberia is still poorly understood, because of sparse geophysical and geo...