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Registros recuperados: 17 | |
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Dellong, David; Klingelhoefer, Frauke; Dannowski, Anke; Kopp, Heidrun; Murphy, Shane; Graindorge, David; Margheriti, Lucia; Moretti, Milena; Barreca, Giovanni; Scarfì, Luciano; Polonia, Alina; Gutscher, Marc-andre. |
The Calabrian subduction zone is one of the narrowest arcs on Earth and a key area to understand the geodynamic evolution of the Mediterranean and other marginal seas. Here in the Ionian Sea, the African plate subducts beneath Eurasia. Imaging the boundary between the downgoing slab and the upper plate along the Calabrian subduction zone is important for assessing the potential of the subduction zone to generate mega‐thrust earthquakes and was the main objective of this study. Here we present and analyze the results from a 380 km long, wide‐angle seismic profile spanning the complete subduction zone, from the deep Ionian Basin and the accretionary wedge to NE Sicily, with additional constraints offered by 3‐D Gravity modeling and the analysis of earthquake... |
Tipo: Text |
Palavras-chave: Ionian Basin; Wide-angle seismic; Gravity; Crustal structure; Seismicity; Tomography. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00592/70442/68544.pdf |
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Micallef, Aaron; Camerlenghi, Angelo; Georgiopoulou, Aggeliki; Garcia-castellanos, Daniel; Gutscher, Marc-andre; Lo Iacono, Claudio; Huvenne, Veerle A. I.; Mountjoy, Joshu J.; Paull, Charles K.; Le Bas, Timothy; Spatola, Daniele; Facchin, Lorenzo; Accettella, Daniela. |
Carbonate escarpments are submarine limestone and dolomite cliffs that have been documented in numerous sites around the world. Their geomorphic evolution is poorly understood due to difficulties in assessing escarpment outcrops and the limited resolution achieved by geophysical techniques across their steep topographies. The geomorphic evolution of carbonate escarpments in the Mediterranean Sea has been influenced by the Messinian salinity crisis (MSC). During the MSC (5.97-533 Ma), the Mediterranean Sea became a saline basin due to a temporary restriction of the Atlantic-Mediterranean seaway, resulting in the deposition of more than one million cubic kilometres of salt. The extent and relative chronology of the evaporative drawdown phases associated to... |
Tipo: Text |
Palavras-chave: Malta Escarpment; Geomorphic evolution; Submarine canyon; Palaeoshoreline; Sea level drawdown; Messinian salinity crisis. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00485/59686/83482.pdf |
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Micallef, Aaron; Camerlenghi, Angelo; Garcia-castellanos, Daniel; Otero, Daniel Cunarro; Gutscher, Marc-andre; Barreca, Giovanni; Spatola, Daniele; Facchin, Lorenzo; Geletti, Riccardo; Krastel, Sebastian; Gross, Felix; Urlaub, Morelia. |
The Messinian salinity crisis (MSC) - the most abrupt, global-scale environmental change since the end of the Cretaceous - is widely associated with partial desiccation of the Mediterranean Sea. A major open question is the way normal marine conditions were abruptly restored at the end of the MSC. Here we use geological and geophysical data to identify an extensive, buried and chaotic sedimentary body deposited in the western Ionian Basin after the massive Messinian salts and before the Plio-Quaternary open-marine sedimentary sequence. We show that this body is consistent with the passage of a megaflood from the western to the eastern Mediterranean Sea via a south-eastern Sicilian gateway. Our findings provide evidence for a large amplitude drawdown in the... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00485/59687/62765.pdf |
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Klingelhoefer, Frauke; Biari, Youssef; Sahabi, Mohamed; Aslanian, Daniel; Schnabel, Michael; Matias, Luis; Benabdellouahed, Massinissa; Funck, Thomas; Gutscher, Marc-andre; Reichert, Christian; Austin, James A.. |
Deep seismic data represent a key to understand the geometry and mechanism of continental rifting. The passive continental margin of NW-Africa is one of the oldest on earth, formed during the Upper Triassic–Lower Liassic rifting of the central Atlantic Ocean over 200 Ma. We present new and existing wide-angle and reflection seismic data from four study regions along the margin located in the south offshore DAKHLA, on the central continental margin offshore Safi, in the northern Moroccan salt basin, and in the Gulf of Cadiz. The thickness of unthinned continental crust decreases from 36 km in the North to about 27 km in the South. Crustal thinning takes place over a region of 150 km in the north and only 70 km in the south. The North Moroccan Basin is... |
Tipo: Text |
Palavras-chave: Moroccan continental margin; Wide-angle seismic; Passive margins; Deep structure; Plate reconstruction. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00316/42685/42058.pdf |
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Dannowski, Anke; Kopp, Heidrun; Klingelhoefer, Frauke; Klaeschen, Dirk; Gutscher, Marc-andre; Krabbenhoeft, Anne; Dellong, David; Rovere, Mickael; Graindorge, David; Papenberg, Cord; Klaucke, Ingo. |
The nature of the Ionian Sea crust has been the subject of scientific debate for more than 30 years, mainly because seismic imaging of the deep crust and upper mantle of the Ionian Abyssal Plain (IAP) has not been conclusive to date. The IAP is sandwiched between the Calabrian and Hellenic subduction zones in the central Mediterranean. To univocally confirm the proposed oceanic nature of the IAP crust as a remnant of the Tethys ocean and to confute its interpretation as a strongly thinned part of the African continental crust, a NE-SW oriented 131 km long seismic refraction and wide-angle reflection profile consisting of eight ocean bottom seismometers and hydrophones was acquired in 2014. A P-wave velocity model developed from travel time forward... |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00473/58431/61006.pdf |
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Gutscher, Marc-andre; Kopp, Heidrun; Krastel, Sebastian; Bohrmann, Gerhard; Garlan, Thierry; Zaragosi, Sebastien; Klaucke, Ingo; Wintersteller, Paul; Loubrieu, Benoit; Le Faou, Yann; San Pedro, Laurine; Dominguez, Stephane; Rovere, Marzia; De Lepinay, Bernard Mercier; Ranero, Cesar; Sallares, Valenti. |
The detailed morphology and internal structure of the Calabrian accretionary wedge and adjacent Eastern Sicily margin are imaged in unprecedented detail by a combined dataset of multi-beam bathymetry and high-resolution seismic profiles. The bathymetric data represent the results of 6 recent marine geophysical surveys since 2010 as well as a compilation of earlier surveys presented as a 2 arc-sec (60 m) grid. Several distinct morpho-tectonic provinces are identified including: the deeply incised Malta–Hyblean Escarpment, numerous submarine canyons, broad regions of relatively flat seafloor dominated by fields of sediment waves, the gently undulating anticlinal fold-and-thrust belts of the external Calabrian accretionary wedge and the adjacent portion of... |
Tipo: Text |
Palavras-chave: Subduction; Active faults; Eurasia-Africa plate boundary; Bathymetry; Seismic profiles; Accretionary wedge. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00366/47685/47853.pdf |
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Gallais, Flora; Graindorge, David; Gutscher, Marc-andre; Klaeschen, Dirk. |
The rollback of a segmented slab of oceanic lithosphere is typically accompanied by vertical lithospheric tear fault(s) along the lateral slab edge(s) and by strike slip movement in the upper plate, defined as a STEP fault (Subduction Tear Edge Propagator). The Neogene evolution of the Central Mediterranean is dominated by the interaction between the slow Africa–Eurasia convergence and the SE-ward rollback of the Ionian slab, that leads to the back-arc opening of the Tyrrhenian Sea. Here, we present post-stack time migrated and pre-stack depth migrated Archimede (1997) multichannel seismic lines, that were acquired offshore eastern Sicily, at the foot of the Malta escarpment. First, we identify the recent deformation along the lateral ramp of the Calabrian... |
Tipo: Text |
Palavras-chave: Tear fault; Rollback; Accretion; Multi-channel seismic reflection. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00118/22878/21386.pdf |
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Quentel, Elise; Carton, Xavier; Gutscher, Marc-andre. |
Hydrological and marine seismic data, collected in the Gulf of Cadiz (respectively in July 1999, 2000, 2001 and 2002, and in April 2000 and 2001) are analysed to reveal the various structures of Mediterranean Water (MW). Both the hydrological and seismic data clearly identify the MW undercurrents on the Iberian slope, detached MW eddies (meddies and a cyclone) and smaller fragments of MW (filaments and small eddies). Seismic reflectivity and synthetic reflectivity computed from hydrology, indicate that strong acoustic reflectors, associated with 8 - 64 m thick homogeneous water layers, are found above and below meddies and filaments, around the MW undercurrents, but mostly in the lower part of cyclones and below submesoscale eddies. Reflectors are also... |
Tipo: Text |
Palavras-chave: Mediterranean Water; Eddies; Undercurrent; Layering; Hydrological Data; Seismic Reflectivity; Submesoscale Structures. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00129/24006/21962.pdf |
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Gutscher, Marc-andre; Olivet, Jean-louis; Aslanian, Daniel; Eissen, Jp; Maury, Rene. |
Since flat subduction of the Nazca Plate beneath Peru was first recognized in the 1970s and 1980s a satisfactory explanation has eluded researchers. We present evidence that a lost oceanic plateau (Inca Plateau) has subducted beneath northern Peru and propose that the combined buoyancy of Inca Plateau and Nazca Ridge in southern Peru supports a 1500 km long segment of the downgoing slab and shuts off arc volcanism. This conclusion is based on an analysis of the seismicity of the subducting Nazca Plate, the structure and geochemistry of the Marquesas Plateau as well as tectonic reconstructions of the Pacific¿Farallon spreading center 34 to 43 Ma. These restore three sub¿parallel Pacific oceanic plateaus; the Austral, Tuamotu and Marquesas, to two Farallon... |
Tipo: Text |
Palavras-chave: Nazca Plate; Subduction; Nazca Ridge; Peru; Reconstruction. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/publication-360.pdf |
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Dellong, David; Klingelhoefer, Frauke; Dannowski, Anke; Kopp, Heidrun; Murphy, Shane; Graindorge, David; Margheriti, Lucia; Moretti, Milena; Barreca, Giovanni; Scarfì, Luciano; Polonia, Alina; Gutscher, Marc-andre. |
Andrea Argnani in his comment on Dellong et al., 2020 (Geometry of the deep Calabrian subduction (Central Mediterranean Sea) from wide‐angle seismic data and 3D gravity modeling), proposes an alternate interpretation of the wide‐angle seismic velocity models presented by Dellong et al., 2018 and Dellong et al., 2020 and proposes a correction of the literature citations in these paper. In this reply, we discuss in detail all points raised by Andrea Argnani. |
Tipo: Text |
Palavras-chave: Wide-angle seismic; Ionian basin; Gravity. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00640/75196/75326.pdf |
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Hensen, Christian; Duarte, Joao C.; Vannucchi, Paola; Mazzini, Adriano; Lever, Mark A.; Terrinha, Pedro; Géli, Louis; Henry, Pierre; Villinger, Heinrich; Morgan, Jason; Schmidt, Mark; Gutscher, Marc-andre; Bartolome, Rafael; Tomonaga, Yama; Polonia, Alina; Gràcia, Eulàlia; Tinivella, Umberta; Lupi, Matteo; Çağatay, M. Namık; Elvert, Marcus; Sakellariou, Dimitris; Matias, Luis; Kipfer, Rolf; Karageorgis, Aristomenis P.; Ruffine, Livio; Liebetrau, Volker; Pierre, Catherine; Schmidt, Christopher; Batista, Luis; Gasperini, Luca; Burwicz, Ewa; Neres, Marta; Nuzzo, Marianne. |
Marine transform faults and associated fracture zones (MTFFZs) cover vast stretches of the ocean floor, where they play a key role in plate tectonics, accommodating the lateral movement of tectonic plates and allowing connections between ridges and trenches. Together with the continental counterparts of MTFFZs, these structures also pose a risk to human societies as they can generate high magnitude earthquakes and trigger tsunamis. Historical examples are the Sumatra-Wharton Basin Earthquake in 2012 (M8.6) and the Atlantic Gloria Fault Earthquake in 1941 (M8.4). Earthquakes at MTFFZs furthermore open and sustain pathways for fluid flow triggering reactions with the host rocks that may permanently change the rheological properties of the oceanic... |
Tipo: Text |
Palavras-chave: Transform faults; Fractures zones; Coupling of seismicity and fluid flow; Microbial life; Heat flow; Fluid geochemistry; Seafloor observation systems; Seismic precursors. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00489/60085/63422.pdf |
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Gutscher, Marc-andre; Royer, Jean-yves; Graindorge, David; Murphy, Shane; Klingelhoefer, Frauke; Aiken, Chastity; Cattaneo, Antonio; Barreca, Giovanni; Quetel, Lionel; Riccobene, Giorgio; Petersen, Florian; Urlaub, Morelia; Krastel, Sebastian; Gross, Felix; Kopp, Heidrun; Margheriti, Lucia; Beranzoli, Laura. |
Laser reflectometry (BOTDR), commonly used for structural health monitoring (bridges, dams, etc.), will for the first time be applied to study movements of an active fault on the seafloor 25 km offshore Catania Sicily. The goal of the European funded FOCUS project (ERC Advanced Grant) is to connect a 6-km long strain cable to the EMSO seafloor observatory in 2100 m water depth. Laser observations will be calibrated by seafloor geodetic instruments and seismological stations. A long-term goal is the development of dual-use telecom cables with industry partners. |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00493/60430/63872.pdf |
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Gallais, Flora; Graindorge, David; Gutscher, Marc-andre. |
In his Comment, A. Argnani argues that our interpretation of the STEP fault (named STEP-1 fault, in the Comment) is poorly constrained by the seismic data used in Gallais et al. (2013), and he particularly disagrees with our identification north of the Alfeo Seamount. A. Argnani is convinced that the tear fault is expressed by a belt of surface deformation, close to the Malta Escarpment. However, none of the seismic images published by A. Argnani show a crustal scale structure that could be associated with the presence at depth of a lithospheric tear. In that paper we documented the presence of a sub-vertical crustal scale fault, located 50 km east of the Malta Escarpment, with a northward increasing vertical offset (Gallais et al., 2013). The track of... |
Tipo: Text |
Palavras-chave: Subduction zones; Lithospheric fault; Slab roll-back; Active deformation; Multichannel seismic profiles; Slab tear. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00160/27133/25331.pdf |
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Gutscher, Marc-andre; Dominguez, Stephane; Mercier De Lepinay, Bernard; Pinheiro, Luis; Gallais, Flora; Babonneau, Nathalie; Cattaneo, Antonio; Le Faou, Yann; Barreca, Giovanni; Micallef, Aaron; Rovere, Marzia. |
Subduction of a narrow slab of oceanic lithosphere beneath a tightly curved orogenic arc requires the presence of at least one lithospheric scale tear fault. While the Calabrian subduction beneath southern Italy is considered to be the type example of this geodynamic setting, the geometry, kinematics and surface expression of the associated lateral, slab tear fault offshore eastern Sicily remain controversial. Results from a new marine geophysical survey conducted in the Ionian Sea, using high-resolution bathymetry and seismic profiling reveal active faulting at the seafloor within a 140 km long, two-branched fault system near Alfeo Seamount. The previously unidentified 60 km long NW trending North Alfeo Fault system shows primarily strike-slip kinematics... |
Tipo: Text |
Palavras-chave: Slab tear; Subduction; Mediterranean; Bathymetry; Seismics; Active faults. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00318/42924/42421.pdf |
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Registros recuperados: 17 | |
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