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| Registros recuperados: 32 | |
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| Henry, P.; Grall, Celine; Kende, J.; Viseur, S.; Ozeren, M. S.; Sengor, A. M. C.; Dupre, Stephanie; Scalabrin, Carla; Geli, Louis. |
| The Sea of Marmara is traversed by the North Anatolian Fault system and also presents abundant emission sites of methane gas into the water column. In order to assess the spatial relationship between gas emissions and active faults, the distribution of distances between gas emission sites and the nearest fault is calculated and compared with the distribution of distances between a uniform random distribution of points (Poisson process representing the null hypothesis of an absence of relationship between gas emissions and faults) and the nearest fault. Interestingly, the distance distribution for the Poisson process is nearly exponential, indicating that the fault map does not have a characteristic scale other than that representing the intensity of the... |
| Tipo: Text |
Palavras-chave: Cold seeps; Gas emissions; Transform plate boundary; Strike-slip fault; Damage zone. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00441/55252/56739.pdf |
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| Fontanier, Christophe; Mamo, Briony; Toucanne, Samuel; Bayon, Germain; Schmidt, Sabine; Deflandre, Bruno; Dennielou, Bernard; Jouet, Gwenael; Garnier, Eline; Sakai, Saburo; Lamas, Ruth Martinez; Duros, Pauline; Toyofuku, Takashi; Sale, Aurelien; Belleney, Deborah; Bichon, Sabrina; Boissier, Audrey; Cheron, Sandrine; Pitel, Mathilde; Roubi, Angelique; Rovere, Mickael; Gremare, Antoine; Dupre, Stephanie; Jorry, Stephan. |
| In this short communication, we present a multidisciplinaty study of sedimentary records collected from a deep-sea interfluve proximal to the mouths of major northwestern Madagascan rivers. For the last 60 years, the seafloor has been repeatedly disturbed by the deposition of organic rich, tropical, terrestrial sediments causing marked reductions in benthic biodiversity. Increased soil erosion due to local land-use, deforestation and intensifying tropical cyclones are potential causes for this sedimentary budget and biodiversity shift. Our marine sedimentary records indicate that until now, these conditions have not occurred within the region for at least 20,000 years. |
| Tipo: Text |
Palavras-chave: Multidisciplinary study; Benthic foraminifera; Land-use; Tropical cyclones. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00413/52488/53276.pdf |
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| Pierre, Catherine; Bayon, Germain; Blanc-valleron, Marie-madeleine; Mascle, Jean; Dupre, Stephanie. |
| On the passive margin of the Nile deep-sea fan, the active Cheops mud volcano (MV; ca. 1,500 m diameter, ~20–30 m above seafloor, 3,010–3,020 m water depth) comprises a crater lake with hot (up to ca. 42 °C) methane-rich muddy brines in places overflowing down the MV flanks. During the Medeco2 cruise in fall 2007, ROV dives enabled detailed sampling of the brine fluid, bottom lake sediments at ca. 450 m lake depth, sub-surface sediments from the MV flanks, and carbonate crusts at the MV foot. Based on mineralogical, elemental and stable isotope analyses, this study aims at exploring the origin of the brine fluid and the key biogeochemical processes controlling the formation of these deep-sea authigenic carbonates. In addition to their patchy occurrence in... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00186/29735/28189.pdf |
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| Fabri, Marie-claire; Loubrieu, Benoit; Dupre, Stephanie; Opderbecke, Jan; Lurton, Xavier. |
| Ce document a pour objectif de préparer une réunion sur le choix du type de charge utile "Acoustique" pour le H-ROV. Ce document s'intéresse à la charge utile "cartographie acoustique". Il est réalisé avec l'objectif de préparer une réunion du groupe de travail scientifique du H-ROV. Il propose un bilan des différentes charges utiles acoustiques embarquables sur un engin sous-marin, ainsi que leur avantages et leurs inconvénients au regard des caractéristiques techniques du H-ROV. Au final un SONDEUR MULTIFAISCEAUX a été le choix considéré comme étant le plus adapté à l'environnement probable d'exploration du HROV (milieu à fort relief) ainsi qu'à ses caractéristiques techniques (autonomie réduite). Lors de l'intégration sur le SKID "Acoustique", il faudra... |
| Tipo: Text |
Palavras-chave: H-ROV; Cartographie acoustique. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00233/34382/32753.pdf |
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| Mascle, Jean; Mary, Flore; Praeg, Daniel; Brosolo, Laetitia; Camera, Laurent; Ceramicola, Silvia; Dupre, Stephanie. |
| Existing knowledge on the distribution of mud volcanoes (MVs) and other significant fluid/free gas-venting features (mud cones, mud pies, mud-brine pools, mud carbonate cones, gas chimneys and, in some cases, pockmark fields) discovered on the seafloor of the Mediterranean Sea and in the nearby Gulf of Cadiz has been compiled using regional geophysical information (including multibeam coverage of most deepwater areas). The resulting dataset comprises both features proven from geological sampling, or in situ observations, and many previously unrecognized MVs inferred from geophysical evidence. The synthesis reveals that MVs clearly have non-random distributions that correspond to two main geodynamic settings: (1) the vast majority occur along the various... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00185/29644/28073.pdf |
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| Dupre, Stephanie; Berger, Laurent; Le Bouffant, Naig; Scalabrin, Carla; Bourillet, Jean-francois. |
| Fishery acoustic surveys conducted in the Bay of Biscay and dedicated to monitoring and predicting pelagic ecosystem evolution reveal numerous active seeps on the Aquitaine Shelf, east of the shelf break, at water depths ranging from 140 to 185 m. Some acoustic anomalies recorded in the water column with hull-mounted single and multibeam echosounders are clearly caused by fluid escape at the seabed, most likely gases. These fluid emissions are associated at the seafloor with high backscatter subcircular small-scale mounds, on average less than 2 m high and a few metres in diameter. Based on near-bottom video and acoustic surveys, these mounds are interpreted to be by-products of gas seepage, possibly methane-derived authigenic carbonates. The spatial... |
| Tipo: Text |
Palavras-chave: Bay of Biscay; Aquitaine Shelf; Parentis Basin; Fluid; Seepage; Acoustics. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00201/31192/29888.pdf |
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| Praeg, Daniel; Ketzer, Joao Marcelo; Augustin, Adolfo Herbert; Migeon, Sebastien; Ceramicola, Silvia; Dano, Alexandre; Ducassou, Emmanuelle; Dupre, Stephanie; Mascle, Jean; Rodrigues, Luiz Frederico. |
| On the central Nile deep-sea fan, stratified sediments overlying mass-transport deposits (MTDs) are deformed into slope-parallel seabed undulations associated with fluid seepage. The western part of this system, in water depths of 1,950–2,250 m, is examined using multi-frequency data from hull-mounted and deep-towed swath/profiling systems. Sub-bottom profiles show sub-vertical fluid pipes that terminate both at and below seabed, and gas signatures along fault planes bounding the undulations. Fluid seepage is recorded by high- to intermediate-backscatter patches (HBPs, IBPs) that differ in appearance on multibeam imagery (30 kHz, ≤3 m penetration) and sidescan swaths (170/190 kHz, <0.1 m penetration). Comparison of the two suggests a distinction of (a)... |
| Tipo: Text |
Palavras-chave: Slope undulations; Fluid seeps; Backscatter; Carbonates; Pipes; Faults. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00158/26956/25251.pdf |
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| Bayon, Germain; Dupre, Stephanie; Ponzevera, Emmanuel; Etoubleau, Joel; Cheron, Sandrine; Pierre, Catherine; Mascle, Jean; Boetius, Antje; De Lange, Gert J.. |
| Marine sediments at ocean margins vent substantial amounts of methane(1,2). Microbial oxidation of the methane released can trigger the precipitation of carbonate within sediments and support a broad diversity of seafloor ecosystems(3,4). The factors controlling microbial activity and carbonate precipitation associated with the seepage of submarine fluid over geological time remain poorly constrained. Here, we characterize the petrology and geochemistry of rocks sampled from metre-size build-ups of methane-derived carbonate chimneys located at the Amon mud volcano on the Nile deep-sea fan. We find that these carbonates comprise porous structures composed of aggregated spherules of aragonite, and closely resemble microbial carbonate reefs forming at present... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26734/24854.pdf |
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| Geli, Louis; Henry, P.; Grall, Celine; Tary, Jean-baptiste; Lomax, A.; Batsi, Evangelia; Riboulot, Vincent; Cros, Estelle; Gurbuz, C.; Isik, S. E.; Sengor, A. M. C.; Le Pichon, X.; Ruffine, Livio; Dupre, Stephanie; Thomas, Yannick; Kalafat, D.; Bayrakci, G.; Coutellier, Q.; Regnier, Thibaut; Westbrook, Graham; Saritas, H.; Cifci, G.; Cagatay, M. N.; Ozeren, M. S.; Gorur, N.; Tryon, M.; Bohnhoff, M.; Gasperini, L.; Klingelhoefer, Frauke; Scalabrin, Carla; Augustin, Jean-marie; Embriaco, D.; Marinaro, G.; Frugoni, F.; Monna, S.; Etiope, G.; Favali, P.; Becel, A.. |
| Understanding micro-seismicity is a critical question for earthquake hazard assessment. Since the devastating earthquakes of Izmit and Duzce in 1999, the seismicity along the submerged section of North Anatolian Fault within the Sea of Marmara (comprising the “Istanbul seismic gap”) has been extensively studied in order to infer its mechanical behaviour (creeping vs locked). So far, the seismicity has been interpreted only in terms of being tectonic-driven, although the Main Marmara Fault (MMF) is known to strike across multiple hydrocarbon gas sources. Here, we show that a large number of the aftershocks that followed the M 5.1 earthquake of July, 25th 2011 in the western Sea of Marmara, occurred within a zone of gas overpressuring in the 1.5–5 km depth... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00439/55072/56500.pdf |
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| Geli, Louis; Henry, P; Zitter, T; Dupre, Stephanie; Tryon, M; Cagatay, M; De Lepinay, B; Le Pichon, X; Sengor, A; Gorur, N; Natalin, B; Ucarkus, G; Oezeren, S; Volker, D; Gasperini, L; Burnard, P; Bourlange, S. |
| The submerged section of the North Anatolian fault within the Marmara Sea was investigated using acoustic techniques and submersible dives. Most gas emissions in the water column were found near the surface expression of known active faults. Gas emissions are unevenly distributed. The linear fault segment crossing the Central High and forming a seismic gap - as it has not ruptured since 1766, based on historical seismicity [Ambraseys, N.N., and Jackson, J.A., (2000), Seismicity of the Sea of Marmara (Turkey) since 1500, Geophys. J. Int., 141, (3), F1-F6. (doi:10.1046/j.1365-246x.2000.00137.x: Ambraseys, N., (2002), The seismic activity of the Marmara Region over the last 2000 years, Bull. Seism. Soc. Am., 92, 1-18; Parson, T., (2004), Recalculated... |
| Tipo: Text |
Palavras-chave: North Anatolian Fault; Marmara Sea; Gas emission; Fluids; Seismicity. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4681.pdf |
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| Ruffine, Livio; Donval, Jean-pierre; Croguennec, Claire; Bignon, Laurent; Birot, Dominique; Battani, Anne; Bayon, Germain; Caprais, Jean-claude; Lanteri, Nadine; Levache, Denis; Dupre, Stephanie. |
| During the scientific expedition GAZCOGNE2 at the Bay of Biscay nine gas seeps were sampled for the first time and their flux was measured using an in situ pressure-preservation sampler (PEGAZ, ©IFREMER). Overall, three sites were investigated to determine the nature and the origin of the gases bubbling at the seafloor and forming acoustic plumes into the water column, as this was the question raised fromthe first geologic study of the area.This has guided our study and accordingly corresponds to themain purpose of the present article.Thus, themolecular and isotopic (𝛿D and 𝛿13C) analyses revealed that the gas seeps were primarily composed of methane. Both methane and ethane are of microbial origin, and the former has been generated by... |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00394/50579/51270.pdf |
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| Ondreas, Helene; Olu, Karine; Dupre, Stephanie; Scalabrin, Carla; Alix, Anne-sophie; Garrocq, Clément; Ruffine, Livio. |
| The Sea of Marmara hosts part of the North Anatolian Fault as an active submarine strike-slip fault. This area has suffered numerous earthquakes and presents a major seismic risk. Although the Sea of Marmara has been studied for many years, the link between geological morphostructures, the nature of fluids and biological communities is still rarely described. During the Marsite cruise (November 2014), dives with Remotely Operated Vehicle (ROV) VICTOR 6000 focused on detailed seafloor explorations of four different areas: the Central and Western highs and the Tekirdağ and Çinarcik basins. Based on 130 h of in situ videos, high-resolution seafloor mapping of seeps was conducted, emphasizing their significant geological and biological diversity from one... |
| Tipo: Text |
Palavras-chave: Sea of Marmara; Cold seeps; Fluids; Seismogenic faults; Chemosynthetic fauna; Methane. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00624/73623/73040.pdf |
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| Dupre, Stephanie; Buffet, G.; Mascle, J.; Foucher, Jean-paul; Gauger, S.; Boetius, A.; Marfia, Christian. |
| Two highly active mud volcanoes located in 990-1,265 m water depths were mapped on the northern Egyptian continental slope during the BIONIL expedition of R/V Meteor in October 2006. High-resolution swath bathymetry and backscatter imagery were acquired with an autonomous underwater vehicle (AUV)-mounted multibeam echosounder, operating at a frequency of 200 kHz. Data allowed for the construction of similar to 1 m pixel bathymetry and backscatter maps. The newly produced maps provide details of the seabed morphology and texture, and insights into the formation of the two mud volcanoes. They also contain key indicators on the distribution of seepage and its tectonic control. The acquisition of high-resolution seafloor bathymetry and acoustic imagery maps... |
| Tipo: Text |
Palavras-chave: Eastern Mediterranean; Seafloor morphology; Backscatter; Bathymetry; AUV; Nile Deep Sea Fan; Mud volcanoes. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6395.pdf |
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| Pierre, Catherine; Mascle, Jean; Dupre, Stephanie. |
| The MEDECO Leg 2 cruise followed the MEDECO Leg 1 cruise that had crossed the Mediterranean Sea from the west to the east to study benthic communities of the Var canyon, deep corals found on the Calabrian Margin and cold seep ecosystems of the Mediterranean Ridge. The main objective of the MEDECO Leg 2 cruise was to study and compare, using a multidisciplinary approach, the structure and dynamics of deep-sea ecosystems at various active cold seep sites from the Nile deep sea fan and the Calabrian Arc, in the Eastern Mediterranean sea. During MEDECO Legs 1 & 2, a multiscale strategy was promoted to integrate (1) a high resolution cartography of geological structures (km2 scale), (2) a detailed mapping, including video imagery, of smaller-scale areas... |
| Tipo: Text |
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| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00134/24550/22583.pdf |
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| Huguen, Caroline; Foucher, Jean-paul; Mascle, J.; Ondreas, Helene; Thouement, M.; Gontharet, S.; Stadnitskaia, A.; Pierre, C.; Bayon, Germain; Loncke, L.; Boetius, A.; Bouloubassi, I.; De Lange, G.; Caprais, Jean-claude; Fouquet, Yves; Woodside, J.; Dupre, Stephanie. |
| This paper reports the first "in situ" seafloor observations of fluid escape structures in a fault-controlled caldera-type depression of about 8 km diameter, named the Menes caldera, in the Eastern Mediterranean sea off Egypt (western province of the Nile Deep Sea Fan). A detailed analysis of seven Nautile dives, performed during the Nautinil cruise in 2003, focused on determining the nature, origin, importance, mechanisms and environmental impacts of the fluid escape processes from the geological observations. Seafloor maps, constructed from direct visual observations and video records made from the submersible, and sampling results, for three mud volcanoes of the caldera, Cheops, Chephren and Mykerinos show differences in activity but many common... |
| Tipo: Text |
Palavras-chave: Mediterranean Sea; Nile Deep Sea Fan; Mud volcano; Brine seep. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00000/11089/10627.pdf |
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| Bayon, Germain; Loncke, L.; Dupre, Stephanie; Caprais, Jean-claude; Ducassou, E.; Duperron, Sebastien; Etoubleau, Joel; Foucher, Jean-paul; Fouquet, Yves; Gontharet, S.; Henderson, G. M.; Huguen, Caroline; Klaucke, I.; Mascle, J.; Migeon, S.; Olu-le-roy, Karine; Ondreas, Helene; Pierre, C.; Sibuet, Myriam; Stadnitskaia, A.; Woodside, J.. |
| We report on a multidisciplinary study of cold seeps explored in the Central Nile deep-sea fan of the Egyptian margin. Our approach combines in situ seafloor observation, geophysics, sedimentological data, measurement of bottom-water methane anomalies, pore-water and sediment geochemistry, and Th-230/U dating of authigenic carbonates. Two areas were investigated, which correspond to different sedimentary provinces. The lower slope, at similar to 2100 m water depth, indicates deformation of sediments by gravitational processes, exhibiting slope-parallel elongated ridges and seafloor depressions. In contrast, the middle slope, at similar to 1650 m water depth, exhibits a series of debris-flow deposits not remobilized by post-depositional gravity processes.... |
| Tipo: Text |
Palavras-chave: Authigenic carbonate; U Th; Cold seep; Continental margin; Nile. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6586.pdf |
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| Registros recuperados: 32 | |
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