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| Registros recuperados: 11 | |
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| Sibuet, Myriam; Vangriesheim, Annick. |
| The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites ranging from 350 to 4800 m water depth inside or near the channel and away from its influence. Ifremer conducted eight deep-sea cruises on board research vessels between 2000 and 2005. Standardized methods of sampling together with new technologies such as the ROV... |
| Tipo: Text |
Palavras-chave: Cold coral; Cold seep communities; Benthos diversity; Turbidity current; Congo canyon; Gulf of Guinea. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7349.pdf |
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| Babonneau, Nathalie; Delacourt, Christophe; Cancouet, R.; Sisavath, Emmanuelle; Bachelery, Patrick; Mazuel, Aude; Jorry, Stephan; Deschamps, Anne; Ammann, Jerome; Villeneuve, N.. |
| Submarine canyon heads are key areas for understanding the triggering factors of gravity currents responsible for the transfer of detrital sediment to the deep basins. This contribution offers a detailed picture of canyon heads off La Réunion Island, with high-resolution multibeam bathymetry in the water depth range of 4–220 m. The present feeding of the Cilaos turbidite system, one of the largest modern volcaniclastic systems in the world, is deduced from morphological and sedimentological interpretations of newly acquired data. The study highlights small-scale sedimentary features indicating hydrodynamic and sedimentary processes. A direct connexion between the Saint-Etienne river mouth and submarine canyons is evidenced by the complete incision of the... |
| Tipo: Text |
Palavras-chave: Submarine canyon; Canyon head; Turbidity current; Hyperpycnal flow; Coastal instability. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26697/24790.pdf |
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| Mas, Virginie; Mulder, T.; Dennielou, Bernard; Schmidt, S.; Khripounoff, Alexis; Savoye, Bruno. |
| The Var turbidite system is a small sandy system located in the Ligurian Basin (Mediterranean Sea). It is active during present sea-level highstand and shows four types of sediment transfer processes: (1) low-density turbidity surges generated by small-scale failures (2) low-magnitude, high-frequency (yearly) hyperpycnal turbid plumes, (3) high-magnitude, less-frequent, hyperpycnal currents and (4) high-magnitude flows generated by large slope failures. These processes have different imprints on the morphology of the system. Inversely, the topography plays a role on the behaviour of these flows. The depositional and erosional architecture of the system has been investigated in detail on the basis of SAR imagery and a set of cores using an interface corer... |
| Tipo: Text |
Palavras-chave: Var; France; Gravity processes; Mediterranean; Turbidity current; Hyperpycnal; Flood. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00013/12458/11862.pdf |
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| Hugot, Alexandre; Joseph, Philippe; Savoye, Bruno; Zaleski, Stéphane. |
| We propose to apply in this note a simple mathematical model for the sedimentation of gravity deposits in deep water. An inverse method has been developed in order to characterize the parameters associated with the submarine flow. This method also provides the initial conditions, which constitute a major uncertainty in geoscience modelling. Application of the inverse method to the 1979 Nice air-port collapse (southern France), constrained by cable breaks and/or deposit thicknesses, leads, for example, to the estimation of the initial volume and/or the physical parameters of the flow (friction coefficient, modified turbulent Schmidt number, etc.). The application of the model to this real case shows that only the simultaneous inversion of dynamic (cable... |
| Tipo: Text |
Palavras-chave: France; 1979 Nice airport collapse; Inverse problem; Flow object; Turbidity current; Gravity flow. |
| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-787.pdf |
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| Cattaneo, Antonio; Babonneau, Nathalie; Ratzov, G.; Dan-unterseh, G.; Yelles, K.; Bracene, R.; De Lepinay, B. Mercier; Boudiaf, A.; Deverchere, Jacques. |
| Shaking by moderate to large earthquakes in the Mediterranean Sea has proved in the past to potentially trigger catastrophic sediment collapse and flow. On 21 May 2003, a magnitude 6.8 earthquake located near BoumerdSs (central Algerian coast) triggered large turbidity currents responsible for 29 submarine cable breaks at the foot of the continental slope over similar to similar to 150 km from west to east. Seafloor bathymetry and backscatter imagery show the potential imprints of the 2003 event and of previous events. Large slope scarps resulting from active deformation may locally enhance sediment instabilities, although faults are not directly visible at the seafloor. Erosion is evident at the foot of the margin and along the paths of the numerous... |
| Tipo: Text |
Palavras-chave: Western mediterranean sea; Cascadia subduction zone; Turbidity current; Zemmouri earthquake; Sedimentary processes; Submarine landslides; Northern algeria; Margin; Gps; Boundary. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00098/20959/18571.pdf |
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| Miramontes, Elda; Penven, Pierrick; Fierens, Ruth; Droz, Laurence; Toucanne, Samuel; Jorry, Stephan; Jouet, Gwenael; Pastor, Lucie; Silva Jacinto, Ricardo; Gaillot, Arnaud; Giraudeau, Jacques; Raisson, François. |
| Mixed turbidite-contourite systems can be found in oceans where bottom currents and turbidity currents interact. The Zambezi turbidite system, located in the Mozambique Channel (SW Indian Ocean), is one of the largest sedimentary systems in the world in length and area of the related catchments. The oceanic circulation in the Mozambique Channel is intense and complex, dominated by eddies flowing southwards and deep currents flowing northwards along the Mozambican margin. Current measurements obtained from moorings at 3400–4050 m water depth in the Zambezi and Tsiribihina valleys show periods of intense currents at the seafloor with peaks of 40–50 cm s−1 that last up to one month and are not related to turbidity currents. These strong bottom-current events... |
| Tipo: Text |
Palavras-chave: Contourite; Turbidity current; Mixed system; Oceanic circulation; Mooring; ADCP; ROMS model; Bedform. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00476/58743/61269.pdf |
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| Mulder, Thierry; Lecroart, P; Hanquiez, V; Marches, E; Gonthier, E; Guedes, J; Thiebot, E; Jaaidi, B; Kenyon, N; Voisset, Michel; Perez, C; Sayago, M; Fuchey, Y; Bujan, S. |
| Recent multibeam bathymetry and acoustic imagery data provide a new understanding of the morphology of the western part of the Gulf of Cadiz. The gulf is under the influence of a strong current, the Mediterranean Outflow Water (MOW). This current is at the origin of the construction of the giant Contourite Depositional System. Canyons and valleys with erosive flanks are observed. Only the Portimao Canyon is presently connected to the continental shelf. Channels occur on the continental shelf but are presently disconnected from the deeper network of channels and valleys. Slumps are localized in steep slope areas. They are caused by oversteepening and overloading, sometimes probably associated with earthquake activity. Slumps transform sharply into turbidity... |
| Tipo: Text |
Palavras-chave: Contour current; Interaction; Turbidity current; Geomorphology; Gulf of Cadiz. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1718.pdf |
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| Registros recuperados: 11 | |
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