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| Registros recuperados: 58 | |
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| Wheeler, Andrew J.; Beyer, A; Freiwald, A; De Haas, H; Huvenne, V. A. I.; Kozachenko, M; Olu, Karine; Opderbecke, Jan. |
| Cold-water coral carbonate mounds, owing their presence mainly to the framework building coral Lophelia pertusa and the activity of associated organisms, are common along the European margin with their spatial distribution allowing them to be divided into a number of mound provinces. Variation in mound attributes are explored via a series of case studies on mound provinces that have been the most intensely investigated: Belgica, Hovland, Pelagia, Logachev and Norwegian Mounds. Morphological variation between mound provinces is discussed under the premise that mound morphology is an expression of the environmental conditions under which mounds are initiated and grow. Cold-water coral carbonate mounds can be divided into those exhibiting "inherited"... |
| Tipo: Text |
Palavras-chave: Seabed mapping; Environmental setting; Morphology; Cold water coral; Carbonate mound. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2411.pdf |
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| Dennielou, Bernard; Droz, Laurence; Babonneau, Nathalie; Jacq, Celine; Bonnel, Cedric; Picot, Marie; Le Saout, Morgane; Saout, Yohan; Bez, Martine; Savoye, Bruno; Olu, Karine; Rabouille, Christophe. |
| The detailed structure and composition of turbiditic channel-mouth lobes is still largely unknown because they commonly lie at abyssal water depths, are very thin and are therefore beyond the resolution of hull-mound acoustic tools. The morphology, structure and composition of the Congo turbiditic channel-mouth lobe complex (90×40 km; 2525 km2) were investigated with hull-mounted swath bathymetry, air gun seismics, 3.5 kHz sub-bottom profiler, sediment piston cores and also with high-resolution multibeam bathymetry and video acquired with a Remote Operating Vehicle (ROV). The lobe complex lies 760 km off the Congo River mouth in the Angola abyssal plain between 4740 and 5030 m deep. It is active and is fed by turbidity currents that deposit several... |
| Tipo: Text |
Palavras-chave: Congo deep-sea fan; Lobe; Lobe complex; Channel; Channel-Lobe Transition Zone; Angola basin; Slump; Slide; Debrite; Turbidite; ROV; Bathymetry; Seismic; Sediment core. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00378/48976/49383.pdf |
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| Decker, Carole; Olu, Karine; Cunha, Regina L.; Arnaud, Sophie. |
| Vesicomyid bivalves are among the most abundant and diverse symbiotic taxa in chemosynthetic-based ecosystems: more than 100 different vesicomyid species have been described so far. In the present study, we investigated the phylogenetic positioning of recently described vesicomyid species from the Gulf of Guinea and their western Atlantic and Pacific counterparts using mitochondrial DNA sequence data. The maximum-likelihood (ML) tree provided limited support for the recent taxonomic revision of vesicomyids based on morphological criteria; nevertheless, most of the newly sequenced specimens did not cluster with their morphological conspecifics. Moreover, the observed lack of geographic clustering suggests the occurrence of independent radiations followed by... |
| Tipo: Text |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00076/18729/16301.pdf |
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| Decker, Carole; Olu, Karine; Arnaud-haond, Sophie; Duperron, Sebastien. |
| Vesicomyid clams harbor intracellular sulfur-oxidizing bacteria that are predominantly maternally inherited and co-speciate with their hosts. Genome recombination and the occurrence of non-parental strains were recently demonstrated in symbionts. However, mechanisms favoring such events remain to be identified. In this study, we investigated symbionts in two phylogenetically distant vesicomyid species, Christineconcha regab and Laubiericoncha chuni, which sometimes co-occur at a cold-seep site in the Gulf of Guinea. We showed that each of the two species harbored a single dominant bacterial symbiont strain. However, for both vesicomyid species, the symbiont from the other species was occasionally detected in the gills using fluorescence in situ... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00153/26427/24527.pdf |
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| Ondreas, Helene; Olu, Karine; Fouquet, Yves; Charlou, Jean-luc; Gay, Aurelien; Dennielou, Bernard; Donval, Jean-pierre; Fifis, Alexis; Nadalig, Thierry; Cochonat, Pierre; Cauquil, E; Bourillet, Jean-francois; Le Moigne, Morgan; Sibuet, Myriam. |
| A giant, 800-m wide pockmark, called Regab, was discovered along the Equatorial African margin at 3160-m water depth and was explored by remote operated vehicle (ROV) as part of the Zaiango (1998-2000) and Biozaire (2001-2003) projects carried out conjointly by TOTAL and a number of French research institutes. A microbathymetric map obtained using the ROV sensors shows that the pockmark actually consists of a cluster of smaller pockmarks aligned N70 along a 15-m deep depression. Methane was recorded all over the pockmark, the highest values along the axis of the depression where massive carbonate crusts and dense seep communities were also found. Several faunal species belong to the Vesicomyidae and Mytilidae bivalve families, as well as to Siboglinidae... |
| Tipo: Text |
Palavras-chave: Gabon; Microbathymetric map; ROV; Exploration; Pockmark; Equatorial African margin. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-1239.pdf |
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| Dupre, Stephanie; Woodside, J; Foucher, Jean-paul; De Lange, G; Mascle, J; Boetius, A; Mastalerz, V; Stadnitskaia, A; Ondreas, Helene; Huguen, C; Harmegnies, Francois; Gontharet, Swanne; Loncke, L; Deville, E; Niemann, H; Omoregie, E; Olu, Karine; Fiala Medioni, A; Dahlmann, A; Caprais, Jean-claude; Prinzhofer, A; Sibuet, Myriam; Pierre, C; Damste, J. |
| Four mud volcanoes of several kilometres diameter named Amon, Osiris, Isis, and North Alex and located above gas chimneys on the Central Nile Deep Sea Fan, were investigated for the first time with the submersible Nautile. One of the objectives was to characterize the seafloor morphology and the seepage activity across the mud volcanoes. The seepage activity was dominated by emissions of methane and heavier hydrocarbons associated with a major thermal contribution. The most active parts of the mud volcanoes were highly gas-saturated (methane concentrations in the water and in the sediments, respectively, of several hundreds of nmol/L and several mmol/L of wet sediment) and associated with significantly high thermal gradients (at 10 m below the seafloor,... |
| Tipo: Text |
Palavras-chave: Seafloor morphology; Methane; Authigenic carbonate precipitation; Gas chimneys; Mud breccia; Mud volcanoes; Fluid seepage; Nile fan. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-4455.pdf |
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| Marsac, Francis; Galletti, Florence; Ternon, Jean-francois; Romanov, Evgeny V.; Demarcq, Herve; Corbari, Laure; Bouchet, Philippe; Roest, Walter; Jorry, Stephan; Olu, Karine; Loncke, Lies; Roberts, Michael J.; Ménard, Frédéric. |
| There is a growing interest in the management of seamounts of the South Western Indian Ocean (SWIO) both in waters under national jurisdictions and in the Areas Beyond National Jurisdiction (ABNJ). On the one hand, new scientific knowledge has been gathered through various oceanographic cruises during the past decade and, on the other hand, new agreements are under consideration globally to promote conservation and sustainable use of the biodiversity in the ABNJ, where the deep sea ecosystems associated to seamounts are a growing matter of concern. SWIO seamounts have attracted interests from fishing operators since the 1960s, while mining exploration contracts have been recently granted. Seamounts are known to shelter rich, fragile and poorly resilient... |
| Tipo: Text |
Palavras-chave: International Law of the Sea; Vulnerable Marine Ecosystems; Deep-sea fisheries; Deep-sea mining; Benthic biodiversity; Saya de Malha Bank; South Indian Ocean Fisheries Agreement; Areas Beyond National Jurisdiction; Amended Nairobi Convention; Marine protected areas. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00598/71049/69362.pdf |
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| Menot, Lenaick; Galeron, Joelle; Olu, Karine; Caprais, Jean-claude; Crassous, Philippe; Khripounoff, Alexis; Sibuet, Myriam. |
| The structure and familial-level composition of macrofaunal communities were examined within and at distance from the giant pockmark Regab in the Southern Gulf of Guinea, at 3200 m depth. The two main questions addressed in this study were (i) does habitat partitioning by large symbiont-bearing taxa. influence macrofaunal assemblages and their environment? and (ii) to what extent does the chemosynthesis-based ecosystem influence the structure and the composition of nearby macrobenthic communities? Along two radials, at sites from 250 to 1000 m away from the active centre of the cold seep, the abundance and composition of the macrofauna were typical of a deep-sea community at that depth. Except for a few cores sampled in or near dead vesicomyid fields at... |
| Tipo: Text |
Palavras-chave: Cold seep; Diversity; Gulf of Guinea; Habitat heterogeneity; Macrofauna; Open slope; Siboglinid tubeworms; Vesicomyid clams. |
| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00002/11282/8099.pdf |
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| Rabouille, C.; Olu, Karine; Baudin, F.; Khripounoff, Alexis; Dennielou, Bernard; Arnaud-haond, Sophie; Babonneau, Nathalie; Bayle, Christophe; Beckler, J.; Bessette, Sandrine; Bombled, B.; Bourgeois, S.; Brandily, Christophe; Caprais, Jean-claude; Cathalot, Cecile; Charlier, K.; Corvaisier, R.; Croguennec, Chantal; Cruaud, Perrine; Decker, Carole; Droz, L.; Gayet, Nicolas; Godfroy, Anne; Hourdez, S.; Le Bruchec, J.; Saout, Johan; Le Saout, Marie-helene; Lesongeur, Francoise; Martinez, P.; Mejanelle, L.; Michalopoulos, P.; Mouchel, Olivier; Noel, Philippe; Pastor, Lucie; Picot, M.; Pignet, Patricia; Pozzato, L.; Pruski, A. M.; Rabiller, Manuella; Raimonet, M.; Ragueneau, O.; Reyss, J. L.; Rodier, Philippe; Ruesch, Blandine; Ruffine, Livio; Savignac, F.; Senyarich, C.; Schnyder, J.; Sen, Arunima; Stetten, E.; Sun, Ming Yi; Taillefert, M.; Teixeira, S.; Tisnerat-laborde, N.; Toffin, Laurent; Tourolle, Julie; Toussaint, F.; Vetion, G.; Jouanneau, J. M.; Bez, M.. |
| The presently active region of the Congo deep-sea fan (around 330 000 km2), called the terminal lobes or lobe complex, covers an area of 2500 km2 at 4700–5100 m water depth and 750–800 km offshore. It is a unique sedimentary area in the world ocean fed by a submarine canyon and a channel-levee system which presently deliver large amounts of organic carbon originating from the Congo River by turbidity currents. This particularity is due to the deep incision of the shelf by the Congo canyon, up to 30 km into the estuary, which funnels the Congo River sediments into the deep-sea. The connection between the river and the canyon is unique for major world rivers. In 2011, two cruises (WACS leg 2 and Congolobe) were conducted to simultaneously investigate the... |
| Tipo: Text |
Palavras-chave: Chemosynthetic habitats; Congo deep-sea fan; Fine sediment; Sedimentation rate; Seafloor morphology; Turbidite; Vesicomyidae. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00335/44580/44298.pdf |
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| Reveillaud, J; Freiwald, A; Van Rooij, D; Le Guilloux, Erwan; Altuna, A; Foubert, A; Vanreusel, A; Olu, Karine; Henriet, J. |
| Studies on the distribution of scleractinian corals in the Bay of Biscay were relatively numerous during the nineteenth and the first half of the twentieth century. Yet, recent reports are scattered, sometimes unpublished, and therefore knowledge about the current coral occurrence in the area is limited. This study aims at compiling the available historical and more recently collected information on the occurrence of scleractinian corals in the Bay of Biscay. Data from two recent cruises are included and compared with previous explored coral sites from as early as 1830 up to 1995. A database of 347 records including 34 described species of scleractinians highlights that the slope of the Bay of Biscay is an important habitat for scleractinians. This could... |
| Tipo: Text |
Palavras-chave: Biodiversity; Bay of Biscay; Slope; Scleractinia; Cold water corals. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4503.pdf |
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| Menot, Lenaick; Van Den Beld, Inge; Arnaud-haond, Sophie; Bourillet, Jean-francois; Davies, J.s.; Guillaumont, Brigitte; Olu, Karine. |
| In the Bay of Biscay, Cold Water Coral (CWC) habitats have been mapped in 24 out of a hundred known submarine canyons. The footprint of ROV or towed-camera transects is small compared to the size of these canyons but still, known CWC habitats totalize a linear of 46 km. The distribution of these habitats, dominated by reef-building scleractinians, antipatharians, alcyonaceans and pennatulids, is however patchy and their median size is small, ranging from 6 to 65 m. While the preservation of these Vulnerable Marine Ecosystems has become essential, all CWC habitats will not be benefit from conservation strategies due to their widespread and patchy distribution. Priorities must thus be defined. Among the criteria for such prioritization, we explore here the... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00469/58077/60484.pdf |
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| Huvenne, Veerle A. I.; Bailey, W. R.; Shannon, P. M.; Naeth, J; Di Primio, R.; Henriet, J. P.; Horsfield, B.; De Haas, H.; Wheeler, A; Olu, Karine. |
| The Magellan mound province is one of the three known provinces of carbonate mounds or cold-water coral banks in the Porcupine Seabight, west of Ireland. It has been studied in detail using a large and varied data set: 2D and 3D seismic data, sidescan sonar imagery and video data collected during ROV deployment have been used to describe the mounds in terms of origin, growth processes and burial. The aim of this paper is to present the Magellan mounds and their setting in an integrated, holistic way. More than 1,000 densely spaced and mainly buried mounds have been identified in the area. They all seem to be rooted on one seismic reflection, suggesting a sudden mound start-up. Their size and spatial distribution characteristics are presented, together with... |
| Tipo: Text |
Palavras-chave: Numerical basin modelling; Fault analysis; Mound morphology; Spatial distribution; Porcupine Basin; Cold water corals; Carbonate mounds. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2312.pdf |
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| Wheeler, A. J.; Kozachenko, M.; Henry, L. -a.; Foubert, A.; De Haas, H.; Huvenne, V. A. I.; Masson, D.c.; Olu, Karine. |
| This paper presents a comprehensive overview of the Moira Mounds in the Porcupine Seabight, combining a review of currently published material with new data and interpretations. The Moira Mounds are circular to ovoid-shaped individual or clustered coral banks (referred to as "scleractinian spaced cluster macroreefs") located in the Belgica (carbonate) mound province, Porcupine Seabight, west of Ireland. They are up to 10 m high and 20 to 35 m in diameter. For the first time, a map showing the complete extent and location of the Moira Mounds is published, revealing 256 examples grouped into four areas mainly between 800 and 1100 m water depth. ROV groundtruthing revealed the importance of bedload sand transport in Moira Mound formation and development... |
| Tipo: Text |
Palavras-chave: Cold-water coral; Coral carbonate mound; Benthic processes; Biogeological processes; Marine geology; NE Atlantic. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00035/14633/12050.pdf |
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| Sen, Arunima; Ondreas, Helene; Gaillot, Arnaud; Marcon, Yann; Augustin, Jean-marie; Olu, Karine. |
| Deep-sea ecosystems have attracted considerable commercial interest in recent years because of their potential to sustain a diverse range of mankind's industrial needs. If these systems are to be preserved or exploited in a sustainable manner, mapping habitats and species distributions is critical. As biodiversity at cold-seeps or other deep-sea ecosystems is driven by habitat heterogeneity, imagery is the obvious choice for characterizing these systems and has indeed proven extremely valuable towards mapping biogenic habitats formed by dense aggregations of large sized species, such as coral reefs, tubeworm bushes or bivalve beds. However, the acquisition of detailed images with resolution sufficient for reliable identification is extremely time... |
| Tipo: Text |
Palavras-chave: Mapping; Cold seeps; Multibeam; Bathymetry; Backscatter; Biogenic habitats. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00312/42286/41612.pdf |
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| Guillon, Erwan; Menot, Lenaick; Decker, Carole; Krylova, Elena; Olu, Karine. |
| The high biodiversity found at cold seeps, despite elevated concentrations of methane and hydrogen sulfide, is attributed to multiple sources of habitat heterogeneity. In addition to geological and geochemical processes, biogenic habitats formed by large symbiont-bearing taxa, such as bivalves and siboglinid tubeworms, or by microbial mats drive the biodiversity of small-sized fauna. However, because these habitat-forming species also depend on geochemical gradients, the respective influence of abiotic and biotic factors in structuring associated macrofaunal communities is often unresolved. The giant pockmark Regab located at 3200 m depth on the Congo margin is characterized by different fluid-flow regimes, providing a mosaic of the most common biogenic... |
| Tipo: Text |
Palavras-chave: Cold-seep; Macrofauna; Diversity; Dynamics; Vesicomyid clams; Gulf of Guinea. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00361/47210/47165.pdf |
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| De Mol, Ben; Kozachenko, M; Wheeler, Andy; Alvares, Hugo; Henriet, Jean-pierre; Olu, Karine. |
| High-resolution seismic profiles, swath bathymetry, side-scan sonar data and video imageries are analysed in this detailed study of five carbonate mounds from the Belgica mound province with special emphasis on the well-surveyed Therese Mound. The selected mounds are located in the deepest part of the Belgica mound province at water depths of 950 m. Seismic data illustrate that the underlying geology is characterised by drift sedimentation in a general northerly flowing current regime. Sigmoidal sediment bodies create local slope breaks on the most recent local erosional surface, which act as the mound base. No preferential mound substratum is observed, neither is there any indication for deep geological controls on coral bank development. Seismic evidence... |
| Tipo: Text |
Palavras-chave: Carbonate mounds; Cold water corals; Lophelia pertusa; Porcupine Seabight; Coral banks; Belgica mound province; Therese Mound. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2307.pdf |
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| Carlier, A.; Le Guilloux, E.; Olu, Karine; Sarrazin, Jozee; Mastrototaro, F.; Taviani, M.; Clavier, J.. |
| Cold-water corals (CWC) are frequently reported from deep sites with locally accelerated currents that enhance seabed food particle supply. Moreover, zooplankton likely account for ecologically important prey items, but their contribution to CWC diet remains unquantified. We investigated the benthic food web structure of the recently discovered Santa Maria di Leuca (SML) CWC province (300 to 1100 m depth) located in the oligotrophic northern Ionian Sea. We analyzed stable isotopes (delta C-13 and delta N-15) of the main consumers (including ubiquitous CWC species) exhibiting different feeding strategies, zooplankton, suspended particulate organic matter (POM) and sedimented organic matter (SOM). Zooplankton and POM were collected 3 m above the coral... |
| Tipo: Text |
Palavras-chave: Particulate organic matter; Zooplankton; Stable isotopes; Food web; Mediterranean Sea; Benthic community; Cold water corals. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7450.pdf |
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| Khripounoff, Alexis; Caprais, Jean-claude; Decker, Carole; Essirard, Mikael; Le Bruchec, Julie; Noel, Philippe; Olu, Karine. |
| We have studied two species of vesicomyid bivalves inhabiting different areas of sulfide-rich sediments in association with methane seepage at two pockmarks located at about 650 m and 3150 m depth, respectively, along the Gabon-Congo margin, and organic-rich sediments in the deepest zone (4950 m depth) of the Congo deep-sea fan. Benthic chambers Calmar were deployed on three study sites to assess gas and solute exchanges at the water-sediment interface. We recorded in situ measurements of oxygen, total carbon dioxide, ammonium, methane, and sulfide in two clam beds at each site. At all sites, irrespective of which the vesicomyid species are present, oxygen consumption was high and variable (28–433 mmol m−2 d−1) as was total carbon dioxide emission (36–1857... |
| Tipo: Text |
Palavras-chave: Benthic chamber; Cold-seep ecosystem; Reduced sediment; Gas fluxes; Vesicomyid bivalves; Gulf of Guinea. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00226/33746/32160.pdf |
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| Registros recuperados: 58 | |
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