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| Registros recuperados: 67 | |
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| Bayon, Germain; Henderson, Gideon M.; Etoubleau, Joel; Caprais, Jean-claude; Ruffine, Livio; Marsset, Tania; Dennielou, Bernard; Cauquil, Eric; Voisset, Michel; Sultan, Nabil. |
| The application of uranium-thorium dating methods to authigenic carbonates provides unique constraints on the temporal evolution of methane seeps at ocean margins. In this study, we report U-Th isotope measurements for carbonate breccias collected from within a hydrate-bearing pockmark located at the Niger Delta margin. These concretions were extracted from a carbonate-rich layer in the upper two meters of a sediment core (N2-KS-44; ~ 1200 m water depth), well above the present-day sulphate-methane transition zone (about 3 m depth) and the presence of gas hydrates in the sediment. The stratigraphy of core N2-KS-44 was established by tuning its downcore Al/Ti profile to a well-dated nearby reference core, and carbonate 230Th/U ages were calculated using... |
| Tipo: Text |
Palavras-chave: Gas hydrates; Pockmarks; U-series; Authigenic carbonates; Niger delta. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00286/39708/41518.pdf |
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| Decker, Carole; Zorn, N.; Le Bruchec, J.; Caprais, Jean-claude; Potier, N.; Leize-wagner, E.; Lallier, F. H.; Olu, Karine; Andersen, A. C.. |
| Vesicomyids live in endosymbiosis with sulfur-oxidizing bacteria and therefore need hydrogen sulfide to survive. They can nevertheless live in a wide range of sulfide and oxygen levels and depths, which may explain the exceptional diversity of this clam family in deep-sea habitats. In the Gulf of Guinea, nine species of vesicomyid clams are known to live in cold-seep areas with pockmarks from 600 to 3200 m deep, as well as in the organic-rich sediments of the Congo deep-sea fan at 5000 m deep. Our previous study showed that two species living in a giant pockmark have different oxygen carriers, suggesting different adaptations to hypoxia. Here, we studied the hemoglobin structure and oxygen affinity in three other species, Calyptogena valdiviae, Elenaconcha... |
| Tipo: Text |
Palavras-chave: Hemoglobin; Mass spectrometry; Oxygen affinity; Symbiont-bearing bivalve; Blood-clams; Cold seeps; Sulfide-rich sediments. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00358/46961/46875.pdf |
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| Olu, Karine; Decker, Carole; Pastor, Lucie; Caprais, Jean-claude; Khripounoff, Alexis; Morineaux, Marie; Ain Baziz, M.; Menot, Lenaick; Rabouille, C.. |
| Methane-rich fluids arising from organic matter diagenesis in deep sediment layers sustain chemosynthesis-based ecosystems along continental margins. This type of cold seep develops on pockmarks along the Congo margin, where fluids migrate from deep-buried paleo-channels of the Congo River, acting as reservoirs. Similar ecosystems based on shallow methane production occur in the terminal lobes of the present-day Congo deep-sea fan, which is supplied by huge quantities of primarily terrestrial material carried by turbiditic currents along the 800 km channel, and deposited at depths of up to nearly 5000 m. In this paper, we explore the effect of this carbon enrichment of deep-sea sediments on benthic macrofauna, along the prograding lobes fed by the current... |
| Tipo: Text |
Palavras-chave: Chemosynthesis-based ecosystems; Cold seeps; Organic rich sediments; Macrofaunal communities. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00384/49561/50053.pdf |
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| Shillito, B; Le Bris, Nadine; Hourdez, S; Ravaux, J; Cottin, D; Caprais, Jean-claude; Jollivet, D; Gaill, F. |
| The shrimp Mirocaris fortunata is a hydrothermal vent species that is found at most vent-sites along the Mid-Atlantic Ridge. This endemic species is found across a hydrothermal gradient, with thermal conditions ranging from 2-9 degrees C in ambient seawater to fairly warm values of about 25 degrees C. We performed in vivo experiments on M. fortunata specimens originating from different sites and depths (850 m to 2300 m), both at atmospheric pressure and in pressurized aquaria, to characterise the upper thermal limits of this species. Atmospheric pressure results show that thermal physiology should be studied at each population's native pressure. At in situ pressure, shrimps from Menez Gwen (850 m depth) and Lucky Strike (1700 m depth) do not survive... |
| Tipo: Text |
Palavras-chave: IPOCAMP TM; Crustacea; Mirocaris fortunata; Thermal stress; Hydrothermal vent. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1240.pdf |
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| Dubois, Stanislas; Derian, Francois; Caisey, Xavier; Rigolet, Carinne; Caprais, Jean-claude; Thiebaut, Eric. |
| We used existing bathymetric data to study the macrofauna of a geophysical pockmark field restricted to a benthic habitat engineered by the tubiculous amphipod Haploops nirae in South Brittany (France). Stations inside and outside pockmarks of different morphometric characteristics (location, size, depression depth) were sampled for macrofauna and environmental parameters (sediment characteristics, organic matter, chl a, hydrogen sulfide and methane concentrations). Diversity indices showed higher species richness inside pockmarks, especially for species with medium to high abundances. Most sediment cores showed low methane but high hydrogen sulfide concentrations. We hypothesised that after eruption, the remaining residual methane from pockmark sediments... |
| Tipo: Text |
Palavras-chave: Benthic habitat; Biodiversity; Succession; Amphipod; Haploops; South Brittany; Sulfide; Methane; Environmental factors. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00272/38333/36576.pdf |
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| Rabouille, C.; Caprais, Jean-claude; Lansard, B.; Crassous, Philippe; Dedieu, K.; Reyss, J. L.; Khripounoff, Alexis. |
| A study of organic carbon mineralization from the Congo continental shelf to the abyssal plain through the Congo submarine channel and Angola Margin was undertaken using in situ measurements of sediment oxygen demand as a tracer of benthic carbon recycling. Two measurement techniques were coupled on a single autonomous platform: in situ benthic chambers and microelectrodes, which provided total and diffusive oxygen uptake as well as oxygen microdistributions in porewaters. In addition, sediment trap fluxes, sediment composition (Org-C, Tot-N, CaCO3, porosity) and radionuclide profiles provided measurements of, respectively input fluxes and burial rate of organic and inorganic compounds. The in situ results show that the oxygen consumption on this margin... |
| Tipo: Text |
Palavras-chave: Sediment carbon budget; Organic carbon burial; Congo Submarine Canyon; Organic carbon recycling in sediments; In situ oxygen demand. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7316.pdf |
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| Marchand, Michel; Termonia, M; Caprais, Jean-claude; Wybauw, M. |
| During the French-Mexican cruise 'Guaynaut', carried out in November 1991 in the southern depression of the Guaymas Basin (gulf of California), an actively spreading oceanic basin, various samples were collected by means of the submersible 'Nautile'. The on-line coupling of purge and trap to capillary gas chromatography-mass spectrometry (P/T-GC-MS) has been applied to the analysis of volatile organic compounds (VOC) in water, sediments and hydrothermal deposit samples in order to contribute to the characterization of the bacterial microflora activity which is developed on this particular hydrothermal site. The results obtained for alkanes, monoaromatic hydrocarbons and organosulfur compounds lead to successful interpretation in terms of bacterial activity. |
| Tipo: Text |
Palavras-chave: Volatile organic compounds (VOC); Hydrothermalism; Guaymas Basin. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00186/29768/28265.pdf |
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| Loncke, L.; Maillard, A.; Basile, C.; Roest, Walter; Bayon, Germain; Gaullier, V.; Pattier, France; Mercier De Lépinay, Marion; Grall, Celine; Droz, L.; Marsset, Tania; Giresse, P.; Caprais, Jean-claude; Cathalot, Cecile; Graindorge, D.; Heuret, A.; Lebrun, J. F.; Bermell, Sylvain; Marcaillou, B.; Sotin, C.; Hebert, B.; Patriat, Martin; Bassetti, M. A.; Tallobre, Cedric; Buscail, R.; Durrieu De Madron, X.; Bourrin, F.. |
| he IGUANES cruise took place in May 2013 on the R/V L'Atalante along the Demerara passive transform margin off French Guiana and Surinam. Seismic, multibeam and chirp acquisitions were made. Piston cores were collected for pore geochemistry and sedimentology. A mooring was deployed on the sea-bottom for 10 months (temperature, salinity, turbidity and current measurements). This new dataset highlights the lateral variability of the 350 km-long Guiana–Surinam transform margin due to the presence of a releasing bend between two transform segments. The adjacent Demerara Plateau is affected by a 350 km-long giant slide complex. This complex initiated in Cretaceous times and was regularly reactivated until recent times. Since the Miocene, contourite processes... |
| Tipo: Text |
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| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00428/53942/55285.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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| 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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| Vigneron, Adrien; Cruaud, Perrine; Roussel, Erwan; Pignet, Patricia; Caprais, Jean-claude; Callac, Nolwenn; Ciobanu, Maria Cristina; Godfroy, Anne; Cragg, Barry A.; Parkes, John R.; Van Nostrand, Joy D.; He, Zhili; Zhou, Jizhong; Toffin, Laurent. |
| Subsurface sediments of the Sonora Margin (Guaymas Basin), located in proximity of active cold seep sites were explored. The taxonomic and functional diversity of bacterial and archaeal communities were investigated from 1 to 10 meters below the seafloor. Microbial community structure and abundance and distribution of dominant populations were assessed using complementary molecular approaches (Ribosomal Intergenic Spacer Analysis, 16S rRNA libraries and quantitative PCR with an extensive primers set) and correlated to comprehensive geochemical data. Moreover the metabolic potentials and functional traits of the microbial community were also identified using the GeoChip functional gene microarray and metabolic rates. The active microbial community structure... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00203/31408/29801.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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| Sarradin, Pierre-marie; Caprais, Jean-claude; Briand, Patrick; Gaill, Françoise; Shillito, Bruce; Desbruyeres, Daniel. |
| The objective of this study is to describe the chemical and physical environment surrounding the vent organisms at the Genesis site (EPR, 2640 m). The main chimney is colonized by Riftia pachyptila, fishes Zoarcidae and crabs Bythograeidae. The top of the smoker is covered with tubes of polychaetes Alvinellidae, the frontier zone by limpet gastropods. Temperature measurements and water sampling were made on an axis along the chimney. The environment was characterized using relationships between chemical concentrations and temperature to provide a chemo-thermal model of the site. Discrete temperature ranges were 1-1.6 degrees C in sea water, 1.6-10 degrees C among Riftia plumes (up to 25 degrees C at the tube base), 7-91 degrees C close to the alvinellid... |
| Tipo: Text |
Palavras-chave: Hydrothermal ecosystem; Hydrogen sulphide; Carbon dioxide; Temperature. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00186/29764/28200.pdf |
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| Cambon-bonavita, Marie-anne; Nadalig, Thierry; Roussel, Erwan; Delage, Eloise; Duperron, Sebastien; Caprais, Jean-claude; Boetius, A.; Sibuet, Myriam. |
| A giant 800-m-diameter pockmark named REGAB was discovered on the Gabon continental margin actively emitting methane at a water depth of 3200 m. The microbial diversity in sediments from four different assemblages of chemosynthetic organisms, Mytilidae, Vesicomyidae, Sibogliniclae and a bacterial mat, was investigated using comparative 16S rRNA gene sequence analysis. Aggregates of anaerobic methanotrophic archaea (ANME-2) and bacteria of the Desulfosarcina/Desulfococcus cluster were found in all four chemosynthetic habitats. Fluorescence in situ hybridization targeting the ANME-2/Desulfosarcina/Desulfococcus aggregates showed their presence few centimeters (3-5cm) below the surface of sediment. 16S rRNA gene sequences from all known marine ANME groups... |
| Tipo: Text |
Palavras-chave: Microbial phylogeny; Faunal assemblage; Cold seep; Chemosynthetic ecosystems; AOM; REGAB. |
| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/2009/publication-7298.pdf |
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| Khripounoff, Alexis; Caprais, Jean-claude; Decker, Carole; Le Bruchec, J.; Noel, Philippe; Husson, Berengere. |
| We studied bivalves (vesicomyids and mytilids) inhabiting four different areas of high sulfide and methane production: 1) in the Gulf of Guinea, two pockmarks (650 m and 3150 m depth) and one site rich in organic sediments in the deepest zone (4950 m average depth), 2) at the Azores Triple Junction on the Mid-Atlantic Ridge, one hydrothermal site (Lucky Strike vent field, 1700 m depth). Two types of Calmar benthic chambers were deployed, either directly set into the sediment (standard Calmar chamber) or fitted with a tank to isolate organisms from the sediment (modified Calmar chamber), to assess gas and solute exchanges in relation to bivalve bed metabolism. Fluxes of oxygen, total carbon dioxide, ammonium and methane were measured. At the site with... |
| Tipo: Text |
Palavras-chave: Deep-sea; Benthic chamber; Vesicomyid and Mytilid bivalves; Respiration rate; Cold seep; Hydrothermal vent. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00341/45204/44614.pdf |
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| Martin, Jean-louis; Marchand, Michel; Le Guellec, Anne-marie; Caprais, Jean-claude. |
| Analyses of pesticides, polychlorobiphenyls (PCB's) and hydrocarbons have been carried out in sediments and water samples from the bays of Jakarta, Banten and Cilacap. Heavy metals (Hg, Cu, Mn, Zn, Fe, Pb, Cd, Ni, Co and Cr) have been analysed in sediment samples fram the same areas. - Organic pollutants : The results show that for pesticides, PCB and hydrocarbons, in water and in sediments, there is no significant pollution for the bays of Banten, Cilacap and Jakarta. The bay of Banten, where most of the concentrations are under the detection limits, that is ta say 2 ug/kg for the sediment and 2 ng/1 for the sea water, can be considered as a reference area. For total hydrocarbons and DDT, the bays of Cilacap and Jakarta show concentrations which can be... |
| Tipo: Text |
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| Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/00094/20546/18217.pdf |
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| Registros recuperados: 67 | |
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