|
|
|
| Registros recuperados: 17 | |
|
| |
|
|
| Marcon, Yann; Sahling, Heiko; Allais, Anne-gaelle; Bohrmann, Gerhard; Olu, Karine. |
| The Regab pockmark is a large cold seep area located 10 km north of the Congo deep sea channel at about 3160 m water depth. The associated ecosystem hosts abundant fauna, dominated by chemosynthetic species such as the mussel Bathymodiolus aff. boomerang, vestimentiferan tubeworm Escarpia southwardae, and vesicomyid clams Laubiericoncha chuni and Christineconcha regab. The pockmark was visited during the West African Cold Seeps (WACS) cruise with RV Pourquoi Pas? in February 2011, and a 14,000-m2 high-resolution videomosaic was constructed to map the most populated area and to describe the distribution of the dominant megafauna (mussels, tubeworms and clams). The results are compared with previous published works, which also included a videomosaic in the... |
| Tipo: Text |
Palavras-chave: Cold seep; Fauna; Mosaic; Pockmark; Regab; Temporal variation. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00144/25528/23765.pdf |
| |
|
|
| Lazar, Cassandre Sara. |
| A large portion of the greenhouse gas methane on Earth is trapped in marine sediments. However, little methane actually reaches the hydrsphere and the atmosphere, because it is efficiently consumed by anaerobic methane-oxidizing Archaea (ANME). This methane is mainly biogenic in marine sédiments, and is produced by methanogenic Archaea. Methane ascends from deep sources to the seabed, in cold seep sites of continental margins. In order to study microbial community diversity in cold seeps, and to determine geochemical factors that control these microbial communities, we compared four geochemically and geologically distinct sites. In this work, molecular tools (PCR, RT-PCR, DGGE, cloning) as well as genetic markers (16S rRNA, mcrA, dsrB) were employed, to... |
| Tipo: Text |
Palavras-chave: Diversité moléculaire; Archaea; Méthanogène; ANME; McrA; DsrB; DGGE; Volcan de boue; Pockmark; Saumures; Fluides froids; Méthane; Mer de Norvège; Mer Méditerranée; Sédiments.; Molecular diversity; Archaea; Methanogen; ANME; McrA; DsrB; DGGE; Mud volcano; Pockmark; Brines; Cold seep; Methane; Norwegian Sea; Mediterranean Sea; Sediments.. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00031/14250/11534.pdf |
| |
|
|
| 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 |
| |
|
|
| Decker, Carole; Olu, Karine. |
| The Hakon Mosby mud volcano (HMMV) is one of the most studied cold-seep sites in Europe. Its exceptional fluid expulsion activity and large geochemical gradients from the centre to the periphery support dense biological communities and induce spatial heterogeneity in microbial activity and faunal zonation. At this site, the macrofauna has been little studied and the variability in its macrobenthic nutrition has not yet been investigated. In this study, based on the analysis of the stable isotopes of carbon and nitrogen, we determined nutritional patterns for macrofauna communities in three different habitats (microbial mats, sediment adjacent to the mat and Siboglinidae polychaete fields). delta C-13 values of macrofaunal tissues varied among two habitats... |
| Tipo: Text |
Palavras-chave: Cold seep; Hakon Mosby; Macrofaunal nutrition; Stable isotope analysis. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00019/13043/10161.pdf |
| |
|
|
| Mazumdar, A.; Dewangan, P.; Joaeo, H. M.; Peketi, A.; Khosla, V. R.; Kocherla, M.; Badesab, F. K.; Joshi, R. K.; Roxanne, P.; Ramamurty, P. B.; Karisiddaiah, S. M.; Patil, D. J.; Dayal, A. M.; Ramprasad, T.; Hawkesworth, C. J.; Avanzinelli, R.. |
| We report evidence of paleo-cold seep associated activities, preserved in methane-derived carbonates in association with chemosynthetic clams (Calyptogena sp.) from a sediment core in the Krishna-Godavari basin, Bay of Bengal. Visual observations and calculations based on high-resolution wet bulk density profile of a core collected on board R/V Marion Dufresne (May 2007) show zones of sharp increase in carbonate content (10-55 vol%) within 16-20 meters below seafloor (mbsf). The presence of Calyptogena clam shells, chimneys, shell breccias with high Mg calcite cement, and pyrite within this zone suggest seepage of methane and sulfide-bearing fluid to the seafloor in the past. Highly depleted carbon isotopic values (delta(13)C ranges from -41 to -52% VPDB)... |
| Tipo: Text |
Palavras-chave: Methane hydrate; Cold seep; Authigenic carbonate; Bay of Bengal; AMO; Chemosynthetic community. |
| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00218/32911/31414.pdf |
| |
|
|
| Ritt, Benedicte; Sarrazin, Jozee; Caprais, Jean-claude; Noel, Philippe; Gauthier, Olivier; Pierre, Catherine; Henry, Pierre; Desbruyeres, Daniel. |
| A brackish-water cold seep on the North Anatolian Fault (NAF) in the Marmara Sea was investigated with the Nautile submersible during the MarNaut cruise in 2007. This active zone has already been surveyed and revealed evidence of active seeping on the seafloor, such as bubble emissions, patches of reduced sediments, microbial mats and authigenic carbonate crusts. MarNaut was the first opportunity to sample benthic communities in the three most common microhabitats (bioturbated and reduced sediments, carbonate crust) and to examine their relationships with environmental conditions. To do so, faunal communities were sampled and chemical measurements were taken close to the organisms. According to diversity indices, the bioturbated microhabitat exhibited the... |
| Tipo: Text |
Palavras-chave: Marmara Sea; Cold seep; Benthic fauna; Biological diversity; Environmental conditions; Chemosynthetic. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00014/12506/9528.pdf |
| |
|
|
| Olu, Karine; Caprais, Jean-claude; Galeron, Joelle; Causse, R.; Von Cosel, R.; Budzinski, H.; Le Menach, K.; Le Roux, C.; Levache, D.; Khripounoff, Alexis; Sibuet, Myriam. |
| Detailed surveying with an ROV found that a dense and diverse cold-seep community colonises a giant pockmark located at 3200 m depth, 8 km north from the deep Congo channel. Several types of assemblages, either dominated by Mytilidae and Vesicomyidae bivalves or Siboglinidae polychaetes, are distributed on the 800-m diameter active area. The site is characterised by a most active central zone in a depression with abundant carbonate concretions and high methane fluxes where high-density clusters of mussels and siboglinids dominate. In contrast, the peripheral zones display large fields of dead and live vesicomyids on soft sediment, with a lower mean density and lower methane concentration in seawater. The associated megafauna includes Alvinocarididae... |
| Tipo: Text |
Palavras-chave: Congo Angola margin; Atlantic Equatorial African margin; Vagrant species; Isotopic signature; Megafauna; Cold seep. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7478.pdf |
| |
|
|
| 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 |
| |
|
|
| Baldrighi, Elisa; Vanreusel, A.; Zeppilli, Daniela; Sandulli, R.; Segonzac, Michel. |
| Several individuals belonging to a new species of the genus Chromadorita (Nematoda: Adenophorea) were collected in a cold-seep area in the Gulf of Guinea during two French cruises: BIOZAIRE 2 (2001) and BIOZAIRE 3 (2003-2004) on board the R/V L'Atalante. In this area, rich chemosynthetic benthic communities have been discovered at 3150 m depth in the large pockmark field named Regab. Chromadorita regabi sp. nov. was found among the eggs in ovigerous specimens of the shrimp Alvinocaris muricola. The combination of long size (1500-2200 mu m), nine strong preanal papillae and relatively small dorsal tooth with weak musculature distinguishes this species from all known congeneric ones. An identification key to all known species of Chromadorita is provided. |
| Tipo: Text |
Palavras-chave: Chromadorita regabi; Cold seep; Gulf of Guinea; Alvinocaris muricola. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00454/56599/58271.pdf |
| |
|
|
| Russ, Lina; Kartal, Boran; Op Den Camp, Huub J. M.; Sollai, Martina; Le Bruchec, Julie; Caprais, Jean-claude; Godfroy, Anne; Damste, Jaap S. Sinninghe; Jetten, Mike S. M.. |
| Hydrothermally active sediments are highly productive, chemosynthetic areas which are characterized by the rapid turnover of particulate organic matter under extreme conditions in which ammonia is liberated. These systems might be suitable habitats for anaerobic ammonium oxidizing (anammox) bacteria but this has not been investigated in detail. Here we report the diversity and abundance of anammox bacteria in sediments that seep cold hydrocarbon-rich fluids and hydrothermal vent areas of the Guaymas Basin in the Cortes Sea using the unique functional anammox marker gene, hydrazine synthase (hzsA). All clones retrieved were closely associated to the "Candidatus Scalindua" genus. Phylogenetic analysis revealed two distinct clusters of hzsA sequences (Ca.... |
| Tipo: Text |
Palavras-chave: Anammox; HzsA; AprA; Hydrothermal vents; Cold seep; Sulfide. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00180/29156/27555.pdf |
| |
|
|
| 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 |
| |
|
|
| 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 |
| |
|
|
| Cordes, Erik E.; Cunha, Marina R.; Galeron, Joelle; Mora, Camilo; Olu-le Roy, Karine; Sibuet, Myriam; Van Gaever, Saskia; Vanreusel, Ann; Levin, Lisa A.. |
| Cold seeps are among the most heterogeneous of all continental margin habitats. Abiotic Sources of heterogeneity in these systems include local variability in fluid flow, geochemistry, and substrate type, which give rise to different sets of microbial communities, microbial symbiont-bearing foundation species, and associated heterotrophic species. Biogenic habitats created by microbial mats and the symbiotic species including vesicomyid clams, bathymodiolin mussels, and siboglinid tubeworms add an additional layer of complexity to seep habitats. These forms of habitat heterogeneity result in a variety of macrofaunal and meiofaunal communities that respond to changes in structural complexity, habitat geochemistry, nutrient sources, and interspecific... |
| Tipo: Text |
Palavras-chave: Beta diversity; Chemosynthetic communities; Cold seep; Continental margin; Macrofauna; Meiofauna; Metacommunity; Species accumulation. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00002/11281/7826.pdf |
| |
|
|
| Storh, Sabine; Segonzac, Michel. |
| Prior to this study, two species of ophiuroid had been described from hydrothermal vent sites, and another from methane cold seeps, all from the Atlantic Ocean. Although ophiuroids have occasionally been reported from vents in the Pacific Ocean as well, none has been described before. This study presents two new species, Spinophiura jolliveti gen. et sp. nov., family Ophiuridae, and Ophiolamina eprae gen. et sp. nov., family Ophiacanthidae, which are most likely endemic to reducing environments in the East Pacific. We also include detailed descriptions of the post-metamorphic development of these species. Spinophiura jolliveti is characterized by up to five rather long, semi-erect arm spines and a relatively small oral shield. Its postlarva is unusual in... |
| Tipo: Text |
Palavras-chave: Cold seep; Hydrothermal vent; Taxonomy; Morphology; SEM; Ophiacanthidae; Ophiuridae; Postlarval development; Brittle stars. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-6475.pdf |
| |
|
| |
|
|
| Wang, Xudong; Li, Niu; Feng, Dong; Hu, Yu; Bayon, Germain; Liang, Qianyong; Tong, Hongpeng; Gong, Shanggui; Tao, Jun; Chen, Duofu. |
| Cold seeps frequently occur at the seafloor along continental margins. The dominant biogeochemical processes at cold seeps are the combined anaerobic oxidation of methane and sulfate reduction, which can significantly impact the global carbon and sulfur cycles. The circulation of methane-rich fluids at margins is highly variable in time and space, and assessing past seepage activity requires the use of specific geochemical markers. In this study, we report multiple sedimentary proxy records for three piston gravity cores (QDN-14A, QDN-14B, and QDN-31) from the Haima seep of the South China Sea (SCS). By combining total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN), total sulfur (TS), acid insoluble carbon and sulfur isotope... |
| Tipo: Text |
Palavras-chave: Cold seep; Anaerobic oxidation of methane; Carbon and sulfur isotopes; South China Sea. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00465/57662/59858.pdf |
| |
| Registros recuperados: 17 | |
|
|
|
