Consulta: subjectFacets:"Cold seep"
Registros recuperados: 17
Data/hora: 09/06/2024 14:57:36

Using chemical compositions of sediments to constrain methane seepage dynamics: A case study from Haima cold seeps of the South China Sea
Provedor de dados: 5
Autores: 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

Spatial heterogeneity of macrofaunal communities in and near a giant pockmark area in the deep Gulf of Guinea
Provedor de dados: 5
Autores: 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

Presence and diversity of anammox bacteria in cold hydrocarbon-rich seeps and hydrothermal vent sediments of the Guaymas Basin
Provedor de dados: 5
Autores: 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

First insights into the structure and environmental setting of cold-seep communities in the Marmara Sea
Provedor de dados: 5
Autores: 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

Multi-disciplinary investigation of fluid seepage on an unstable margin: The case of the Central Nile deep sea fan
Provedor de dados: 5
Autores: 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

Evidence of paleo-cold seep activity from the Bay of Bengal, offshore India
Provedor de dados: 5
Autores: 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

Understanding the biogeography of chemosynthetic ecosystems
Provedor de dados: 5
Autores: Tyler, Pa; German, Cr; Ramirez-llodra, E; Van Dover, Cl.
ChEss is a recently-funded Census of marine life programme aimed at improving our knowledge of the biogeography of deepwater chemosynthetically driven ecosystems by promoting an international field phase of discovery and exploration. The main objectives are to assess and explain the diversity, distribution and abundance of hydrothermal vent and cold seep species. With the global mid-ocean ridge system extending similar to65000 km, it is unlikely that its entire length would be examined in detail. The ChEss programme proposes to select a limited number of target areas chosen for the discovery of new vents and seeps. The intention is to identify the maximum scientific return that could be achieved from detailed investigation of the minimum number of sites at...
Tipo: Text
Palavras-chave: Biogéographie; Écosystème chémosynthétique; Évent hydrothermal; Suintement froid; Biogeography; Chemosynthetic ecosystems; Hydrothermal vent; Cold seep.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/00322/43306/43042.pdf

Occurrence of Chromadorita regabi sp nov (Nematoda: Adenophorea), a nematode egg predator of Alvinocaris muricola (Crustacea: Decapoda: Caridea: Alvinocarididae) from a deep cold seep area of the Gulf of Guinea
Provedor de dados: 5
Autores: 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

Distribution and temporal variation of mega-fauna at the Regab pockmark (Northern Congo Fan), based on a comparison of videomosaics and geographic information systems analyses
Provedor de dados: 5
Autores: 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

Does macrofaunal nutrition vary among habitats at the Hakon Mosby mud volcano?
Provedor de dados: 5
Autores: 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

Influence of seep emission on the non-symbiont-bearing fauna and vagrant species at an active giant pockmark in the Gulf of Guinea (Congo-Angola margin)
Provedor de dados: 5
Autores: 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

Diversity and distribution of methane-oxidizing microbial communities associated with different faunal assemblages in a giant pockmark of the Gabon continental margin
Provedor de dados: 5
Autores: 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

Deep-sea habitat heterogeneity influence on meiofaunal communities in the Gulf of Guinea
Provedor de dados: 5
Autores: Van Gaever, Saskia; Galeron, Joelle; Sibuet, Myriam; Vanreusel, Ann.
To estimate the degree of spatial heterogeneity of benthic deep-sea communities, we carried out a multiple-scale (from m's to 200km) investigation in the Congo-Angola margins (Equatorial West African margin, 3150-4800 m) in which we examined the metazoan meiofauna at a variety of habitats along the Congo Channel system and in the associated cold seep. We investigate the structure, density, vertical distribution patterns in the sediment and biomass of meiofaunal communities in the Gulf of Guinea and how they are controlled by hydrologic and biogeochemical processes The meiofaunal. communities in the Gulf of Guinea were shaped by heterogeneous conditions on the margin, and reflect the multiple-scale spatial variability that corresponds with the different...
Tipo: Text
Palavras-chave: Gulf of Guinea; Nematodes; Meiofauna; Cold seep; Congo canyon; West equatorial Africa margin deep sea.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-7483.pdf

The influence of geological, geochemical, and biogenic habitat heterogeneity on seep biodiversity
Provedor de dados: 5
Autores: 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

Diversité et activité des communautés microbiennes dans des sédiments marins associés aux émissions de fluides froids
Provedor de dados: 5
Autores: 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

Respiration of bivalves from three different deep-sea areas: cold seeps, hydrothermal vents and organic carbon-rich sediments
Provedor de dados: 5
Autores: 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

Two New Genera and Species of Ophiuroid (Echinodermata) from Hydrothermal Vents in the East Pacific
Provedor de dados: 5
Autores: 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