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Registros recuperados: 62 | |
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Mapstone, Gillian M.; Corbari, Laure; Menot, Lenaick. |
Rhodaliids are a semi-benthic family of 14 physonect siphonophore species found in all oceans, except the Mediterranean and Arctic. They inhabit species-specific depth ranges in isolated locations and records are mostly sparse. Here, the first ever observations of rhodaliids from the Mid-Atlantic Ridge are given, from three images of two putative species. They come from depths of 3482 and 3667–3670 metres, on the Mid-Atlantic Ridge (MAR) at 23°N and 26°N, near two hydrothermal vents. Rhodaliids are very delicate animals and extremely hard to sample, particularly from such great depths, and the only comparable deep-living species so far described is the Galapagos Dandelion (Thermopalia taraxaca) from 2480–2938 metres on the Galapagos Rift and East Pacific... |
Tipo: Text |
Palavras-chave: Deep-sea; Mid-Atlantic Ridge; Rhodaliid; Siphonophore. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00361/47207/51395.pdf |
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Dekov, Vm; Damyanov, Zk; Kamenov, Gd; Bonev, Ik; Rajta, I; Grime, Gw. |
A number of small, irregular-shaped and spherical shiny metallic particles have been found in the sediments from the Mir zone, Trans-Atlantic Geotraverse hydrothermal held (Mid-Atlantic Ridge, 26 degreesN). The phase variety of the particles examined is represented by metallic tin: tin-rich lead, and tin-copper phases. A detailed mineralogical study of these particles was carried out using optical microscopy, nuclear microscopy, scanning electron microscopy, electron microprobe, proton microprobe and X-ray diffraction analysis. Tin-lead grains have the typical eutectic microtexture of the metal components. Tin-copper grains are formed from single crystals of sorosite, eta -Cu6Sn5. The Sn-Pb-Cu complex grains are composed of fine stannoan lead... |
Tipo: Text |
Palavras-chave: Zone hydrothermale; Dorsale médio-Atlantique; Étain et plomb natifs; Sorosite; Hydrothermal field; Mid-Atlantic Ridge; Native Sn and Pb; Sorosite. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/00322/43350/42876.pdf |
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Cuvelier, Daphne; Sarradin, Pierre-marie; Sarrazin, Jozee; Colaco, Ana; Copley, Jon T.; Desbruyeres, Daniel; Glover, Adrian G.; Santos, Ricardo Serrao; Tyler, Paul A.. |
The Eiffel Tower edifice is situated in the Lucky Strike hydrothermal vent field at a mean depth of 1690 m on the Mid-Atlantic Ridge (MAR). At this 11-m-high hydrothermal structure, different faunal assemblages, varying in visibly dominant species (mussels and shrimp), in mussel size and in density of mussel coverage, were sampled biologically and chemically. Temperature and sulphide (Sigma S) were measured on the different types of mussel-based assemblages and on a shrimp-dominated assemblage. Temperature was used as a proxy for calculating total concentrations of CH4. Based on the physico-chemical measurements, two microhabitats were identified, corresponding to (i) a more variable habitat featuring the greatest fluctuations in environmental variables... |
Tipo: Text |
Palavras-chave: Faunal assemblage; Hydrothermal vent; Microhabitat; Mid-Atlantic Ridge; Physico-chemical characterisation. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00035/14648/13996.pdf |
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Lartaud, Franck; De Rafelis, Marc; Oliver, Graham; Krylova, Elena; Dyment, Jerome; Ildefonse, Benoit; Thibaud, Remy; Gente, Pascal; Hoise, Eva; Meistertzheim, Anne-leila; Fouquet, Yves; Gaill, Francoise; Le Bris, Nadine. |
Hydrothermal circulation at ultramafic-hosted sites supports a large variety of high-and low-temperature hydrothermal vents and associated ecosystems. The discovery of abundant fossil vesicomyid and thyasirid shell accumulations at the ridge crest, approximately 2.5 km east of the active Rainbow vent field on the Mid-Atlantic Ridge (MAR, 36 degrees 13'N), increased our knowledge regarding the diversity of vent communities at slow spreading ridges. Bivalve molluscs of the family Vesicomyidae were represented by the genus Phreagena. Here we present the first record of this genus in the Atlantic Ocean. This second vesicomyid species known from the MAR, Phreagena sp., was found to be associated with a Thyasira species that is affiliated with T. southwardae (at... |
Tipo: Text |
Palavras-chave: Ultramafic-hosted; Mid-Atlantic Ridge; Bivalve shells; Vesicomyidae; Thyasiridae; Carbon and oxygen isotopes. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00012/12301/9093.pdf |
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Portail, Marie; Brandily, Christophe; Cathalot, Cecile; Colaco, Ana; Gelinas, Yves; Husson, Berengere; Sarradin, Pierre-marie; Sarrazin, Jozee. |
The assessment and comparison of food webs across various hydrothermal vent sites can enhance our understanding of ecological processes involved in the structure and function of biodiversity. The Menez Gwen, Lucky Strike and Rainbow vent fields are located on the Azores triple junction of the Mid-Atlantic Ridge. These fields have distinct depths (from 850 to 2320 m) and geological contexts (basaltic and ultramafic), but share similar faunal assemblages defined by the presence of foundation species that include Bathymodiolus azoricus, alvinocarid shrimp and gastropods. We compared the food webs of 13 faunal assemblages at these three sites using carbon and nitrogen stable isotope analyses (SIA). Results showed that photosynthesis-derived organic matter is a... |
Tipo: Text |
Palavras-chave: Mid-Atlantic Ridge; Hydrothermal vents; Food webs; Stable isotopes; Functional traits. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00414/52551/53732.pdf |
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Spedicato, Adriana; Sánchez, Nuria; Pastor, Lucie; Menot, Lenaick; Zeppilli, Daniela. |
The risk assessment of seafloor massive sulfide (SMS) mining on meiobenthic organisms, specifically on soft-sediment meiofauna, is impeded by a lack of knowledge on the biology and ecology of these communities. In this study, we investigated sediment samples taken in proximity of active vents at Trans-Atlantic Geotraverse (TAG) and Snake Pit, two hydrothermal vent fields of the Mid-Atlantic Ridge, in order to explore metazoan meiofauna, particularly nematode community, and its relation to organic carbon, total nitrogen, total sulfur, and dissolved oxygen. Organic carbon and nitrogen contents were low at both sites. High concentrations of total sulfur and low oxygen penetration were found at Snake Pit compared to TAG. Snake Pit showed approximately four... |
Tipo: Text |
Palavras-chave: Meiobenthos; Nematoda; Mid-Atlantic Ridge; Seafloor massive sulfides; Biodiversity. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00629/74061/73507.pdf |
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Teixeira, Sara; Cambon-bonavita, Marie-anne; Serrao, Ester A.; Desbruyeres, Daniel; Arnaud-haond, Sophie. |
Aim Deep-sea hydrothermal vents are unstable habitats that are both spatially and temporally fragmented. In vent species, a 'short-term insurance' hypothesis would lead us to expect mostly self-recruitment, limiting the loss of larvae in the deep ocean or water column and increasing genetic differentiation over the time elapsed since colonization. Alternatively, a 'long-term insurance' hypothesis would support the prediction of selection for large-scale dispersal, to ensure long-term persistence in these ephemeral habitats. The main goal of this study was to infer the spatial and temporal distribution of genetic diversity of the shrimp Rimicaris exoculata, which forms high-density local populations on hydrothermal vents along the Mid-Atlantic ridge.... |
Tipo: Text |
Palavras-chave: Bottleneck; Deep-sea biogeography; Dispersal; Genetic diversity; Hydrothermal vents; Marine biogeography; Mid-Atlantic Ridge; Rimicaris exoculata; Spatio-temporal distribution. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00033/14394/12350.pdf |
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Cuvelier, Daphne; Beesau, Julie; Ivanenko, Viatcheslav; Zeppilli, Daniela; Sarradin, Pierre-marie; Sarrazin, Jozee. |
In 2006, paired wood and slate panels, each equipped with a temperature probe, were deployed on three different localities on and around the Eiffel Tower edifice (Lucky Strike vent field, Mid-Atlantic Ridge) within close proximity of visible hydrothermal activity. Recovery of these panels took place in 2008. For this two-year deployment period, the composition of colonising organisms (both macro-and meiofauna) was assessed, along with image analyses of the deployment sites in 2006 and 2008. Very few significant differences in colonisation between organic (wood) and inorganic (slate) panels were revealed. Rather, the locality of deployment and the local environmental conditions and hydrothermal activity were found to influence taxonomic composition.... |
Tipo: Text |
Palavras-chave: Colonisation; Organic and inorganic substrata; Mid-Atlantic Ridge; Hydrothermal; Recruitment; Diversity; Temperature. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00180/29090/27505.pdf |
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Registros recuperados: 62 | |
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