|
|
|
Registros recuperados: 61 | |
|
| |
|
| |
|
|
Josso, P.; Pelleter, Ewan; Pourret, O.; Fouquet, Yves; Etoubleau, Joel; Cheron, Sandrine; Bollinger, C.. |
Ferromanganese (Fe-Mn) deposits constitute a ubiquitous mineral type in oceanic settings, with metal (Cu, Ni, Zn, Co, Pt) and rare earth elements (REE) enrichments of potential economic interest. Routine analysis of trace elements by ICP-MS has advanced our understanding of the impact of hydrogenetic, diagenetic and hydrothermal processes on the mobility and interaction of high field strength elements (HFSE: Zr, Ti) and REE and yttrium (REY) with Fe-Mn oxyhydroxides. Recent discoveries in the French exclusive economic zone (EEZ) of Wallis and Futuna (southwest Pacific Ocean) have brought new insight to the formation of low temperature (LT) hydrothermal Mn deposits and lead us to reconsider the classification and discrimination diagrams for of Fe-Mn... |
Tipo: Text |
Palavras-chave: Ferromanganese mineralization; Hydrogenetic crusts; Nodules; Hydrothermal deposits; Rare earth elements; High field strength elements; Classification. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00350/46156/45854.pdf |
| |
|
|
Sarrazin, Jozee; Sarradin, Pierre-marie; Buffier, Erick; Christophe, Alain; Clodic, Guillaume; Desbruyeres, Damien; Fouquet, Yves; Gouillou, Michel; Jannez, Michel; Le Fur, Yann; Le Rest, Jacques; Lecornu, Fabrice; Lefort, Olivier; Lux, Stephanie; Millet, Brigitte; Guillemet, Pascal. |
The Momareto cruise was held from August 6 to September 6, 2006 on the new French oceanographic vessel Pourquoi pas? The ROV Victor 6000 visited three vent fields, ranging from 850m to 2300m, on the Mid-Atlantic Ridge. The scientific objective of the cruise was to study the spatial and temporal dynamics of hydrothermal communities colonizing these active vent sites. Aside scientific and technological objectives, one of the major goals of this cruise was to share the excitement of our science with the public. For this, the results of the project were shared through different media. The most challenging and exciting communication event remains the real-time transmission of images acquired by the ROV Victor at 1700m depth to a 250 person audience on land. |
Tipo: Text |
Palavras-chave: Deep-sea; Ecosystems; Outreach; Real-time. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3599.pdf |
| |
|
|
Szitkar, Florent; Dyment, Jerome; Fouquet, Yves; Choi, Yujin; Honsho, Chie. |
The analysis of high-resolution vector magnetic data acquired by deep-sea submersibles (DSSs) requires the development of specific approaches adapted to their uneven tracks. We present a method that takes advantage of (1) the varying altitude of the DSS above the seafloor and (2) high-resolution multibeam bathymetric data acquired separately, at higher altitude, by an Autonomous Underwater Vehicle, to estimate the absolute magnetization intensity and the magnetic polarity of the shallow subseafloor along the DSS path. We apply this method to data collected by DSS Nautile on a small active basalt-hosted hydrothermal site. The site is associated with a lack of magnetization, in agreement with previous findings at the same kind of sites: the contrast between... |
Tipo: Text |
|
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00252/36300/34829.pdf |
| |
|
| |
|
|
Auzende, Jean-marie; Ballu, Valerie; Batiza, R; Bideau, Daniel; Cormier, Mh; Fouquet, Yves; Geistdoerfer, Patrick; Lagabrielle, Yves; Sinton, J; Spadea, P. |
The submersible-study of four segments of the East Pacific Rise between 17 degrees and 18 degrees 40'S, where the spreading rate is greater than 150 mm/a, allows us to confirm the variability of the accretion processes. The segment between 17 degrees and 17 degrees 30'S shows an intense present-day magmatic activity. The one between 18 degrees 10' and 18 degrees 22'S shows a mainly tectonic activity. The segment between 18 degrees 22' and 18 degrees 37'S is an intermediate stage with an axial graben in which fresh lavas were emplaced by an extremely young eruption. On all the segments the hydrothermal activity exists ranging from shimmering water up to black smokers, It is associated with different stages of animal colonization. |
Tipo: Text |
Palavras-chave: Océan Pacifique; Dorsale ultra-rapide; Magmatisme; Tectonique; Hydrothermalisme.; PACIFIC OCEAN; ULTRA-FAST SPREADING RIDGE; MAGMATISM; TECTONICS; HYDROTHERMALISM. |
Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00183/29458/27840.pdf |
| |
|
|
Etoubleau, Joel; Bohn, Marcel; Fouquet, Yves; Cambon, Pierre; Le Suave, Raymond. |
A range of X-ray analytical techniques contributes particularly well to the mineralogical and geochemical characterisations of cobalt-rich iron and manganese oxides crusts. X-ray diffraction is used to identify the weak crystallinity of the material. Bulk geochemical characterisation of the crusts is done by X-ray fluorescence for the precise determination of ca. thirty major and trace elements. Fine scale analysis is carried out by electron microprobe to quantitatively map the distribution of elements in oxide phases within the crusts. Microprobe work is essential to obtain the chemical composition of the embedded metallic micro-meteorites. |
Tipo: Text |
|
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00000/10415/9517.pdf |
| |
|
|
Roussel, Erwan; Sauvadet, Anne-laure; Chaduteau, Carine; Fouquet, Yves; Charlou, Jean-luc; Prieur, Daniel; Cambon, Marie-anne. |
P>The distribution of the archaeal communities in deep subseafloor sediments [0-36 m below the seafloor (mbsf)] from the New Caledonia and Fairway Basins was investigated using DNA- and RNA-derived 16S rRNA clone libraries, functional genes and denaturing gradient gel electrophoresis (DGGE). A new method, Co-Migration DGGE (CM-DGGE), was developed to access selectively the active archaeal diversity. Prokaryotic cell abundances at the open-ocean sites were on average similar to 3.5 times lower than at a site under terrestrial influence. The sediment surface archaeal community (0-1.5 mbsf) was characterized by active Marine Group 1 (MG-1) Archaea that co-occurred with ammonia monooxygenase gene (amoA) sequences affiliated to a group of uncultured... |
Tipo: Text |
Palavras-chave: Marine subsurface sediments; Sea floor biosphere; Gradient gel electrophoresis; Microbial communities; Molecular diversity; Anaerobic oxidation; Sequence alignment; Phylogenetic trees; Extracellular DNA; Methane hydrate. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6801.pdf |
| |
|
|
Pierre, Catherine; Fouquet, Yves. |
Submersible investigations with the ROV Victor 6000 of some pockmark structures on the seafloor of the Congo deep-sea fan have shown that they are active venting sites of methane-rich fluids, associated with abundant fauna and carbonate crusts. Moreover, methane hydrates have been observed both outcropping and deep in the sediments in the centre of the "Regab" giant pockmark. Authigenic carbonates, mostly calcite sometimes mixed with aragonite, are cementing the sedimentary matrix components and fauna; diatoms are abundant but only as moulds, indicating that biogenic silica dissolution occurred in situ synchronous with carbonate precipitation. The occurrence of diagenetic barite and pyrite in some carbonate crusts demonstrates that they can be formed... |
Tipo: Text |
Palavras-chave: Oxygen isotopes; Carbon isotopes; Congo deep sea fan; Gas hydrate; Methane seep; Authigenic carbonate. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2608.pdf |
| |
|
|
Colaco, Ana; Bustamante, Paco; Fouquet, Yves; Sarradin, Pierre-marie; Serrao Santos, R. |
In this work, mercury (Hg), copper (Cu) and zinc (Zn) concentrations and tissue distribution are determined in seven benthic invertebrates species (the key species) from the Mid Atlantic Ridge (MAR) hydrothermal vent fields. The samples were collected from three hydrothermal vent fields - Menez Gwen, 840 m;, Lucky Strike, 1700 m and Rainbow, 2300 m - near the Azores Triple Junction. These fields are characterized by different depths, geological context and chemical composition of the hydrothermal fluid, particularly the metal content, which is reflected by the metal concentrations in the organisms. Indeed, our results show that organisms from Menez Gwen presented the highest Hg concentrations, while those from Lucky Strike and Rainbow were richer in Cu and... |
Tipo: Text |
Palavras-chave: Mid Atlantic Ridge; Trophic relations; Trophic transfer; Biomagnification; Vent ecosystems; Heavy metals. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2305.pdf |
| |
|
|
Bougault, Henri; Appriou, P; Birolleau, A; Charlou, Jean-luc; Crane, K; Etoubleau, Joel; Fouquet, Yves; Gente, P; Harmegnies, Francois; Landure, Jean-yves; Le Noac'H, A; Pelle, Henri; Sichler, Bertrand; Voisset, Michel; Watremez, Pierre; Vaslet, N; Jean Baptiste, P. |
Tipo: Text |
|
Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/00070/18104/15652.pdf |
| |
|
|
Bougault, Henri; Appriou, P; Bienvenu, P; Cambon, Pierre; Charlou, Jean-luc; Collette, B; Donval, Jean-pierre; Dosso, Laure; Floch, G; Fouquet, Yves. |
Tipo: Text |
|
Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/00070/18105/15653.pdf |
| |
|
| |
|
|
Gueguen, Bleuenn; Rouxel, Olivier; Rouget, Marie-laure; Bollinger, Claire; Ponzevera, Emmanuel; Germain, Yoan; Fouquet, Yves. |
Ferromanganese (Fe-Mn) crusts are potential archive of the Ni isotope composition of seawater through time. In this study we aim at (1) understanding Ni isotope fractionation mechanisms and metal enrichment processes in Fe-Mn deposits, (2) addressing global vs. local control of Ni isotope composition of these deposits. Two Fe-Mn crusts from the North Pacific Ocean (Apuupuu Seamount, Hawaii) and two Fe-Mn crusts from the South Pacific Ocean (near Rurutu Island, Austral archipelago of French Polynesia) were characterized for their elemental geochemistry and Ni isotope composition. Geochemical analyses were performed at millimeter intervals in order to provide time-resolved record of Ni isotopes. Chronology and growth rates were determined using cosmogenic... |
Tipo: Text |
Palavras-chave: Ferromanganese crusts; Nickel isotopes; Paleoceanography; Pacific Ocean; Biogeochemical cycling. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00341/45255/44696.pdf |
| |
|
|
Roussel, Erwan; Konn, Cecile; Charlou, Jean-luc; Donval, Jean-pierre; Fouquet, Yves; Querellou, Joel; Prieur, Daniel; Cambon-bonavita, Marie-anne. |
The distribution of Archaea and methanogenic, methanotrophic and sulfate-reducing communities in three Atlantic ultramafic-hosted hydrothermal systems (Rainbow, Ashadze, Lost City) was compared using 16S rRNA gene and functional gene (mcrA, pmoA and dsrA) clone libraries. The overall archaeal community was diverse and heterogeneously distributed between the hydrothermal sites and the types of samples analyzed (seawater, hydrothermal fluid, chimney and sediment). The Lost City hydrothermal field, characterized by high alkaline warm fluids (pH>11; T<95 °C), harbored a singular archaeal diversity mostly composed of unaffiliated Methanosarcinales. The archaeal communities associated with the recently discovered Ashadze 1 site, one of the deepest active... |
Tipo: Text |
Palavras-chave: Archaea; Hydrothermal vent; Mid-Atlantic Ridge; 16S rRNA gene; Sediment; Ultramafic. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00067/17836/15573.pdf |
| |
|
| |
|
|
Gaill, Françoise; Ballu, V.; Cannat, M.; Crawford, W.; Dyment, J.; Escartin, J.; Fouquet, Yves; Goslin, J.; Reverdin, G.; Sarradin, Pierre-marie; Tarits, P.; Andreani, M.; Bonnivard, E.; Bucas, Karenn; Burgaud, G.; Cambon-bonavita, Marie-anne; Cueff, Valerie; Durand, C.; Gros, O.; Hamel, G.; Henriques, M.; Hois, E.; Ildefonse, B.; Konn, Cecile; Le Bris, Nadine; Le Guyader, H.; Ravaux, J.; Shilito, B.; Toullec, J.y.; Zbinden, M.. |
Tipo: Text |
|
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/00385/49650/50163.pdf |
| |
|
|
Dyment, J.; Bissessur, D.; Bucas, Karenn; Cueff-gauchard, Valerie; Durand, Lucile; Fouquet, Yves; Gaill, F.; Gente, P.; Hoise, E.; Ildefonse, B.; Konn, Cecile; Lartaud, F.; Le Bris, Nadine; Musset, G.; Nunes, A.; Renard, J.; Riou, V.; Tasiemski, A.; Thibaud, R.; Torres, P.; Yatheesh, V.; Vodjdani, I.; Zbinden, M.. |
Tipo: Text |
|
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00385/49651/50164.pdf |
| |
|
|
Sarradin, Pierre-marie; Lannuzel, D; Waeles, M; Crassous, Philippe; Le Bris, Nadine; Caprais, Jean-claude; Fouquet, Yves; Fabri, Marie-claire; Riso, R. |
The distribution of Fe, Cu, Zn, Pb, Cd between the dissolved (<2 mu m) and the particulate (>2 mu m) fractions was measured after in-situ filtration in two hydrothermal habitats. The total metal concentration ranges exhibit a clear enrichment compared with the seawater concentration, accounting for the hydrothermal input for all the metals considered. Iron is the predominant metal (5-50 mu M) followed by Zn and Cu. Cd and Pb are present at the nM level. At the scale studied, the behavior of temperature, pH and dissolved iron is semi-conservative whereas the other dissolved and particulate metals are characterized by non-conservative patterns. The metal enrichment of the >2 mu m fraction results from the settlement and accumulation of particulate... |
Tipo: Text |
Palavras-chave: Hydrothermal fauna; Habitats; Particulate; Dissolved; Metals. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3830.pdf |
| |
Registros recuperados: 61 | |
|
|
|