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A comparative Raman spectroscopic study of natural gas hydrates collected at different geological sites ArchiMer
Chazallon, B; Focsa, C; Charlou, Jean-luc; Bourry, Christophe; Donval, Jean-pierre.
Intact natural gas hydrates recovered on the West Aftican margin in the South Atlantic Ocean (ZaiAngo and Neris IIrojects) and from the Norwegian Sea (Hakon Mosby Mud Volcano) are investigated by micro-Raman spectroscopy at ambient pressure and low temperature. The gas hydrates collected at different geological sites contain a high methane concentration relative to other minor components that are slightly dispersed in the samples. They crystallize in a type I cubic lattice structure as also confirmed by our preliminary synchrotron diffraction results obtained on the ZaiAngo specimen. However, detailed analysis of selected microscopic areas reveals a variation in the gas distribution among the different specimens. Trace amounts of CO2 and H2S can be...
Tipo: Text Palavras-chave: Micro Raman spectroscopy; H2S hydrate; CH4 hydrate; Natural clathrate hydrates.
Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-4303.pdf
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A detailed study of the Lucky-Strike hydrothermal site and discovery of a new hydrothermal site: « Menez-Gwen ». Preliminary results of DIVA 1 cruise (5-29 May, 1994) ArchiMer
Fouquet, Yves; Charlou, Jean-luc; Donval, Jean-pierre; Radford-knoery, Joel; Pelle, P; Ondreas, Helene; Lourenco, N; Segonzac, Michel; Tivey, Mk.
Tipo: Text
Ano: 1994 URL: http://archimer.ifremer.fr/doc/00070/18134/15682.pdf
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Analysis of hydrogen and methane in seawater by “Headspace” method: Determination at trace level with an automatic headspace sampler ArchiMer
Donval, Jean-pierre; Guyader, Vivien.
“Headspace” technique is one of the methods for the onboard measurement of hydrogen (H2) and methane (CH4) in deep seawater. Based on the principle of an automatic headspace commercial sampler, a specific device has been developed to automatically inject gas samples from 300 ml syringes (gas phase in equilibrium with seawater). As valves, micro pump, oven and detector are independent, a gas chromatograph is not necessary allowing a reduction of the weight and dimensions of the analytical system. The different steps from seawater sampling to gas injection are described. Accuracy of the method is checked by a comparison with the “purge and trap” technique. The detection limit is estimated to 0.3 nM for hydrogen and 0.1 nM for methane which is close to the...
Tipo: Text Palavras-chave: Gas; Seawater; Headspace method.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00354/46523/46287.pdf
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Analysis of light hydrocarbons in marine sediments by headspace technique: Optimization using design of experiments ArchiMer
Donval, Jean-pierre; Charlou, Jean-luc; Lucas, L..
Headspace technique is a common method to analyze light hydrocarbons in deep marine sediments. The use of an automatic headspace sampler instead of a manual injection is the guarantee for a better repeatability and furthermore it is less time consuming. But to increase the sensitivity and therefore, to achieve a better detection limit, it is necessary to optimize the automatic headspace sampler parameters. The theory of design of experiments was applied here by studying them. As a response, methane, which is an important gas in marine sediments, was chosen for its short analysis time. Regarding the parameters for automatic headspace sampler, eight variables were selected and then, a screening of them was carried out with a fractional factorial design to...
Tipo: Text Palavras-chave: Design of experiments; Headspace technique; Gas; Sediments.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-6235.pdf
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Caminicella sporogenes gen. nov., sp nov., a novel thermophilic spore-forming bacterium isolated from an East-Pacific Rise hydrothermal vent ArchiMer
Alain, Karine; Pignet, Patricia; Zbinden, M; Quillevere, M; Duchiron, F; Donval, Jean-pierre; Lesongeur, Francoise; Raguenes, Gerard; Crassous, Philippe; Querellou, Joel; Cambon-bonavita, Marie-anne.
A novel thermophilic, anaerobic, strictly chemoorganoheterotrophic bacterium, designated as AM1114(T), was isolated from a deep-sea hydrothermal vent sample from the East-Pacific Rise (EPR 13degrees N). The cells were long (3-10 mum) rods, motile with peritrichous flagella, and exhibited a Gram-negative cell wall ultrastructure. In the late stationary phase of growth, cells formed an ovoid, refractile, terminal endospore. They grew at 45-65 degreesC inclusive (optimum 55-60 degreesC; doubling time approx. 45 min), at pH 4.5-8.0 inclusive (optimum pH 7.5-8.0) and at sea salt concentrations of 20-60 g l(-1) inclusive (optimum 25-30 g l(-1)). Strain AM1114(T) was an obligately heterotrophic bacterium able to ferment a mixture of 20 amino acids, complex...
Tipo: Text Palavras-chave: Caminicella sporogenes; Clostridiales; Thermophile; Deep sea hydrothermal vent.
Ano: 2002 URL: http://archimer.ifremer.fr/doc/2002/publication-528.pdf
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Campagne RIDELENTE: Structure de la dorsale Atlantique - Hétérogénéité du manteau et hydrothermalisme ArchiMer
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
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Characterisation of dissolved organic compounds in hydrothermal fluids by stir bar sorptive extraction - gas chomatography - mass spectrometry. Case study: the Rainbow field (36 degrees N, Mid-Atlantic Ridge) ArchiMer
Konn, Cecile; Charlou, Jean-luc; Donval, Jean-pierre; Holm, Nils G..
The analysis of the dissolved organic fraction of hydrothermal fluids has been considered a real challenge due to sampling difficulties, complexity of the matrix, numerous interferences and the assumed ppb concentration levels. The present study shows, in a qualitative approach, that Stir Bar Sorptive Extraction (SBSE) followed by Thermal Desorption - Gas Chromatography - Mass Spectrometry (TD-GC-MS) is suitable for extraction of small sample volumes and detection of a wide range of volatile and semivolatile organic compounds dissolved in hydrothermal fluids. In a case study, the technique was successfully applied to fluids from the Rainbow ultramafic-hosted hydrothermal field located at 36 degrees 14'N on the Mid-Atlantic Ridge (MAR). We show that...
Tipo: Text Palavras-chave: Sample preparation; Extraction; Organic compounds; Hydrothermal fluids; Ultramafic rocks.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00114/22514/20196.pdf
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Comparison of microbial communities associated with three Atlantic ultramafic hydrothermal systems ArchiMer
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
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Contrasted hydrothermal activity along the South-East Indian Ridge (130°E-140°E): From crustal to ultramafic circulation ArchiMer
Boulart, Cedric; Briais, Anne; Chavagnac, Valerie; Revillon, Sidonie; Ceuleneer, Georges; Donval, Jean-pierre; Guyader, Vivien; Barrere, Fabienne; Ferreira, Nicolas; Hanan, Barry; Hemond, Christophe; Macleod, Sarah; Maia, Marcia; Maillard, Agnes; Merkuryev, Sergey; Park, Sung-hyun; Ruellan, Etienne; Schohn, Alexandre; Watson, Sally; Yang, Yun-seok.
Using a combined approach of seafloor mapping, MAPR and CTD survey, we report evidence for active hydrothermal venting along the 130°-140°E section of the poorly-known South-East Indian Ridge (SEIR) from the Australia-Antarctic Discordance (AAD) to the George V Fracture Zone (FZ). Along the latter, we report Eh and CH4 anomalies in the water column above a serpentinite massif, which unambiguously testify for ultramafic-related fluid flow. This is the first time that such circulation is observed on an intermediate-spreading ridge. The ridge axis itself is characterized by numerous off-axis volcanoes, suggesting a high magma supply. The water column survey indicates the presence of at least ten distinct hydrothermal plumes along the axis. The CH4:Mn ratios...
Tipo: Text Palavras-chave: Hydrothermal plumes; Mid-ocean ridges; South-East Indian Ridge.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00387/49821/50400.pdf
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Corrigendum to “Multiple gas reservoirs are responsible for the gas emissions along the Marmara fault network” ArchiMer
Ruffine, Livio; Donval, Jean-pierre; Croguennec, Claire; Burnard, Pete; Lu, Hailong; Germain, Yoan; Legoix, Ludovic N.; Bignon, Laurent; Çağatay, M. Namık; Marty, Bernard; Madre, David; Pitel-roudaut, Mathilde; Henry, Pierre; Géli, Louis.
The authors regret a mistake on the value of δ13C of methane for one of the investigated gas samples. This concerns sample MRS-DV3-PE03, taken as end member and for which the correct methane δ13C value is -41.9‰ and not -34‰. The sample was collected at in situ pressure (~100 bars) from a CO2-rich seep, in a liquid state. The mistake likely results from a partial extraction (i.e. done by expansion of the sampler volume to allow vaporization) of the pressurized sample for subsampling. Additional analyses have been carried out from fully vaporized samples. This error has resulted in updating the geochemical diagrams used for the discussion, and revising both the gas origin for sample MRS-DV3-PE03 and the section entitled “Delineation of sources, reservoirs...
Tipo: Text
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00471/58253/61076.pdf
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Deepwater mantle He-3 plumes over the northern Mid-Atlantic Ridge (36 degrees N-40 degrees N) and the Azores Platform - art. no. Q03010 ArchiMer
Jean Baptiste, P; Fourre, E; Dapoigny, A; Charlou, Jean-luc; Donval, Jean-pierre.
As part of a multidisciplinary project aimed at studying mid-ocean ridge processes near the Azores, fifty water column profiles were analyzed for He-3/He-4 ratios in dissolved helium (a well-known hydrothermal tracer) from 36 degrees N to 40 degrees N along the Mid-Atlantic Ridge (MAR) and over the Azores Plateau. As expected, large delta(3) He anomalies could be observed over the Rainbow, Lucky Strike, and Menez Gwen hydrothermal sites. The main finding of the present study is the discovery of a large hydrothermal 3 He plume north of the Acor Fracture Zone (north AFZ site), with a CH4/He-3 ratio indicative of a basaltic-hosted hydrothermal system. Clear He-3 and CH4 anomalies, likely corresponding to unknown venting sites too, were also detected in the...
Tipo: Text Palavras-chave: Hydrothermal processes; Helium 3; Mid ocean ridges.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-3876.pdf
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Distribution and behavior of dissolved hydrogen sulfide in hydrothermal plumes ArchiMer
Radford Knoery, Joel; German, C; Charlou, Jean-luc; Donval, Jean-pierre; Fouquet, Yves.
Through the deep ocean, hydrothermal plumes disperse high concentrations of key chemical tracers including He-3, CH4, Mn, Fe, H2S, etc. This paper focuses on the distribution and behavior of total dissolved sulfide (sulfide hereafter) in hydrothermal plumes to show that its plume concentration decreases to subnanomolar a few kilometers from the vents. We also report on sulfide removal rates determined at in situ conditions; we observe that they are two orders of magnitude greater than for open ocean seawater, consistent with sulfide being detected only in the vicinity of hydrothermal vents. From our observations, we infer that the sole presence of sulfide in hydrothermal plumes locates active venting at the kilometer scale.
Tipo: Text Palavras-chave: Chemical oceanography; Mid ocean ridges; Metals; Helium isotopes; Methane; Tracers; Hydrogen sulphide; Plumes; Hydrothermal activity.
Ano: 2001 URL: https://archimer.ifremer.fr/doc/2001/publication-688.pdf
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Evidence for intense REE scavenging at cold seeps from the Niger Delta margin ArchiMer
Bayon, Germain; Birot, Dominique; Ruffine, Livio; Caprais, Jean-claude; Ponzevera, Emmanuel; Bollinger, C.; Donval, Jean-pierre; Charlou, Jean-luc; Voisset, Michel; Grimaud, S..
For many trace elements, continental margins are the location of intense exchange processes between sediment and seawater, which control their distribution in the water column, but have yet to be fully understood. In this study, we have investigated the impact of fluid seepage at cold seeps on the marine cycle of neodymium. We determined dissolved and total dissolvable (TD) concentrations for REE and well-established tracers of fluid seepage (CH4, TDFe, TDMn), and Nd isotopic compositions in seawater samples collected above cold seeps and a reference site (i.e. away from any fluid venting area) from the Niger Delta margin. We also analyzed cold seep authigenic phases and various core-top sediment fractions (pore water, detrital component, easily leachable...
Tipo: Text Palavras-chave: Rare earth elements; Neodymium isotopes; Seawater; Cold seeps; Fe-Mn oxyhydroxides; Benthic fluxes.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00066/17754/15571.pdf
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Experimental study of gas hydrate formation and destabilisation using a novel high-pressure apparatus ArchiMer
Ruffine, Livio; Donval, Jean-pierre; Charlou, Jean-luc; Cremiere, Antoine; Zehnder, B. H..
A novel variable-volume type high-pressure apparatus has been designed, constructed and used for gas hydrate investigations. The apparatus has an operating temperature ranging from 253 K to 473 K and pressure ranging from 0.1 MPa to 60 MPa. Its central component consists of a viewing windows cell to which several sensors or analytical instruments can be connected. At its present configuration, a Raman spectrometer and a gas chromatograph are connected for the study of the liquid (or solid) and the gas phases respectively. The apparatus was used for the study of two different systems. The first system was composed of carbon dioxide (CO2) and water for which the hydrate formation and dissolution has been investigated by injecting water into liquid CO2. The...
Tipo: Text Palavras-chave: Gas hydrates; Thermogenic; Carbon dioxide; Formation; Destabilisation; Novel apparatus; Raman spectroscopy; Chromatography.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00006/11759/8472.pdf
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Extensive hydrothermal activity revealed by multi-tracer survey in the Wallis and Futuna region (SW Pacific) ArchiMer
Konn, Cecile; Fourre, E.; Jean-baptiste, P.; Donval, Jean-pierre; Guyader, Vivien; Birot, Dominique; Alix, Anne-sophie; Gaillot, Arnaud; Perez, Florian; Dapoigny, A.; Pelleter, Ewan; Resing, J. A.; Charlou, Jean-luc; Fouquet, Yves.
The study area is close to the Wallis and Futuna Islands in the French EEZ. It exists on the western boundary of the fastest tectonic area in the world at the junction of the Lau and North-Fiji basins. At this place, the unstable back-arc accommodates the plate motion in three ways: (i) the north Fiji transform fault, (ii) numerous unstable spreading ridges, and (iii) large areas of recent volcanic activity. This instability creates bountiful opportunity for hydrothermal discharge to occur. Based on geochemical (CH4, TDM, 3He) and geophysical (nephelometry) tracer surveys: (1) no hydrothermal activity could be found on the Futuna Spreading Center (FSC) which sets the western limit of hydrothermal activity; (2) four distinct hydrothermal active areas were...
Tipo: Text
Ano: 2016 URL: http://archimer.ifremer.fr/doc/00347/45848/45505.pdf
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Extensive magmatic and hydrothermal activity in Manus Basin ArchiMer
Auzende, Jean-marie; Ishibashi, J; Beaudouin, Y; Charlou, Jean-luc; Delteil, J; Donval, Jean-pierre; Fouquet, Yves; Gouillou, Jp; Ildefonse, B; Kimura, H; Nishio, Y; Knoery, Joel; Ruollan, E.
In 1995, a joint French‐Japanese cruise (ManusFlux) explored the Manus Spreading Center and some sites of the South Eastern Rift in the Manus Basin off the coast of Papua New Guinea (Figure 1) with the Japanese submersible [Auzende et al., 1996; Gamo et al., 1997]. In the framework of this joint project, called New STARMER, the French and Japanese teams completed the Manaute cruise with the R/V LAtalante and the Ifremer submersible Nautile in April and May 2000. The Manaute cruise explored and sampled volcanic and hydrothermal sites in the eastern part of Manus Basin and on the spreading axis of the Western Ridge (WR). The eastern part of the Manus Basin (Figure 2) was interpreted as a stretched‐back arc basin crust showing alternatively elongated ridges...
Tipo: Text
Ano: 2000 URL: http://archimer.ifremer.fr/doc/00069/18055/15597.pdf
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FLORES diving cruise with Nautile near the Azores - First dives on the Rainbow field: hydrothermal seawater/mantle interaction ArchiMer
Fouquet, Yves; Barriga, F; Charlou, Jean-luc; Elderfield, H; German, C.r; Ondreas, Helene; Parson, L; Radford-knoery, Joel; Relvas, J; Ribeiro, A; Schultz, A; Apprioual, R; Cambon, P; Costa, I; Donval, Jean-pierre; Douville, E; Landure, Jy; Normand, A; Pelle, H; Ponsevera, E.
Tipo: Text
Ano: 1998 URL: http://archimer.ifremer.fr/doc/00070/18133/15681.pdf
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Focused hydrocarbon-migration in shallow sediments of a pockmark cluster in the Niger Delta (Off Nigeria) ArchiMer
De Prunele, Alexis; Ruffine, Livio; Riboulot, Vincent; Peters, Carl A.; Croguennec, Claire; Guyader, Vivien; Pape, Thomas; Bollinger, Claire; Bayon, Germain; Caprais, Jean-claude; Germain, Yoan; Donval, Jean-pierre; Marsset, Tania; Bohrmann, Gerhard; Geli, Louis; Rabiu, Abdulkarim; Lescanne, Marc; Cauquil, Eric; Sultan, Nabil.
The Niger Delta is one of the largest hydrocarbon basin offshore Africa and it is well known for the presence of active pockmarks on the seabed. During the Guineco-MeBo cruise in 2011, long cores were taken from a pockmark cluster in order to investigate the state of its current activity. Gas hydrates, oil and pore-water were sampled for geochemical studies. The resulting dataset combined with seismic data reveal that shallow hydrocarbon migration in the upper sedimentary section was focused exclusively within the pockmarks. There is a clear tendency for gas migration within the hydrate-bearing pockmarks, and oil migration within the carbonate-rich one. This trend is interpreted as a consequence of hydrate dissolution followed by carbonate precipitation...
Tipo: Text Palavras-chave: Anaerobic oxidation of methane; Cluster of pockmarks; Fluid flow; Gas hydrates; Pore-water profiles; Transient state.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00365/47647/47676.pdf
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Free gas and gas hydrates from the Sea of Marmara, Turkey Chemical and structural characterization ArchiMer
Bourry, Christophe; Chazallon, Bertrand; Charlou, Jean-luc; Donval, Jean-pierre; Ruffine, Livio; Henry, Pierre; Geli, Louis; Cagatay, M. Namik; Inan, Sedat; Moreau, Myriam.
Gas hydrates and gas bubbles were collected during the MARNAUT cruise (May-June 2007) in the Sea of Marmara along the North Anatolian Fault system, Turkey. Gas hydrates were sampled in the western part of the Sea of Marmara (on the Western High), and three gas-bubble samples were recovered on the Western High, the Central High (center part of the Sea of Marmara) and in the Cinarcik Basin (eastern part of the Sea of Marmara). Methane is the major component of hydrates (66.1%), but heavier gases such as C-2, C-3, and i-C-4 are also present in relatively high concentration. The methane contained within gas hydrate is clearly thermogenic as evidenced by a low C-1/C-2 + C-3 ratio of 3.3, and carbon and hydrogen isotopic data (delta C-13(CH4) of -44.1 parts per...
Tipo: Text Palavras-chave: Isotopes; Thermogenic gas; Gas bubbles; Gas hydrate; Sea of Marmara.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6844.pdf
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Gaining insight into Clipperton's lagoon hydrology using tritium ArchiMer
Jean-baptiste, Philippe; Fourre, Elise; Charlou, Jean-luc; Donval, Jean-pierre; Correge, Thierry.
Historical descriptions of the Clipperton lagoon appear to converge on the fact that it became isolated from the surrounding ocean around 1858. Since then, because of the high precipitation rate which largely exceeds evaporation in this region of the eastern tropical Pacific, a brackish lens has formed on top of the saline oceanic waters. In 1980, literature data show that the thickness of this water body was reaching 14 m. During the 2005 Etienne's Clipperton expedition, we collected lagoon water on two vertical profiles. Salinity, delta O-18 and tritium analyses were performed on these samples with the objective of gaining further insight into the lagoon hydrology and age of the deep waters. The upper 15 m were characterized by low salinities (5.4 +/-...
Tipo: Text Palavras-chave: Oxygen isotopes; Tritium; Enclosed lagoon hydrology; Clipperton atoll.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6457.pdf
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