Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 11
Primeira ... 1 ... Última
Imagem não selecionada

Imprime registro no formato completo
Comparative geochemistry of four ferromanganese crusts from the Pacific Ocean and significance for the use of Ni isotopes as paleoceanographic tracers ArchiMer
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
Imagem não selecionada

Imprime registro no formato completo
Determination of rare earth elements and other trace elements (Y, Mn, Co, Cr) in seawater using Tm addition and Mg(OH)(2) co-precipitation ArchiMer
Freslon, Nicolas; Bayon, Germain; Birot, Dominique; Bollinger, Claire; Barrat, Jean-alix.
This paper reports on a novel procedure for determining trace element abundances (REE and Y, Cr, Mn, Co) in seawater by inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The procedure uses a combination of pre-concentration using co-precipitation onto magnesium hydroxides and addition of thulium spike. The validity of the method was assessed onto 25 ml volumes of certified reference materials (NASS- and CASS-4) and in house seawater standard. Procedural blanks were determined by applying the same procedure to aliquots of seawater previously depleted in trace elements by successive Mg(OH)(2) co-precipitations, yielding estimated contributions to the studied samples better than 1.1% for all elements, with the exception of Cr (<3.3%)...
Tipo: Text Palavras-chave: Trace elements; Rare earth elements (REE); Seawater; Mg(OH)(2) co-precipitation; ICP-MS; Thulium.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00041/15220/15855.pdf
Imagem não selecionada

Imprime registro no formato completo
Determination of Rare Earth Elements, Sc, Y, Zr, Ba, Hf and Th in Geological Samples by ICP-MS after Tm Addition and Alkaline Fusion ArchiMer
Bayon, Germain; Barrat, Jean Alix; Etoubleau, Joel; Benoit, Mathieu; Bollinger, Claire; Revillon, Sidonie.
We present a revised method for the determination of concentrations of rare earth (REE) and other trace elements (Y, Sc, Zr, Ba, Hf, Th) in geological samples. Our analytical procedure involves sample digestion using alkaline fusion (NaOH-Na2O2) after addition of a Tm spike, co-precipitation on iron hydroxides, and measurement by sector field-inductively coupled plasma-mass spectrometry (SF-ICP-MS). The procedure was tested successfully for various rock types (i.e., basalt, ultramafic rock, sediment, soil, granite), including rocks with low trace element abundances (sub ng g(-1)). Results obtained for a series of nine geological reference materials (BIR-1, BCR-2, UB-N, JP-1, AC-E, MA-N, MAG-1, GSMS-2, GSS-4) are in reasonable agreement with published...
Tipo: Text Palavras-chave: Digestion des Echantillons; Spike de Tm; ICP MS; MatEriaux de rEfErence; Echantillons gEologiques; ElEments du groupe des Terres Rares; Sample digestion; Tm spike; ICP MS; Reference materials; Geological samples; Rare earth elements.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6449.pdf
Imagem não selecionada

Imprime registro no formato completo
Evidence and age estimation of mass wasting at the distal lobe of the Congo deep-sea fan ArchiMer
Croguennec, Claire; Ruffine, Livio; Dennielou, Bernard; Baudin, Francois; Caprais, Jean-claude; Guyader, Vivien; Bayon, Germain; Brandily, Christophe; Le Bruchec, Julie; Bollinger, Claire; Germain, Yoan; Droz, Laurence; Babonneau, Nathalie; Rabouille, Christophe.
On continental margins, sulfate reduction occurs within the sedimentary column. It is coupled with the degradation of organic matter and the anaerobic oxidation of methane. These processes may be significantly disturbed by sedimentary events, leading to transient state profiles for the involved chemical species. Yet, little is known about the impact of turbidity currents and mass wasting on the migration of chemical species and the redox reactions in which they are involved. Due to its connection to the River, the Congo deep-sea fan continuously receives huge amount of organic matter-rich sediments primarily transported by turbidity currents, which impact on the development of the associated ecosystems (Rabouille et al., 2016). Thus, it is well suited to...
Tipo: Text
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00363/47410/47403.pdf
Imagem não selecionada

Imprime registro no formato completo
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
Imagem não selecionada

Imprime registro no formato completo
Microbial colonization of basaltic glasses in hydrothermal organic-rich sediments at Guaymas Basin ArchiMer
Callac, Nolwenn; Rommevaux-jestin, Celine; Rouxel, Olivier; Lesongeur, Francoise; Liorzou, Celine; Bollinger, Claire; Ferrant, Anthony; Godfroy, Anne.
Oceanic basalts host diverse microbial communities with various metabolisms involved in C, N, S, and Fe biogeochemical cycles which may contribute to mineral and glass alteration processes at, and below the seafloor. In order to study the microbial colonization on basaltic glasses and their potential biotic/abiotic weathering products, two colonization modules called AISICS ("Autonomous in situ Instrumented Colonization System") were deployed in hydrothermal deep-sea sediments at the Guaymas Basin for 8 days and 22 days. Each AISICS module contained 18 colonizers (including sterile controls) filled with basaltic glasses of contrasting composition. Chemical analyses of ambient fluids sampled through the colonizers showed a greater contribution of...
Tipo: Text Palavras-chave: Colonization module; Basalt alteration; Guaymas basin; Organic-rich sediment; Hydrothermal systems.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00181/29261/27642.pdf
Imagem não selecionada

Imprime registro no formato completo
Multi-Element Determination of Trace Elements in Natural Water Reference Materials by ICP-SFMS after Tm Addition and Iron Co-precipitation ArchiMer
Bayon, Germain; Birot, Dominique; Bollinger, Claire; Barrat, Jean Alix.
We report on an improved method for determining trace element abundances in seawater and other natural waters. The analytical procedure involves co-precipitation on iron hydroxides after addition of a Tm spike, and measurement by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The validity of the method was assessed through a series of co-precipitation experiments, using ultra-diluted solutions of a certified rock reference material (BIR-1). Results obtained for four natural water reference materials (NASS-5, CASS-4, SLEW-3, SLRS-4) are in agreement with published working values for rare earth elements, yttrium, vanadium and, when available, for hafnium, zirconium, thorium and scandium. A set of proposed values with uncertainties...
Tipo: Text Palavras-chave: Seawater; Reference material; ICP-MS; Trace elements; Rare earth elements; Eau de mer; Materiau de reference; ICP-MS; Elements traces; Terres Rares.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00031/14189/18000.pdf
Imagem não selecionada

Imprime registro no formato completo
Ni-Cu-Co-rich hydrothermal manganese mineralization in the Wallis and Futuna back-arc environment (SW Pacific) ArchiMer
Pelleter, Ewan; Fouquet, Yves; Etoubleau, Joel; Cheron, Sandrine; Labanieh, Shasa; Josso, Pierre; Bollinger, Claire; Langlade, Jessica.
The Wallis and Futuna back-arc system is a complex area composed of at least two active oceanic spreading centers (Futuna and Alofi spreading centers) and young volcanic zones characterized by diffuse magmatism locally affected by the Samoan hotspot. This geological setting is favorable to the establishment of hydrothermal systems either high-temperature (HT) hydrothermal venting or low-temperature (LT) diffuse flow. During the 2010 Futuna cruise aboard R/V L'Atalante, three remarkable inactive LT Fe-Si-Mn deposits have been discovered (i.e. Utu Uli, Anakele and Utu Sega). Some of the Mn-rich precipitates exhibit the highest base metals concentrations so far recorded in ferromanganese rocks including the well-documented hydrogenetic crusts and polymetallic...
Tipo: Text Palavras-chave: Hydrothermal; Diffuse flow; Manganese oxyhydroxides; Metal-rich; Seafloor; Wallis and Futuna Island; South-West Pacific.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00350/46164/45862.pdf
Imagem não selecionada

Imprime registro no formato completo
Pore water geochemistry at two seismogenic areas in the Sea of Marmara ArchiMer
Ruffine, Livio; Germain, Yoan; Polonia, Alina; De Prunele, Alexis; Croguennec, Claire; Donval, Jean-pierre; Pitel-roudaut, Mathilde; Ponzevera, Emmanuel; Caprais, Jean-claude; Brandily, Christophe; Grall, Celine; Bollinger, Claire; Geli, Louis; Gasperini, Luca.
Within the Sea of Marmara, the highly active North Anatolian Fault (NAF) is responsible for major earthquakes (Mw>=7), and acts as a pathway for fluid migration from deep sources to the seafloor. This work reports on pore water geochemistry from three sediment cores collected in the Gulfs of Izmit and Gemlik, along the Northern and the Middle strands of the NAF, respectively. The resulting data set shows that anaerobic oxidation of methane (AOM) is the major process responsible for sulfate depletion in the shallow sediment. In the Gulf of Gemlik, depth concentration profiles of both sulfate and alkalinity exhibit a kink-type profile. The Sulfate Methane Transition Zone (SMTZ) is located at moderate depth in the area. In the Gulf of Izmit, the low...
Tipo: Text Palavras-chave: Anaerobic oxidation of methane; North Anatolian Fault; Pore water geochemistry; Sea of Marmara; Seismic activity.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00272/38339/36570.pdf
Imagem não selecionada

Imprime registro no formato completo
Rare earth elements and neodymium isotopes in sedimentary organic matter ArchiMer
Freslon, Nicolas; Bayon, Germain; Toucanne, Samuel; Bermell, Sylvain; Bollinger, Claire; Chéron, Sandrine; Etoubleau, Joel; Germain, Yoan; Khripounoff, Alexis; Ponzevera, Emmanuel; Rouget, Marie Laure.
We report rare earth element (REE) and neodymium (Nd) isotope data for the organic fraction of sediments collected from various depositional environments, i.e. rivers (n=25), estuaries (n=18), open-ocean settings (n=15), and cold seeps (n=12). Sedimentary Organic Matter (SOM) was extracted using a mixed hydrogen peroxide/nitric acid solution (20%-H2O2 – 0.02M-HNO3), after removal of carbonate and oxy-hydroxide phases with dilute hydrochloric acid (0.25M-HCl). A series of experimental tests indicate that extraction of sedimentary organic compounds using H202 may be complicated occasionally by partial dissolution of sulphide minerals and residual carbonates. However, this contamination is expected to be minor for REE because measured concentrations in H2O2...
Tipo: Text Palavras-chave: Organic matter; Rare earth elements; REE; Neodymium isotopes; ΕNd; Sediment; Boundary Exchange; Paleoceanography.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00191/30250/28682.pdf
Imagem não selecionada

Imprime registro no formato completo
Trace element behaviour at cold seeps and the potential export of dissolved iron to the ocean ArchiMer
Lemaitre, Nolwenn; Bayon, Germain; Ondreas, Helene; Caprais, Jean-claude; Freslon, Nicolas; Bollinger, Claire; Rouget, Marie-laure; De Prunele, Alexis; Ruffine, Livio; Olu-le Roy, Karine; Sarthou, Geraldine.
Seawater samples were collected by submersible above methane seeps in the Gulf of Guinea (Regab and Baboon pockmarks) in order to investigate the behaviour of iron (Fe), manganese (Mn) and rare earth elements (REE) during fluid seepage. Our aim was to determine whether cold seeps may represent potential sources of dissolved chemical species to the ocean. Dissolved (<0.45 μm filtered samples) and total dissolvable (unfiltered samples) concentrations were determined over ∼50 m long vertical transects above the seafloor and at various discrete locations within the pockmarks. We show that substantial amounts of Fe and Mn are released into seawater during seepage of methane-rich fluids. Mn is exported almost quantitatively in the dissolved form (more than...
Tipo: Text Palavras-chave: Iron; Rare earth elements; Cold seeps; Seawater; Organic ligands; Iron-sulfide nanoparticles.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00211/32190/30704.pdf
Registros recuperados: 11
Primeira ... 1 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional