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Registros recuperados: 19 | |
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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 |
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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 |
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Grenier, Melanie; Garcia-solsona, Ester; Lemaitre, Nolwenn; Trull, Thomas W.; Bouvier, Vincent; Nonnotte, Philippe; Van Beek, Pieter; Souhaut, Marc; Lacan, Francois; Jeandel, Catherine. |
Distributions of dissolved rare earth element (REE) concentrations and neodymium isotopic compositions (expressed as epsilon(Nd)) of seawater over and off the Kerguelen Plateau in the Southern Ocean are presented. The sampling took place during the austral spring bloom in October-November 2011 (KEOPS2 project, GEOTRACES process study) and aimed to further the investigations of the KEOPS1 austral summer study in terms of sources and transport of lithogenic material, and to investigate the impact of local biogeochemical cycles on the REE distributions. The REE signature of the coastal eastern Kerguelen Islands waters was characterized by negative europium anomalies (Eu/Eu*) and negative epsilon(Nd) in filtered samples. By contrast, the unfiltered sample... |
Tipo: Text |
Palavras-chave: Southern Ocean; Kerguelen Islands; Rare earth elements; Fractionation; Anomalies; Lithogenic; Biologic; GEOTRACES. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00616/72764/72274.pdf |
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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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MOTOKI,AKIHISA; SICHEL,SUSANNA E.; VARGAS,THAIS; MELO,DEAN P.; MOTOKI,KENJI F.. |
ABSTRACT This paper presents geochemical behaviour of trace elements of the felsic alkaline rocks of the state of Rio de Janeiro, Brazil, with special attention of fractional crystallization and continental crust assimilation. Fractionation of leucite and K-feldspar increases Rb/K and decreases K2O/(K2O+Na2O). Primitive nepheline syenite magmas have low Zr/TiO2, Sr, and Ba. On the Nb/Y vs. Zr/TiO2 diagram, these rocks are projected on the field of alkaline basalt, basanite, and nephelinite, instead of phonolite. Well-fractionated peralkaline nepheline syenite has high Zr/TiO2 but there are no zircon. The diagrams of silica saturation index (SSI) distinguish the trends originated form fractional crystallization and crustal assimilation. In the field of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nepheline syenite; Alkaline syenite; Trace elements; Rare earth elements; Fractional crystallization; Continental crust assimilation. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000501959 |
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Duarte, Ana Carolina Oliveira; Oliveira, Cynthia de; Ramos, Sílvio Júnio; Castro, Evaristo Mauro de; Siqueira, José Oswaldo; Guilherme, Luiz Roberto Guimarães. |
Rare earth elements, such as lanthanum (La), have been applied to agriculture via fertilizers, aiming to increase the productivity and crop quality, such results observed mainly in China. However, the knowledge about the effect of La on maize growth, as well as for other species, despite the growing interest it is still limited. The aim of this study was to evaluate the effects of La on maize growth, La content, photosynthetic rate and chlorophyll content in maize plants in response to La treatment (0, 25, 50, 100, 150, 300 and 600 μM) in nutrient solution for three weeks. The plants were placed in geminated pots using a split-root technique. One of the pots in the geminated set was filled with a complete nutrient solution without La, while another was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ciências Agrárias crops; Photosynthesis; Rare earth elements; Zea mays. Produção Vegetal. |
Ano: 2018 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/38469 |
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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 |
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Giresse, Pierre; Bayon, Germain; Tallobre, Cédric; Loncke, Lies. |
Contourite sediment accumulations at continental margins are related to strong bottom water circulation, where intense winnowing can result in neoformation of authigenic grains of glauconite at the seafloor. In this study, we investigated whether such glauconite grains could faithfully record ambient bottom-water neodymium (Nd) isotopic compositions, and hence be used as paleoceanographic archives. To this purpose, we measured Nd isotopic compositions (εNd) in a series of glauconitic grains, foraminiferal assemblages, leached Fe-Mn oxyhydroxide phases, and detrital clays separated from a contourite sediment record at the Demerara slope off French Guiana (IG-KSF-11; 2370 m water depth), at a location where the present-day εNd distribution along the water... |
Tipo: Text |
Palavras-chave: Rare earth elements; Neodymium isotopes; Glauconitisation; Demerara; Contourite. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00689/80085/83115.pdf |
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Barrat, Jean-alix; Ferrière, L.. |
Main-group pallasites (MGPs) are meteorites mainly composed of Fe-Ni metal and olivines, the latter being considered as one of the largest sampling of extraterrestrial mantle material available for study on Earth. We analysed the rare earth element (REE) concentrations of olivines from six MGPs to understand better the processes of formation of their parent mantle. All the investigated samples display very low REE abundances, and enrichments in both light REEs and heavy REEs. We interpret the light REE enrichments as a fingerprint of terrestrial contamination. The least contaminated olivines have higher heavy REE enrichments than those inferred for olivines directly crystallised in a magma ocean. Such enrichments in heavy REEs are possible if the mantle of... |
Tipo: Text |
Palavras-chave: Pallasite; Early solar system; Trace elements; Rare earth elements; Differentiation. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00686/79770/82569.pdf |
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Hathorne, Ed C.; Stichel, Torben; Brueck, Bastian; Frank, Martin. |
The concentrations of rare earth elements (REEs) in seawater display systematic variations related to weathering inputs, particle scavenging and water mass histories. Here we investigate the REE concentrations of water column profiles in the Atlantic sector of the Southern Ocean, a key region of the global circulation and primary production. The data reveal a pronounced contrast between the vertical profiles in the Antarctic Circumpolar Current (ACC) and those south of the ACC in the Weddell Gyre (WG). The ACC profiles exhibit the typical increase of REE concentrations with water depth and a change in the shape of the profiles from near linear for the light REEs to more convex for the heavy REEs. In contrast, the WG profiles exhibit high REE concentrations... |
Tipo: Text |
Palavras-chave: Rare earth elements; Atlantic sector of the Southern Ocean; Weddell Gyre; GEOTRACES. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00294/40504/83046.pdf |
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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 |
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Wu, Jiawang; Filippidi, Amalia; Davies, Gareth R.; De Lange, Gert J.. |
Organic-rich sapropel sediments were repeatedly deposited in the eastern Mediterranean Sea (EMS), in response to insolation-driven freshwater forcing. However, the exact freshwater sources and causal associated paleoclimate-related processes remain unresolved. Sapropel S5, formed during the insolation maximum of the last interglacial, is one of the most intensely developed sapropels of the Late-Quaternary. Here, detrital sediments of sapropel S5 obtained from 8 cores, together with 13 EMS surface samples, are analyzed for major elements, rare earth elements, and Sr and Nd isotopes. This permits a basin-wide investigation of the source and distribution of river-borne material to the EMS for sapropel S5, and its comparison to the present-day and the Holocene... |
Tipo: Text |
Palavras-chave: Sapropel S5; Eastern Mediterranean Sea; Provenance; Radiogenic isotopes; Major elements; Rare earth elements. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00435/54623/56024.pdf |
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Chavagnac, Valerie; Ali, Hassan Saleban; Jeandel, Catherine; Leleu, Thomas; Destrigneville, Christine; Castillo, Alain; Cotte, Laura; Waeles, Mathieu; Cathalot, Cecile; Laes, Agathe; Pelleter, Ewan; Nonnotte, Philippe; Sarradin, Pierre-marie; Cannat, Mathilde. |
While hydrothermal vents are now thought to be a major source of dissolved iron to the oceans, they have always been considered to be a sink for the dissolved rare-earth elements (DREEs). However, true dissolved REE observations in hydrothermal plumes are still lacking. Here we report for the first time the DREE concentrations and neodymium isotopic compositions (DεNd) of buoyant hydrothermal fluids at Lucky Strike (Mid-Atlantic Ridge). We find that 27 to 62% of total hydrothermal DREEs are rapidly scavenged by anhydrite precipitation at the onset of buoyant plume formation. After this initial loss, all DREEs behave quasi-conservatively within the buoyant plume. Dissolved phase εNd (DεNd) in the evolving plume are identical to black smoker DεNd of +9.0 and... |
Tipo: Text |
Palavras-chave: Black smokers; Rare earth elements; Neodymium isotopes; Hydrothermal; Sulfate minerals; EMSO-Azores. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00456/56733/58511.pdf |
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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 |
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Charles, Claire; Barrat, Jean-alix; Pelleter, Ewan. |
In order to propose an optimal analytical procedure specific to ferromanganese (Fe-Mn) oxides, we investigated different modes of data acquisition using inductively coupled plasma mass spectrometry (ICP-MS). The results of trace element and Rare Earth Element (REE) determination in eight Fe-Mn nodules and crusts (FeMn-1, GSMC-1, GSMC-2, GSMC-3, GSPN-2, GSPN-3, NOD-A-1 and NOD-P-1) are presented here. The analytical procedure involves chemical dissolution of the Fe-Mn oxides and addition of a thulium (Tm) spike. The correction of measured values from potential isobaric interferences was investigated using both corrections based on mono-elemental solutions, and data acquisition in the high-resolution mode. The obtained results show that the high-resolution... |
Tipo: Text |
Palavras-chave: ICP-MS; Fe-Mn oxides; Trace elements; Rare earth elements; High-resolution; Tm spike. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00692/80377/83498.pdf |
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Registros recuperados: 19 | |
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