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1. No direct effect of F, Cl and P on REE partitioning between carbonate and alkaline silicate melts

Author

Nabyl, Zineb, Gaillard, Fabrice, Tuduri, Johann, and Carlo, Ida Di

Subjects
Immiscibility processes, Carbonatites, Alkaline magma, Halogens, Phosphorous, Rare earth elements, Geophysics. Cosmic physics, QC801-809, Chemistry, QD1-999, Geology, QE1-996.5
Abstract

This study presents new insights into the effects of halogens (F and Cl) and phosphorous (P) on rare earth element (REE) partitioning between carbonatite and alkaline silicate melts. F, Cl and P are elements that are abundant in carbonatites and alkaline magmatic systems and they are considered to play an important role on the REE behaviour. Nonetheless, their effect on REE partitioning between carbonate and alkaline silicate melts has not yet been constrained.Here we present new experimental data on REE partitioning between carbonate and alkaline silicate melts doped in F, Cl and P, in order to (1) test the Nabyl et al. [2020] REE partitioning model in F-, Cl- and P-rich systems, and (2) identify the possible role of F, Cl and P in carbonate melt REE enrichments during alkaline–carbonatite magma differentiation. The experiments were performed at 850–1050 °C and 0.8 GPa using piston-cylinder devices. Starting materials consisted of carbonatite and phonolite compositions ${\pm }$ doped in F, Cl and P. The experimental results show that REE partitioning is similar in F-Cl-P-rich and -poor systems. The silicate melt composition and its molecular structure (i.e. SiO$_{2}$ contents, the alumina saturation index and the alkali/alkaline-earth element ratio), which have already been identified as controlling REE partitioning in F-, Cl- and P-poor systems, still operate in doped systems. No direct effect of the F, Cl or P melt concentrations on REE partitioning has been identified. We also propose an application to natural systems.

Published
2022
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2. Crystallisation sequence of a REE-rich carbonate melt: an experimental approach

Author

Mollé, Valentin, Gaillard, Fabrice, Nabyl, Zineb, Tuduri, Johann, Di Carlo, Ida, and Erdmann, Saskia

Subjects
Natrocarbonatite, Carbonatite, Rare earth elements, Experimentation, Crystallisation, Calcite, Bastnaesite, Geophysics. Cosmic physics, QC801-809, Chemistry, QD1-999, Geology, QE1-996.5
Abstract

Carbonatites host Earth’s main REE deposits, with bastnaesite (LREE)CO$_3$F being the main economic REE-bearing mineral. However, bastnaesite mineralisation processes are debated between hydrothermal or magmatic origin. This study aims to assess if bastnaesite can be magmatic, and to characterise the REE behaviour during carbonatite crystallisation. Crystallisation experiments have been performed from 900 to 600 °C at 1 kbar, on a REE-rich calciocarbonatitic composition. REE-bearing calcite is the dominant crystallising mineral, driving the residual melt towards natrocarbonatitic compositions. Both halogens (i.e., Cl and F) and water decrease the temperature of calcite saturation. REE are slightly incompatible with calcite: for all REE, partition coefficients between carbonate melt and calcite are comprised between 1 and 11, and increase with temperature decrease. Britholite (REE, Ca)$_{5}$((Si,P)O$_{4}$)$_3$(F,OH) crystallises at high temperatures (700–900 °C), while pyrochlore (Ca,Na,REE)$_{2}$Nb$_{2}$O$_{6}$(OH,F) crystallises at low temperatures (600–700 °C), as well as REE-rich apatite (600–650 °C). No bastnaesite is found in crystallisation experiments. We thus performed a bastnaesite saturation experiment at 600 °C. The bastnaesite-saturated melt contains 20 wt% of REE: such magmatic saturation is unlikely to happen in nature. Textural evidences imply a Na, Cl, REE-rich fluid at high temperatures and hydrous conditions. We propose that fluids are the main mineralising agent for bastnaesite at hydrothermal stage ($

Published
2022
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30. The Jbel Saghro Au(–Ag, Cu) and Ag–Hg Metallogenetic Province: Product of a Long-Lived Ediacaran Tectono-Magmatic Evolution in the Moroccan Anti-Atlas

Author

Tuduri, Johann, primary, Chauvet, Alain, additional, Barbanson, Luc, additional, Bourdier, Jean-Louis, additional, Labriki, Mohamed, additional, Ennaciri, Aomar, additional, Badra, Lakhlifi, additional, Dubois, Michel, additional, Ennaciri-Leloix, Christelle, additional, Sizaret, Stanislas, additional, and Maacha, Lhou, additional

Published
2018
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32. Space and time evolution of ore deposits in the eastern Mediterranean region during the last 100 Myrs: a matter of subduction dynamics

Author

Menant, Armel, Jolivet, Laurent, Guillou-Frottier, Laurent, Tuduri, Johann, Loiselet, Christelle, Bertrand, Guillaume, Sternai, Pietro, Gerya, Taras, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Université de Pau et des Pays de l'Adour (UPPA), Department of Earth Sciences [Cambridge, UK], University of Cambridge [UK] (CAM), and Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)

Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU]Sciences of the Universe [physics], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

36. Positionnement de l'innovation en matière de procédés métallurgiques de traitement et de recyclage - cas des terres rares

Author

Guyonnet, Dominique, Tuduri, Johann, Charles, Nicolas, Melleton, Jérémie, Planchon, Mariane, Escalon, Victoire, Rollat, Alain, Dubois, Didier, Fargier, Hélène, Leroux, Romain, Pourret, Olivier, and Grélaud, Françoise

Subjects
[INFO] Computer Science [cs]
Abstract

La complexité des produits à recycler et la tendance vers des minerais à plus faibles teneurs nécessitent le développement de procédés métallurgiques innovants. Pour bien positionner le développement de tels procédés dans le contexte global de l'économie des ressources minérales, il est important de connaître les flux et stocks de matières premières minérales dans l'anthroposphère. C'est l'objectif du projet Aster, soutenu par l'ANR, que d'identifier ces flux et stocks à l'échelle de l'UE-28, pour les cas de certaines terres rares.

Published
2014

37. A fluid inclusion and stable isotopestudy of the world class imiter silver deposit(Morocco)

Author

Hulin , Claudie, Dubois, Michel, Tuduri, Johann, Chauvet, Alain, Boulvais, Philippe, Al., Et, Dubigeon, Isabelle, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Géosciences Montpellier, Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Terre, Temps, Traçage, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract

International audience; The Imiter silver mine is a world-class deposit located in the Easternpart of the Anti-Atlas (Morocco). The deposit is hosted by Cryogenianblack shales and Ediacaran volcanics, and unconformablyoverlain byPaleozoic sedimentary rocks. The paragenetic sequence for the ganguemineral is composedby amacroscopically white quartz (Qz1) associatedwith the deposition of galena and scarce silver mineralsas matrixof hydraulic breccias, followed by a grey quartz (Qz2) associated withthe main silver deposition event and a first generation of scarcedolomite(Dol1). A third episode is characterized by massive pink dolomite precipitation(Dol2) with minor quartz (Qz3) and base metals. Finally, asurficial event affects the mineralisation and is responsible for a secondaryore enrichment.Microthermometry study coupled with Raman analyses reveals thatfluid inclusions are CaCl2-dominated. The general trend is a decreaseof temperature from Qz1 (250°C) to Dol1 (80°C) then Dol 2 (probablybelow 70°C) depositions. Fluid salinity increases from Qz1 (6.3 to 19.0wt % NaCleq) to Dol1 (27.2 % wt NaCleq), and decreases with the precipitationof Dol2 associated with quartz 3 (15 %wt NaCleq). The 18Oisotopic composition of fluids in equilibrium with quartz and dolomitesuggestsamagmatic,metamorphic and/or basinal origin for the fluid atthe origin of Qz1, and that meteoric / surficial basinal brinesmay be atthe origin of Dol2.The proposed model to explain the ore forming processes in Imiter is amixing of Ca-brines, probably providing chloride complexes, with a hotNaCl fluid of lower salinity, leading to the precipitation of silver.Theresults favour the important role of calcic brines, whose origin remainsmatter to debate in such a giant depositand for whom age of emplacementis strongly discussed.

Published
2014

39. Modèle de formation du gisement d'argent d'Imiter (Anti-Atlas oriental, Maroc). Nouveaux apports de l'analyse structurale et minéralogique. Model of formation of the Imiter silver deposit (eastern Anti-Atlas, Morocco). New structural and mineralogical constraints

Author

Tuduri, Johann, Chauvet, Alain, Ennaciri, Aomar, Barbanson, Luc, Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Dynamique de la Lithosphère (LDL), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Société métallurgique d'Imiter (SMI)

Subjects
Maroc, Veines, Contrôle structural, Argent, Anti-Atlas oriental, Transpression, Imiter, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract

Based on a combined geometrical and mineralogical analysis, a three-stage model of formation of the mineralized veins of the giant Imiter silver deposit (Anti-Atlas, Morocco) is herein proposed. A first episode is characterized by the development of quartz, pink dolomite and Ag-rich minerals veins formed during a dextral transpressive event. The second episode is associated with a normal left-lateral motion that re-opens previous structures, filled by pink dolomite gangue. Alteration stages contribute to a local Ag enrichment. Basé sur l'étude de nouvelles données géométriques et minéralogiques, un modèle de formation en trois stades des veines du gisement d'argent d'Imiter (Anti-Atlas oriental, Maroc) est proposé. Le premier stade est caractérisé par le développement des veines les plus riches, à remplissage de quartz puis dolomite rose, dans un contexte transpressif dextre associé à une direction de raccourcissement NW–SE à WNW–ESE. Le second stade, à remplissage de dolomite rose, est associé à un cisaillement senestre normal, contrôlé par une direction de raccourcissement nord–sud, réutilisant certaines des structures du stade 1. Des phénomènes d'altération contribuent à un enrichissement local en Ag.

Published
2006

41. No direct effect of F, Cl and P on REE partitioning between carbonate and alkaline silicate melts.

Author

Nabyl, Zineb, Gaillard, Fabrice, Tuduri, Johann, and Di Carlo, Ida

Subjects
*CARBONATES, *RARE earth metals, *MOLECULAR structure, *SILICATES, *PHONOLITE, *MELTING, *CARBONATITES
Abstract

This study presents new insights into the effects of halogens (F and Cl) and phosphorous (P) on rare earth element (REE) partitioning between carbonatite and alkaline silicate melts. F, Cl and P are elements that are abundant in carbonatites and alkaline magmatic systems and they are considered to play an important role on the REE behaviour. Nonetheless, their effect on REE partitioning between carbonate and alkaline silicate melts has not yet been constrained. Here we present new experimental data on REE partitioning between carbonate and alkaline silicate melts doped in F, Cl and P, in order to (1) test the Nabyl et al. [2020] REE partitioning model in F-, Cl- and P-rich systems, and (2) identify the possible role of F, Cl and P in carbonate melt REE enrichments during alkaline–carbonatitemagma differentiation. The experiments were performed at 850–1050 °C and 0.8 GPa using piston-cylinder devices. Starting materials consisted of carbonatite and phonolite compositions ± doped in F, Cl and P. The experimental results show that REE partitioning is similar in F-Cl-P-rich and -poor systems. The silicate melt composition and its molecular structure (i.e. SiO2 contents, the alumina saturation index and the alkali/alkaline-earth element ratio), which have already been identified as controlling REE partitioning in F-, Cl- and P-poor systems, still operate in doped systems. No direct effect of the F, Cl or P melt concentrations on REE partitioning has been identified. We also propose an application to natural systems. [ABSTRACT FROM AUTHOR]

Published
2021
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43. Crystallisation sequence of a REE-rich carbonate melt: an experimental approach.

Author

Mollé, Valentin, Gaillard, Fabrice, Nabyl, Zineb, Tuduri, Johann, Di Carlo, Ida, and Erdmann, Saskia

Subjects
*CRYSTALLIZATION, *BASTNAESITE, *CARBONATES, *WATER temperature, *RARE earth metals, *LOW temperatures
Abstract

Carbonatites host Earth’s main REE deposits, with bastnaesite (LREE)CO3F being the main economic REE-bearing mineral. However, bastnaesite mineralisation processes are debated between hydrothermal or magmatic origin. This study aims to assess if bastnaesite can be magmatic, and to characterise the REE behaviour during carbonatite crystallisation. Crystallisation experiments have been performed from 900 to 600 °C at 1 kbar, on a REE-rich calciocarbonatitic composition. REEbearing calcite is the dominant crystallising mineral, driving the residual melt towards natrocarbonatitic compositions. Both halogens (i.e., Cl and F) and water decrease the temperature of calcite saturation. REE are slightly incompatible with calcite: for all REE, partition coefficients between carbonate melt and calcite are comprised between 1 and 11, and increase with temperature decrease. Britholite (REE, Ca)5((Si,P)O4)3(F,OH) crystallises at high temperatures (700–900 °C), while pyrochlore (Ca,Na,REE)2Nb2O6(OH,F) crystallises at low temperatures (600–700 °C), as well as REE-rich apatite (600–650 °C). No bastnaesite is found in crystallisation experiments.We thus performed a bastnaesite saturation experiment at 600 °C. The bastnaesite-saturated melt contains 20 wt% of REE: such magmatic saturation is unlikely to happen in nature. Textural evidences imply a Na, Cl, REE-rich fluid at high temperatures and hydrous conditions.We propose that fluids are the main mineralising agent for bastnaesite at hydrothermal stage (<600 °C). [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
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