Готові списки джерел за темами / Rare earth element geochemistry

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Опубліковано: 10 грудня 2022
Оновлено: 28 січня 2023

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Статті в журналах з теми "Rare earth element geochemistry"

1

Preston, R. M. F. "Rare earth element geochemistry." Earth-Science Reviews 22, no. 3 (November 1985): 242–43. http://dx.doi.org/10.1016/0012-8252(85)90064-9.

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Middlemost, E. A. K. "Rare earth element geochemistry." Chemical Geology 48, no. 1-4 (March 1985): 362–63. http://dx.doi.org/10.1016/0009-2541(85)90062-2.

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3

McLennan, Scott M. "Rare earth element geochemistry and the “tetrad” effect." Geochimica et Cosmochimica Acta 58, no. 9 (May 1994): 2025–33. http://dx.doi.org/10.1016/0016-7037(94)90282-8.

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4

Lawrence, Michael G., Stacy D. Jupiter, and Balz S. Kamber. "Aquatic geochemistry of the rare earth elements and yttrium in the Pioneer River catchment, Australia." Marine and Freshwater Research 57, no. 7 (2006): 725. http://dx.doi.org/10.1071/mf05229.

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The rare earth elements are strong provenance indicators in geological materials, yet the potential for tracing provinciality in surface freshwater samples has not been adequately tested. Rare earth element and yttrium concentrations were measured at 33 locations in the Pioneer River catchment, Mackay, central Queensland, Australia. The rare earth element patterns were compared on the basis of geological, topographical and land-use features in order to investigate the provenancing potential of these elements in a small freshwater system. The rare earth element patterns of streams draining single lithological units with minor land modification show strongly coherent normalised behaviour, with a loss of coherence in agricultural locations. Evidence is reported for an anthropogenic Gd anomaly that may provide a useful hydrological tracer in this region since the introduction of magnetic resonance imaging in 2003. Several samples display a superchondritic Y/Ho mass ratio (up to 44), which is not explainable within the constraints imposed by local geology. Instead, it is suggested that the additional Y is derived from a marine source, specifically marine phosphorites, which are a typical source of fertiliser phosphorus. The data indicate that, under some circumstances, scaled and normalised freshwater rare earth patterns behave conservatively.
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5

Ireland, T. R., J. N. Ávila, M. Lugaro, S. Cristallo, P. Holden, P. Lanc, L. Nittler, C. M. O'D Alexander, F. Gyngard, and S. Amari. "Rare earth element abundances in presolar SiC." Geochimica et Cosmochimica Acta 221 (January 2018): 200–218. http://dx.doi.org/10.1016/j.gca.2017.05.027.

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6

MAKISHIMA, Akio, and Eizo NAKAMURA. "Review in Zirconology. III. Rare-earth element geochemistry of zircon." JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY 89, no. 1 (1994): 1–14. http://dx.doi.org/10.2465/ganko.89.1.

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7

Trueman, Clive N. "Rare Earth Element Geochemistry and Taphonomy of Terrestrial Vertebrate Assemblages." PALAIOS 14, no. 6 (December 1999): 555. http://dx.doi.org/10.2307/3515313.

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8

Kim, K. H., S. G. Lee, J. K. Kim, and D. Y. Yang. "Rare earth element geochemistry in fresh rock-weathered rock-soil." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A318. http://dx.doi.org/10.1016/j.gca.2006.06.642.

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9

Hsu, Weibiao, Yunbin Guan, Henian Wang, Laurie A. Leshin, Rucheng Wang, Wenlan Zhang, Xiaoming Chen, Fusheng Zhang, and Chengyi Lin. "The lherzolitic shergottite Grove Mountains 99027: Rare earth element geochemistry." Meteoritics & Planetary Science 39, no. 5 (May 2004): 701–9. http://dx.doi.org/10.1111/j.1945-5100.2004.tb00113.x.

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10

Bouch, J. E., M. J. Hole, and N. H. Trewin. "Rare earth and high field strength element partitioning behaviour in diagenetically precipitated titanites." Neues Jahrbuch für Mineralogie - Abhandlungen 172, no. 1 (September 10, 1997): 3–21. http://dx.doi.org/10.1127/njma/172/1997/3.

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Більше джерел

Дисертації з теми "Rare earth element geochemistry"

1

Mitra, Arabinda. "Rare earth element systematics of submarine hydrothermal fluids and plumes." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386339.

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2

Lozano, Letellier Alba. "Geochemistry of rare earth elements in acid mine drainage precipitates." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/668458.

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Rare earth elements (REE) are known as the lanthanide series (La-Lu) plus yttrium (Y) and scandium (Sc). REE are essential materials for modern industries and especially for green technologies (wind turbines, batteries, lasers, catalysts, etc.). However, despite their high global demand, their supply is limited such that the EU has cataloged it as critical raw materials. In order to ensure the supply of REE in the future, the search for alternative sources of these elements worldwide has been promoted in recent years. Acid mine drainage (AMD) produced by the Fe-sulphide weathering can effectively leach Fe, Al, SO4, and REE from the host rock. This can lead to high concentrations of these liberated species in the affected waters. Thus, the REE concentrations in AMD can be between two and three orders of magnitude higher than natural waters, as such it can be considered as a complementary source of REE recovery. The increase of pH in AMD by mixing neutral waters results in the precipitation of iron oxy-hydroxysulfate (schwertmannite) from pH 3-3.5, and aluminum (basaluminite) from pH 4-4.5 in the river channels. This process may be accompanied by REE scavenging. Due to its acidity and high metal load, acid mine drainage presents a major environmental problem worldwide, therefore, different treatment systems have been developed to minimize its impact. Disperse Alkaline Substrate (DAS) passive remediation system neutralizes AMD by dissolving calcite, and allowing the sequential precipitation of schwertmannite and basaluminite in separated layers, where REE are preferably retained in the basaluminite-enriched waste. Despite this, there are still no studies describing the adsorption of REE on both basaluminite and schwertmannite in these environments. The REE scavenging mechanism is studied by adsorption on synthetic minerals of basaluminite and schwertmannite as a result of variation to the both the pH and sulfate concentration. A thermodynamic adsorption model is proposed based on experimental results in order to predict and explain the REE mobility in AMD mixtures with neutral waters and in a passive treatment system. Basaluminite and schwertmannite have a nanocrystalline character. Further, schwertmannite has been observed to transform into goethite on weekly timescales, resulting in sulfate release. However, there is a gap of knowledge about basaluminite stability at variable sulfate concentration and pH and its possible transformation to other more crystalline Al-minerals. In this study, basaluminite local order at different pH values and dissolved sulfate concentrations was characterized. Results demonstrate that basaluminite can transform to nanoboehmite in weeks under circumneutral pH. However, the presence of sulfate can inhibit this transformation. Separate adsorption experiments on both basaluminite and schwertmannite were performed with two different concentrations of SO4 while varying the pH (3-7). Results show that the adsorption is strongly dependent on pH, and to a lesser extent on sulfate concentration. Lanthanide and yttrium adsorption is most effective near pH 5 and higher, while that of scandium begins around pH 4. Due to the high concentrations of sulfate in acidic waters, the predominant aqueous REE species are sulfate complexes (MSO4+). Notably, Sc(OH)2+ represents a significant proportion of aqueous Sc. , A surface complexation model is proposed in which predominant aqueous species (Mz+) adsorb on the mineral surface, XOH, following the reaction: The adsorption of the lanthanides and yttrium occurs through the exchange of one and two protons from the basaluminite and schwertmannite surface, respectively, with the aqueous sulfate complexes. The sorbed species form monodentate surface complexes with the aluminum mineral and bidentate with the iron mineral. In the case of Sc, the aqueous species ScSO4+ and Sc(OH)2+ form bidentate surface complexes with both minerals. EXAFS analysis of the YSO4+ complex adsorbed on the basaluminite surface suggests the formation of a monodentate inner sphere complex, in agreement with the proposed thermodynamic model. Once the surface complexation model was validated, it was used to asses and predict the REE mobility in passive remediation systems and acidic water mixing zones with alkaline inputs from the field. The REE are preferentially retained in basaluminite-rich waste during passive remediation due to its sorption capacity between pH 5-6. In contrast, schwertmannite waste contains very little REE because the formation of this mineral occurs at pH lower than 4, which prevents REE adsorption. Further, Sc may be scavenged during schwertmannite precipitation as a result of this low pH The model correctly predicts the absence of REE in schwertmannite precipitates and the enrichment of the heavy and intermediate REE with respect to the light REE in basaluminite precipitates collected in the water mixing zones. However, there is a systematic overestimation of the fractionation of rare earths in basaluminite precipitate. This inaccuracy is mainly due to the fact that the mineral precipitation and adsorption are not synchronous process, while basaluminite precipitates from pH 4, REE adsorption occurs at higher pH values, between 5 and 7, when the water mixture reaches these values and a fraction of the particles have been dispersed.
Las tierras raras (en inglés rare earth elements, REE) son conocidas como el conjunto de la serie de los lantánidos (La-Lu), itrio (Y) y escandio(Sc). Las tierras raras son materiales indispensables para las industrias modernas y en especial para las tecnologías verdes (aerogeneradores, baterías, láseres, catalizadores, etc.). Sin embargo a pesar de su gran demanda mundial, su abastecimiento es limitado, por lo que han sido catalogadas por la UE como materias primas críticas (Critical Raw Materials). Con el objetivo de asegurar el abastecimiento de REE en el futuro, en los últimos años se ha promovido la búsqueda de fuentes alternativas de estos elementos en todo el mundo. El drenaje ácido de mina (en inglés acid mine drainage, AMD) producido por la meteorización de sulfuros de Fe, tiene un alto poder de lixiviación de las rocas, por lo que las aguas afectadas adquieren elevadas concentraciones en disolución de Fe, Al, SO4 y otros metales, como las REE. Así, las concentraciones de REE en AMD son entre dos y tres órdenes de magnitud superiores al resto de las aguas naturales y pueden suponer una fuente complementaria de recuperación de REE. El aumento de pH del AMD por mezcla con aguas neutras da lugar a la precipitación en los cauces de los ríos de oxy-hidroxisulfatos de hierro (schwertmannita), a partir de pH 3-3.5, y de aluminio (basaluminita), a partir de pH 4-4.5; acompañado de la eliminación de las tierras raras. Debido a su acidez y carga metálica, el drenaje ácido de mina presenta un problema medioambiental de primera magnitud, por lo que se han desarrollado diferentes sistemas de tratamiento para minimizar su impacto. El sistema de tratamiento pasivo Disperse Alkaline Substrate (DAS) produce la neutralización de las aguas ácidas por la disolución de la calcita presente en el sistema, permitiendo la precipitación secuencial, de schwertmannita y basaluminita. Las tierras raras quedan retenidas preferentemente en el residuo enriquecido en basaluminita. A pesar de ello, aún no existen estudios que describan la adsorción de tierras raras tanto en basaluminita como schwertmannita en estos ambientes. En esta tesis se estudia el mecanismo de retención de las tierras raras mediante adsorción en minerales sintéticos de basaluminita y schwertmannita, en función del pH y del contenido de sulfato disuelto. Con los resultados experimentales obtenidos, se propone un modelo termodinámico de adsorción para predecir y explicar la movilidad de las tierras raras observada en mezclas de AMD con aguas neutras y en un sistema de tratamiento pasivo. La basaluminita y la schwertmannita presentan un carácter nanocristalino. Es conocido que la schwertmannita se transforma en goethita en semanas, liberando sulfato. Sin embargo, nada se sabe de la basaluminita y su posible transformación a otros minerales de Al más cristalinos. De este modo, la caracterización del orden local de la basaluminita a diferentes valores de pH y sulfato se expone en primer lugar. Dependiendo del pH y el sulfato en disolución, la basaluminita se transforma en diferentes grados a nanoboehmita en semanas, pero tiende a estabilizarse con la presencia de sulfato en solución. Los experimentos de adsorción en basaluminita y schwertmannita con diferentes concentraciones de SO4 realizados para cada mineral y en rangos de 3-7 de pH han demostrado que la adsorción es fuertemente dependiente del pH, y en menor medida del sulfato. La adsorción de los lantánidos y del itrio es efectiva a pH 5, mientras que la del escandio comienza a pH 4. Debido a las altas concentraciones de sulfato en aguas ácidas, las especies acuosas predominantes de las tierras raras son los complejos con sulfato, MSO4+. Además del complejo sulfato, el Sc presenta importantes proporciones de Sc(OH)2+ en solución. En función de la dependencia del pH y de la importancia de la especiación acuosa, se propone un modelo de complejación superficial donde la especie acuosa predominante (Mz+) se adsorbe a la superficie libre el mineral, XOH, cumpliendo la siguiente reacción: La adsorción de los lantánidos y del itrio se produce a través del intercambio de uno o dos protones de la superficie de la basaluminita o de la schwertmannita, respectivamente, con los complejos sulfato acuoso, formando complejos superficiales monodentados con el mineral de aluminio y bidentados con el de hierro. En el caso del Sc, las especies acuosas ScSO4+ y Sc(OH)2+ forman complejos superficiales bidentados con ambos minerales. Complementando el modelo propuesto, el análisis de EXAFS del complejo YSO4+ adsorbido en la superficie basaluminita sugiere la formación de un complejo monodentado de esfera interna, coincidiendo con el modelo termodinámico propuesto. El modelo de complejación superficial, una vez validado, ha permitido evaluar y predecir la movilidad de REE en los sistemas de tratamiento pasivos y en zonas de mezcla de aguas ácidas con aportes alcalinos estudiados en el campo. La preferente retención de las tierras raras en la zona de la basaluminita precipitada en los sistemas de tratamiento pasivo ocurre por adsorción de las mismas a pH entre 5-6. La ausencia de tierras raras en la zona de schwertmannita se debe al bajo pH de su formación, inferior a 4, que impide la adsorción de las mismas. Sin embargo, debido a su menor pH de adsorción, una fracción de Sc puede quedar retenida en la schwertmannita. El modelo también predice correctamente la ausencia de REE en los precipitados de schwertmannita y el enriquecimiento de las tierras raras pesadas e intermedias respecto a las ligeras en los precipitados de basaluminita recogidos en el campo en las zonas de mezcla de aguas. Sin embargo, se ha observado una sistemática sobreestimación del fraccionamiento de las tierras raras en los precipitados de basaluminita. Este hecho se debe principalmente a que la precipitación del mineral no ocurre de forma síncrona con la adsorción, precipitando la basaluminita a partir de pH 4 y adsorbiendo tierras raras a pH más altos, entre 5 y 7, cuando las partículas sólidas han sido parcialmente dispersadas.
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3

Brown, TJ. "Geology & Geochemistry of the Kingman Feldspar, Rare Metals and Wagon Bow Pegmatites." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1280.

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In the Mojave Pegmatite district, located in northwestern AZ, numerous pegmatites intrude syn- to post-collisional Paleoproterozoic granitic rocks. The slightly older Cerbat plutons are associated with the suturing of the Mojave and Yavapai terranes whereas Aquarius granites were emplaced during the Yavapai Orogeny as the sutured terranes docked with North America. A detailed study of 5 pegmatites shows that they are zoned with composite cores and contain REE minerals characteristic of NYF pegmatites. However, they exhibit characteristics atypical for NYF pegmatites including F depletion, white microcline, an absence of columbite and, in the Rare Metals pegmatite, have muscovite and beryl. With the exception of the Kingman pegmatite, they exhibit normal LREE-HREE distributions. The Kingman pegmatite is extremely LREE enriched, HREE depleted and exhibits an unusual Nd enrichment which, in some cases, is sufficiently high that allanite is Nd dominant, thus a new mineral species, allanite-Nd.
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4

Thomas, Jay Bradley. "Melt Inclusion Geochemistry." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11262.

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Silicate melt inclusions (MI) are small samples of melt that are trapped during crystal growth at magmatic pressures and temperatures. The MI represent a sample of the melt that was isolated from the magma during host crystal growth. Thus, MI provide a valuable tool for constraining the magmatic history of igneous systems because they provide an unambiguous method to directly determine compositions of melts from which the host crystal grew. As such, coupled petrographic examination and geochemical analyses of MI and host crystals can reveal information about crystal/melt processes in igneous systems that are difficult (or impossible) to assess through conventional methods. Many studies have used MI to monitor large scale petrogenetic processes such as partial melting and fractional crystallization. The research presented below focuses on using MI to constrain processes that operate at the crystal/melt interface because MI are samples of melt that resided adjacent to the host crystal prior to entrapment as an inclusion. Chapter one addresses challenges associated with preparing small crystals containing MI for geochemical analysis. In chapter two trace element analyses of MI and the immediately adjacent host zircon crystals are used to determine zircon/melt partition coefficients. In chapter 3 the significance of boundary layer development adjacent to growing crystals is evaluated by comparing the trace element compositions of MI host crystals that have significantly different trace element mineral/melt partitioning behavior.
Ph. D.
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5

Bertram, Caroline Jane. "Rare earth elements and neodymium isotopes in the Indian Ocean." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277641.

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6

Tirone, Massimiliano. "Diffusion of rare earth elements in garnets and pyroxenes: Experiment, theory and applications." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280005.

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This thesis consists of three main chapters preceded by an introduction that discusses the importance of diffusion in minerals to constrain the geochemistry of various magmatic processes. The first chapter deals with the experimental technique and measurement of tracer element diffusion data in garnet and clinopyroxene. Self-diffusion coefficients of selected REE have been measured as a function of temperature (770°C-1050°) at 1 bar and oxygen fugacity (fO₂) corresponding to that defined by the iron-wustite buffer. The experimental results indicate small variations of diffusivity for REE in both garnet and clinopyroxene and an activation energy which is similar to the activation energy for diffusion of major components. In the second chapter the atomistic mechanism of Nd diffusion in garnet is investigated by molecular dynamics (MD) simulation. An optimization procedure based on genetic algorithm provides the semi-empirical coefficients that are used to reproduce the repulsive forces between atoms. Results from MD simulations at high pressure and temperature show that Schottky defect is the most favorable mechanism for vacancy formation in the intrinsic region. The preferred reaction to incorporate neodymium in the dodecahedral site involves transferring an iron atom to the octahedral site after removing the aluminum atom from the lattice site. A model of diffusion in the extrinsic region with a prescribed vacancy defect fraction in the garnet (10⁻⁴) also provides an acceptable result. The third chapter considers some of the potential applications of the REE diffusion data in garnet and clinopyroxene to magmatic processes. REE patterns obtained from the solution of a moving boundary problem shows that incompatible elements are more sensitive to disequilibration controlled by diffusion. Melt generated by disequilibrium melting is less enriched in incompatible elements than melt produced by an equilibrium melting process. Solution of a multiphase flow model, including the chemical transport equations with diffusion in a solid phase, permits a more realistic investigation of the disequilibrium melting process. During the ridge evolution the model predicts negligible effect of solid state diffusion on the geochemical evolution of the partial melt and the residual solid.
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7

Ngwenya, Bryne Tendelo. "Magmatic and post-magmatic geochemistry of phosphorus and rare earth elements in carbonatites." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306803.

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This study documents the magmatic, hydrothermal and supergene mineralogy and geochemistry of phosphorus and rare earth elements in carbonatite complexes using examples from Tundulu (Malawi), Sokli (Finland), Siilinjarvi (Finland) and Kaluwe (Zambia). In carbonatites, phosphorus averages 1-2% P20S and forms the minerals fluorapatite and monazite. Hydrothermal and supergene processes enrich fluorapatite in Na and REEs through vitusite-type exchanges which lead to formation of vitusite, belovite and britholite; and in CO2 through anti-francolite substitutions. The highest rare earth element contents are found in late-stage ankerite carbonatites or similar rocks of low temperature origin (T < S(XtC) and in hydrothermally altered rocks, where they occur mainly as fluorocarbonates or carbonates. Such minerals are consistent with the REEs having been transported in form of mixed fluoride-carbonate complexes. The mineral paragenesis in hydrothermal veins suggests that different fluorocarbonates precipitated depending on the activity of Ca supplied to the fluid by the wall rocks. The various minerals are modelled to form by simple combinations of calcite (CaCO:v and bastnaesite (REEC03F) molecules. A secondary characteristic feature of these reactions is that extreme heavy rare earth enrichment occurs if the wall rocks are apatite-rich. Petrogenetic modelling using REEs suggests that carbonatites are unlikely to be derived from carbonated silicate magmas by fractional crystallisation or liquid immiscibility. These findings are supported by ex solution temperatures of about 9S0·C recorded using the calcitedolomite geothermometer for quenched lapilli from the Kaluwe carbonatite.
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8

Ridley, Mark K. "Gradient ion chromatographic determination of rare earth elements in coal and fly ash." Master's thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/18597.

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Rare Earth Element (REE) determination in samples of coal and fly ash was undertaken by gradient high performance ion chromatography (HPIC). Ion chromatographic analysis requires that samples be in solution and that the matrix transition metals be removed. Coal samples, weighing 0.20g, were successfully dissolved in sealed pressure vessels in a microwave oven. Standard ashing procedures, followed by acid dissolution, were carried out to allow comparison with the microwave digestion technique. A lithium metaborate/tetraborate fusion and acid dissolution technique was used for the dissolution of fly ash. For the technique of REE determination the sample matrix was removed by off-line cation exchange. In an initial stage of the HPIC analysis the transition metals were removed by anion exchange using pyridine-2,6 dicarboxylic acid. The REE were then analysed using gradient elution of oxalic and diglycolic acid. Typically a 100μ1 volume of sample solution was employed for REE determination, but in the case of low ash (low REE) coal samples, prepared by microwave digestion, on-line concentration of 3-5 ml of sample, was necessary. The separated REE were reacted with 4-(2-pyridylazo)-resorcinol (PAR) and detected photometrically using a visible light detector at a wavelength of 520nm. Reproducibility for each REE was typically better than 5%CoV. Results from the analysis of coal and fly ash international standard reference materials were in acceptable agreement with values from alternative analytical procedures. Smooth, coherent trends obtained when the data were plotted on chondrite and "shale composite" normalised diagrams provided some support for the accuracy of the technique. The application of HPIC to the determination of REE in coals was demonstrated by the analysis of a new international reference coal sample, USGS CLB-1. Differences in REE concentrations between coal samples prepared by microwave digestion and ashing were observed. The HPIC analytical technique was also applied to the determination of REE in fly ash. The REE concentrations of fly ash from sequential electrostatic precipitators, from Lethabo and Kendal power stations, were determined to elucidate the behaviour of REE after the combustion of coal. REE concentrations increased through the sequential precipitators.
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9

Zhong, Shaojun. "Precipitation kinetics and partitioning of rare earth elements (REE) between calcite and seawater." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41198.

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A novel and simple "constant-addition" technique was used to study calcite precipitation kinetics and the partitioning of REE between calcite overgrowths and their parent seawater solutions under steady state conditions.
As a consequence of solute interactions in solution and at the growing mineral surface, the calcite precipitation mechanism in seawater is complex. It is dominated by the following reversible overall reaction: $ rm Ca sp{2+}+CO sbsp{3}{2-} rightleftharpoons CaCO sb3.$ A kinetic expression is proposed which describes the precipitation rate according to this reaction. A partial reaction order of 3 with respect to CO$ sb3 sp{2-}$ is obtained.
REE have a strong affinity for calcite and substitute for Ca$ sp{2+}$. REE partition coefficients in calcite overgrowths were calculated from their concentrations in the overgrowths and their parent solutions using a non-thermodynamic homogeneous model. The concentrations were determined by chelation and gradient ion chromatography (CGIC) using a revised procedure. REE partition coefficients decrease gradually with increasing REE atomic number. They are sensitive to changes in (REE): (Ca$ sp{2+}$) and the presence of O$ sb2$ in solution, but unaffected by the precipitation rate, $ rm lbrack CO sb3 sp{2-} rbrack$ or Pco$ sb2$ of the solution. The partitioning behaviour of REE is negatively correlated to the solubility of their respective carbonates and influenced by speciation, adsorption, and subsequent surface reactions (e.g., dehydration).
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10

Ramirez-Caro, Daniel. "Rare earth elements (REE) as geochemical clues to reconstruct hydrocarbon generation history." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16871.

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Анотація:
Master of Science
Department of Geology
Matthew Totten
The REE distribution patterns and total concentrations of the organic matter of the Woodford shale reveal a potential avenue to investigate hydrocarbon maturation processes in a source rock. Ten samples of the organic matter fraction and 10 samples of the silicate-carbonate fraction of the Woodford shale from north central Oklahoma were analyzed by methods developed at KSU. Thirteen oil samples from Woodford Devonian oil and Mississippian oil samples were analyzed for REE also. REE concentration levels in an average shale range from 170 ppm to 185 ppm, and concentration levels in modern day plants occur in the ppb levels. The REE concentrations in the organic matter of the Woodford Shale samples analyzed ranged from 300 to 800 ppm. The high concentrations of the REEs in the Woodford Shale, as compared to the modern-day plants, are reflections of the transformations of buried Woodford Shale organic materials in post-depositional environmental conditions with potential contributions of exchanges of REE coming from associated sediments. The distribution patterns of REEs in the organic materials normalized to PAAS (post-Archean Australian Shale) had the following significant features: (1) all but two out of the ten samples had a La-Lu trend with HREE enrichment in general, (2) all but two samples showed Ho and Tm positive enrichments, (3) only one sample had positive Eu anomalies, (4) three samples had Ce negative anomalies, although one was with a positive Ce anomaly, (5) all but three out of ten had MREE enrichment by varied degrees. It is hypothesized that Ho and Tm positive anomalies in the organic materials of the Woodford Shale are reflections of enzymic influence related to the plant physiology. Similar arguments may be made for the Eu and the Ce anomalies in the Woodford Shale organic materials. The varied MREE enrichments are likely to have been related to some phosphate mineralization events, as the Woodford Shale is well known for having abundant presence of phosphate nodules. The trend of HREE enrichment in general for the Woodford Shale organic materials can be related to inheritance from sources with REE-complexes stabilized by interaction between the metals and carbonate ligands or carboxylate ligands or both. Therefore, a reasonable suggestion about the history of the REEs in the organic materials would be that both source and burial transformation effects of the deposited organic materials in association with the inorganic constituents had an influence on the general trend and the specific trends in the distribution patterns of the REEs. This study provides a valuable insight into the understandings of the REE landscapes in the organic fraction of the Woodford Shale in northern Oklahoma, linking these understandings to the REE analysis of an oil generated from the same source bed and comparing it to oil produced from younger Mississippian oil. The information gathered from this study may ultimately prove useful to trace the chemical history of oils generated from the Woodford Shale source beds.
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Книги з теми "Rare earth element geochemistry"

1

Gschneidner, K. A. Handbook on the Physics and Chemistry of Rare Earths: High Temperature Rare Earths Superconductors - I. Burlington: Elsevier, 2000.

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Grosz, A. E. Rare earth elements in the Cason shale of northern Arkansas: A geochemical reconnaissance. Little Rock, Ark: Arkansas Geological Commission, 1995.

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Schijf, Johan. Aqueous geochemistry of the rare earth elements in marine anoxic basins. [Utrecht: Faculteit Aardwetenschappen der Rijksuniversiteit te Utrecht, 1992.

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Lipman, Peter W. Rare-earth-element compositions of Cenozoic volcanic rocks in the southern Rocky Mountains and adjacent areas. [Washington, D.C.]: Dept. of the Interior, U.S. Geological Survey, 1987.

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Lipman, Peter W. Rare-earth-element compositions of Cenozoic volcanic rocks in the southern Rocky Mountains and adjacent areas. Washington, DC: U.S. Geological Survey, 1987.

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6

Fournier, Robert O. Trace metals and major and rare earth elements in cuttings from five high-temperature wells in the northwest region of The Geysers, California, vapor-dominated geothermal system. [Menlo Park, CA]: Dept. of the Interior, U.S. Geological Survey, 1995.

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7

Singh, Yamuna. Rare Earth Element Resources: Indian Context. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-41353-8.

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8

Miller, W. Roger. Geochemical anomalies in the vicinity of the Three Rivers area, Otero Co., New Mexico. [Denver, CO]: U.S. Dept. of the Interior, U.S. Geological Survey, 1997.

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Viktorovich, Burkov Vladimir, ред. Redkozemelʹnye ėlementy v korakh vyvetrivanii͡a︡. Moskva: "Nauka", 1985.

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10

Sholkovitz, Edward Richard. A compilation of the rare earth element composition of rivers, estuaries and the oceans. Woods Hole, Mass: Woods Hole Oceanographic Institution, 1996.

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Частини книг з теми "Rare earth element geochemistry"

1

Brookins, Douglas G. "Yttrium and the Rare Earth Elements (REE)." In Eh-pH Diagrams for Geochemistry, 122–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73093-1_50.

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2

Burt, D. M. "Chapter 10. COMPOSITIONAL AND PHASE RELATIONS AMONG RARE EARTH ELEMENT MINERALS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 259–308. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-013.

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3

Mariano, A. N. "Appendix: CATHODOLUMINESENCE EMISSION SPECTRA OF RARE EARTH ELEMENT ACTIVATORS IN MINERALS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 339–50. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-015.

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4

Hanson, G. N. "Chapter 4. AN APPROACH TO TRACE ELEMENT MODELING USING A SIMPLE IGNEOUS SYSTEM AS AN EXAMPLE." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 79–98. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-007.

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5

Brookins, D. G. "Chapter 8. AQUEOUS GEOCHEMISTRY OF RARE EARTH ELEMENTS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 201–26. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-011.

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6

Grauch, R. I. "Chapter 6. RARE EARTH ELEMENTS IN METAMORPHIC ROCKS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 147–68. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-009.

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7

Haskin, L. A. "Chapter 9. RARE EARTH ELEMENTS IN LUNAR MATERIALS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 227–58. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-012.

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8

Mariano, A. N. "Chapter 11. ECONOMIC GEOLOGY OF RARE EARTH ELEMENTS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 309–38. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-014.

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9

Patchett, P. J. "Chapter 2. RADIOGENIC ISOTOPE GEOCHEMISTRY OF RARE EARTH ELEMENTS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 25–44. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-005.

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10

McDonough, W. F., and F. A. Frey. "Chapter 5. RARE EARTH ELEMENTS IN UPPER MANTLE ROCKS." In Geochemistry and Mineralogy of Rare Earth Elements, edited by Bruce R. Lipin and G. A. McKay, 99–146. Berlin, Boston: De Gruyter, 1989. http://dx.doi.org/10.1515/9781501509032-008.

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Тези доповідей конференцій з теми "Rare earth element geochemistry"

1

Wang, Xikai, Xiao-Ming Liu, and Xiaofeng Liu. "RARE EARTH ELEMENT GEOCHEMISTRY OF CENOZOIC CARBONATES DURING DOLOMITIZATION." In GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-369070.

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2

Manlove, Hunter Michelle. "RARE EARTH ELEMENT GEOCHEMISTRY OF VERTEBRATE FOSSILS FROM THE CRETACEOUS MORENO FORMATION, CALIFORNIA." In 51st Annual GSA South-Central Section Meeting - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017sc-289197.

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3

Mao, Longjiang, Jijing Du, Duowen Mo, Jinghong Yang, and Haibin Gu. "Rare Earth Elements Geochemistry of Ceramics Excavated from Tongguanyao Site, China." In International Conference on Advances in Energy, Environment and Chemical Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/aeece-15.2015.166.

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4

Hartono, B. M., M. H. H. Zajuli, A. N. Hidayati, B. Priadi, M. F. Sodiq, and A. Najili. "Trace and Rare Earth Element Geochemistry and Distribution in Mesozoic Formations in Singkawang Basin, West Borneo." In 3rd Asia Pacific Meeting on Near Surface Geoscience & Engineering. European Association of Geoscientists & Engineers, 2020. http://dx.doi.org/10.3997/2214-4609.202071026.

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5

Souza, E. S., R. J. L. Garcia, I. M. Abreu, H. J. P. S. Ribeiro, J. R. Cerqueira, and A. F. S. Queiroz. "Use of Transition and Rare Earth Elements in the Evaluation of the Sedimentary Paleoenvironment of Devonian Shales, Brazil." In 29th International Meeting on Organic Geochemistry. European Association of Geoscientists & Engineers, 2019. http://dx.doi.org/10.3997/2214-4609.201902925.

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6

Chirkova, E. A., N. A. Kharitonova, V. Yu Lavrushin, and G. A. Chelnokov. "GEOCHEMISTRY OF RARE-EARTH ELEMENTS IN THE MINERAL WATERS OF THE ELBRUS REGION." In The Geological Evolution of the Water-Rock Interaction. Buryat Scientific Center of SB RAS Press, 2018. http://dx.doi.org/10.31554/978-5-7925-0536-0-2018-425-429.

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Kuscu, Mustafa. "TRACE AND RARE EARTH ELEMENT GEOCHEMISTRY OF SHALES IN THE LATE TRIASSIC ISPARTACAY FORMATION, ANTALYA NAPPES, WESTERN TAURIDS, TURKEY." In 16th International Multidisciplinary Scientific GeoConference SGEM2016. Stef92 Technology, 2016. http://dx.doi.org/10.5593/sgem2016/b11/s01.083.

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8

Altay, Tulay. "TRACE AND RARE EARTH ELEMENT GEOCHEMISTRY OF THE UPPER MIOCENE-PLIOCENE LACUSTRINE EVAPORITES OF THE BOR-ULUKISLA BASIN (NIGDE, TURKEY)." In SGEM2011 11th International Multidisciplinary Scientific GeoConference and EXPO. Stef92 Technology, 2011. http://dx.doi.org/10.5593/sgem2011/s03.151.

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9

Mingguo Xiao, Xinguo Zhuang, Wei Yi, and Baocheng Wu. "Rare earth elements geochemistry of late permian mudstones in the Mount Huaying, east Sichuan Province, South China." In 2011 International Conference on Remote Sensing, Environment and Transportation Engineering (RSETE). IEEE, 2011. http://dx.doi.org/10.1109/rsete.2011.5965030.

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10

George, Sarah, Brian K. Horton, Julie Fosdick, Gilby Jepson, and Rebecca A. VanderLeest. "DETRITAL APATITE U-PB AGES AND TRACE AND RARE EARTH ELEMENT GEOCHEMISTRY RECORD CA. 100 MA CRUSTAL THICKENING IN THE SOUTHERN ANDES." In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-358755.

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Звіти організацій з теми "Rare earth element geochemistry"

1

Anglin, C. D. Rare Earth and Trace Element Geochemistry of Scheelites, Slave Province Gold Deposits. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1992. http://dx.doi.org/10.4095/133348.

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2

David, J., and C. Gariepy. Rare - Earth Element Geochemistry of Sedimentary Sequences From the Lower St - Lawrence, Quebec Appalachians. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/122482.

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3

Matte, S., M. Constantin, and R. Stevenson. Mineralogical and geochemical characterisation of the Kipawa syenite complex, Quebec: implications for rare-earth element deposits. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329212.

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The Kipawa rare-earth element (REE) deposit is located in the Parautochton zone of the Grenville Province 55 km south of the boundary with the Superior Province. The deposit is part of the Kipawa syenite complex of peralkaline syenites, gneisses, and amphibolites that are intercalated with calc-silicate rocks and marbles overlain by a peralkaline gneissic granite. The REE deposit is principally composed of eudialyte, mosandrite and britholite, and less abundant minerals such as xenotime, monazite or euxenite. The Kipawa Complex outcrops as a series of thin, folded sheet imbricates located between regional metasediments, suggesting a regional tectonic control. Several hypotheses for the origin of the complex have been suggested: crustal contamination of mantle-derived magmas, crustal melting, fluid alteration, metamorphism, and hydrothermal activity. Our objective is to characterize the mineralogical, geochemical, and isotopic composition of the Kipawa complex in order to improve our understanding of the formation and the post-formation processes, and the age of the complex. The complex has been deformed and metamorphosed with evidence of melting-recrystallization textures among REE and Zr rich magmatic and post magmatic minerals. Major and trace element geochemistry obtained by ICP-MS suggest that syenites, granites and monzonite of the complex have within-plate A2 type anorogenic signatures, and our analyses indicate a strong crustal signature based on TIMS whole rock Nd isotopes. We have analyzed zircon grains by SEM, EPMA, ICP-MS and MC-ICP-MS coupled with laser ablation (Lu-Hf). Initial isotopic results also support a strong crustal signature. Taken together, these results suggest that alkaline magmas of the Kipawa complex/deposit could have formed by partial melting of the mantle followed by strong crustal contamination or by melting of metasomatized continental crust. These processes and origins strongly differ compare to most alkaline complexes in the world. Additional TIMS and LA-MC-ICP-MS analyses are planned to investigate whether all lithologies share the same strong crustal signature.
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4

Piercey, S. J., and J. L. Pilote. Nd-Hf isotope geochemistry and lithogeochemistry of the Rambler Rhyolite, Ming VMS deposit, Baie Verte Peninsula, Newfoundland: evidence for slab melting and implications for VMS localization. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328988.

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New high precision lithogeochemistry and Nd and Hf isotopic data were collected on felsic rocks of the Rambler Rhyolite formation from the Ming volcanogenic massive sulphide (VMS) deposit, Baie Verte Peninsula, Newfoundland. The Rambler Rhyolite formation consists of intermediate to felsic volcanic and volcaniclastic rocks with U-shaped primitive mantle normalized trace element patterns with negative Nb anomalies, light rare earth element-enrichment (high La/Sm), and distinctively positive Zr and Hf anomalies relative to surrounding middle rare earth elements (high Zr-Hf/Sm). The Rambler Rhyolite samples have epsilon-Ndt = -2.5 to -1.1 and epsilon-Hft = +3.6 to +6.6; depleted mantle model ages are TDM(Nd) = 1.3-1.5 Ga and TDM(Hf) = 0.9-1.1Ga. The decoupling of the Nd and Hf isotopic data is reflected in epsilon-Hft isotopic data that lies above the mantle array in epsilon-Ndt -epsilon-Hft space with positive ?epsilon-Hft values (+2.3 to +6.2). These Hf-Nd isotopic attributes, and high Zr-Hf/Sm and U-shaped trace element patterns, are consistent with these rocks having formed as slab melts, consistent with previous studies. The association of these slab melt rocks with Au-bearing VMS mineralization, and their FI-FII trace element signatures that are similar to rhyolites in Au-rich VMS deposits in other belts (e.g., Abitibi), suggests that assuming that FI-FII felsic rocks are less prospective is invalid and highlights the importance of having an integrated, full understanding of the tectono-magmatic history of a given belt before assigning whether or not it is prospective for VMS mineralization.
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Manor, M. J., and S. J. Piercey. Whole-rock lithogeochemistry, Nd-Hf isotopes, and in situ zircon geochemistry of VMS-related felsic rocks, Finlayson Lake VMS district, Yukon. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328992.

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The Finlayson Lake district in southeastern Yukon is composed of a Late Paleozoic arc-backarc system that consists of metamorphosed volcanic, plutonic, and sedimentary rocks of the Yukon-Tanana and Slide Mountain terranes. These rocks host &amp;gt;40 Mt of polymetallic resources in numerous occurrences and styles of volcanogenic massive sulphide (VMS) mineralization. Geochemical and isotopic data from these rocks support previous interpretations that volcanism and plutonism occurred in arc-marginal arc (e.g., Fire Lake formation) and continental back-arc basin environments (e.g., Kudz Ze Kayah formation, Wind Lake formation, and Wolverine Lake group) where felsic magmatism formed from varying mixtures of crust- and mantle-derived material. The rocks have elevated high field strength element (HFSE) and rare earth element (REE) concentrations, and evolved to chondritic isotopic signatures, in VMS-proximal stratigraphy relative to VMS-barren assemblages. These geochemical features reflect the petrogenetic conditions that generated felsic rocks and likely played a role in the localization of VMS mineralization in the district. Preliminary in situ zircon chemistry supports these arguments with Th/U and Hf isotopic fingerprinting, where it is interpreted that the VMS-bearing lithofacies formed via crustal melting and mixing with increased juvenile, mafic magmatism; rocks that were less prospective have predominantly crustal signatures. These observations are consistent with the formation of VMS-related felsic rocks by basaltic underplating, crustal melting, and basalt-crustal melt mixing within an extensional setting. This work offers a unique perspective on magmatic petrogenesis that underscores the importance of integrating whole-rock with mineral-scale geochemistry in the characterization of VMS-related stratigraphy.
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6

Mueller, C., S. J. Piercey, M. G. Babechuk, and D. Copeland. Stratigraphy and lithogeochemistry of the Goldenville horizon and associated rocks, Baie Verte Peninsula, Newfoundland. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328990.

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The Goldenville horizon in the Baie Verte Peninsula is an important stratigraphic horizon that hosts primary (Cambrian to Ordovician) exhalative magnetite and pyrite and was a chemical trap for younger (Silurian to Devonian) orogenic gold mineralization. The horizon is overlain by basaltic flows and volcaniclastic rocks, is intercalated with variably coloured argillites and cherts, and underlain by mafic volcaniclastic rocks; the entire stratigraphy is cut by younger fine-grained mafic dykes and coarser gabbro. Lithogeochemical signatures of the Goldenville horizon allow it to be divided into high-Fe iron formation (HIF; &amp;gt;50% Fe2O3), low-Fe iron formation (LIF; 15-50% Fe2O3), and argillite with iron minerals (AIF; &amp;lt;15% Fe2O3). These variably Fe-rich rocks have Fe-Ti-Mn-Al systematics consistent with element derivation from varying mineral contributions from hydrothermal venting and ambient detrital sedimentation. Post-Archean Australian Shale (PAAS)-normalized rare earth element (REE) signatures for the HIF samples have negative Ce anomalies and patterns similar to modern hydrothermal sediment deposited under oxygenated ocean conditions. The PAAS-normalized REE signatures of LIF samples have positive Ce anomalies, similar to hydrothermal sediment deposited under anoxic to sub-oxic conditions. The paradoxical Ce behaviour is potentially explained by the Mn geochemistry of the LIF samples. The LIF have elevated MnO contents (2.0-7.5 weight %), suggesting that Mn from hydrothermal fluids was oxidized in an oxygenated water column during hydrothermal venting, Mn-oxides then scavenged Ce from seawater, and these Mn-oxides were subsequently deposited in the hydrothermal sediment. The Mn-rich LIF samples with positive Ce anomalies are intercalated with HIF with negative Ce anomalies, both regionally and on a metre scale within drill holes. Thus, the LIF positive Ce anomaly signature may record extended and particle-specific scavenging rather than sub-oxic/redox-stratified marine conditions. Collectively, results suggest that the Cambro-Ordovician Taconic seaway along the Laurentian margin may have been completely or near-completely oxygenated at the time of Goldenville horizon deposition.
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Williams, David L. Nondestructive, Bulk Rare Earth Element Measurement System for Coal. Office of Scientific and Technical Information (OSTI), March 2018. http://dx.doi.org/10.2172/1429156.

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8

Montross, Scott N., Circe A. Verba, and Keith Collins. Characterization of Rare Earth Element Minerals in Coal Utilization Byproducts. Office of Scientific and Technical Information (OSTI), July 2017. http://dx.doi.org/10.2172/1419423.

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9

Estep, Eric O. Countering China's Dominance in the Rare Earth Element Market System. Fort Belvoir, VA: Defense Technical Information Center, February 2012. http://dx.doi.org/10.21236/ada561277.

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10

Jacques, I. J., A. J. Anderson, and S. G. Nielsen. The geochemistry of thallium and its isotopes in rare-element pegmatites. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328983.

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The Tl isotopic and trace element composition of K-feldspar, mica, pollucite and pyrite from 13 niobium-yttrium-fluorine (NYF)-type and 14 lithium-cesium-tantalum (LCT)-type rare-element pegmatites was investigated. In general, the epsilon-205Tl values for K-feldspar in NYF- and LCT-type pegmatites increases with increasing magmatic fractionation. Both NYF and LCT pegmatites display a wide range in epsilon-205Tl (-4.25 to 9.41), which complicates attempts to characterize source reservoirs. We suggest 205Tl-enrichment during pegmatite crystallization occurs as Tl partitions between the residual melt and a coexisting aqueous fluid or flux-rich silicate liquid. Preferential association of 205Tl with Cl in the immiscible aqueous fluid may influence the isotopic character of the growing pegmatite minerals. Subsolidus alteration of K-feldspar by aqueous fluids, as indicated by the redistribution of Cs in K-feldspar, resulted in epsilon-205Tl values below the crustal average (-2.0 epsilon-205Tl). Such low epsilon-205Tl values in K-feldspar is attributed to preferential removal and transport of 205Tl by Cl-bearing fluids during dissolution and reprecipitation. The combination of thallium isotope and trace element data may be used to examine late-stage processes related to rare-element mineralization in some pegmatites. High epsilon-205Tl and Ga in late-stage muscovite appears to be a favorable indicator of rare-element enrichment LCT pegmatites and may be a useful exploration vector.
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