| Autor: |
M. J. Turuani, A.-M. Seydoux-Guillaume, A. T. Laurent, S. M. Reddy, S. L. Harley, D. Fougerouse, D. Saxey, S. Gouy, P. De Parseval, S. Reynaud, W. Rickard |
| Přispěvatelé: |
Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Curtin University [Perth], Planning and Transport Research Centre (PATREC), University of Edinburgh, Centre de microcaractérisation Raimond Castaing (Centre Castaing), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Laboratoire Hubert Curien (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Université Jean Monnet - Saint-Étienne (UJM), INSU-CNRS |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
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| Popis: |
Understanding radionuclides mass transfer mechanisms in monazite (LREEPO4) and the resulting features, from the micro-to the nanoscale, is critical to its use as a robust U-Th-Pb geochronometer. A detailed multi-scale characterization of discordant monazite grains from a granulite which records a polymetamorphic history, explores the mechanisms of Th and Pb mobility in crystals. Some monazite grains display Th-rich linear features (0.1-1 µm thick) associated with a chemically varied suite of amorphous silicate (±Al, Mg, Fe) phases or sulphur (e.g. FeS). They are interpreted as precipitates within monazite crystals. They formed during replacement mechanism of monazite through fluid interactions. Two generations of Pb*bearing nanophases exist supported by previous geochronological data. The shielding effect of garnet and rutilated quartz (host minerals), limiting fluid access, induces plentiful Pb*-bearing nanophases precipitation (fluid saturation enhanced) and limits Pb*-loss at the grainscale. This multi-scale study provides new insights for interpretations of meaningless geochronological information thanks to nanoscale investigations. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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