Exsolution of thortveitite, yttrialite, and xenotime during low-temperature recrystallization of zircon from New Caledonia, and their significance for trace element incorporation in zircon
-
Carl Spandler
,
Jörg Hermann
Abstract
Recrystallized zircon grains in a phengite-epidote-chlorite schist from north-eastern New Caledonia contain as inclusions a mineral assemblage consisting of celadonite, kaolinite, quartz, Fe-oxy-hydroxide, smectite, chlorite, xenotime-(Y), thortveitite, yttrialite, and allanite-(Ce). This assemblage formed during low-temperature (<100 °C) seafloor alteration of a plagioclase-rich mafic rock and represents the first documented evidence of this alteration event in the high-P belt of northeastern New Caledonia. The survival of this low-temperature mineral paragenesis in zircon of a rock that has undergone subsequent eclogite-facies metamorphism testifies to the strength and value of zircon as a container for mineral inclusions. Thortveitite (Sc2Si2O7) and yttrialite (Y2Si2O7) inclusions in the altered zircon cores represent a new occurrence for these minerals and suggest that they may be more common than is currently recognized. The altered zircon cores generally have lower trace-element contents than the pristine igneous zircon cores and we suggest that thortveitite, yttrialite, and xenotime-(Y) formed as a result of trace-element expulsion from zircon during low-temperature recrystallization. Trace-element concentrations in the zircon cores indicate that trivalent cations (REE, Y, Sc) in zircon cannot be charge-balanced by xenotime substitution alone. Pentavalent cation concentrations (Nb, As) are also insufficient for charge balance. The presence of thortveitite (Sc2Si2O7) and yttrialite (Y2Si2O7) suggests that trivalent cations in zircon might be charge-balanced either by monovalent anions substituting for oxygen or by small monovalent cations such as H occurring interstitially in the zircon lattice.
© 2015 by Walter de Gruyter Berlin/Boston
Artikel in diesem Heft
- First-principle study of polytype structures of 1:1 dioctahedral phyllosilicates
- Calorimetry of liquids in the system Na2O-Fe2O3-SiO2
- A Mössbauer study of the oxidation state of Fe in silicate melts
- Nanometer-scale measurements of Fe3+/ΣFe by electron energy-loss spectroscopy: A cautionary note
- The most reduced rock from the moon, Apollo 14 basalt 14053: Its unique features and their origin
- Quantitative analysis of ammonium in biotite using infrared spectroscopy
- Lizardite-chlorite structural relationships and an inferred high-pressure lizardite polytype
- V oxidation state and coordination number in silicate glasses by XAS
- Structure of the fluorapatite (100)-water interface by high-resolution X-ray reflectivity
- Origin of diffuse superstructure reflections in labuntsovite-group minerals
- Isosymmetric structural phase transition of orthoenstatite: Molecular dynamics simulation
- Crystal nucleation in hydrous rhyolite: Experimental data applied to classical theory
- Investigation of polytypes in lepidolite using electron back-scattered diffraction
- Iron partitioning between basaltic melts and clinopyroxene as a function of oxygen fugacity
- The synthesis of zeolite-P, Linde Type A, and hydroxysodalite zeolites from paper sludge ash at low temperature (80 °C): Optimal ash-leaching condition for zeolite synthesis
- High-pressure viscometry of polymerized silicate melts and limitations of the Eyring equation
- Biological control on calcite crystallization: AFM investigation of coccolith polysaccharide function
- Order parameter variation through the C2/m-P21/m phase transition in cummingtonite
- Arsenate sorption on schwertmannite
- Evidence on the structure of synthetic schwertmannite
- Crystal-chemical characterization of tourmalines from the English Lake District: Electron-microprobe analyses and Mössbauer spectroscopy
- Crystal chemistry and paragenesis of compositionally unique (Al-, Fe-, Nb-, and Zr-rich) titanite from Afrikanda, Russia
- Site distribution of Fe2+and Fe3+in the axinite mineral group: New crystal-chemical formula
- Epidote-rich talc-kyanite-phengite eclogites, Sulu terrane, eastern China: P-T-fO₂estimates and the significance of the epidote-talc assemblage in eclogite
- Quantitative mineralogy of the Yukon River system: Changes with reach and season, and determining sediment provenance
- Exsolution of thortveitite, yttrialite, and xenotime during low-temperature recrystallization of zircon from New Caledonia, and their significance for trace element incorporation in zircon
- Mineralogical characterization and genesis of hydrothermal Mn oxides from the flank of the Juan the Fuca Ridge
- Synchrotron X-ray diffraction study of the structure of shafranovskite, K2Na3(Mn,Fe,Na)4[Si9(O,OH)27](OH)2⋅nH2O, a rare manganese phyllosilicate from the Kola peninsula, Russia
- Letter. Coupled cation and oxygen-isotope exchange between alkali feldspar and aqueous chloride solution
Artikel in diesem Heft
- First-principle study of polytype structures of 1:1 dioctahedral phyllosilicates
- Calorimetry of liquids in the system Na2O-Fe2O3-SiO2
- A Mössbauer study of the oxidation state of Fe in silicate melts
- Nanometer-scale measurements of Fe3+/ΣFe by electron energy-loss spectroscopy: A cautionary note
- The most reduced rock from the moon, Apollo 14 basalt 14053: Its unique features and their origin
- Quantitative analysis of ammonium in biotite using infrared spectroscopy
- Lizardite-chlorite structural relationships and an inferred high-pressure lizardite polytype
- V oxidation state and coordination number in silicate glasses by XAS
- Structure of the fluorapatite (100)-water interface by high-resolution X-ray reflectivity
- Origin of diffuse superstructure reflections in labuntsovite-group minerals
- Isosymmetric structural phase transition of orthoenstatite: Molecular dynamics simulation
- Crystal nucleation in hydrous rhyolite: Experimental data applied to classical theory
- Investigation of polytypes in lepidolite using electron back-scattered diffraction
- Iron partitioning between basaltic melts and clinopyroxene as a function of oxygen fugacity
- The synthesis of zeolite-P, Linde Type A, and hydroxysodalite zeolites from paper sludge ash at low temperature (80 °C): Optimal ash-leaching condition for zeolite synthesis
- High-pressure viscometry of polymerized silicate melts and limitations of the Eyring equation
- Biological control on calcite crystallization: AFM investigation of coccolith polysaccharide function
- Order parameter variation through the C2/m-P21/m phase transition in cummingtonite
- Arsenate sorption on schwertmannite
- Evidence on the structure of synthetic schwertmannite
- Crystal-chemical characterization of tourmalines from the English Lake District: Electron-microprobe analyses and Mössbauer spectroscopy
- Crystal chemistry and paragenesis of compositionally unique (Al-, Fe-, Nb-, and Zr-rich) titanite from Afrikanda, Russia
- Site distribution of Fe2+and Fe3+in the axinite mineral group: New crystal-chemical formula
- Epidote-rich talc-kyanite-phengite eclogites, Sulu terrane, eastern China: P-T-fO₂estimates and the significance of the epidote-talc assemblage in eclogite
- Quantitative mineralogy of the Yukon River system: Changes with reach and season, and determining sediment provenance
- Exsolution of thortveitite, yttrialite, and xenotime during low-temperature recrystallization of zircon from New Caledonia, and their significance for trace element incorporation in zircon
- Mineralogical characterization and genesis of hydrothermal Mn oxides from the flank of the Juan the Fuca Ridge
- Synchrotron X-ray diffraction study of the structure of shafranovskite, K2Na3(Mn,Fe,Na)4[Si9(O,OH)27](OH)2⋅nH2O, a rare manganese phyllosilicate from the Kola peninsula, Russia
- Letter. Coupled cation and oxygen-isotope exchange between alkali feldspar and aqueous chloride solution
