Multiple origins of zircons in jadeitite

Bin Fu, John W. Valley, Noriko T. Kita, Michael J. Spicuzza, Chad Paton, Tatsuki Tsujimori, Michael Bröcker, George E. Harlow

    Research output: Contribution to journalArticle

    50 Citations (Scopus)

    Abstract

    Jadeitites form from hydrothermal fluids during high pressure metamorphism in subduction environments; however, the origin of zircons in jadeitite is uncertain. We report ion microprobe analyses of δ18O and Ti in zircons, and bulk δ18O data for the jadeitite whole-rock from four terranes: Osayama serpentinite mélange, Japan; Syros mélange, Greece; the Motagua Fault zone, Guatemala; and the Franciscan Complex, California. In the Osayama jadeitite, two texturally contrasting groups of zircons are identified by cathodoluminescence and are distinct in δ18O: featureless or weakly zoned zircons with δ18O = 3.8 ± 0.6‰ (2 SD, VSMOW), and zircons with oscillatory or patchy zoning with higher δ18O = 5.0 ± 0.4‰. Zircons in phengite jadeitite from Guatemala and a jadeitite block from Syros have similar δ18O values to the latter from Osayama: Guatemala zircons are 4.8 ± 0.7‰, and the Syros zircons are 5.2 ± 0.5‰ in jadeitite and 5.2 ± 0.4‰ in associated omphacitite, glaucophanite and chlorite-actinolite rinds. The δ18O values for most zircons above fall within the range measured by ion microprobe in igneous zircons from oxide gabbros and plagiogranites in modern ocean crust (5.3 ± 0.8‰) and measured in bulk by laser fluorination of zircons in equilibrium with primitive magma compositions or the mantle (5.3 ± 0.6‰). Titanium concentrations in these zircons vary between 1 and 19 ppm, within the range for igneous zircons worldwide. Values of δ18O (whole-rock) ≅ δ18O (jadeite) and vary from 6.3 to 10.1‰ in jadeitites in all four areas. These values of δ18O and Ti are higher than predicted for hydrothermal zircons, and the δ18O values of most zircons are not equilibrated with the coexisting jadeite at reasonable metamorphic temperatures. We conclude that while some zircons may be hydrothermal in origin, a majority of the zircons studied are best explained as relic igneous crystals inherited from precursor rocks; they were not precipitated directly from hot aqueous fluids as previously assumed. Therefore, U-Pb ages from these zircons may date magmatic crystallization and do not establish the timing of high pressure metamorphism or hydrothermal activity.

    Original languageEnglish
    Pages (from-to)769-780
    Number of pages12
    JournalContributions to Mineralogy and Petrology
    Volume159
    Issue number6
    DOIs
    Publication statusPublished - 2010

    Fingerprint

    Guatemala
    zircon
    rocks
    fluorination
    fluid pressure
    Greece
    cathodoluminescence
    magma
    crusts
    Japan
    oceans
    ions
    Earth mantle
    titanium
    time measurement
    crystallization
    oxides
    fluids
    crystals
    lasers

    Keywords

    • California
    • Greece
    • Guatemala
    • Hydrothermal
    • Jadeite
    • Japan
    • Oxygen isotopes
    • SIMS
    • Zircon

    ASJC Scopus subject areas

    • Geochemistry and Petrology
    • Geophysics

    Cite this

    Fu, B., Valley, J. W., Kita, N. T., Spicuzza, M. J., Paton, C., Tsujimori, T., ... Harlow, G. E. (2010). Multiple origins of zircons in jadeitite. Contributions to Mineralogy and Petrology, 159(6), 769-780. https://doi.org/10.1007/s00410-009-0453-y

    Multiple origins of zircons in jadeitite. / Fu, Bin; Valley, John W.; Kita, Noriko T.; Spicuzza, Michael J.; Paton, Chad; Tsujimori, Tatsuki; Bröcker, Michael; Harlow, George E.

    In: Contributions to Mineralogy and Petrology, Vol. 159, No. 6, 2010, p. 769-780.

    Research output: Contribution to journalArticle

    Fu, B, Valley, JW, Kita, NT, Spicuzza, MJ, Paton, C, Tsujimori, T, Bröcker, M & Harlow, GE 2010, 'Multiple origins of zircons in jadeitite', Contributions to Mineralogy and Petrology, vol. 159, no. 6, pp. 769-780. https://doi.org/10.1007/s00410-009-0453-y
    Fu B, Valley JW, Kita NT, Spicuzza MJ, Paton C, Tsujimori T et al. Multiple origins of zircons in jadeitite. Contributions to Mineralogy and Petrology. 2010;159(6):769-780. https://doi.org/10.1007/s00410-009-0453-y
    Fu, Bin ; Valley, John W. ; Kita, Noriko T. ; Spicuzza, Michael J. ; Paton, Chad ; Tsujimori, Tatsuki ; Bröcker, Michael ; Harlow, George E. / Multiple origins of zircons in jadeitite. In: Contributions to Mineralogy and Petrology. 2010 ; Vol. 159, No. 6. pp. 769-780.
    @article{6e66f776679a4a5287d50abb263351e4,
    title = "Multiple origins of zircons in jadeitite",
    abstract = "Jadeitites form from hydrothermal fluids during high pressure metamorphism in subduction environments; however, the origin of zircons in jadeitite is uncertain. We report ion microprobe analyses of δ18O and Ti in zircons, and bulk δ18O data for the jadeitite whole-rock from four terranes: Osayama serpentinite m{\'e}lange, Japan; Syros m{\'e}lange, Greece; the Motagua Fault zone, Guatemala; and the Franciscan Complex, California. In the Osayama jadeitite, two texturally contrasting groups of zircons are identified by cathodoluminescence and are distinct in δ18O: featureless or weakly zoned zircons with δ18O = 3.8 ± 0.6‰ (2 SD, VSMOW), and zircons with oscillatory or patchy zoning with higher δ18O = 5.0 ± 0.4‰. Zircons in phengite jadeitite from Guatemala and a jadeitite block from Syros have similar δ18O values to the latter from Osayama: Guatemala zircons are 4.8 ± 0.7‰, and the Syros zircons are 5.2 ± 0.5‰ in jadeitite and 5.2 ± 0.4‰ in associated omphacitite, glaucophanite and chlorite-actinolite rinds. The δ18O values for most zircons above fall within the range measured by ion microprobe in igneous zircons from oxide gabbros and plagiogranites in modern ocean crust (5.3 ± 0.8‰) and measured in bulk by laser fluorination of zircons in equilibrium with primitive magma compositions or the mantle (5.3 ± 0.6‰). Titanium concentrations in these zircons vary between 1 and 19 ppm, within the range for igneous zircons worldwide. Values of δ18O (whole-rock) ≅ δ18O (jadeite) and vary from 6.3 to 10.1‰ in jadeitites in all four areas. These values of δ18O and Ti are higher than predicted for hydrothermal zircons, and the δ18O values of most zircons are not equilibrated with the coexisting jadeite at reasonable metamorphic temperatures. We conclude that while some zircons may be hydrothermal in origin, a majority of the zircons studied are best explained as relic igneous crystals inherited from precursor rocks; they were not precipitated directly from hot aqueous fluids as previously assumed. Therefore, U-Pb ages from these zircons may date magmatic crystallization and do not establish the timing of high pressure metamorphism or hydrothermal activity.",
    keywords = "California, Greece, Guatemala, Hydrothermal, Jadeite, Japan, Oxygen isotopes, SIMS, Zircon",
    author = "Bin Fu and Valley, {John W.} and Kita, {Noriko T.} and Spicuzza, {Michael J.} and Chad Paton and Tatsuki Tsujimori and Michael Br{\"o}cker and Harlow, {George E.}",
    year = "2010",
    doi = "10.1007/s00410-009-0453-y",
    language = "English",
    volume = "159",
    pages = "769--780",
    journal = "Contributions of Mineralogy and Petrology",
    issn = "0010-7999",
    publisher = "Springer Verlag",
    number = "6",

    }

    TY - JOUR

    T1 - Multiple origins of zircons in jadeitite

    AU - Fu, Bin

    AU - Valley, John W.

    AU - Kita, Noriko T.

    AU - Spicuzza, Michael J.

    AU - Paton, Chad

    AU - Tsujimori, Tatsuki

    AU - Bröcker, Michael

    AU - Harlow, George E.

    PY - 2010

    Y1 - 2010

    N2 - Jadeitites form from hydrothermal fluids during high pressure metamorphism in subduction environments; however, the origin of zircons in jadeitite is uncertain. We report ion microprobe analyses of δ18O and Ti in zircons, and bulk δ18O data for the jadeitite whole-rock from four terranes: Osayama serpentinite mélange, Japan; Syros mélange, Greece; the Motagua Fault zone, Guatemala; and the Franciscan Complex, California. In the Osayama jadeitite, two texturally contrasting groups of zircons are identified by cathodoluminescence and are distinct in δ18O: featureless or weakly zoned zircons with δ18O = 3.8 ± 0.6‰ (2 SD, VSMOW), and zircons with oscillatory or patchy zoning with higher δ18O = 5.0 ± 0.4‰. Zircons in phengite jadeitite from Guatemala and a jadeitite block from Syros have similar δ18O values to the latter from Osayama: Guatemala zircons are 4.8 ± 0.7‰, and the Syros zircons are 5.2 ± 0.5‰ in jadeitite and 5.2 ± 0.4‰ in associated omphacitite, glaucophanite and chlorite-actinolite rinds. The δ18O values for most zircons above fall within the range measured by ion microprobe in igneous zircons from oxide gabbros and plagiogranites in modern ocean crust (5.3 ± 0.8‰) and measured in bulk by laser fluorination of zircons in equilibrium with primitive magma compositions or the mantle (5.3 ± 0.6‰). Titanium concentrations in these zircons vary between 1 and 19 ppm, within the range for igneous zircons worldwide. Values of δ18O (whole-rock) ≅ δ18O (jadeite) and vary from 6.3 to 10.1‰ in jadeitites in all four areas. These values of δ18O and Ti are higher than predicted for hydrothermal zircons, and the δ18O values of most zircons are not equilibrated with the coexisting jadeite at reasonable metamorphic temperatures. We conclude that while some zircons may be hydrothermal in origin, a majority of the zircons studied are best explained as relic igneous crystals inherited from precursor rocks; they were not precipitated directly from hot aqueous fluids as previously assumed. Therefore, U-Pb ages from these zircons may date magmatic crystallization and do not establish the timing of high pressure metamorphism or hydrothermal activity.

    AB - Jadeitites form from hydrothermal fluids during high pressure metamorphism in subduction environments; however, the origin of zircons in jadeitite is uncertain. We report ion microprobe analyses of δ18O and Ti in zircons, and bulk δ18O data for the jadeitite whole-rock from four terranes: Osayama serpentinite mélange, Japan; Syros mélange, Greece; the Motagua Fault zone, Guatemala; and the Franciscan Complex, California. In the Osayama jadeitite, two texturally contrasting groups of zircons are identified by cathodoluminescence and are distinct in δ18O: featureless or weakly zoned zircons with δ18O = 3.8 ± 0.6‰ (2 SD, VSMOW), and zircons with oscillatory or patchy zoning with higher δ18O = 5.0 ± 0.4‰. Zircons in phengite jadeitite from Guatemala and a jadeitite block from Syros have similar δ18O values to the latter from Osayama: Guatemala zircons are 4.8 ± 0.7‰, and the Syros zircons are 5.2 ± 0.5‰ in jadeitite and 5.2 ± 0.4‰ in associated omphacitite, glaucophanite and chlorite-actinolite rinds. The δ18O values for most zircons above fall within the range measured by ion microprobe in igneous zircons from oxide gabbros and plagiogranites in modern ocean crust (5.3 ± 0.8‰) and measured in bulk by laser fluorination of zircons in equilibrium with primitive magma compositions or the mantle (5.3 ± 0.6‰). Titanium concentrations in these zircons vary between 1 and 19 ppm, within the range for igneous zircons worldwide. Values of δ18O (whole-rock) ≅ δ18O (jadeite) and vary from 6.3 to 10.1‰ in jadeitites in all four areas. These values of δ18O and Ti are higher than predicted for hydrothermal zircons, and the δ18O values of most zircons are not equilibrated with the coexisting jadeite at reasonable metamorphic temperatures. We conclude that while some zircons may be hydrothermal in origin, a majority of the zircons studied are best explained as relic igneous crystals inherited from precursor rocks; they were not precipitated directly from hot aqueous fluids as previously assumed. Therefore, U-Pb ages from these zircons may date magmatic crystallization and do not establish the timing of high pressure metamorphism or hydrothermal activity.

    KW - California

    KW - Greece

    KW - Guatemala

    KW - Hydrothermal

    KW - Jadeite

    KW - Japan

    KW - Oxygen isotopes

    KW - SIMS

    KW - Zircon

    UR - http://www.scopus.com/inward/record.url?scp=77952236123&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=77952236123&partnerID=8YFLogxK

    U2 - 10.1007/s00410-009-0453-y

    DO - 10.1007/s00410-009-0453-y

    M3 - Article

    AN - SCOPUS:77952236123

    VL - 159

    SP - 769

    EP - 780

    JO - Contributions of Mineralogy and Petrology

    JF - Contributions of Mineralogy and Petrology

    SN - 0010-7999

    IS - 6

    ER -