Curtin University Homepage
  • Library
  • Help
    • Admin

    espace - Curtin’s institutional repository

    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item

    Fluid-assisted zircon and monazite growth within a shear zone: A case study from Finnmark, Arctic Norway

    Access Status
    Fulltext not available
    Authors
    Kirkland, Chris
    Whitehouse, M.
    Slagstad, T.
    Date
    2009
    Type
    Journal Article
    
    Metadata
    Show full item record
    Citation
    Kirkland, C. and Whitehouse, M. and Slagstad, T. 2009. Fluid-assisted zircon and monazite growth within a shear zone: A case study from Finnmark, Arctic Norway. Contributions to Mineralogy and Petrology. 158 (5): pp. 637-657.
    Source Title
    Contributions to Mineralogy and Petrology
    DOI
    10.1007/s00410-009-0401-x
    ISSN
    0010-7999
    School
    Department of Applied Geology
    URI
    http://hdl.handle.net/20.500.11937/37742
    Collection
    • Curtin Research Publications
    Abstract

    The U-Pb ages, REE content, and oxygen isotopic composition of zircon rims developed within a major shear zone in the Kalak Nappe Complex (KNC), Arctic Norway have been determined along with the age of monazite crystals. Different generations of granitic veins have been distinguished based on both field criteria and monazite ages of 446 ± 3 and 424 ± 3 Ma. Within each of these veins, inherited zircon cores are mantled by homogeneous low CL-response zircon rims which yield a range of concordant U-Pb dates of ca. 470-360 Ma. Significant numbers of zircon rims coincide with the timing of monazite crystallization. The zircon rims have moderate light REE enrichment compared to cores, distinctive (Sm/La)n values of less than 12, and La between 0.3 and 10 ppm. This indicates free elemental exchange between newly formed zircon rims and the surrounding matrix. The rims have calculated accumulated alpha-radiation dosages corresponding with a crystalline structure and d18O values of 1‰. This implies rim crystallization directly from a zirconium-saturated hydrothermal fluid which was modified by some silicate melt. Growth of the zircon rims was prolonged and locally variable due to preferential fluid flow. A third type of zircon can be recognized, forming both rims and cores, with high alpha-radiation doses, and significant enrichment in La, Pr, and Eu. These are interpreted as low-temperature hydrothermally altered metamict zircons. The high volatile input and partial melting in the shear zone favoured prolonged zircon rim growth due to its ability to easily nucleate on inherited seeds. On the other hand, monazite, susceptible to dissolution and re-growth, crystallized in brief episodes, as has been predicted from theoretical phase diagrams. From a regional perspective, these results elucidate cryptic Ar-Ar cooling ages, providing the first record of a Late Ordovician heating and cooling phase within the KNC prior to the climactic Scandian collision. © Springer-Verlag 2009.

    Related items

    Showing items related by title, author, creator and subject.

    • Zoned Monazite and Zircon as Monitors for the Thermal History of Granulite Terranes: an Example from the Central Indian Tectonic Zone
      Bhowmik, S.; Wilde, Simon; Bhandari, A.; Sarbadhikari, A.B. (2014)
      The growth and dissolution behaviour of detrital, metamorphic and magmatic monazite and zircon during granulite-facies anatexis in pelitic and psammo-pelitic granulites and in garnetiferous granite from the southern margin ...
    • Th/U ratios in metamorphic zircon
      Yakymchuk, C.; Kirkland, Chris; Clark, Christopher (2018)
      The Th/U ratios of zircon crystals are routinely used to help understand their growth mechanism. Despite the wide application of Th/U ratios in understanding the geological significance of zircon U-Pb ages, the main ...
    • Neoproterozoic evolution and Cambrian reworking of ultrahigh temperature granulites in the Eastern Ghats Province, India
      Mitchell, R.; Johnson, Tim; Clark, Christopher; Gupta, S.; Brown, M.; Harley, S.; Taylor, Richard (2018)
      The time-scales and P–T conditions recorded by granulite facies metamorphic rocks permit inferences about the geodynamic regime in which they formed. Two compositionally heterogeneous cordierite–spinel-bearing granulites ...
    Advanced search

    Browse

    Communities & CollectionsIssue DateAuthorTitleSubjectDocument TypeThis CollectionIssue DateAuthorTitleSubjectDocument Type

    My Account

    Admin

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Follow Curtin

    • 
    • 
    • 
    • 
    • 

    CRICOS Provider Code: 00301JABN: 99 143 842 569TEQSA: PRV12158

    Copyright | Disclaimer | Privacy statement | Accessibility

    Curtin would like to pay respect to the Aboriginal and Torres Strait Islander members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Whadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.