Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • Login
    View Item 
    •   DRUM
    • College of Computer, Mathematical & Natural Sciences
    • Geology
    • Geology Research Works
    • View Item
    •   DRUM
    • College of Computer, Mathematical & Natural Sciences
    • Geology
    • Geology Research Works
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    High-Precision Tungsten Isotopic Analysis by Multicollection Negative Thermal Ionization Mass Spectrometry Based on Simultaneous Measurement of W and 18O/16O Isotope Ratios for Accurate Fractionation Correction

    Thumbnail
    View/Open
    Accepted version of manuscript. (358.4Kb)
    No. of downloads: 142

    Date
    2016-01-11
    Author
    Trinquier, Anne
    Touboul, Mathieu
    Walker, Richard
    Citation
    10.1021/acs.analchem.5b04006
    DRUM DOI
    https://doi.org/10.13016/mjzg-cvbc
    Metadata
    Show full item record
    Abstract
    Determination of the 182W/184W ratio to a precision of ±5 ppm (2σ) is desirable for constraining the timing of core formation and other early planetary differentiation processes. However, WO − analysis by negative thermal ionization mass spectrometry normally results in a residual correlation between the instrumental-mass-fractionation-corrected 182W/184W and 183W/184W ratios that is attributed to mass-dependent variability of O isotopes over the course of an analysis and between different analyses. A second-order correction using the 183W/184W ratio relies on the assumption that this ratio is constant in nature. This may prove invalid, as has already been realized for other isotope systems. The present study utilizes simultaneous monitoring of the 18O/16O and W isotope ratios to correct oxide interferences on a per-integration basis and thus avoid the need for a double normalization of W isotopes. After normalization of W isotope ratios to a pair of W isotopes, following the exponential law, no residual W−O isotope correlation is observed. However, there is a nonideal mass bias residual correlation between 182W/iW and 183W/iW with time. Without double normalization of W isotopes and on the basis of three or four duplicate analyses, the external reproducibility per session of 182W/184W and 183W/184W normalized to 186W/183W is 5−6 ppm (2σ, 1−3 μg loads). The combined uncertainty per session is less than 4 ppm for 183W/184W and less than 6 ppm for 182W/184W (2σm) for loads between 3000 and 50 ng.
    URI
    http://hdl.handle.net/1903/26948
    Collections
    • Geology Research Works

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    Browse

    All of DRUMCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility