Record details

Title
    Stable calcium isotopic compositions of Hawaiian shield lavas: Evidence for recycling of ancient marine carbonates into the mantle
Author
    Farkaš, Juraj
    Huang, Shichun
    Jacobsen, Stein
Language
    anglicky
Publication type
    článek v periodiku
Source title - serial
    Geochimica et Cosmochimica Acta
Vol./nr.
    Roč. 75, č. 17
Pages
    11
Year
    2011
Thesaurus term
    calcium isotopes basalts Hawaiian mantle plume
Keyword
    Ancient
    Calcium
    Carbonates
    Compositions
    Evidence
    Hawaiian
    Isotopic
    Lavas
    Mantle
    Marine
    Recycling
    Shield
    Stable
Abstract (in english)
   We report high-precision 44Ca/40Ca measurements of Hawaiian shield stage tholeiites. Our data reveal 0.3 per mil variation in their 44Ca/40Ca, which comprises 20% of the 44Ca/40Ca variation observed in global carbonates. The 44Ca/40Ca variation is correlated with Sr/Nb and 87Sr/86Sr, and this pattern is best explained by adding up to 4% ancient carbonate into the Hawaiian plume. Mass-balance calculations show that up to 40% of the Ca budget and 65% of the Sr budget in some Hawaiian (Makapuu-stage Koolau) lavas are derived from recycled carbonates. Our finding demonstrates, for the first time with the application of Ca isotopes, that ancient recycled carbonates are important components of mantle plumes which feed some of the largest terrestrial volcanoes. Thus, recycling of carbonates into the mantle is an essential part of the global Ca and C cycles.
Contributor
    Česká geologická služba
Contributor code
    ČGS (RIV)
Source format
    R
Import date
    15. 10. 2014