Podrobnosti záznamu

    Stable calcium isotopic compositions of Hawaiian shield lavas: Evidence for recycling of ancient marine carbonates into the mantle
    Farkaš, Juraj
    Huang, Shichun
    Jacobsen, Stein
Typ dokumentu
    článek v periodiku
Zdrojový dokument - seriál
    Geochimica et Cosmochimica Acta
    Roč. 75, č. 17
Výraz tezauru
    calcium isotopes basalts Hawaiian mantle plume
Klíčové slovo
Abstrakt (anglicky)
   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.
    Česká geologická služba
Kód přispěvatele
    ČGS (RIV)
Zdrojový formát
Datum importu
    15. 10. 2014