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    Please use this identifier to cite or link to this item: http://nthur.lib.nthu.edu.tw/dspace/handle/987654321/80875

    Title: The delta B-11 record in coral
    Authors: Shen, JJS;Wang, GS;Wei, KY
    教師: 沈君山
    Date: 2004
    Publisher: Meteoritical Society
    Relation: GEOCHIMICA ET COSMOCHIMICA ACTA, Meteoritical Society, Volume 68, Issue 11, Supplement, JUN 2004, Pages A350-A350
    Keywords: delta
    Abstract: The ocean has played a major role in controlling the variation of the CO2 content in the atmosphere. The partial pressure of CO2 (Pco2) is moderated by the CO2 concentration in oceans. The pH of seawater is governed by carbonate equilibration, so for a given pH value, it is possible to calculate the aqueous CO2 concentration and, thus, to make quantitative estimates of atmospheric Pco2. We were able to estimate pH of ancient seawater by measuring the boron isotope composition in the calcium carbonate (δ11Bcc) that was precipitated from it. This is because boron in seawater occurs as two species, B(OH)4‾ and B(OH)3, and their relative proportions are a function of pH. Boron isotopes are fractionated between these two species and the fractionation is highly pH dependent over the natural acidity range of seawater, such that δ11B in marine carbonates record the pH of the seawater from which they precipitated.
    Relation Link: http://www.meteoriticalsociety.org/
    URI: http://nthur.lib.nthu.edu.tw/dspace/handle/987654321/80875
    Appears in Collections:[沈君山 (1994-1997)] 期刊論文
    [物理系] 期刊論文

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