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Cardinal, D; Alleman, Ly; Dehairs, F; Savoye, N; Trull, Tw; Andre, L. |
We analyzed delta(29) Si of dissolved silicate for eight water column profiles across the Southern Ocean ( south of Australia in spring 2001) from the Seasonal Ice Zone (SIZ) north to the Subantarctic Zone (SAZ), including the first isotopic compositions measured for Si-depleted seawaters. All profiles display mixed layer enrichments in heavy Si isotopes relative to deep water in accordance with preferential uptake of the light isotope by diatoms. As silicate levels decrease from the SIZ northward across the Polar Front Zone (PFZ) to the SAZ, surface and mesopelagic delta(29) Si signatures generally become progressively heavier, but the most Si-depleted SAZ waters do not exhibit delta(29) Si values heavier than in the PFZ. This intricacy appears to derive... |
Tipo: Text |
Palavras-chave: Δ29Si; Δ30Si; Diatoms; Spring Southern Ocean; Fractionation factor. |
Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00233/34424/32838.pdf |
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