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Bayon, Germain; Pierre, C; Etoubleau, Joel; Voisset, Michel; Cauquil, E; Marsset, Tania; Sultan, Nabil; Le Drezen, Eliane; Fouquet, Yves. |
We report on a reconnaissance analysis of the geochemical composition of authigenic carbonates and sediment samples collected from various seepage sites on the Niger deep-sea fan. Our aim has been to investigate whether evidence for the presence of authigenic carbonates and gas hydrates within sediments is discernible from solid-phase sediment geochemistry. We show that sedimentary Sr/Ca and Mg/Ca ratios can be used to infer the presence of authigenic aragonite (Sr-rich) and Mg-rich carbonate phases (high-Mg calcite, dolomite) in cold seep settings. Using Sr/Ca and Mg/Ca ratios, the proportion (wt.%) of authigenic carbonates in Niger Fan sediments can be calculated from a mixing model between sediment fractions of terrigenous material, biogenic calcite,... |
Tipo: Text |
Palavras-chave: Niger Delta; Gas hydrates; Cold seeps; Mg/Ca; Sr/Ca; Authigenic carbonates. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2696.pdf |
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