Suboxic diagenesis in banded iron formations
نویسندگان
چکیده
منابع مشابه
banded iron - formations , Weld Range , Western Australia
There are two basic Fe-rich lithologies at Weld Range: (l) banded iron-formation containing minnesotaite, siderite, quarlz,magnetite, greenalite, stilpnomelane, pyrite, and chamosite with trace amounts of pyrrhotite, arsenopyrite, chalcopyrite, apatite, and rockbridgeite; Q) Fe-shale. which occurs as laminated 2-30cm-thick bands within banded iron-formation, containing chamosite, stilpnomelane,...
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Banded iron formations (BIFs) record a time of extensive Fe deposition in the Precambrian oceans, but the sources and pathways for metals in BIFs remain controversial. Here, we present Fe- and Nd-isotope data that indicate two sources of Fe for the large BIF units deposited 2.5 billion y ago. High-εNd and -δ(56)Fe signatures in some BIF samples record a hydrothermal component, but correlated de...
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The effect of hydrogen on the rate of phototrophic Fe(II) oxidation by two species of purple bacteria was measured at two different bicarbonate concentrations. Hydrogen slowed Fe(II) oxidation to varying degrees depending on the bicarbonate concentration, but even the slowest rate of Fe(II) oxidation remained on the same order of magnitude as that estimated to have been necessary to deposit the...
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ژورنال
عنوان ژورنال: Nature
سال: 1984
ISSN: 0028-0836,1476-4687
DOI: 10.1038/309340a0