Ocean redox structure across the Late Neoproterozoic Oxygenation Event: A nitrogen isotope perspective
نویسندگان
چکیده
منابع مشابه
Late-Neoproterozoic deep-ocean oxygenation and the rise of animal life.
Because animals require oxygen, an increase in late-Neoproterozoic oxygen concentrations has been suggested as a stimulus for their evolution. The iron content of deep-sea sediments shows that the deep ocean was anoxic and ferruginous before and during the Gaskiers glaciation 580 million years ago and that it became oxic afterward. The first known members of the Ediacara biota arose shortly aft...
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observations, to constrain the pattern of N2 fixation across the Pacific Ocean. N2 fixation introduces isotopically light atmospheric N2 from to the ocean (d N = 0‰) relative to the oceanic average near 5‰, which makes nitrogen isotopes suitable to infer patterns of N2 fixation. Including atmospheric iron limitation of diazotrophy in the model shifts the pattern of simulated N2 fixation from th...
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Anomalously high platinum group element concentrations have previously been reported for Upper Triassic deep-sea sediments, which are interpreted to be derived from an extraterrestrial impact event. Here we report the osmium (Os) isotope fingerprint of an extraterrestrial impact from Upper Triassic chert successions in Japan. Os isotope data exhibit a marked negative excursion from an initial O...
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ژورنال
عنوان ژورنال: Earth and Planetary Science Letters
سال: 2014
ISSN: 0012-821X
DOI: 10.1016/j.epsl.2014.03.042