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On the oxygenation of the Archaean and Proterozoic oceans

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dc.contributor.author Banerjee A.
dc.contributor.author Słowakiewicz M.
dc.contributor.author Saha D.
dc.date.accessioned 2021-02-24T20:32:23Z
dc.date.available 2021-02-24T20:32:23Z
dc.date.issued 2020
dc.identifier.issn 0016-7568
dc.identifier.uri https://dspace.kpfu.ru/xmlui/handle/net/160775
dc.description.abstract © The Author(s), 2020. Published by Cambridge University Press. Modern-day ocean circulation behaves as a complex forced convective system that is characterized by the decrease in water temperature but increase in water density with depth. The dissolved oxygen content-which initially decreases due to biological oxygen demand- A lso increases with depth. In contrast to the present-day scenario, we propose that during the Archaean and Proterozoic eons inverted profiles could have developed such that, with depth, ocean water temperature increased and density and dissolved oxygen decreased. These inverted temperature and density profiles resulted in palaeo-ocean circulation behaving as a free convective system. It is proposed that this free convection, which may have been stable, or chaotic and subject to secondary instabilities, hindered the deep oxygenation of the palaeo-ocean. It may not be coincidental that the great oxygenation event (GOE) and Huronian glaciations are contemporaneous, in a similar way that the Neoproterozoic oxygenation event (NOE) is known to have been associated with glaciations. The global-scale external forcing required to switch the natural convective system to its present-day configuration is suggested to have been associated with Neoproterozoic glaciations and the subsequent lowering of ocean water salinity that accompanied them. We propose that this inverted the ocean water density gradient, allowing the oxygenation of the oceans for the first time. It is beyond the scope of this work to model the complex natural convection system, but we hope that geophysicists and numerical modellers will quantitatively evaluate the hypothesis proposed here to validate or refute our proposition.
dc.relation.ispartofseries Geological Magazine
dc.subject Archaean
dc.subject forced convection
dc.subject glaciation
dc.subject Keywords:
dc.subject natural convection
dc.subject ocean
dc.subject oxygenation
dc.subject Proterozoic
dc.title On the oxygenation of the Archaean and Proterozoic oceans
dc.type Article
dc.collection Публикации сотрудников КФУ
dc.source.id SCOPUS00167568-2020-SID85098254360


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  • Публикации сотрудников КФУ Scopus [22633]
    Коллекция содержит публикации сотрудников Казанского федерального (до 2010 года Казанского государственного) университета, проиндексированные в БД Scopus, начиная с 1970г.

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