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Showing 1 to 8 of 8 for “"Oceanic Anoxic events"”.
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Development of a Borehole Log Signature for Oceanic Anoxic Events and Its Application to the Gulf of Mexico
Oceanic anoxic events (OAEs) are periods in Earth's history when oceans were depleted in dissolved oxygen and characterized by deposition of organic-rich sediments. The Oceanic Drilling Program (ODP) has drilled through OAEs in a number of areas worldwide, collecting core and borehole log data. …
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Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina
… zone euxinia; PZE) during mass extinctions and oceanic anoxic events. Here, the molecular fossil evidence for oxygenic photosynthesis and eukaryotes is reevaluated, where the results imply that currently existing lipid biomarkers are contaminants. Next, the stratigraphic distribution of green …
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Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina
… zone euxinia; PZE) during mass extinctions and oceanic anoxic events. Here, the molecular fossil evidence for oxygenic photosynthesis and eukaryotes is reevaluated, where the results imply that currently existing lipid biomarkers are contaminants. Next, the stratigraphic distribution of green …
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Faunal, sedimentological and geochemical indicators of dysoxia in Cretaceous marine sediments
… are characterised by the occurrence of 'Oceanic Anoxic Events' during which organic matter was extensively deposited in 'black shale' facies. Although diverse criteria for the recognition of low oxygen levels have been described previously they have not been fully calibrated. This project …
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Evaluating redox cycling across the Toarcian Oceanic Anoxic Event with implications for paleo-environmental reconstructions and organic matter sulfurization
… in habitability on Earth. Marine deoxygenation events, in particular, can result in changes in the carbon, sulfur, and iron cycles on our planet. Changes in these elemental cycles lead to distinctive variation in the chemical composition of seawater that is recorded in marine sediments that are …
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The Aptian-Albian ironstone of the Rapid Creek formation, Little Fish Creek, NWT: implications for Cretaceous Ocean Anoxic Events and critical mineral deposits
… climate may have been important for producing anoxic seawater enriched in Fe and Mn to the Blow Trough. Such an interpretation implies that the Aptian-Albian Oceanic Anoxic Event (OAE) 1b may have been regional rather than global in extent. Other OAE may also have been more localized than …
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Developing iodine proxies for oceanic oxygenation conditions during greenhouse episodes
… marine oxygen depletion during the so-called oceanic anoxic events (OAEs). How the water column oscillated between generally oxic conditions and local/global anoxia remains a challenging question, exacerbated by a lack of sensitive redox proxies, especially at the interface between oxic and …
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Controls on the accumulation of organic matter in the Eagle Ford Group, Central Texas, USA.
… conditions associated with the Pepper Formation, anoxic conditions associated with the Lower Eagle Ford Formation, suboxic conditions associated with most of the upper Eagle Fords, and then a return to normal marine conditions at the top of the Eagle Ford Formation. The high TOC content of the …