A perturbed hydrological cycle during Oceanic Anoxic Event 2
نویسندگان
چکیده
منابع مشابه
A continental-weathering control on orbitally driven redox-nutrient cycling during Cretaceous Oceanic Anoxic Event 2
The Cretaceous period (~145–65 m.y. ago) was characterized by intervals of enhanced organic carbon burial associated with increased primary production under greenhouse conditions. The global consequences of these perturbations, oceanic anoxic events (OAEs), lasted up to 1 m.y., but short-term nutrient and climatic controls on widespread anoxia are poorly understood. Here, we present a high-reso...
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Oceanic Anoxic Event 2 (OAE 2), occurring ∼94 million years ago, was one of the most extreme carbon cycle and climatic perturbations of the Phanerozoic Eon. It was typified by a rapid rise in atmospheric CO2, global warming, and marine anoxia, leading to the widespread devastation of marine ecosystems. However, the precise timing and extent to which oceanic anoxic conditions expanded during OAE...
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In Livello Bonarelli black shale deposited during Cretaceous Oceanic Anoxic Event 2 (OAE-2, ca. 94 Ma), nitrogen isotopic compositions of bulk sediments are mostly in a narrow range from –2.7 to –0.7‰. We also determined molecular distribution and nitrogen isotopic compositions of geoporphyrins extracted from the black shale. The nitrogen isotopic compositions of C32 Ni deoxophylloerythroetiopo...
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The investigated section cropping out in Kuh-e-Banesh, Zagros basin (southern Iran) is represented by limestone, Cherty beds and marllevels bearing abundant Planktonic foraminifers, radiolarian microfaunas, and ammonite imprints. For the first time, well to moderatelypreserved forms of Planktonic foraminifera have been extracted from black shale and marls levels. Extracted biota was studied wit...
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Biogeochemical and stable carbon isotopic analysis of black-shale sequences deposited during an Albian oceanic anoxic event (approximately 112 million years ago) indicate that up to 80 weight percent of sedimentary organic carbon is derived from marine, nonthermophilic archaea. The carbon-13 content of archaeal molecular fossils indicates that these archaea were living chemoautotrophically. The...
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ژورنال
عنوان ژورنال: Geology
سال: 2013
ISSN: 0091-7613,1943-2682
DOI: 10.1130/g34929.1