Dataset Information

Cold spells in the Nordic Seas during the early Eocene Greenhouse.

ABSTRACT: The early Eocene (c. 56 - 48 million years ago) experienced some of the highest global temperatures in Earth's history since the Mesozoic, with no polar ice. Reports of contradictory ice-rafted erratics and cold water glendonites in the higher latitudes have been largely dismissed due to ambiguity of the significance of these purported cold-climate indicators. Here we apply clumped isotope paleothermometry to a traditionally qualitative abiotic proxy, glendonite calcite, to generate quantitative temperature estimates for northern mid-latitude bottom waters. Our data show that the glendonites of the Danish Basin formed in waters below 5 °C, at water depths of <300 m. Such near-freezing temperatures have not previously been reconstructed from proxy data for anywhere on the early Eocene Earth, and these data therefore suggest that regionalised cool episodes punctuated the background warmth of the early Eocene, likely linked to eruptive phases of the North Atlantic Igneous Province.

SUBMITTER: Vickers ML

PROVIDER: S-EPMC7501286 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Cold spells in the Nordic Seas during the early Eocene Greenhouse.

Vickers Madeleine L ML Lengger Sabine K SK Bernasconi Stefano M SM Thibault Nicolas N Schultz Bo Pagh BP Fernandez Alvaro A Ullmann Clemens V CV McCormack Paul P Bjerrum Christian J CJ Rasmussen Jan Audun JA Hougård Iben Winther IW Korte Christoph C

Nature communications 20200918 1

The early Eocene (c. 56 - 48 million years ago) experienced some of the highest global temperatures in Earth's history since the Mesozoic, with no polar ice. Reports of contradictory ice-rafted erratics and cold water glendonites in the higher latitudes have been largely dismissed due to ambiguity of the significance of these purported cold-climate indicators. Here we apply clumped isotope paleothermometry to a traditionally qualitative abiotic proxy, glendonite calcite, to generate quantitative ...[more]

PMID: 32948769

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Dataset Information

Cold spells in the Nordic Seas during the early Eocene Greenhouse.

Publications

Cold spells in the Nordic Seas during the early Eocene Greenhouse.

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