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3D sedimentary architecture showing the inception of an Ice Age.

ABSTRACT: Northeast Atlantic climate shifted into the Quaternary Ice Age around 2.6?M?yr ago. Until now, however, the detailed changes associated with this inception of an Ice Age have remained obscure. New high-quality three-dimensional seismic data reveal a detailed geological record of buried surfaces, landforms and sedimentary architecture over vast parts of the Norwegian North Sea. Here, we show the sequence of near-coast geological events spanning the Northeast Atlantic inception of an Ice Age. We identify the location of immediate pre-glacial fluvially derived sandy systems where rivers from the Norwegian mainland built marine deltas. The stratigraphic position of a large submarine channel, formed by enhanced meltwater from initial build-up of local glaciers, is also shown. Finally, we document the transition to full ice-sheet growth over Scandinavia from the ice sheet's earliest position to the later pattern of debris-flow lobes reaching the present-day shelf edge.

SUBMITTER: Loseth H

PROVIDER: S-EPMC7293307 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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3D sedimentary architecture showing the inception of an Ice Age.

Løseth H H Dowdeswell J A JA Batchelor C L CL Ottesen D D

Nature communications 20200612 1

Northeast Atlantic climate shifted into the Quaternary Ice Age around 2.6 M yr ago. Until now, however, the detailed changes associated with this inception of an Ice Age have remained obscure. New high-quality three-dimensional seismic data reveal a detailed geological record of buried surfaces, landforms and sedimentary architecture over vast parts of the Norwegian North Sea. Here, we show the sequence of near-coast geological events spanning the Northeast Atlantic inception of an Ice Age. We i ...[more]

PMID: 32532994

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