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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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