3D sedimentary architecture showing the inception of an Ice Age

• Published in: Nature Communications
• Main Authors: Løseth, H., Dowdeswell, J. A., Batchelor, C. L., Ottesen, D.
• Format: Text
• Language: English
• Published: Nature Publishing Group UK 2020
• Subjects: Article; Ice Sheet; Northeast Atlantic
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7293307/; http://www.ncbi.nlm.nih.gov/pubmed/32532994; https://doi.org/10.1038/s41467-020-16776-7

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.