自250万年前起，欧洲出现了广泛的海洋终端冰盖。

Extensive marine-terminating ice sheets in Europe from 2.5 million years ago.

作者信息

Rea Brice R, Newton Andrew M W, Lamb Rachel M, Harding Rachel, Bigg Grant R, Rose Phil, Spagnolo Matteo, Huuse Mads, Cater John M L, Archer Stuart, Buckley Francis, Halliyeva Maral, Huuse Jane, Cornwell David G, Brocklehurst Simon H, Howell John A

机构信息

School of Geosciences, University of Aberdeen, Aberdeen, UK.

School of Earth and Environmental Sciences, University of Manchester, Manchester, UK.

出版信息

Sci Adv. 2018 Jun 13;4(6):eaar8327. doi: 10.1126/sciadv.aar8327. eCollection 2018 Jun.

DOI:10.1126/sciadv.aar8327

PMID:29928693

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6007157/

Abstract

Geometries of Early Pleistocene [2.58 to 0.78 million years (Ma) ago] ice sheets in northwest Europe are poorly constrained but are required to improve our understanding of past ocean-atmosphere-cryosphere coupling. Ice sheets are believed to have changed in their response to orbital forcing, becoming, from about 1.2 Ma ago, volumetrically larger and longer-lived. We present a multiproxy data set for the North Sea, extending to over a kilometer below the present-day seafloor, which demonstrates spatially extensive glaciation of the basin from the earliest Pleistocene. Ice sheets repeatedly entered the North Sea, south of 60°N, in water depths of up to ~250 m from 2.53 Ma ago and subsequently grounded in the center of the basin, in deeper water, from 1.87 Ma ago. Despite lower global ice volumes, these ice sheets were near comparable in spatial extent to those of the Middle and Late Pleistocene but possibly thinner and moving over slippery (low basal resistance) beds.

摘要

欧洲西北部早更新世（距今258万年至78万年前）冰盖的几何形态限制条件不足，但对于增进我们对过去海洋 - 大气 - 冰冻圈耦合的理解至关重要。据信，冰盖对轨道强迫的响应发生了变化，从约120万年前开始，其体积变得更大，存在时间也更长。我们展示了一个北海的多指标数据集，该数据集延伸到现今海底以下一公里多深处，表明从早更新世最早时期起，该盆地就存在空间上广泛的冰川作用。从253万年前起，冰盖多次进入北纬60°以南的北海，水深可达约250米，随后从187万年前起在盆地中心更深的水域着陆。尽管全球冰量较低，但这些冰盖在空间范围上与中更新世和晚更新世的冰盖相近，但可能更薄，且在光滑（低底部阻力）的冰床上移动。