研究人员指出，在冰岛之下，地幔热柱中热地幔材料的跃动性上涌导致了北大西洋海床的上升。新成果发表在7月在线出版的《自然—地球科学》上。大约5600万年前，海底平面被临时性抬举，并在沉入海底之前因河水的冲蚀形成了海峡。
Ross Hartley和同事合作，利用地震数据成像了苏格兰东部的奥克尼-塞得兰群岛西部的古代地貌，今天，这一地带被埋藏在2公里厚的沉积岩之下。对这一地带的地形剖面模型和重建地貌中河流的分析显示，海底亚表面是在一系列的离散步骤中被抬高的，这可能是因地幔热柱中地幔材料温度的间隙性升高所造成。
在本期一篇相关的新闻和评述文章中， Philip Allen指出：“Hartley等展示了冰岛地幔热柱中热地幔材料脉动的向上和侧面的分布，与北大西洋海底上升模式之间的神奇关系。”(生物谷 Bioon.com)
doi:10.1038/ngeo1191
PMC:
PMID:1
Transient convective uplift of an ancient buried landscape
Ross A. Hartley; Gareth G. Roberts; Nicky White; Chris Richardson
Sedimentary basins in the North Atlantic Ocean preserve a record of intermittent uplift during Cenozoic times1. These variations in elevation are thought to result from temperature changes within the underlying Icelandic mantle plume2. When parts of the European continental shelf were episodically lifted above sea level, new landscapes were carved by erosion, but these landscapes then subsided and were buried beneath marine sediments3. Here, we use three-dimensional seismic data to reconstruct one of these ancient landscapes that formed off the northwest coast of Europe during the Palaeocene–Eocene Thermal Maximum. We identify a drainage network within the landscape and, by modelling the profiles of individual rivers within this network, we reconstruct the history of surface uplift. We show that the landscape was lifted above sea level in a series of three discrete steps of 200–400 m each. After about 1 million years of subaerial exposure, this landscape was reburied. We use the magnitude and duration of uplift to constrain the temperature and velocity of a mantle-plume anomaly that drove landscape formation. We conclude that pulses of hot, chemically depleted, mantle material spread out radially beneath the lithospheric plate at velocities of ~35 cm yr−1.
