Rapid ice sheet retreat triggered by ice stream debuttressing: Evidence from the North Sea
Rapid ice sheet retreat triggered by ice stream debuttressing: Evidence from the North Sea
复制标题
冰流首次出现引发冰盖快速退缩：来自北海的证据
DOI：
10.1130/g37652.1
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发表时间：
2016
期刊：
影响因子：
5.8
通讯作者：
B. O. Hjelstuen
中科院分区：
文献类型：
--
作者：
H. Sejrup;C. Clark;B. O. Hjelstuen
利用北海的高分辨率测深和浅层地震数据，我们绘制了迄今为止未知的冰川地貌，这些地貌连接并解决了该盆地第四纪地质历史中长期存在的空白。我们使用这些数据结合已公布的信息和沉积物岩心的日期重建的程度芬诺斯堪的纳维亚和英国冰盖（FIS和BIS）在北海的最后一个冰川期的最后阶段。得出的结论是，BIS占据了比以前提出的更大的北海部分，并且北海冰在大约18，500年前经历了戏剧性的解体。这是由挪威海峡冰流的接地线撤退引发的，它使邻近的冰块失去支撑，并导致BIS和FIS的解压缩，伴随着一个大型冰坝湖的排水。我们对事件的重建提供了一个机会，以提高对海洋冰盖解体的理解和建模，以及海洋环流和冰冻圈之间复杂的相互作用。
Using high-resolution bathymetric and shallow seismic data from the North Sea, we have mapped hitherto unknown glacial landforms that connect and resolve longstanding gaps in the Quaternary geological history of the basin. We use these data combined with published information and dates from sediment cores to reconstruct the extent of the Fennoscandian and British Ice Sheets (FIS and BIS) in the North Sea during the last phases of the last glacial stage. It is concluded that the BIS occupied a much larger part of the North Sea than previously suggested and that North Sea ice underwent a dramatic disintegration ~18,500 yr ago. This was triggered by grounding-line retreat of the Norwegian Channel Ice Stream, which debuttressed adjacent ice masses, and led to an unzipping of the BIS and FIS accompanied by drainage of a large ice-dammed lake. Our reconstruction of events provides an opportunity to improve understanding and modeling of the disintegration of marine-based ice sheets, and the complex interplay between ocean circulation and the cryosphere.