Lake Agassiz Final drainage event in the northwest North Atlantic
Lake Agassiz Final drainage event in the northwest North Atlantic
复制标题
阿加西湖北大西洋西北部最终排水事件
DOI：
10.1029/2007gl030396
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发表时间：
2007
影响因子：
5.2
通讯作者：
D. Piper
中科院分区：
文献类型：
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作者：
C. Hillaire‐Marcel;A. de Vernal;D. Piper
格陵兰冰芯记录的8.2 ka“气候”事件与由于晚冰期阿加西湖排水导致的大西洋经向翻转崩溃之间的因果关系存在争议。在这里，我们提供了来自北大西洋西北部洪水泄洪路线下游的记录，显示 9.5-8 ka 间隔期间发生了一系列事件。排水系统本身对应于校准的 8.35-8.5 ka 区间内沉积的双层富含碳酸盐的浊积岩。海面和深海流条件的替代指标并不表明北大西洋西北部发生显着的伴随变化。然而，该数据集支持这样的观点，即8.2ka“气候”事件可能代表了东北美洲陆地排水发生重大变化期间气候不稳定的表现之一，这是由于劳伦泰德冰盖的崩塌、随后海平面的快速上升和北大西洋温盐环流模式的大规模重组所致。
The 8.2 ka “climate” event recorded in Greenland ice cores is subject of debates with respect to causal linkage with a collapse of the Atlantic Meridional Overturning due to the drainage of the late‐glacial lake Agassiz. Here, we present records from the NW North Atlantic, down‐current the flood discharge route, showing that the 9.5–8 ka interval was marked by a succession of events. The drainage itself corresponds to a twin‐layer of carbonate‐rich turbidites deposited within the calibrated 8.35–8.5 ka interval. Proxies of sea‐surface and deep‐current conditions do not indicate significant concomitant changes in the NW North Atlantic. The dataset, however, supports the concept that the 8.2 ka “climate” event may represent one of the manifestations of climate instability during an interval with major changes of land drainage in NE America, due to the collapse of the Laurentide Ice Sheet, subsequent fast sea level rise and large scale reorganization of the North Atlantic thermohaline circulation pattern.