A new multi‐stage recession model for Proglacial Lake Humber during the retreat of the last British–Irish Ice Sheet
A new multi‐stage recession model for Proglacial Lake Humber during the retreat of the last British–Irish Ice Sheet
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最后一个英国-爱尔兰冰盖消退期间前冰川亨伯湖的新多阶段衰退模型
作者：
W. A. Fairburn;M. Bateman
与最后一个英国-爱尔兰冰原（BIIS）消退阶段有关的唯一最突出的湖泊是前冰川湖亨伯湖。本研究利用景观制图和发光测年相结合的方法，阐明了亨伯前冰期湖从最高海拔到消亡的修订区域历史。绘制亨伯湖多条线的结果现在最好用一个八阶段的衰退模型来描述。湖泊的侵蚀高地可以显示出BIIS推进后的时间，该推进在大约17 ka沉积了Skipsea Till，而新的OSL年龄显示，亨伯湖在15.5±0.8 ka接近消亡，表明可能是一个短暂存在的湖泊。多湖水位线的形成是由于林肯郡峡口向亨伯峡口的湖泊出口的转换，以及BIIS的振荡不止一次地阻塞后者，并随后在较低的海拔处形成的。水平或近水平岸线证实，在亨伯湖消亡期间，均衡调整并未发生，这表明BIIS在北海地区和约克谷的推进不仅是动态的，而且是短暂的。
The single most prominent lake associated with the retreat phase of the last British–Irish Ice Sheet (BIIS) was Proglacial Lake Humber. The present research elucidates a revised regional history of Proglacial Lake Humber from its maximum elevation to its demise using a combination of landscape mapping and luminescence dating. The results of mapping multiple Lake Humber strandlines are now best described by an eight‐stage recessional model. Erosional highstands of the lake can be shown to post‐date the BIIS advance that deposited the Skipsea Till at around 17 ka whereas new OSL ages show that Lake Humber was nearing its demise by 15.5±0.8 ka, indicating a possible short‐lived lake. Multiple lake level stands are attributed to the switching of lake outlets from the Lincolnshire Gap to the Humber Gap and to oscillations of the BIIS blocking the latter on more than one occasion and subsequently at a lower elevation with till. The horizontal or near‐horizontal shorelines confirm that isostatic adjustment did not occur during the demise of Lake Humber, indicating that BIIS advances in the North Sea region and Vale of York were not only dynamic but of short duration.