Constraints on the Late Saalian to early Middle Weichselian ice sheet of Eurasia from field data and rebound modelling
Constraints on the Late Saalian to early Middle Weichselian ice sheet of Eurasia from field data and rebound modelling
复制标题
现场数据和回弹模型对欧亚大陆萨阿晚期到威瑟瑟早期早期冰盖的约束
DOI：
10.1080/03009480600781875
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发表时间：
2006
期刊：
影响因子：
2.2
通讯作者：
Per Moller
中科院分区：
文献类型：
--
作者：
K. Lambeck;A. Purcell;S. Funder;K. Kjær;E. Larsen;Per Moller
利用冰川反弹模型，我们反演了地壳反弹和海岸线位置的观测结果，以估计欧亚大陆北方主要冰川的冰厚度，并预测MIS-6晚期的古地形。140 kyr BP）至MIS‐ 4 e（早期中魏氏阶，约140 kyr BP）。64 kyr BP）。在萨利安晚期，冰延伸到北方欧洲和俄罗斯，从喀拉海到卡累利阿的中心有一个宽阔的圆顶，最大厚度为c。4500 m和C.海拔3500米。在芬兰上空出现了一个次级冰穹，冰厚和表面海拔分别为4000米和3000米。当冰开始撤退时，在早期Eemian的温暖阶段开始之前，从大西洋到乌拉尔发生了广泛的海洋洪水，一旦冰从乌拉尔撤退到泰梅尔半岛。波罗的海-白色海的连接预计将在大约129 kyr BP关闭，尽管俄罗斯北极的大部分地区直到Eemian结束时仍然被淹没。在stadial（MIS-5d，5 b，4）期间，最大的冰集中在卡拉-巴伦支海，厚度不超过c。1200米冰坝湖泊和岩床的海拔高度是预测的主要冰川阶段，并用于测试冰模型。预计西西伯利亚的大型湖泊将出现在萨利亚期结束时以及MIS-5d、5 b和4期间，湖泊水位、边缘位置和出口取决于冰层厚度和均衡调整等因素。在Saalian和MIS-5d，5 b期间，这些湖泊通过图尔盖山口溢出进入咸海，但在MIS-4期间，预计溢出发生在乌拉尔以北。乌拉尔山脉以西的古湖泊预测主要取决于卡拉冰盖是否堵塞了白色海。如果是这样的话，那么湖泊的水位是由多瑙河流域的地形控制的，溢流直接进入卡马-伏尔加河系统。科米湖MIS-5 b预测水位与实测水位的比较有利于白色海与巴伦支海接触的模型。
Using glacial rebound models we have inverted observations of crustal rebound and shoreline locations to estimate the ice thickness for the major glaciations over northern Eurasia and to predict the palaeo‐topography from late MIS‐6 (the Late Saalian at c. 140 kyr BP) to MIS‐4e (early Middle Weichselian at c. 64 kyr BP). During the Late Saalian, the ice extended across northern Europe and Russia with a broad dome centred from the Kara Sea to Karelia that reached a maximum thickness of c. 4500 m and ice surface elevation of c. 3500 m above sea level. A secondary dome occurred over Finland with ice thickness and surface elevation of 4000 m and 3000 m, respectively. When ice retreat commenced, and before the onset of the warm phase of the early Eemian, extensive marine flooding occurred from the Atlantic to the Urals and, once the ice retreated from the Urals, to the Taymyr Peninsula. The Baltic‐White Sea connection is predicted to have closed at about 129 kyr BP, although large areas of arctic Russia remained submerged until the end of the Eemian. During the stadials (MIS‐5d, 5b, 4) the maximum ice was centred over the Kara‐Barents Seas with a thickness not exceeding c. 1200 m. Ice‐dammed lakes and the elevations of sills are predicted for the major glacial phases and used to test the ice models. Large lakes are predicted for west Siberia at the end of the Saalian and during MIS‐5d, 5b and 4, with the lake levels, margin locations and outlets depending inter alia on ice thickness and isostatic adjustment. During the Saalian and MIS‐5d, 5b these lakes overflowed through the Turgay pass into the Aral Sea, but during MIS‐4 the overflow is predicted to have occurred north of the Urals. West of the Urals the palaeo‐lake predictions are strongly controlled by whether the Kara Ice Sheet dammed the White Sea. If it did, then the lake levels are controlled by the topography of the Dvina basin with overflow directed into the Kama‐Volga river system. Comparisons of predicted with observed MIS‐5b lake levels of Komi Lake favour models in which the White Sea was in contact with the Barents Sea.