Evolution of lakes and basins in northern Alaska and discussion of the thaw lake cycle
Evolution of lakes and basins in northern Alaska and discussion of the thaw lake cycle
复制标题
DOI：
10.1029/2006jf000531
复制
发表时间：
2007-05-03
影响因子：
3.9
通讯作者：
Shur, Yuri
中科院分区：
文献类型：
--
作者：
Jorgenson, M. Torre;Shur, Yuri
[1]我们根据地形剖面、土壤和地面冰调查、放射性碳测年、摄影测量分析和区域比较，对阿拉斯加北部中部沿海平原的湖泊盆地的发展进行了评估。我们的分析表明，湖泊演化比以前的研究理论要复杂得多，也没有那么周期性。在我们研究的地区，在最古老的地形上没有足够的地面冰来形成融化的湖泊，排干的湖盆边缘的冰的堆积不足以将地表抬升到接近原始地形条件，而且这一过程发生的速度太慢，不足以在全新世内形成“融化湖旋回”。因此，我们修订了湖泊和盆地发展的概念模型，使其与我们在大部分沿海平原下面的大片沙层上观察到的模式和过程保持一致。发展阶段包括：(1)凹陷的初始泛滥形成原生湖泊，(2)侧向侵蚀，沉积物的分选和重新分配，(3)随着水系网络的扩大，湖泊排水，(4)粉质中心和沙质边缘的差异冰沉积，(5)在富冰盆地的隆起中心形成二次融化湖泊，并沿低边缘充填池塘，以及(6)盆地稳定。
[1] We evaluated the development of lake basins on the central coastal plain of northern Alaska on the basis of topographic profiles, soil and ground ice surveys, radiocarbon dating, photogrammetric analysis, and regional comparisons. Our analysis reveals that lake evolution is much more complex and less cyclic than theorized by previous investigations. In the area we studied, there was insufficient ground ice in the oldest terrain to form thaw lakes, the aggradation of ice in the margins of drained lake basins was insufficient to heave the surface up to near original topographic conditions, and the process occurs at too slow a rate for a "thaw lake cycle'' to develop within the Holocene. Accordingly, we revised the conceptual model of lake and basin development to be consistent with the patterns and process we observed on the extensive sand sheets underlying most of the coastal plain. Developmental stages include ( 1) initial flooding of depressions to form primary lakes, ( 2) lateral erosion, with sorting and redistribution of sediments, ( 3) lake drainage as the stream network expands, ( 4) differential ice aggradation in silty centers and sandy margins, ( 5) formation of secondary thaw lakes in the heaved centers of ice-rich basins and infilling of ponds along the low margins, and ( 6) basin stabilization.