Divergence, convergence, and path dependency of paraglacial adjustment of alpine lateral moraine slopes
Divergence, convergence, and path dependency of paraglacial adjustment of alpine lateral moraine slopes
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高山侧碛斜坡冰缘调整的发散、收敛和路径依赖性
DOI：
10.1002/ldr.2983
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发表时间：
1990
影响因子：
4.7
通讯作者：
J. Eichel
中科院分区：
文献类型：
--
作者：
Draebing;J. Eichel
侧碛是重要的沉积物储存区，也是冰川前沿最具活力的地区之一。冰川退缩后，侧碛斜坡调整，因为它们的材料是由副冰川过程改造。以往的研究主要集中在冲沟的作用，然而，路径依赖的斜坡调整和侧碛斜坡的发散调整知之甚少。我们报告的数据，地貌和植被测绘，电阻率断层扫描，土壤水分测量，并在瑞士阿尔卑斯山的Turtmann冰川前陆冰缘过程是丰富的土壤质地分析。我们证明，冰旁斜坡调整表现出发散，收敛和路径依赖的行为。陡的近端冰碛斜坡首先受到冲沟作用的侵蚀。当冰碛斜坡达到30°的临界角时，固冲的重要性增加，固冲过程随后重新形成泥石流沉积物。相比之下，更温和的倾斜远坡低于阈值角度立即冰川退缩和微地貌反馈的结果，在更早开始的soliflavitation过程。我们确定了两种不同类型的草皮-银行soliflobulus叶的基础上，他们的时间发展和成因。1型叶发育于远冰碛斜坡上，并重塑冰碛物，2型叶则发育于侧冰碛坡脚处的泥石流沉积。这两种叶型只能通过实际形状来区分。随后的地貌过程的叠加可能导致等终和收敛的形式，如末次冰期的固体冰川片。我们的研究提供了一个现实的例子，如何在90至150年的冰缘土壤侵蚀迅速改造冰川沉积物。
Lateral moraines represent important sediment storages and are one of the most dynamic areas within glacier forelands. Following glacier retreat, lateral moraine slopes adjust as their material is reworked by paraglacial processes. Previous research focused primarily on the role of gullying, however, path‐dependent slope adjustment and divergent adjustment of lateral moraine slopes are poorly understood. We report data from geomorphic and vegetation mapping, electrical resistivity tomography, soil moisture measurements, and soil texture analysis acquired in the Turtmann glacier foreland in the Swiss Alps where periglacial processes are abundant. We demonstrate that paraglacial slope adjustment shows divergent, convergent, and path‐dependent behaviour. Steep proximal moraine slopes are first eroded by gullying processes. When moraine slopes reach a threshold angle of 30°, the importance of solifluction increases, and solifluction processes subsequently rework debris flow deposits. In contrast, more gently inclined distal slopes are below the threshold angle immediately following glacier retreat and biogeomorphic feedbacks result in an earlier onset of solifluction processes. We identified two different types of turf‐banked solifluction lobes based on their temporal development and genesis. Lobe Type 1 develops on distal moraine slopes and reworks glacial till, whereas Lobe Type 2 evolves from debris flow deposits at the footslopes of the lateral moraines. Both lobe types can only be differentiated using actual shape. Overprinting by subsequent geomorphic processes can result in equifinal and convergent forms such as solifluction sheets from the Last Glaciation. Our study provides an actualistic example of how paraglacial solifluction in 90 to 150 years rapidly reworks glacial sediments.
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冰坡调整中陡峭侧碛石的岩土控制
DOI：
10.1144/sp320.12
发表时间：
2009
期刊：
The Holocene
影响因子：
--
作者：
A. Curry;T. B. Sands;P. R. Porter
通讯作者：
P. R. Porter
象角的地貌过程和冻土条件（南极洲南设得兰群岛利文斯顿岛）
影响因子：
3.9
作者：
M. Oliva;J. Ruiz‐Fernández
通讯作者：
J. Ruiz‐Fernández
影响因子：
1.5
作者：
A. Curry;C. Ballantyne
通讯作者：
C. Ballantyne
霜冻蠕变和凝胶流动特性：回顾
影响因子：
2.3
作者：
J. B. Benedict
通讯作者：
J. B. Benedict
影响因子：
3.3
作者：
Eichel, Jana;Draebing, Daniel;Dikau, Richard
通讯作者：
Dikau, Richard