An alpine proglacial fluvial sediment budget
An alpine proglacial fluvial sediment budget
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高山前冰期河流沉积物收支
DOI：
10.1080/04353676.1990.11880322
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发表时间：
1990
影响因子：
1.5
通讯作者：
J. Warburton
中科院分区：
文献类型：
--
作者：
J. Warburton
在1987年消融季节，在瑞士南部瓦尔德H6 rens的Bas冰川d 'Arolla的冰前区进行了详细的沉积物转移过程，产沙量和通道变化的实地研究。产沙量的估计来自连续流量和悬浮泥沙浓度系列结合推移质输沙估计从沉积物收集器。河谷桑杜尔沉积物输运主导了冰前沉积物的输运。支流及山坡亦带来少量沉积物。通道变化是间歇性的，通道模式在消融季节从单线切换到多线再到单线。融水洪水造成了河道形态的灾难性变化。密集的实地测量（5月25日至7月30日）定义了一个冰前沉积物的预算表明，冰前沉积物来源的总流域产沙量的23%。在7月15日至18日短暂的融水泛滥期间，绝大多数的冰前沉积物（95%）从桑杜尔山谷中被侵蚀。用工作量来表示，预算表明，可以区分四个基本过程子集：（1）河道过程;（2）河谷桑杜尔（河道边缘）过程;（3）山坡过程;（4）坡洗。大规模的，罕见的洪水事件的主要控制释放的沉积物从冰前储存。
A detailed field study of sediment transfer processes, sediment yield and channel change was undertaken in the proglacial zone of the Bas Glacier d'Arolla, Val d'H6rens, southern Switzerland, during the 1987 ablation season. Sediment yield estimates were derived from continuous discharge and suspended sediment concentration series combined with bedload transport estimates from sediment traps. Valley sandur sediment transport dominated proglacial sediment transfers. Tributary streams and hillslopes contributed minor amounts of sediment. Channel change was episodic and channel pattern switched from single-thread to multi-thread to single-thread over the ablation season. Meltwater floods were responsible for catastrophic changes in channel form. Intensive field measurements (25 May 30 July) define a proglacial sediment budget which indicated that proglacial sediment sources contributed 23% to the total basin sediment yield. The overwhelming proportion of the proglacial sediment (95%) was eroded from the valley sandur during the brief period of meltwater flooding July 15-18. Expressed in terms of work, the budget suggests that four basic process subsets can be distinguished: (1) channel processes; (2) valley sandur (channel margin) processes; (3) hillslope processes, and (4) slopewash. Large magnitude, infrequent flood events are the dominant control on the release of sediment from proglacial storage.