...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth Surface Processes and Landforms: The journal of the British Geomorphological Research Group >Supra-glacial deposition and flux of catastrophic rock-slope failure debris, south-central Alaska
【24h】

Supra-glacial deposition and flux of catastrophic rock-slope failure debris, south-central Alaska

机译：阿拉斯加中南部灾难性岩石斜坡破坏碎屑的超冰川沉积和通量

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The ongoing debate over the effects of global environmental change on Earth's cryosphere calls for detailed knowledge about process rates and their variability in cold environments. In this context, appraisals of the coupling between glacier dynamics and para-glacial erosion rates in tectonically active mountains remain rare. We contribute to filling this knowledge gap and present an unprecedented regional-scale inventory of supra-glacial sediment flux and hillslope erosion rates inferred from an analysis of 123 large (> 0·1km~2) catastrophic bedrock landslides that fell onto glaciers in the Chugach Mountains, Alaska, as documented by satellite images obtained between 1972 to 2008. Assuming these supra-glacial landslide deposits to be passive strain markers we infer minimum decadal-scale sediment yields of 190 to 7400tkm~(-2)yr~(-1) for a given glacier-surface cross-section impacted by episodic rock-slope failure. These rates compare to reported fluvial sediment yields in many mountain rivers, but are an order of magnitude below the extreme sediment yields measured at the snouts of Alaskan glaciers, indicating that the bulk of debris discharged derives from en-glacial, sub-glacial or ice-proximal sources. We estimate an average minimum para-glacial erosion rate by large, episodic rock-slope failures at 0·5-0·7mmyr~(-1) in the Chugach Mountains over a 50-yr period, with earthquakes likely being responsible for up to 73% of this rate. Though ranking amongst the highest decadal landslide erosion rates for this size of study area worldwide, our inferred rates of hillslope erosion in the Chugach Mountains remain an order of magnitude below the pace of extremely rapid glacial sediment export and glacio-isostatic surface uplift previously reported from the region.
机译：关于全球环境变化对地球冰冻圈影响的持续辩论要求对过程速率及其在寒冷环境中的可变性进行详细了解。在这种情况下，对在构造活跃的山区中冰川动力学与冰川副侵蚀率之间的耦合关系的评价仍然很少。我们为填补这一知识空白做出了贡献，并通过对123个落在Chugach冰川上的巨大（> 0·1km〜2）灾难性基岩滑坡的分析得出了前所未有的区域性超冰川沉积物通量和山坡侵蚀速率清单。根据1972年至2008年获得的卫星图像记录的阿拉斯加山脉。假定这些超冰川滑坡沉积物是被动应变标志，我们推断最低年代际沉积物产量为190至7400tkm〜（-2）yr〜（-1）对于给定的冰川表面横断面，由偶发的岩石-边坡破坏影响。这些比率与报告的许多山区河流的河流沉积物产量相比较，但比阿拉斯加冰川的口鼻处测得的极端沉积物产量低一个数量级，这表明排出的大部分碎片来自冰川，次冰川或冰层。 -近端来源。我们估计在50年的时间里，楚加奇山地的大型，偶发性岩石斜坡破坏在0·5-0·7mmyr〜（-1）处的平均最小冰川副侵蚀速率，地震可能是造成这种情况的主要原因。这个比率的73％。尽管在这个规模的研究区域中，十年滑坡侵蚀率位居全球前列，但我们推断出的楚加奇山丘陵山坡侵蚀率仍比先前报道的极快的冰川沉积物输出和冰川等静压地表上升速度低一个数量级。该区域。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号