Hillslope‐derived blocks retard river incision
Hillslope‐derived blocks retard river incision
复制标题
山坡衍生块体延缓河流切割
DOI：
10.1002/2016gl069262
复制
发表时间：
2016
影响因子：
5.2
通讯作者：
R. Anderson
中科院分区：
文献类型：
--
作者：
C. Shobe;G. Tucker;R. Anderson
最常见的限制拆离的河流下切模型忽略了沉积物对河流侵蚀的影响，然而山区河流的陡峭河段通常有大型（>1 m）块体的集群。我们认为，这种分布的块是一个自生的负反馈的表现，其中快速垂直河流切口陡峭相邻的山坡，提供块的通道。块通过屏蔽床和增强形状阻力来抑制切口。我们探索这种反馈与1-D通道到达模型中，块交付山坡取决于河流切割率。结果表明，切口依赖性阻滞输送可以解释科罗拉多博尔德溪的阻滞分布。与当前理论预测的速率相比，所提出的负反馈可能会显着减缓断点撤退、通道调整和景观响应。山坡衍生块体的影响可能会使从河流剖面提取基准面历史的工作复杂化。
The most common detachment‐limited river incision models ignore the effects of sediment on fluvial erosion, yet steep reaches of mountain rivers often host clusters of large (>1 m) blocks. We argue that this distribution of blocks is a manifestation of an autogenic negative feedback in which fast vertical river incision steepens adjacent hillslopes, which deliver blocks to the channel. Blocks inhibit incision by shielding the bed and enhancing form drag. We explore this feedback with a 1‐D channel‐reach model in which block delivery by hillslopes depends on the river incision rate. Results indicate that incision‐dependent block delivery can explain the block distribution in Boulder Creek, Colorado. The proposed negative feedback may significantly slow knickpoint retreat, channel adjustment, and landscape response compared to rates predicted by current theory. The influence of hillslope‐derived blocks may complicate efforts to extract base level histories from river profiles.
影响因子：
3.9
作者：
Hurst, Martin D.;Mudd, Simon M.;Yoo, Kyungsoo
通讯作者：
Yoo, Kyungsoo