globalchange  > 气候变化与战略
DOI: 10.1073/pnas.1911040117
论文题名:
How canyons evolve by incision into bedrock: Rainbow Canyon; Death Valley National Park; United States
作者: Zhang L.; Li T.; Wang G.; Kwang J.S.; Nittrouer J.A.; Fu X.; Parker G.
刊名: Proceedings of the National Academy of Sciences of the United States of America
ISSN: 0027-8424
出版年: 2020
卷: 117, 期:26
起始页码: 14730
结束页码: 14737
语种: 英语
英文关键词: Canyonc bedrock ; Incision ; Knickpoint ; Uplift
Scopus关键词: Article ; environmental parameters ; model ; priority journal ; river ; rock ; sediment ; steady state ; United States ; water flow
英文摘要: Incising rivers may be confined by low-slope, erodible hillslopes or steep, resistant sidewalls. In the latter case, the system forms a canyon. We present a morphodynamic model that includes the essential elements of a canyon incising into a plateau, including 1) abrasion-driven channel incision, 2) migration of a canyon-head knickpoint, 3) sediment feed from an alluvial channel upstream of the knickpoint, and 4) production of sediment by sidewall collapse. We calculate incision in terms of collision of clasts with the bed. We calculate knickpoint migration using a moving-boundary formulation that allows a slope discontinuity where the channel head meets an alluvial plateau feeder channel. Rather than modeling sidewall collapse events, we model long-term behavior using a constant sidewall slope as the channel incises. Our morphodynamic model specifically applies to canyon, rather than river–hillslope evolution. We implement it for Rainbow Canyon, CA. Salient results are as follows: 1) Sediment supply from collapsing canyon sidewalls can be substantially larger than that supplied from the feeder channel on the plateau. 2) For any given quasi-equilibrium canyon bedrock slope, two conjugate slopes are possible for the alluvial channel upstream, with the lower of the two corresponding to a substantially lower knickpoint migration rate and higher preservation potential. 3) Knickpoint migration occurs at a substantially faster time scale than regrading of the bedrock channel itself, underlying the significance of disequilibrium processes. Although implemented for constant climactic conditions, the model warrants extension to long-term climate variation. © 2020 National Academy of Sciences. All rights reserved.
Citation statistics:
被引频次[WOS]:8   [查看WOS记录]     [查看WOS中相关记录]
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164146
Appears in Collections:气候变化与战略

Files in This Item:

There are no files associated with this item.


作者单位: Zhang, L., Department of Civil and Environmental Engineering, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, 100086, China, School of Water Resources and Electric Power, Qinghai University, Xining, 810016, China; Li, T., State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, 100086, China, School of Water Resources and Electric Power, Qinghai University, Xining, 810016, China; Wang, G., State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, 100086, China, School of Water Resources and Electric Power, Qinghai University, Xining, 810016, China; Kwang, J.S., Department of Civil and Environmental Engineering, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States, Department of Geosciences, University of Massachusetts, Amherst, MA 01003, United States; Nittrouer, J.A., Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77045, United States; Fu, X., State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, 100086, China; Parker, G., Department of Civil and Environmental Engineering, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States, Department of Geology, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States

Recommended Citation:
Zhang L.,Li T.,Wang G.,et al. How canyons evolve by incision into bedrock: Rainbow Canyon; Death Valley National Park; United States[J]. Proceedings of the National Academy of Sciences of the United States of America,2020-01-01,117(26)
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Zhang L.]'s Articles
[Li T.]'s Articles
[Wang G.]'s Articles
百度学术
Similar articles in Baidu Scholar
[Zhang L.]'s Articles
[Li T.]'s Articles
[Wang G.]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Zhang L.]‘s Articles
[Li T.]‘s Articles
[Wang G.]‘s Articles
Related Copyright Policies
Null
收藏/分享
所有评论 (0)
暂无评论
 

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.