DOI: 10.1029/2017JF004428
Scopus记录号: 2-s2.0-85047788266
论文题名: A Sand-Gravel Gilbert Delta Subject to Base Level Change
作者: Chavarrías V. ; Blom A. ; Orrú C. ; Martín-Vide J.P. ; Viparelli E.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 5 起始页码: 1160
结束页码: 1179
语种: 英语
英文关键词: Gilbert delta
; image analysis
; mixed-sediment
; morphodynamics
; size stratification
Scopus关键词: aggradation
; entrainment
; image analysis
; morphodynamics
; sand and gravel
; sediment transport
; stratification
; Australia
; Gilbert River
; Queensland
英文摘要: Laboratory experiments were conducted on a sand-gravel Gilbert delta to gain insight on its dynamics under varying base level. Base level rise results in intensified aggradation over the topset, as well as a decrease in topset slope and topset surface coarsening, the signals of which migrate in an upstream direction. Preferential deposition of coarse sediment in the topset results in a finer load at the topset-foreset break, which creates a fine signature in the foreset deposit. Base level fall has the opposite effects. Entrainment of the topset mobile armor causes a coarsening of the load at the topset-foreset break and so a coarse signature in the foreset deposit. The entrainment of the topset substrate and fine top part of the foreset may follow, which causes a fining of the load and a fine signature in the foreset deposit. The fact that the upstream sediment supply requires a certain slope and bed surface texture to be transported downstream under quasi-equilibrium conditions counteracts the effects of base level change. This information travels in the downstream direction. In nature base level change is likely so slow that the upstream sediment load maintains the topset slope and bed surface texture and so keeps the topset in a quasi-equilibrium state. Base level change is therefore not expected to leave a clear signal in a mixed-sediment Gilbert delta other than a change in elevation of the topset-foreset interface. ©2018. The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/113967
Appears in Collections: 气候减缓与适应
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作者单位: Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands; Department of Civil Engineering, Technical University of Catalonia, Barcelona, Spain; Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC, United States
Recommended Citation:
Chavarrías V.,Blom A.,Orrú C.,et al. A Sand-Gravel Gilbert Delta Subject to Base Level Change[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(5)