DOI: 10.1029/2018JF004622
Scopus记录号: 2-s2.0-85052809573
论文题名: Quantifying Sediment Transport Dynamics on Alluvial Fans From Spatial and Temporal Changes in Grain Size, Death Valley, California
作者: Brooke S.A.S. ; Whittaker A.C. ; Armitage J.J. ; D'Arcy M. ; Watkins S.E.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 8 起始页码: 2039
结束页码: 2067
语种: 英语
英文关键词: alluvial fans
; Death Valley
; fluvial geomorphology
; grain size
; sediment transport
; self-similarity
英文摘要: How information about sediment transport processes is transmitted to the sedimentary record remains a complex problem for the interpretation of fluvial stratigraphy. Alluvial fan deposits represent the condensed archive of sediment transport, which is at least partly controlled by tectonics and climate. For three coupled catchment-fan systems in northern Death Valley, California, we measure grain size across 12 well-preserved Holocene and late-Pleistocene surfaces, mapped in detail from field observations and remote sensing. Our results show that fan surfaces correlated to the late Pleistocene are, on average, 30–50% coarser than active or Holocene fan surfaces. We adopt a self-similar form of grain size distribution based on the observed stability of the ratio between mean grain size and standard deviation downstream. Using statistical analysis, we show that fan surface grain size distributions are self-similar. We derive a relative mobility function using our self-similar grain size distributions, which describes the relative probability of a given grain size being transported. We show that the largest mobile grain sizes are between 20 and 35 mm, a value that varies over time and is clearly lower in the Holocene than in the Pleistocene; a change we suggest is due to a drier climate in the Holocene. These results support recent findings that alluvial fan sedimentology can record past environmental change and that these landscapes are potentially sensitive to climatic change over a glacial-interglacial cycle. We demonstrate that the self-similarity methodology offers a means to explore changes in relative mobility of grain sizes from preserved fluvial deposits. ©2018. The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/113342
Appears in Collections: 气候减缓与适应
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作者单位: Department of Earth Science and Engineering, Imperial College London, London, United Kingdom; Institut de Physque du Globe de Paris, Dynamique des Fluides Geologiques, Paris, France; Institute of Earth and Environmental Science, University of Potsdam, Potsdam, Germany
Recommended Citation:
Brooke S.A.S.,Whittaker A.C.,Armitage J.J.,et al. Quantifying Sediment Transport Dynamics on Alluvial Fans From Spatial and Temporal Changes in Grain Size, Death Valley, California[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(8)