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DOI	10.1029/2018JF004815
	Fan-Surface Evidence for Debris-Flow Avulsion Controls and Probabilities, Saline Valley, California
	de Haas, T.1,2; Densmore, A. L.1; den Hond, T.2; Cox, N. J.1
通讯作者	de Haas, T.
来源期刊	JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
ISSN	2169-9003
EISSN	2169-9011
出版年	2019
卷号	124 期号:5 页码:1118-1138
英文摘要	Debris-flow fans form by shifts of the active channel, termed avulsions. Field and experimental evidence suggest that debris-flow avulsions may be induced by depositional lobes that locally plug a channel or superelevation of the channel bed above the surrounding fan surface, by analogy to fluvial fans. To understand debris-flow avulsion processes, we differentiate between these controls by quantifying the spatial distribution of debris-flow lobe and channel dimensions, along with channel-bed superelevation, on nine debris-flow fans in Saline Valley, California, USA. Channel beds are generally superelevated by 2-5 channel depths above the fan surface, and locally by more than 7 channel depths, thereby substantially exceeding superelevation on fluvial fans. Depositional-lobe thickness and channel depth decrease with distance from the fan apex, although both are highly variable across the fans. Median channel depths roughly correspond to the 50th-75th percentiles of lobe thicknesses, while minimum channel depths roughly correspond to the 10th-25th percentiles. In contrast, the thicknesses of lobes that have triggered avulsions roughly equal local channel depths and are on average twice as thick as the local median lobe thickness. The spatial correspondence between avulsion locations and thick lobe deposits, and the lack of correlation with channel-bed superelevation, leads us to infer that avulsions on these fans are mostly caused by thick lobes forming channel plugs. Although results may vary with climatic and tectonic setting, our findings indicate that avulsion hazard assessment on populated fans should include mapping and monitoring of channel depths relative to typical deposit thicknesses on a given fan.
英文关键词	debris flow alluvial fan avulsion Mojave Desert
类型	Article
语种	英语
国家	England ; Netherlands
开放获取类型	Green Accepted, hybrid, Green Published
收录类别	SCI-E
WOS记录号	WOS:000472611000004
WOS关键词	ALLUVIAL FANS ; OWENS-VALLEY ; SIZE DISTRIBUTION ; WHITE MOUNTAINS ; SIERRA-NEVADA ; GRAIN-SIZE ; MORPHOLOGY ; DYNAMICS ; CHANNELIZATION ; RECONSTRUCTION
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/217092
作者单位	1.Univ Durham, Dept Geog, Durham, England; 2.Univ Utrecht, Dept Phys Geog, Utrecht, Netherlands
推荐引用方式 GB/T 7714	de Haas, T.,Densmore, A. L.,den Hond, T.,et al. Fan-Surface Evidence for Debris-Flow Avulsion Controls and Probabilities, Saline Valley, California[J],2019,124(5):1118-1138.
APA	de Haas, T.,Densmore, A. L.,den Hond, T.,&Cox, N. J..(2019).Fan-Surface Evidence for Debris-Flow Avulsion Controls and Probabilities, Saline Valley, California.JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE,124(5),1118-1138.
MLA	de Haas, T.,et al."Fan-Surface Evidence for Debris-Flow Avulsion Controls and Probabilities, Saline Valley, California".JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE 124.5(2019):1118-1138.