Field observations of debris-flow initiation processes on sediment deposits in a previous deep-seated landslide site

CORC > 成都山地灾害与环境研究所 > 中国科学院水利部成都山地灾害与环境研究所 > Journal of Mountain Science > Journal of Mountain Science-2016 > Vol13 No.2

	Field observations of debris-flow initiation processes on sediment deposits in a previous deep-seated landslide site
	Fumitoshi IMAIZUMI; Satoshi TSUCHIYA; Okihiro OHSAKA
刊名	Journal of Mountain Science
	2016-02
卷号	13 期号:2 页码:213-222
关键词	Debris flow Initiation zone Field monitoring Ohya landslide
ISSN号	1672-6316
通讯作者	Fumitoshi IMAIZUMI
英文摘要	Although information regarding the initiation processes of debris flows is important for the development of mitigationmeasures, field data regarding these processes are scarce. We conducted field observations of debris-flow initiation processes in the upper Ichinosawa catchment of the Ohya landslide, central Japan. On 19 June 2012, our video-camera monitoring systems recorded the moment of debris-flow initiation on channel deposits (nine surges) and talus slopes (eight surges). The initiation mechanisms of these surges were classified into three types by analyzing the video images: erosion by the surface flow, movement of deposits as a mass, and upward development of the fluid area. The first type was associated with the progress of surface flow from the upper stream on unsaturated channel deposits. The second type was likely caused by an increase in the pore water pressure associated with the rising in the groundwater level in channel deposits; a continuous water supply from the upper stream by the surface flow might have induced this saturation. The third type was associated with changes in the downstream topography caused by erosion. The flow velocity of most surges was less than 3 m s-1 and they usually stopped within 100 m from the initiation point. Surges with abundant pore fluid had a higher flow velocity (about 3 - 5 m s-1) and could travel for a longer duration. Our observations indicate that the surface flow plays an important role in the initiation of debris flows on channel deposits and talus slopes.
收录类别	SCI
语种	英语
内容类型	期刊论文
源URL	[http://ir.imde.ac.cn/handle/131551/14068]
专题	成都山地灾害与环境研究所_Journal of Mountain Science _Journal of Mountain Science-2016_Vol13 No.2
推荐引用方式 GB/T 7714	Fumitoshi IMAIZUMI,Satoshi TSUCHIYA,Okihiro OHSAKA. Field observations of debris-flow initiation processes on sediment deposits in a previous deep-seated landslide site[J]. Journal of Mountain Science,2016,13(2):213-222.
APA	Fumitoshi IMAIZUMI,Satoshi TSUCHIYA,&Okihiro OHSAKA.(2016).Field observations of debris-flow initiation processes on sediment deposits in a previous deep-seated landslide site.Journal of Mountain Science,13(2),213-222.
MLA	Fumitoshi IMAIZUMI,et al."Field observations of debris-flow initiation processes on sediment deposits in a previous deep-seated landslide site".Journal of Mountain Science 13.2(2016):213-222.