Triggering conditions and depositional characteristics of a disastrous debris flow event in Zhouqu city, Gansu Province, northwestern China
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Published:2011-11-02
Issue:11
Volume:11
Page:2903-2912
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ISSN:1684-9981
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Container-title:Natural Hazards and Earth System Sciences
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language:en
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Short-container-title:Nat. Hazards Earth Syst. Sci.
Author:
Tang C.,Rengers N.,van Asch Th. W. J.,Yang Y. H.,Wang G. F.
Abstract
Abstract. On 7 August 2010, catastrophic debris flows were triggered by a rainstorm in the catchments of the Sanyanyu and Luojiayu torrents, Zhouqu County, Gansu Province northwestern China. These two debris flows originated shortly after a rainstorm with an intensity of 77.3 mm h−1 and transported a total volume of about 2.2 million m3, which was deposited on an existing debris fan and into a river. This catastrophic event killed 1765 people living on this densely urbanised fan. The poorly sorted sediment contains boulders up to 3–4 m in diameter. In this study, the geomorphological features of both debris flow catchment areas are analyzed based on the interpretation of high-resolution remote sensing imagery combined with field investigation. The characteristics of the triggering rainfall and the initiation of the debris flow occurrence are discussed. Using empirical equations, the peak velocities and discharges of the debris flows were estimated to be around 9.7 m s−1 and 1358 m3 s−1 for the Sanyanyu torrent and 11 m s−1 and 572 m3 s−1 for the Luojiayu torrent. The results of this study contribute to a better understanding of the conditions leading to catastrophic debris flow events.
Publisher
Copernicus GmbH
Subject
General Earth and Planetary Sciences
Reference18 articles.
1. Costa, J. E.: Physical geomorphology of debris flows, in: Developments and Applications of Geomorphology, edited by: Costa, J. E. and Fleischer, P. J., New York, Springer-Verlag, 269–317, 1984. 2. Hu, K. H., Ge, Y. G., Cui, P., Guo, X. J., and Yang, W.: Preliminary Analysis of extra-large scale debris flow disaster in Zhouqu County of Gansu Province, J. Mountain Sci., 28, 628–634, 2010 (in Chinese). 3. Hungr, O., Morgan, G. C., and Kellerhals, R.: Quantitative analysis of debris torrent hazards for design of remedial measures, Can. Geotech. J., 21, 663–677, 1984. 4. Hürlimann, M., Copons, R., and Altimir, J.: Detailed debris flow hazard assessment in Andorra, A multidisciplinary approach, Geomorphology, 78, 359–372, 2006. 5. Jakob, M. and Hungr, O.: Introduction, in: Debris-flow Hazards and Related Phenomena, edited by: Jakob, M. and Hungr, O., Springer, Berlin, 1–8, 2005.
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