Geomorphic characteristics of hillslope and channelized debris flows: A case study in the Shitou area of central Taiwan

Chen, Jinn Chyi; Lin, Chin-Yuan; Wang, Lung Chang

doi:10.1007/s11629-009-0250-0

Cited by 17 publications

(8 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The identification of debris flows involved two basic stages. In the first stage, the possible locations of debris flow were identified from media reports (local newspapers, TV news), related documents and papers (Lin and Jeng, 2000;Cheng et al, 2005;Jan and Chen, 2005;Chen et al, 2009Chen et al, , 2012Chen, 2011), and interpretation of images, such as aerial photographs and satellite images (SPOT images before 2004; FORMOSAT2 images after 2004) to assess whether the event was classified as a debris flow. The second stage was to conduct a field investigation to confirm whether the event identified in the first stage qualified as a debris flow.…”

Section: Identification Of Debris Flow Eventsmentioning

confidence: 99%

Characteristics of rainfall triggering of debris flows in the Chenyulan watershed, Taiwan

Chen

Jan

Huang

2013

Nat. Hazards Earth Syst. Sci.

View full text Add to dashboard Cite

This paper reports the variation in rainfall characteristics associated with debris flows in the Chenyulan watershed, central Taiwan, between 1963 and 2009. The maximum hourly rainfall I_m, the maximum 24 h rainfall R_d, and the rainfall index RI (defined as the product R_dI_m) were analysed for each rainfall event that triggered a debris flow within the watershed. The corresponding number of debris flows initiated by each rainfall event (N) was also investigated via image analysis and/or field investigation. The relationship between N and RI was analysed. Higher RI of a rainfall event would trigger a larger number of debris flows. This paper also discusses the effects of the Chi-Chi earthquake (CCE) on this relationship and on debris flow initiation. The results showed that the critical RI for debris flow initiation had significant variations and was significantly lower in the years immediately following the CCE of 1999, but appeared to revert to the pre-earthquake condition about five years later. Under the same extreme rainfall event of RI = 365 cm² h⁻¹, the value of N in the CCE-affected period could be six times larger than that in the non-CCE-affected periods

show abstract

Section: Identification Of Debris Flow Eventsmentioning

confidence: 99%

Characteristics of rainfall triggering of debris flows in the Chenyulan watershed, Taiwan

Chen

Jan

Huang

2013

Nat. Hazards Earth Syst. Sci.

View full text Add to dashboard Cite

show abstract

“…The soil sediments entered the stream channels and cumulated on the streambed, and then moved directly downstream in the form of channelized debris flows in rainfall periods. Several channelized debris flows that occurred in the Chen-Yu-Lan watershed during the period from 1985 to 2008 and mentioned in articles (e.g., Yu and Chen 1987;Yu 1997a, b;Cheng et al 2000Cheng et al , 2003Cheng et al , 2005Lin and Jeng 2000;Fan et al 2002;Jan and Chen 2005;Chen et al 2009) were identified by aerial photograph interpretation and field investigation, as shown in Fig. 1.…”

Section: Introductionmentioning

confidence: 97%

“…In 2001, hundreds of debris flows occurred in central Taiwan (Cheng et al 2003(Cheng et al , 2005, resulting in over 100 people dead or missing and great damage to houses, roads, bridges, and dikes. The debris flows that occurred in central Taiwan can be classified as hillslope or channelized types (Chen et al 2009). Channelized types are discussed in this article.…”

Section: Introductionmentioning

confidence: 99%

Variability of impact of earthquake on debris-flow triggering conditions: case study of Chen-Yu-Lan watershed, Taiwan

Chen

2011

Environ Earth Sci

Self Cite

View full text Add to dashboard Cite

This study investigates the variations in the critical conditions for debris-flow occurrence before and after the Chi-Chi earthquake in the Chen-Yu-Lan watershed, Taiwan. Topographical and rainfall parameters such as the gully gradient, drainage area, rainfall intensity, cumulative rainfall, and rainfall duration in the Chen-Yu-Lan watershed were used to analyze the conditions of debris-flow occurrence over the past 25 years. A recovery equation was proposed on the basis of rainfall parameters and used to determine the variations in the critical line of rainfall that trigger debris flow after the earthquake and to evaluate the recovery period required for the rainfall threshold of debris-flow occurrence after the earthquake to return to that before the earthquake in the watershed. The critical line for the runoff parameter versus gully gradient in the watershed was also presented.

show abstract

“…Debris flow is a very rapid to extremely rapid flow of saturated debris in a deep channel, such as a gully or a ravine (Hungr et al 2001) and is usually initiated by the erosion and entrainment of hill slope and channel material by overland flow (e.g., Berti et al 2005; Thomas et al 2000;Hürlimann et al 2003;Godt and Coe 2007;Chen et al 2009) or sometimes triggered by outburst of dammed lake or reservoirs built in the channels (Zhou et al 1991;Godt and Coe 2007;Ni et al 2010bNi et al , 2012. As they have great velocity (several tens of km/h), long run-out distance (several km), and huge capacity to transport large and heavy rocks, they usually imply substantial destructive power and pose a significant hazard to people and infrastructure (Sepúlveda et al 2006;Tang et al 2011a, b, c).…”

Section: Introductionmentioning

confidence: 99%

Catastrophic debris flows triggered by a 4 July 2013 rainfall in Shimian, SW China: formation mechanism, disaster characteristics and the lessons learned

Zheng

Song

et al. 2014

Landslides

View full text Add to dashboard Cite

Catastrophic debris flows triggered by a 4 July 2013 rainfall in Shimian, SW China: formation mechanism, disaster characteristics and the lessons learned Abstract On 4 July 2013, three catastrophic debris flows occurred in the Hougou, Majingzi, and Xiongjia gullies in Shimian county and produced debris dams and river blockages, resulting in serious casualties and huge economic loss. Though debris flows have been identified prior to the catastrophic events, their magnitudes and destructive power were far beyond early recognition and hazard assessment. Our primary objective for this study was to explore the formation mechanism and typical characteristics and to summarize the lessons learned from these disastrous events in order to avoid the repeat of such disasters in the future. Based on field investigation and imagery interpretation of remote sensing carried out following the catastrophic events, four conclusions were drawn: (1) The catastrophic debris flows were initiated from surface-water runoff, and the triggering factor was attributed to the local intensive rainfall with an hourly intensity of more than 46.7mm. (2) Entrainment was the most important sedimentsupplying method for the debris flow occurrence, and the source materials transported by debris flows from the three gullies were estimated to be about 97×10 4 m 3 in volume altogether. (3) As surface-water runoff eroded and entrained hillslope and channel materials persistently, debris flows were characterized by intensive incision at upper or middle reaches and significant magnification effect in flow discharge and volume downstream. Corresponding peak discharge surveyed at the outlets of the Hougou, Majingzi, and Xiongjia gullies was estimated up to 751.0m 3 /s, 870.1m 3 /s, and 758.7m 3 /s, respectively. (4) Debris flows that occurred from the three gullies all belonged to viscous ones and the bulk densities were calculated more than 1.80g/cm 3 , indicating a huge carrying capacity and destructive impacting power. In addition, the lessons learned from the catastrophic events were summarized, including recognition and assessment on debris flow hazard and utilization of deposition fan. In this paper, prevention suggestions on debris flow prone valleys with high-vegetation coverage and low occurrence frequency were also put forward. The results of this study contribute to a better understanding on the initiation mechanism, dynamic characteristics, and disaster mitigation of debris flows initiated from intense rainfall and surface-water runoff in mountainous areas.

show abstract

Geomorphic characteristics of hillslope and channelized debris flows: A case study in the Shitou area of central Taiwan

Cited by 17 publications

References 4 publications

Characteristics of rainfall triggering of debris flows in the Chenyulan watershed, Taiwan

Characteristics of rainfall triggering of debris flows in the Chenyulan watershed, Taiwan

Variability of impact of earthquake on debris-flow triggering conditions: case study of Chen-Yu-Lan watershed, Taiwan

Catastrophic debris flows triggered by a 4 July 2013 rainfall in Shimian, SW China: formation mechanism, disaster characteristics and the lessons learned

Contact Info

Product

Resources

About