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![21 Filling curve for Tangjiashan rockslide-dammed lake showing rise in pool level after damming on May 12, 2008. Excavation of spillway lowered maximum lake level by 12 m, equivalent to 73 Mm 3 of storage (based on data in [177] and [176])](profile/Alexander-Strom-2/publication/225141323/figure/fig18/AS:451108456931334@1484564046317/Filling-curve-for-Tangjiashan-rockslide-dammed-lake-showing-rise-in-pool-level-after.png)
21 Filling curve for Tangjiashan rockslide-dammed lake showing rise in pool level after damming on May 12, 2008. Excavation of spillway lowered maximum lake level by 12 m, equivalent to 73 Mm 3 of storage (based on data in [177] and [176])
Source publication
The formation and behaviour of natural and artificial rockslide dams are reviewed to update the well-known work of Costa and
Schuster [1]. Rockslide dams block surface drainage to form upstream lakes. They may occur naturally due to landslides or
as a result of engineered rock slope failure. As evidenced by the 2010 Hunza event (Pakistan), the stab...
Citations
... Landslide dams, as a natural hazard, are ubiquitous worldwide and often cause great harm to the properties and lives of people over relatively large areas and extended periods, by inundating upstream areas and flooding downstream areas [7][8][9][10][11][12][13][14][15][16]. Many catastrophic landslide dam breach events have occurred on the eastern margin of the Qinghai-Tibet Plateau. ...
Landslide dams, especially stable landslide dams, have been recognised as important contributors to regional geomorphological evolution. The eastern edge of the Tibetan Plateau provides good conditions for the formation of stable landslide dams. To identify stable landslide dams on the eastern margin of the Tibetan Plateau, the Google Earth Engine (GEE) was first used to map water surfaces in the study area. Then, stable landslide dams were identified using high-precision remote sensing images provided by Google Earth. A field investigation and a sampling of typical stable landslide dams were also adopted to characterise the landslide dams. The results show that 101 stable landslide dams are present in the study area, covering an area of 27.75 × 104 km2. There are four types of stable landslide dams, as follows: (1) landslides, (2) rock avalanches, (3) moraines, and (4) debris flows. The morphological parameters of a dam, which include dam height, dam width, dam volume, and catchment area, can be fitted with different relationship curves, with respect to the number of landslide dams. The source areas of landslide dams are generally located in the upper-middle and upper sections of adjacent mountains. The stability of a landslide dam is mainly controlled by the structure of the dam and the relationship between the dam volume and catchment area. Structurally, large rocks with large particle sizes are difficult to activate using river water and the large gaps between the rocks provide sufficient channels for the flow of river water. In regard to the relationship between the dam volume and catchment area, a river with a small catchment area in the study area is commonly blocked by a large dam volume. This study provides a unique opportunity to study the spatial distribution and clarify the factors influencing the stability of stable landslide dams.
... The landslides significantly affect mountainous countries like Nepal, India, Switzerland, Japan, Canada, New Zealand, USA, and China (Lateltin et al. 2005;Yin et al 2009;Evans et al. 2011;Bhandary et al. 2013;Dhungana et al. 2023;Xiao et al. 2023). Prakasam et al. (2021) estimated the damages caused by the Himalayan landslides to cost more than one billion US Dollar in economic terms along with more than 200 deaths every year, accounting for about 30% of the total such worldwide losses. ...
Introduction
The rock avalanches are a frequent and disruptive phenomenon in the Himalayas and other mountain chains. To minimize future losses, it is essential to investigate the engineering geological causative factors and mechanism of these mass wasting events.
Study area
The present work is aimed at assessing the failure mechanism of the disastrous 2014 Jure rock avalanche along Araniko Highway, Northern Nepal. The event had blocked the Sunkoshi River and blocked an economically significant route to China.
Geotechnical properties and analysis
Initially, rockmass characterization and intact strength attribute were determined for the site to classify the failure zone. The parameters measured and obtained from the field and laboratory were integrated into the analytical models to obtain a conclusive interpretation of the failure mechanism. Structural, kinematic, and key block theory analyses have been carried out for decipher the evolution of the failure zone.
Results and discussion
Rock mass was found to be of fair quality, however, the structural instabilities and the presence of water has led to a progressive failure. Movement of the key block and subsequent sliding of wedges and foot failure appears to be a possible failure mechanism.
Conclusion
The present research explores the contributory engineering geological aspects of the Jure rock avalanche. The investigation results can be used to tackle similar large scale rock avalanches in similar geological terrains and thus minimizing the losses.
... Landslide dams that partially or entirely block rivers represent a very high hazard for the downstream fluvial reaches, especially in mountainous areas with deep, narrow valleys (e.g., Costa and Schuster 1988;Ermini and Casagli 2003;Hermanns et al. 2004;Korup and Tweed 2007;Evans et al. 2011;Fan et al. 2020). The failure of dams can produce destructive-type flash floods coupled with debris flows (Costa and Schuster 1988;Highland and Bobrowsky 2008;Perucca and Angillieri 2008;Zhou et al. 2013). ...
The design of engineering measures during emergency phases is crucial in mitigating the river flow impacts on landslide dams, avoiding dam breaks and related downstream flooding. Man-made hydraulic facilities represent a possible mitigation strategy for reducing the occurrence of dam breaching by diverting river inflow. Semi-empirical equations published in the literature may help define the landslide dam evolution and design the discharge to be diverted into the hydraulic works assuring the dam's stability. These approaches need to be carefully validated with case studies, an important step in evaluating the accuracy of predictive models. The work presents and discusses the pre-and post-seismic hydrologic conditions along the Nera River gorge focusing on the role of the pre-existing anthropic works in mitigating the impact of river discharge on the Sasso Pizzuto landslide dam triggered by the October 30, 2016 earthquake (Central Italy). Considering historical data, the upper part of the river catchment has experienced the highest discharge values during the landslide dam lifetime. The discriminant analysis approach of the hydro-geomorphometric characteristics supported the definition of the critical peak flow, avoiding the dam's instability. Thanks to an upstream hydropower bypass, about 80% of the river discharge increase have been diverted into an underground pipeline built in 1928 to feed the Preci hydroelectric plant (located a few kilometers downstream of the landslide dam). The discriminant analysis model, developed in the literature on other landslides worldwide , had a good performance in managing the upstream river discharge of Sasso Pizzuto dam, expanding its validity on other landslide dams.
... Landslide damming is a relatively common occurrence in mountain areas caused by sediments released from hillslopes that reaches valley floors and choke rivers (Costa and Schuster, 1988;Ermini and Casagli, 2003;Evans et al., 2011;Tacconi Stefanelli et al., 2016;Fan et al., 2017). On the one hand, landslide dam lakes pose serious threats to people and property due to upstream inundation and downstream flooding generated by breaching of such dams, initiation of other landslides, and debris flows (Chen et al., 2011;Evans et al., 2011;Peng and Zhang, 2012;Fan et al., 2017;Zhong et al., 2021). ...
... Landslide damming is a relatively common occurrence in mountain areas caused by sediments released from hillslopes that reaches valley floors and choke rivers (Costa and Schuster, 1988;Ermini and Casagli, 2003;Evans et al., 2011;Tacconi Stefanelli et al., 2016;Fan et al., 2017). On the one hand, landslide dam lakes pose serious threats to people and property due to upstream inundation and downstream flooding generated by breaching of such dams, initiation of other landslides, and debris flows (Chen et al., 2011;Evans et al., 2011;Peng and Zhang, 2012;Fan et al., 2017;Zhong et al., 2021). On the other hand, landslide dams represent huge archives for assessing the emplacement kinematics of the debris and for understanding their formation and evolution until the possible failure (Ermini and Casagli, 2003;Dufresne et al., 2010;Dufresne et al., 2016;Tacconi Stefanelli et al., 2016;Fan et al., 2017;Rouhi et al., 2019;Fan et al., 2020;Fan et al., 2021;Mei et al., 2021). ...
The giant prehistoric Seymareh landslide in the Zagros Mountains (Iran) is one of the largest known landslides on the Earth’s surface. The debris with an estimated volume of 44 km³ dammed two rivers, generating three lakes, that persisted for about 3 ka after the event. The post-overflow morphodynamics, characterized by an accelerated and intense stream network erosion, obliterated most of the primary landforms, such as ridges and blocks on the debris surface, making it difficult for scientists to interpret the emplacement kinematics of the landslide. In this regard, a novel spatial statistical approach is proposed here to zone the landslide debris in primary (original) and secondary (modified) regions which are, respectively, attributed to the original shape of the landslide debris and the one reshaped by fluvial erosion. The zonal computation combines the density classes of the mapped primary (ridge and blocks) and secondary (gullies) landforms, according to assumed conditions for representativeness of primary and secondary zones. For validating the model, 62 soil samples taken from the debris surface were classified according to the Unified Soil Classification System standard, and the field density measurements were performed in 28 sites. Based on the classification results, six types of soils were detected, among which 68% of them were ML. The ML samples were aggregated into five subgroups based on their relative proximity, and for each subgroup, four permeability tests were performed. The permeability results demonstrate that the high permeability values are associated with secondary zones, while low values with primary ones, thus confirming the zonation proposed by the statistical approach. The study of the spatial arrangement of the kinematic evidence on the primary landforms allowed to deduce that the landslide was a double-step single event, which infilled a paleo-valley enclosed by two anticline folds. During the emplacement, a part of the debris dissipated its energy over passing the anticlines with divergent directions, NW and NE, while the rest swept back into the Seymareh paleo-valley into the SE direction. The proposed approach represents a promising tool for the detection of primary landforms to assess the emplacement kinematics of landslides.
... Yan et al. [15] studied the feasibility of building dams with directional blasting in soil and water conservation projects. The feasibility of transforming a confined lake into a reservoir with blast-fill dams was investigated by Evans et al. [16]. Relationships between the index properties and strength parameters of blasted rockfill materials were developed [17]. ...
As a high-efficiency and low-investment method of dam construction, blast-fill dams have been widely used in water conservancy, mining engineering, soil and water conservation, disaster prevention and other projects. Through collecting data on the main projects of the blast-fill dams, the characteristics and development trends of blast-fill dams are analyzed in detail. Meanwhile, the design requirements of impervious bodies in the initial and reinforcement stages are systematically reviewed. Subsequently, with measured data of a typical blast-fill dam, the structural characteristics of blast-fill dams after blasting and the validity of the phreatic line height after reinforcement are analyzed using the discrete element method. We conclude that an appropriate construction schedule and flexible impervious material are critical features of the impervious body for a dam with large deformation. When the dam deformation is stable, a secondary treatment should be considered for the impervious body to improve the dam safety. The design ideas for the impervious body of blast-fill dams are also applicable to other dam types with large deformation for risk reduction, such as high rockfill dams, soft-rock dams and tailings dams, and have a certain significance for reference in the treatment of landslides and confined lakes.
... The flowrate of dam-breach floods can increase river flows to many times typical flood flows experienced in a river system and can even reach a rate much larger than the flowrates of recorded flash floods (Perucca and Angillieri 2009). The impacts of dam-breach flooding can extend to broad areas since the distances of dam-breach floods can vary from 1 to more than 1000 km (Geertsema 2008;Evans et al. 2011;Macias et al. 2004). The flood wave generated when the landslide debris enters the fluvial channel can have a significant impact, such as a water level tens of meters above the mean water level (Wang et al. 2004), or a large peak discharge flood wave (e.g., 5900 m 3 /s reported by Dunning et al. 2006). ...
... Most global LDam formation studies rely on descriptive analysis of case studies or quantitative relationships based on regional LDam studies or global landslide studies (Larsen et al. 2010;Tacconi Stefanelli et al. 2016. In previous LDam datasets, some of the geomorphological parameters of the landslides and blocked river valley came from empirical statistical relationships based on hydrological, geomorphological, or landslide studies (Evans et al. 2011), while others came from records or other accessible data sources (Tacconi Stefanelli et al. 2016Fan et al. 2020). ...
... In total, 779 LDam records were compiled from 34 countries/ regions. The locations of the records are clustered in the mountainous areas around the world, especially in the areas including European Alps (Tacconi Stefanelli et al. 2016), Rocky Mountains (Costa and Schuster 1988;Clague and Evans 1994), Andes Mountains Tacconi Stefanelli et al. 2018), Pamir Mountains (Storm 2010), Himalayas (Evans et al. 2011), the eastern edge of Tibet Plateau (Yin et al. 2009;Xu et al. 2009; (1) W = 9.68A 0.32 Fig. 2 Formation time trend of LDam event, inset shows the last 70 years in more detail Fan et al. 2012), and some mountainous areas on islands (Nash et al. 2008) (Fig. 1). In terms of spatial information of the new database, 85% of the records (666 out of 779 records) contain location information with a precision of approximately 0.01 degree (~ 1 km) and 583 records (~ 75%) have a precision better than or equal to 0.001 degree (~ 100 m) after geolocating processes. ...
To address the current data and understanding knowledge gap in landslide dam inventories related to geomorphological parameters, a new global-scale landslide dam dataset named River Augmented Global Landslide Dams (RAGLAD) was created. RAG-LAD is a collection of landslide dam records from multiple data sources published in various languages and many of these records we have been able to precisely geolocate. In total, 779 landslide dam records were compiled from 34 countries/regions. The spatial distribution , time trend, triggers, and geomorphological characteristic of the landslides and catchments where landslide dams formed are summarized. The relationships between geomorphological characteristics for landslides that form river dams are discussed and compared with those of landslides more generally. Additionally, a potential threshold for landslide dam formation is proposed, based on the relationship of landslide volume to river width. Our findings from our analysis of the value of the use of additional fluvial datasets to augment the database parameters indicate that they can be applied as a reliable supplemental data source, when the landslide dam records were accurately and precisely geolocated, although location precision in smaller river catchment areas can result in some uncertainty at this scale. This newly collected and supplemented dataset will allow the analysis and development of new relationships between landslides located near rivers and their actual propensity to block those particular rivers based on their geomorphology.
... In 1841, a flood from a rockslide-dammed lake on the Indus River to the northeast of Nanga Parbat, Pakistan, destroyed a Sikh Army camp at Attock more than 200 km downstream (Richardson & Reynolds, 2000). 1858, the breach of a land-slide across the Hunza valley caused a 9-meter rise in river level at Attock in less than 10 hours (Evans et al., 2011). Sarez Lake, in the Pamir Mountains of Tajikistan is currently attracting attention of the popular scientists (Ives, 2004). ...
... Involving local communities and their capacity building regarding glacier dynamics in watershed areas, those who frequently get more active in both handson preservation and restoration work and the decision-making process. By encouraging such participation, watershed management increases the possibility of success in management plans by fostering a feeling of community, assisting in the resolution of conflicts, and increasing commitment to meeting environmental goals (Evans et al., 2011). ...
... In addition, due to inaccessible terrain and lack of long-term monitoring activities, the Himalayan mountain system is poorly studied, as compared to other mountain systems in the world (Ruiz-Villanueva et al., 2017). All the above factors combined often trigger landslides along with the formation of landslide dam lakes, temporarily blocking the river valley (Degraff et al., 2010;Jakob et al., 2016;Evans et al., 2011). They are commonly formed in areas with steep slopes and narrow valleys where a little amount of sediment may cause blockage of the valley and formation of a lake (Nicoletti & Parise, 2002;Fan et al., 2012;Sharafi et al., 2019). ...
Detection and mapping of landslides is one of the most important techniques used for reducing the impact of natural disasters especially in the Himalaya, owing to its high amount of tectonic deformation, seismicity, and unfavorable climatic conditions. Moreover, the northeastern part of the Himalaya, severely affected by landslides every monsoon, is poorly studied. The information on the inventories is inhomogeneous and lacking. In this context, satellite-based earth observation data, which has significantly advanced in the last decade and often serves as a potential source for data collection, monitoring, and damage assessment for disasters in a short time span, has been implemented. Keeping in mind the above framework, this study aims to exploit the potentials of Sentinel-1 synthetic aperture radar (SAR) and Sentinel-2 optical imagery for identifying new landslides in vegetated and hilly areas of the northeastern part of India. In order to assess the potentials of our data and methodology, a landslide event which occurred on 13 August 2016 13:30 h (IST) in North Sikkim, India, triggered due to rainfall has been explored in detail. The landslide also resulted in the formation of a lake, 2.2 km in length and 290 m in width. Difficulty in procurement of cloud-free datasets immediately after the event led us to the use of Sentinel-1 SAR backscatter data, to assess its potential for this purpose. It is observed that the potential of SAR amplitude imagery is limited to different aspects as per the sensor look direction during the mode of acquisition. Furthermore, the present study also incorporates a change detection algorithm to evaluate the performance of the Sudden Landslide Identification Product (SLIP) model to identify new landslides using Sentinel-2 multispectral imagery. Overall, the results exhibit that integrated usage of both optical and SAR amplitude imagery may provide a plethora of information for identification and mapping of new landslides for damage assessment and early warning. All the above results combined together suggest this method for rapid identification of landslides in the Himalayan terrain with special emphasis on the northeastern part of the Himalaya. The automation of this method for future operational usage is also suggested.
... Cases with unknown causes occupied 4.7%. The most prominent forms of landslides leading to the formation of dams are rockslides, rock avalanches, and flows in unconsolidated sediments, which are primarily triggered by earthquakes and rainfall (Cruden and Varnes, 1996;Evans et al., 2011). Here the descriptions show how landslides of three types may evolve. ...
Landslide dams are common geological features in mountainous areas, which may have serious consequences due to sudden breaching of the dam. An effective emergency response requires rapid and accurate forecasts regarding the landslide dam breach process. However, most existing models use physical, mechanical, and erosion properties of the mean or characteristic grain sizes to represent the landslide deposits. The grain size distribution and variations in soil erodibility with the depth in the landslide dam are not considered, resulting in an incorrect estimation of the breach flow hydrograph. In this paper, a simplified landslide dam classification is presented based on the formation mechanism and grain size distribution of landslide dams. Additionally, the influences of grain size distribution on the residual dam height and breach process of landslide dams are analyzed. This paper proposes a numerical method to rapidly obtain the breach hydrographs and breach morphology evolution of landslide dams. The new method can quickly classify landslide dams according to geological survey data and predict the landslide dam breach process. Three types of representative landslide dams in China are simulated to validate the proposed method. The breach flow discharge is significantly affected by spillway excavation. This contribution can provide rapid prediction of the landslide dam breach process and can be used for the emergency response planning before dam breaching.
... Furthermore, landslide dams do not have channelized spillways or other protected outlets. Consequently, most landslide dams fail by overtopping (Costa and Schuster, 1988;Evans et al., 2011;Zhong et al., 2020a). Other failure modes are piping (Meyer et al., 1994;Korup, 2004;Shi et al., 2018) and sliding collapse of the downstream slope of the dam (Dunning et al., 2006). ...
Floods caused by breaches of embankment and landslide dams are not only a tremendous geological disaster, destroying people's lives and property, they also strongly shape the appearance of the landscape in the inundation area. This review addresses embankment and landslide dam breaches, with a particular focus on documented failure cases, laboratory and field experiments, as well as empirically and physically based models. The state of the art of physical and mathematical modeling technologies of underlying breach mechanisms and processes are also reviewed. First, the distribution, breach parameters, and failure modes of documented failure cases are analyzed. Second, based on physical model tests at different scales around the world, the breach processes of embankment and landslide dams caused by overtopping or piping/seepage are studied in depth. The breach characteristics for each type of dam are summarized. Third, typical empirically or physically based mathematical models are reviewed with a focus on artificially formed dams (i.e., earthfill, clay core rockfill, and concrete face rockfill dams) or naturally formed dams (i.e., landslide dams). Both uncertainties and limitations associated with formulations and calculating parameters of these mathematical models are also discussed. Finally, recommendations toward a better understanding of breach mechanisms and further development of mathematical models are proposed.
