The main reason for earthquake-induced landslides is liquefaction of soil,a process considered to occur mostly in sandy soils.Liquefaction which occurs in clayey soils has also been reported and proven in the recent l...The main reason for earthquake-induced landslides is liquefaction of soil,a process considered to occur mostly in sandy soils.Liquefaction which occurs in clayey soils has also been reported and proven in the recent liters- ture,but liquefaction in clayey soils still remains unclear and there are many questions that need to be addressed.In order to address these questions,an depth study on the liquefaction potential of clayey soils was conducted on the ba- sis of field investigation and a series of laboratory tests on the samples collected from the sliding surface of the land- slides.The liquefaction potential of the'soils was studied by means of undrained cyclic ring-shear tests.Research re- sults show that the liquefaction potential of sandy soils is higher than that of clayey soils given the same void ratio; the soil resistance to liquefaction rises with an increase in plasticity for clayey soils;relation between plasticity index and the liquefaction potential of soil can be used in practical application to estimate the liquefaction potential of展开更多
Landslide susceptibility mapping is a crucial tool for disaster prevention and management.The performance of conventional data-driven model is greatly influenced by the quality of the samples data.The random selection...Landslide susceptibility mapping is a crucial tool for disaster prevention and management.The performance of conventional data-driven model is greatly influenced by the quality of the samples data.The random selection of negative samples results in the lack of interpretability throughout the assessment process.To address this limitation and construct a high-quality negative samples database,this study introduces a physics-informed machine learning approach,combining the random forest model with Scoops 3D,to optimize the negative samples selection strategy and assess the landslide susceptibility of the study area.The Scoops 3D is employed to determine the factor of safety value leveraging Bishop’s simplified method.Instead of conventional random selection,negative samples are extracted from the areas with a high factor of safety value.Subsequently,the results of conventional random forest model and physics-informed data-driven model are analyzed and discussed,focusing on model performance and prediction uncertainty.In comparison to conventional methods,the physics-informed model,set with a safety area threshold of 3,demonstrates a noteworthy improvement in the mean AUC value by 36.7%,coupled with a reduced prediction uncertainty.It is evident that the determination of the safety area threshold exerts an impact on both prediction uncertainty and model performance.展开更多
Machine-learning methodologies have increasingly been embraced in landslide susceptibility assessment.However,the considerable time and financial burdens of landslide inventories often result in persistent data scarci...Machine-learning methodologies have increasingly been embraced in landslide susceptibility assessment.However,the considerable time and financial burdens of landslide inventories often result in persistent data scarcity,which frequently impedes the generation of accurate and informative landslide susceptibility maps.Addressing this challenge,this study compiled a nationwide dataset and developed a transfer learning-based model to evaluate landslide susceptibility in the Chongqing region specifically.Notably,the proposed model,calibrated with the warmup-cosine annealing(WCA)learning rate strategy,demonstrated remarkable predictive capabilities,particularly in scenarios marked by data limitations and when training data were normalized using parameters from the source region.This is evidenced by the area under the receiver operating characteristic curve(AUC)values,which exhibited significant improvements of 51.00%,24.40%and 2.15%,respectively,compared to a deep learning model,in contexts where only 1%,5%and 10%of data from the target region were used for retraining.Simultaneously,there were reductions in loss of 16.12%,27.61%and 15.44%,respectively,in these instances.展开更多
Landslide hazard mapping is a fundamental tool for disaster management activities in Loess terrains. Aiming at major issues with these landslide hazard assessment methods based on Naive Bayesian classification techniq...Landslide hazard mapping is a fundamental tool for disaster management activities in Loess terrains. Aiming at major issues with these landslide hazard assessment methods based on Naive Bayesian classification technique, which is difficult in quantifying those uncertain triggering factors, the main purpose of this work is to evaluate the predictive power of landslide spatial models based on uncertain Naive Bayesian classification method in Baota district of Yan＇an city in Shaanxi province, China. Firstly, thematic maps representing various factors that are related to landslide activity were generated. Secondly, by using field data and GIS techniques, a landslide hazard map was performed. To improve the accuracy of the resulting landslide hazard map, the strategies were designed, which quantified the uncertain triggering factor to design landslide spatial models based on uncertain Naive Bayesian classification method named NBU algorithm. The accuracies of the area under relative operating characteristics curves（AUC） in NBU and Naive Bayesian algorithm are 87.29% and 82.47% respectively. Thus, NBU algorithm can be used efficiently for landslide hazard analysis and might be widely used for the prediction of various spatial events based on uncertain classification technique.展开更多
An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China w...An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China were reviewed and the fimctions of drainage tunnel were categorized as catchment and interception. Numerical simulations were conducted. The results show that both catchment and interception tunnels have variation of the function in the simulation of monolayer model, which shows the reduction of permeability condition in lower layer. The function of catchment can be observed in the deep slope, while the function of interception is observed near groundwater source. By using the slope safety factor and discharge water amount as the objectives of optimal drainage tunnel location, and pore-water pressure in fixed node and section flux as the judgment for construction quality of adjacent drainage tunnel, the design principle of drainage tunnel was introduced. The K103 Landslide was illustrated as an example to determine the optimal drainage tunnel location. The measured drainage tunnel efficiency was evaluated and compared with that from the numerical analyses based on groundwater data. The results validate the present numerical study.展开更多
In worldwide, the most common triggering factor of rock landslides is extended and intense rainfall. However, different from the soil slope failure caused by softening action of infiltration rainwater, the mechanism o...In worldwide, the most common triggering factor of rock landslides is extended and intense rainfall. However, different from the soil slope failure caused by softening action of infiltration rainwater, the mechanism of rock landslide in rainfall is not clear. From the view of fracture mechanics, the propagation of cracks on rock slope and the development of sliding surface were researched. Then based on hydraulics formulas and using Sweden arc method, the influence of crack water on stability of rock slope was quantitatively studied. Finally, an example was given to check the theoretical approach. The result shows that the development of sliding surface of rock slope is mainly caused by crack propagation under hydrostatic pressure when the stress intensity factor KI at crack tip is bigger than the toughness index of rock fractures Klc, and the failure of slope is the result of hydraulic action of crack water and the softening of materials on sliding surface when the depth of crack water is bigger than a minimum value hmin.展开更多
The British Geological Survey(BGS)is the national geological agency for Great Britain and provides geoscientific information to government, other institutions and the general public.Landslide research at BGS is carrie...The British Geological Survey(BGS)is the national geological agency for Great Britain and provides geoscientific information to government, other institutions and the general public.Landslide research at BGS is carried out through a number of activities including surveying,database development and real-time monitoring of landslides.By underta-展开更多
There are 15 large areas in Moscow with development of deep landslides,on some of which the activation of landslides has taken place,sometimes directly concerned with human activity.The development of deep landslides ...There are 15 large areas in Moscow with development of deep landslides,on some of which the activation of landslides has taken place,sometimes directly concerned with human activity.The development of deep landslides on high banks of Moscow River results from deforming of Jurassic clays,which are deposited on depths of 20-110 m.They have complex mechanism,huge mass and provide big problems in realizing protective measures.In展开更多
The Wenchuan earthquake of 2008 in the Sichuan Province(China)is one of the most destructive earthquakes in recent years.It killed about 89 thousand people and caused considerable economic damage.In the first phase of...The Wenchuan earthquake of 2008 in the Sichuan Province(China)is one of the most destructive earthquakes in recent years.It killed about 89 thousand people and caused considerable economic damage.In the first phase of research the main objective was in detailed image interpretation and mapping of the territory of a key site around Beichuan City,at the initial stage of adaptation of the natural-technical environment after the catastrophic earthquake.For this purpose we used展开更多
Landslide dams and lakes can cause great casualties and economic losses.A landslide dammed lake named Tangjiashan by Wenchuan earthquake in China was well known all over the world since May 12,2008. Many other landsli...Landslide dams and lakes can cause great casualties and economic losses.A landslide dammed lake named Tangjiashan by Wenchuan earthquake in China was well known all over the world since May 12,2008. Many other landslide dams or lakes can also formed by rainfall or water fluctuation besides earthquake. Landslides along the river or branch banks in the Three Gorges Reservoir area face dam or lake forming possibility especially within the water展开更多
Landslides continue to be a major natural disaster causing loss of life,extensive human suffering and economic losses,despite advances in understanding of mechanisms,monitoring and mitigation technologies related to l...Landslides continue to be a major natural disaster causing loss of life,extensive human suffering and economic losses,despite advances in understanding of mechanisms,monitoring and mitigation technologies related to landslides.However,landslides characteristics differ according to climatic,geological展开更多
Landslide is one of the most frequently occurring natural hazards in Manipur which is a tectonically active area.Rainfall-induced landslides are studied along NH-39 to find out the impact of rainfall.Though rainfall-i...Landslide is one of the most frequently occurring natural hazards in Manipur which is a tectonically active area.Rainfall-induced landslides are studied along NH-39 to find out the impact of rainfall.Though rainfall-induced landslides are usually shallow slips in nature and the volume of slip mass is not very large, the damage caused to the properties and infrastructures can be quite serious due to their highly frequent occurrences.NH-39,which is one of the life lines of Manipur,is regularly affected by frequent landslides during rainy season and the frequency is increasing at present as compared to the recent past.Several lands-展开更多
The fluctuation of ground water table of landslide caused by the changing of rain fall and reservoir water level leads the slip zone to possess the complicated deformation features of stepped and vibration.Actual role...The fluctuation of ground water table of landslide caused by the changing of rain fall and reservoir water level leads the slip zone to possess the complicated deformation features of stepped and vibration.Actual role of the ground water fluctuation to landslide is the synthesis of pore pressure,chemical intenerating展开更多
In its upper and middle course, the Kali Gandaki river in Western Nepal flows across the Himalayan ranges more or less following tectonic lineaments (NNE—SSW). In this paper we focus our attention on certain slope de...In its upper and middle course, the Kali Gandaki river in Western Nepal flows across the Himalayan ranges more or less following tectonic lineaments (NNE—SSW). In this paper we focus our attention on certain slope deformations along the valley flanks of the middle course, especially on very narrow sections of this large transverse valley. Although the valley experienced several Pleistocene periods of strong glaciations and the powerful river flowing through it currently ranks as the second largest in Nepal we find a number of those amazing valley constrictions in the studied area which should not be ascribed to differences in rock resistance against erosion or to active tectonic control. It can best be explained by deep\|seated rock creep (Chigira,1992), a process which is frequently connected with landslides or rockfalls and must have developed during late Pleistocene and Holocene, i.e. since the valley was deglaciated. In order to prove this thesis we shall describe the situation by means of three case studies between the villages of Rukse (upstream) and Beni (downstream). Another fourth example of gravitational slope deformation described in this paper is located downstream of the reach of previous valley glaciations. Here, too, deep\|seated rock creep is considered to be responsible for the observed mass movements and thus for slope deformation.展开更多
Landslide danger is well known and improved prediction can save lives and property.To predict the landslide danger for every geological structure the government and geological organizations use geoindicators which mon...Landslide danger is well known and improved prediction can save lives and property.To predict the landslide danger for every geological structure the government and geological organizations use geoindicators which monitor the sites and warn the scientist that"in Baybaksay there is a dangerous situation"or"Earth movement occurred 124 km southwest by the Tashkent-Charvak road".All this is done with the help of geological indicators and some factors for the current geological Earth structure.展开更多
Landslide is one of the common natural hazards occurring in Sri Lanka.This is more signifycant in central highlands of the country.Some natural conditions of central highlands like geology and geomorphological feature...Landslide is one of the common natural hazards occurring in Sri Lanka.This is more signifycant in central highlands of the country.Some natural conditions of central highlands like geology and geomorphological features,steep slopes,getting high intensity of rainfall,etc.are direct influences on occurrence of high number of landslides compared to other regions of Sri Lanka.However,some human activities like deforestation,chena cultivation,improper constructions in hill slopes,etc.also contribute to accelerating landslide process in the study area. According to statistic data of past landslides of this region,those events destroyed valuable agricultural lands,houses and properties,etc.as well as lost展开更多
The summer resort of Murree and adjoining areas is characterized by high degree of erosivity and erodibility due to both natural and man induced factors. This area is part of a young orogenic belt that is experiencing...The summer resort of Murree and adjoining areas is characterized by high degree of erosivity and erodibility due to both natural and man induced factors. This area is part of a young orogenic belt that is experiencing one of the world’s most rapid uplift rates, and is located in near vicinity of major thrust faults. Shear zones associated with still active faults, such as Murree Thrust and also the folding generated due to thrusting induce an inherited weakness and natural instability potential in the rocks of the Murree Hills. Ever increasing population pressure, deforestation, large\|scale construction works including a new township and a road network have further aggravated the problem. In order to study the landslides and other mass movement related problems in Murree, an area around the main town is selected for detailed analysis of the problem as it has been focus of major development and road construction work. This study is an attempt to prepare a preliminary hazard/landslide map along major road network, around Murree town to identify the unstable areas. Data collection during the fieldwork and its analysis were carried out on Geographic Information System (GIS) based on ILWIS format of the ITC, the Netherlands. Detailed study of a few selected landslides has also been conducted to understand the mechanism of failure and extent of damage.展开更多
I want to know God’s thoughts.The rest are details. Albert Einstein The first reference to landslides deeply goes long far for ages.For centuries mankind try to solve the secret of landslides and get answers to quest...I want to know God’s thoughts.The rest are details. Albert Einstein The first reference to landslides deeply goes long far for ages.For centuries mankind try to solve the secret of landslides and get answers to questions:Where?When?How?Where could the nature have hidden the keys to landslide secret? Perhaps the latest achievements of science and technology could bring us closer to the clues of展开更多
Damming landslides are very common in China, they ever blocked the rivers and streams completely or partly, and form natural lakes. Now more than 150 damming landslides in China are recognized through field investigat...Damming landslides are very common in China, they ever blocked the rivers and streams completely or partly, and form natural lakes. Now more than 150 damming landslides in China are recognized through field investigation and data collection indoors. These Landslides distribute in steep mountainous counties around the Qinghai—Tibet Plateau, and mainly of which in southwest China and northwest China.. Studies show that the distribution of damming landslides has a close relation with the event of the Tibet plateau upheaval. The thermodynamic effect on the free atmosphere results from rapid upheaval of Qinghai\|Tibet plateau is more and more intensive, it causes air to circulate from east to west. In winter, the high Tibet Plateau leads the cool air gather quickly and high cool potential to be stronger. On one side, an anticyclone cool high pressure forms near the ground surface at the altitude of 4000～5000m, and produces winter monsoon wind. On the other side, the shielding effect of the plateau impedes the air from Siberia touching with the air from south Indian Ocean, which causes the cool air from Siberia enters China frequently and strengthens the cool and drought in northwest China. In summer, the monsoon wind is impeded by the plateau and cannot enter into north China, where it is dry, it can only moves around the plateau and at the edge enters into southwest, south, middle and east China, where the rainfall process is strong. Thus south and east of the plateau become the areas with many damming landslides resulted from heavy rain.展开更多
Recently,Artificial Neural Networks(ANNs)have been used for various scientific and engineering applications essentially because they allow the modeling of a process,which starts from the database containing the variab...Recently,Artificial Neural Networks(ANNs)have been used for various scientific and engineering applications essentially because they allow the modeling of a process,which starts from the database containing the variables that describe that particular process.They have already been applied to the study of landslides in particular,with reference to the indirect determination of the triggering展开更多
文摘The main reason for earthquake-induced landslides is liquefaction of soil,a process considered to occur mostly in sandy soils.Liquefaction which occurs in clayey soils has also been reported and proven in the recent liters- ture,but liquefaction in clayey soils still remains unclear and there are many questions that need to be addressed.In order to address these questions,an depth study on the liquefaction potential of clayey soils was conducted on the ba- sis of field investigation and a series of laboratory tests on the samples collected from the sliding surface of the land- slides.The liquefaction potential of the'soils was studied by means of undrained cyclic ring-shear tests.Research re- sults show that the liquefaction potential of sandy soils is higher than that of clayey soils given the same void ratio; the soil resistance to liquefaction rises with an increase in plasticity for clayey soils;relation between plasticity index and the liquefaction potential of soil can be used in practical application to estimate the liquefaction potential of
基金Project(G2022165004L)supported by the High-end Foreign Expert Introduction Program,ChinaProject(2021XM3008)supported by the Special Foundation of Postdoctoral Support Program,Chongqing,China+1 种基金Project(2018-ZL-01)supported by the Sichuan Transportation Science and Technology Project,ChinaProject(HZ2021001)supported by the Chongqing Municipal Education Commission,China。
文摘Landslide susceptibility mapping is a crucial tool for disaster prevention and management.The performance of conventional data-driven model is greatly influenced by the quality of the samples data.The random selection of negative samples results in the lack of interpretability throughout the assessment process.To address this limitation and construct a high-quality negative samples database,this study introduces a physics-informed machine learning approach,combining the random forest model with Scoops 3D,to optimize the negative samples selection strategy and assess the landslide susceptibility of the study area.The Scoops 3D is employed to determine the factor of safety value leveraging Bishop’s simplified method.Instead of conventional random selection,negative samples are extracted from the areas with a high factor of safety value.Subsequently,the results of conventional random forest model and physics-informed data-driven model are analyzed and discussed,focusing on model performance and prediction uncertainty.In comparison to conventional methods,the physics-informed model,set with a safety area threshold of 3,demonstrates a noteworthy improvement in the mean AUC value by 36.7%,coupled with a reduced prediction uncertainty.It is evident that the determination of the safety area threshold exerts an impact on both prediction uncertainty and model performance.
基金Project(2301DH09002)supported by the Bureau of Planning and Natural Resources,Chongqing,ChinaProject(2022T3051)supported by the Science and Technology Service Network Initiative,ChinaProject(2018-ZL-01)supported by the Sichuan Transportation Science and Technology,China。
文摘Machine-learning methodologies have increasingly been embraced in landslide susceptibility assessment.However,the considerable time and financial burdens of landslide inventories often result in persistent data scarcity,which frequently impedes the generation of accurate and informative landslide susceptibility maps.Addressing this challenge,this study compiled a nationwide dataset and developed a transfer learning-based model to evaluate landslide susceptibility in the Chongqing region specifically.Notably,the proposed model,calibrated with the warmup-cosine annealing(WCA)learning rate strategy,demonstrated remarkable predictive capabilities,particularly in scenarios marked by data limitations and when training data were normalized using parameters from the source region.This is evidenced by the area under the receiver operating characteristic curve(AUC)values,which exhibited significant improvements of 51.00%,24.40%and 2.15%,respectively,compared to a deep learning model,in contexts where only 1%,5%and 10%of data from the target region were used for retraining.Simultaneously,there were reductions in loss of 16.12%,27.61%and 15.44%,respectively,in these instances.
基金Projects(41362015,51164012) supported by the National Natural Science Foundation of ChinaProject(2012AA061901) supported by the National High-tech Research and Development Program of China
文摘Landslide hazard mapping is a fundamental tool for disaster management activities in Loess terrains. Aiming at major issues with these landslide hazard assessment methods based on Naive Bayesian classification technique, which is difficult in quantifying those uncertain triggering factors, the main purpose of this work is to evaluate the predictive power of landslide spatial models based on uncertain Naive Bayesian classification method in Baota district of Yan＇an city in Shaanxi province, China. Firstly, thematic maps representing various factors that are related to landslide activity were generated. Secondly, by using field data and GIS techniques, a landslide hazard map was performed. To improve the accuracy of the resulting landslide hazard map, the strategies were designed, which quantified the uncertain triggering factor to design landslide spatial models based on uncertain Naive Bayesian classification method named NBU algorithm. The accuracies of the area under relative operating characteristics curves（AUC） in NBU and Naive Bayesian algorithm are 87.29% and 82.47% respectively. Thus, NBU algorithm can be used efficiently for landslide hazard analysis and might be widely used for the prediction of various spatial events based on uncertain classification technique.
基金Foundation item： Project（1220BAK10B06） supported by the National ＂Twelfth Five-Year＂ Plan for Science ＆ Technology Support Program of China Project（20100101110026） supported by the PhD Programs Foundation of Ministry of Education of China Project（2009RS0050） supported by the Key Innovation Team Support Fund of Zhejiang Province, China
文摘An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China were reviewed and the fimctions of drainage tunnel were categorized as catchment and interception. Numerical simulations were conducted. The results show that both catchment and interception tunnels have variation of the function in the simulation of monolayer model, which shows the reduction of permeability condition in lower layer. The function of catchment can be observed in the deep slope, while the function of interception is observed near groundwater source. By using the slope safety factor and discharge water amount as the objectives of optimal drainage tunnel location, and pore-water pressure in fixed node and section flux as the judgment for construction quality of adjacent drainage tunnel, the design principle of drainage tunnel was introduced. The K103 Landslide was illustrated as an example to determine the optimal drainage tunnel location. The measured drainage tunnel efficiency was evaluated and compared with that from the numerical analyses based on groundwater data. The results validate the present numerical study.
基金Project(2008CB425802) supported by the National Basic Research Program of China Project(40872181) supported by the National Natural Science Foundation of ChinaProject(09R2200200) supported by the West Light Foundation of Chinese Academy of Sciences
文摘In worldwide, the most common triggering factor of rock landslides is extended and intense rainfall. However, different from the soil slope failure caused by softening action of infiltration rainwater, the mechanism of rock landslide in rainfall is not clear. From the view of fracture mechanics, the propagation of cracks on rock slope and the development of sliding surface were researched. Then based on hydraulics formulas and using Sweden arc method, the influence of crack water on stability of rock slope was quantitatively studied. Finally, an example was given to check the theoretical approach. The result shows that the development of sliding surface of rock slope is mainly caused by crack propagation under hydrostatic pressure when the stress intensity factor KI at crack tip is bigger than the toughness index of rock fractures Klc, and the failure of slope is the result of hydraulic action of crack water and the softening of materials on sliding surface when the depth of crack water is bigger than a minimum value hmin.
文摘The British Geological Survey(BGS)is the national geological agency for Great Britain and provides geoscientific information to government, other institutions and the general public.Landslide research at BGS is carried out through a number of activities including surveying,database development and real-time monitoring of landslides.By underta-
文摘There are 15 large areas in Moscow with development of deep landslides,on some of which the activation of landslides has taken place,sometimes directly concerned with human activity.The development of deep landslides on high banks of Moscow River results from deforming of Jurassic clays,which are deposited on depths of 20-110 m.They have complex mechanism,huge mass and provide big problems in realizing protective measures.In
文摘The Wenchuan earthquake of 2008 in the Sichuan Province(China)is one of the most destructive earthquakes in recent years.It killed about 89 thousand people and caused considerable economic damage.In the first phase of research the main objective was in detailed image interpretation and mapping of the territory of a key site around Beichuan City,at the initial stage of adaptation of the natural-technical environment after the catastrophic earthquake.For this purpose we used
文摘Landslide dams and lakes can cause great casualties and economic losses.A landslide dammed lake named Tangjiashan by Wenchuan earthquake in China was well known all over the world since May 12,2008. Many other landslide dams or lakes can also formed by rainfall or water fluctuation besides earthquake. Landslides along the river or branch banks in the Three Gorges Reservoir area face dam or lake forming possibility especially within the water
文摘Landslides continue to be a major natural disaster causing loss of life,extensive human suffering and economic losses,despite advances in understanding of mechanisms,monitoring and mitigation technologies related to landslides.However,landslides characteristics differ according to climatic,geological
文摘Landslide is one of the most frequently occurring natural hazards in Manipur which is a tectonically active area.Rainfall-induced landslides are studied along NH-39 to find out the impact of rainfall.Though rainfall-induced landslides are usually shallow slips in nature and the volume of slip mass is not very large, the damage caused to the properties and infrastructures can be quite serious due to their highly frequent occurrences.NH-39,which is one of the life lines of Manipur,is regularly affected by frequent landslides during rainy season and the frequency is increasing at present as compared to the recent past.Several lands-
文摘The fluctuation of ground water table of landslide caused by the changing of rain fall and reservoir water level leads the slip zone to possess the complicated deformation features of stepped and vibration.Actual role of the ground water fluctuation to landslide is the synthesis of pore pressure,chemical intenerating
文摘In its upper and middle course, the Kali Gandaki river in Western Nepal flows across the Himalayan ranges more or less following tectonic lineaments (NNE—SSW). In this paper we focus our attention on certain slope deformations along the valley flanks of the middle course, especially on very narrow sections of this large transverse valley. Although the valley experienced several Pleistocene periods of strong glaciations and the powerful river flowing through it currently ranks as the second largest in Nepal we find a number of those amazing valley constrictions in the studied area which should not be ascribed to differences in rock resistance against erosion or to active tectonic control. It can best be explained by deep\|seated rock creep (Chigira,1992), a process which is frequently connected with landslides or rockfalls and must have developed during late Pleistocene and Holocene, i.e. since the valley was deglaciated. In order to prove this thesis we shall describe the situation by means of three case studies between the villages of Rukse (upstream) and Beni (downstream). Another fourth example of gravitational slope deformation described in this paper is located downstream of the reach of previous valley glaciations. Here, too, deep\|seated rock creep is considered to be responsible for the observed mass movements and thus for slope deformation.
文摘Landslide danger is well known and improved prediction can save lives and property.To predict the landslide danger for every geological structure the government and geological organizations use geoindicators which monitor the sites and warn the scientist that"in Baybaksay there is a dangerous situation"or"Earth movement occurred 124 km southwest by the Tashkent-Charvak road".All this is done with the help of geological indicators and some factors for the current geological Earth structure.
文摘Landslide is one of the common natural hazards occurring in Sri Lanka.This is more signifycant in central highlands of the country.Some natural conditions of central highlands like geology and geomorphological features,steep slopes,getting high intensity of rainfall,etc.are direct influences on occurrence of high number of landslides compared to other regions of Sri Lanka.However,some human activities like deforestation,chena cultivation,improper constructions in hill slopes,etc.also contribute to accelerating landslide process in the study area. According to statistic data of past landslides of this region,those events destroyed valuable agricultural lands,houses and properties,etc.as well as lost
文摘The summer resort of Murree and adjoining areas is characterized by high degree of erosivity and erodibility due to both natural and man induced factors. This area is part of a young orogenic belt that is experiencing one of the world’s most rapid uplift rates, and is located in near vicinity of major thrust faults. Shear zones associated with still active faults, such as Murree Thrust and also the folding generated due to thrusting induce an inherited weakness and natural instability potential in the rocks of the Murree Hills. Ever increasing population pressure, deforestation, large\|scale construction works including a new township and a road network have further aggravated the problem. In order to study the landslides and other mass movement related problems in Murree, an area around the main town is selected for detailed analysis of the problem as it has been focus of major development and road construction work. This study is an attempt to prepare a preliminary hazard/landslide map along major road network, around Murree town to identify the unstable areas. Data collection during the fieldwork and its analysis were carried out on Geographic Information System (GIS) based on ILWIS format of the ITC, the Netherlands. Detailed study of a few selected landslides has also been conducted to understand the mechanism of failure and extent of damage.
文摘I want to know God’s thoughts.The rest are details. Albert Einstein The first reference to landslides deeply goes long far for ages.For centuries mankind try to solve the secret of landslides and get answers to questions:Where?When?How?Where could the nature have hidden the keys to landslide secret? Perhaps the latest achievements of science and technology could bring us closer to the clues of
文摘Damming landslides are very common in China, they ever blocked the rivers and streams completely or partly, and form natural lakes. Now more than 150 damming landslides in China are recognized through field investigation and data collection indoors. These Landslides distribute in steep mountainous counties around the Qinghai—Tibet Plateau, and mainly of which in southwest China and northwest China.. Studies show that the distribution of damming landslides has a close relation with the event of the Tibet plateau upheaval. The thermodynamic effect on the free atmosphere results from rapid upheaval of Qinghai\|Tibet plateau is more and more intensive, it causes air to circulate from east to west. In winter, the high Tibet Plateau leads the cool air gather quickly and high cool potential to be stronger. On one side, an anticyclone cool high pressure forms near the ground surface at the altitude of 4000～5000m, and produces winter monsoon wind. On the other side, the shielding effect of the plateau impedes the air from Siberia touching with the air from south Indian Ocean, which causes the cool air from Siberia enters China frequently and strengthens the cool and drought in northwest China. In summer, the monsoon wind is impeded by the plateau and cannot enter into north China, where it is dry, it can only moves around the plateau and at the edge enters into southwest, south, middle and east China, where the rainfall process is strong. Thus south and east of the plateau become the areas with many damming landslides resulted from heavy rain.
文摘Recently,Artificial Neural Networks(ANNs)have been used for various scientific and engineering applications essentially because they allow the modeling of a process,which starts from the database containing the variables that describe that particular process.They have already been applied to the study of landslides in particular,with reference to the indirect determination of the triggering
