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This study presents an integrated framework that combines spatial clustering techniques and multi-source geospatial data to comprehensively assess and understand geological hazards in Hunan Province, China. The research integrates self-organizing map (SOM) and geo-self-organizing map (Geo-SOM) to explore the relationships between environmental factors and the occurrence of various geological hazards, including landslides, slope failures, collapses, ground subsidence, and debris flows. The key findings reveal that annual average precipitation (Pre), profile curvature (Pro_cur), and slope (Slo) are the primary factors influencing the composite geological hazard index (GI) across the province. Importantly, the relationships between these key factors and GI exhibit spatial variability, as evidenced by the random intercept and slope models, highlighting the need for customized mitigation strategies. Additionally, the study demonstrates that land use patterns and stratigraphic stratum lithology significantly impact the cluster-specific relationships between the key factors and GI, emphasizing the importance of natural resource management for effective geological hazard mitigation. The proposed integrated framework provides valuable insights for policymakers and resource managers to develop spatially-aware strategies for geological hazard risk reduction and climate change adaptation. [ABSTRACT FROM AUTHOR]

Interferometry Synthetic Aperture Radar (InSAR) technology is widely employed in the identification of geological hazards. However, in regions characterized by high mountains, canyons, and dense vegetation, decorrelation often hampers effective identification. In this study, focusing on the landslide-prone area of Wenxian County in Longnan City with abundant vegetation, we propose a Multi-Temporal InSAR (MTI) monitoring method that integrates Persistent Scatterers (PS) points with Slowly-Decorrelating Filtered Phase (SDFP) points in order to effectively reduce decorrelation effects. Additionally, we conduct high-precision monitoring of landslide surface deformation in Wenxian County using the the Generic Atmospheric Correction Online Service for InSAR (GACOS). Based on cross-validation of results obtained from three different techniques and the comparison with GNSS monitoring results, we validate the accuracy of these identification results. Furthermore, we use time-series deformation analysis methods to analyze the dynamic evolution of the characteristics of landslides in Chengguan Town and Koutouba Township, Wenxian County, Longnan City, and investigate their relationship with different environmental factors, such as rainfall and temperature. Our findings demonstrate that the spatial distribution consistency of the surface deformation information identified by the three techniques is high. However, StaMPS-MTI technology has the highest spatial sampling rate in deformation results, which is 21.02% higher than that of StaMPS-PS and over 4.6 times higher than that of StaMPS-SBAS. Additionally, the errors and Root Mean Square Error (RMSE) of StaMPS-MTI results in comparison to GNSS monitoring results are also the smallest, with values of 5.35 mm and 9.38 mm. We also observe varying degrees of deformation in Level 1 landslide areas identified by the STAMPS-MTI method in Chengguan Town and Koutouba Township with distinct seasonal characteristics. The cumulative deformation in the period from March to June shows a noticeable acceleration, with landslide incidents caused by the freeze-thaw phenomenon due to rising temperatures in March and April while rainfall caused landslide incidents from April to June. This research provides essential data and scientific support for geological hazard monitoring, prevention, and early warning. [ABSTRACT FROM AUTHOR]

Liangshan Prefecture, located at the northeastern edge of the Hengduan Mountain System and within the southern section of the Sichuan-Yunnan tectonic belt in Sichuan Province, China, a region prone to landslides, collapses and debris flows due to its active tectonics, complex topography and significant river erosion. By analysing a dataset of environment factors and geological hazard catalogue, the research uses the Relief algorithm to identify critical influencing factors for each hazard type, selecting 10, 9 and 9 factors for landslides, collapses and debris flows, respectively. Five models are used to assess the vulnerability of these hazards: the Information Value model, the Evidence Weight model, the Logistic Regression model, and both the Evidence Weight-Logistic Regression and the Information Value-Logistic Regression coupled models. The effectiveness of these models is confirmed by confusion matrix and ROC curve analyses, with the combined models showing particularly high accuracy in assessing susceptibility. High risk zones were identified in specific areas and along major fault zones in Liangshan Prefecture. The research provides significant insights into the susceptibility of geological hazards in mountainous and canyon regions, offering a comprehensive approach that goes beyond the limitations of single model applications. This methodology not only provides more accurate and comprehensive results, but also serves as a fundamental reference for geological hazard mitigation and management in Liangshan Prefecture, potentially benefiting similar regions worldwide. [ABSTRACT FROM AUTHOR]

In order to scientifically and rationally evaluate the susceptibility to landslide hazards in Tekes County, Yili State. This paper takes Tekes County in Xinjiang as an example, on the basis of a comprehensive analysis of the regional geological environment conditions and the distribution pattern and formation conditions of geological disasters, using the data of geological disaster points (landslide center points), and through the correlation matrix calculation of the evaluation factors, the nine evaluation factors with larger absolute values of correlation coefficients were determined to construct the evaluation system of the susceptibility to landslide geological hazards in Tekesi County. Combining the information quantity method and the entropy value method, using the weights determined by the entropy value method, the information quantity method is used to calculate the information quantity value of each factor within the factor, calculate the susceptibility index of landslide geological disasters within the territory of Tekes County, and then carry out the landslide susceptibility evaluation. The susceptibility of landslide disasters was evaluated by ArcGIS. The results show that the landslide disaster susceptibility level in Tekes County can be divided into four levels: high susceptibility, medium susceptibility, low susceptibility, and not susceptible, with areas of 491.3276 km2, 1181.5171 km2, 1674.7609 km2 and 5295.2976 km2 accounting for 5.68%, 13.67%, 19.38% and 61.27% of the total area of Tex County, respectively. The AUC number obtained by the success curve method (ROC) is 0.8736, reflecting the evaluation accuracy of 87.36%, indicating that the model method used in this paper is effective. The results are expected to provide practical data support for landslide disaster control in Tekes County and provide a reference for geological disaster monitoring, early warning and engineering prevention and control deployment in Yili Valley. [ABSTRACT FROM AUTHOR]

The geological structure of the reservoir bank landslide is complex and intricate. After deformation and damage, it causes river blockage, surges, and loss of people's lives and property, posing a huge threat. At present, in academia and engineering applications, a large number of techniques such as inclinometers, rain gauges, and surface GNSS deformation monitoring are still used for monitoring landslides on reservoir banks. This type of monitoring method has the problem of "point to surface" which can easily lead to missed detection and reporting in some areas, some disaster points are close to water and steep, difficult to reach, and equipment installation is difficult. This work designs and implements a non-contact video quantitative monitoring system for surface deformation of geological disaster. By constructing a deep learning neural network, deformation area recognition and displacement quantitative calculation are achieved; By obtaining continuous images for a long time, draw the surface displacement-time curve, and output the surface deformation data and landform changes of the disaster. Meanwhile, this work explores the impact of different lighting conditions on the recognition results of target areas. This work can provide non-contact monitoring methods and dynamic warning support for large-scale monitoring of geological disasters. [ABSTRACT FROM AUTHOR]

Landslide geological disasters, occurring globally, often result in significant loss of life and extensive economic damage. In recent years, the severity of these disasters has increased, likely due to the frequent occurrence of extreme rainstorms associated with global warming. This escalating trend emphasizes the urgent need for a simple and efficient method to identify hidden dangers related to landslide geological disasters. Areas experiencing seasonal heavy rainfall are particularly susceptible to such disasters, posing a serious threat to the lives and property of local residents. In response to the challenging characteristics of landslide geological hazards, such as their strong concealment and the high vegetation coverage in the Liupan Mountain area of the Loess Plateau, this study focuses on the integrated remote sensing identification and research of hidden landslide dangers in Longde County. The methodology combines differential interferometric synthetic aperture radar technology (D-InSAR) and high-resolution optical remote sensing. Surface deformation information of Longde County was obtained by analyzing 85 Sentinel-1A data from 2019 to mid-2020 using Stacking-InSAR, in conjunction with high-resolution optical remote sensing image data from GF-2 in 2019. Furthermore, the study conducted integrated remote sensing identification and field verification of landslide hazards throughout the entire county. This involved interpreting the shape and deformation marks of landslide hazards, identifying the disaster-bearing bodies, and expertly interpreting the environmental factors contributing to the hazards. As a result, 47 suspected landslide hazards and 21 field investigation points were identified, with 16 hazards verified with an accuracy of 76.19%. This outcome directly confirms the applicability and accuracy of the integrated remote sensing identification technology in the study area. The research results presented in this paper provide an effective scientific and theoretical basis for the monitoring and treatment of landslide geological disasters in the future stages. They also play a pivotal role in the prevention of such disasters. [ABSTRACT FROM AUTHOR]

The marine economy and submarine landslides represent two critical and seemingly disparate areas of concern within oceanic studies. The marine economy encompasses industries and activities such as fishing, shipping, and tourism that rely on the health and accessibility of marine environments. In contrast, submarine landslides, which are significant geological hazards, can impact marine infrastructure, disrupt economic activities, and pose risks to coastal communities. This article explores the balance between advancing marine economic interests and mitigating the risks associated with submarine landslides. It examines current research, technological advancements, and policy measures aimed at addressing these challenges. Strategies for enhancing economic sustainability while safeguarding against geological hazards are discussed, emphasizing the need for integrated approaches that consider both economic and environmental factors. [ABSTRACT FROM AUTHOR]

Geological disasters refer to adverse geological phenomena that occur under the influence of natural or human factors and cause damage to human life and property. Establishing prevention and control zones based on geological disaster risk assessment results in land planning and management is crucial for ensuring safe regional development. In recent years, there has been an increase in extreme rainfall events, so it is necessary to conduct effective geological hazard and risk assessments for different extreme rainfall conditions. Based on the first national geological disaster risk survey results, this paper uses the analytic hierarchy process (AHP) combined with the information method (IM) to construct four extreme rainfall conditions, namely, 10-year, 20-year, 50-year, and 100-year return periods. The susceptibility, hazard, vulnerability, and risk of geological disasters in the Laoshan District in eastern China are evaluated, and prevention and control zones are established based on the evaluation results. The results show that: (1) There are 121 collapse geological disasters in Laoshan District, generally at a low susceptibility level. (2) A positive correlation exists between extreme rainfall and hazards/risks. With the rainfall condition changing from a 10-year return period to a 100-year return period, the proportion of high-hazard zones increased from 20% to 41%, and high-risk zones increased from 31% to 51%, respectively. The Receiver operating characteristic (ROC) proved that the assessment accuracy was acceptable. (3) Key, sub-key, and general prevention zones have been established, and corresponding prevention and control suggestions have been proposed, providing a reference for geological disaster prevention and early warning in other regions. [ABSTRACT FROM AUTHOR]

This research studied the risk assessment of geological hazards, such as landslides and debris flow, under the time series and trend characteristics of extreme precipitation events in the last 60 years in nine typical regions of the lower Jinshajiang River Basin. Nine indicators, including slope, engineering geological rock group, slope structure type, distance to road, topographic relief, distance to fault, distance to the water system, vegetation cover and profile curvature, were selected as the index factors for landslide susceptibility evaluation, and the information quantity method was used to obtain the landslide susceptibility evaluation of the study area. Based on the susceptibility evaluation, the spatial analysis function of GIS was used to derive the geological hazard zoning under the extreme rainfall trend. The results showed that the areas with high extreme rainfall trends have higher densities of geological hazard development and they are concentrated, while areas with low extreme rainfall trends have relatively less geological hazard development, and what development exists is scattered. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mitigation of geological hazards through science and engineering applications is one of the most effective ways to reduce their impact on human life and local infrastructure. It involves precise mapping of hazards, assessment of their potential, monitoring, early warning, geotechnical treatment, design of vital infrastructural facilities and creating awareness at local levels. Several such initiatives have been taken at government level to deal with the earthquakes and landslides in the eastern Himalayan region. These efforts facilitated identification of potential areas and sites, susceptible to future events and helped in improving our understanding of crustal structure, geodynamics, tectonics, seismogenesis, and soil properties, etc. The paper highlights details of the major initiatives, significant achievements, and priorities to help in better mitigation of earthquake and landslide hazards in the eastern Himalayan region. [ABSTRACT FROM AUTHOR]

Faults contribute significantly to the formation and distribution of landslides, especially in the highly faulted Qinling-Daba mountain region. Yet, evidence of the long-term and regional dependency influence of active faults on landslides is limited. In particular, in-depth knowledge is still lacking regarding their specific mechanisms, influence range, and detailed interaction processes. This study focuses on Hanwang Town, a region in the Qinling-Daba Mountains with extensively developed fault structures and frequent geological hazards. Detailed field survey data, photogrammetry, UAV technology, point cloud analysis software, laboratory experiments, and SBAS-InSAR technology were utilized to quantify the relationship between the Hanwang Fault Zone and distributed landslides with various formation patterns. The results reveal that the Hanwang Fault Zone primarily affects regional geological hazards by influencing the geometric and mechanical properties of rock masses and changes in topography. Specifically, the critical threshold distance of the Hanwang Fault damage zone is approximately 2.2 ± 0.3 km. Geological hazards are linearly distributed along the fault zone. The joint density of rock masses shows a strong negative correlation with their distance from the fault zone. The mechanical properties of rock masses rapidly decline due to fragmentation, affecting slope stability. Furthermore, the application of SBAS-InSAR technology has enabled the identification of differential uplift and subsidence rates in the vicinity of the fault zone, which has been identified as contributing factors in the formation of hydrogeological structures that are conducive to the occurrence of geological hazards. This study not only reveals the dynamic influence of the Hanwang Fault Zone but also provides an in-depth analysis of the development characteristics and damage mechanisms of geological hazards under the control of the fault zone based on typical cases. The findings open new perspectives for understanding the complex relationship between fault zones and geological hazards, providing scientific and technical support for disaster risk management and sustainable development strategies. • Fault activity significantly influences slope stability, triggering geological hazards. • Joint density analysis quantifies the fault damage threshold distance as 2.2 ± 0.3 km. • Fault activity affects the physical and mechanical properties of rock masses, further influencing slope stability. • Differential uplift and subsidence in fault zones drive geomorphic changes and hazards. • Four fault-controlled landslide formation patterns are identified and summarized. [ABSTRACT FROM AUTHOR]

The design of remediation works for the mitigation and prevention of the associated risk is needed where these geological hazards affect anthropized areas. Remedial measures for landslides commonly include slope reshaping, plumbing, drainage, retaining structures and internal slope reinforcement, while debris flow control works consist in open or closed control structures. The effectiveness of the remedial works implemented must be assessed by evaluating the reduction of the risk over time. The choice of the most appropriate and cost-effective intervention must consider the type of hazard and environmental issues, and selects, wherever possible, naturalistic engineering operations that are consequently implemented according to the environmental regulations or the design and specification standards imposed by the competent public administrations. The mitigation procedures consist of five basic steps: (a) acquisition of the knowledge of the hazard process; (b) risk assessment with identification of possible disaster scenarios; (c) planning and designing of specific remedial measures to reduce and/or eliminate the potential risk; (d) slope monitoring after application of remedial measures, (e) transfer of knowledge to the stakeholders. This paper presents two case studies describing the practice for the design of the mitigation measures adopted for debris flow and active landslide sites in North-Eastern Italy. The first case study is a debris flow site, for which, based on observation of past events and numerical simulations using the software FLOW-2D, the most suitable mitigation measures were found to be the construction of a debris basin, barriers and breakers. The second case study deals with an active landslide threatening a village. Based on the landslide kinematics and the results of numerical simulations performed with the code FLAC, hard engineering remedial works were planned to reduce the driving forces with benching and by increasing the available resisting forces using jet grout piles and deep drainage. [ABSTRACT FROM AUTHOR]

Landslides seriously threaten the safety of people's lives and property. A complete and accurate landslide catalog is an important material for studying landslides. The deep convolutional neural network method has attracted much attention due to its many advantages, but the complex structure of convolutional neural networks requires a large number of training samples, which restricts its development in landslide mapping. A convolutional neural network modeling method for fusing terrain features is proposed. First, a new landslide sample is constructed by superimposing terrain factors on the remote sensing image, and then a lightweight convolutional neural network (FF-CNN) is designed to extract and integrate spatial and spectral features, and finally the optimal model is trained for landslide recognition. Ablation experiments in Wenchuan, Sichuan Province, showed that the F1 score and average cross-merger ratio (MIoU) of the landslide identification and evaluation index of FF-CNN model based on spatial features were increased by 0.020 2 and 0.014444, respectively. After superimposing terrain factors on the remote sensing image, the F1 score and MIoU value of the landslide recognition evaluation index of the FF-CNN model increased by 0.0664 and 0.0482, respectively. Experiments in the Three Gorges Reservoir Area of Hubei Province and Hongkou Township, Dujiangyan City, Sichuan Province show that the FF-CNN model shows strong applicability and migration ability, and has great potential for landslide identification [ABSTRACT FROM AUTHOR]

The Hengduan Mountains Region (HMR) is one of the areas that experience the most frequent geological hazards in China. However, few reports are available that address the geological hazard susceptibility of the region. This study developed six machine learning models to assess the geological hazard susceptibility. The results show that areas with medium and high susceptibility to geological hazards as a whole account for almost 21% of the total area, while both are 18% when it comes to the single hazard of landslide and rockfall respectively. Medium and high geological hazard susceptibility is found in three parts of the HMR with different characteristics: (1) the central and southern parts, where the population of the region concentrates; (2) the northern part, where higher geological hazard susceptibility is found along the mountain ranges; and (3) the junction of Tibet, Yunnan, and Sichuan in the eastern part, which is prone to larger-scale geological hazards. Of all the potential influencing factors, topographic features and climatic variables act as the major driving factors behind geological hazards and elevation, slope, and precipitation are crucial indicators for geological hazard susceptibility assessment. This study developed the geological hazard susceptibility maps of the HMR and provided information for the multi-hazard risk assessment and management of the region. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The southeastern part of Cuba is considered to be the area of greatest seismic hazard in the country, due to its proximity to the Bartlett-Cayman fault zone, therefore a moderate to high intensity seismic activity can induce geological hazards in this region and impact the environment. The main objective is to propose a methodology that allows to evaluate the susceptibility to landslides and the liquefaction of soils induced by earthquakes for southeast Cuba through the geological characterization, identification of anthropized factors; morphotectonic characterization and seismological evaluation. New maps of landslide susceptibility and liquefaction induced by earthquakes are obtained as results; as well as the direct verification in the terrain of landslides; the main faults that cut the study area are identified; and the morphotectonic blocks and the relative movement between them are established and characterized. [ABSTRACT FROM AUTHOR]

Landslides, collapses and cracks are the main types of geological hazards, which threaten the safety of human life and property at all times. In emergency surveying and mapping, it is time-consuming and laborious to use the method of field artificial investigation and recognition and using satellite image to identify ground hazards, there are some problems, such as time lag, low resolution, and difficult to select the map on demand. In this paper, a 10 cm per pixel resolution photogrammetry of a geological hazard -prone area of Taohuagou, Shanxi Province, China is carried out by DJ 4 UAV. The digital orthophoto model (DOM), digital surface model (DSM) and three-dimensional point cloud model (3 DPCM) are generated in this region. The method of visual interpretation of cracks based on DOM (as main) -3DPCM (as auxiliary) and landslide and collapse based on 3DPCM (as main) — DOM and DSM (as auxiliary) are proposed. Based on the low altitude remote sensing image of UAV, the shape characteristics, geological characteristics and distribution of the identified hazards are analyzed. The results show that using UAV low altitude remote sensing image, the method of combination of main and auxiliary data can quickly and accurately identify landslide, collapse and crack, the accuracy of crack identification is 93%, and the accuracy of landslide and collapse identification is 100%. It mainly occurs in silty clay and mudstone geology and is greatly affected by slope foot excavation. This study can play a great role in the recognition of sudden hazards by low altitude remote sensing images of UAV. [ABSTRACT FROM AUTHOR]

Objectives: Traditional methods for remote sensing interpretation are difficult to identify historical geohazards covered by dense vegetation. For the purpose of interpreting the pre-seismic geohazards in the area of Panda Sea, Jiuzhaigou, and analyze the characteristics and distribution law, we propose a new methodology for geomorphologic identification masks and remote sensing interpretation regarding collapse, landslide and debris flow. Methods: Based on high-resolution LiDAR (light detection and ranging) data and data processing method of RRIM (red relief image map). RRIM is formed by the superposition of positive openness, negative openness and slope. RRIM method can supplement the shortcomings of the existing terrain visualization techniques, and apply the influence of environmental light to the terrain display, so that the visual interpretation can clearly identify the differences of landforms, and is more conducive to the identification and accurate interpretation of geohazards in mountainous areas. Results: Aiming at the Panda Sea area, which is the most seriously affected by Jiuzhaigou earthquake, the RRIM method is used to interpret the pre-seismic geohazards. A total of 311 pre-earthquake pre-seismic geohazards are interpreted and classified according to their characteristics, then are analyzed for spatial distribution. Conclusions: The verified results show that the high-resolution LiDAR data combined with RRIM is of great significance to improve the interpretation of geohazards of mountainous area with dense vegetation coverage, and provide data support for the geohazards prevention and risk assessment of the earthquake area in Jiuzhaigou. [ABSTRACT FROM AUTHOR]

Jiuzhaigou, located in the transitional area between the Qinghai–Tibet Plateau and the Sichuan Basin, is highly prone to geological hazards (e.g., rock fall, landslide, and debris flow). High-performance-based hazard prediction models, therefore, are urgently required to prevent related hazards and manage potential emergencies. Current researches mainly focus on susceptibility of single hazard but ignore that different types of geological hazards might occur simultaneously under a complex environment. Here, we firstly built a multi-geohazard inventory from 2000 to 2015 based on a geographical information system and used satellite data in Google earth and then chose twelve conditioning factors and three machine learning methods—random forest, support vector machine, and extreme gradient boosting (XGBoost)—to generate rock fall, landslide, and debris flow susceptibility maps. The results show that debris flow models presented the best prediction capabilities [area under the receiver operating characteristic curve (AUC 0.95)], followed by rock fall (AUC 0.94) and landslide (AUC 0.85). Additionally, XGBoost outperformed the other two methods with the highest AUC of 0.93. All three methods with AUC values larger than 0.84 suggest that these models have fairly good performance to assess geological hazards susceptibility. Finally, evolution index was constructed based on a joint probability of these three hazard models to predict the evolution tendency of 35 unstable slopes in Jiuzhaigou. The results show that these unstable slopes are likely to evolve into debris flows with a probability of 46%, followed by landslides (43%) and rock falls (29%). Higher susceptibility areas for geohazards were mainly located in the southeast and middle of Jiuzhaigou, implying geohazards prevention and mitigation measures should be taken there in near future. [ABSTRACT FROM AUTHOR]

The article presents the results of the landslide mapping in the area of the town of Polski Trambesh, central Northern Bulgaria. A total of 37 new landslides have been described, which have not been included in the landslide register so far. Landslides are classified by area, type and activity. Their location is mapped in a GIS environment. [ABSTRACT FROM AUTHOR]

Many UNESCO world heritage (WH) properties are exposed to geological hazards, or geohazards, which can turn into disasters if local authorities and site managers are unprepared. This paper analyzes for the first time the estimated exposure to geological hazards at 981 world heritage properties worldwide and the risk awareness of their managers. Initially the physical exposure of world heritage properties to four main geological hazards – tsunamis, landslides, earthquakes and volcanic eruptions – was estimated using open-access data from the global risk data platform and global volcanism program. Then, the periodic reporting registered data, which is part of the world heritage monitoring system and includes questions on the hazards that threaten each site, was examined to estimate world heritage site managers’ risk awareness. Finally, estimated and registered datasets enabled to identify focus groups of WH sites exposed to geological hazards worldwide. Results showed that a range of 39% (according open-access data) to 46% (according site managers) of world heritage properties are exposed to at least one of the four aforementioned geological hazards. When considering results from both datasets, the number of WH sites exposed to geohazards raise to 60%. The most frequent natural hazards affecting world heritage properties are earthquakes and landslides, whereas volcanic eruptions and tsunamis are less frequent. The most vulnerable regions are Asia and the Pacific and Latin America and the Caribbean, where more than half of the sites are exposed to at least one of geohazard. Furthermore, the analysis of 41 selected sites, based on real hazardous events, demonstrated that 38 out of 41 (92.7%) geohazard events were identified by one or the other dataset. The quality of the geohazard detection is less significant when both datasets are considered: only 22 out of 41 (53.7%) disaster cases were correctly estimated by both GRPD-GVP and PR-II databases. This difference could be due to the actual vulnerability of the sites, associated to their physical and social characteristics, and their environment, as well as coarse resolution of the open-access data, or to a lack of awareness – on the part of site managers – of the actual disaster risks associated with the hazard(s) affecting their properties. In order to obtain the global vision on the exposure to geohazards, it would be beneficial to combine these two types of information and consider them as complimentary. Moreover, analyzing real vulnerability and management systems at regional and local levels is indispensable to assess the actual degree of disaster risk affecting world heritage properties and define priorities for disaster management interventions. [ABSTRACT FROM AUTHOR]

Landslide plays an important role in landscape evolution, delivers huge amounts of sediment to rivers and seriously affects the structure and function of ecosystems and society. Here, a statistical analysis together with a field investigation was carried out on the Loess Plateau of China to address the challenges. The study tracks landslide-related deaths and collects knowledge about this natural hazard. Since the 1980s, 53 fatal landslides have occurred, causing 717 deaths. As the most important trigger, rainfall induced 40% of the catastrophic landslides, while other factors, i.e., human activities, freeze-thaw and earthquake, accounted for 36, 23 and 1%, respectively. Furthermore, landslide frequency and death toll related to human activities were increasing as time went on. Landslide also plays an important role in sediment delivery, especially in areas with steep terrain. Sediment discharge from landslides accounts for a considerable proportion of the total soil loss in the upper and middle reaches of the Yellow River. In some catchments of the Loess Plateau, landslides contributed over 50% of the total sediment discharge. The result shows that landslide is a widespread geologic hazard in the rural area of the Loess Plateau, China. [ABSTRACT FROM AUTHOR]

The April 21, 2007 shallow crustal earthquake (Mw 6.2) in the Aisén Fjord area triggered hundreds of landslides around the epicentral zone. Among those, several rock slope failures such as rock slides, rock falls and rock avalanches were induced on the steep fjord slopes. The violent impact of the disrupted rock masses into the fjord generated local tsunamis that caused ten fatalities and extensive damage to salmón farms located along the fjord shores. Field observations suggested that geotechnical and geomorphological factors controlled the landslide locations and failure modes, associated with the presence of faults and topographic relief, respectively. This event is an example of a geological hazard that has not been previously addressed in the Chilean Patagonian fjordland, revealing the need for identifying and understanding these geological phenomena in future hazard assessments in the región.El 21 de abril de 2007 un terremoto superficial cortical (Mw 6,2) en el área del Fiordo Aisén desencadenó cientos de remociones en masa en la zona epicentral. Entre éstas, se generaron varias inestabilidades en laderas rocosas escarpadas, tales como deslizamientos, caídas y avalanchas de rocas. El violento impacto de las masas disgregadas de roca en las aguas del fiordo generó tsunamis locales, que causaron diez víctimas fatales y un importante daño en granjas salmoneras ubicadas a lo largo de las costas del fiordo. Observaciones de terreno sugieren controles geotécnicos y geomorfológicos en la ubicación y modos de falla de las remociones en masa, asociados a la presencia de fallas y relieve abrupto, respectivamente. Este evento es un ejemplo de un tipo de peligro geológico que no ha sido previamente detectado ni abordado en los fiordos de la Patagonia Chilena, revelando la necesidad de identificar y comprender estos fenómenos geológicos en futuras evaluaciones de peligro en la región.

Risk evaluation is crucial for the construction projects in the areas with high risk of geological hazards. In this paper, based on the projects of Mengshan tourism area, geological hazard risk evaluation model is put forward based on the analysis of geological and environmental conditions as well as characteristics of construction works. Firstly, typical geological hazards of the area for evaluation are determined as collapse and landslide. And then, based on the comprehensive evaluation, 19 collapse zones and three landslide zones are determined in the area for evaluation. They are all stable at present in general, but some of them have high risk to collapse or landslide under rainstorm, weathering or other external forces in the future. At last, five regions are defined as dangerous, including three regions at level 1 and two regions at level 2. At the same time, some effective engineering measures are introduced to prevent the geological disasters according to the natural conditions and inducing factors of the hazards. Methods, procedure and the result put forward by the paper are useful and effective in risk evaluation of geological hazards, especially for the hilly and mountainous area similar as this case. [ABSTRACT FROM AUTHOR]

This paper presents the environmental impacts caused by surface mining and the ecological rehabilitation of Haikou phosphate deposits, Kunming, China. Surface mining entails the removal of the overburden to expose bare rock surfaces, not only causing destruction of pre-existing vegetation, but also occupying large areas of land for dumping the spoil. Severe environmental impacts are caused, e.g. rock desertification, poor forest stand structure, loss of biodiversity, aesthetic depreciation of the landscape, and the potential hazard of landslide and ground erosion. Ecological restoration has been conducted in a demonstration area since 1989 by means of control of geological hazards and revegetation of the disturbed areas. On-site dumping of waste rock for restoration of the abandoned mine area was adopted, providing a new mode of mining reclamation with high economic, environmental, and social value. Countermeasures for prevention and control of landslides included cut and fill technology, drainage, safety netting protection, retaining wall construction, and vegetation cover. By recruiting native plant species to the mine site and planting a forest imitating a natural mixed forest, the mine area was successfully revegetated. [ABSTRACT FROM AUTHOR]

The assessment of geological hazard is a topic with significant interest for the Balkans. During the last decade of twentieth century, most of the countries in the region have embarked on the road of a hasty transitory period from totalitarian regimes to democracy. Development of free market economy has given rise to uncontrolled movement of people, fast construction of housing and facilities and unproportioned accumulation of population around and in big cities. Besides Greece, an old member of European Union, and two newcomers in the organization, Romania and Bulgaria, the other countries are all hoping to enter the Union as faster as they can. Many different candidate or full-fledged member country programs of European Community offer a lot of joint and cross-border projects for constructing road infrastructure and facilities. As development accelerates in the Balkans and given the intensive geohazard elements that this territory exhibits, it becomes increasingly important to understand, study, and map these elements for being aware of the damage to the total environment these hazards might cause. The geohazard map and assessment of some Balkan countries has been carried out through two scientific meetings in Ohrid, Macedonia, and Tirana, Albania during 2007. The map is compiled in the Albanian Geological Survey, Tirana, Albania in the scale 1:1,000,000. As a base map, we used the topographic map produced by VGI, formerly Yugoslavia mapping authorities. As a seismic layer in our map, we used the values of peak ground acceleration obtained from Global Seismic Hazard Assessment Program. Two catalogs were constructed: The first one that contains the crustal earthquakes (hypocentral depth within first 70 km) and the second one that contains intermediate earthquakes (hypocentral depth below 70 km). This work is largely based on previous studies and investigations by earth scientists and specialists of each country comprised in this territory. In this respect, the map we constructed should be considered as a preliminary composite geohazard map with the possibility to be enriched and added with other new elements and data in the future. [ABSTRACT FROM AUTHOR]

Take account of the characters of road geological hazard and its supervision, it is very important to develop the Road Landslides Information Management and Forecasting System based on Geographic Information System (GIS). The paper presents the system objective, function, component modules and key techniques in the procedure of system development. The system, based on the spatial information and attribute information of road geological hazard, was developed and applied in Guizhou, a province of China where there are numerous and typical landslides. The manager of communication, using the system, can visually inquire all road landslides information based on regional road network or on the monitoring network of individual landslide. Furthermore, the system, integrated with mathematical prediction models and the GIS’s strongpoint on spatial analyzing, can assess and predict landslide developing procedure according to the field monitoring data. Thus, it can efficiently assists the road construction or management units in making decision to control the landslides and to reduce human vulnerability. [ABSTRACT FROM AUTHOR]

Abstract: The islands of the Azores archipelago are geologically young and located in a tectonically and volcanically active region. Not surprisingly, the islands are subject to many geological hazards, including earthquakes, landslides, and coastal erosion; some selected examples are discussed in this paper. As demonstrated by two recent earthquakes (1980, Terceira; 1998, Faial), the principal damage was related to one or more of these factors: (1) unsafe location of structures near faults; (2) unstable foundation soils; (3) poor quality of building materials and construction methods; (4) disregard of building codes; and (5) lack of building maintenance. Major landsliding events in the Azores (e.g., Ponta da Fajã, Ribeira Quente, and Fajã dos Cubres) typically are triggered by intense, long-duration precipitation and (or) earthquake-induced ground shaking. The loose, unconsolidated nature of the rocks and soils of these volcanic islands is another significant contributing factor, sometimes aggravated by ground instability caused by human activity. Coastal erosion is prevalent on the north coast of São Miguel and the south coast of Faial, mostly resulting from natural circumstances (e.g., steepness of cliffs, differential erosion, intense wave action during storms) and also from human activity (e.g., poorly engineered drainage works on cliff faces). Where severe, coastal erosion can pose a risk to populations and societal infrastructures situated near the tops of the seacliffs. To mitigate the risk of these and other geological hazards in the Azores, it is necessary to (1) prepare hazards and risks maps of the affected areas; (2) adopt prudent land-use planning that considers the hazards; (3) upgrade the building codes in the hazardous areas; (4) initiate slope-stabilization programs; (5) preserve the natural environmental integrity of the regions; and (6) educate the affected populace and governmental officials about the possibilities and consequences of hazardous processes. [Copyright &y& Elsevier]

The spatio-temporal distribution of geological hazards, including collapses, landslides, and debris flows, in Shaanxi province, China was studied based on data from 1951 to 2018. The potential impact factors, including the geomorphologic types, rivers, roads, rainfall, and earthquakes, were analyzed using Random Forests. The results indicated that most hazards occurred in summer (i.e., July–September) and were triggered by rainstorms. The freeze–thaw effect had a considerable contribution to hazards in the north. Spatially, most hazards in the north occurred in valley terraces of the Loess Plateau, while medium-relief terrane (relief ranged from 500 to 1000 m) in the southern Qinling Mountains were hazard-prone areas. The collapses and landslides were mainly affected by human factors in Northern Shaanxi, whereas in Southern Shaanxi geomorphology was the primary factor. Permeability was a dominant factor for debris flows. In addition, the 2008 Wenchuan earthquake had a remarkable influence on the spatial distribution of hazards. In contrast, for the situation in the Sichuan province, which was close to the earthquake epicenter, the Wenchuan earthquake triggered many collapse and landslide events in the southwest regions of Shaanxi province only on 12 May 2008. The thresholds for the three hazard types in the north and south regions were almost the same despite their distinctly different geologic characteristics. Through a sensitivity analysis, we found an appropriate dry period of 12 h for the area. [ABSTRACT FROM AUTHOR]