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This paper presents an approach to stream length-gradient index analysis to identify tectonic signatures. The graded profile of the Dez River in Zagros Mountains, Iran, indicates that the area has been tectonically disturbed, and it triggers landslide hazards. The high-gradient index shows that a steeper gradient could be potentially a signature for landslides identification. The digital surface models acquired by airborne LiDAR were used in this study to generate the HRDEM. Our result shows a great potential for improving landslide investigations by implementing stream length-gradient index derived from the HRDEM in conjunction with the landslide inventories data-set in the GIS environment. We also identified a correlation between the stream length-gradient index and the graded topographic profile with slopes and landslides. This empirical approach was verified by geodata analytics and landslide inventories data-set in conjunction with field observations. This study has identified the locations of high-gradient indices with susceptible to landslides. [ABSTRACT FROM AUTHOR]

The vast majority of the landslides in Hong Kong are triggered by rainfall. Surface drainage commonly provided on man-made slopes aims to prevent surface erosion and reduce infiltration. It plays an important role to avert slope instability. However, inadequate management of surface drainage could hamper its efficiency and often results in uncontrolled surface water flow contributory to landsliding. This paper provides insights on the importance of slope surface drainage management under the dense urban settings in Hong Kong from the landslide perspective. Selected landslides involving inadequately managed surface drainage are presented to highlight the key lessons learnt and areas deserving attention on various drainage aspects, including the design and detailing. It is noteworthy that inadequate surface drainage maintenance could exacerbate and lead to sizeable landslides even on engineered slopes. A review of landslide records over the years suggests that some landslides could have been averted had there been proper surface drainage maintenance. [ABSTRACT FROM AUTHOR]

Recently, the security and stability of submarine pipelines have attracted much attention in ocean engineering. In this paper, pipelines with a streamlined contour (wedge, airfoil, double-ellipse, and arc-angle hexagon) are designed in hopes of defending against the impact of submarine landslides, and the computational fluid dynamics (CFD) approach is used to investigate the interaction between submarine landslides and streamlined pipelines. The results show that the peak interactional force is more representative of the hazard level of pipelines imposed by submarine landslides. It is also found that the streamlined pipelines possess a significant advantage in reducing the drag force and lift force of landslide-pipeline interaction with a maximum lessening percentage of 66.32 and 40.17%, compared with a conventional circular pipeline. In addition, the influence of applying streamlined pipelines to engineering is briefly discussed, and the empirical equation for estimating the drag force and lift force of streamlined pipelines induced by landslides is recommended based on the numerical test results. [ABSTRACT FROM AUTHOR]

Due to global water consumption and an intensification of the resulting consequences there is a need for education regarding sustainable water consumption. Regarding Education for Sustainable Development, the ongoing water use of the industrialized countries needs to be discussed in the classrooms. Therefore, the aim of this paper is to present and use a questionnaire for the survey of students’ conceptions of sustainable water use. In order to enable educational reconstruction, conceptions about sustainable development and virtual water have been surveyed. The latter aspect of conceptions has been divided into different spatial conceptions and knowledge about water intense products. It has been shown, that the students’ conceptions are similar to scientific concepts, but learners also have their own conceptions. According to these findings conclusions for improved learning and teaching on sustainable water consumption are derived, to achieve more comprehensive students’ conceptions. [ABSTRACT FROM AUTHOR]

The purpose of the study is to reveal the knowledge level of pre-school children aged four to five about the concepts of forest and deforestation. The study group of the research consists of 29 children having pre-school education. The data were collected using a standardized open-ended interview technique. Results of the study showed that children have limited knowledge about concepts of forest and deforestation. A significant proportion of children could not define forest (f = 11) or deforestation (f = 9). Moreover, although a high number of children stated that the destruction of forests has negative influences on animals but only one child stated it would negatively affect the atmosphere, and only one child stated it would lead to landslides. The children think that the reasons for the destruction of forests are human-induced such as heating, paper production and use of construction materials. No significant correlation was found between the children's knowledge of these two concepts and their age or gender. In light of the findings of the study, it is suggested that ecological concepts should be directly incorporated into pre-school education programmes and that environmental education should be conducted outdoors based on daily life experiences. [ABSTRACT FROM AUTHOR]

Debris-flows are forms of landslides in mountainous regions that can potentially cause significant damage. Structural countermeasures to mitigate an entire debris-flow may become unrealistically massive and expensive. If the flow cannot be stopped completely, one may alternatively consider reducing the impact and velocity of the flow using energy dissipating structures. A debris-flow screen is such a countermeasure designed to dissipate energy. A screen is made by parallel grids, with some gaps, placed in the direction of the debris-flow on an elevated foundation. This structure acts as a filter for separating water from the saturated debris-flow to reduce its flow energy. This paper presents a laboratory model test investigating the effect of the screen with length (0.5m and 1.0 m) and opening width (2 mm, 4mm and 6 mm) in dissipating the debris-flow energy. The effectiveness of the screens was determined in terms of reductions in the run-out distance and the flow velocity. The importance of the screen length and the opening width is demonstrated. A hypothesis that the optimum opening size should be close to d50 of the solid material seems to be validated. The application of the laboratory observations to the field is indicated based on the energy line and scaling principles. [ABSTRACT FROM AUTHOR]

A new type of flexible debris-resisting barrier has been designed using the state-of-the-art analytical force approach for mitigation of channelised debris flow hazards in a hillside study area in Hong Kong. Unlike the conventional three-panel rectangular form, these flexible barriers were configured in a valley shape to geometrically fit in the incised drainage lines. The "design event" resulted in a calculated debris impact pressure of up to 400 kPa and over 10,000 kJ in terms of impact energy necessitating a site-specific design. The design involved advanced structural modelling of the highly non-linear behaviour of flexible barriers under debris impact giving rise to a large deformation. This paper presents the design and detailing of these valley-shaped flexible barriers, involving formulation of the design methodology, derivation of the multi-phase impact load model and optimisation of the barrier configuration. To support the design, numerical parametric studies were conducted to examine the barrier's impact behaviour. Two design initiatives were highlighted for enhancing the design robustness, including a rigorous approach to analyse the effects of the energy-dissipating devices on barrier performance and a robustness check to cater for adverse scenarios that could conceivably happen. Some suggestions on configuring a valley-shaped flexible barrier were given. [ABSTRACT FROM AUTHOR]

The Geotechnical Engineering Office (GEO) has been steering technical development work to facilitate enhancement in natural terrain landslide risk management in Hong Kong. Collaborations between GEO, the academia from both local and overseas institutes and geotechnical professions have been initiated in recent years to carry out studies on various aspects, including the development of design methodologies for debris-resisting barriers, the investigation of debris impact mechanics and debris-barrier interaction as well as the improvement of detailing of debris-resisting barriers. The concerted efforts have put Hong Kong in a leading position amongst other countries in the area of combating landslide risk. Many of the studies have brought about significant impacts to the engineering practice in many different regions, and have been made reference with by practitioners worldwide in establishing directions of technical development work on the subject. This paper presents the technical advances in natural terrain landslide risk mitigation measures in Hong Kong. It covers a wide spectrum of innovative studies jointly carried out by the GEO and various experts in respect of advanced numerical modelling, laboratory flume testing, centrifuge modelling and large-scale physical modelling, etc. These studies shed light on the potential of rationalising the present barrier design approaches. [ABSTRACT FROM AUTHOR]

An intense rainstorm on 21 May 2016 resulted a total of 34 natural terrain landslides in the vicinity of Sai Kung Sai Wan Road in the Sai Kung East Country Park, Hong Kong. One of these landslides was a large-scale failure with a source volume of about 2100m3. It was almost an order of magnitude larger than all the others. The debris severely eroded a road embankment, undermining the road and resulting in road closure. The nature of the landslide was unusual in that it was a structurally controlled rockslide, with a basal failure surface formed from a persistent, planar sheeting joint within columnar jointed tuff rock with a maximum depth of about 12 m, while the other landslides that occurred in the country park during the same rainstorm involved only shallow failures within the regolith. An investigation of this unusual landslide was undertaken to diagnose the probable mechanism and causes of the failure. As there was concern about further large-scale instability occurring in the adjacent hillside where the sheeting joint was inferred to extend into, the potential for further large-scale instability was assessed as part of the investigation. The key components of the investigation included detailed engineering geological mapping, ground investigation and engineering analyses. This paper presents the findings of the investigation. [ABSTRACT FROM AUTHOR]

Mitigation of natural terrain hazards through the use of flexible and rigid barriers has become a common type of geotechnical work in Hong Kong. The current design approach for these structural countermeasures typically involves separate debris mobility modelling and structural analyses of barriers subject to pseudo-static impact loadings. This practical approach, however, could not realistically account for the dynamic debris-barrier interaction. With a view to better capturing the response of barriers under the debris impact, effort has recently been devoted to developing an advanced numerical technique to model debris flows, barrier structural responses and the impact dynamics in a coupled manner. This paper presents some recent advances made in establishing the numerical technique of coupled analysis using a three-dimensional finiteelement computer code LS-DYNA. The methodologies of modelling the landslide debris mobility, the large-deformation non-linear behaviour of a flexible barrier under impact and the coupled analysis of debris-barrier interaction are introduced. Back analyses of selected landslide events and debris impact tests of flexible barriers for verification of the computer models are discussed. The coupled analysis enables detailed investigation of the energy balance involved in the impact process. Preliminary results of this energy analysis are also presented. [ABSTRACT FROM AUTHOR]

In this paper, decision trees machine learning algorithms, namely Random Forest (RF), Alternating Decision Tree (ADT), and Logistic Model Tree (LMT), were applied for modelling of susceptibility of landslides at the Luc Yen district, Northern Vietnam. These methods were evaluated to compare the performance of models and for selection of the best model for landslide susceptibility mapping and prediction. In this study, data of 95 landslides events were analysed with 10 landslide affecting factors using the Correlation-Based Feature Selection (CFS). These factors are land use, elevation, slope, distance to roads, aspect, curvature, distance to faults, rainfall, lithology, and distance to rivers. Receiver Operating Characteristic (ROC) curve, statistical indices (sensitivity, specificity, and kappa), and Chi-square test were utilised for validating and comparing the models performance. The modelling results show that the performance of RF model (AUC = 0.839) is the best with the data at hand compared to the ADT model (0.827) and the LMT (0.809) model. The RF should be applied for the better landslide susceptibility mapping and management. [ABSTRACT FROM AUTHOR]

This paper presents the results obtained by an audio-magnetotelluric (AMT) survey carried out crossing the western sector of Montemurro village (Southern Italy) affected by an intense hydrogeological instability. The AMT investigation was aimed to settle the question concerning the possible prosecution toward SE of the Eastern Agri Fault System whose surficial evidences could be blinded by extensive landslides phenomena and by anthropization of the territory. The AMT profile was oriented in NE-SW direction, orthogonal to the main geological structures of the investigated area. It crossed longitudinally the area affected by instability. The AMT model provides new insights on already known faults (i.e. Montemurro Faults) and imaged their in-depth immersion thus answering to still open geological question in the investigated areas. Furthermore, the high resolution of the model allowed the imaging of the boundaries, in terms of resistivity contrast, between material affected/unaffected by the sliding dynamics or characterized by an higher water content. The results provide new knowledge about the geological and geoelectrical structures in the area. They will be fully integrated with the results of the on-going research activities in the area and will represent an additional step for the multiscale and multiparametrical characterization of the Agri Valley geological setting. [ABSTRACT FROM AUTHOR]

Two rock topples with the opposite dip direction, observed in the Ribangliangzi hill and facing the China Provincial Highway S211, are located on the upper stream of the planned dam of Jinchuan Hydropower Station in China. The new site for submerged part of Highway due to reservoir impoundment is designed to be a tunnel crossing the Ribangliangzi hill. However, at this hill, the stratum facing the Dadu River dips southwestward, whereas the stratum facing the Xinzha Gully dips northeastward. Therefore, it's regarded as an important slope structure that may lead to an occurrence of landslide directly threatening the future tunnel excavation stability and slope stability along the highway. This paper reports for the geologic structures of the overturned strata, formative processes and mechanism for toppling on cataclinal slopes. It was concluded that the toppling on cataclinal slopes was caused by a combination of toppling and sliding. Furthermore, to analyse the conditions for toppling on cataclinal slope, the cantilever beam model was established and analyzed the minimum strata dip angle required for toppling more prone to occur on cataclinal slope and the critical length of rock stratum. The results reveal that the toppling will be more prone to occur on cataclinal slope while the strata dip angle is greater than 60°even if under a very small external force or without the assistance of external forces. [ABSTRACT FROM AUTHOR]

Assessment of the seismic vulnerability of a bridge structure relies on its structural characteristics and site data. However, seismically induced effects, such as landslides or rock falls, are often unknown at a bridge site, making seismic risk assessment difficult. The objective of this paper is to develop a methodology to produce susceptibility map for landslides and rock falls for the Lowlands of the Saint-Lawrence Valley based on geological and slope models, groundwater table and proximity to watercourses. The methodology is inspired by the concepts of the methodology of Hazus and adapted to the specificity of the region of study. The final map of susceptibility to landslides shows a predominance of high level of susceptibility. The digital inventory of landslides is compared to the landslides susceptibility levels. Sixty-eight percentage (68%) of landslides from the inventory are located on areas evaluated as highly or very highly susceptible. Therefore, the method of attribution of susceptibility level is well correlated to the inventory of landslides. This map is used within scoring procedures for a rapid assessment of the seismic vulnerability of bridges giving a better classification of the most vulnerable installations, improving the effectiveness of mitigation measures and the efficiency of emergency planning. [ABSTRACT FROM AUTHOR]

In the last years, great efforts have been made to improve the assessment of the temporal and spatial occurrence of rainfall-induced shallow landslides. Therefore, in this paper we used a physically based stability model (TRIGRS) in order to reproduce the landslide event occurred in the Monterosso catchment (Cinque Terre, Eastern Liguria, Italy) on 25 October 2011. The input parameters of the numerical model have been evaluated taking into account the land-use setting and paying specific attention to the evaluation of the spatial variation of soil thickness on terraced areas. The resulting safety factor maps have been compared with the inventory map of the landslides triggered during the event. The simulation results, which have been obtained also considering four different spatial resolutions of the digital terrain model, emphasize the influence of land use in shallow landslide occurrence and indicate the importance of a realistic spatial variation of soil thickness to enhance the reliability of the model. Finally, different triggering scenarios have been defined using hourly rainfall values statistically derived from historical data. The results indicate the proneness of the area to shallow landsliding, given that rainfall events with a relatively low return period (e.g. 25 years) can trigger numerous slope failures. [ABSTRACT FROM AUTHOR]

Lateral berms are often constructed to protect highway bridges against debris flows in mountainous regions. Currently, different solutions for lateral berm design are debated. The lack of standardization results in the improper design of lateral berms, limiting the mitigating effect. In this paper, a monitoring case of the mitigating effect of a lateral berm is introduced. The lateral berm was constructed through a bridge culvert at the alluvial fan of a debris-flow gully. In September 2008, a debris flow in this gully completely buried the lateral berm. The proposed numerical integral method was used to back analyse the flowing velocity and mud depth in berm. Results supported the speculation that abrupt decreases in mud depth and flow velocity in the lateral berm caused deposits that compressed the effective berm depth and resulted in overtopping flow. Therefore, we suggested reducing the berm width in order to increase the flow velocity in the berm. In June 2011, another debris flow with a smaller magnitude occurred in the gully, and the reconstructed lateral berm reportedly performed well to protect the bridge of Yalu highway. The case studies highlighted that berm width should be one of the main considerations in the berm design. [ABSTRACT FROM AUTHOR]

This paper proposes and implements an early warning and monitoring system for rainfall-induced landslide (named as EWMRIL) with a case study at the Nam Dan landslide (northern Vietnam). The proposed system consists of six sensor nodes and one rainfall station that are used to sense large amounts of data in real-time such as soil moisture, pore-water pressure (PWP), movement status, and rainfall. In addition, a new flexible configuration for the wireless communication system is proposed that is capable not only to save the energy consuming but also to ensure the reliability of the system. Using wireless communication system, the sensed data were sent to the computer station for analyzing and predicting the instability of the landslide in terms of factor of safety (FoS) using the finite element seepage analysis and the limit equilibrium slope stability analysis methods. These methods are available in the SEEP/W and SLOPE/W modules of the GeoStudio software. Based on the analyzing results, the system proposed three warning levels for the landslide Early, Intermediate, and Imminent. Experiment result in the rainy season from August to September 2016 has proven the validity of the EWMRILsystem. The result of this study is useful for landslide risk prevention and management in landslide prone-areas. [ABSTRACT FROM AUTHOR]

Landslides are a pervasive natural disaster, resulting in severe social, environmental and economic impacts worldwide. The tropical, mountainous landscape in South-West Mexico is predisposed to landslides because of frequent hurricanes and earthquakes. The main goal of this study is to compare landslide susceptibility maps in Guerrero derived using high-resolution LIDAR (light detection and ranging) data from both a manual landslide event inventory and an automated landslide inventorying algorithm. The paper also highlights the importance of applying LIDAR data in landslide inventorying and susceptibility mapping. We mapped landslides based on two approaches: (1) manual mapping using satellite images and (2) automatic identification of landslide morphology employing the Contour Connection Method (CCM). We produced a landslide susceptibility map by computing the probability of landslide occurrence from statistical relationships of inventoried landslides detected with LIDAR digital terrain models (DTMs) and derived landslide-causing factors using the logistic regression method. Our results suggest that the automated inventory derived through the CCM algorithm with LIDAR DTMs effectively minimizes the time-consuming and subjective manual inventorying process. The high overall prediction accuracy (up to 0.83) from logistic regression demonstrates the validity and applicability deriving reliable landslide susceptibility maps from an automated inventory; however, LIDAR data are required. [ABSTRACT FROM AUTHOR]

In this paper, a study aimed to assess the landslide susceptibility at a regional scale for the wide provincial territory of Matera (Basilicata region, southern Italy) and the relative risk along the main road corridors distributed in this area is presented. A heuristic-bivariate statistical predictive model was performed to assess and map the landslide susceptibility in the study area by using a polynomial function of eight predisposing factors, weighted according to their influence on the instability process. The resulting susceptibility map was successively used for assessing the landslide risk along the provincial road network. The importance of these roads, representing the main network connecting the urban centres, derives from the absence of an efficient integrated transportation system through the entire regional territory. The landslide risk was evaluated through a matricial approach, which has allowed to define the risk levels (low, medium and high) along road stretches by overlapping the consequences and hazard maps, by combining their corresponding classes in a matrix and by associating to each combination a risk level. The resulting landslide risk map provides support information for decision-making and for identifying the priorities for the design of appropriate mitigation plans. [ABSTRACT FROM AUTHOR]

Landslides are major natural disasters in mountainous areas, often caused by earthquakes and heavy rainfalls. Traditional manual delineation methods for identifying landslide features using optical imagery are inefficient, highlighting the need for automated detection techniques. Deep Convolutional Neural Networks (CNNs) have emerged as advanced solutions in computer vision for this purpose. Despite the reliance on pre-event and post-event imagery or various data sources like digital elevation models (DEMs), the success of deep learning models largely depends on the quality and availability of training data. This poses a challenge for their immediate application after a landslide. This study explores the transferability of a CNN model trained on data from the 2016 Kumamoto Earthquakes for detecting landslides in different events, specifically the 2018 Hokkaido earthquake and the 2017 Asakura Rainfall in Japan. These cases were chosen for their geographical similarities. The proposed deep transfer learning model, based on a DeepLabV3 + architecture built on a pre-trained ResNet50, automatically identifies landslide features without needing specific training data or model adjustments for each event. It achieved high accuracy in both cases, demonstrating CNNs' potential for broad application in landslide detection and enhancing disaster response efforts. [ABSTRACT FROM AUTHOR]

An effiecient landslide displacement prediction is important for early warning system of landslides. Based on time series method, the cumulative deformation of a landslide is decomposed into periodic and trend ones. A cubic polynomial is employed to forecast the trend deformation. Considering the periodic changes in rainwater and reservoir levels, the proposed model combines a convolutional neural network (CNN) with a gated recurrent unit (GRU) neural network to forecast periodic deformations. CNN effectively identifies the characteristics of the raw data, and GRU automatically controls the impact of historical information by adjusting the weights of the reset and update gates. C-GRU performance in predicting the periodic displacement is compared with GRU, and a backpropagation neural network optimised using particle swarm optimisation (PSO-BP). Monitoring points of Baishuihe landslide are employed to compare the performance of the various models. The findings show that the proposed model has strong data mining performance and deals with time series data efficiently. The new model can incorporate historical information more effectively than PSO-BP. Compared with GRU, the proposed model better captures the input data characteristics and improves the prediction accuracy. C-GRU achieves a low mean square error, representing a significant improvement in the accuracy of landslide predictions. [ABSTRACT FROM AUTHOR]

Loess landslide is one of the most harmful and serious geological hazards in the Loess Plateau of China. Early identification of potential loess landslide is an urgent need for its prevention. Traditional methods, e.g. support vector machines and decision trees, often suffer complicated data pre-processing, multitudinous causative factors, or low accuracy. This study aims to develop a high-performance loess landslide early identification model based on convolutional neural networks (CNNs). A case study was carried out in northwest Lvliang, China, where loess landslide is a major concern. Two hundred and six loess landslide cases were interpreted by comparing remote sensing images of two time phases, and were randomly divided into a training set (80%; 165) and a validation set (20%; 41). Four algorithms were developed, including a CNN structure with skip connection using data with (S–C) or without (S–N) slope crest and plain CNN structure using data with (P–C) or without (P–N) slope crest. The results show that the S–C structure is the most suitable for early identification of potential loess landslides because it achieved the highest overall accuracy (OA = 0.902) and largest area under the receiver operating characteristic curve (AUC = 0.932) on the validation set. [ABSTRACT FROM AUTHOR]

The mountain state of Uttarakhand constitutes a part of the North-western Indian Himalayan region and is inherently vulnerable to natural disasters. It is witnessing faster melting of glaciers and increased occurrences of disasters like cloudbursts, flash floods, landslides, landslide/glacial lake outburst floods, rock–ice avalanches, and debris flows. This study provides a comprehensive assessment of the influence of changing climate on the occurrence of natural hazards. It assesses the status of two major rapidly developing infrastructures in the state (viz., hydropower plants and transportation network) under climate variability. Detailed causative analysis of two major disaster events (in Kedarnath and Chamoli in 2013 and 2021, respectively) and associated destruction is presented to understand the vulnerability of infrastructure and communities to hazards. Based on the challenges identified, a unique two-fold framework is proposed, and recommendations are articulated for building resilient and sustainable mountain infrastructures and communities in the region. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) has achieved a remarkable place in solving complex problems in almost all disciplines. Based on the recent notable performances of machine learning and deep learning techniques for rapid and automatic landslide identifcation, it is observed that availability of quality training data, proper model training and associated cost are crucial for developing such frameworks. Therefore, the primary objective of the study is to propose a novel empirical algorithm, DvD, for rapid landslide identification using Sentinel-2 imagery and comparatively evaluate its performance to a deep learning architecture popularly used in feature extraction problems, binary semantic segmentation U-NET (BSS-UNET) framework. The empirical method has been investigated over a dataset diverse in topography and land cover to evaluate its efficacy. The proposed BSS-UNET framework is trained on the landslide database provided by the Institute of Advance Research in Artificial Intelligence (IARAI) in Landslide4Sense 2022 challenge which achieved a high mIoU value of 0.78 with 84.23% precision, 65% recall and 73.32 F1-score. The DvD algorithm outperformed the BSS-UNET framework and achieved 0.80 mIoU when applied to the IARAI dataset. The proposed empirical method has the potential to serve as large-scale rapid landslide inventory preparation subject to the availability of cloud-free satellite imagery. [ABSTRACT FROM AUTHOR]

This paper discusses critical issues related to the reliability of topographic monitoring systems such as ATS (Automated Total Stations), GNSS (Global Navigation Satellite System) and Ground Based InSAR focusing the attention on controlling the stability of networks infrastructure, which have influence on data correction procedures but are often taken for granted, and on integrating results in GIS (Geographic Information System), under a common reference framework and with respect to open-access ancillary data. The novelty of the paper lies in the demonstration of the efficiency obtained by a proper implementation of the system. Discussion makes reference to an active landslide by using ATS, GNSS and Ground Based InSAR in continuous and periodic mode. [ABSTRACT FROM PUBLISHER]

Teaching how to map the geomorphology of an area cannot be performed in a satisfying manner only in the lecture room, but requires practical exercises both in the laboratory and in the field. A preliminary study of existing geological maps, geomorphological legends and symbols used in Italy and of the landslide inventory preceded a detailed four-day-long field mapping campaign carried out by students in the framework of their MSc course on 'Geomorphological Mapping' at Bologna University. The Geomorphological Map at 1:5000 produced by some of these students is presented in this paper. The study area is located in the northern Apennines, a few kilometres East of Bologna, along the Idice Valley (N-Italy). Lithologies are mainly composed of clayey and marly sequences ranging in age from Cretaceous to Plio- Pleistocene, sands and sandstones of Pleistocene age, and Messinian gypsum, these last being the most resistant rocks. Besides the greater scale used in this map, allowing for a more detailed representation of the mapped features, this map also shows the recent evolution of landslides in this actively mass wasting area. [ABSTRACT FROM AUTHOR]

This paper illustrates a geographic information system (GIS) supported methodology for the assessment of landslide susceptibility. The methodology involves four operational steps: survey, site analysis, macroarea analysis and susceptibility analysis. The Survey includes the production (or acquisition) of a large-scale litho-technical map, a large-scale geomorphological map, a detailed inventory of past and present landslide events, and a high resolution DTM (Digital Terrain Model. Site analysis leads to the definition of discriminating parameters (commonly, lithological and morphometric conditions necessary but not sufficient to trigger a landslide of a given type) and predisposing factors (conditions that worsen slope stability but are not sufficient to trigger a landslide of a given type in the absence of discriminating parameters). The different predisposing factors are subdivided into classes, whose intervals are established by descriptive, statistical analysis of landslide inventory data. A numerical index, based on the frequency of landslide occurrence, quantifies the contribution of each class to slope instability. [ABSTRACT FROM AUTHOR]

Automatic DEM deformation detection without ground control points (GCPs) with its application in debris flow change analysis is an attractive but very difficult research topic. Based on the existing methods of M‐LZD and LMS‐LZD, this paper presents an improved method that takes both magnitude and relationship into account through allocating an appropriate weight to each observation and evaluating the contribution of each observation to deformation with the allocated weight. Such improvement enhances greatly the ability of DEM deformation detection. Compared with the M‐LZD and LMS‐LZD algorithm, using the multi‐temporal DEMs of the Puwaigou valley, along the Hengduan mountain ranges in the southwest of China, where debris flows occur frequently during each summer due to heavy rainfall and each Autumn due to rapid snowmelt, the experimental results demonstrate that our method has the highest detection accuracy (RMS) and detection percentage (capability) of over 50%. The advantages of our method are (1) it does not need GCPs and prior information and knowledge of the terrain surface, and (2) it can calculate simultaneously the volume and determine the spatial distribution of terrain surface changes of multi‐temporal DEMs. [ABSTRACT FROM AUTHOR]

The landslide hazard occurred in Taibai County has the characteristics of the typical landslides in mountain hinterland. The slopes mainly consist of residual sediments and locate along the highway. Most of them are in the less stable state and in high risk during rainfall in flood season especially. The main purpose of this paper is to produce landslide susceptibility maps for Taibai County (China). In the first stage, a landslide inventory map and the input layers of the landslide conditioning factors were prepared in the geographic information system supported by field investigations and remote sensing data. The landslides conditioning factors considered for the study area were slope angle, altitude, slope aspect, plan curvature, profile curvature, distance to faults, distance to rivers, distance to roads, normalized difference vegetation index, lithological unit, rainfall and land use. Subsequently, the thematic data layers of conditioning factors were integrated by frequency ratio (FR), weights of evidence (WOE) and evidential belief function (EBF) models. As a result, landslide susceptibility maps were obtained. In order to compare the predictive ability of these three models, a validation procedure was conducted. The curves of cumulative area percentage of ordered index values vs. the cumulative percentage of landslide numbers were plotted and the values of area under the curve (AUC) were calculated. The predictive ability was characterized by the AUC values and it indicates that all these models considered have relatively similar and high accuracies. The success rate of FR, WOE and EBF models was 0.9161, 0.9132 and 0.9129, while the prediction rate of the three models was 0.9061, 0.9052 and 0.9007, respectively. Considering the accuracy and simplicity comprehensively, the FR model is the optimum method. These landslide susceptibility maps can be used for preliminary land use planning and hazard mitigation purpose. [ABSTRACT FROM AUTHOR]

This paper presents an integrated geomorphological map of terrestrial and marine areas of northern Malta and Comino (central Mediterranean Sea) at 1:25,000 scale. The map is the result of terrestrial and marine analyses of different types of data such as aerial photos, digital terrain model of the seafloor and its acoustic backscatter image. The research is intended to emphasise the relationships and continuity of geomorphological features of both the land- and sea-scape, and outline their evolution. The map highlights the occurrence of fluvial, karst and gravity-induced landforms both on land and on the seafloor, such as palaeo-fluvial channels, sinkholes and landslides, which were shaped during sea level lowstands of the last glacial cycle. [ABSTRACT FROM PUBLISHER]

This paper presents the results of a geomorphological investigation of Mount Akdag landslide complex, located on the Western Taurus range, SW Turkey. The landslide, resulting in the collapse of a 5 km segment of Mount Akdag, covers an area of 9.8 km2and has a volume of about 3 × 108 m3. The 1:15,000 scale geomorphological map (Main Map) of the Akdag landslide presented here was produced from a combination of field studies and unmanned aerial vehicle-based DSM, including aerial-photo interpretation and geomorphometric analysis of landforms. The map shows contemporary and past geomorphological hillslope processes and landforms associated with the landslide complex. Our new map suggests that the Akdag landslide was a complex rockslide consisting of multiple landslide types that developed through various movements. We found that 43 highly developed and active mass movements on the main body and side slopes of the landslide made a major contribution to the sediment input. The sediment produced in the upstream severely threatens the touristic site of Saklikent Canyon in the lower catchment via an increasing magnitude of torrents. This map will provide important data for local and national administrators regarding monitoring up-to-date mass-wasting processes, understanding the landslide and its related sedimentary dynamics, and implementing risk assessment and necessary precautions. [ABSTRACT FROM PUBLISHER]

The Crati Graben is a depression of Plio-Holocene age mainly controlled by extensional N–S striking faults and WNW–ESE transcurrent faults, in its northern and southern extremity. It is characterized by high landslide susceptibility due to the particular geo-structural pattern and seismotectonic characters. Landslides involve many villages, infrastructure and food crops, bringing serious economic and social damage. The seismotectonic and landslidesMain Mapof the Crati Graben, described in this paper, represents an update in detail of the framework of landslide risk areas and shows the main active and recent faults of the Crati Graben. The landslides and the faults, have been identified and classified, originally at detail scale (1:5000) and, then, represented at 1:50,000 scale. The geo-structural and geomorphological data were analysed in a geographic information system. The work has revealed a correlation between the trend of faults with respect to the distribution of landslides and of the historical and instrumental seismicity. The work presents an updated knowledge framework of risk conditions of the study zone, where risk areas related to slope instability are hierarchically classified according to the destructive potential of landslides. This document may be therefore a useful reference in planning and prioritising in the design of interventions for the safety of slopes and waterways. [ABSTRACT FROM AUTHOR]

This paper presents the results of geomorphological investigations carried out in Basilicata region (Southern Italy) in the sector of the youngest foredeep (Bradano trough) relative to most of the communal territory of Pisticci. The importance of the chosen area mostly lies in the presence of diffuse running-water landforms and landslides affecting urban areas. The geomorphological processes are linked with Quaternary tectonic uplift affecting the Apennine front-Bradanic foredeep sectors. A series of field surveys, supported by aerial photo interpretation, have led to the production of a geomorphological map at 1:35,000 scale which outlines the main processes and related landforms recognised in the study area. The latter are the result of the complex interplay of structural, gravitational and fluvial processes. Particular attention has been devoted to the recognition, identification and mapping of landslides which affect the slope, locally giving rise to hazardous conditions. [ABSTRACT FROM AUTHOR]

Multi-temporal InSAR technique can implement continuous earth surface deformation detection with long time scale and wide geographical coverage. In this paper, we first employ the Small Baseline Subset method to survey potential landslides in Guide County, Qinghai Province, which is identified as a loess landslide prone area for geological and climate conditions. Two anomalous deformation regions are detected by L-band Phased Array and L-band Synthetic Aperture Radar stacks. Then, qualitative and quantitative evaluations of the measuring points are given for understanding the distribution regularity of deformation. Finally, preliminary correlation between the time-series deformation and triggering factors is analyzed to explore the driving mechanism for landslide movement. The results demonstrate that L-band SAR has high potential in landslide monitoring applications and can be used as the basis for landslide recognizing, precursory information extracting, and early warning. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, disk-based discontinuous deformation analysis (DDA) is applied to simulate a real landslide triggered by an earthquake. For this purpose, the kinematic behaviour of the Donghekou landslide triggered by the Wenchuan earthquake is simulated and the results obtained using disk-based DDA are compared with actual data. The comparisons show that there is a good agreement between the results obtained using disk-based DDA and observed data. The simulation results provided an understanding of the failure behaviour and temporal evolution of the landslide. This study shows that disk-based DDA is a practical numerical tool that can be used to simulate the post-failure behaviour of landslides triggered by an earthquake. [ABSTRACT FROM PUBLISHER]

This paper illustrates the potential of Sentinel-1 for landslide detection, mapping and characterization with the aim of updating inventory maps and monitoring landslide activity. The study area is located in Molise, one of the smallest regions of Italy, where landslide processes are frequent. The results achieved by integrating Differential Synthetic Aperture Radar Interferometry (DInSAR) deformation maps and time series, and Geographical Information System (GIS) multilayer analysis (optical, geological, geomorphological, etc.) are shown. The adopted methodology is described followed by an analysis of future perspectives. Sixty-two landslides have been detected, thus allowing the updating of pre-existing landslide inventory maps. The results of our ongoing research show that Sentinel-1 might represent a significant improvement in terms of exploitation of SAR data for landslide mapping and monitoring due to both the shorter revisit time (up to 6 days in the close future) and the wavelength used, which determine an higher coherence compared to other SAR sensors. [ABSTRACT FROM AUTHOR]

Landslides are a major geohazard, which result in significant human, infrastructure, and economic losses. Landslide susceptibility mapping can help communities plan and prepare for these damaging events. Digital elevation models (DEMs) are one of the most important data-sets used in landslide hazard assessment. Despite their frequent use, limited research has been completed to date on how the DEM source and spatial resolution can influence the accuracy of the produced landslide susceptibility maps. The aim of this paper is to analyse the influence of spatial resolutions and source of DEMs on landslide susceptibility mapping. For this purpose, Advanced Spaceborne Thermal Emission and Reflection (ASTER), National Elevation Dataset (NED), and Light Detection and Ranging (LiDAR) DEMs were obtained for two study sections of approximately 140 km2in north-west Oregon. Each DEM was resampled to 10, 30, and 50 m and slope and aspect grids were derived for each resolution. A set of nine spatial databases was constructed using geoinformation science (GIS) for each of the spatial resolution and source. Additional factors such as distance to river and fault maps were included. An analytical hierarchical process (AHP), fuzzy logic model, and likelihood ratio-AHP representing qualitative, quantitative, and hybrid landslide mapping techniques were used for generating landslide susceptibility maps. The results from each of the techniques were verified with the Cohen's kappa index, confusion matrix, and a validation index based on agreement with detailed landslide inventory maps. The spatial resolution of 10 m, derived from the LiDAR data-set showed higher predictive accuracy in all the three techniques used for producing landslide susceptibility maps. At a resolution of 10 m, the output maps based on NED and ASTER had higher misclassification compared to the LiDAR-based outputs. Further, the 30-m LiDAR output showed improved results over the 10-m NED and 10-m ASTER output, indicating that finer resolution does not necessarily result in higher predictive accuracy in landslide mapping. The source of the data-sets is an important consideration and can have significant influence on the accuracy of a landslide susceptibility analysis. [ABSTRACT FROM AUTHOR]

We present and experimentally demonstrate a seismic ambient noise monitoring optical fibre sensor for early warning detection of sinkholes. The developed optical fibre sensor is designed for warning alert of subsidence and cover collapse sinkholes. The progressive process of sinkhole development causes structural change in the subterranean surface. The impact of this change and its influence on the subsurface acoustic modes was detected in the form of variations in the spectral content of the ambient noise signals monitored in the subsurface. Structural surface integrity was monitored through frequency response as the void increased. Vibrational states relating to unsteady structural conditions were identified. Significant instability events were captured giving timely warnings before collapse. The polarisation based single mode fibre sensor and monitoring method is proposed for implementation in a phase sensitive distributed acoustic sensor setup. Peak frequencies in the micro-seismic noise band of 0.1 Hz to 1.0Hz were observed through cavity development and growth. Extended peak frequency shifts and bandwidth in the band >1Hz were recorded, indicating weakness and imminence of collapse. Early warning detection by the structural field model was achieved prior to the sudden subsurface failure which results in collapse sinkholes. By monitoring variations in the vibrating frequency modes when a subsurface cavity develops within the structure, trigger events and collapse precursor conditions are identified. We have successfully demonstrated an early response warning annunciator by using an algorithm to analyse combinational characteristics of the spectral components of the detected signals. The fibre sensor reduces the risk and socio-economic impact of infrastructural damage due to sudden collapse of sinkholes and has extended potential of monitoring earthquakes and landslides. [ABSTRACT FROM AUTHOR]

The north-eastern border of CA represents the accretionary system developed during its continuous collision with Apulian block. The tardive oblique tectonic component is highlighted by pervasive NW-SE crustal transpressive left-lateral strike slip faults developed from the Upper Miocene to Quaternary tectonic stages. The seismotectonic and landslides Main Map represents the update of the main faults, the style of their arrangement and kinematics, the seismotectonic features and landslide area distribution with risk implications. Seismotectonics allows us to recognise a vertical crustal zonation with the distribution of earthquakes and their focal mechanism solution. The prevalent modality of ruptures depicts a mainly transcurrent and compressive solution in mid-lower crust portions respectively. This data, together with the historical seismicity analysis of the area, lead to consider the NW-SE strike-slip faults improved on the Main Map, as recent and tectonically active. The areal distribution of landslide and susceptibility of the area is due to the interaction between seismotectonic peculiarity, lithological typologies and fault zone architectures. Landslides and flood phenomena of this sector involve many municipalities, major and minor infrastructures and economic and social activities. The landslides and the faults have been identified, mapped and classified, originally at detail scale and, then, represented at 1:50,000 scale in the Main Map, included as supplementary material. The geo-structural and geomorphological data were analysed in a geographic information system allowing data management and implementation. The work presents an updated knowledge framework of risk conditions of the study zone, available to plan and reduce the fundamental elements that determine the landslide and seismic risks in this region. [ABSTRACT FROM AUTHOR]

Periodically monitoring landslides is a key factor for supporting the realisation of hazard warning systems and risk reduction in the corresponding neighbourhood areas. Although satellite remote sensing solutions can be considered for low spatial resolution monitoring, this approach is still inappropriate for high spatial resolution investigations. Ground-based Radar Interferometry is also a widely used technique that allows for working at a proper spatial resolution, but it can often be an overbudget solution for most applications. Instead, photogrammetric surveys based on Unmanned Aerial System (UAS) imagery appear as a very interesting approach in terms of both spatial resolution and flexibility in temporally repeating the survey. Motivated by this observation, this work investigates the use of multi-temporal UAS surveys for landslide monitoring. To be more precise, Digital Image Correlation (DIC) has been applied to orthomosaics generated from different UAS photogrammetry surveys to compute the area's deformation map. Compared with a reference GNSS survey, the results obtained using NHAZCA IRIS software and an in-house DIC approach show a deformation estimation accuracy of approximately 0.1 m, a reasonable accuracy for landslides moving at moderate velocity. [ABSTRACT FROM AUTHOR]

In Italy, landslides are one of the main geological hazards. Sometimes urban areas are affected by deep-seated gravitational slope deformations (DGSDs) that can lead to a potentially catastrophic failure and trigger a secondary collateral landslide. In these cases, monitoring is important for early warning and risk reduction. In this study, we analyzed DGSDs, in particular, lateral spreads, and landslides in the inhabited areas of Ulassai, in eastern-central Sardinia. Starting from high-resolution geostructural and geomorphological surveys of lateral spread, integrated with high-resolution digital elevation models acquired by UAV (Unmanned Aerial Vehicle), we created geological 3D models of the slope deformations. To better understand the kinematics and temporal evolution of unstable slope deformation, a monitoring system, consisting of Space-borne Interferometric Persistent Scatter Synthetic Aperture Radar (PS-InSAR), GNSS antennas, tiltmeters, and extensometers, was performed. PS-InSAR analysis confirmed by GNSS periodic measurement identified downslope movement of up to 10 mm per year in the lateral spread. Continuous acquisition by extensometers and tiltmeter recorder displacement in large block inclinations and opening and closing of fractures since 2021. Integrated data analysis will be essential to define the threshold for a future 24/7 early-warning system. [ABSTRACT FROM AUTHOR]

Landslides, one of the most common mountain hazards, can result in enormous casualties and huge economic losses in mountainous regions. In order to address the landslide hazards effectively, the geological society is required not only to develop in-depth understanding of landslide mechanism but also to quantify its associated risk. In this article, landslide risk assessment is categorised into two types, hard and soft risk assessments, and reviewed separately. The hard approach focuses on the mechanics and numerical simulations of individual landslides, subsequent consequences, and their uncertainty quantifications and probabilistic analyses while the soft approach explores the quantification of disaster risk components such as hazard and vulnerability at different scales of concern. It is hoped that this article can serve as a time capsule to link the preceding and following of landslide risk assessments and shed some light on future studies. [ABSTRACT FROM AUTHOR]

In this study, a stability analysis approach for fractured rock mass slopes is proposed by combining the strength reduction method (SRM) with the undirected graph theory (UGT). First, the original shear strength parameters of all the fractures are divided by the same reduction coefficient to generate new shear strength parameters, which are used for numerical simulations of the fractured rock mass slope. Second, the connectivity of the failure fractures is analyzed with a self-developed code, which is developed based on UGT. If no fracture clusters are fully connected from the top of the slope to the toe or free face of the slope, the slope is considered to be stable, and the reduction coefficient is incremented. The above calculation procedures are repeated until there is exactly right a fracture cluster is fully connected (i.e. slope is leaded to critical state). The reduction coefficient that coincides with the critical state is considered as the safety factor of the slope, and the fractured rock mass encompassed by the connected failure fractures is regarded as the unstable part of the slope. Finally, the proposed method is applied to analyze the stability and the potential failure range of a steep slope to verify its validity. [ABSTRACT FROM AUTHOR]

This paper illustrates the contribution of Persistent Scatterer SAR Interferometry (PSInSAR) technique to landslide detection, using interferometric data acquired in C-band by European remote-sensing satellite (ERS) 1/2 and environmental satellite (ENVISAT) satellites. The main purpose is to update a pre-existing landslide inventory map, by changing or confirming the landslide geometry and state of activity and eventually, identifying new phenomena.This work presents an application of satellite remote sensing to analyse ground displacement movements in the Setta basin, located on the northern Appennine (Bologna province, Italy) and extended up 268 km2.The proposed methodology, resting upon pre-existing works already consolidated in the scientific community, combines interferometric measures with aerial imagery and other auxiliary data, in order to detect landslide indicators, finally validated with field surveys. The use of an activity matrix allows the identification of the state of activity of landslide phenomena with respect to the velocity of the radar displacement rates. Field validations are carried out in the areas that are more relevant because of the highest ground velocities and the presence of structures extensively affected by ground movements.The final updated landslide database of the Setta basin, based on Persistent Scatterer Interferometry analysis andin situchecks, consists of 1550 landslides, 236 of which have persistent scatterer information. [ABSTRACT FROM PUBLISHER]

Numerous mass movements of different typology characterize both mountainous and piedmont sectors of the Emilia-Romagna Region (Apennine chain, North Italy). Although a less spatially frequent landslide typology within the region, rock falls represent severe threats to buildings, roads and persons due to their high propagation velocity. This paper presents an extract of the Emilia-Romagna regional map of the rock fall runout areas at a scale of 1:25,000. The analysis of rock fall runout areas was based upon a three-dimensional morphological method (TDM). The zone presented in theMain Mapencompasses the area surrounding Mount Cimone, in the Emilia-Romagna Region. The proposed regional map of rockfall runout is noteworthy for planning actions and strategies aimed at the prevention and reduction of landslide risk at a regional scale. [ABSTRACT FROM AUTHOR]

This paper presents the results of geomorphological investigations carried out in Basilicata region (southern Italy) from the most external thrust front of the Apennines, where the town of Craco is located, to the adjacent sector of the Apennines foredeep (Fossa Bradanica; Pisticci area). The importance of the chosen area mostly resided in the presence of really diffuse running-waters and gravity-induced landforms which strictly affect urban areas. The geomorphological processes are linked with the Quaternary tectonic uplift affecting the Apennine front-Bradanic foredeep sectors. Series of field surveys, supported by aerial photo-interpretation, have led to the production of a geomorphological map at 1:16,000 scale which outlines the main processes and related landforms recognized in the study area. The latter are the result of the complex interplay of structural, gravitational and fluvial processes. Particular attention was devoted to the recognition, identification and mapping of landslides which affect the slope of the main villages (Craco and Pisticci), locally giving rise to hazardous conditions. [ABSTRACT FROM AUTHOR]

In this paper, a landslide-induced surge wave and its overtopping of a dam is simulated using a coupled ISPH model. In the model, the mirror particle treatment was employed to simulate the moving structures and a particle symmetry criterion was enforced for free surface judgment. A telescopic boundary is presented for the landslide body motion treatment. The model is first used to simulate the two types of surge wave induced by submarine and aerial landslides and the simulation results are compared to the previously published experimental data. Then, in order to study landslide-induced wave propagation and especially the overtopping of a dam, laboratory experiments were conducted in which the landslide motion, the wave gauge results and the total overtopping volume were presented and compared to the numerical results. It was found that the present numerical model can accurately simulate the entire process of surge wave generation, propagation and overtopping of a dam. [ABSTRACT FROM AUTHOR]

Landslides are one of the most damaging and threatening hazards associated with seismically induced slope movements. Estimations of support conditions for slope displacements are important for taking preventive measures to avoid landslide events in future. California's Division of Mines and Geology (DMG) procedure is utilised in the present paper for estimating the slope failure mechanism under seismic conditions. In this study, the DMG procedure has been explained and has also been incorporated in a Geographic Information System (GIS) using Arc-GIS software from Environmental Systems Research Institute. Further, it is utilised for establishing a seismically induced slope displacement map for the Skien municipality area of Telemark County in Norway. The motivation for selecting this site was the availability of geotechnical parameters for the site. Three different displacement maps have been produced for earthquake scenarios of magnitude 5, 6 and 7, respectively. The maximum displacement of 133 cm is estimated for earthquake scenario of magnitude 7. It is noticed that the sensitive areas for slope failure remain the same under different earthquake scenarios. A displacement tool based on the DMG procedure has been created in the Arc-tool box in Arc-GIS software. This tool minimises the efforts for inserting formulas for making raster displacement maps. By using the displacement tool one can generate final products like displacement maps automatically at high accuracy and in quick time. The prepared slope displacement maps of study area are used for landslide susceptibility zonation (LSZ) map preparation. The LSZ maps are useful for landslide hazard assessment and further can be utilised by planners, civil engineers and local administrators for town planning and policy-making. [ABSTRACT FROM AUTHOR]

In this paper a geomorphological map of the Rotolon landslide is presented. This cartographic product was obtained using a combination of accurate field surveys together with airborne Lidar analysis, aerial photo interpretation and thermographic field surveys within a GIS. The map was prepared in order to analyze the morphological features of the landslide and therefore improve interpretation of the GB-InSAR data. This monitoring device was installed on the site after the detachment of a debris mass of 225,000 m3on 4 November 2010. The main purpose of the post-event activities, including the geomorphological characterization, was to detect the processes acting on the landslide, evaluate the hazard related to each phenomenon, understand the landslide kinematics and define the residual risk for the area. The geomorphological map suggests that debris production and detachment are hazardous phenomena that involve the surficial detrital cover of a bigger and more complex landslide. The latter has the typical characteristics of a deep-seated gravitational slope deformation. The distinction between secondary processes, which appear to be the most hazardous in the short-term, and deep seated ones, demonstrates that accurate mapping provides important information for local administrations and decision makers, allowing them to prepare landslide susceptibility and hazard models. [ABSTRACT FROM AUTHOR]

Identification of landslides at the regional scale has always been a challenging problem. Various automatic landslide identification methods, mainly relying on spectral information from aerial photographs or satellite imagery, have been developed. This paper proposes a semi-automatic approach to identify locations of small-sized shallow debris slides and flows using airborne lidar (light detection and ranging) data. Cells related to landslide components were first extracted by using a new method based on local Moran’s I (LMI). Subsequently, cell clusters representing landslide components and other terrain objects were discriminated through geometric and contextual analysis at cluster level. The approach was tested in a study area in Hong Kong and the identification result was verified by a landslide inventory. Locations of 93.5% of recent landslides and 23.8% of old landslides were identified by the proposed approach. The result indicates that the proposed approach is able to identify both recent and old landslides with distinct morphological features. However, the proposed approach also identified a large number of locations (77.6% of all locations) unrelated to landslides. These locations may correspond to terrain objects with similar morphology to debris slides or flows, and indicate rough terrain in the study area. In addition, the effects of DEM (digital elevation model) resolution on landslide identification were analysed by applying the LMI-based method to digital elevation models (DEMs) at different resolutions. The results indicate that the smoothing effect caused by lowering DEM resolution led to extraction of fewer landslide components. [ABSTRACT FROM AUTHOR]