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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]

This study reported a landslide hazard pattern considering the dependence of hazard components, with the example of Heilongjiang Province. The spatial and magnitude probabilities of landslides were first constructed to develop a potential link with the annual occurrence rate. Thereafter, landslide hazard considering component dependence was derived based on a modified Poisson model, and presented via the exceeding probability under the scenarios of combining two magnitudes (greater than or equal to 30,000 and 100,000 m³ ) and four periods (1, 3, 5 and 10 years). Results show that the Poisson model refined is not only a temporal probability function conditional on the magnitude and space, but can capture the hazard definition accurately. Moreover, the exceeding probability is related to the location of the raster, magnitude and the time interval of the landslide. Geographically, the areas with high exceeding probability are concentrated in the central and southeastern parts of the study area. Further, landslide probability dynamically varies with the magnitude and time interval, increasing gradually with the time interval, but decreasing with the landslide magnitude. This study is significant to resolve the conflict between the independence assumptions of the hazard calculation and the conditional attributes in the hazard definition. [ABSTRACT FROM AUTHOR]

Landslides represent one of the most frequent geodynamic phenomena in Slovakia. This contribution focuses on the relations of the selected landscape attributes and landslides in flysch area of the Western Carpathians. We presented three statistical methods of assessing and making a prognosis of the landslide hazard: multivariate, factor and zonal analysis. These methods complement each other and their aim is to analyse and recognize natural processes, which trigger the landslides in a more complex way. With multivariate analysis, we evaluated mutual interactions between the input attributes and determined their level of impact on landslide hazard. Using factor analysis, we extracted latent factors with the highest factor loads and identified the main factors that could trigger landslides. Areal extension of landslides in individual landscape attributes was expressed by zonal analysis, based on the superposition of the individual vector layers. Our evaluation shows that the slope predisposition to landslides is predominantly given by the geological, hydrogeological and morphological conditions. The proposed landslide risk assessment procedure allows for the functional sustainable development of the landscape development planning documents. The results presented in this paper are relevant for the area formed by flysch rock (Alps and Carpathians), but also for areas where clastic sediments alternate rhythmically. [ABSTRACT FROM AUTHOR]

An interdisciplinary study has been adopted to investigate the upper Maira Valley (Western Alps, Italy). A geological map of an unmapped area, of about 12 km2, at scale 1:10.000, has been realized. The combination of field surveys, GIS database creation, aerial photo observation, local archival data consultation, geo-structural analysis and drillholes re-interpretation outlined a relationship between structures and landforms. A ductile and brittle deformation history with the definition of four discontinuity systems (F1-F4) has been detected. Where the fracturation is intense, rock-falls and topplings are triggered. In area associated with a homogeneous presence of weathered cover, debris flows were identified. The geo-structural pattern obtained from the surveys in the upper Maira Valley allowed characterizing detachment zones of the slope overlooking Acceglio town. The Gollone Landslide is an excellent case study to unravel the structural-morphological interaction and the kinematic evolution due to its framework. [ABSTRACT FROM AUTHOR]

Numerical simulation models of water flow in variably saturated soils are important tools in water resource management, assessment of water-related disasters and agriculture. Richards equation is one of the most used models for the fluid flow simulation into porous media. It is a partial differential equation whereby analytical solutions are only possible after applying a number of restrictive assumptions. Therefore, the derivation of efficient numerical schemes for its approximated solution has to be computed by discretization methods. We propose a numerical procedure considering a simplified linearization scheme that makes it adaptable to parallel computing. A comparison in computational performances with three other numerical procedures is detailed for a large computation, including the assessment of the landslide hazard in real areas. We demonstrate the efficiency of the proposed numerical procedure by comparing the results we obtained with a parallel code. [ABSTRACT FROM AUTHOR]

In this study multi-hazard risk assessment is carried out in Arithang ward, one of the major wards within Gangtok Municipal Corporation, with the objectives of (a) landslide and earthquake hazard mapping of Gangtok city with analytical hierarchy process (b) vulnerability mapping in Arithang ward and (c) semiquantitative and semiqualitative risk analysis. Landslide hazard zonation (LHZ) depicts that very high and high hazard zone occupies 6% and 17% of the Gangtok city whereas 60% and 18% of area falls under medium and low hazard category respectively. With respect to seismic hazard susceptibility 13% and 22% of area falls under very high and high category respectively. Semiquantitative risk analysis reveals that majority of the residential buildings are concentrated in low earthquake and landslide hazard zone followed by 39% and 35% within medium class. Only 0.6% and 7% of residential buildings are found in high earthquake and landslide hazard zones. Bamboo and wood made buildings are found to cluster within very high class of landslide hazard. About 61% of multistoried buildings are placed within low zone of LHZ. Risk analysis reveals that buildings at the eastern and western part of Arithang ward come under high risk with respect to earthquake and landslide. [ABSTRACT FROM PUBLISHER]

The diagnosis of landsliding at the slope scale resulted from synergic geohydromechanical analyses of the slope factors, which should represent the first step to assess landslide hazard. According to the methodological approach discussed in the paper, the landslide hazard analysis should start from a phenomenological interpretation of the slope behaviour, including the definition of the slope factors, getting then to a quantitative prediction of the slope evolution with time. This quantitative evaluation should result from limit equilibrium analyses and numerical modelling, both of them performed considering the outcomes of the phenomenological reconstruction. Therefore, the understanding of the slope factors and of the landslide mechanism at the slope scale should drive the landslide hazard assessment, through analyses performed for different levels of diagnosis (phenomenological, analytical and numerical). Some landslides, representative for chain slopes in the Italian peninsula, are discussed in the paper in order to show the maturity of the geohydromechanical diagnosis of landslide hazard and, hence, to properly design the mitigation actions. A methodology for intermediate to regional landslide hazard assessment, based on geomechanical interpretations, is finally proposed. [ABSTRACT FROM AUTHOR]

The current paper presents landslide hazard analysis around the Cameron area, Malaysia, using advanced artificial neural networks with the help of Geographic Information System (GIS) and remote sensing techniques. Landslide locations were determined in the study area by interpretation of aerial photographs and from field investigations. Topographical and geological data as well as satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. Ten factors were selected for landslide hazard including: 1) factors related to topography as slope, aspect, and curvature; 2) factors related to geology as lithology and distance from lineament; 3) factors related to drainage as distance from drainage; and 4) factors extracted from TM satellite images as land cover and the vegetation index value. An advanced artificial neural network model has been used to analyze these factors in order to establish the landslide hazard map. The back-propagation training method has been used for the selection of the five different random training sites in order to calculate the factor’s weight and then the landslide hazard indices were computed for each of the five hazard maps. Finally, the landslide hazard maps (five cases) were prepared using GIS tools. Results of the landslides hazard maps have been verified using landslide test locations that were not used during the training phase of the neural network. Our findings of verification results show an accuracy of 69%, 75%, 70%, 83% and 86% for training sites 1, 2, 3, 4 and 5 respectively. GIS data was used to efficiently analyze the large volume of data, and the artificial neural network proved to be an effective tool for landslide hazard analysis. The verification results showed sufficient agreement between the presumptive hazard map and the existing data on landslide areas. [ABSTRACT FROM AUTHOR]