WorldWideScience

Sample records for landslide hazard areas

  1. Landslide Hazards in the Seattle, Washington, Area

    Science.gov (United States)

    Baum, Rex; Harp, Ed; Highland, Lynn

    2007-01-01

    The Seattle, Washington, area is known for its livability and its magnificent natural setting. The city and nearby communities are surrounded by an abundance of rivers and lakes and by the bays of Puget Sound. Two majestic mountain ranges, the Olympics and the Cascades, rim the region. These dramatic natural features are products of dynamic forces-landslides, earthquakes, tsunamis, glaciers, volcanoes, and floods. The same processes that formed this beautiful landscape pose hazards to the ever-growing population of the region. Landslides long have been a major cause of damage and destruction to people and property in the Seattle area.

  2. Landslide hazard assessment in the Collazzone area, Umbria, Central Italy

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    F. Guzzetti

    2006-01-01

    Full Text Available We present the results of the application of a recently proposed model to determine landslide hazard. The model predicts where landslides will occur, how frequently they will occur, and how large they will be in a given area. For the Collazzone area, in the central Italian Apennines, we prepared a multi-temporal inventory map through the interpretation of multiple sets of aerial photographs taken between 1941 and 1997 and field surveys conducted in the period between 1998 and 2004. We then partitioned the 79 square kilometres study area into 894 slope units, and obtained the probability of spatial occurrence of landslides by discriminant analysis of thematic variables, including morphology, lithology, structure and land use. For each slope unit, we computed the expected landslide recurrence by dividing the total number of landslide events inventoried in the terrain unit by the time span of the investigated period. Assuming landslide recurrence was constant, and adopting a Poisson probability model, we determined the exceedance probability of having one or more landslides in each slope unit, for different periods. We obtained the probability of landslide size, a proxy for landslide magnitude, by analysing the frequency-area statistics of landslides, obtained from the multi-temporal inventory map. Lastly, assuming independence, we determined landslide hazard for each slope unit as the joint probability of landslide size, of landslide temporal occurrence, and of landslide spatial occurrence.

  3. Quantify landslide exposure in areas with limited hazard information

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    Pellicani, R.; Spilotro, G.; Van Westen, C. J.

    2012-04-01

    In Daunia region, located in the North-western part of Apulia (Southern Italy), landslides are the main source of damage to properties in the urban centers of the area, involving especially transportation system and the foundation stability of buildings. In the last 50 years, the growing demand for physical development of these unstable minor hillside and mountain centers has produced a very rapid expansion of built-up areas, often with poor planning of urban and territorial infrastructures, and invasion of the agricultural soil. Because of the expansion of the built-up towards not safe areas, human activities such as deforestation or excavation of slopes for road cuts and building sites, etc., have become important triggers for landslide occurrence. In the study area, the probability of occurrence of landslides is very difficult to predict, as well as the expected magnitude of events, due to the limited data availability on past landslide activity. Because the main limitations concern the availability of temporal data on landslides and triggering events (frequency), run-out distance and landslide magnitude, it was not possible to produce a reliable landslide hazard map and, consequently, a risk map. Given these limitations in data availability and details, a qualitative exposure map has been produced and combined with a landslide susceptibility map, both generated using a spatial multi-criteria evaluation (SMCE) procedure in a GIS system, for obtaining the qualitative landslide risk map. The qualitative analysis has been provided the spatial distribution of the exposure level in the study area; this information could be used in a preliminary stage of regional planning. In order to have a better definition of the risk level in the Daunia territory, the quantification of the economic losses at municipal level was carried out. For transforming these information on economic consequences into landslide risk quantification, it was necessary to assume the temporal

  4. Development of the method of landslide hazard assessment on areas of highways in terms of fuzzy information

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    Леонід Іванович Нефьодов

    2014-08-01

    Full Text Available Factors of landslide hazard on areas of highways have been analyzed. The main steps of fuzzy inference method are described. The method of landslide hazard assessment on areas of highways in terms of fuzzy information has been developed. The example of landslide hazard assessment on areas of highways in terms of fuzzy information in Matlab has been provided.

  5. Vulnerability analysis of Landslide hazard area: Case study of South Korea

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    Oh, Chaeyeon; Jun, Kyewon; Kim, Younghwan

    2017-04-01

    Recently such as Landslide and debris flow are occurring over the due to climate changes, frequent sedimentation disaster in mountains area. A scientific analysis of landslide risk areas along with the collection and analysis of a variety of spatial information would be critical for minimizing damage in the event of mountainous disasters such as landslide and debris flow. We carried out a case study of the selected areas at Inje, Gangwon province which suffered from serious landslides due to flash floods by Typhoon Ewiniar in 2006. Landslide and debris flow locations were identified in the study area from interpretation of airborne image and field surveys. We used GIS to construct a spatial information database integrating the data required for a comprehensive analysis of landslide risk areas including geography, hydrology, pedology, and forestry. Furthermore, this study evaluates slope stability of the affected areas using SINMAP(Stability Index Mapping), analyzes spatial data that have high correlation with selected landslide areas using Likelihood ratio. And by applying the Weight of evidence techniques weight values (W+ and W-) which were calculated for each element. We then analyzed the spatial data which were significantly correlated with the landslide occurrence and predicted the mountainous areas with elevated risks of landslide which are vulnerable to disasters, and the hazard map was generated using GIS. Acknowledgments This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT & Future Planning(No.NRF-2014R1A1A3050495).

  6. Landslide and debris-flow hazard analysis and prediction using GIS in Minamata Hougawachi area, Japan

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    Wang, Chunxiang; Esaki, Tetsuro; Xie, Mowen; Qiu, Cheng

    2006-10-01

    On July 20, 2003, following a short duration of heavy rainfall, a debris-flow disaster occurred in the Minamata Hougawachi area, Kumamoto Prefecture, Japan. This disaster was triggered by a landslide. In order to assess the landslide and debris-flow hazard potential of this mountainous region, the study of historic landslides is critical. The objective of the study is to couple 3D slope-stability analysis models and 2D numerical simulation of debris flow within a geographical information systems in order to identity the potential landslide-hazard area. Based on field observations, the failure mechanism of the past landslide is analyzed and the mechanical parameters for 3D slope-stability analysis are calculated from the historic landslide. Then, to locate potential new landslides, the studied area is divided into slope units. Based on 3D slope-stability analysis models and on Monte Carlo simulation, the spots of potential landslides are identified. Finally, we propose a depth-averaged 2D numerical model, in which the debris and water mixture is assumed to be a uniform continuous, incompressible, unsteady Newtonian fluid. The method accurately models the historic debris flow. According to the 2D numerical simulation, the results of the debris-flow model, including the potentially inundated areas, are analyzed, and potentially affected houses, river and road are mapped.

  7. Multiple Landslide-Hazard Scenarios Modeled for the Oakland-Berkeley Area, Northern California

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    Pike, Richard J.; Graymer, Russell W.

    2008-01-01

    With the exception of Los Angeles, perhaps no urban area in the United States is more at risk from landsliding, triggered by either precipitation or earthquake, than the San Francisco Bay region of northern California. By January each year, seasonal winter storms usually bring moisture levels of San Francisco Bay region hillsides to the point of saturation, after which additional heavy rainfall may induce landslides of various types and levels of severity. In addition, movement at any time along one of several active faults in the area may generate an earthquake large enough to trigger landslides. The danger to life and property rises each year as local populations continue to expand and more hillsides are graded for development of residential housing and its supporting infrastructure. The chapters in the text consist of: *Introduction by Russell W. Graymer *Chapter 1 Rainfall Thresholds for Landslide Activity, San Francisco Bay Region, Northern California by Raymond C. Wilson *Chapter 2 Susceptibility to Deep-Seated Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike and Steven Sobieszczyk *Chapter 3 Susceptibility to Shallow Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Kevin M. Schmidt and Steven Sobieszczyk *Chapter 4 Landslide Hazard Modeled for the Cities of Oakland, Piedmont, and Berkeley, Northern California, from a M=7.1 Scenario Earthquake on the Hayward Fault Zone by Scott B. Miles and David K. Keefer *Chapter 5 Synthesis of Landslide-Hazard Scenarios Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike The plates consist of: *Plate 1 Susceptibility to Deep-Seated Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike, Russell W. Graymer, Sebastian Roberts, Naomi B. Kalman, and Steven Sobieszczyk *Plate 2 Susceptibility to Shallow Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Kevin M. Schmidt and Steven

  8. Landslide hazard assessment: recent trends and techniques.

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    Pardeshi, Sudhakar D; Autade, Sumant E; Pardeshi, Suchitra S

    2013-01-01

    Landslide hazard assessment is an important step towards landslide hazard and risk management. There are several methods of Landslide Hazard Zonation (LHZ) viz. heuristic, semi quantitative, quantitative, probabilistic and multi-criteria decision making process. However, no one method is accepted universally for effective assessment of landslide hazards. In recent years, several attempts have been made to apply different methods of LHZ and to compare results in order to find the best suited model. This paper presents the review of researches on landslide hazard mapping published in recent years. The advanced multivariate techniques are proved to be effective in spatial prediction of landslides with high degree of accuracy. Physical process based models also perform well in LHZ mapping even in the areas with poor database. Multi-criteria decision making approach also play significant role in determining relative importance of landslide causative factors in slope instability process. Remote Sensing and Geographical Information System (GIS) are powerful tools to assess landslide hazards and are being used extensively in landslide researches since last decade. Aerial photographs and high resolution satellite data are useful in detection, mapping and monitoring landslide processes. GIS based LHZ models helps not only to map and monitor landslides but also to predict future slope failures. The advancements in Geo-spatial technologies have opened the doors for detailed and accurate assessment of landslide hazards.

  9. Geomorphological analysis of sinkhole and landslide hazard in a karst area of the Venetian Prealps- Italy

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    Tiberi, Valentina

    2010-05-01

    In the pedemountain area of the Asiago Plateau (Venetian Prealps - NE Italy) sinkholes and landslides represent in many cases a complex response to karst processes. Field survey showed that both soil and bedrock are involved, mainly represented by colluvial-alluvial sediments and carbonate rocks. Preliminary observations also reveal the key role of piping and cave-collapse phenomena and the importance of human remedial measures. Within study area, these processes cause damage mainly to agricultural and pasture activities and expose peoples and farm animals to very high hazards. This work provides preliminary results of geomorphological analysis carried out to define sinkhole and landslide hazard and his connections with karst processes. During first phases of the research program, an inventory of interesting phenomena has been elaborated employing GIS technologies. The database has been constantly revised and enriched with new field measurements and thematic maps (i.e. geomorphological, geo-structural, hydrogeological, caves development maps). Specifically, field survey focused on the morphodynamic definition of instability elements allowing to recognize a wide range of morphotypes (mainly with regard to sinkholes) and polygenic morphologies (i.e. mixed sinkholes-landslides configurations). Geomorphological analysis also revealed specific evolutionary trends of instability processes; they could be useful employed to program more effective mitigation strategies.

  10. Hazard analysis in active landslide areas in the State of Veracruz, Mexico

    Science.gov (United States)

    Wilde, Martina; Morales Barrera, Wendy V.; Rodriguez Elizarrarás, Sergio R.; Solleiro Rebolledo, Elizabeth; Sedov, Sergey; Terhorst, Birgit

    2016-04-01

    The year 2013 was characterized by strong storms and hurricanes like the Hurricanes Barbara and Ingrid and the tropical storms Barry and Fernand, which occurred between June and November affecting especially the coastal regions of Mexico. First of all, the State of Veracruz experienced a series of intense rainfalls and as consequences of these events over 780 landslides were registered. More than 45000 people suffered from evacuations. Located on the coast of the Gulf of Mexico, Veracruz has a wide range of altitude differences. The area with the highest elevations reaches from 5675 m.a.s.l. (Pico de Orizaba, the highest mountain of Mexico) to approximately 3000 m.a.s.l. and is characterized by steep slopes and V-shaped valleys. The mountains are part of the Sierra Madre Oriental and the Trans-Mexican Volcanic Belt. Plateaus and rounded hills are typical for the intermediate zones (3000 - 500 m.a.s.l.). The lowest zone (from 500 m.a.s.l. to sea level) is defined by moderate slopes, large rivers and coastal plain areas. The geology shows a variety and complexity of sedimentary and volcanic rocks. The sedimentary formations comprise claystones, siltstones, sandstones and calcareous rocks. Plateaus of basalts and andesites and deposits of ignimbrites are representative for this area. Even though Veracruz is a region highly endangered by landslides, currently there are no susceptibility maps or any other relevant information with high spatial resolution. Because of the lack of high definite information about the landslide hazards in this area, detailed investigations about the conditions (geology, geomorphology, thresholds, etc.) are indispensable. A doctoral grant from the German Academic Exchange Service (DAAD) allowed to carry out investigations in areas affected by large landslides in the year 2013. The selected study sites comprise damaged infrastructures and settlements. With a multi-methodological and interdisciplinary approach different processes and types of

  11. Debris Flow Vulnerability Assessment in Urban Area Associated with Landslide Hazard Map : Application to Busan, Korea

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    Okjeong, Lee; Yoonkyung, Park; Mookwang, Sung; Sangdan, Kim

    2016-04-01

    In this presentation, an urban debris flow disaster vulnerability assessment methodology is suggested with major focus on urban social and economic aspect. The proposed methodology is developed based on the landslide hazard maps that Korean Forest Service has utilized to identify landslide source areas. Frist, debris flows are propagated to urban areas from such source areas by Flow-R model, and then urban vulnerability is evaluated by two categories; physical and socio-economic aspect. The physical vulnerability is associated to buildings that can be broken down by a landslide event directly. This study considers two popular building structure types, reinforced concrete frame and non-reinforced concretes frame, to evaluate the physically-based vulnerability. The socio-economic vulnerability is measured as a function of the resistant levels of the exposed people, the intensity and magnitude of indirect or intangible losses, and preparedness level of the local government. An indicator-based model is established to evaluate the life and indirect loss under urban debris flow disasters as well as the resilience ability against disasters. To illuminate the validity of the suggested methodology, physical and socio-economic vulnerability levels are investigated for Daejeon, Korea using the proposed approach. The results reveal that the higher population density areas under a weaker fiscal condition that are located at the downstream of mountainous areas are more vulnerable than the areas in opposite conditions. Key words: Debris flow disasters, Physical vulnerability, Socio-economic Vulnerability, Urban Acknowledgement This research was supported by a grant(13SCIPS04) from Smart Civil Infrastructure Research Program funded by Ministry of Land, Infrastructure and Transport(MOLIT) of Korea government and Korea Agency for Infrastructure Technology Advancement(KAIA).

  12. Submarine landslides: processes, triggers and hazard prediction.

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    Masson, D G; Harbitz, C B; Wynn, R B; Pedersen, G; Løvholt, F

    2006-08-15

    Huge landslides, mobilizing hundreds to thousands of km(3) of sediment and rock are ubiquitous in submarine settings ranging from the steepest volcanic island slopes to the gentlest muddy slopes of submarine deltas. Here, we summarize current knowledge of such landslides and the problems of assessing their hazard potential. The major hazards related to submarine landslides include destruction of seabed infrastructure, collapse of coastal areas into the sea and landslide-generated tsunamis. Most submarine slopes are inherently stable. Elevated pore pressures (leading to decreased frictional resistance to sliding) and specific weak layers within stratified sequences appear to be the key factors influencing landslide occurrence. Elevated pore pressures can result from normal depositional processes or from transient processes such as earthquake shaking; historical evidence suggests that the majority of large submarine landslides are triggered by earthquakes. Because of their tsunamigenic potential, ocean-island flank collapses and rockslides in fjords have been identified as the most dangerous of all landslide related hazards. Published models of ocean-island landslides mainly examine 'worst-case scenarios' that have a low probability of occurrence. Areas prone to submarine landsliding are relatively easy to identify, but we are still some way from being able to forecast individual events with precision. Monitoring of critical areas where landslides might be imminent and modelling landslide consequences so that appropriate mitigation strategies can be developed would appear to be areas where advances on current practice are possible.

  13. Landslides Hazard Assessment Using Different Approaches

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    Coman Cristina

    2017-06-01

    Full Text Available Romania represents one of Europe’s countries with high landslides occurrence frequency. Landslide hazard maps are designed by considering the interaction of several factors which, by their joint action may affect the equilibrium state of the natural slopes. The aim of this paper is landslides hazard assessment using the methodology provided by the Romanian national legislation and a very largely used statistical method. The final results of these two analyses are quantitative or semi-quantitative landslides hazard maps, created in geographic information system environment. The data base used for this purpose includes: geological and hydrogeological data, digital terrain model, hydrological data, land use, seismic action, anthropic action and an inventory of active landslides. The GIS landslides hazard models were built for the geographical area of the Iasi city, located in the north-east side of Romania.

  14. Hydro-geomorphic connectivity and landslide features extraction to identifying potential threats and hazardous areas

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    Tarolli, Paolo; Fuller, Ian C.; Basso, Federica; Cavalli, Marco; Sofia, Giulia

    2017-04-01

    Hydro-geomorphic connectivity has significantly emerged as a new concept to understand the transfer of surface water and sediment through landscapes. A further scientific challenge is determining how the concept can be used to enable sustainable land and water management. This research proposes an interesting approach to integrating remote sensing techniques, connectivity theory, and geomorphometry based on high-resolution digital terrain model (HR-DTMs) to automatically extract landslides crowns and gully erosion, to determine the different rate of connectivity among the main extracted features and the river network, and thus determine a possible categorization of hazardous areas. The study takes place in two mountainous regions in the Wellington Region (New Zealand). The methodology is a three step approach. Firstly, we performed an automatic detection of the likely landslides crowns through the use of thresholds obtained by the statistical analysis of the variability of landform curvature. After that, the research considered the Connectivity Index to analyse how a complex and rugged topography induces large variations in erosion and sediment delivery in the two catchments. Lastly, the two methods have been integrated to create a unique procedure able to classify the different rate of connectivity among the main features and the river network and thus identifying potential threats and hazardous areas. The methodology is fast, and it can produce a detailed and updated inventory map that could be a key tool for erosional and sediment delivery hazard mitigation. This fast and simple method can be a useful tool to manage emergencies giving priorities to more failure-prone zones. Furthermore, it could be considered to do a preliminary interpretations of geomorphological phenomena and more in general, it could be the base to develop inventory maps. References Cavalli M, Trevisani S, Comiti F, Marchi L. 2013. Geomorphometric assessment of spatial sediment connectivity

  15. COMBINING NEURAL NETWORKS AND GEOSTATISTICS FOR LANDSLIDE HAZARD ASSESSMENT OF SAN SALVADOR METROPOLITAN AREA, EL SALVADOR

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    Ricardo Ríos

    2017-04-01

    Full Text Available This contribution describes the creation of a landslide hazard assessment model for San Salvador, a department in El Salvador. The analysis started with an aerial photointerpretation from Ministry of Environment and Natural Resources of El Salvador (MARN Spanish acronym, where 4792 landslides were identified and georeferenced along with 7 conditioning factors including: geomorphology, geology, rainfall intensity, peak ground acceleration, slope angle, distance to road, and distance to geological fault. Artificial Neural Networks (ANN were utilized to assess the susceptibility to landslides, achieving results where more than 80% of landslide were properly classified using in-sample and out of sample criteria. Logistic regression was used as base of comparison. Logistic regression obtained a lower performance. To complete the analysis we have performed interpolation of the points using the kriging method from geostatistical approach. Finally, the results show that is possible to derive a landslide hazard map, making use of a combination of ANNs and geostatistical techniques, thus the present study can help landslide mitigation in El Salvador.

  16. Landslides hazard mapping integrating remote sensing and geo-morphological data in the Sorrentina Peninsula coastal areas

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    spinetti, claudia; bisson, marina; tolomei, cristiano; colini, laura; galvani, alessandro; moro, marco; saroli, michele; sepe, vincenzo

    2016-04-01

    The densely inhabited Campania region (Southern Italy) is affected by numerous and dangerous landslides. In particular, the coastal area of Sorrentina Peninsula is one of the zones most subjected to two types of landslides: volcanoclastic debris flows and rock fall. The first type occurs during intensive or persistent precipitations and on significant hillslopes where carbonatic bedrock is covered by pyroclastic deposits related to the Somma-Vesuvius and Phlegrean Fields explosive activity. The second type could be triggered by seismic events and occurs in areas where outcropping bedrock with steep slopes (e.g. the cliffs) is subjected to coastal erosion generating cliff instability. In order to improve the landslides hazard zonation in the Sorrentina Peninsula coastal area, we show a multidisciplinary approach to identify the areas more prone to generate such types of landslide. Our approach involves the analyses of ERS (temporal span between 1992-2000), Envisat (2003-2010), and COSMO-SkyMed (2013-2015) SAR data elaborated applying multi-temporal InSAR techniques to obtain the ground displacement maps and the relative displacement time series, integrated by means of GPS data. These maps were used to identify the instability areas and subsequently investigated by field survey, airborne photogeological interpretation and morphometric elaborations derived from airborne Lidar information. In addition, the land cover mapping was obtained using satellite high-medium resolution data. The analysis was performed in a GIS environment allowing to identify the main parameters that influence the slope instability and to obtain the landslide hazard map. finally, the comparison with the landslides historical database provides the different landslides susceptibility degrees classes.

  17. Landslide hazard and land management in high-density urban areas of Campania region, Italy

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    D. Di Martire

    2012-04-01

    Full Text Available Results deriving from a research focused on the interplay between landslides and urban development are presented here, with reference to two densely populated settings located in the Campania region, Italy: the city of Naples and the island of Ischia. Both areas suffer adverse consequences from various types of landslides since at least 2000 yr. Our study evidences that, despite the long history of slope instabilities, the urban evolution, often illegal, disregarded the high landslide propensity of the hillsides; thus, unsafe lands have been occupied, even in recent years, when proper and strict rules have been enacted to downgrade the landslide risk. It is finally argued that future guidelines should not be entirely based upon physical countermeasures against mass movements. On the contrary, national and local authorities should enforce the territorial control, obliging citizens to respect the existing regulations and emphasizing the role of alternative, non-structural solutions.

  18. Landslide hazard and land management in high-density urban areas of Campania region, Italy

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    Di Martire, D.; De Rosa, M.; Pesce, V.; Santangelo, M. A.; Calcaterra, D.

    2012-04-01

    Results deriving from a research focused on the interplay between landslides and urban development are presented here, with reference to two densely populated settings located in the Campania region, Italy: the city of Naples and the island of Ischia. Both areas suffer adverse consequences from various types of landslides since at least 2000 yr. Our study evidences that, despite the long history of slope instabilities, the urban evolution, often illegal, disregarded the high landslide propensity of the hillsides; thus, unsafe lands have been occupied, even in recent years, when proper and strict rules have been enacted to downgrade the landslide risk. It is finally argued that future guidelines should not be entirely based upon physical countermeasures against mass movements. On the contrary, national and local authorities should enforce the territorial control, obliging citizens to respect the existing regulations and emphasizing the role of alternative, non-structural solutions.

  19. Regional landslide hazard assessment based on Distance Evaluation Model

    Institute of Scientific and Technical Information of China (English)

    Jiacun LI; Yan QIN; Jing LI

    2008-01-01

    There are many factors influencing landslide occurrence. The key for landslide control is to confirm the regional landslide hazard factors. The Cameron Highlands of Malaysia was selected as the study area. By bivariate statistical analysis method with GIS software the authors analyzed the relationships among landslides and environmental factors such as lithology, geomorphy, elevation, road and land use. Distance Evaluation Model was developed with Landslide Density(LD). And the assessment of landslide hazard of Cameron Highlands was performed. The result shows that the model has higher prediction precision.

  20. A method for producing digital probabilistic seismic landslide hazard maps; an example from the Los Angeles, California, area

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    Jibson, Randall W.; Harp, Edwin L.; Michael, John A.

    1998-01-01

    The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24,000-scale geologic mapping of the region, (4) extensive data on engineering properties of geologic units, and (5) high-resolution digital elevation models of the topography. All of these data sets have been digitized and rasterized at 10-m grid spacing in the ARC/INFO GIS platform. Combining these data sets in a dynamic model based on Newmark's permanent-deformation (sliding-block) analysis yields estimates of coseismic landslide displacement in each grid cell from the Northridge earthquake. The modeled displacements are then compared with the digital inventory of landslides triggered by the Northridge earthquake to construct a probability curve relating predicted displacement to probability of failure. This probability function can be applied to predict and map the spatial variability in failure probability in any ground-shaking conditions of interest. We anticipate that this mapping procedure will be used to construct seismic landslide hazard maps that will assist in emergency preparedness planning and in making rational decisions regarding development and construction in areas susceptible to seismic slope failure.

  1. Shallow landslide hazard map of Seattle, Washington

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    Harp, Edwin L.; Michael, John A.; Laprade, William T.

    2008-01-01

    Landslides, particularly debris flows, have long been a significant cause of damage and destruction to people and property in the Puget Sound region. Following the years of 1996 and 1997, the Federal Emergency Management Agency designated Seattle as a “Project Impact” city with the goal of encouraging the city to become more disaster resistant to landslides and other natural hazards. A major recommendation of the Project Impact council was that the city and the U.S. Geological Survey collaborate to produce a landslide hazard map. An exceptional data set archived by the city containing more than 100 yr of landslide data from severe storm events allowed comparison of actual landslide locations with those predicted by slope-stability modeling. We used an infinite-slope analysis, which models slope segments as rigid friction blocks, to estimate the susceptibility of slopes to debris flows, which are water-laden slurries that can form from shallow failures of soil and weathered bedrock and can travel at high velocities down steep slopes. Data used for the analysis consisted of a digital slope map derived from recent light detection and ranging (LiDAR) imagery of Seattle, recent digital geologic mapping of the city, and shear-strength test data for the geologic units found in the surrounding area. The combination of these data layers within a geographic information system (GIS) platform allowed us to create a shallow landslide hazard map for Seattle.

  2. Shallow landslide hazard map of Seattle, Washington

    Science.gov (United States)

    Harp, Edwin L.; Michael, John A.; Laprade, William T.

    2008-01-01

    Landslides, particularly debris flows, have long been a significant cause of damage and destruction to people and property in the Puget Sound region. Following the years of 1996 and 1997, the Federal Emergency Management Agency designated Seattle as a “Project Impact” city with the goal of encouraging the city to become more disaster resistant to landslides and other natural hazards. A major recommendation of the Project Impact council was that the city and the U.S. Geological Survey collaborate to produce a landslide hazard map. An exceptional data set archived by the city containing more than 100 yr of landslide data from severe storm events allowed comparison of actual landslide locations with those predicted by slope-stability modeling. We used an infinite-slope analysis, which models slope segments as rigid friction blocks, to estimate the susceptibility of slopes to debris flows, which are water-laden slurries that can form from shallow failures of soil and weathered bedrock and can travel at high velocities down steep slopes. Data used for the analysis consisted of a digital slope map derived from recent light detection and ranging (LiDAR) imagery of Seattle, recent digital geologic mapping of the city, and shear-strength test data for the geologic units found in the surrounding area. The combination of these data layers within a geographic information system (GIS) platform allowed us to create a shallow landslide hazard map for Seattle.

  3. Assessing Landslide Hazard Using Artificial Neural Network

    DEFF Research Database (Denmark)

    Farrokhzad, Farzad; Choobbasti, Asskar Janalizadeh; Barari, Amin

    2011-01-01

    neural network has been developed for use in the stability evaluation of slopes under various geological conditions and engineering requirements. The Artificial neural network model of this research uses slope characteristics as input and leads to the output in form of the probability of failure...... and factor of safety. It can be stated that the trained neural networks are capable of predicting the stability of slopes and safety factor of landslide hazard in study area with an acceptable level of confidence. Landslide hazard analysis and mapping can provide useful information for catastrophic loss...

  4. Landslide Hazards and Risks in Tanon, Sragen, Central Java Province

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    Suwarno Suwarno

    2004-01-01

    Full Text Available The aims of this research are 1 to study and classify the landslide hazard of the study area, and 2 to evaluate the landslide risk of the research area. Field survey and laboratory analysis were used in this research. Terrain characteristic and social economic data were collected by purposive sampling. The structure of terrain unit based on landform unit map, slope map, soil map, and landuse map. Terrain parameters were divided into five classes; that were no hazard, low hazard, medium hazard, high hazard, and highest hazard classes. The risk classes were divided into four classes, that were no risk, low risk, midium risk, and high risk. Based on the landform units, soil type and the land used, the study area can be divided into 27 terrain units. The terrain units are differentiated into the landslide hazard classes and their landslide risk. In the study area there were found 5 classes of landslide hazard, namely 1 no hazard (2 terrain units; 2 low hazard (4 terrain units; 3 medium hazard (8 terrain units; 4 high hazard (11 terrain units; and 5 highest hazard (2 terrain units. Most of the high hazard class are located on hilly terrain units. Distribution of landslide risk in the study area are as follow: 4 terrain units have no risk; 17 terrain units have low risk; 4 terrain units in medium risk; and 2 terrain units have high risk. High risk are mostly located on hilly area with closely populated area.

  5. Geomechanics of Hazardous Landslides

    Institute of Scientific and Technical Information of China (English)

    POISEL Rainer; BEDNARIK Martin; HOLZER Rudolf; LI(S)(C)(A)K Pavel

    2005-01-01

    A catalogue of possible landslide initial failure mechanisms, taking into account the geological setting and the geometry of the slope, the joint structure, the habitus of the rock blocks, as well as the mechanical behaviour of the rocks and of the rock mass (deformation and strength parameters), is presented. Its aim is to give geologists as well as engineers the opportunity to compare phenomena in the field and phenomena belonging to particular mechanisms and to find the mechanism occurring.The presented catalogue of initial landslide mechanisms only comprises the mechanisms having a clearly defined mechanical model that can be divided into empirical relations and into mechanical models,as well as an overview of run out models, which can be divided into empirical relations and into mechanical models.

  6. Monitoring and forecasting local landslide hazard in the area of Longyearbyen, Svalbard - early progress and experiences from the Autumn 2016 events

    Science.gov (United States)

    Wang, Thea; Krøgli, Ingeborg; Boje, Søren; Colleuille, Hervé

    2017-04-01

    Since 2013 the Norwegian Water Resources and Energy Directorate (NVE) has operated a landslide early warning system (LEWS) for mainland Norway. The Svalbard islands, situated 800 km north of the Norwegian mainland, and 1200 km from the North Pole, are not part of the conventional early warning service. However, following the fatal snow avalanche event 19 Dec. 2015 in the settlement of Longyearbyen (78° north latitude), local authorities and the NVE have initiated monitoring of the hydro-meteorological conditions for the area of Longyearbyen, as an extraordinary precaution. Two operational forecasting teams from the NVE; the snow avalanche and the landslide hazard forecasters, perform hazard assessment related to snow avalanches, slush flows, debris flows, shallow slides and local flooding. This abstract will focus on recent experiences made by the landslide hazard team during the autumn 2016 landslide events, caused by a record setting wet and warm summer and autumn of 2016. The general concept of the Norwegian LEWS is based on frequency intervals of extreme hydro-meteorological conditions. This general concept has been transposed to the Longyearbyen area. Although the climate is considerably colder and drier than mainland Norway, experiences so far are positive and seem useful to the local authorities. Initially, the landslide hazard evaluation was intended to consider only slush flow hazard during the snow covered season. However, due to the extraordinary warm and wet summer and autumn 2016, the landslide hazard forecasters unexpectedly had to issue warnings for the local authorities due to increased risk of shallow landslides and debris flows. This was done in close cooperation with the Norwegian Meteorological Institute, who provided weather forecasts from the recently developed weather prediction model, AROME-Arctic. Two examples, from 14-15 Oct and 8-9 Nov 2016, will be given to demonstrate how the landslide hazard assessment for the Longyearbyen area is

  7. Multi scale modelling of landslide hazard and risk assessment in data scarce area - a case study on Dhalai District, Tripura, India

    Science.gov (United States)

    Ghosh, Kapil; De, Sunil Kumar

    2017-04-01

    Successful landslide management plans and policy depends on in-depth knowledge about the hazard and associated risk. Thus, the present research is intended to present an integrated approach involving uses of geospatial technologies for landslide hazard and risk assessment at different scales (site specific to regional level). The landslide hazard map at regional scale (district level) is prepared by using weight-rating based method. To analyze landslide manifestation in the Dhalai district of Tripura different causative factor maps (lithology, road buffer, slope, relative relief, rainfall, fault buffer, landuse/landcover and drainage density) are derived. The analysis revealed that the geological structure and human interference have more influence than other considered factors on the landslide occurrences. The landslide susceptibility zonation map shows that about 1.64 and 16.68% of the total study area is falling under very high and high susceptibility zones respectively. The landslide risk assessment at district level is generated by integrating hazard scouring and resource damage potential scouring (fuzzy membership values) maps. The values of landslide risk matrix are varying within the range of 0.001 to 0.18 and the risk assessment map shows that only 0.45% (10.80 km2) of the district is under very high risk zone, whereas, about 50% pixels of existing road section are under very high to high level of landslide risk. The major part (94.06%) of the district is under very low to low risk zone. Landslide hazard and risk assessment at site specific level have been carried out through intensive field investigation in which it is found that the Ambassa landslide is located within 150 m buffer zone of fault line. Variation of geo-electrical resistivity (2.2Ωm to 31.4Ωm) indicates the complex geological character in this area. Based on the obtained geo-technical result which helps to identify the degree of risk to the existing resource, it is appropriate to

  8. Analysis Landslide Hazard in Banjarmangu Sub District, Banjarnegara District

    Directory of Open Access Journals (Sweden)

    Kuswaji Dwi Priyono

    2016-05-01

    Full Text Available The objective of the research is to find the most suitable soil conservation practice that may be applied to control landslide hazard. In order to achieve that objective, some research steps must be done, are: (1 to identify the land characteristics of the study area that is based on the understanding of some factors that caused and triggered the landslide hazard, i.e.: slope morphology, rocks/soils characteristics, climatic condition, and landuse; (2 to study the types of landslide that occurs in every landforms and determine the area having ideal landslide form; The proposed landslide in this research is the process of masswasting down-slope as a result of the gravitation action on materials being sliding. The landslide types is including creep, slide, slump, and rocks/soils fall. The methods that being applied in the research include field survey methods and the method for determining landslide hazard by using geographic information techniques. Field survey method was intended to characterize the location of every landslide that have been happened in the study area. The results of field survey were applied as materials for determinating the grade of landslide hazard. Scorring and weighting methods of factors that influence landslide was apllied to determine the grade of landslide hazard. Scor and weight were not same for every parameters used for evaluation. The result of field research shows that landslide happen in every landform unit The study area can be devided into 9 landform unit. The landform units are differentiated into the landslide hazard classes, the study area there were found 5 classes of landslide hazard, namely: (1 vary low hazard equal to 16,65% (1 landform unit; (2 low hazard equal to 7,63% (1 landform unit; (3 medium hazard equal to 37,58% (3 landform unit; (4 high hazard equal to 25,41% (2 landforms unit; and (5 highest hazard equal to 12,73% (2 landform unit. Evaluation of landslide hazard shows hat most of study area

  9. Assessing Landslide Hazard Using Artificial Neural Network

    DEFF Research Database (Denmark)

    Farrokhzad, Farzad; Choobbasti, Asskar Janalizadeh; Barari, Amin

    2011-01-01

    neural network has been developed for use in the stability evaluation of slopes under various geological conditions and engineering requirements. The Artificial neural network model of this research uses slope characteristics as input and leads to the output in form of the probability of failure...... and factor of safety. It can be stated that the trained neural networks are capable of predicting the stability of slopes and safety factor of landslide hazard in study area with an acceptable level of confidence. Landslide hazard analysis and mapping can provide useful information for catastrophic loss...... failure" which is main concentration of the current research and "liquefaction failure". Shear failures along shear planes occur when the shear stress along the sliding surfaces exceed the effective shear strength. These slides have been referred to as landslide. An expert system based on artificial...

  10. Landslide Hazard Zonation Mapping and Comparative Analysis of Hazard Zonation Maps

    Institute of Scientific and Technical Information of China (English)

    S. Sarkar; R. Anbalagan

    2008-01-01

    Landslide hazard zonation mapping at regional level of a large area provides a broad trend of landslide potential zones. A macro level landslide hazard zonation for a small area may provide a better insight into the landslide hazards. The main objective of the present work was to carry out macro landslide hazard zonation mapping on 1:50,000 scale in an area where regional level zonation mapping was conducted earlier. In the previous work the regional landslide hazard zonation maps of Srinagar-Rudraprayag area of Garhwal Himalaya in the state of Uttarakhand were prepared using subjective and objective approaches. In the present work the landslide hazard zonation mapping at macro level was carded out in a small area using a Landslide Hazard Evaluation Factor rating scheme. The hazard zonation map produced by using this technique classifies the area into relative hazard classes in which the high hazard zones well correspond with high frequency of landslides. The results of this map when compared with the regional zonation maps prepared earlier show that application of the present technique identified more details of the hazard zones, which are broadly shown in the earlier zonation maps.

  11. Approaches for delineating landslide hazard areas using receiver operating characteristic in an advanced calibrating precision soil erosion model

    Directory of Open Access Journals (Sweden)

    P. T. Ghazvinei

    2015-10-01

    Full Text Available Soil erosion is undesirable natural event that causes land degradation and desertification. Identify the erosion-prone areas is a major component of preventive measures. Recent landslide damages at different regions lead us to develop a model of the erosion susceptibility map using empirical method (RUSLE. A landslide-location map was established by interpreting satellite image. Field observation data was used to validate the intensity of soil erosion. Further, a correlation analysis was conducted to investigate the "Receiver Operating Characteristic" and frequency ratio. Results showed a satisfactory correlation between the prepared RUSLE-based soil erosion map and actual landslide distribution. The proposed model can effectively predict the landslide events in soil-erosion area. Such a reliable predictive model is an effective management facility for the regional landslide forecasting system.

  12. Integration of spatial and temporal data for the definition of different landslide hazard scenarios in the area north of Lisbon (Portugal

    Directory of Open Access Journals (Sweden)

    J. L. Zêzere

    2004-01-01

    Full Text Available A general methodology for the probabilistic evaluation of landslide hazard is applied, taking in account both the landslide susceptibility and the instability triggering factors, mainly rainfall. The method is applied in the Fanhões-Trancão test site (north of Lisbon, Portugal where 100 shallow translational slides were mapped and integrated into a GIS database. For the landslide susceptibility assessment it is assumed that future landslides can be predicted by statistical relationships between past landslides and the spatial data set of the predisposing factors (slope angle, slope aspect, transversal slope profile, lithology, superficial deposits, geomorphology, and land use. Susceptibility is evaluated using algorithms based on statistical/probabilistic analysis (Bayesian model over unique-condition terrain units in a raster basis. The landslide susceptibility map is prepared by sorting all pixels according to the pixel susceptibility value in descending order. In order to validate the results of the susceptibility ana- lysis, the landslide data set is divided in two parts, using a temporal criterion. The first subset is used for obtaining a prediction image and the second subset is compared with the prediction results for validation. The obtained prediction-rate curve is used for the quantitative interpretation of the initial susceptibility map. Landslides in the study area are triggered by rainfall. The integration of triggering information in hazard assessment includes (i the definition of thresholds of rainfall (quantity-duration responsible for past landslide events; (ii the calculation of the relevant return periods; (iii the assumption that the same rainfall patterns (quantity/duration which produced slope instability in the past will produce the same effects in the future (i.e. same types of landslides and same total affected area. The landslide hazard is present as the probability of each pixel to be affected by a slope movement

  13. Remote sensing and GIS-based landslide hazard analysis and cross-validation using multivariate logistic regression model on three test areas in Malaysia

    Science.gov (United States)

    Pradhan, Biswajeet

    2010-05-01

    This paper presents the results of the cross-validation of a multivariate logistic regression model using remote sensing data and GIS for landslide hazard analysis on the Penang, Cameron, and Selangor areas in Malaysia. Landslide locations in the study areas were identified by interpreting aerial photographs and satellite images, supported by field surveys. SPOT 5 and Landsat TM satellite imagery were used to map landcover and vegetation index, respectively. Maps of topography, soil type, lineaments and land cover were constructed from the spatial datasets. Ten factors which influence landslide occurrence, i.e., slope, aspect, curvature, distance from drainage, lithology, distance from lineaments, soil type, landcover, rainfall precipitation, and normalized difference vegetation index (ndvi), were extracted from the spatial database and the logistic regression coefficient of each factor was computed. Then the landslide hazard was analysed using the multivariate logistic regression coefficients derived not only from the data for the respective area but also using the logistic regression coefficients calculated from each of the other two areas (nine hazard maps in all) as a cross-validation of the model. For verification of the model, the results of the analyses were then compared with the field-verified landslide locations. Among the three cases of the application of logistic regression coefficient in the same study area, the case of Selangor based on the Selangor logistic regression coefficients showed the highest accuracy (94%), where as Penang based on the Penang coefficients showed the lowest accuracy (86%). Similarly, among the six cases from the cross application of logistic regression coefficient in other two areas, the case of Selangor based on logistic coefficient of Cameron showed highest (90%) prediction accuracy where as the case of Penang based on the Selangor logistic regression coefficients showed the lowest accuracy (79%). Qualitatively, the cross

  14. Landslide hazard and risk assessment for Ambon city using landslide inventory and geographic information system

    Science.gov (United States)

    Souisa, Matheus; Hendrajaya, Lilik; Handayani, Gunawan

    2016-08-01

    Ambon Island is a volcanic islands arc and included in the territory of the archipelago of small islands are associated with subduction zones that have a degree of high vulnerability to natural disasters, such as erosion and landslides on the slopes of certain conditions. Landslides that occur various in the city of Ambon, usually occurs during the rainy season so that the impacts that occur not only occurs on site but also off site with amount of large sedimentation. This paper presents the application of digital image analysis techniques and tools Geographic Information Systems to describe the degree of landslide hazard and risk areas in locations Ambon City, Moluccas. The cause of the landslide is analyzed through various thematic layers attribute data for the study area. Landslide hazard zonation assessment is done by using historical data, while the landslide risk analysis is done by using the results of landslide hazard assessment and socioeconomic factors by using geospatial models. The risk assessment of landslides can be used to estimate the risk to the population, property and infrastructure. The study results in the form of a map of landslide hazard and the risk of landslides that act to support urban spatial planning based on disaster mitigation.

  15. Probabilistic landslide hazards and risk mapping on Penang Island, Malaysia

    Indian Academy of Sciences (India)

    Saro Lee; Biswajeet Pradhan

    2006-12-01

    This paper deals with landslide hazards and risk analysis of Penang Island, Malaysia using Geographic Information System (GIS) and remote sensing data. Landslide locations in the study area were identified from interpretations of aerial photographs and field surveys. Topographical/ geological data and satellite images were collected and processed using GIS and image processing tools. There are ten landslide inducing parameters which are considered for landslide hazard analysis. These parameters are topographic slope, aspect, curvature and distance from drainage, all derived from the topographic database; geology and distance from lineament, derived from the geologic database; landuse from Landsat satellite images; soil from the soil database; precipitation amount, derived from the rainfall database; and the vegetation index value from SPOT satellite images. Landslide susceptibility was analyzed using landslide-occurrence factors employing the probability–frequency ratio model. The results of the analysis were verified using the landslide location data and compared with the probabilistic model. The accuracy observed was 80.03%. The qualitative landslide hazard analysis was carried out using the frequency ratio model through the map overlay analysis in GIS environment. The accuracy of hazard map was 86.41%. Further, risk analysis was done by studying the landslide hazard map and damageable objects at risk. This information could be used to estimate the risk to population, property and existing infrastructure like transportation network.

  16. Two models for evaluating landslide hazards

    Science.gov (United States)

    Davis, J.C.; Chung, C.-J.; Ohlmacher, G.C.

    2006-01-01

    Two alternative procedures for estimating landslide hazards were evaluated using data on topographic digital elevation models (DEMs) and bedrock lithologies in an area adjacent to the Missouri River in Atchison County, Kansas, USA. The two procedures are based on the likelihood ratio model but utilize different assumptions. The empirical likelihood ratio model is based on non-parametric empirical univariate frequency distribution functions under an assumption of conditional independence while the multivariate logistic discriminant model assumes that likelihood ratios can be expressed in terms of logistic functions. The relative hazards of occurrence of landslides were estimated by an empirical likelihood ratio model and by multivariate logistic discriminant analysis. Predictor variables consisted of grids containing topographic elevations, slope angles, and slope aspects calculated from a 30-m DEM. An integer grid of coded bedrock lithologies taken from digitized geologic maps was also used as a predictor variable. Both statistical models yield relative estimates in the form of the proportion of total map area predicted to already contain or to be the site of future landslides. The stabilities of estimates were checked by cross-validation of results from random subsamples, using each of the two procedures. Cell-by-cell comparisons of hazard maps made by the two models show that the two sets of estimates are virtually identical. This suggests that the empirical likelihood ratio and the logistic discriminant analysis models are robust with respect to the conditional independent assumption and the logistic function assumption, respectively, and that either model can be used successfully to evaluate landslide hazards. ?? 2006.

  17. Regional landslide-hazard assessment for Seattle, Washington, USA

    Science.gov (United States)

    Baum, R.L.; Coe, J.A.; Godt, J.W.; Harp, E.L.; Reid, M.E.; Savage, W.Z.; Schulz, W.H.; Brien, D.L.; Chleborad, A.F.; McKenna, J.P.; Michael, J.A.

    2005-01-01

    Landslides are a widespread, frequent, and costly hazard in Seattle and the Puget Sound area of Washington State, USA. Shallow earth slides triggered by heavy rainfall are the most common type of landslide in the area; many transform into debris flows and cause significant property damage or disrupt transportation. Large rotational and translational slides, though less common, also cause serious property damage. The hundreds of landslides that occurred during the winters of 1995-96 and 1996-97 stimulated renewed interest by Puget Sound communities in identifying landslide-prone areas and taking actions to reduce future landslide losses. Informal partnerships between the U.S. Geological Survey (USGS), the City of Seattle, and private consultants are focusing on the problem of identifying and mapping areas of landslide hazard as well as characterizing temporal aspects of the hazard. We have developed GIS-based methods to map the probability of landslide occurrence as well as empirical rainfall thresholds and physically based methods to forecast times of landslide occurrence. Our methods for mapping landslide hazard zones began with field studies and physically based models to assess relative slope stability, including the effects of material properties, seasonal groundwater levels, and rainfall infiltration. We have analyzed the correlation between historic landslide occurrence and relative slope stability to map the degree of landslide hazard. The City of Seattle is using results of the USGS studies in storm preparedness planning for emergency access and response, planning for development or redevelopment of hillsides, and municipal facility planning and prioritization. Methods we have developed could be applied elsewhere to suit local needs and available data.

  18. Shallow Landslides Hazards in a Changing Climate

    Science.gov (United States)

    Bellugi, D. G.; Perron, J. T.; O'Gorman, P. A.; Milledge, D.

    2015-12-01

    Rainfall-triggered shallow landslides pose hazards to communities, infrastructure, and ecosystems. The magnitude and frequency of extreme precipitation are expected to change under climate warming, but their effects on landslide abundance, size, and spatial distribution are poorly understood. Fractional changes in extreme precipitation can be considerably greater than those in mean precipitation as storm intensity is not constrained by the atmospheric energy budget. Changes in orographic precipitation may also alter the spatial pattern of extreme precipitation. We assess relative changes in extreme precipitation for varying return periods and event durations predicted by regional climate models (RCM) in the USA over the periods 1971-2000 to 2041-2070. We delineate areas where orographic precipitation contributes to changes in extreme precipitation by analyzing topography and local winds associated with these extremes. To verify that RCMs reflect theoretical predictions, we quantify precipitation changes on the lee and windward slopes. We assess impacts of extreme precipitation change on landslide characteristics by applying a search algorithm that predicts landslide abundance, location, and size to a study site in the Oregon Coast Range (OCR) with a 10-year landslide observational record. We test a range of precipitation scenarios, forest management practices, and antecedent moisture conditions. To explore effects of orographic precipitation, we rescale observed precipitation for representative lee and windward locations and find that fractional changes in mean winter precipitation are ~3 times larger on leeward slopes. The fractional changes in intensity are much greater for extreme precipitation than mean precipitation, and they increase with return period. In the Pacific Northwest, leeward increases are ~10% for 2-year events and ~20% for 30-year events. At our study site, a 20% increase in precipitation or antecedent moisture corresponds to a 30-40% increase in

  19. [Relations of landslide and debris flow hazards to environmental factors].

    Science.gov (United States)

    Zhang, Guo-ping; Xu, Jing; Bi, Bao-gui

    2009-03-01

    To clarify the relations of landslide and debris flow hazards to environmental factors is of significance to the prediction and evaluation of landslide and debris flow hazards. Base on the latitudinal and longitudinal information of 18431 landslide and debris flow hazards in China, and the 1 km x 1 km grid data of elevation, elevation difference, slope, slope aspect, vegetation type, and vegetation coverage, this paper analyzed the relations of landslide and debris flow hazards in this country to above-mentioned environmental factors by the analysis method of frequency ratio. The results showed that the landslide and debris flow hazards in China more occurred in lower elevation areas of the first and second transitional zones. When the elevation difference within a 1 km x 1 km grid cell was about 300 m and the slope was around 30 degree, there was the greatest possibility of the occurrence of landslide and debris hazards. Mountain forest land and slope cropland were the two land types the hazards most easily occurred. The occurrence frequency of the hazards was the highest when the vegetation coverage was about 80%-90%.

  20. Landslides and engineering geology of the Seattle, Washington, area

    Science.gov (United States)

    Baum, Rex L.; Godt, Jonathan W.; Highland, Lynn M.

    2008-01-01

    This volume brings together case studies and summary papers describing the application of state-of-the-art engineering geologic methods to landslide hazard analysis for the Seattle, Washington, area. An introductory chapter provides a thorough description of the Quaternary and bedrock geology of Seattle. Nine additional chapters review the history of landslide mapping in Seattle, present case studies of individual landslides, describe the results of spatial assessments of landslide hazard, discuss hydrologic controls on landsliding, and outline an early warning system for rainfall-induced landslides.

  1. Probabilistic, Seismically-Induced Landslide Hazard Mapping of Western Oregon

    Science.gov (United States)

    Olsen, M. J.; Sharifi Mood, M.; Gillins, D. T.; Mahalingam, R.

    2015-12-01

    Earthquake-induced landslides can generate significant damage within urban communities by damaging structures, obstructing lifeline connection routes and utilities, generating various environmental impacts, and possibly resulting in loss of life. Reliable hazard and risk maps are important to assist agencies in efficiently allocating and managing limited resources to prepare for such events. This research presents a new methodology in order to communicate site-specific landslide hazard assessments in a large-scale, regional map. Implementation of the proposed methodology results in seismic-induced landslide hazard maps that depict the probabilities of exceeding landslide displacement thresholds (e.g. 0.1, 0.3, 1.0 and 10 meters). These maps integrate a variety of data sources including: recent landslide inventories, LIDAR and photogrammetric topographic data, geology map, mapped NEHRP site classifications based on available shear wave velocity data in each geologic unit, and USGS probabilistic seismic hazard curves. Soil strength estimates were obtained by evaluating slopes present along landslide scarps and deposits for major geologic units. Code was then developed to integrate these layers to perform a rigid, sliding block analysis to determine the amount and associated probabilities of displacement based on each bin of peak ground acceleration in the seismic hazard curve at each pixel. The methodology was applied to western Oregon, which contains weak, weathered, and often wet soils at steep slopes. Such conditions have a high landslide hazard even without seismic events. A series of landslide hazard maps highlighting the probabilities of exceeding the aforementioned thresholds were generated for the study area. These output maps were then utilized in a performance based design framework enabling them to be analyzed in conjunction with other hazards for fully probabilistic-based hazard evaluation and risk assessment. a) School of Civil and Construction

  2. Application of remote sensed precipitation for landslide hazard assessment models

    Science.gov (United States)

    Kirschbaum, D. B.; Peters-Lidard, C. D.; Adler, R. F.; Kumar, S.; Harrison, K.

    2010-12-01

    The increasing availability of remotely sensed land surface and precipitation information provides new opportunities to improve upon existing landslide hazard assessment methods. This research considers how satellite precipitation information can be applied in two types of landslide hazard assessment frameworks: a global, landslide forecasting framework and a deterministic slope-stability model. Examination of both landslide hazard frameworks points to the need for higher resolution spatial and temporal precipitation inputs to better identify small-scale precipitation forcings that contribute to significant landslide triggering. This research considers how satellite precipitation information may be downscaled to account for local orographic impacts and better resolve peak intensities. Precipitation downscaling is employed in both models to better approximate local rainfall distribution, antecedent conditions, and intensities. Future missions, such as the Global Precipitation Measurement (GPM) mission will provide more frequent and extensive estimates of precipitation at the global scale and have the potential to significantly advance landslide hazard assessment tools. The first landslide forecasting tool, running in near real-time at http://trmm.gsfc.nasa.gov, considers potential landslide activity at the global scale and relies on Tropical Rainfall Measuring Mission (TRMM) precipitation data and surface products to provide a near real-time picture of where landslides may be triggered. Results of the algorithm evaluation indicate that considering higher resolution susceptibility information is a key factor in better resolving potentially hazardous areas. However, success in resolving when landslide activity is probable is closely linked to appropriate characterization of the empirical rainfall intensity-duration thresholds. We test a variety of rainfall thresholds to evaluate algorithmic performance accuracy and determine the optimal set of conditions that

  3. Application of a process-based shallow landslide hazard model over a broad area in Central Italy

    Science.gov (United States)

    Gioia, Eleonora; Speranza, Gabriella; Ferretti, Maurizio; Godt, Jonathan W.; Baum, Rex L.; Marincioni, Fausto

    2015-01-01

    Process-based models are widely used for rainfall-induced shallow landslide forecasting. Previous studies have successfully applied the U.S. Geological Survey’s Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability (TRIGRS) model (Baum et al. 2002) to compute infiltration-driven changes in the hillslopes’ factor of safety on small scales (i.e., tens of square kilometers). Soil data input for such models are difficult to obtain across larger regions. This work describes a novel methodology for the application of TRIGRS over broad areas with relatively uniform hydrogeological properties. The study area is a 550-km2 region in Central Italy covered by post-orogenic Quaternary sediments. Due to the lack of field data, we assigned mechanical and hydrological property values through a statistical analysis based on literature review of soils matching the local lithologies. We calibrated the model using rainfall data from 25 historical rainfall events that triggered landslides. We compared the variation of pressure head and factor of safety with the landslide occurrence to identify the best fitting input conditions. Using calibrated inputs and a soil depth model, we ran TRIGRS for the study area. Receiver operating characteristic (ROC) analysis, comparing the model’s output with a shallow landslide inventory, shows that TRIGRS effectively simulated the instability conditions in the post-orogenic complex during historical rainfall scenarios. The implication of this work is that rainfall-induced landslides over large regions may be predicted by a deterministic model, even where data on geotechnical and hydraulic properties as well as temporal changes in topography or subsurface conditions are not available.

  4. Rainfall-triggered landslides, anthropogenic hazards, and mitigation strategies

    Science.gov (United States)

    Larsen, M.C.

    2008-01-01

    Rainfall-triggered landslides are part of a natural process of hillslope erosion that can result in catastrophic loss of life and extensive property damage in mountainous, densely populated areas. As global population expansion on or near steep hillslopes continues, the human and economic costs associated with landslides will increase. Landslide hazard mitigation strategies generally involve hazard assessment mapping, warning systems, control structures, and regional landslide planning and policy development. To be sustainable, hazard mitigation requires that management of natural resources is closely connected to local economic and social interests. A successful strategy is dependent on a combination of multi-disciplinary scientific and engineering approaches, and the political will to take action at the local community to national scale.

  5. Fostering the uptake of satellite Earth Observation data for landslide hazard understanding: the CEOS Landslide Pilot

    Science.gov (United States)

    Kirschbaum, Dalia; Malet, Jean-Philippe; Roessner, Sigrid

    2017-04-01

    Landslides occur around the world, on every continent, and play an important role in the evolution of landscapes. They also represent a serious hazard in many areas of the world. Despite their importance, it has been estimated that past landslide and landslide potential maps cover less than 1% of the slopes in these landmasses. Systematic information on the type, abundance, and distribution of existing landslides is lacking. Even in countries where landslide information is abundant (e.g. Italy), the vast majority of landslides caused by meteorological (intense or prolonged rainfall, rapid snowmelt) or geophysical (earthquake) triggers go undetected. This paucity of knowledge has consequences on the design of effective remedial and mitigation measures. Systematic use of Earth observation (EO) data and technologies can contribute effectively to detect, map, and monitor landslides, and landslide prone hillsides, in different physiographic and climatic regions. The CEOS (Committee on Earth Observation Satellites) Working Group on Disasters has recently launched a Landslide Pilot (period 2017-2019) with the aim to demonstrate the effective exploitation of satellite EO across the full cycle of landslide disaster risk management, including preparedness, response, and recovery at global, regional, and local scales, with a distinct multi-hazard focus on cascading impacts and risks. The Landslide Pilot is focusing efforts on three objectives: 1. Establish effective practices for merging different Earth Observation data (e.g. optical and radar) to better monitor and map landslide activity over time and space. 2. Demonstrate how landslide products, models, and services can support disaster risk management for multi-hazard and cascading landslide events. 3. Engage and partner with data brokers and end users to understand requirements and user expectations and get feedback through the activities described in objectives 1-2. The Landslide Pilot was endorsed in April 2016 and work

  6. Directions of the US Geological Survey Landslide Hazards Reduction Program

    Science.gov (United States)

    Wieczorek, G.F.

    1993-01-01

    The US Geological Survey (USGS) Landslide Hazards Reduction Program includes studies of landslide process and prediction, landslide susceptibility and risk mapping, landslide recurrence and slope evolution, and research application and technology transfer. Studies of landslide processes have been recently conducted in Virginia, Utah, California, Alaska, and Hawaii, Landslide susceptibility maps provide a very important tool for landslide hazard reduction. The effects of engineering-geologic characteristics of rocks, seismic activity, short and long-term climatic change on landslide recurrence are under study. Detailed measurement of movement and deformation has begun on some active landslides. -from Author

  7. Shallow-landslide hazard map of Seattle, Washington

    Science.gov (United States)

    Harp, Edwin L.; Michael, John A.; Laprade, William T.

    2006-01-01

    Landslides, particularly debris flows, have long been a significant cause of damage and destruction to people and property in the Puget Sound region. Following the years of 1996 and 1997, the Federal Emergency Management Agency (FEMA) designated Seattle as a 'Project Impact' city with the goal of encouraging the city to become more disaster resistant to the effects of landslides and other natural hazards. A major recommendation of the Project Impact council was that the city and the U.S. Geological Survey (USGS) collaborate to produce a landslide hazard map of the city. An exceptional data set archived by the city, containing more than 100 years of landslide data from severe storm events, allowed comparison of actual landslide locations with those predicted by slope-stability modeling. We used an infinite-slope analysis, which models slope segments as rigid friction blocks, to estimate the susceptibility of slopes to shallow landslides which often mobilize into debris flows, water-laden slurries that can form from shallow failures of soil and weathered bedrock, and can travel at high velocities down steep slopes. Data used for analysis consisted of a digital slope map derived from recent Light Detection and Ranging (LIDAR) imagery of Seattle, recent digital geologic mapping, and shear-strength test data for the geologic units in the surrounding area. The combination of these data layers within a Geographic Information System (GIS) platform allowed the preparation of a shallow landslide hazard map for the entire city of Seattle.

  8. Overview Landslide Hazard Assessment of China

    Institute of Scientific and Technical Information of China (English)

    Yin Kunlong; Zhang Guirong; Zhu Liangfeng

    2004-01-01

    In recent years, China has suffered serious geological disasters, most of slope movements due to complex geology, geomorphology, unusual weather conditions, and large-scale land explorations during high speed economic development. According to geological hazard investigations organized by the Ministry of Land and Resources of China, there are 400 towns and more than 10 000 villages under the threatening of those landslide hazards. This paper presents the overview landslide hazard assessment in terms of GIS, which aims to evaluate the overview geohazard potentials, vulnerabilities of lives and land resources, and risks in conterminous China on the scale of 1∶6 000 000. This is the first overview landslide hazard potential map of China.

  9. Landslide hazards and systems analysis: A Central European perspective

    Science.gov (United States)

    Klose, Martin; Damm, Bodo; Kreuzer, Thomas

    2016-04-01

    Part of the problem with assessing landslide hazards is to understand the variable settings in which they occur. There is growing consensus that hazard assessments require integrated approaches that take account of the coupled human-environment system. Here we provide a synthesis of societal exposure and vulnerability to landslide hazards, review innovative approaches to hazard identification, and lay a focus on hazard assessment, while presenting the results of historical case studies and a landslide time series for Germany. The findings add to a growing body of literature that recognizes societal exposure and vulnerability as a complex system of hazard interactions that evolves over time as a function of social change and development. We therefore propose to expand hazard assessments by the framework and concepts of systems analysis (e.g., Liu et al., 2007) Results so far have been promising in ways that illustrate the importance of feedbacks, thresholds, surprises, and time lags in the evolution of landslide hazard and risk. In densely populated areas of Central Europe, landslides often occur in urbanized landscapes or on engineered slopes that had been transformed or created intentionally by human activity, sometimes even centuries ago. The example of Germany enables to correlate the causes and effects of recent landslides with the historical transition of urbanization to urban sprawl, ongoing demographic change, and some chronic problems of industrialized countries today, including ageing infrastructures or rising government debts. In large parts of rural Germany, the combination of ageing infrastructures, population loss, and increasing budget deficits starts to erode historical resilience gains, which brings especially small communities to a tipping point in their efforts to risk reduction. While struggling with budget deficits and demographic change, these communities are required to maintain ageing infrastructures that are particularly vulnerable to

  10. Assessing Landslide Characteristics and Developing a Landslide Potential Hazard Map in Rwanda and Uganda Using NASA Earth Observations

    Science.gov (United States)

    Sinclair, L.; Conner, P.; le Roux, J.; Finley, T.

    2015-12-01

    The International Emergency Disasters Database indicates that a total of 482 people have been killed and another 27,530 have been affected by landslides in Rwanda and Uganda, although the actual numbers are thought to be much higher. Data for individual countries are poorly tracked, but hotspots for devastating landslides occur throughout Rwanda and Uganda due to the local topography and soil type, intense rainfall events, and deforestation. In spite of this, there has been little research in this region that utilizes satellite imagery to estimate areas susceptible to landslides. This project utilized Landsat 8 Operational Land Imager (OLI) data and Google Earth to identify landslides that occurred within the study area. These landslides were then added to SERVIR's Global Landslide Catalog (GLC). Next, Landsat 8 OLI, the Tropical Rainfall Measuring Mission (TRMM), the Global Precipitation Measurement (GPM), and Shuttle Radar Topography Mission Version 2 (SRTM V2) data were used to create a Landslide Susceptibility Map. This was combined with population data from the Socioeconomic Data and Applications Center (SEDAC) to create a Landslide Hazard map. A preliminary assessment of the relative performance of GPM and TRMM in identifying landslide conditions was also performed. The additions to the GLC, the Landslide Susceptibility Map, the Landslide Hazard Map, and the preliminary assessment of satellite rainfall performance will be used by SERVIR and the Regional Centre for Mapping of Resources for Development (RCMRD) for disaster risk management, land use planning, and determining landslide conditions and moisture thresholds.

  11. Integrated multi-parameters Probabilistic Seismic Landslide Hazard Analysis (PSLHA): an innovative approach in the active volcano-tectonic area of Campi Flegrei (Italy)

    Science.gov (United States)

    Caccavale, M.; Matano, F.; Sacchi, M.; Somma, R.; Troise, C.; De Natale, G.

    2013-12-01

    The western coastal sector of Campania region (southern Italy) is characterised by the presence of the active volcano-tectonic area of Campi Flegrei. This area represents a very particular and interesting case-study for a probabilistic seismic hazard analysis (PSHA). The principal seismic source, related with the caldera, is not clearly constrained in the on-shore and off-shore areas. The well-known and monitored phenomenon of bradyseism affecting a large portion of case-study area is not modelled in the standard PSHA approach. From the environmental point of view the presence of very high exposed values in terms of population, buildings, infrastructures and palaces of high archaeological, natural and artistic value, makes this area a strategic natural laboratory to develop new methodologies. Moreover the geomorphological and geo-volcanological features lead to a heterogeneous coastline, made up by both beach and tuff cliffs, rapidly evolving for erosion and landslide (i.e. mainly rock fall and rock slide) phenomena that represent an additional hazard aspect. In the Campi Flegrei the possible occurrence of a moderate/large seismic event represents a serious threat for the inhabitants, for the infrastructures as well as for the environment. In the framework of Italian MON.I.C.A project (sinfrastructural coastlines monitoring) an innovative and dedicated probabilistic methodology has been applied to identify the areas with higher tendency of landslide occurrence due to the seismic effect. Resident population reported the occurrence of some small rock falls along tuff quarry slopes during the main shocks of the 1982-84 bradyseismic events. The PSHA methodology, introduced by Cornell (1968), combines the contributions to the hazard from all potential sources of earthquakes and the average activity rates associated to each seismogenic zone considered. The result of the PSHA is represented by the spatial distribution of a ground-motion (GM) parameter A, such as Peak

  12. Regional landslide hazard assessment in a deep uncertain future

    Science.gov (United States)

    Almeida, Susana; Holcombe, Liz; Pianosi, Francesca; Wagener, Thorsten

    2017-04-01

    Landslides have many negative economic and societal impacts, including the potential for significant loss of life and damage to infrastructure. These risks are likely to be exacerbated in the future by a combination of climatic and socio-economic factors. Climate change, for example, is expected to increase the occurrence of rainfall-triggered landslides, because a warmer atmosphere tends to produce more high intensity rainfall events. Prediction of future changes in rainfall, however, is subject to high levels of uncertainty, making it challenging for decision-makers to identify the areas and populations that are most vulnerable to landslide hazards. In this study, we demonstrate how a physically-based model - the Combined Hydrology and Stability Model (CHASM) - can be used together with Global Sensitivity Analysis (GSA) to explore the underlying factors controlling the spatial distribution of landslide risks across a regional landscape, while also accounting for deep uncertainty around future rainfall conditions. We demonstrate how GSA can used to analyse CHASM which in turn represents the spatial variability of hillslope characteristics in the study region, while accounting for other uncertainties. Results are presented in the form of landslide hazard maps, utilising high-resolution digital elevation datasets for a case study in St Lucia in the Caribbean. Our findings about spatial landslide hazard drivers have important implications for data collection approaches and for long-term decision-making about land management practices.

  13. Regional Landslide Hazard Assessment Considering Potential Climate Change

    Science.gov (United States)

    Almeida, S.; Holcombe, E.; Pianosi, F.; Wagener, T.

    2016-12-01

    Landslides have many negative economic and societal impacts, including the potential for significant loss of life and damage to infrastructure. These risks are likely to be exacerbated in the future by a combination of climatic and socio-economic factors. Climate change, for example, is expected to increase the occurrence of rainfall-triggered landslides, because a warmer atmosphere tends to produce more high intensity rainfall events. Prediction of future changes in rainfall, however, is subject to high levels of uncertainty, making it challenging for decision-makers to identify the areas and populations that are most vulnerable to landslide hazards. In this study, we demonstrate how a physically-based model - the Combined Hydrology and Stability Model (CHASM) - can be used together with Global Sensitivity Analysis (GSA) to explore the underlying factors controlling the spatial distribution of landslide risks across a regional landscape, while also accounting for deep uncertainty around potential future rainfall triggers. We demonstrate how GSA can be used to analyse CHASM which in turn represents the spatial variability of hillslope characteristics in the study region, while accounting for other uncertainties. Results are presented in the form of landslide hazard maps, utilising high-resolution digital elevation datasets for a case study in St Lucia in the Caribbean. Our findings about spatial landslide hazard drivers have important implications for data collection approaches and for long-term decision-making about land management practices.

  14. Assessing Degree of Susceptibility to Landslide Hazard

    Science.gov (United States)

    Sheridan, M. F.; Cordoba, G. A.; Delgado, H.; Stefanescu, R.

    2013-05-01

    The modeling of hazardous mass flows, both dry and water saturated, is currently an area of active research and several stable models have now emerged that have differing degrees of physical and mathematical fidelity. Models based on the early work of Savage and Hutter (1989) assume that very large dense granular flows could be modeled as incompressible continua governed by a Coulomb failure criterion. Based on this concept, Patra et al. (2005) developed a code for dry avalanches, which proposes a thin layer mathematical model similar to shallow-water equations. This concept was implemented in the widely-used TITAN2D program, which integrates the shock-capturing Godunov solution methodology for the equation system. We propose a method to assess the susceptibility of specific locations susceptible to landslides following heavy tephra fall using the TIATN2D code. Successful application requires that the range of several uncertainties must be framed in the selection of model input data: 1) initial conditions, like volume and location of origin of the landslide, 2) bed and internal friction parameters and 3) digital elevation model (DEM) uncertainties. Among the possible ways of coping with these uncertainties, we chose to use Latin Hypercube Sampling (LHS). This statistical technique reduces a computationally intractable problem to such an extent that is it possible to apply it, even with current personal computers. LHS requires that there is only one sample in each row and each column of the sampling matrix, where each row (multi-dimensional) corresponds to each uncertainty. LHS requires less than 10% of the sample runs needed by Monte Carlo approaches to achieve a stable solution. In our application LHS output provides model sampling for 4 input parameters: initial random volumes, UTM location (x and y), and bed friction. We developed a simple Octave script to link the output of LHS with TITAN2D. In this way, TITAN2D can run several times with successively different

  15. 潜在地震滑坡危险区区划方法%Hazards zonation for potential earthquake-induced landslide area

    Institute of Scientific and Technical Information of China (English)

    陈晓利; 冉洪流; 王明明

    2012-01-01

    Earthquake-induced landslide is different from landslide triggered by rainstorms. Compared with landslides caused by rain, landslides induced by earthquake have more wide and dense space distribution and bigger scale, and can cause tremendous loss both to properties and lives. Earthquake-induced landslides usually cannot be prevented by current mitigation measures, thus, it becomes more and more important to develop a useful skill of assessing the hazard of landslides triggered by earthquake for land planning. This paper presents a method for zonation of potential earthquake-induced landslide area based on seismic hazard analysis. The approach takes account of uncertainty about earthquake location, intensity and recurrence, as well as space distribution of seismic peak ground acceleration. The study selects the damaged region in 2008. 5. 12 Wenchuan Earthquake as target area, and divided potential seismic source zone on the studying of geology, tectonics and seismic activity in this region. On the basis of potential seismic source zone division, this paper calculates the seismic peak ground acceleration according to different probability of exceedance of 10Mi, 5% and 2% in 50a using seismic hazard analysis method proposed by Cornell in 1968, and then assesses earthquake-induced landslide hazard of study region with comprehensive indexes model. In this model, the hazard is classified into 4 grades as high, secondary high, secondary low and low, and five indexes are used including seismic peak ground acceleration, slope angle, rock type, and distance to faults and rivers. The result of hazards zonation for potential earthquake-induced landslide in the study area shows that landslide areas in Wenchuan earthquake such as Wenchuan county, Beichuan county. Maoxian county et al, are located at areas of high or secondary high grades. In Leiguzhen area of Beichuan county, where high resolution DEM data is available, the zonation result shows good correlation with reality

  16. The Framework on Multi-Scale Landslide Hazard Evaluation in China

    Science.gov (United States)

    Li, W. Y.; Liu, C.; Gao, J.

    2016-06-01

    Nowadays, Landslide has been one of the most frequent and seriously widespread natural hazards all over the world. How landslides can be monitored and predicted is an urgent research topic of the international landslide research community. Particularly, there is a lack of high quality and updated landslide risk maps and guidelines that can be employed to better mitigate and prevent landslide disasters in many emerging regions, including China. This paper considers national and regional scale, and introduces the framework on combining the empirical and physical models for landslide evaluation. Firstly, landslide susceptibility in national scale is mapped based on empirical model, and indicates the hot-spot areas. Secondly, the physically based model can indicate the process of slope instability in the hot-spot areas. The result proves that the framework is a systematic method on landslide hazard monitoring and early warning.

  17. Deep seated gravitational slope deformations and large landslides: implications on landslide hazard of urban areas and coastal erosion phenomena of Mount Poro headland

    Science.gov (United States)

    Guerricchio, A.; Simeone, V.

    2012-04-01

    Deep seated gravitational slope deformations (DSGSD) characterize the north west and south side of Mount Poro headland, mid Calabria, south Italy, as reported by Guerrichio (2000). This work investigates the DSGSD of Mount Poro headland, in particular the gravitational collapses, occurring between the coast and the western flank of the headland up to an elevation of about 500-600 m AMSL. These collapses seem to be inconsistent with the local lithotypes, made by the substratum of granitic complex of Polia-Copanello. In particular, Ietto and Calcaterra (1988) identified DSGSDs in the area of Zaccanopoli. They assumed these phenomena on the edge between post-uplift gravitative tectonics and deep seated gravitational deformations that were referred to morphologies sub-parallel to the banks of two important local rivers. The local geology comprises severely fractured and sometimes cataclastic granitic rocks. These show deep sub-vertical fracture, bow-shaped and oriented along the direction NNE-SSW in the upstream areas, at an elevation between 500 and 600 m AMSL. For those areas on the right side of the headland, fractures are oriented along NE-SW, N-S and NW-SE, while on the left side of the headland fractures are oriented W-E and NW-SE. In the upstream areas, there are frequent depressed and stretched stripes of land, which are crossed by fractures, which affect granitic masses for a difference of elevation ranging between few tens of meters and one hundred meters. Similar differences of elevation can also be observed either inside the DSGSDs, and the large landslides, like that located immediately upstream Dropia town, where for instance a one hundred meters concave scarp shows. Inside the DSGSDs and inside the topping Pleistocenic deposits, there are frequent twofold terraces, which can be hardly dated. In fact, no fossils are present, and then it is possible to assume their age just on a geomorphologic base. The entire area involved by the DSGSD is few tens of

  18. Landslide hazard zonation assessment using GIS analysis at Golmakan Watershed, northeast of Iran

    Institute of Scientific and Technical Information of China (English)

    Mohammad Reza MANSOURI DANESHVAR; Ali BAGHERZADEH

    2011-01-01

    Landslide hazard is one of the major environmental hazards in geomorphic studies in mountainous areas. For helping the planners in selection of suitable locations to implement development projects, a landslide hazard zonation map has been produced for the Golmakan Watershed as part of Binaloud northern hillsides (northeast of Iran). For this purpose, after preparation of a landslide inventory of the study area, some 15 major parameters were examined for integrated analysis of landslide hazard in the region. The analyses of parameters were done by geo-referencing and lateral model making, satellite imaging of the study area, and spatial analyses by using geographical information system (GIS). The produced factor maps were weighted with analytic hierarchy process (AHP) method and then classified. The study area was classified into four classes of relative landslide hazards:negligible, low, moderate, and high. The final produced map for landslide hazard zonation in Golmakan Watershed revealed that: 1 ) the parameters of land slope and geologic formation have strong correlation (R2 = 0.79 and 0.83,respectively) with the dependent variable landslide hazard (p < 0.05). 2) About 18.8% of the study area has low and negligible hazards to future landslides, while 81.2% of the land area of Golmakan Watershed falls into the high and moderate categories.

  19. New techniques for landslide hazard assessments: opportunities, methodology, and uncertainty

    Science.gov (United States)

    Kirschbaum, D. B.; Peters-Lidard, C. D.; Adler, R. F.; Hong, Y.

    2009-12-01

    An emerging global rainfall-triggered landslide hazard algorithm employs an empirical framework to identify potentially susceptible areas to rainfall-triggered landslides in near real-time. This methodology couples a satellite-derived estimate of cumulative rainfall with a static surface susceptibility map to highlight regions of anticipated landslide activity. While this algorithm represents an important first step in developing a larger-scale landslide prediction framework, there are many uncertainties and assumptions surrounding such a methodology that decreases the functionality and utility of this system. This research seeks to improve upon this initial concept by exploring the potential opportunities and methodological structure needed to advance larger-scale landslide hazard forecasting and make it more of an operational reality. Sensitivity analysis of the surface and rainfall parameters in the preliminary algorithm indicates that surface data resolution and the interdependency of variables must be more appropriately quantified at local and regional scales. Additionally, integrating available surface parameters must be approached in a more theoretical, physically-based manner to better represent the physical processes underlying slope instability and landslide initiation. Several rainfall infiltration and hydrological flow models have been developed to model slope instability at small spatial scales. This research investigates the potential of upscaling a more quantitative hydrological model to larger spatial scales, utilizing satellite and surface data inputs that are obtainable over different geographic regions. Due to the significant role that data and methodological uncertainties play in the effectiveness of landslide hazard assessment outputs, the methodology and data inputs are considered within an ensemble uncertainty framework in order to better resolve the contribution and limitations of model inputs and more effectively communicate the model skill.

  20. Proposed method for hazard mapping of landslide propagation zone

    Science.gov (United States)

    Serbulea, Manole-Stelian; Gogu, Radu; Manoli, Daniel-Marcel; Gaitanaru, Dragos Stefan; Priceputu, Adrian; Andronic, Adrian; Anghel, Alexandra; Liviu Bugea, Adrian; Ungureanu, Constantin; Niculescu, Alexandru

    2013-04-01

    Sustainable development of communities situated in areas with landslide potential requires a fully understanding of the mechanisms that govern the triggering of the phenomenon as well as the propagation of the sliding mass, with catastrophic consequences on the nearby inhabitants and environment. Modern analysis methods for areas affected by the movement of the soil bodies are presented in this work, as well as a new procedure to assess the landslide hazard. Classical soil mechanics offer sufficient numeric models to assess the landslide triggering zone, such as Limit Equilibrium Methods (Fellenius, Janbu, Morgenstern-Price, Bishop, Spencer etc.), blocks model or progressive mobilization models, Lagrange-based finite element method etc. The computation methods for assessing the propagation zones are quite recent and have high computational requirements, thus not being sufficiently used in practice to confirm their feasibility. The proposed procedure aims to assess not only the landslide hazard factor, but also the affected areas, by means of simple mathematical operations. The method can easily be employed in GIS software, without requiring engineering training. The result is obtained by computing the first and second derivative of the digital terrain model (slope and curvature maps). Using the curvature maps, it is shown that one can assess the areas most likely to be affected by the propagation of the sliding masses. The procedure is first applied on a simple theoretical model and then used on a representative section of a high exposure area in Romania. The method is described by comparison with Romanian legislation for risk and vulnerability assessment, which specifies that the landslide hazard is to be assessed, using an average hazard factor Km, obtained from various other factors. Following the employed example, it is observed that using the Km factor there is an inconsistent distribution of the polygonal surfaces corresponding to different landslide

  1. Near real-time landslide hazard assessment using remotely sensed data

    Science.gov (United States)

    Kirschbaum, D.; Stanley, T.; Cappelaere, P. G.; Simmons, J. M. D.

    2015-12-01

    Remote sensing data offers the unique perspective to provide situational awareness of hydrometeorological hazards over large areas in a way that is impossible to achieve with in situ data. Recent work has shown that rainfall-triggered landslides, while typically local hazards that occupy small spatial areas, can be approximated over regional scales in near real-time. By leveraging data from the Global Precipitation Measurement (GPM) mission, topographic data from the Shuttle Radar Topography Mission (SRTM) and other remote and in situ sources, we can represent the conditions for landslide triggering over broad regions. The landslide hazard assessment for situational awareness (LHASA) model integrates satellite precipitation data, a modeled and satellite-based soil moisture product and susceptibility information to improve the characterization of areas that may experience landslide activity at regional and global scales. The goal of LHASA is to better inform decision-making and disaster response agencies on landslide hazards at the regional and global scale. This system outputs straightforward landslide hazard assessment products available in near real-time that can be used to identify landslide-prone areas and the general timing of landslide initiation. This presentation summarizes the results of this modeling framework, discusses the utility of remote sensing products for landslide hazard characterization, and outlines the path forward for this modeling approach.

  2. Effect on Stratum Gradient Frequency Distribution of Landslides in the Three Gorges Area of Northeast Chongqing

    Institute of Scientific and Technical Information of China (English)

    FAN Xiaoyi; QIAO Jianping

    2006-01-01

    The landslide data were calculated in the Three Gorges Area of northeast Chongqing. The results showed that landslide frequency distributions of gradients accorded with the Weibull probability density distribution function. The landslide hazard ratios of gradients were acquired by Weibull accumulation probability distribution function in the different geological units. There was discord between landslide hazard ratio of different geological units and variance of landslide gradient. But they were approximate homology in the strata of Jurassic. The results indicate that the Weibull distribution can quantitatively evaluate the landslide hazard ratios of gradients of the different strata in the Three Gorges Area.

  3. GIS-Based Mapping and Zonation of Landslide Hazards in Xiaojiang Valley of Southwestern China

    Institute of Scientific and Technical Information of China (English)

    Ma Ze-zhong; He Yi-ping; Xie Hong; Cui Peng; Zhong Dun-lun; James S.Gardner

    2003-01-01

    Through the field survey, previous researches and interpretation of aerial photos, a landslide irformation database of Xiaojiang Valley, Yunnan Province was set up based on the remote sensing (RS) and geographic information system (GIS) technologies. In the paper, a quantitative model for the landslide hazard assessment and zoning was presented,in which the potential energy could be obtained on basis of thorough analysis of the potential sliding volume, distance and direction of the landslide body. Taking landslide potential energy as the index of the hazard severity zonation, the study area was divided into severe, heavy, medium and light hazard zones.

  4. GIS-Based Mapping and Zonation of Landslide Hazards in Xiaojiang Valley of Southwestern China

    Institute of Scientific and Technical Information of China (English)

    MaZe-zhong; HeYi-ping; XieHong; CuiPeng; ZhongDun-lun; JamesS.Gardner

    2003-01-01

    Through the field survey, previous researches and interpretation of aerial photos, a landslide information database of Xiaojiang Valley, Yurman Province was set up based on the remote sensing (RS) and geographic information system (GIS) technologies. In the paper, a quantitative model for the landslide hazard assessment and zoning was presented,in which the potential energy could be obtained on basis of thorough analysis of the potential sliding volume, distance and direction of the landslide body. Taking landslide potential energy as the index of the hazard severity zonation, the study area was divided into severe, heavy, medium and light hazard zones.

  5. Investigating applicability of Haeri-Samiee landslide hazard zonation model in Moalemkalayeh watershed, Iran

    Science.gov (United States)

    Beheshtirad, M.; Noormandipour, N.

    2009-04-01

    Identification of regions having potential for landslide occurrence is one of the basic measures in natural resources management which decreases damages causes by these phenomena. For this purpose different landslide hazard zonation models were proposed based on the environmental conditions and goals. In this research applicability of Haeri-samiee Landslide Hazard Zonations Model has been investigated in Moalemkalayeh watershed. For doing this, existing landslides identified and their inventory map was prepared as earthly evidence. Topographical map (1:50000) was divided into 514 cellular network as working unit. Landslide hazard zonation map provided based on H.S. model. We investigated the level of similarity potential hazard classes and figures of the two models with earthly evidence (landslide inventory map) in the SPSS and Minitab environments. Our results showed that there is a significant correlation at the 0.01 level between potential hazard classes and figures with the number of landslides, area of landslide, as well as the multiplication of the number and area of landslides in the H.S. model. Therefore H.S. model is the suitable model for Moalemkalayeh watershed.

  6. A geomorphological approach to the estimation of landslide hazards and risks in Umbria, Central Italy

    Directory of Open Access Journals (Sweden)

    M. Cardinali

    2002-01-01

    Full Text Available We present a geomorphological method to evaluate landslide hazard and risk. The method is based on the recognition of existing and past landslides, on the scrutiny of the local geological and morphological setting, and on the study of site-specific and historical information on past landslide events. For each study area a multi-temporal landslide inventory map has been prepared through the interpretation of various sets of stereoscopic aerial photographs taken over the period 1941–1999, field mapping carried out in the years 2000 and 2001, and the critical review of site-specific investigations completed to solve local instability problems. The multi-temporal landslide map portrays the distribution of the existing and past landslides and their observed changes over a period of about 60 years. Changes in the distribution and pattern of landslides allow one to infer the possible evolution of slopes, the most probable type of failures, and their expected frequency of occurrence and intensity. This information is used to evaluate landslide hazard, and to estimate the associated risk. The methodology is not straightforward and requires experienced geomorphologists, trained in the recognition and analysis of slope processes. Levels of landslide hazard and risk are expressed using an index that conveys, in a simple and compact format, information on the landslide frequency, the landslide intensity, and the likely damage caused by the expected failure. The methodology was tested in 79 towns, villages, and individual dwellings in the Umbria Region of central Italy.

  7. Maps showing seismic landslide hazards in Anchorage, Alaska

    Science.gov (United States)

    Jibson, Randall W.

    2014-01-01

    The devastating landslides that accompanied the great 1964 Alaska earthquake showed that seismically triggered landslides are one of the greatest geologic hazards in Anchorage. Maps quantifying seismic landslide hazards are therefore important for planning, zoning, and emergency-response preparation. The accompanying maps portray seismic landslide hazards for the following conditions: (1) deep, translational landslides, which occur only during great subduction-zone earthquakes that have return periods of =300-900 yr; (2) shallow landslides for a peak ground acceleration (PGA) of 0.69 g, which has a return period of 2,475 yr, or a 2 percent probability of exceedance in 50 yr; and (3) shallow landslides for a PGA of 0.43 g, which has a return period of 475 yr, or a 10 percent probability of exceedance in 50 yr. Deep, translational landslide hazards were delineated based on previous studies of such landslides, with some modifications based on field observations of locations of deep landslides. Shallow-landslide hazards were delineated using a Newmark-type displacement analysis for the two probabilistic ground motions modeled.

  8. Landslide hazard and risk assessment using semi-automatically created landslide inventories

    NARCIS (Netherlands)

    Martha, T.R.; Westen, van C.J.; Kerle, N.; Jetten, V.G.; Kumar, K. V.

    2013-01-01

    Landslide inventories prepared manually from remote sensing data or through field surveys have shown to be useful for preparation of landslide susceptibility and hazard maps. Recent literatures show several studies have been carried out to prepare landslide inventories from satellite data by automat

  9. Landslide hazard and risk assessment using semi-automatically created landslide inventories

    NARCIS (Netherlands)

    Martinez, J.A.; van Westen, C.J.; Kerle, N.; Jetten, V.G.; Kumar, K.V.

    2013-01-01

    Landslide inventories prepared manually from remote sensing data or through field surveys have shown to be useful for preparation of landslide susceptibility and hazard maps. Recent literatures show several studies have been carried out to prepare landslide inventories from satellite data by

  10. PLANNING DECISIONS IN LANDSLIDE AREAS

    Directory of Open Access Journals (Sweden)

    Maria Katarzyna Hełdak

    2016-09-01

    Full Text Available The study discusses the topic of planning decisions taken for the purposes of studies prepared on the municipality level and related to the development of landslide areas in Poland. The aim of the research is to demonstrate the scale of the issue consisting in designating areas at risk of subsidence of soil masses for investment purposes. The research emphasises the essential role of planning documentation in the prevention of investment in such areas. Other vital factors also include the SOPO (Landslide Counteracting System database as well as the staroste, who, in the course of preparation of planning documentation and issuing decisions on development conditions, issues opinions or agrees (depending on the type of document or decision on the planned investment in areas at risk of landslides. The study shows the complexity of the spatial planning and development system in Poland and the significant influence of bodies and institutions on the planned development of areas prone to the subsidence of soil masses.

  11. Effects of land-use changes on landslides in a landslide-prone area (Ardesen, Rize, NE Turkey).

    Science.gov (United States)

    Karsli, F; Atasoy, M; Yalcin, A; Reis, S; Demir, O; Gokceoglu, C

    2009-09-01

    Various natural hazards such as landslides, avalanches, floods and debris flows can result in enormous property damages and human casualties in Eastern Black Sea region of Turkey. Mountainous topographic character and high frequency of heavy rain are the main factors for landslide occurrence in Ardesen, Rize. For this reason, the main target of the present study is to evaluate the landslide hazards using a sequence of historical aerial photographs in Ardesen (Rize), Turkey, by Photogrammetry and Geographical Information System (GIS). Landslide locations in the study area were identified by interpretation of aerial photographs dated in 1973 and 2002, and by field surveys. In the study, the selected factors conditioning landslides are lithology, slope gradient, slope aspect, vegetation cover, land class, climate, rainfall and proximity to roads. These factors were considered as effective on the occurrence of landslides. The areas under landslide threat were analyzed and mapped considering the landslide conditioning factors. Some of the conditioning factors were investigated and estimated by employing visual interpretation of aerial photos and topographic data. The results showed that the slope, lithology, terrain roughness, proximity to roads, and the cover type played important roles on landslide occurrence. The results also showed that degree of landslides was affected by the number of houses constructed in the region. As a consequence, the method employed in the study provides important benefits for landslide hazard mitigation efforts, because a combination of both photogrammetric techniques and GIS is presented.

  12. Landslide susceptibility assessment considering landslide typology. A case study in the area north of Lisbon (Portugal

    Directory of Open Access Journals (Sweden)

    J. L. Zêzere

    2002-01-01

    Full Text Available The aim of the study is to confirm the importance of discriminate different types of slope movements for a better landslide susceptibility evaluation. The study was applied to the sample area of Calhandriz (11.3 km2 in the area North of Lisbon. Sixty shallow translational slides, 23 deeper translational movements and 19 rotational movements were selected for statistical analysis. Landslide susceptibility assessment was achieved using a data-driven approach: the Information Value Method (Yin and Yan, 1988. The method was applied both to the total set of considered landslides and to each type of slope movement, and the obtained success rates for the highest susceptibility classes are higher in the latter case. The different types of landslides are not equally conditioned by the considered instability factors. Information scores are higher for lithology, concordance between slope aspect and dip of the strata, and slope angle, respectively, for rotational movements, translational movements and shallow translational slides. The information value of the variables "presence of artificial cut (roads" and "presence of fluvial channel" is systematically high for the three types of slope movement, pointing out the importance of both anthropogenic influence and bank erosion on slope instability in the study area. Different types of landslides have neither the same magnitude nor equal damaging potential. Furthermore, technical strategies to mitigate landsliding also depend on landslide typology. These are additional reasons to discriminate between different types of slope movements when assessing landslide susceptibility and hazard.

  13. Landslide hazard mapping with selected dominant factors: A study case of Penang Island, Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Tay, Lea Tien; Alkhasawneh, Mutasem Sh.; Ngah, Umi Kalthum [School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Lateh, Habibah [School of Distance Education, Universiti Sains Malaysia, 11600 Penang (Malaysia)

    2015-05-15

    Landslide is one of the destructive natural geohazards in Malaysia. In addition to rainfall as triggering factos for landslide in Malaysia, topographical and geological factors play important role in the landslide susceptibility analysis. Conventional topographic factors such as elevation, slope angle, slope aspect, plan curvature and profile curvature have been considered as landslide causative factors in many research works. However, other topographic factors such as diagonal length, surface area, surface roughness and rugosity have not been considered, especially for the research work in landslide hazard analysis in Malaysia. This paper presents landslide hazard mapping using Frequency Ratio (FR) and the study area is Penang Island of Malaysia. Frequency ratio approach is a variant of probabilistic method that is based on the observed relationships between the distribution of landslides and each landslide-causative factor. Landslide hazard map of Penang Island is produced by considering twenty-two (22) landslide causative factors. Among these twenty-two (22) factors, fourteen (14) factors are topographic factors. They are elevation, slope gradient, slope aspect, plan curvature, profile curvature, general curvature, tangential curvature, longitudinal curvature, cross section curvature, total curvature, diagonal length, surface area, surface roughness and rugosity. These topographic factors are extracted from the digital elevation model of Penang Island. The other eight (8) non-topographic factors considered are land cover, vegetation cover, distance from road, distance from stream, distance from fault line, geology, soil texture and rainfall precipitation. After considering all twenty-two factors for landslide hazard mapping, the analysis is repeated with fourteen dominant factors which are selected from the twenty-two factors. Landslide hazard map was segregated into four categories of risks, i.e. Highly hazardous area, Hazardous area, Moderately hazardous area

  14. Landslide mobility and hazards: implications of the 2014 Oso disaster

    Science.gov (United States)

    Iverson, Richard M.; George, David L.; Allstadt, Kate E.; Reid, Mark E.; Collins, Brian D.; Vallance, James W.; Schilling, Steve P.; Godt, Jonathan W.; Cannon, Charles; Magirl, Christopher S.; Baum, Rex L.; Coe, Jeffrey A.; Schulz, William; Bower, J. Brent

    2015-01-01

    Landslides reflect landscape instability that evolves over meteorological and geological timescales, and they also pose threats to people, property, and the environment. The severity of these threats depends largely on landslide speed and travel distance, which are collectively described as landslide “mobility”. To investigate causes and effects of mobility, we focus on a disastrous landslide that occurred on 22 March 2014 near Oso, Washington, USA, following a long period of abnormally wet weather. The landslide's impacts were severe because its mobility exceeded that of prior historical landslides at the site, and also exceeded that of comparable landslides elsewhere. The ∼8×106 m3 landslide originated on a gently sloping (landslide began after about 50 s of preliminary slope movement, and observational evidence supports the hypothesis that the high mobility of the landslide resulted from liquefaction of water-saturated sediment at its base. Numerical simulation of the event using a newly developed model indicates that liquefaction and high mobility can be attributed to compression- and/or shear-induced sediment contraction that was strongly dependent on initial conditions. An alternative numerical simulation indicates that the landslide would have been far less mobile if its initial porosity and water content had been only slightly lower. Sensitive dependence of landslide mobility on initial conditions has broad implications for assessment of landslide hazards.

  15. Landslides in Nicaragua - Mapping, Inventory, Hazard Assessment, Vulnerability Reduction, and Forecasting Attempts

    Science.gov (United States)

    Dévoli, G.; Strauch, W.; Álvarez, A.; Muñoz, A.; Kjekstad, O.

    2009-04-01

    A successful landslide hazard and risk assessment requires awareness and good understanding of the potential landslide problems within the geographic area involved. However, this requirement is not always met in developing countries where population, scientific community, and the government may not be aware of the landslide threat. The landslide hazard assessment is often neglected or is based on sparse and not well documented technical information. In Nicaragua (Central America), the basic conditions for landslide hazard and risk assessment were first created after the catastrophic landslides triggered by Hurricane Mitch in October 1998. A single landslide took the life of thousands of people at Casita volcano forcing entire communities to be evacuated or relocated and, furthermore, thousands of smaller landslides caused loss of fertile soils and pasture lands, and made serious damages to the infrastructure. Since those events occurred, the public awareness has increased and the country relies now on new local and national governmental laws and policies, on a number of landslide investigations, and on educational and training programs. Dozens of geologists have been capacitated to investigate landslide prone areas, The Instituto Nicaragüense de Estudios Territoriales (INETER), governmental geo-scientific institution, has assumed the responsibility to help land-use planners and public officials to reduce geological hazard losses. They are committed to work cooperatively with national, international, and local agencies, universities and the private sector to provide scientific information and improve public safety through forecasting and warnings. However, in order to provide successful long-term landslide hazard assessment, the institutions must face challenges related to the scarcity and varied quality of available landslide information; collection and access to dispersed data and documents; organization of landslide information in a form that can be easy to

  16. Mapping of hazard from rainfall-triggered landslides in developing countries: Examples from Honduras and Micronesia

    Science.gov (United States)

    Harp, E.L.; Reid, M.E.; McKenna, J.P.; Michael, J.A.

    2009-01-01

    Loss of life and property caused by landslides triggered by extreme rainfall events demonstrates the need for landslide-hazard assessment in developing countries where recovery from such events often exceeds the country's resources. Mapping landslide hazards in developing countries where the need for landslide-hazard mitigation is great but the resources are few is a challenging, but not intractable problem. The minimum requirements for constructing a physically based landslide-hazard map from a landslide-triggering storm, using the simple methods we discuss, are: (1) an accurate mapped landslide inventory, (2) a slope map derived from a digital elevation model (DEM) or topographic map, and (3) material strength properties of the slopes involved. Provided that the landslide distribution from a triggering event can be documented and mapped, it is often possible to glean enough topographic and geologic information from existing databases to produce a reliable map that depicts landslide hazards from an extreme event. Most areas of the world have enough topographic information to provide digital elevation models from which to construct slope maps. In the likely event that engineering properties of slope materials are not available, reasonable estimates can be made with detailed field examination by engineering geologists or geotechnical engineers. Resulting landslide hazard maps can be used as tools to guide relocation and redevelopment, or, more likely, temporary relocation efforts during severe storm events such as hurricanes/typhoons to minimize loss of life and property. We illustrate these methods in two case studies of lethal landslides in developing countries: Tegucigalpa, Honduras (during Hurricane Mitch in 1998) and the Chuuk Islands, Micronesia (during Typhoon Chata'an in 2002).

  17. Landslide hazards mapping using uncertain Naïve Bayesian classification method

    Institute of Scientific and Technical Information of China (English)

    毛伊敏; 张茂省; 王根龙; 孙萍萍

    2015-01-01

    Landslide hazard mapping is a fundamental tool for disaster management activities in Loess terrains. Aiming at major issues with these landslide hazard assessment methods based on Naïve Bayesian classification technique, which is difficult in quantifying those uncertain triggering factors, the main purpose of this work is to evaluate the predictive power of landslide spatial models based on uncertain Naïve Bayesian classification method in Baota district of Yan’an city in Shaanxi province, China. Firstly, thematic maps representing various factors that are related to landslide activity were generated. Secondly, by using field data and GIS techniques, a landslide hazard map was performed. To improve the accuracy of the resulting landslide hazard map, the strategies were designed, which quantified the uncertain triggering factor to design landslide spatial models based on uncertain Naïve Bayesian classification method named NBU algorithm. The accuracies of the area under relative operating characteristics curves (AUC) in NBU and Naïve Bayesian algorithm are 87.29%and 82.47%respectively. Thus, NBU algorithm can be used efficiently for landslide hazard analysis and might be widely used for the prediction of various spatial events based on uncertain classification technique.

  18. Application of remotely sensed data for landslide hazard assessment and forecasting

    Science.gov (United States)

    Bach Kirschbaum, D.; Stanley, T.; Simmons, J. M. D.; Cappelaere, P. G.

    2014-12-01

    Over the past five years, rainfall-triggered landslides have caused over 16,000 fatalities in 65 countries and have resulted in higher annual property losses than any other natural disaster. Yet while hurricanes and earthquakes have global monitoring systems in place to alert disaster response agencies, governments and regional humanitarian groups of potential disasters and related impacts, no such real-time monitoring system exists for rainfall-triggered landslides. This work introduces a new regionally-based system to evaluate landslide hazards in near-real-time through the application of remotely sensed and in situ data. Build upon existing modeling efforts, the landslide hazard assessment and nowcasting system couples satellite precipitation data, a modeled and satellite-based soil moisture product and susceptibility information to improve the characterization of areas that may experience landslide activity. The goal of this system is to better inform decision-making and disaster response agencies on landslide hazards at the regional scale. This system outputs a straightforward, easily-interpreted set of landslide hazard assessment products available in near real-time for the Mesoamerica region that can be used to both identify landslide-prone areas and forecast the potential location and timing of landslide initiation in the future. This research presents the prototype regional model tested over Central America and the Caribbean region using satellite-based information including Tropical Rainfall Measurement Mission (TRMM) near real-time rainfall, modeled soil moisture, topography, soils, road networks and distance to fault zones. These variables are integrated within a simple algorithm framework and model outputs provide a probabilistic representation of potential landslide activity over the region. This presentation summarizes the preliminary results of this modeling framework, discusses the utility of these products for landslide hazard characterization

  19. Landslide size distribution in seismic areas

    Science.gov (United States)

    Valagussa, Andrea; Frattini, Paolo; Crosta, Giovanni B.

    2015-04-01

    In seismic areas, the analysis of the landslides size distribution with the distance from the seismic source is very important for hazard zoning and land planning. From numerical modelling (Bourdeau et al., 2004), it has been observed that the area of the sliding mass tends to increase with the ground-motion amplitude up to a certain threshold input acceleration. This has been also observed empirically for the 1989 Loma Prieta earthquake (Keefer and Manson, 1998) and 1999 Chi Chi earthquake (Khazai and Sitar, 2003). Based on this, it possible to assume that the landslide size decreases with the increase of the distance from the seismic source. In this research, we analysed six earthquakes-induced landslides inventories (Papua New Guinea Earthquake, 1993; Northridge Earthquake, 1994; Niigata-Chuetsu Earthquake 2004; Iwate-Miyagi Nairiku Earthquake, 2008; Wenchuan Earthquake, 2008; Tohoku Earthquake, 2011) with a magnitude ranging between 6.6 and 9.0 Mw. For each earthquake, we first analysed the size of landslides as a function of different factors such as the lithology, the PGA, the relief, the distance from the seismic sources (both fault and epicentre). Then, we analysed the magnitude frequency curves for different distances from the source area and for each lithology. We found that a clear relationship between the size distribution and the distance from the seismic source is not evident, probably due to the combined effect of the different influencing factors and to the non-linear relationship between the ground-motion intensity and the distance from the seismic source.

  20. A method for producing digital probabilistic seismic landslide hazard maps

    Science.gov (United States)

    Jibson, R.W.; Harp, E.L.; Michael, J.A.

    2000-01-01

    The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include: (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24 000-scale geologic mapping of the region, (4) extensive data on engineering properties of geologic units, and (5) high-resolution digital elevation models of the topography. All of these data sets have been digitized and rasterized at 10 m grid spacing using ARC/INFO GIS software on a UNIX computer. Combining these data sets in a dynamic model based on Newmark's permanent-deformation (sliding-block) analysis yields estimates of coseismic landslide displacement in each grid cell from the Northridge earthquake. The modeled displacements are then compared with the digital inventory of landslides triggered by the Northridge earthquake to construct a probability curve relating predicted displacement to probability of failure. This probability function can be applied to predict and map the spatial variability in failure probability in any ground-shaking conditions of interest. We anticipate that this mapping procedure will be used to construct seismic landslide hazard maps that will assist in emergency preparedness planning and in making rational decisions regarding development and construction in areas susceptible to seismic slope failure. ?? 2000 Elsevier Science B.V. All rights reserved.

  1. Landslide hazard prediction in the North-Eastern Apennines (Italy)

    Science.gov (United States)

    Disperati, L.; Guastaldi, E.; Rindinella, A.

    2003-04-01

    In order to assess the landslide hazard nearby the Pergola city (in the Northern-Eastern Apennines, Italy) a ground survey at a scale of 1:10,000 was performed for an extent of about 370 km^2 (Carmignani, 2001), and a GIS of landslides was built. Following statistical analysis allows to assess the correlation among landslide occurrences and causal factors related to the detachment zone (lithology, engineering geology, elevation, slope, aspect, bedding as related with slope face -RBS- and land use). Consequently, considering the morphological, lithological and anthropic characters of current slides, it was agreed to locate possible future landslides in those area actually stable but characterised by similar conditions. Because of that, a geostatistical analysis was performed. Comparing for every landslide the occurence of either single or combined causal factor, the analysis was carried out in grid format. The spatial analysis of the GIS data layers allowed building the unique condition regions (Chung et al., 1995) and creating statistical data on causal factors in relation of landslides. Afterwards, for every region the susceptibility to development of new occurrences (favourability mapping) was calculated by utilising the certainty factor (CF; Chung &Fabbri, 1993). For landslides where crown was identified, the main scarp was considered as occurrence; a buffer around the highest point of landslide was built for all the others (Disperati et al., 2002). Such procedure was applied both for slides (175 occurrences) and flows (464 occurrences). Furthermore, by the application of the procedure to causal factors and their combination, additional information regarding susceptibility to development of new occurrences was calculated. The selection of the most suitable factors combination can be done through the results accuracy assessment in relation of time and/or space (Chung, 1999), by utilising two different hazard information layers, respectively computed from a

  2. Landslide hazard assessment and mitigation measures in Philippine geothermal fields

    Energy Technology Data Exchange (ETDEWEB)

    Leynes, R.D.; Pioquinto, W.P.C.; Caranto, J.A. [PNOC Energy Development Corporation, Fort Bonifacio (Philippines)

    2005-04-01

    Simple, yet reliable, field criteria have been developed and are being used to qualitatively assess slope instability and slope failure potential in Philippine geothermal fields. Based on a hazard assessment classification of slopes along corridor facilities, sites for implementation of engineering measures are selected. Two case studies are presented. In Mindanao field, the ''very high-risk'' classification of an area resulted in the installation of pipe shelters, which subsequently shielded a section of a pipeline from landslides. Follow-up monitoring is also conducted using cheap, locally fabricated tools, such as surface extensometers. This is being done in Leyte field, where a landslide has threatened a transmission line tower. (author)

  3. Uncertainty on shallow landslide hazard assessment: from field data to hazard mapping

    Science.gov (United States)

    Trefolini, Emanuele; Tolo, Silvia; Patelli, Eduardo; Broggi, Matteo; Disperati, Leonardo; Le Tuan, Hai

    2015-04-01

    Shallow landsliding that involve Hillslope Deposits (HD), the surficial soil that cover the bedrock, is an important process of erosion, transport and deposition of sediment along hillslopes. Despite Shallow landslides generally mobilize relatively small volume of material, they represent the most hazardous factor in mountain regions due to their high velocity and the common absence of warning signs. Moreover, increasing urbanization and likely climate change make shallow landslides a source of widespread risk, therefore the interest of scientific community about this process grown in the last three decades. One of the main aims of research projects involved on this topic, is to perform robust shallow landslides hazard assessment for wide areas (regional assessment), in order to support sustainable spatial planning. Currently, three main methodologies may be implemented to assess regional shallow landslides hazard: expert evaluation, probabilistic (or data mining) methods and physical models based methods. The aim of this work is evaluate the uncertainty of shallow landslides hazard assessment based on physical models taking into account spatial variables such as: geotechnical and hydrogeologic parameters as well as hillslope morphometry. To achieve this goal a wide dataset of geotechnical properties (shear strength, permeability, depth and unit weight) of HD was gathered by integrating field survey, in situ and laboratory tests. This spatial database was collected from a study area of about 350 km2 including different bedrock lithotypes and geomorphological features. The uncertainty associated to each step of the hazard assessment process (e.g. field data collection, regionalization of site specific information and numerical modelling of hillslope stability) was carefully characterized. The most appropriate probability density function (PDF) was chosen for each numerical variable and we assessed the uncertainty propagation on HD strength parameters obtained by

  4. Understanding Landslide Tsunami Hazard in Alaska Fjords for Tsunami Inundation Mapping

    Science.gov (United States)

    Suleimani, E.; Hansen, R.

    2007-12-01

    Several communities of the southern coast of Alaska are located in glacial fjords, which are fed by major rivers and creeks draining nearby glaciers and depositing sediments into the bays at a high rate. Sediment accumulation on the steep underwater slopes contributes to the landslide tsunami hazard in these communities. During the Great Alaska Earthquake of 1964, the majority of tsunami-related deaths was due to local landslide tsunamis that occurred almost immediately after the initial shaking, and without any warning signs. In these coastal communities, tsunami potential from tectonic and submarine landslide sources must be evaluated for comprehensive mapping of areas that are at risk for inundation. We are creating tsunami inundation maps for Seward, Alaska, in the scope of the National Tsunami Hazard Mitigation Program. Seward is a community located at the head of Resurrection Bay, which was hit hard by both tectonic and landslide-generated tsunami waves during the 1964 earthquake. The purpose of the project is long- term prediction of potential landslide-generated tsunamis in Resurrection Bay, and public education on landslide-related tsunami hazard. In order to construct tsunami inundation maps for Seward, we use an approach that combines modeling of the historical tsunami events of 1964 in Resurrection Bay for model verification, and assessing the landslide tsunami hazard by simulating hypothetical landslide scenarios and performing sensitivity analysis. To reconstruct the sequence of waves observed at Seward on March 27, 1964, we model tsunami waves caused by superposition of the local landslide-generated tsunamis and the major tectonic tsunami. Next we create hypothetical landslide scenarios that are based on the underwater sediment accumulation areas derived from the bathymetry difference maps. Numerical simulations yield runup heights, extent of maximum inundation for chosen tsunami scenarios, depths of inundation on dry land, and maximum velocity

  5. Landslide Hazard Assessment and Mapping in the Guil Catchment (Queyras, Southern French Alps): From Landslide Inventory to Susceptibility Modelling

    Science.gov (United States)

    Roulleau, Louise; Bétard, François; Carlier, Benoît; Lissak, Candide; Fort, Monique

    2016-04-01

    Landslides are common natural hazards in the Southern French Alps, where they may affect human lives and cause severe damages to infrastructures. As a part of the SAMCO research project dedicated to risk evaluation in mountain areas, this study focuses on the Guil river catchment (317 km2), Queyras, to assess landslide hazard poorly studied until now. In that area, landslides are mainly occasional, low amplitude phenomena, with limited direct impacts when compared to other hazards such as floods or snow avalanches. However, when interacting with floods during extreme rainfall events, landslides may have indirect consequences of greater importance because of strong hillslope-channel connectivity along the Guil River and its tributaries (i.e. positive feedbacks). This specific morphodynamic functioning reinforces the need to have a better understanding of landslide hazards and their spatial distribution at the catchment scale to prevent local population from disasters with multi-hazard origin. The aim of this study is to produce a landslide susceptibility mapping at 1:50 000 scale as a first step towards global estimation of landslide hazard and risk. The three main methodologies used for assessing landslide susceptibility are qualitative (i.e. expert opinion), deterministic (i.e. physics-based models) and statistical methods (i.e. probabilistic models). Due to the rapid development of geographical information systems (GIS) during the last two decades, statistical methods are today widely used because they offer a greater objectivity and reproducibility at large scales. Among them, multivariate analyses are considered as the most robust techniques, especially the logistic regression method commonly used in landslide susceptibility mapping. However, this method like others is strongly dependent on the accuracy of the input data to avoid significant errors in the final results. In particular, a complete and accurate landslide inventory is required before the modelling

  6. GIS Applied to Landslide Hazard Mapping and Evaluation in North-East Wales

    Science.gov (United States)

    Miller, S. A.; Degg, M.

    2009-04-01

    Slope instability is a significant environmental hazard in North-East Wales, responsible for important damage to roads and built-up areas. During the late 1980s and the 1990s, systematic landslide mapping and hazard modelling was completed for a number of landslide prone areas within Great Britain, but no such study has to date been carried out for North Wales. This research reports on the creation of a digital landslide inventory for North-East Wales and the use of a Geographical Information System (GIS) to create the first landslide susceptibility models for the area. The research has resulted in the most comprehensive landslide inventory of North-East Wales completed to date. This was accomplished through a combination of aerial photograph interpretation, field mapping and data collection from secondary sources (e.g. consultancy reports, newspapers), yielding a database that records 430 landslides for the area. This represents a 76% (186 landslides) increase on the number of landslides recorded for the area in the UK national landslides database. The landslides in North-East Wales are almost entirely situated inland, with less than 1% on the coast. Approximately 84% of the landslides occur within drift geology and 16% in solid geology. For the slides of known type, 46% are translational slides, 47% rotational slides, 3% flows, 3% falls and 1% complex failures. The type and distribution of landsliding in the area shows notable differences to that found in areas of similar bedrock geology elsewhere in the UK (e.g. Derbyshire and South Wales). Analysis shows that the main landslide controlling parameters in North-East Wales are: lithology, drift material, slope angle, proximity to known faults (structural weaknesses) and proximity to fluvial channels (undercutting). These factors were weighted statistically based on their estimated contribution to slope instability, and combined to create the landslide susceptibility models using a statistical (multiple logistic

  7. The landslide inventory as the basis of susceptibility and hazard assessment

    Science.gov (United States)

    Copons, Ramon; Linares, Rogelio; Cirés, Jordi; Tallada, Anna

    2010-05-01

    Landslide inventory involves the location, classification, volume, activity and others characteristics of the landslides in an area (Fell et al, 2008). Landslide inventory can includes also the location of lithologies prone to instability, structural conditions and silent witnesses (affected vegetation, damaged buildings, etc). This high quality information about landslides requires the use of images acquired from remote sensing and the field observation. Landslide inventory is the basis for susceptibility, hazard and risk assessment (Fell et al., 2008) because supplies information contrasted on the field. Unfortunately, landslide inventory has limitations so it usually is not totally complete or landslides boundaries mapped are influenced by the techniques used, resources and the ability of the field geologist. These usual errors included in the landslide inventory are difficult to estimate but are crucial to know since can create greater errors on results of susceptibility, hazard and risk assessed by further approaches including heuristic, empirical and deterministic ones. In many cases it is not possible to make an inventory including all the landslides occurred in the past because morphology of older landslides could be extremely eroded, or they are partially or totally covered by younger vents. Moreover, several external factors (like extreme forestation, urbanization or erosion) do not allow their identification or difficult their delimitation. Our work focuses on: (i) the establishment of a procedure for gathering data to complete a landslide inventory, and (ii) the determination of the error included in the landslide inventory whichever the field geologist. These issues are useful for administrations for: (i) undertaking landslide inventories across the country by several geologists, and (ii) managing hazard knowing limitations of the hazard zoning obtained from the landslide inventory. For accomplishing our purposes we have selected an area located about

  8. Landslide tsunami hazard in the Indonesian Sunda Arc

    Directory of Open Access Journals (Sweden)

    S. Brune

    2010-03-01

    Full Text Available The Indonesian archipelago is known for the occurrence of catastrophic earthquake-generated tsunamis along the Sunda Arc. The tsunami hazard associated with submarine landslides however has not been fully addressed. In this paper, we compile the known tsunamigenic events where landslide involvement is certain and summarize the properties of published landslides that were identified with geophysical methods. We depict novel mass movements, found in newly available bathymetry, and determine their key parameters. Using numerical modeling, we compute possible tsunami scenarios. Furthermore, we propose a way of identifying landslide tsunamis using an array of few buoys with bottom pressure units.

  9. Application of a Data Mining Model and It's Cross Application for Landslide Hazard Analysis: a Case Study in Malaysia

    Science.gov (United States)

    Pradhan, Biswajeet; Lee, Saro; Shattri, Mansor

    This paper deals with landslide hazard analysis and cross-application using Geographic Information System (GIS) and remote sensing data for Cameron Highland, Penang Island and Selangor in Malaysia. The aim of this study was to cross-apply and verify a spatial probabilistic model for landslide hazard analysis. Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys. Topographical/geological data and satellite images were collected and processed using GIS and image processing tools. There are ten landslide inducing parameters which are considered for the landslide hazard analysis. These parameters are topographic slope, aspect, curvature and distance from drainage, all derived from the topographic database; geology and distance from lineament, derived from the geologic database; landuse from Landsat satellite images; soil from the soil database; precipitation amount, derived from the rainfall database; and the vegetation index value from SPOT satellite images. These factors were analyzed using an artificial neural network model to generate the landslide hazard map. Each factor's weight was determined by the back-propagation training method. Then the landslide hazard indices were calculated using the trained back-propagation weights, and finally the landslide hazard map was generated using GIS tools. Landslide hazard maps were drawn for these three areas using artificial neural network model derived not only from the data for that area but also using the weight for each parameters, one of the statistical model, calculated from each of the other two areas (nine maps in all) as a cross-check of the validity of the method. For verification, the results of the analyses were compared, in each study area, with actual landslide locations. The verification results showed sufficient agreement between the presumptive hazard map and the existing data on landslide areas.

  10. Earthquake induced landslide hazard field observatory in the Avcilar peninsula

    Science.gov (United States)

    Bigarre, Pascal; Coccia, Stella; Theoleyre, Fiona; Ergintav, Semih; Özel, Oguz; Yalçinkaya, Esref; Lenti, Luca; Martino, Salvatore; Gamba, Paolo; Zucca, Francesco; Moro, Marco

    2015-04-01

    SAR temporal series has been undertaken, providing global but accurate Identification and characterization of gravitational phenomena covering the aera. Evaluation of the resolution and identification of landslide hazard-related features using space multispectral/hyperspectral image data has been realized. Profit has been gained from a vast drilling and geological - geotechnical survey program undertaken by the Istanbul Metropolitan Area, to get important data to complete the geological model of the landslide as well as one deep borehole to set up permanent instrumentation on a quite large slow landslide, fully encircled by a dense building environment. The selected landslide was instrumented in 2014 with a real-time observational system including GPS, rainfall, piezometer and seismic monitoring. Objective of this permanent monitoring system is three folds: first to detect and quantify interaction between seismic motion, rainfall and mass movement, building a database opened to the scientific community in the future, second to help to calibrate dynamic numerical geomechanical simulations intending to study the sensitivity to seismic loading, and last but not least. Last but not least important geophysical field work has been conducted to assess seismic site effects already noticed during the 1999 earthquake .Data, metadata and main results are from now progressively compiled and formatted for appropriate integration in the cloud monitoring infrastructure for data sharing.

  11. Evaluation of the Potential of NASA Multi-satellite Precipitation Analysis in Global Landslide Hazard Assessment

    Science.gov (United States)

    Hong, Yang; Adler, Robert F.; Huffman, George J.

    2007-01-01

    Landslides are one of the most widespread natural hazards on Earth, responsible for thousands of deaths and billions of dollars in property damage every year. In the U.S. alone landslides occur in every state, causing an estimated $2 billion in damage and 25- 50 deaths each year. Annual average loss of life from landslide hazards in Japan is 170. The situation is much worse in developing countries and remote mountainous regions due to lack of financial resources and inadequate disaster management ability. Recently, a landslide buried an entire village on the Philippines Island of Leyte on Feb 17,2006, with at least 1800 reported deaths and only 3 houses left standing of the original 300. Intense storms with high-intensity , long-duration rainfall have great potential to trigger rapidly moving landslides, resulting in casualties and property damage across the world. In recent years, through the availability of remotely sensed datasets, it has become possible to conduct global-scale landslide hazard assessment. This paper evaluates the potential of the real-time NASA TRMM-based Multi-satellite Precipitation Analysis (TMPA) system to advance our understanding of and predictive ability for rainfall-triggered landslides. Early results show that the landslide occurrences are closely associated with the spatial patterns and temporal distribution of rainfall characteristics. Particularly, the number of landslide occurrences and the relative importance of rainfall in triggering landslides rely on the influence of rainfall attributes [e.g. rainfall climatology, antecedent rainfall accumulation, and intensity-duration of rainstorms). TMPA precipitation data are available in both real-time and post-real-time versions, which are useful to assess the location and timing of rainfall-triggered landslide hazards by monitoring landslide-prone areas while receiving heavy rainfall. For the purpose of identifying rainfall-triggered landslides, an empirical global rainfall intensity

  12. Landslide Hazard and Risk Assessment on the Northern Slope of Mt. Changbai, China

    Institute of Scientific and Technical Information of China (English)

    LIU Zhenghua; ZHANG Yanbin; Yoshiharu ISHIKAWA; Hiroyuki NAKAMURA

    2008-01-01

    Landslide hazard and risk assessment on the northern slope of Mt. Changbai,a well-known tourist attraction near the North Korean-Chinese border, are assessed. This study is divided into two parts, namely, landslide hazard zonation and risk assessment. The 1992 Anbalagan and Singh method of landslide hazard zonation (LHZ) was modified and used in this area. In this way, an Associative Analysis Method was used in representative areas to get a measure for controlling factors (slope gradient, relative relief, vegetation, geology, discontinuity development, weak layer thickness and ground water). For the membership degree of factor to slope failure, the middle range of limited values was used to calculate LHZ. Based on an estimation of the potential damage from slope failure,a reasonable risk assessment map was obtained using the relationship of potential damage and probable hazard to aid future planning and prediction and to avert loss of life.

  13. Field-based assessment of landslide hazards resulting from the 2015 Gorkha, Nepal earthquake sequence

    Science.gov (United States)

    Collins, B. D.; Jibson, R.

    2015-12-01

    The M7.8 2015 Gorkha, Nepal earthquake sequence caused thousands of fatalities, destroyed entire villages, and displaced millions of residents. The earthquake sequence also triggered thousands of landslides in the steep Himalayan topography of Nepal and China; these landslides were responsible for hundreds of fatalities and blocked vital roads, trails, and rivers. With the support of USAID's Office of Foreign Disaster Assistance, the U.S. Geological Survey responded to this crisis by providing landslide-hazard expertise to Nepalese agencies and affected villages. Assessments of landslide hazards following earthquakes are essential to identify vulnerable populations and infrastructure, and inform government agencies working on rebuilding and mitigation efforts. However, assessing landslide hazards over an entire earthquake-affected region (in Nepal, estimated to be ~30,000 km2), and in exceedingly steep, inaccessible topography presents a number of logistical challenges. We focused the scope of our assessment by conducting helicopter- and ground-based landslide assessments in 12 priority areas in central Nepal identified a priori from satellite photo interpretation performed in conjunction with an international consortium of remote sensing experts. Our reconnaissance covered 3,200 km of helicopter flight path, extending over an approximate area of 8,000 km2. During our field work, we made 17 site-specific assessments and provided landslide hazard information to both villages and in-country agencies. Upon returning from the field, we compiled our observations and further identified and assessed 74 river-blocking landslide dams, 12% of which formed impoundments larger than 1,000 m2 in surface area. These assessments, along with more than 11 hours of helicopter-based video, and an overview of hazards expected during the 2015 summer monsoon have been publically released (http://dx.doi.org/10.3133/ofr20151142) for use by in-country and international agencies.

  14. Reactivation hazard mapping for ancient landslides in West Belgium

    Directory of Open Access Journals (Sweden)

    O. Dewitte

    2006-01-01

    Full Text Available Several examples in western Europe have shown that, at least for deep-seated rotational slides, reactivation of formerly slipped masses is a more frequent phenomenon than the occurrence of new landslides, therefore representing a higher hazard. We selected a study area comprised of 13 landslides located in the Flemish Ardennes (West Belgium and predicted the hazard related to scarp retreat. The scarp reactivations were identified from the comparison of DTMs produced for 1952 and 1996. Robust results were obtained with the Gamma operator of a fuzzy set approach and a combination of geomorphic, topographic and land use data. We built first a prediction model from the relations linking the 1952–1996 retreat events to the conditioning parameters of 1952. The prediction rate of the resulting susceptibility map is estimated by a cross-validation procedure. We then applied the statistics of this model to the data of 1996 in order to produce a susceptibility map responding to the present-day conditions. Finally, we estimated the conditional probabilities of occurrence of future reactivations for the period 1996–2036.

  15. Mapping landslide processes in the North Tanganyika - Lake Kivu rift zones: towards a regional hazard assessment

    Science.gov (United States)

    Dewitte, Olivier; Monsieurs, Elise; Jacobs, Liesbet; Basimike, Joseph; Delvaux, Damien; Draida, Salah; Hamenyimana, Jean-Baptiste; Havenith, Hans-Balder; Kubwimana, Désiré; Maki Mateso, Jean-Claude; Michellier, Caroline; Nahimana, Louis; Ndayisenga, Aloys; Ngenzebuhoro, Pierre-Claver; Nkurunziza, Pascal; Nshokano, Jean-Robert; Sindayihebura, Bernard; Philippe, Trefois; Turimumahoro, Denis; Kervyn, François

    2015-04-01

    The mountainous environments of the North Tanganyika - Lake Kivu rift zones are part of the West branch of the East African Rift. In this area, natural triggering and environmental factors such as heavy rainfalls, earthquake occurrences and steep topographies favour the concentration of mass movement processes. In addition anthropogenic factors such as rapid land use changes and urban expansion increase the sensibility to slope instability. Until very recently few landslide data was available for the area. Now, through the initiation of several research projects and the setting-up of a methodology for data collection adapted to this data-poor environment, it becomes possible to draw a first regional picture of the landslide hazard. Landslides include a wide range of ground movements such as rock falls, deep failure of slopes and shallow debris flows. Landslides are possibly the most important geohazard in the region in terms of recurring impact on the populations, causing fatalities every year. Many landslides are observed each year in the whole region, and their occurrence is clearly linked to complex topographic, lithological and vegetation signatures coupled with heavy rainfall events, which is the main triggering factor. Here we present the current knowledge of the various slope processes present in these equatorial environments. A particular attention is given to urban areas such as Bukavu and Bujumbura where landslide threat is particularly acute. Results and research perspectives on landslide inventorying, monitoring, and susceptibility and hazard assessment are presented.

  16. Development of models to inform a national Daily Landslide Hazard Assessment for Great Britain

    Science.gov (United States)

    Dijkstra, Tom A.; Reeves, Helen J.; Dashwood, Claire; Pennington, Catherine; Freeborough, Katy; Mackay, Jonathan D.; Uhlemann, Sebastian S.; Chambers, Jonathan E.; Wilkinson, Paul B.

    2015-04-01

    The British Geological Survey (BGS) provides landside hazard information as part of its strategic role. This includes, among others, the issuing of a national Daily Landslide Hazard Assessment (DLHA) one of the hazards assessments issued by the Natural Hazard Partnership. A range of tools are currently under development to further develop reliability and enhance the granularity of these assessments. The BGS has three datasets that support and underpin this research; the National Landslide Database (NLD), the DiGMap mass movement layer and GeoSure. The NLD holds more than 16,500 records of landslides across Great Britain (GB) stored in an Oracle database that is accessible through an ESRI ® ArcGIS interface. DiGMap comprises a digital map layer with outlines of all landslides recorded by field geologists. GeoSure is a BGS product that assesses the potential for ground movement across GB in six layers, one of which is landslide potential. The GeoSure landslide potential layer incorporates information on conditioning factors, such as local geology, geotechnical parameters and topography. These are combined within a GIS to derive a map showing where a landslide may occur under favourable conditions (e.g. persistent wet conditions due to adverse weather). Different types of terrain will be affected by different modes of landsliding and a series of hierarchical landslide domains have been established capturing the spatial consistency of slope deformation response. Each landslide domain represents an area of similar physiographic and geological characteristics which has shaped the style of landsliding (recognising relic, active and potentially active processes). In turn, this enables development of regional thresholds that are relevant to characteristic landslides in these domains. The wet period from summer 2012 into early spring 2013 resulted in a surge of recorded landslides, particularly in SW England and S Wales. Approximations of regional effective precipitation

  17. GIS-Based Spatial Analysis and Modeling for Landslide Hazard Assessment: A Case Study in Upper Minjiang River Basin

    Institute of Scientific and Technical Information of China (English)

    FENG Wenlan; ZHOU Qigang; ZHANG Baolei; ZHOU Wancun; LI Ainong; ZHANG Haizhen; XIAN Wei

    2006-01-01

    By analyzing the topographic features of past landslides since 1980s and the main land-cover types (including change information) in landslide-prone area, modeled spatial distribution of landslide hazard in upper Minjiang River Basin was studied based on spatial analysis of GIS in this paper. Results of GIS analysis showed that landslide occurrence in this region closely related to topographic feature. Most areas with high hazard probability were deep-sheared gorge. Most of them in investigation occurred assembly in areas with elevation lower than 3 000 m, due to fragile topographic conditions and intensive human disturbances. Land-cover type, including its change information, was likely an important environmental factor to trigger landslide. Destroy of vegetation driven by increase of population and its demands augmented the probability of landslide in steep slope.

  18. Hazard assessment of rainfall-induced landsliding in mexico

    Science.gov (United States)

    Alcantara-Ayala, I.

    2004-07-01

    Rainfall-induced landsliding represents a major hazard in Mexico. About 200 municipalities in the states of Puebla, Veracruz and Hidalgo were affected by flooding and mass movement processes that resulted from a tropical depression from the Atlantic Ocean in October 1999. Hundreds of slope failures were triggered by intense precipitation, which in some localities reached 420 mm during a 24-h period. According to official information, 263 people died and 1 475 654 inhabitants were affected by flooding and landsliding. Rainfall event and cycle coefficient defined and the ratios between event and antecedent rainfalls, respectively, and the mean annual rainfall are summed to give a total coefficient. For landslide-triggering rainfalls in the Sierra Norte, values for the total coefficient of 0.8 and 0.4 for beginning and end of the wet season, respectively, appear to be important. In addition, a hazard assessment was carried out through the development of a landslide susceptibility indicator. This was elaborated by using aerial photographs, integrating field observations and the coupling of slope instability analysis within a digital elevation model framework. Field validation indicated that this approach provides a good representation of shallow translational failures; 81% of the observed landslides were satisfactorily predicted as potential unstable zones. Results suggested that this type of DEM-based hazard assessment can be extremely valuable not only after, but also before any landslide-related event, so that disaster preparedness and planning could be adequately structured.

  19. Landslide hazard assessment : LIFE+IMAGINE project methodology and Liguria region use case

    Science.gov (United States)

    Spizzichino, Daniele; Campo, Valentina; Congi, Maria Pia; Cipolloni, Carlo; Delmonaco, Giuseppe; Guerrieri, Luca; Iadanza, Carla; Leoni, Gabriele; Trigila, Alessandro

    2015-04-01

    Scope of the work is to present a methodology developed for analysis of potential impacts in areas prone to landslide hazard in the framework of the EC project LIFE+IMAGINE. The project aims to implement a web services-based infrastructure addressed to environmental analysis, that integrates, in its own architecture, specifications and results from INSPIRE, SEIS and GMES. Existing web services has been customized to provide functionalities for supporting environmental integrated management. The implemented infrastructure has been applied to landslide risk scenarios, developed in selected pilot areas, aiming at: i) application of standard procedures to implement a landslide risk analysis; ii) definition of a procedure for assessment of potential environmental impacts, based on a set of indicators to estimate the different exposed elements with their specific vulnerability in the pilot area. The landslide pilot and related scenario are focused at providing a simplified Landslide Risk Assessment (LRA) through: 1) a landslide inventory derived from available historical and recent databases and maps; 2) landslide susceptibility and hazard maps; 3) assessment of exposure and vulnerability on selected typologies of elements at risk; 4) implementation of a landslide risk scenario for different sets of exposed elements 5) development of a use case; 6) definition of guidelines, best practices and production of thematic maps. The LRA has been implemented in Liguria region, Italy, in two different catchment areas located in the Cinque Terre National Park, characterized by a high landslide susceptibility and low resilience. The landslide risk impact analysis has been calibrated taking into account the socio-economic damage caused by landslides triggered by the October 2011 meteorological event. During this event, over 600 landslides were triggered in the selected pilot area. Most of landslides affected the diffuse system of anthropogenic terraces and caused the direct

  20. Communicating landslide hazard and risk through global catalogs and a forecasting framework

    Science.gov (United States)

    Kirschbaum, D. B.; Adler, D.; Adler, R. F.

    2010-12-01

    over estimation of potential landslide activity areas, are geographically variable and depend on the spatial resolution of the landslide susceptibility information as well as the rainfall information and thresholds used to identify triggering conditions in time. The ability to accurately evaluate the algorithm’s performance is closely linked to the availability and accuracy of landslide event information in the global landslide catalog. Near real-time communication of susceptible landslide areas from the landslide algorithm framework is controlled by the availability and accuracy of satellite-based precipitation information. Current missions such as the Tropical Rainfall Measuring Mission (TRMM) as well as future missions such as the Global Precipitation Measurement (GPM) mission provide critical inputs to near real-time hazard assessment and numerical weather forecasts. Synthesizing landslide report information and the landslide hazard forecasting framework provides the unique opportunity to evaluate and communicate landslide hazard and risk globally to a broad audience, including the scientific community, public, governments, and response organizations.

  1. Landslide hazard in Bukavu (DR Congo): a geomorphological assessment in a data-poor context

    Science.gov (United States)

    Dewitte, Olivier; Mugaruka Bibentyo, Toussaint; Kulimushi Matabaro, Sylvain; Balegamire, Clarisse; Basimike, Joseph; Delvaux, Damien; Dille, Antoine; Ganza Bamulezi, Gloire; Jacobs, Liesbet; Michellier, Caroline; Monsieurs, Elise; Mugisho Birhenjira, Espoir; Nshokano, Jean-Robert; Nzolang, Charles; Kervyn, François

    2017-04-01

    Many cities in the Global South are known for facing an important increase in their population size. Many of them are then struggling with the sprawl of new settlements and very often urban planning and sustainable management policies are limited, if not non-existent. When those cities are set in landslide-prone environments, this situation is even more problematic. Despite these environmental constrains, landslide hazard assessments relevant for landscape planning remain rare. The objective of this research is to assess the landslide hazard in Bukavu, a city in DR Congo that is facing such a situation. We used a geomorphological approach (adapted from Cardinali et al., 2002) taking into account the data-poor context and the impact of anthropogenic activities. First, we built a multi-temporal historical inventory for a period of 60 years. A total of 151 landslides were mapped (largest landslide 1.5 km2). Their cumulative areas cover 29% of the urban territory and several types of processes are identified. Changes in the distribution and pattern of landslides allowed then to infer the possible evolution of the slopes, the most probable type of failures, and their expected frequency of occurrence and intensity. Despite this comprehensive inventory, hazard linked to the occurrence of new large deep-seated slides cannot be assessed due a scarcity of reliable data on the environmental factors controlling their occurrence. In addition, age estimation of the occurrence of some of the largest landslides refers to periods at the beginning of the Holocene where climatic and seismic conditions were probably different. Therefore, based on the inventory, we propose four hazard scenarios that coincide with today's environment. Hazard assessment was done for (1) reactivation of deep-seated slides, (2) occurrence of new small shallow slides, (3) rock falls, and (4) movements within existing landslides. Based on these assessments, we produced four hazard maps that indicate the

  2. The 3D Elevation Program—Landslide recognition, hazard assessment, and mitigation support

    Science.gov (United States)

    Lukas, Vicki; Carswell, Jr., William J.

    2017-01-27

    The U.S. Geological Survey (USGS) Landslide Hazards Program conducts landslide hazard assessments, pursues landslide investigations and forecasts, provides technical assistance to respond to landslide emergencies, and engages in outreach. All of these activities benefit from the availability of high-resolution, three-dimensional (3D) elevation information in the form of light detection and ranging (lidar) data and interferometric synthetic aperture radar (IfSAR) data. Research on landslide processes addresses critical questions of where and when landslides are likely to occur as well as their size, speed, and effects. This understanding informs the development of methods and tools for hazard assessment and situational awareness used to guide efforts to avoid or mitigate landslide impacts. Such research is essential for the USGS to provide improved information on landslide potential associated with severe storms, earthquakes, volcanic activity, coastal wave erosion, and wildfire burn areas.Decisionmakers in government and the private sector increasingly depend on information the USGS provides before, during, and following disasters so that communities can live, work, travel, and build safely. The USGS 3D Elevation Program (3DEP) provides the programmatic infrastructure to generate and supply lidar-derived superior terrain data to address landslide applications and a wide range of other urgent needs nationwide. By providing data to users, 3DEP reduces users’ costs and risks and allows them to concentrate on their mission objectives. 3DEP includes (1) data acquisition partnerships that leverage funding, (2) contracts with experienced private mapping firms, (3) technical expertise, lidar data standards, and specifications, and (4) most important, public access to high-quality 3D elevation data.

  3. Hazard mapping related to structurally controlled landslides in Southern Leyte, Philippines

    Science.gov (United States)

    Luzon, Paul Kenneth; Montalbo, Kristina; Galang, Jam; Sabado, Jasmine May; Escape, Carmille Marie; Felix, Raquel; Mahar Francisco Lagmay, Alfredo

    2016-04-01

    The 2006 Guinsaugon landslide in Saint Bernard, Southern Leyte, is one of the largest known landslides in the Philippines in recent history. It consists of a 15-20 million m3 rockslide-debris avalanche from an approximately 675 m high mountain weakened by continuous movement of the Philippine Fault. The catastrophic Guinsaugon landslide killed 1221 people and displaced 19 000 residents over its 4.5 km path. To investigate the present-day morphology of the scar and potential failure that may occur, analysis of a 5 m resolution InSAR-derived digital elevation model was conducted using Coltop3D and Matterocking software, leading to the generation of a landslide hazard map for the province of Southern Leyte in central Philippines. The dip and dip direction of discontinuity sets that contribute to gravitational failure in mountainous areas of the province were identified and measured using a lower Schmidt-Lambert color scheme. After measurement of the morpho-structural orientations, potential sites of failure were analyzed. Conefall was then utilized to compute the extent of rock mass runout. Results of the analysis show instability in the scarp area of the 2006 Guinsaugon landslide and in adjacent slopes because of the presence of steep discontinuities that range from 45 to 60°. Apart from the 2006 Guinsaugon landslide site, runout models simulated farther rock mass extent in its adjacent slopes, revealing a high potential for fatal landslides to happen in the municipality of Saint Bernard. Concerned agencies may use maps produced in the same manner as this study to identify possible sites where structurally controlled landslides can occur. In a country like the Philippines, where fractures and faults are common, this type of simulated hazard maps would be useful for disaster prevention and facilitate disaster risk reduction efforts for landslide-susceptible areas.

  4. Assessing landslide exposure in areas with limited landslide information

    NARCIS (Netherlands)

    Pellicani, R.; van Westen, C.J.; Spilotro, G.

    2014-01-01

    Landslide risk assessment is often a difficult task due to the lack of temporal data on landslides and triggering events (frequency), run-out distance, landslide magnitude and vulnerability. The probability of occurrence of landslides is often very difficult to predict, as well as the expected

  5. Combining heuristic and statistical techniques in landslide hazard assessments

    Science.gov (United States)

    Cepeda, Jose; Schwendtner, Barbara; Quan, Byron; Nadim, Farrokh; Diaz, Manuel; Molina, Giovanni

    2014-05-01

    As a contribution to the Global Assessment Report 2013 - GAR2013, coordinated by the United Nations International Strategy for Disaster Reduction - UNISDR, a drill-down exercise for landslide hazard assessment was carried out by entering the results of both heuristic and statistical techniques into a new but simple combination rule. The data available for this evaluation included landslide inventories, both historical and event-based. In addition to the application of a heuristic method used in the previous editions of GAR, the availability of inventories motivated the use of statistical methods. The heuristic technique is largely based on the Mora & Vahrson method, which estimates hazard as the product of susceptibility and triggering factors, where classes are weighted based on expert judgment and experience. Two statistical methods were also applied: the landslide index method, which estimates weights of the classes for the susceptibility and triggering factors based on the evidence provided by the density of landslides in each class of the factors; and the weights of evidence method, which extends the previous technique to include both positive and negative evidence of landslide occurrence in the estimation of weights for the classes. One key aspect during the hazard evaluation was the decision on the methodology to be chosen for the final assessment. Instead of opting for a single methodology, it was decided to combine the results of the three implemented techniques using a combination rule based on a normalization of the results of each method. The hazard evaluation was performed for both earthquake- and rainfall-induced landslides. The country chosen for the drill-down exercise was El Salvador. The results indicate that highest hazard levels are concentrated along the central volcanic chain and at the centre of the northern mountains.

  6. Landslide Hazard Zonation Along NH-39 From Kangpokpi To Mao, Manipur, India

    Directory of Open Access Journals (Sweden)

    TH. DEVALA DEVI

    2011-06-01

    Full Text Available Due to the prevailing high rainfall and complex nature of terrain, hilly areas of Manipur are vulnerable to instability and mass wasting which have been aggravated by rapid pace of anthropogenic activities and high seismicity. To categorize the land surface into areas and arrange them according to degree of actual or potential hazard from landslide or other mass movements on slopes, an effort is made to prepare landslide hazard zonation map along NH-39 from Kangpokpi to Mao, covering an area of 650km2. Based on the hazardousness to landslide the study area has been divided into four different zones. The major part of the study area about 380km2 (58% falls under the category of high risk zone, followed by moderate risk zone covering an area of 152km2, low risk zone (115 km2, and very high hazard zone (3 km2. Such zonation maps are useful for identifying and delineating unstable hazard prone areas so that suitable mitigative measures can be adopted to minimize the hazards. It also helps planners to choose the favorable sites for developmental schemes like road and building constructions.

  7. Rapid field-based landslide hazard assessment in response to post-earthquake emergency

    Science.gov (United States)

    Frattini, Paolo; Gambini, Stefano; Cancelliere, Giorgio

    2016-04-01

    On April 25, 2015 a Mw 7.8 earthquake occurred 80 km to the northwest of Kathmandu (Nepal). The largest aftershock, occurred on May 12, 2015, was the Mw 7.3 Nepal earthquake (SE of Zham, China), 80 km to the east of Kathmandu. . The earthquakes killed ~9000 people and severely damaged a 10,000 sqkm region in Nepal and neighboring countries. Several thousands of landslides have been triggered during the event, causing widespread damages to mountain villages and the evacuation of thousands of people. Rasuwa was one of the most damaged districts. This contribution describes landslide hazard analysis of the Saramthali, Yarsa and Bhorle VDCs (122 km2, Rasuwa district). Hazard is expressed in terms of qualitative classes (low, medium, high), through a simple matrix approach that combines frequency classes and magnitude classes. The hazard analysis is based primarily on the experience gained during a field survey conducted in September 2014. During the survey, local knowledge has been systematically exploited through interviews with local people that have experienced the earthquake and the coseismic landslides. People helped us to recognize fractures and active deformations, and allowed to reconstruct a correct chronicle of landslide events, in order to assign the landslide events to the first shock, the second shock, or the post-earthquake 2015 monsoon. The field experience was complemented with a standard analysis of the relationship between potential controlling factors and the distribution of landslides reported in Kargel et al (2016). This analysis allowed recognizing the most important controlling factor. This information was integrated with the field observations to verify the mapped units and to complete the mapping in area not accessible for field activity. Finally, the work was completed with the analysis and the use of a detailed landslide inventory produced by the University of Milano Bicocca that covers most of the area affected by coseismic landslides in

  8. Hazard Mapping of Structurally Controlled Landslide in Southern Leyte, Philippines Using High Resolution Digital Elevation Model

    Science.gov (United States)

    Luzon, Paul Kenneth; Rochelle Montalbo, Kristina; Mahar Francisco Lagmay, Alfredo

    2014-05-01

    The 2006 Guinsaugon landslide in St. Bernard, Southern Leyte is the largest known mass movement of soil in the Philippines. It consisted of a 15 million m3 rockslide-debris avalanche from an approximately 700 m high escarpment produced by continuous movement of the Philippine fault at approximately 2.5 cm/year. The landslide was preceded by continuous heavy rainfall totaling 571.2 mm from February 8 to 12, 2006. The catastrophic landslide killed more than 1,000 people and displaced 19,000 residents over its 6,400 km path. To investigate the present-day morphology of the scar and potential failure that may occur, an analysis of a high-resolution digital elevation model (10 m resolution Synthetic Aperture Radar images in 2013) was conducted, leading to the generation of a structurally controlled landslide hazard map of the area. Discontinuity sets that could contribute to any failure mechanism were identified using Coltop 3D software which uses a unique lower Schmidt-Lambert color scheme for any given dip and dip direction. Thus, finding main morpho-structural orientations became easier. Matterocking, a software designed for structural analysis, was used to generate possible planes that could slide due to the identified discontinuity sets. Conefall was then utilized to compute the extent to which the rock mass will run out. The results showed potential instabilities in the scarp area of the 2006 Guinsaguon landslide and in adjacent slopes because of the presence of steep discontinuities that range from 45-60°. Apart from the 2006 Guinsaugon potential landslides, conefall simulation generated farther rock mass extent in adjacent slopes. In conclusion, there is a high probability of landslides in the municipality of St. Bernard Leyte, where the 2006 Guinsaugon Landslide occurred. Concerned agencies may use maps produced from this study for disaster preparedness and to facilitate long-term recovery planning for hazardous areas.

  9. Geomorphological features and monitoring of a large and complex landslide near Avigliano urban area (South Italy

    Directory of Open Access Journals (Sweden)

    F. Sdao

    2005-01-01

    Full Text Available This paper reports the results of geological and geomorphological surveys and the first results of a still in progress GPS monitoring campaign, taken on a large and ancient landslide located near Avigliano town (Basilicata region, South Italy. The landslide occurs on structurally complex clayey-marly terrains and it is classifiable as a multiple and complex roto-translational-earthflow landslide. In the last years this landslide has been affected by frequent reactivations that have been the cause of grave damages to the urban structures in the area. During January 2004, in order to monitor the present kinematics of the landslide body, a GPS network was installed. Until today several GPS surveys have been carried out. The results of GPS data analysis show centimetres level motions going on the landslide. The final goal of the research will be to define a hazard evaluation and an evolution model of the landslide, using the integrated information coming from GPS and geomorphological surveys.

  10. DEM resolution effects on shallow landslide hazard and soil redistribution modelling

    NARCIS (Netherlands)

    Claessens, L.F.G.; Heuvelink, G.B.M.; Schoorl, J.M.; Veldkamp, A.

    2005-01-01

    In this paper we analyse the effects of digital elevation model (DEM) resolution on the results of a model that simulates spatially explicit relative shallow landslide hazard and soil redistribution patterns and quantities. We analyse distributions of slope, specific catchment area and relative haza

  11. Spatial hazard analysis and prediction on rainfall-induced landslide using GIS

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The application of landslide hazard model cou-pled with GIS provides an effective means to spatial hazardanalysis and prediction on rainfall-induced landslides. Amodified SINMAP model is established based upon the sys-tematic investigation on previous GIS-based landslide analy-sis models. By integrating the landslide deterministic modelwith the hydrological distribution model based on DEM, thismodel deeply studied the effect of underground water dis-tribution due to rainfall on the slope stability and landslideoccurrence, including the effect of dynamic water pressureresulting from the down slope seepage process as well as thatof static water pressure. Its applicability has been testified onthe Xiaojiang watershed, the rainfall-induced landslideswidespread area in Southeast China. Detailed discussion wascarried out on the spatial distribution characteristics oflandslide hazard and its extending trend, as well as thequantitative relationship between landslide hazard with pre-cipitation, slope angle and specific catchment area in theXiaojiang watershed. And the precipitation threshold forlandslide occurrence was estimated. These analytical resultsare proved useful for geohazard control and engineeringdecision-making in the Xiaojiang watershed.

  12. Landslides Zonation Hazard: relation between geological structures and landslides occurrence in hilly tropical regions of Brazil

    Directory of Open Access Journals (Sweden)

    RODRIGO I. CERRI

    2017-08-01

    Full Text Available ABSTRACT This paper presents a new approach of landslides zonation hazard studies, based on an integrated study of structural data along with geomorphological and external factors, in a hilly regions of Brazil, covered by a tropical humid rain-forest, called Serra do Mar. The Serra do Mar consists of a hilly region along the east coast of Brazil, with high slopes and many geological structures in a gneiss - migmatitic terrain. In contrast to traditional approaches, this method proposes that structural data (foliation, fractures and bedding planes and its relation with the slope geometry, is important to be consider in the landslide zonation hazard, along with declivity, relative relief, soil and rock properties, land use and vegetation cover and hydrogeological and climate factors. Results show that slopes with high hazard have the same dip direction of geological structures. Landslide zonation hazard using structural data contributes to a better understanding of how these structures, preserved in tropical residual soils, influence on slope stability and generates landslides.

  13. Landslides Zonation Hazard: relation between geological structures and landslides occurrence in hilly tropical regions of Brazil.

    Science.gov (United States)

    Cerri, Rodrigo I; Reis, Fábio A G V; Gramani, Marcelo F; Giordano, Lucilia C; Zaine, José Eduardo

    2017-08-31

    This paper presents a new approach of landslides zonation hazard studies, based on an integrated study of structural data along with geomorphological and external factors, in a hilly regions of Brazil, covered by a tropical humid rain-forest, called Serra do Mar. The Serra do Mar consists of a hilly region along the east coast of Brazil, with high slopes and many geological structures in a gneiss - migmatitic terrain. In contrast to traditional approaches, this method proposes that structural data (foliation, fractures and bedding planes) and its relation with the slope geometry, is important to be consider in the landslide zonation hazard, along with declivity, relative relief, soil and rock properties, land use and vegetation cover and hydrogeological and climate factors. Results show that slopes with high hazard have the same dip direction of geological structures. Landslide zonation hazard using structural data contributes to a better understanding of how these structures, preserved in tropical residual soils, influence on slope stability and generates landslides.

  14. Climate services for adapting landslide hazard prevention measures in the Vrancea Seismic Region

    Science.gov (United States)

    Micu, Dana; Balteanu, Dan; Jurchescu, Marta; Sima, Mihaela; Micu, Mihai

    2014-05-01

    The Vrancea Seismic Region is covering an area of about 8 000 km2 in the Romanian Curvature Carpathians and Subcarpathians and it is considered one of Europe's most intensely multi-hazard-affected areas. Due to its geomorphic traits (heterogeneous morphostructural units of flysch mountains and molasse hills and depressions), the area is strongly impacted by extreme hydro-meteorological events which are potentially enhancing the numerous damages inflicted to a dense network of human settlements. An a priori knowledge of future climate change is a useful climate service for local authorities to develop regional adapting strategies and adequate prevention/preparedness frameworks. This paper aims at integrating the results of the high-resolution climate projections over the 21st century (within the FP7 ECLISE project) into the regional landslide hazard assessment. The requirements of users (Civil Protection, Land management, local authorities) for this area refer to reliable and high-resolution spatial data on landslide and flood hazard for short and medium-term risk management strategies. An insight into the future behavior of climate variability in the Vrancea Seismic Region, based on future climate projections of three regional models, under three RCPs (2.6, 4.5, 8.6), suggests a clear warming, both annually and seasonally and a rather limited annual precipitation decrease, but with a strong change of seasonality. A landslide inventory of 2485 cases (shallow and medium seated earth, debris and rock slides and earth and debris flows) was obtained based on large scale geomorphological mapping and aerial photos support (GeoEye, DigitalGlobe; provided by GoogleEarth and BingMaps). The landslides are uniformly distributed across the area, being considered representative for the entire morphostructural environment. Landslide susceptibility map was obtained using multivariate statistical analysis (logistic regression), while a relative landslide hazard index was computed

  15. Advances in Landslide Hazard Forecasting: Evaluation of Global and Regional Modeling Approach

    Science.gov (United States)

    Kirschbaum, Dalia B.; Adler, Robert; Hone, Yang; Kumar, Sujay; Peters-Lidard, Christa; Lerner-Lam, Arthur

    2010-01-01

    A prototype global satellite-based landslide hazard algorithm has been developed to identify areas that exhibit a high potential for landslide activity by combining a calculation of landslide susceptibility with satellite-derived rainfall estimates. A recent evaluation of this algorithm framework found that while this tool represents an important first step in larger-scale landslide forecasting efforts, it requires several modifications before it can be fully realized as an operational tool. The evaluation finds that the landslide forecasting may be more feasible at a regional scale. This study draws upon a prior work's recommendations to develop a new approach for considering landslide susceptibility and forecasting at the regional scale. This case study uses a database of landslides triggered by Hurricane Mitch in 1998 over four countries in Central America: Guatemala, Honduras, EI Salvador and Nicaragua. A regional susceptibility map is calculated from satellite and surface datasets using a statistical methodology. The susceptibility map is tested with a regional rainfall intensity-duration triggering relationship and results are compared to global algorithm framework for the Hurricane Mitch event. The statistical results suggest that this regional investigation provides one plausible way to approach some of the data and resolution issues identified in the global assessment, providing more realistic landslide forecasts for this case study. Evaluation of landslide hazards for this extreme event helps to identify several potential improvements of the algorithm framework, but also highlights several remaining challenges for the algorithm assessment, transferability and performance accuracy. Evaluation challenges include representation errors from comparing susceptibility maps of different spatial resolutions, biases in event-based landslide inventory data, and limited nonlandslide event data for more comprehensive evaluation. Additional factors that may improve

  16. Advances in Landslide Hazard Forecasting: Evaluation of Global and Regional Modeling Approach

    Science.gov (United States)

    Kirschbaum, Dalia B.; Adler, Robert; Hone, Yang; Kumar, Sujay; Peters-Lidard, Christa; Lerner-Lam, Arthur

    2010-01-01

    A prototype global satellite-based landslide hazard algorithm has been developed to identify areas that exhibit a high potential for landslide activity by combining a calculation of landslide susceptibility with satellite-derived rainfall estimates. A recent evaluation of this algorithm framework found that while this tool represents an important first step in larger-scale landslide forecasting efforts, it requires several modifications before it can be fully realized as an operational tool. The evaluation finds that the landslide forecasting may be more feasible at a regional scale. This study draws upon a prior work's recommendations to develop a new approach for considering landslide susceptibility and forecasting at the regional scale. This case study uses a database of landslides triggered by Hurricane Mitch in 1998 over four countries in Central America: Guatemala, Honduras, EI Salvador and Nicaragua. A regional susceptibility map is calculated from satellite and surface datasets using a statistical methodology. The susceptibility map is tested with a regional rainfall intensity-duration triggering relationship and results are compared to global algorithm framework for the Hurricane Mitch event. The statistical results suggest that this regional investigation provides one plausible way to approach some of the data and resolution issues identified in the global assessment, providing more realistic landslide forecasts for this case study. Evaluation of landslide hazards for this extreme event helps to identify several potential improvements of the algorithm framework, but also highlights several remaining challenges for the algorithm assessment, transferability and performance accuracy. Evaluation challenges include representation errors from comparing susceptibility maps of different spatial resolutions, biases in event-based landslide inventory data, and limited nonlandslide event data for more comprehensive evaluation. Additional factors that may improve

  17. Application of the improved fuzzy analytic hierarchy process for landslide hazard assessment based on RS and GIS

    Science.gov (United States)

    Li, Baishou; Gao, Yujiu

    2015-12-01

    The landslide is a geological disaster that caused the second disruptions and losses next to the earthquake, and people around the world suffered a serious threat to their lives and property damage as a result of landslide disaster every year. So carrying on the study of the landslide hazard will create important theoretical meaning and practical value for proposing targeted prevention and treatment measures. Landslides occur more frequently in Guangxi where serious landslide disasters run riot because of its unique karst topography environment and abundant rainfall. The Wanxiu District of Wuzhou, Guangxi was selected as the study area, the landslide hazard zonation evaluation was studied on the basis of RS and GIS technology. The factors that influence landslide occurrence, such as elevation, slope inclination, slope aspect, curvature and distance to streams were derived from the DEM; land use was extracted from the Google Earth image; lithology was digitalized from the geologic map; rainfall information was from the literature. An improved analytic hierarchy process was presented to determine the index weight in this study. The method weakens the uncertainty in the process of comparing the importance of each factor, it need not to do the consistency check, which can also reduce the iteration times enormously, and improve operating speed. Combined with fuzzy comprehensive evaluation method, the landslide hazard mapping of the study area was made according to the maximum membership degree principle. The resulting map can be used to provide some reference values for risk management, land-use planning and urbanization.

  18. A NOVEL SOFT COMPUTING MODEL ON LANDSLIDE HAZARD ZONE MAPPING

    Directory of Open Access Journals (Sweden)

    Iqbal Quraishi

    2012-11-01

    Full Text Available The effect of landslide is very prominent in India as well as world over. In India North-East region and all the areas beneath the Himalayan range is prone to landslide. As state wise Uttrakhand, Himachal Pradesh and northern part of West Bengal are identified as a risk zone for landslide. In West Bengal, Darjeeling area is identified as our focus zone. There are several types of landslides depending upon various conditions. Most contributing factor of landslide is Earthquakes. Both field and the GIS data are very versatile and large in amount. Creating a proper data warehouse includes both Remote and field studies. Our proposed soft computing model merge the field and remote sensing data and create an optimized landslide susceptible map of the zone and also provide a broad risk assessment. It takes into account census and economic survey data as an input to calculate and predict the probable number of damaged houses, roads, other amenities including the effect on GDP. The model is highly customizable and tends to provide situation specific results. A fuzzy logic based approach has been considered to partially implement the model in terms of different parameter data sets to show the effectiveness of the proposed model.

  19. An establishment on the hazard mitigation system of large scale landslides for Zengwen reservoir watershed management in Taiwan

    Science.gov (United States)

    Tsai, Kuang-Jung; Lee, Ming-Hsi; Chen, Yie-Ruey; Huang, Meng-Hsuan; Yu, Chia-Ching

    2016-04-01

    Extremely heavy rainfall with accumulated rainfall amount more than 2900mm within continuous 3 day event occurred at southern Taiwan has been recognized as a serious natural hazard caused by Morakot typhoon in august, 2009. Very destructive large scale landslides and debris flows were induced by this heavy rainfall event. According to the satellite image processing and monitoring project was conducted by Soil & Water Conservation Bureau after Morakot typhoon. More than 10904 sites of landslide with total sliding area of 18113 ha were significantly found by this project. Also, the field investigation on all landslide areas were executed by this research on the basis of disaster type, scale and location related to the topographic condition, colluvium soil characteristics, bedrock formation and geological structure after Morakot hazard. The mechanism, characteristics and behavior of this large scale landslide combined with debris flow disasters are analyzed and Investigated to rule out the interaction of factors concerned above and identify the disaster extent of rainfall induced landslide during the period of this study. In order to reduce the disaster risk of large scale landslide and debris flow, the adaption strategy of hazard mitigation system should be set up as soon as possible and taken into consideration of slope land conservation, landslide control countermeasure planning, disaster database establishment, environment impact analysis and disaster risk assessment respectively. As a result, this 3-year research has been focused on the field investigation by using GPS/GIS/RS integration, mechanism and behavior study regarding to the rainfall induced landslide occurrence, disaster database and hazard mitigation system establishment. In fact, this project has become an important issue which was seriously concerned by the government and people live in Taiwan. Hopefully, all results come from this research can be used as a guidance for the disaster prevention and

  20. Landslide susceptibility mapping using a bivariate statistical model in a tropical hilly area of southeastern Brazil

    Science.gov (United States)

    Araújo, J. P. C.; DA Silva, L. M.; Dourado, F. A. D.; Fernandes, N.

    2015-12-01

    Landslides are the most damaging natural hazard in the mountainous region of Rio de Janeiro State in Brazil, responsible for thousands of deaths and important financial and environmental losses. However, this region has currently few landslide susceptibility maps implemented on an adequate scale. Identification of landslide susceptibility areas is fundamental in successful land use planning and management practices to reduce risk. This paper applied the Bayes' theorem based on weight of evidence (WoE) using 8 landslide-related factors in a geographic information system (GIS) for landslide susceptibility mapping. 378 landslide locations were identified and mapped on a selected basin in the city of Nova Friburgo, triggered by the January 2011 rainfall event. The landslide scars were divided into two subsets: training and validation subsets. The 8 landslide-related factors weighted by WoE were performed using chi-square test to indicate which variables are conditionally independent of each other to be used in the final map. Finally, the maps of weighted factors were summed up to construct the landslide susceptibility map and validated by the validation landslide subset. According to the results, slope, aspect and contribution area showed the higher positive spatial correlation with landslides. In the landslide susceptibility map, 21% of the area presented very low and low susceptibilities with 3% of the validation scars, 41% presented medium susceptibility with 22% of the validation scars and 38% presented high and very high susceptibilities with 75% of the validation scars. The very high susceptibility class stands for 16% of the basin area and has 54% of the all scars. The approach used in this study can be considered very useful since 75% of the area affected by landslides was included in the high and very high susceptibility classes.

  1. Methodologies for the assessment of earthquake-triggered landslides hazard. A comparison of Logistic Regression and Artificial Neural Network models.

    Science.gov (United States)

    García-Rodríguez, M. J.; Malpica, J. A.; Benito, B.

    2009-04-01

    In recent years, interest in landslide hazard assessment studies has increased substantially. They are appropriate for evaluation and mitigation plan development in landslide-prone areas. There are several techniques available for landslide hazard research at a regional scale. Generally, they can be classified in two groups: qualitative and quantitative methods. Most of qualitative methods tend to be subjective, since they depend on expert opinions and represent hazard levels in descriptive terms. On the other hand, quantitative methods are objective and they are commonly used due to the correlation between the instability factors and the location of the landslides. Within this group, statistical approaches and new heuristic techniques based on artificial intelligence (artificial neural network (ANN), fuzzy logic, etc.) provide rigorous analysis to assess landslide hazard over large regions. However, they depend on qualitative and quantitative data, scale, types of movements and characteristic factors used. We analysed and compared an approach for assessing earthquake-triggered landslides hazard using logistic regression (LR) and artificial neural networks (ANN) with a back-propagation learning algorithm. One application has been developed in El Salvador, a country of Central America where the earthquake-triggered landslides are usual phenomena. In a first phase, we analysed the susceptibility and hazard associated to the seismic scenario of the 2001 January 13th earthquake. We calibrated the models using data from the landslide inventory for this scenario. These analyses require input variables representing physical parameters to contribute to the initiation of slope instability, for example, slope gradient, elevation, aspect, mean annual precipitation, lithology, land use, and terrain roughness, while the occurrence or non-occurrence of landslides is considered as dependent variable. The results of the landslide susceptibility analysis are checked using landslide

  2. Communicating landslide risk by combining hazard and open infrastructure data in interactive visualizations

    Science.gov (United States)

    Tost, Jordi; Olen, Stephanie M.; Bookhagen, Bodo; Heidmann, Frank

    2017-04-01

    The DIGENTI project ("DIGitaler ENtscheiderTIsch für das Naturgefahrenmanagement auf Basis von Satellitendaten und Volunteered Geographic Information") has the goal of quantifying and communicating the threat of natural hazards in the Cesar and La Guajira departments of northeast Colombia. The end-goal of the project is to provide an interactive guide for policy and decision makers, and for disaster relief coordination. Over the last years, abundant research has been done in order to analyze risk and to provide relevant information that improves effectiveness in disaster management. The communication of natural hazards risk has traditionally been built upon the estimation of hazard maps. In the context of landslides, hazard maps are used to depict potential danger from landslides and visualize the possibility of future landsliding throughout a given area. Such hazard maps provide a static snapshot of the local estimated threat in a region. However, in mountainous regions, a sufficiently large landslide in remote mountainous areas may represent a potential threat to settlements located downstream of a landslide event. The research presented here proposes an approach to visualize and interactively explore landslide risk by combining static hazard maps, hydrologic networks, and OpenStreetMap data. We estimated the potential for hillslope instabilities scenarios in the region of interest by using the TanDEM-X World DEM to calculate a suite Factor of Safety (FOS) maps. The FOS estimates the ratio of total resisting and driving forces to hillslope mass movements. By combining the World DEM with other environmental data (e.g., the Harmonized World Soil Database), we were able to create a suite of high-resolution landslide potential maps for the region of interest. The suite of FOS maps are calculated based on user-selectable parameters (e.g, total mass sliding thickness) that are not well constrained by field observations. We additionally use the TanDEM-X World DEM to

  3. Assessing landslide susceptibility, hazards and sediment yield in the Río El Estado watershed, Pico de Orizaba volcano, Mexico

    Science.gov (United States)

    Legorreta Paulin, G.; Bursik, M. I.; Lugo Hubp, J.; Aceves Quesada, J. F.

    2014-12-01

    This work provides an overview of the on-going research project (Grant SEP-CONACYT # 167495) from the Institute of Geography at the National Autonomous University of Mexico (UNAM) that seeks to conduct a multi-temporal landslide inventory, analyze the distribution of landslides, and characterize landforms that are prone to slope instability by using Geographic Information Systems (GIS). The study area is the Río El Estado watershed that covers 5.2 km2 and lies on the southwestern flank of Pico de Orizaba volcano.The watershed was studied by using aerial photographs, fieldwork, and adaptation of the Landslide Hazard Zonation Protocol of the Washington State Department of Natural Resources, USA. 107 gravitational slope failures of six types were recognized: shallow landslides, debris-avalanches, deep-seated landslides, debris flows, earthflows, and rock falls. This analysis divided the watershed into 12 mass-wasting landforms on which gravitational processes occur: inner gorges, headwalls, active scarps of deep-seated landslides, meanders, plains, rockfalls, non-rule-identified inner gorges, non-rule-identified headwalls, non-rule-identified converging hillslopes and three types of hillslopes classified by their gradient: low, moderate, and high. For each landform the landslide area rate and the landslide frequency rate were calculated as well as the overall hazard rating. The slope-stability hazard rating has a range that goes from low to very high. The overall hazard rating for this watershed was very high. The shallow slide type landslide was selected and area and volume of individual landslides were retrieved from the watershed landslide inventory geo-database, to establish an empirical relationship between area and volume that takes the form of a power law. The relationship was used to estimate the total volume of landslides in the study area. The findings are important to understand the long-term evolution of the southwestern flank stream system of Pico de

  4. Comparison of Structurally Controlled Landslide Hazard Simulation to the Co-seismic Landslides Caused by the M 7.2 2013 Bohol Earthquake.

    Science.gov (United States)

    Galang, J. A. M. B.; Eco, R. C.; Lagmay, A. M. A.

    2014-12-01

    The M_w 7.2 October 15, 2013 Bohol earthquake is one of the more destructive earthquake to hit the Philippines in the 21st century. The epicenter was located in Sagbayan municipality, central Bohol and was generated by a previously unmapped reverse fault called the "Inabanga Fault". The earthquake resulted in 209 fatalities and over 57 million USD worth of damages. The earthquake generated co-seismic landslides most of which were related to fault structures. Unlike rainfall induced landslides, the trigger for co-seismic landslides happen without warning. Preparations for this type of landslides rely heavily on the identification of fracture-related slope instability. To mitigate the impacts of co-seismic landslide hazards, morpho-structural orientations of discontinuity sets were mapped using remote sensing techniques with the aid of a Digital Terrain Model (DTM) obtained in 2012. The DTM used is an IFSAR derived image with a 5-meter pixel resolution and approximately 0.5 meter vertical accuracy. Coltop 3D software was then used to identify similar structures including measurement of their dip and dip directions. The chosen discontinuity sets were then keyed into Matterocking software to identify potential rock slide zones due to planar or wedged discontinuities. After identifying the structurally-controlled unstable slopes, the rock mass propagation extent of the possible rock slides was simulated using Conefall. Separately, a manually derived landslide inventory has been performed using post-earthquake satellite images and LIDAR. The results were compared to the landslide inventory which identified at least 873 landslides. Out of the 873 landslides identified through the inventory, 786 or 90% intersect the simulated structural-controlled landslide hazard areas of Bohol. The results show the potential of this method to identify co-seismic landslide hazard areas for disaster mitigation. Along with computer methods to simulate shallow landslides, and debris flow

  5. Ground landslide hazard potency using geoelectrical resistivity analysis and VS30, case study at geophysical station, Lembang, Bandung

    Science.gov (United States)

    Rohadi, Supriyanto; Sakya, Andi Eka; Masturyono, Murjaya, Jaya; Sunardi, Bambang; Rasmid, Ngadmanto, Drajat; Susilanto, Pupung; Nugraha, Jimmi; Pakpahan, Suliyanti

    2017-07-01

    We have conducted geoelectric resistivity and shear wave velocity (Vs30) study to identify the landslide potential hazard, around Geophysics Station Lembang, Bandung (107,617° E and 6,825° S). The the geoelectric analysis using Dipole-Dipole resitivity configuration, while shear wave velocity analysis performed using the Multichannel Analysis of Surface Wave (MASW). The study results indicate that the assumed soil or clay depth from the electrical resistivity observation was in accordance with the confirmed soil or clay depth by the MASW investigation. Based on these conditions, indicate the high potential of landsliding in this area, landslide potential supported by high slope angle in this area.

  6. Contribution of physical modelling to climate-driven landslide hazard mapping: an alpine test site

    Science.gov (United States)

    Vandromme, R.; Desramaut, N.; Baills, A.; Hohmann, A.; Grandjean, G.; Sedan, O.; Mallet, J. P.

    2012-04-01

    The aim of this work is to develop a methodology for integrating climate change scenarios into quantitative hazard assessment and especially their precipitation component. The effects of climate change will be different depending on both the location of the site and the type of landslide considered. Indeed, mass movements can be triggered by different factors. This paper describes a methodology to address this issue and shows an application on an alpine test site. Mechanical approaches represent a solution for quantitative landslide susceptibility and hazard modeling. However, as the quantity and the quality of data are generally very heterogeneous at a regional scale, it is necessary to take into account the uncertainty in the analysis. In this perspective, a new hazard modeling method is developed and integrated in a program named ALICE. This program integrates mechanical stability analysis through a GIS software taking into account data uncertainty. This method proposes a quantitative classification of landslide hazard and offers a useful tool to gain time and efficiency in hazard mapping. However, an expertise approach is still necessary to finalize the maps. Indeed it is the only way to take into account some influent factors in slope stability such as heterogeneity of the geological formations or effects of anthropic interventions. To go further, the alpine test site (Barcelonnette area, France) is being used to integrate climate change scenarios into ALICE program, and especially their precipitation component with the help of a hydrological model (GARDENIA) and the regional climate model REMO (Jacob, 2001). From a DEM, land-cover map, geology, geotechnical data and so forth the program classifies hazard zones depending on geotechnics and different hydrological contexts varying in time. This communication, realized within the framework of Safeland project, is supported by the European Commission under the 7th Framework Programme for Research and Technological

  7. Modelling the landslide area and sediment discharge in landslide-dominated region, Taiwan

    Science.gov (United States)

    Teng, Tse-Yang; Huang, -Chuan, Jr.; Lee, Tsung-Yu; Chen, Yi-Chin; Jan, Ming-Young; Liu, Cheng-Chien

    2016-04-01

    Many studies have indicated the magnified increase of rainfall intensification, landsliding and subsequent sediment discharge due to the global warming effect. However, a few works synthesized the "chain reaction" from rainfall, landsliding to sediment discharge at the same time because of the limited observations of landslide area and sediment discharge during episodes. Besides, the sediment transport strongly depends on the sediment supply and stream power which interact conditionally. In this study, our goal is to build a model that can simulate time-series landslide area and subsequent sediment discharge. The synthesized model would be applied onto Tsengwen Reservoir watershed in southern Taiwan, where lots of landslides occur every year. Unlike other studies, our landslide model considers not only rainfall effect but also previous landslide status, which may be applied to landslide-dominated regions and explains the irrelevant relationship between typhoon rainfall and landslide area. Furthermore, our sediment transport model considers the sediment budget which couples transport- and supply-limited of sediment. The result shows that the simulated time-series landslide area and the sediment transport agree with the observation and the R2 are 0.88 and 0.56, respectively. Reactivated ratio of previous landslide area is 72.7% which indicates the high reoccurrence of historical landslide in landslide-dominated regions. We divided nine historical typhoons into three periods to demonstrate the effect of sediment supply/supply-limited condition upon sediment transport. For instance, the rainfall is smaller in period 3 than in period 1 but the sediment transport is higher in period 3 due to the catastrophic landslide (typhoon Morakot) during period 2. We argue that quantifying sediment transport should couple not only with water discharge but sediment budget, which is rarely considered in calculating sediment transport. Moreover, the parameterization of the controlling

  8. Regional analysis assessment of landslide hazard and zoning map for transmission line route selection using GIS

    Science.gov (United States)

    Baharuddin, I. N. Z.; Omar, R. C.; Usman, F.; Mejan, M. A.; Abd Halim, M. K.; Zainol, M. A.; Zulkarnain, M. S.

    2013-06-01

    The stability of ground as foundation for infrastructure development is always associated with geology and geomorphology aspects. Failure to carefully analyze these aspects may induce ground instability such subsidence and landslide which eventually can cause catastrophe to the infrastructure i.e. instability of transmission tower. However, in some cases such as the study area this is unavoidable. A GIS system for analysis of route was favoured to perform optimal route predictions based selection by incorporating multiple influence factors into its analysis by incorporating the Landslide Hazard Map (LHM) that was produced on basis of slope map, aspect map, land use map and geological map with the help of ArcGIS using weighted overlay method. Based on LHM it is safe to conclude that the proposed route for Ulu Jelai- Neggiri-Lebir-LILO transmission line has very low risk in term of landslides.

  9. Developing a methodology for the national-scale assessment of rainfall-induced landslide hazard in a changing climate

    Science.gov (United States)

    Jurchescu, Marta; Micu, Dana; Sima, Mihaela; Bălteanu, Dan; Bojariu, Roxana; Dumitrescu, Alexandru; Dragotă, Carmen; Micu, Mihai; Senzaconi, Francisc

    2017-04-01

    Landslides together with earthquakes and floods represent the main natural hazards in Romania, causing major impacts to human activities. The RO-RISK (Disaster Risk Evaluation at a National Level) project is a flagship project aimed to strengthen risk prevention and management in Romania, by evaluating - among the specific risks in the country - landslide hazard and risk at a national level. Landslide hazard is defined as "the probability of occurrence within a specified period of time and within a given area of a landslide of a given magnitude" (Varnes 1984; Guzzetti et al. 1999). Nevertheless, most landslide ʿhazardʾ maps only consist in susceptibility (i.e. spatial probability) zonations without considering temporal or magnitude information on the hazard. This study proposes a methodology for the assessment of landslide hazard at the national scale on a scenario basis, while also considering changes in hazard patterns and levels under climate change conditions. A national landslide database consisting of more than 3,000 records has been analyzed against a meteorological observation dataset in order to assess the relationship between precipitation and landslides. Various extreme climate indices were computed in order to account for the different rainfall patterns able to prepare/trigger landslides (e.g. extreme levels of seasonal rainfall, 3-days rainfall or number of consecutive rainy days with different return periods). In order to derive national rainfall thresholds, i.e. valid for diverse climatic environments across the country, values in the parameter maps were rendered comparable by means of normalization with the mean annual precipitation and the rainy-day-normal. A hazard assessment builds on a frequency-magnitude relationship. In the current hazard scenario approach, frequency was kept constant for each single map, while the magnitude of the expected geomorphic event was modeled in relation to the distributed magnitude of the triggering factor. Given

  10. Landslide Inventory and Susceptibility Mapping in Tropical Areas - Southern Mexico

    Science.gov (United States)

    Gaidzik, K.; Ramirez-Herrera, M. T.; Regmi, N. R.; Leshchinsky, B. A.

    2016-12-01

    Landslides are one of the common catastrophic phenomena in the world. In regions of humid-warm tropical climate they are triggered by extreme storms causing loss of life and economic devastation. In this study we mapped susceptibility to landslides in the tropical mountains of Guerrero (South Mexico) based on the inventory of landslide features triggered by the hurricane Manuel of September 2013. Landslide inventory was produced using interpretation of satellite images and automatic identification of landslides employing the Contour Connection Method (CCM). A map of susceptibility to landslides was developed by computing probability of landslide occurrence from statistical relationships of existing landslides using LiDAR elevation model and derived landslide-causing factors using a logistic regression method. Landslide inventory includes 419 features produced by the hurricane Manuel on the area of 22 km2, and > 1,000 older features, suggesting high landslide activity in this area. Most landslides in the region are small, but some large slides exist, such as the catastrophic landslide in La Pintada that caused 71 fatalities and destroyed a large part of the village. Our results indicate that the distance to streams, human activity, presence or absence of dense vegetation and orientation of slopes (on some areas) strongly influence the spatial distribution of landslides. Results showed high susceptibility zones encompass 30% of the study area and occur mostly along topographic convergence. Applied approach identified most of the landslides within the high susceptibility zone and suggested that it is a valid applicable method to map areas susceptible to landslides in southern Mexico but also on other humid-warm tropical regions.

  11. Assessment of earthquake-induced landslides hazard in El Salvador after the 2001 earthquakes using macroseismic analysis

    Science.gov (United States)

    Esposito, Eliana; Violante, Crescenzo; Giunta, Giuseppe; Ángel Hernández, Miguel

    2016-04-01

    Two strong earthquakes and a number of smaller aftershocks struck El Salvador in the year 2001. The January 13 2001 earthquake, Mw 7.7, occurred along the Cocos plate, 40 km off El Salvador southern coast. It resulted in about 1300 deaths and widespread damage, mainly due to massive landsliding. Two of the largest earthquake-induced landslides, Las Barioleras and Las Colinas (about 2x105 m3) produced major damage to buildings and infrastructures and 500 fatalities. A neighborhood in Santa Tecla, west of San Salvador, was destroyed. The February 13 2001 earthquake, Mw 6.5, occurred 40 km east-southeast of San Salvador. This earthquake caused over 300 fatalities and triggered several landslides over an area of 2,500 km2 mostly in poorly consolidated volcaniclastic deposits. The La Leona landslide (5-7x105 m3) caused 12 fatalities and extensive damage to the Panamerican Highway. Two very large landslides of 1.5 km3 and 12 km3 produced hazardous barrier lakes at Rio El Desague and Rio Jiboa, respectively. More than 16.000 landslides occurred throughout the country after both quakes; most of them occurred in pyroclastic deposits, with a volume less than 1x103m3. The present work aims to define the relationship between the above described earthquake intensity, size and areal distribution of induced landslides, as well as to refine the earthquake intensity in sparsely populated zones by using landslide effects. Landslides triggered by the 2001 seismic sequences provided useful indication for a realistic seismic hazard assessment, providing a basis for understanding, evaluating, and mapping the hazard and risk associated with earthquake-induced landslides.

  12. A complex geo-scientific strategy for landslide hazard mitigation ─ from airborne mapping to ground monitoring

    Directory of Open Access Journals (Sweden)

    W. Jaritz

    2008-01-01

    Full Text Available After a large landslide event in Sibratsgfäll/Austria several exploration methods were evaluated on their applicability to investigate and monitor landslide areas. The resulting optimised strategy consists of the combined application of airborne electromagnetics, ground geoelectrical measurements and geoelectrical monitoring combined with hydrological and geological mapping and geotechnical modelling. Interdisciplinary communication and discussion was the primary key to assess this complicated hazard situation.

  13. Geospatial Data Integration for Assessing Landslide Hazard on Engineered Slopes

    Science.gov (United States)

    Miller, P. E.; Mills, J. P.; Barr, S. L.; Birkinshaw, S. J.

    2012-07-01

    Road and rail networks are essential components of national infrastructures, underpinning the economy, and facilitating the mobility of goods and the human workforce. Earthwork slopes such as cuttings and embankments are primary components, and their reliability is of fundamental importance. However, instability and failure can occur, through processes such as landslides. Monitoring the condition of earthworks is a costly and continuous process for network operators, and currently, geospatial data is largely underutilised. The research presented here addresses this by combining airborne laser scanning and multispectral aerial imagery to develop a methodology for assessing landslide hazard. This is based on the extraction of key slope stability variables from the remotely sensed data. The methodology is implemented through numerical modelling, which is parameterised with the slope stability information, simulated climate conditions, and geotechnical properties. This allows determination of slope stability (expressed through the factor of safety) for a range of simulated scenarios. Regression analysis is then performed in order to develop a functional model relating slope stability to the input variables. The remotely sensed raster datasets are robustly re-sampled to two-dimensional cross-sections to facilitate meaningful interpretation of slope behaviour and mapping of landslide hazard. Results are stored in a geodatabase for spatial analysis within a GIS environment. For a test site located in England, UK, results have shown the utility of the approach in deriving practical hazard assessment information. Outcomes were compared to the network operator's hazard grading data, and show general agreement. The utility of the slope information was also assessed with respect to auto-population of slope geometry, and found to deliver significant improvements over the network operator's existing field-based approaches.

  14. The role of topography in the scaling distribution of landslide areas: A cellular automata modeling approach

    Science.gov (United States)

    Liucci, Luisa; Melelli, Laura; Suteanu, Cristian; Ponziani, Francesco

    2017-08-01

    Power law scaling has been widely observed in the frequency distribution of landslide sizes. The exponent of the power-law characterizes the probability of landslide magnitudes and it thus represents an important parameter for hazard assessment. The reason for the universal scaling behavior of landslides is still debated and the role of topography has been explored in terms of possible explanation for this type of behavior. We built a simple cellular automata model to investigate this issue, as well as the relationships between the scaling properties of landslide areas and the changes suffered by the topographic surface affected by landslides. The dynamics of the model is controlled by a temporal rate of weakening, which drives the system to instability, and by topography, which defines both the quantity of the displaced mass and the direction of the movement. Results show that the model is capable of reproducing the scaling behavior of real landslide areas and suggest that topography is a good candidate to explain their scale-invariance. In the model, the values of the scaling exponents depend on how fast the system is driven to instability; they are less sensitive to the duration of the driving rate, thus suggesting that the probability of landslide areas could depend on the intensity of the triggering mechanism rather than on its duration, and on the topographic setting of the area. Topography preserves the information concerning the statistical distribution of areas of landslides caused by a driving mechanism of given intensity and duration.

  15. Landslide disaster in the loess area of China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and becomes major factors hindering the social and economic development of loess regions. Through different indexes, the authors divided the landslides into 9 principal types and analyzed the distribution characteristics of loess landslide in time and space, the affecting factors and mechanism of landslides. It is pointed out that time and spatial distributions of landslides are closely correlative to topographic and geomorphic conditions, earthquake and rainfall, and the key influencing factors include topography, geomorphology, new tectonic movements, earthquake activity, surface water, ground water and human activities. The authors emphasized that the natural condition of loess areas was favorable to landslides, human activities impelled its occurrence and that controlling the loess landslide was an urgent task for sustainable development in the loess zone.

  16. Study on landslide hazard zonation based on factor weighting-rating theory in Slanic Prahova

    Science.gov (United States)

    Maftei, R.-M.; Vina, G.; Filipciuc, C.

    2012-04-01

    Studying the risks caused by landslides is important in the context of its forecast triggering. This study mainly integrates the background data that are related to historical and environmental factors and also current triggering factors. The theory on zoning hazard caused by landslides, Landslide Hazard Zonation, (LHZ) appeared in the 1960s. In this period the U.S. and many European countries began to use other triggers factors, besides the slope factor, in achieving hazard zoning. This theory has progressed due to the development of remote sensing and GIS technology, which were used to develop and analys methods and techniques consisting in combining data from different sources. The study of an area involves analysing the geographical position data, estimating the surface, the type of terrain, altitude, identifing the landslides in the area and some geological summary data. Data sources. The data used in this study are: · Landsat 7 satellite images; · 30 m spatial resolution, from which is derived the vegetation index; · topographic maps 1:25 000 from which we can obtain the numerical altitude model (DEM) (used to calculate the slope and relative altitude to land) · geological maps 1:50 000. Studied factors. The main factors used and studied in achieving land slides hazard zoning are: - the rate of displacement, the angle of slope, lithology - the index of vegetation or ground coverage of vegetation (NDVI) - river network, structural factor 1. The calculation of normalized vegetation index is made based on Landsat ETM satellite images. This vegetation factor can be both a principal and a secondary trigger factor in landslides. In areas devoid of vegetation, landslides are triggered more often compared with those in which coverage is greater. 2. Factors derived from the numerical model are the slope and elevation relative altitude. This operation was made using the topographic map 1:25 000 from were the level curvs contour was extracted by digitization, and

  17. Development of Smart Grid for Community and Cyber based Landslide Hazard Monitoring and Early Warning System

    Science.gov (United States)

    Karnawati, D.; Wilopo, W.; Fathani, T. F.; Fukuoka, H.; Andayani, B.

    2012-12-01

    A Smart Grid is a cyber-based tool to facilitate a network of sensors for monitoring and communicating the landslide hazard and providing the early warning. The sensor is designed as an electronic sensor installed in the existing monitoring and early warning instruments, and also as the human sensors which comprise selected committed-people at the local community, such as the local surveyor, local observer, member of the local task force for disaster risk reduction, and any person at the local community who has been registered to dedicate their commitments for sending reports related to the landslide symptoms observed at their living environment. This tool is designed to be capable to receive up to thousands of reports/information at the same time through the electronic sensors, text message (mobile phone), the on-line participatory web as well as various social media such as Twitter and Face book. The information that should be recorded/ reported by the sensors is related to the parameters of landslide symptoms, for example the progress of cracks occurrence, ground subsidence or ground deformation. Within 10 minutes, this tool will be able to automatically elaborate and analyse the reported symptoms to predict the landslide hazard and risk levels. The predicted level of hazard/ risk can be sent back to the network of electronic and human sensors as the early warning information. The key parameters indicating the symptoms of landslide hazard were recorded/ monitored by the electrical and the human sensors. Those parameters were identified based on the investigation on geological and geotechnical conditions, supported with the laboratory analysis. The cause and triggering mechanism of landslide in the study area was also analysed in order to define the critical condition to launch the early warning. However, not only the technical but also social system were developed to raise community awareness and commitments to serve the mission as the human sensors, which will

  18. The Grand Banks Landslide area revisited

    Science.gov (United States)

    Krastel, S.; Feldens, P.; Georgiopoulou, A.; Lindhorst, K.; Llopart, J.; Mehringer, L.; Mosher, D. C.; Piper, D.; Roskoden, R.; Schoenke, M.; Schulten, I.; Stevenson, C.

    2016-12-01

    On November 18, 1929, a M7.2 earthquake occurred beneath the Laurentian Channel off the coast of Newfoundland. Nearly simultaneously, 12 undersea trans-Atlantic communication cables were severed and within two hours, a devastating tsunami struck the south coast of Newfoundland, claiming 28 lives. Only in 1952, it was understood that a slump-generated turbidity current caused the sequential severance of the cables and likely generated the tsunami. The landslide site was visited numerous times as underwater survey technologies evolved. No major head scarp related to the event is recognized. The landslide appears to have affected shallow sediments (top 5-50 m) and was laterally extensive. In order to test the hypothesis that a distributed, laterally extensive, shallow submarine mass failure event caused the tsunami, we collected 1500 km of seismic lines in combination with a dense net of hydroacoustic data during RV Maria S. Merian cruise in autumn 2015. Coring and CPT transects were carried out based on the acoustic data. The data in the failure area show abundant small scarps and several young landslide deposits. Listric faults in the failure area may play an important role for tsunami generation but need to be investigated further. The turbidity currents related to the failure entered the Grand Banks channel system. A complex pattern of bypassing and deposition is found in this complex channel area downslope of the failure area. Very coarse gravel was sampled up to 150 m above the canyon thalweg. First estimates suggest high concentrations of sediments in the flow, which was able to run out over 1000s of kilometers. We have not identified indications for similar large events in the late Holocene.

  19. Suppressing geo-facts in landslide-affected areas

    Science.gov (United States)

    Sajinkumar, Ks; Pradeepkumar, Ap; Rani, Vr; Di Capua, Giuseppe

    2014-05-01

    The Western Ghats, the bold westerly escarpment of India and which borders the eastern portion of Kerala State (India), bears the testimony of frequent landslides, especially during the monsoon season, and they cause widespread damage to life and property. The natural hazards can turn into disasters in this hilly state, due to the high density of population (~800 per km2). The elements at landslide risk in any area include human population, livestock, land and its resources, environmental values, buildings and economic activities. The loss of lives is the most heart breaking side of the story and cannot be compensated in pecuniary terms. The role of the geoscientist comes into picture to protect the life and property from imminent landslides. But the unbiased role of a geoscientist is blocked by several societal issues like fear of disapproval by the public, political interference, false information propagated through the fourth estate and last but not the least the lack of confidence in her/himself as the profession is now mainly non-societal. This paper aims at looking into these issues in a landslide-prone area of the state. The deontological vs consequential ethical behaviours that characterise the responses by the official machinery and the common man conspire to create disastrous situations, which ultimately brings suffering to the common man, while straining the resources of the state through recurrent payment of damages, every year. The "moral vs monetary" values of society and its government is laid bare in Kerala, especially during landslide disasters and the state's social contract obligations sometimes become ambiguous. Another aspect that has to be addressed is the impact on the marginalized during landslide disasters in Kerala. Does the newly instituted 'Disaster Insurance' scheme adequately cover them? What is the ethical dimensions that such schemes address? The Kerala state is the most socially, educationally, and demographically advanced one in

  20. Modeling and Testing Landslide Hazard Using Decision Tree

    Directory of Open Access Journals (Sweden)

    Mutasem Sh. Alkhasawneh

    2014-01-01

    Full Text Available This paper proposes a decision tree model for specifying the importance of 21 factors causing the landslides in a wide area of Penang Island, Malaysia. These factors are vegetation cover, distance from the fault line, slope angle, cross curvature, slope aspect, distance from road, geology, diagonal length, longitude curvature, rugosity, plan curvature, elevation, rain perception, soil texture, surface area, distance from drainage, roughness, land cover, general curvature, tangent curvature, and profile curvature. Decision tree models are used for prediction, classification, and factors importance and are usually represented by an easy to interpret tree like structure. Four models were created using Chi-square Automatic Interaction Detector (CHAID, Exhaustive CHAID, Classification and Regression Tree (CRT, and Quick-Unbiased-Efficient Statistical Tree (QUEST. Twenty-one factors were extracted using digital elevation models (DEMs and then used as input variables for the models. A data set of 137570 samples was selected for each variable in the analysis, where 68786 samples represent landslides and 68786 samples represent no landslides. 10-fold cross-validation was employed for testing the models. The highest accuracy was achieved using Exhaustive CHAID (82.0% compared to CHAID (81.9%, CRT (75.6%, and QUEST (74.0% model. Across the four models, five factors were identified as most important factors which are slope angle, distance from drainage, surface area, slope aspect, and cross curvature.

  1. Evolution trends in vulnerability of R/C buildings exposed to earthquake induced landslide hazard

    Science.gov (United States)

    Fotopoulou, S.; Pitilakis, K.

    2012-04-01

    The assessment of landslide risk depends on the evaluation of landslide hazard and the vulnerability of exposed structures which both change with time. The real, dynamic vulnerability modeling of structures due to landslides may be significantly affected by aging considerations, anthropogenic actions, cumulative damage from past landslide events and retrofitting measures. The present work aims at the development of an efficient analytical methodology to assess the evolution of building vulnerability with time exposed to earthquake -induced landslide hazard. In particular, the aging of typical RC buildings is considered by including probabilistic models of corrosion deterioration of the RC elements within the vulnerability modeling framework. Two potential adverse corrosion scenarios are examined: chloride and carbonation induced corrosion of the steel reinforcement. An application of the proposed methodology to reference low-rise RC buildings exposed to the combined effect of seismically induced landslide differential displacements and reinforcement corrosion is provided. Both buildings with stiff and flexible foundation system standing near the crest of a potentially precarious soil slope are examined. Non linear static time history analyses of the buildings are performed using a fibre-based finite element code. In this analysis type, the applied loads (displacements) at the foundation level vary in the pseudo-time domain, according to a load pattern prescribed as the differential permanent landslide displacement (versus time) curves triggered by the earthquake. The distribution for the corrosion initiation time is assessed through Monte Carlo simulation using appropriate probabilistic models for the carbonation and the chloride induced corrosion. Then, the loss of area of steel over time due to corrosion of the RC elements is modeled as a reduction in longitudinal reinforcing bar cross-sectional area in the fibre section model. Time dependent structural limit

  2. Landslide Hazard Zonation and Risk Assessment of Ramganga Basin in Garhwal Himalaya

    Science.gov (United States)

    Wasini Pandey, Bindhy; Roy, Nikhil

    2016-04-01

    The Himalaya being unique in its physiographic, tectonic and climatic characteristics coupled with many natural and man-made factors is inherently prone to landslides. These landslides lead to mass loss of property and lives every year in Himalayas. Hence, Landslide Hazard Zonation is important to take quick and safe mitigation measures and make strategic planning for future development. The present study tries to explore the causes of landslides in Ramganga Basin in Garhwal Himalaya, which has an established history and inherent susceptibility to massive landslides has been chosen for landslide hazard zonation and risk assessment. The satellite imageries of LANDSAT, IRS P6, ASTER along with Survey of India (SOI) topographical sheets formed the basis for deriving baseline information on various parameters like slope, aspect, relative relief, drainage density, geology/lithology and land use/land cover. The weighted parametric method will be used to determine the degree of susceptibility to landslides. Finally, a risk map will be prepared from the landslide probability values, which will be classified into no risk, very low to moderate, high, and very high to severe landslide hazard risk zones. Keywords: Landslides, Hazard Zonation, Risk Assessment

  3. Geophysics of Volcanic Landslide Hazards: The Inside Story

    Science.gov (United States)

    Finn, C.; Deszcz-Pan, M.; Bedrosian, P. A.

    2013-05-01

    Flank collapses of volcanoes pose significant potential hazards, including triggering lahars, eruptions, and tsunamis. Significant controls on the stability of volcanoes are the distribution of hydrothermal alteration and the location of groundwater. Groundwater position, abundance, and flow rates within a volcano affect the transmission of fluid pressure and the transport of mass and heat. Interaction of groundwater with acid magmatic gases can lead to hydrothermal alteration that mechanically weakens rocks and makes them prone to failure and flank collapse. Therefore, detecting the presence and volume of hydrothermally altered rocks and shallow ground water is critical for evaluating landslide hazards. High-resolution helicopter magnetic and electromagnetic (HEM) data collected over the rugged, ice-covered Mount Adams, Mount Baker, Mount Rainier, Mount St. Helens (Washington) and Mount Iliamna (Alaska) volcanoes, reveal the distribution of alteration, water and ice thickness essential to evaluating volcanic landslide hazards. These data, combined with geological mapping, other geophysical data and rock property measurements, indicate the presence of appreciable thicknesses (>500 m) of water-saturated hydrothermally altered rock west of the modern summit of Mount Rainier in the Sunset Amphitheater region and in the central core of Mount Adams north of the summit. Water-saturated alteration at Mount Baker is restricted to thinner (glaciers on Mount Iliamna. Removal of ice and snow during eruptions and landslide can result in lahars and floods. Ice thickness measurements critical for flood and mudflow hazards studies are very sparse on most volcanoes. The HEM data are used to estimate ice thickness over portions of Mount Baker and Mount Adams volcanoes. The best estimates for ice thickness are obtained over relatively low resistivity (<600 ohm-m) ground for the main ice cap on Mount Adams and over most of the summit of Mount Baker. The modeled distribution of

  4. Landslide hazard assessment of the Black sea coastline (Caucasus, Russia) via drones

    Science.gov (United States)

    Kazeev, Andrey; Postoev, German; Fedotova, Ksenia

    2017-04-01

    Landslide hazard assessment of slopes of Sochi was performed along the railway between the cities Tuapse and Adler (total length 103 km). The railway passes through the territory with active development of hazardous geological processes such as landslides, rock falls and debris-flows. By the beginning of 2016, 36 landslide sites were discovered along the railway (total length 34 km), 48 rock-fall sites (length 31 km), and 5 debris-flow sites (length 0.14 km). In recent years the intensification of deformations was observed. For instance, during previous 10 years (1996¬¬-2005) 28 sudden deformations occurred due to slope processes, which caused interruptions in traffic. And in the present decade (2006-2015), 72 deformations were recorded. High landslide activity and economic loss determined the necessity of complex investigations of engineering geological conditions of landslides development and causes of its intensification. The protection strategy development was needed to minimize negative consequences. Thus, the investigations of landslide situation along the railway "Tuapse - Adler" included the categorization of landslide sites by level of hazard, with risk assessment based on numerical criteria. Preliminary evaluation of landslide hazard for the railway was conducted via the analysis of archived engineering-geological documents. 13 of 36 landslide sites (total length 13 km) were selected, reflecting the variety and peculiarities of landslide displacements on slopes (both active and inactive sites). Visual field observations of landslide slopes using drone "DJI Phantom 4" were completed during the second stage of this investigation. High-resolution photographs of landslide cirques, cracks, scarp walls, vegetation features were obtained via drone, which would have been impossible to obtain from the ground in conditions of dense subtropical vegetation cover. Possible approaches to the landslide activity and hazard assessment were evaluated: slope stability

  5. AschFlow - A dynamic landslide run-out model for medium scale hazard analysis.

    Science.gov (United States)

    Luna, Byron Quan; Blahut, Jan; van Asch, Theo; van Westen, Cees; Kappes, Melanie

    2015-04-01

    Landslides and debris flow hazard assessments require a scale-dependent analysis in order to mitigate damage and other negative consequences at the respective scales of occurrence. Medium or large scale landslide run-out modelling for many possible landslide initiation areas has been a cumbersome task in the past. This arises from the difficulty to precisely define the location and volume of the released mass and from the inability of the run-out models to compute the displacement with a large amount of individual initiation areas (computational exhaustive). Most of the existing physically based run-out models have complications in handling such situations and therefore empirical methods have been used as a practical mean to predict landslides mobility at a medium scale (1:10,000 to 1:50,000). In this context, a simple medium scale numerical model for rapid mass movements in urban and mountainous areas was developed. The deterministic nature of the approach makes it possible to calculate the velocity, height and increase in mass by erosion, resulting in the estimation of various forms of impacts exerted by debris flows at the medium scale The established and implemented model ("AschFlow") is a 2-D one-phase continuum model that simulates, the entrainment, spreading and deposition process of a landslide or debris flow at a medium scale. The flow is thus treated as a single phase material, whose behavior is controlled by rheology (e.g. Voellmy or Bingham). The developed regional model "AschFlow" was applied and evaluated in well documented areas with known past debris flow events.

  6. Landslide susceptibility mapping in Mawat area, Kurdistan Region, NE Iraq: a comparison of different statistical models

    Directory of Open Access Journals (Sweden)

    A. A. Othman

    2015-03-01

    Full Text Available During the last decades, expansion of settlements into areas prone to landslides in Iraq has increased the importance of accurate hazard assessment. Susceptibility mapping provides information about hazardous locations and thus helps to potentially prevent infrastructure damage due to mass wasting. The aim of this study is to evaluate and compare frequency ratio (FR, weight of evidence (WOE, logistic regression (LR and probit regression (PR approaches in combination with new geomorphological indices to determine the landslide susceptibility index (LSI. We tested these four methods in Mawat area, Kurdistan Region, NE Iraq, where landslides occur frequently. For this purpose, we evaluated 16 geomorphological, geological and environmental predicting factors mainly derived from the advanced spaceborne thermal emission and reflection radiometer (ASTER satellite. The available reference inventory includes 351 landslides representing a cumulative surface of 3.127 km2. This reference inventory was mapped from QuickBird data by manual delineation and partly verified by field survey. The areas under curve (AUC of the receiver operating characteristic (ROC, and relative landslide density (R index show that all models perform similarly and that focus should be put on the careful selection of proxies. The results indicate that the lithology and the slope aspects play major roles for landslide occurrences. Furthermore, this paper demonstrates that using hypsometric integral as a prediction factor instead of slope curvature gives better results and increases the accuracy of the LSI.

  7. Landslide susceptibility mapping in Mawat area, Kurdistan Region, NE Iraq: a comparison of different statistical models

    Science.gov (United States)

    Othman, A. A.; Gloaguen, R.; Andreani, L.; Rahnama, M.

    2015-03-01

    During the last decades, expansion of settlements into areas prone to landslides in Iraq has increased the importance of accurate hazard assessment. Susceptibility mapping provides information about hazardous locations and thus helps to potentially prevent infrastructure damage due to mass wasting. The aim of this study is to evaluate and compare frequency ratio (FR), weight of evidence (WOE), logistic regression (LR) and probit regression (PR) approaches in combination with new geomorphological indices to determine the landslide susceptibility index (LSI). We tested these four methods in Mawat area, Kurdistan Region, NE Iraq, where landslides occur frequently. For this purpose, we evaluated 16 geomorphological, geological and environmental predicting factors mainly derived from the advanced spaceborne thermal emission and reflection radiometer (ASTER) satellite. The available reference inventory includes 351 landslides representing a cumulative surface of 3.127 km2. This reference inventory was mapped from QuickBird data by manual delineation and partly verified by field survey. The areas under curve (AUC) of the receiver operating characteristic (ROC), and relative landslide density (R index) show that all models perform similarly and that focus should be put on the careful selection of proxies. The results indicate that the lithology and the slope aspects play major roles for landslide occurrences. Furthermore, this paper demonstrates that using hypsometric integral as a prediction factor instead of slope curvature gives better results and increases the accuracy of the LSI.

  8. Landslide monitoring in the Atlantic Highlands area, New Jersey

    Science.gov (United States)

    Reilly, Pamela A.; Ashland, Francis X.; Fiore, Alex R.

    2017-08-25

    Shallow and deep-seated landslides have occurred episodically on the steep coastal bluffs of the Atlantic Highlands area (Boroughs of Atlantic Highlands and Highlands) in New Jersey. The oldest documented deep-seated landslide occurred in April 1782 and significantly changed the morphology of the bluff. However, recent landslides have been mostly shallow in nature and have occurred during large storms with exceptionally heavy rainfall. These shallow landslides have resulted in considerable damage to residential property and local infrastructure and threatened human safety.The recent shallow landslides in the area (locations modified from New Jersey Department of Environmental Protection) consist primarily of slumps and flows of earth and debris within areas of historical landslides or on slopes modified by human activities. Such landslides are typically triggered by increases in shallow soil moisture and pore-water pressure caused by sustained and intense rainfall associated with spring nor’easters and late summer–fall tropical cyclones. However, the critical relation between rainfall, soil-moisture conditions, and landslide movement has not been fully defined. The U.S. Geological Survey is currently monitoring hillslopes within the Atlantic Highlands area to better understand the hydrologic and meteorological conditions associated with shallow landslide initiation.

  9. Using geotypes for landslide hazard assessment and mapping: a coupled field and GIS-based method

    Science.gov (United States)

    Bilgot, S.; Parriaux, A.

    2009-04-01

    Switzerland is exceptionally subjected to landslides; indeed, about 10% of its area is considered as unstable. Making this observation, its Department of the Environment (BAFU) introduces in 1997 a method to realize landslide hazard maps. It is routinely used but, like most of the methods applied in Europe to map unstable areas, it is mainly based on the signs of previous or current phenomena (geomorphologic mapping, archive consultation, etc.) even though instabilities can appear where there is nothing to show that they existed earlier. Furthermore, the transcription from the geomorphologic map to the hazard map can vary according to the geologist or the geographer who realizes it: this method is affected by a certain lack of transparency. The aim of this project is to introduce the bedrock of a new method for landslide hazard mapping; based on instability predisposition assessment, it involves the designation of main factors for landslide susceptibility, their integration in a GIS to calculate a landslide predisposition index and the implementation of new methods to evaluate these factors; to be competitive, these processes have to be both cheap and quick. To identify the most important parameters to consider for assessing slope stability, we chose a large panel of topographic, geomechanic and hydraulic parameters and tested their importance by calculating safety factors on theoretical landslides using Geostudio 2007®; thus, we could determine that slope, cohesion, hydraulic conductivity and saturation play an important role in soil stability. After showing that cohesion and hydraulic conductivity of loose materials are strongly linked to their granulometry and plasticity index, we implemented two new field tests, one based on teledetection and one coupled sedimentometric and blue methylen test to evaluate these parameters. From these data, we could deduce approximated values of maximum cohesion and saturated hydraulic conductivity. The hydraulic conductivity of

  10. Modelling landslide hazard, soil redistribution and sediment yield of landslides on the Ugandan footslopes of Mount Elgon

    NARCIS (Netherlands)

    Claessens, L.; Knapen, A.; Kitutu, M.G.; Poesen, J.; Deckers, J.A.

    2007-01-01

    In this study, the LAPSUS-LS landslide model, together with a digital terrain analysis of topographic attributes, is used as a spatially explicit tool to simulate recent shallow landslides in Manjiya County on the Ugandan slopes of Mount Elgon. Manjiya County is a densely populated mountainous area

  11. Comparative Assessment of Three Nonlinear Approaches for Landslide Susceptibility Mapping in a Coal Mine Area

    Directory of Open Access Journals (Sweden)

    Qiaomei Su

    2017-07-01

    Full Text Available Landslide susceptibility mapping is the first and most important step involved in landslide hazard assessment. The purpose of the present study is to compare three nonlinear approaches for landslide susceptibility mapping and test whether coal mining has a significant impact on landslide occurrence in coal mine areas. Landslide data collected by the Bureau of Land and Resources are represented by the X, Y coordinates of its central point; causative factors were calculated from topographic and geologic maps, as well as satellite imagery. The five-fold cross-validation method was adopted and the landslide/non-landslide datasets were randomly split into a ratio of 80:20. From this, five subsets for 20 times were acquired for training and validating models by GIS Geostatistical analysis methods, and all of the subsets were employed in a spatially balanced sample design. Three landslide models were built using support vector machine (SVM, logistic regression (LR, and artificial neural network (ANN models by selecting the median of the performance measures. Then, the three fitted models were compared using the area under the receiver operating characteristics (ROC curves (AUC and the performance measures. The results show that the prediction accuracies are between 73.43% and 87.45% in the training stage, and 67.16% to 73.13% in the validating stage for the three models. AUCs vary from 0.807 to 0.906 and 0.753 to 0.944 in the two stages, respectively. Additionally, three landslide susceptibility maps were obtained by classifying the range of landslide probabilities into four classes representing low (0–0.02, medium (0.02–0.1, high (0.1–0.85, and very high (0.85–1 probabilities of landslides. For the distributions of landslide and area percentages under different susceptibility standards, the SVM model has more relative balance in the four classes compared to the LR and the ANN models. The result reveals that the SVM model possesses better

  12. Hazard analysis of landslides triggered by Typhoon Chata'an on July 2, 2002, in Chuuk State, Federated States of Micronesia

    Science.gov (United States)

    Harp, Edwin L.; Reid, Mark E.; Michael, John A.

    2004-01-01

    More than 250 landslides were triggered across the eastern volcanic islands of Chuuk State in the Federated States of Micronesia by torrential rainfall from tropical storm Chata?an on July 2, 2002. Landslides triggered during nearly 20 inches of rainfall in less than 24 hours caused 43 fatalities and the destruction or damage of 231 structures, including homes, schools, community centers, and medical dispensaries. Landslides also buried roads, crops, and water supplies. The landslides ranged in volume from a few cubic meters to more than 1 million cubic meters. Most of the failures began as slumps and transformed into debris flows, some of which traveled several hundred meters across coastal flatlands into populated areas. A landslide-inventory map produced after the storm shows that the island of Tonoas had the largest area affected by landslides, although the islands of Weno, Fefan, Etten, Uman, Siis, Udot, Eot, and Fanapanges also had significant landslides. Based on observations since the storm, we estimate the continuing hazard from landslides triggered by Chata?an to be relatively low. However, tropical storms and typhoons similar to Chata?an frequently develop in Micronesia and are likely to affect the islands of Chuuk in the future. To assess the landslide hazard from future tropical storms, we produced a hazard map that identifies landslide-source areas of high, moderate, and low hazard. This map can be used to identify relatively safe areas for relocating structures or establishing areas where people could gather for shelter in relative safety during future typhoons or tropical storms similar to Chata?an.

  13. Shallow Landslide Susceptibility Mapping for Selected Areas in the Philippines Severely affected by Super Typhoon Haiyan

    Science.gov (United States)

    Felix, Raquel; Rabonza, Maricar; Ortiz, Iris Jill; Alejandrino, Ian Kaye; Aquino, Dakila; Narod Eco, Rodrigo; Mahar Francisco Lagmay, Alfredo

    2014-05-01

    Super Typhoon Haiyan, considered as one of the most powerful storms recorded in 2013, devastated the central Philippines region on 8 November 2013. In its wake, Haiyan left 6,190 fatalities, 28,626 injured and 1,785 missing, as well as damage amounting to more than USD 823 million. To mitigate damage from similar events in the future, it is imperative to characterize hazards associated with tropical cyclones such as those brought by Haiyan, with detailed studies of storm surges, landslides and floods. Although strong winds and powerful storm surges up 15-17 feet were the primary causes of damage, landslides studies are also vital in the rehabilitation of typhoon damaged areas. Cities and municipalities of Leyte (7,246.7 sq. km) and Samar (13,121 sq. km) provinces, the heaviest cities area during the onslaught of Haiyan, require detailed and up-to-date hazard maps for their rebuilding and disaster mitigation programs. In order to delineate areas susceptible to rainfall induced shallow landslides, Stability INdex MAPping (SINMAP) software was used over a 6-meter Synthetic Aperture Radar (SAR)-derived DEM grid. Soil calibration parameters from previous studies were used as parameter input to generate a worst-case scenario hazard map of the two provinces. Topographic, hydrologic and soil parameters (cohesion, angle of friction, bulk density and hydraulic conductivity) were used for each pixel of a given digital elevation model (DEM) grid to compute for the corresponding factor of safety. The landslide maps generated using SINMAP are found to be consistent with the landslide inventory derived from high-resolution satellite imagery 2003-2013. The landslide susceptibility classification found in the landslide hazard maps are useful to identify no-build zones, areas that can be built upon but with slope intervention and monitoring as well as places that are safe from shallow landslides. These maps complement the debris flow and structurally-controlled landslide hazard maps

  14. Risk analysis for roadways subjected to multiple landslide-related hazards

    Science.gov (United States)

    Corominas, Jordi; Mavrouli, Olga

    2014-05-01

    Roadways through mountainous terrain often involve cuts and landslide areas whose stability is precarious and require protection and stabilization works. To optimize the allocation of resources, government and technical offices are increasingly interested in both the risk analysis and assessment. Risk analysis has to consider the hazard occurrence and the consequences. The consequences can be both direct and indirect. The former include the costs regarding the repair of the roadway, the damage of vehicles and the potential fatalities, while the latter refer to the costs related to the diversion of vehicles, the excess of distance travelled, the time differences, and tolls. The type of slope instabilities that may affect a roadway may vary and its effects as well. Most current approaches either consider a single hazardous phenomenon each time, or if applied at small (for example national) scale, they do not take into account local conditions at each section of the roadway. The objective of this work is the development of a simple and comprehensive methodology for the assessment of the risk due to multiple hazards along roadways, integrating different landslide types that include rockfalls, debris flows and considering as well the potential failure of retaining walls. To quantify risk, all hazards are expressed with a common term: their probability of occurrence. The methodology takes into consideration the specific local conditions along the roadway. For rockfalls and debris flow a variety of methods for assessing the probability of occurrence exists. To assess the annual probability of failure of retaining walls we use an indicator-based model that provides a hazard index. The model parameters consist in the design safety factor, and further anchorage design and construction parameters. The probability of failure is evaluated in function of the hazard index and next corrected (in terms of order of magnitude) according to in situ observations for increase of two

  15. Combining computational models for landslide hazard assessment of Guantánamo province, Cuba

    NARCIS (Netherlands)

    Castellanos Abella, E.A.

    2009-01-01

    As part of the Cuban system for landslide disaster management, a methodology was developed for regional scale landslide hazard assessment, which is a combination of different models. The method was applied in Guantánamo province at 1:100 000 scale. The analysis started with an extensive aerial photo

  16. Combining computational models for landslide hazard assessment of Guantánamo province, Cuba

    NARCIS (Netherlands)

    Castellanos Abella, E.A.

    2008-01-01

    As part of the Cuban system for landslide disaster management, a methodology was developed for regional scale landslide hazard assessment, which is a combination of different models. The method was applied in Guantánamo province at 1:100 000 scale. The analysis started with an extensive aerial

  17. Geospatial Approach on Landslide Hazard Zonation Mapping Using Multicriteria Decision Analysis: A Study on Coonoor and Ooty, Part of Kallar Watershed, The Nilgiris, Tamil Nadu

    Science.gov (United States)

    Rahamana, S. Abdul; Aruchamy, S.; Jegankumar, R.

    2014-12-01

    Landslides are one of the critical natural phenomena that frequently lead to serious problems in hilly area, resulting to loss of human life and property, as well as causing severe damage to natural resources. The local geology with high degree of slope coupled with high intensity of rainfall along with unplanned human activities of the study area causes many landslides in this region. The present study area is more attracted by tourist throughout the year, so this area must be considered for preventive measures. Geospatial based Multicriteria decision analysis (MCDA) technique is increasingly used for landslide vulnerability and hazard zonation mapping. It enables the integration of different data layers with different levels of uncertainty. In this present study, it is used analytic hierarchy process (AHP) method to prepare landslide hazard zones of the Coonoor and Ooty, part of Kallar watershed, The Nilgiris, Tamil Nadu. The study was carried out using remote sensing data, field surveys and geographic information system (GIS) tools. The ten factors that influence landslide occurrence, such as elevation, slope aspect, slope angle, drainage density, lineament density, soil, precipitation, land use/land cover (LULC), distance from road and NDVI were considered. These factors layers were extracted from the various related spatial data's. These factors were evaluated, and then, the individual factor weight and class weight were assigned to each of the related factors. The Landslide Hazard Zone Index (LHZI) was calculated using Multicriteria decision analysis (MCDA) the technique based on the assigned weight and the rating is given by the Analytical Hierarchy Process (AHP) method. The final cumulative map of the study area was categorized into four hazard zones and classified as zone I to IV. There are 3.56% of the area comes under the hazard zone IV fallowed by 48.19% of the area comes under zone III, 43.63 % of the area in zone II and 4.61% of the area comes hazard

  18. FEMA DFIRM Flood Hazard Areas

    Data.gov (United States)

    Minnesota Department of Natural Resources — FEMA flood hazard delineations are used by the Federal Emergency Management Agency (FEMA) to designate the Special Flood Hazard Area (SFHA) and for insurance rating...

  19. A new concept in seismic landslide hazard analysis for practical application

    Science.gov (United States)

    Lee, Chyi-Tyi

    2017-04-01

    A seismic landslide hazard model could be constructed using deterministic approach (Jibson et al., 2000) or statistical approach (Lee, 2014). Both approaches got landslide spatial probability under a certain return-period earthquake. In the statistical approach, our recent study found that there are common patterns among different landslide susceptibility models of the same region. The common susceptibility could reflect relative stability of slopes at a region; higher susceptibility indicates lower stability. Using the common susceptibility together with an earthquake event landslide inventory and a map of topographically corrected Arias intensity, we can build the relationship among probability of failure, Arias intensity and the susceptibility. This relationship can immediately be used to construct a seismic landslide hazard map for the region that the empirical relationship built. If the common susceptibility model is further normalized and the empirical relationship built with normalized susceptibility, then the empirical relationship may be practically applied to different region with similar tectonic environments and climate conditions. This could be feasible, when a region has no existing earthquake-induce landslide data to train the susceptibility model and to build the relationship. It is worth mentioning that a rain-induced landslide susceptibility model has common pattern similar to earthquake-induced landslide susceptibility in the same region, and is usable to build the relationship with an earthquake event landslide inventory and a map of Arias intensity. These will be introduced with examples in the meeting.

  20. Analysis of shallow landslides and soil erosion induced by rainfall over large areas

    Science.gov (United States)

    Cuomo, Sabatino; Della Sala, Maria

    2014-05-01

    Due to heavy rainstorms, steep hillslopes may be affected by either shallow landslides or soil superficial erosion (Acharya et al., 2011), which originate different flow-like mass movements in adjacent or overlapping source areas (Cascini et al., 2013). Triggering analysis (Cascini et al., 2011) is a relevant issue for hazard assessment that is, in turn, the first step of risk analysis procedures (Fell et al., 2008). Nevertheless, the available approaches separately consider shallow landslides and soil erosion. Specifically, quantitative models for landslides triggering analysis allow simulating the physical processes leading to failure such as pore water pressure increase and soil shear mobilization and provide estimates of the amount of material potentially involved; however, success of quantitative methods must be carefully evaluated in complex geological setting as recently outlined (Sorbino et al., 2010) and further applications to real case histories are straightforward. On the other hand, a wide range of models exist for soil erosion analysis, which differ in terms of complexity, processes considered and data required for the model calibration and practical applications; in particular, quantitative models can estimate the source areas and the amount of eroded soil through empirical relationships or mathematical equations describing the main physical processes governing soil erosion (Merritt et al., 2003). In this work a spatially distributed analysis is proposed for testing the potentialities of two available models to respectively investigate the spatial occurrence of first-time shallow landslides and superficial soil erosion repeatedly occurring in a large test area of the Southern Italy. Both analyses take into account the seasonal variation of soil suction, rainfall characteristics and soil cover use (Cuomo and Della Sala, 2013). The achieved results show that the source areas of shallow landslides strongly depend on rainfall intensity and duration and

  1. Using Remotely Sensed Information for Near Real-Time Landslide Hazard Assessment

    Science.gov (United States)

    Kirschbaum, Dalia; Adler, Robert; Peters-Lidard, Christa

    2013-01-01

    The increasing availability of remotely sensed precipitation and surface products provides a unique opportunity to explore how landslide susceptibility and hazard assessment may be approached at larger spatial scales with higher resolution remote sensing products. A prototype global landslide hazard assessment framework has been developed to evaluate how landslide susceptibility and satellite-derived precipitation estimates can be used to identify potential landslide conditions in near-real time. Preliminary analysis of this algorithm suggests that forecasting errors are geographically variable due to the resolution and accuracy of the current susceptibility map and the application of satellite-based rainfall estimates. This research is currently working to improve the algorithm through considering higher spatial and temporal resolution landslide susceptibility information and testing different rainfall triggering thresholds, antecedent rainfall scenarios, and various surface products at regional and global scales.

  2. A landslide susceptibility assessment in urban areas based on existing data: an example from the Iguaná Valley, Medellín City, Colombia

    Directory of Open Access Journals (Sweden)

    J. Klimeš

    2010-10-01

    Full Text Available Fast urbanization and the morphological conditions of the Iguaná River Basin, Medellín, Colombia have forced many people to settle on landslide prone slopes as evidenced by extensive landslide induced damage. In this study we used existing disaster databases (inventories in order to examine the spatial and temporal variability of landsliding within this watershed. The spatial variability of landsliding was examined using "expert-based" and "weighted" landslide susceptibility models. The constructed landslide susceptibility maps demonstrate consistent results irrespective of the underlying method. These show that at least 55.9% of the watershed is highly or very highly susceptible to landsliding. In addition, the temporal distribution of landsliding was analyzed and compared with climatic data. Results show that the area has a distinct bimodal rainfall distribution, and it is clear that landsliding is particularly frequent during the later rainy season between October and November. Moreover, landslides are more common during La Niña years. It is recommended that the existing landslide inventories are improved so as to be of greater use in the future land use planning of the watershed. The construction of landslide susceptibility maps based on existing data represents a significant step towards landslide mitigation in the area. Using susceptibility and hazard assessment during the developmental process should lessen the need for disaster response at a later stage.

  3. The contribution of PSInSAR interferometry to landslide susceptibility assessment in weak rock-dominated areas

    Science.gov (United States)

    Oliveira, Sérgio C.; Zêzere, José L.; Catalão, João; Nico, Giovanni

    2015-04-01

    In the Grande da Pipa river basin (north of Lisbon, Portugal), 64% of the landslides inventoried occur on a particular weak rock lithological unit composed by clay and with sandstone intercalations, that is present in 58% of the study (Oliveira et al., 2014). Deep-seated slow moving rotational slides occur essentially on this lithological unit and are responsible for the major damages verified along roads and buildings in the study area. Within this context, landslide hazard assessment, is limited by two major constrains: (i) the slope instability signs may not be sufficiently clear and observable and consequently may not be correctly identifiable through traditional geomorphologic survey techniques and (ii) the non-timely recognition of precursor signs of instability both in landslides activated for the first time and in previously landslide-affected areas (landslide reactivation). To encompass these limitations, the Persistent Scatterer synthetic aperture radar interferometry technique is applied to a data set of 16 TerraSAR-X SAR images, from April of 2010 to March of 2011, available for a small test site of 12.5 square kilometers (Laje-Salema) located on south-central part of the study area. This work's specific objectives are the following: (i) to evaluate the capacity of the Persistent Scatterer displacement maps in assessing landslide susceptibility at the regional scale, and (ii) to assess the capacity of landslide susceptibility maps based on historical landslide inventories to predict the location of actual terrain displacement measured by the Persistent Scatterers technique. Landslide susceptibility was assessed for the test site using the Information Value bivariate statistical method and the susceptibility scores were exported to the Grande da Pipa river basin. The independent validation of the landslide susceptibility maps was made using the historical landslide inventory and the Persistent Scatterer displacement map. Results are compared by computing

  4. GIS-Based and Data-Driven Bivariate Landslide-Susceptibility Mapping in the Three Gorges Area, China

    Institute of Scientific and Technical Information of China (English)

    BAI Shi-Biao; WANG Jian; L(U) Guo-Nian; ZHOU Ping-Gen; HOU Sheng-Shan; XU Su-Ning

    2009-01-01

    A detailed landslide-susceptibility map was produced using a data-driven objective bivariate analysis method with datasets developed for a geographic information system (CIS). Known as one of the most landslide-prone areas in China, the Zhongxian-Shizhu Segment in the Three Gorges Reservoir region of China was selected as a suitable case because of the frequency and distribution of landslides. The site covered an area of 260.93 km2 with a landslide area of 5.32 km2. Four data domains were used in this study, including remote sensing products, thematic maps, geological maps, and topographical maps, all with 25 m × 25 m pixels. Statistical relationships for landslide susceptibility were developed using landslide and landslide causative factor databases. All continuous variables were converted to categorical variables according to the percentile divisions of seed cells, and the corresponding class weight values were calculated and summed to create the susceptibility map. According to the map, 3.6% of the study area was identified as high-susceptibility. Extremely low-, very low-, low-, and medium-susceptibility zones covered 19.66%, 31.69%, 27.95%, and 17.1% of the area, respectively. The high- and medium-hazardous zones are along both sides of the Yangtze River, being in agreement with the actual distribution of landslides.

  5. Assessing rainfall triggered landslide hazards through physically based models under uncertainty

    Science.gov (United States)

    Balin, D.; Metzger, R.; Fallot, J. M.; Reynard, E.

    2009-04-01

    Hazard and risk assessment require, besides good data, good simulation capabilities to allow prediction of events and their consequences. The present study introduces a landslide hazards assessment strategy based on the coupling of hydrological physically based models with slope stability models that should be able to cope with uncertainty of input data and model parameters. The hydrological model used is based on the Water balance Simulation Model, WASIM-ETH (Schulla et al., 1997), a fully distributed hydrological model that has been successfully used previously in the alpine regions to simulate runoff, snowmelt, glacier melt, and soil erosion and impact of climate change on these. The study region is the Vallon de Nant catchment (10km2) in the Swiss Alps. A sound sensitivity analysis will be conducted in order to choose the discretization threshold derived from a Laser DEM model, to which the hydrological model yields the best compromise between performance and time computation. The hydrological model will be further coupled with slope stability methods (that use the topographic index and the soil moisture such as derived from the hydrological model) to simulate the spatial distribution of the initiation areas of different geomorphic processes such as debris flows and rainfall triggered landslides. To calibrate the WASIM-ETH model, the Monte Carlo Markov Chain Bayesian approach is privileged (Balin, 2004, Schaefli et al., 2006). The model is used in a single and a multi-objective frame to simulate discharge and soil moisture with uncertainty at representative locations. This information is further used to assess the potential initial areas for rainfall triggered landslides and to study the impact of uncertain input data, model parameters and simulated responses (discharge and soil moisture) on the modelling of geomorphological processes.

  6. Linking rainfall-induced landslides with debris flows runout patterns towards catchment scale hazard assessment

    Science.gov (United States)

    Fan, Linfeng; Lehmann, Peter; McArdell, Brian; Or, Dani

    2017-03-01

    Debris flows and landslides induced by heavy rainfall represent an ubiquitous and destructive natural hazard in steep mountainous regions. For debris flows initiated by shallow landslides, the prediction of the resulting pathways and associated hazard is often hindered by uncertainty in determining initiation locations, volumes and mechanical state of the mobilized debris (and by model parameterization). We propose a framework for linking a simplified physically-based debris flow runout model with a novel Landslide Hydro-mechanical Triggering (LHT) model to obtain a coupled landslide-debris flow susceptibility and hazard assessment. We first compared the simplified debris flow model of Perla (1980) with a state-of-the art continuum-based model (RAMMS) and with an empirical model of Rickenmann (1999) at the catchment scale. The results indicate that predicted runout distances by the Perla model are in reasonable agreement with inventory measurements and with the other models. Predictions of localized shallow landslides by LHT model provides information on water content of released mass. To incorporate effects of water content and flow viscosity as provided by LHT on debris flow runout, we adapted the Perla model. The proposed integral link between landslide triggering susceptibility quantified by LHT and subsequent debris flow runout hazard calculation using the adapted Perla model provides a spatially and temporally resolved framework for real-time hazard assessment at the catchment scale or along critical infrastructure (roads, railroad lines).

  7. Flood Hazard Area

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  8. Examining the impact of landslide disturbances on hydrologic response dynamics using a paired hillslope approach: Implications for landslide hazard persistence

    Science.gov (United States)

    Mirus, B. B.; Smith, J. B.; Baum, R. L.

    2016-12-01

    Landslides not only alter hillslope topography, but also change the hydrologic storage capacity and flow path connectivity within the subsurface. Influences of this disturbance on hydrology and resulting susceptibility to subsequent landsliding remain poorly understood. Since landslides often occur at the site of previous slope failures, we examined differences in hydrologic response between a vegetated hillslope (VH) and an active landslide hillslope (LH) using continuous monitoring of rainfall and subsurface pore pressures and saturation. These paired hillslopes are situated 0.5 km apart on steep coastal bluffs of heterogeneous glacial outwash deposits along the northeastern shore of Puget Sound, Washington. The average slopes of VH and LH are comparable (35 and 32°, respectively), the total relief of the bluffs is the same (42 m), and our field observations suggest that glacial deposits underlying both slopes are similar (mix of cobbles, gravel, sand, slits, and clays). The VH is mantled by a thin layer of sandy-silty colluvium and supports a dense forest. In early 2013 the LH also supported a dense forest, at which time a major slope failure substantially altered the topography, vegetation pattern, and regolith material. In 2015 we observed a clay-rich landslide deposit at the LH, with sparse vegetation. Findings from our 2015-2016 monitoring include: (1) lower cumulative rainfall at the VH, due to canopy interception, (2) earlier winter transition to wet, near-saturated conditions at the LH, (3) longer persistence of positive pore pressures at the LH between major storm events, and (4) episodic, complex failures at the LH, such as block falls from the headscarp, translational slides, and mudflows on lower portions of the deposit. These observed differences between the hillslopes support the hypothesis that disturbances introduced by landsliding may promote the hydrologic conditions contributing to slope instability and the persistence of landslide hazards.

  9. Digital elevation models in the marine domain: investigating the offshore tsunami hazard from submarine landslides

    Science.gov (United States)

    Tappin, David R.

    2015-04-01

    Over the past 30 years multibeam bathymetry has replaced single-beam echo soundings as the main tool used to map the sea floor. Developed as a military tool its expansion into the scientific domain has revolutionized our ability not only to visualise seabed morphology, but also to interpret the active processes taking place at and beneath the seabed. DEMs derived from multibeam are now comparable to those on land. One aspect of the improved seabed visualization is in mapping marine geohazards, in this instance, submarine landslides. One of the first multibeam surveys actually programmed to investigate an actual event was in 1999 after the tsunami on the north coast of Papua New Guinea killed 2,200 people. It was a wake-up call, as the relatively small magnitude earthquake - 7.1 - could not generate tsunami waves up to 15m high at the coast. The submarine slump was clearly visible on the multibeam and associated seabed sampling confirmed that it was a recent event. Subsequent research proved that the landslide generated the tsunami as, again for the first time the multibeam was used as the basis for the tsunami simulations. Since 1999 many submarine landslides have been mapped, but not all have an associated identified tsunami. Some landslides are associated with earthquakes and this causes confusion if there is an anomalously large tsunami for example Alaska, 1946 and Java, 2006. Others are suspected of causing a tsunami, but their evidence on the seabed is hard to identify as with Messina, 1908. The most confusing recent tsunami event has been 2011 Japan tsunami, where a submarine landslide to the north of the main rupture is almost certainly responsible for the 40m high coastal waves that struck northern Honshu. The seabed has now been mapped on a broadscale by satellite gravity, but maps from this method cannot identify any but the largest seabed morphologies; most submarine landslides cannot therefore be recognised. Large seabed areas still remain unmapped to

  10. Subaqueous landslides at the distal basin of Lago Nahuel Huapi (Argentina): Towards a tsunami hazard evaluation in Northern Patagonian lakes

    Science.gov (United States)

    Beigt, Débora; Villarosa, Gustavo; Gómez, Eduardo A.; Manzoni, Carolina

    2016-09-01

    The May 22nd, 1960 Valdivia earthquake, Chile (Mw 9.5) triggered a series of subaqueous mass-wasting processes (debris flows and slides) in Lago Nahuel Huapi (Argentina), generating a tsunami-like wave that hit the coasts of San Carlos de Bariloche. Aiming to provide a first preliminary insight into tsunami hazards for the lakeshore communities, in this paper we identify and characterize the subaqueous landslides at the populated distal basin of the lake. Swath bathymetric and seismic profiling surveys were carried out and high-resolution digital elevation models were derived from these data to perform a landslide inventory map. A series of morphometrical parameters (including the landslide area, the volume of displaced materials and the run-out distance, among others) were estimated upon selected events. The results indicated that landslide activity at the distal basin of Lago Nahuel Huapi has been concentrated in the vicinity of Bariloche (massive landslide triggered by the 1960 earthquake) and within steep delta fronts where the slope failures typically initiate at shallow waters (9-11 m depth). The sliding mass frequently travels basinward along a great distance (≥ 1000 m). At the delta fronts, the volume of material removed by landslides can reach ~ 40 × 104 m3, leaving scar areas of up to 13 m thick. The periodic occurrence of rotational-translational mass movements initiating at the upper edge of the delta fronts, with vertical displacements of the mobilized materials reaching ~ 200 m, probably represents a potential tsunami hazard for the nearby populated coasts.

  11. Application of a time probabilistic approach to seismic landslide hazard estimates in Iran

    Science.gov (United States)

    Rajabi, A. M.; Del Gaudio, V.; Capolongo, D.; Khamehchiyan, M.; Mahdavifar, M. R.

    2009-04-01

    the slope critical acceleration (Ac)x for which a prefixed probability exists that seismic shaking would result in a Dn value equal to a threshold x whose exceedence would cause landslide triggering. The obtained ac values represent the minimum slope resistance required to keep the probability of seismic-landslide triggering within the prefixed value. In particular we calculated the spatial distribution of (Ac)x for x thresholds of 10 and 2 cm in order to represent triggering conditions for coherent slides (e.g., slumps, block slides, slow earth flows) and disrupted slides (e.g., rock falls, rock slides, rock avalanches), respectively. Then we produced a probabilistic national map that shows the spatial distribution of (Ac)10 and (Ac)2, for a 10% probability of exceedence in 50 year, which is a significant level of hazard equal to that commonly used for building codes. The spatial distribution of the calculated (Ac)xvalues can be compared with the in situ actual ac values of specific slopes to estimate whether these slopes have a significant probability of failing under seismic action in the future. As example of possible application of this kind of time probabilistic map to hazard estimates, we compared the values obtained for the Manjil region with a GIS map providing spatial distribution of estimated ac values in the same region. The spatial distribution of slopes characterized by ac < (Ac)10 was then compared with the spatial distribution of the major landslides of coherent type triggered by the Manjil earthquake. This comparison provides indications on potential, problems and limits of the experimented approach for the study area. References Cornell, C.A., 1968: Engineering seismic risk analysis, Bull. Seism. Soc. Am., 58, 1583-1606. Del Gaudio V., Wasowski J., & Pierri P., 2003: An approach to time probabilistic evaluation of seismically-induced landslide hazard. Bull Seism. Soc. Am., 93, 557-569. Jibson, R.W., E.L. Harp and J.A. Michael, 1998: A method for

  12. Use of High Resolution LiDAR imagery for landslide identification and hazard assessment, State Highway 6, Haast Pass, New Zealand

    Science.gov (United States)

    Walsh, Andrew; Zimmer, Valerie; Bell, David

    2015-04-01

    This study has assessed landslide hazards associated with steep and densely vegetated bedrock slopes adjacent to State Highway 6 through the Southern Alps of New Zealand. The Haast Pass serves as one of only three routes across the Southern Alps, and is a lifeline to the southern West Coast of the South Island with a 1,000km detour required through the nearest alternative pass. Over the last 50 years the highway has been subjected to numerous landslide events that have resulted in lengthy road closures, and the death of two tourists in September 2013. To date no study has been undertaken to identify and evaluate the landslide hazards for the entire Haast Pass, with previous work focusing on post-failure monitoring or investigation of individual landslides. This study identified the distribution and extent of regolith deposits on the schist slopes, and the location and sizes of dormant and active landslides potentially impacting the highway. Until the advent of LiDAR technology it had not been possible to achieve such an evaluation because dense vegetation and very steep topography prevented traditional methods of investigation (mapping; trenching; drilling; geophysics) from being used over a large part of the area. LiDAR technology has provided the tools with which to evaluate large areas of the slopes above the highway quickly and with great accuracy. A very high resolution LiDAR survey was undertaken with a flight line overlap of 70%, resulting in six points per square metre in the raw point cloud and a post-processing point spacing of half a metre. The point cloud was transformed into a digital terrain model, and the surface interpreted using texture and morphology to identify slope materials and landslides. Analysis of the LiDAR DTM revealed that the slopes above the highway consist of variable thicknesses of regolith sourced from landsliding events, as well as large areas of bare bedrock that have not been subjected to landslides and that pose minimal hazard

  13. Extending natural hazard impacts: an assessment of landslide disruptions on a national road transportation network

    Science.gov (United States)

    Postance, Benjamin; Hillier, John; Dijkstra, Tom; Dixon, Neil

    2017-01-01

    Disruptions to transportation networks by natural hazard events cause direct losses (e.g. by physical damage) and indirect socio-economic losses via travel delays and decreased transportation efficiency. The severity and spatial distribution of these losses varies according to user travel demands and which links, nodes or infrastructure assets are physically disrupted. Increasing transport network resilience, for example by targeted mitigation strategies, requires the identification of the critical network segments which if disrupted would incur undesirable or unacceptable socio-economic impacts. Here, these impacts are assessed on a national road transportation network by coupling hazard data with a transport network model. This process is illustrated using a case study of landslide hazards on the road network of Scotland. A set of possible landslide-prone road segments is generated using landslide susceptibility data. The results indicate that at least 152 road segments are susceptible to landslides, which could cause indirect economic losses exceeding £35 k for each day of closure. In addition, previous estimates for historic landslide events might be significant underestimates. For example, the estimated losses for the 2007 A83 ‘Rest and Be Thankful’ landslide are £80 k day-1, totalling £1.2 million over a 15 day closure, and are ˜60% greater than previous estimates. The spatial distribution of impact to road users is communicated in terms of ‘extended hazard impact footprints’. These footprints reveal previously unknown exposed communities and unanticipated spatial patterns of severe disruption. Beyond cost-benefit analyses for landslide mitigation efforts, the approach implemented is applicable to other natural hazards (e.g. flooding), combinations of hazards, or even other network disruption events.

  14. Earthquake induced landslide hazard: a multidisciplinary field observatory in the Marmara SUPERSITE

    Science.gov (United States)

    Bigarré, Pascal

    2014-05-01

    Earthquake-triggered landslides have an increasing disastrous impact in seismic regions due to the fast growing urbanization and infrastructures. Just considering disasters from the last fifteen years, among which the 1999 Chi-Chi earthquake, the 2008 Wenchuan earthquake, and the 2011 Tohoku earthquake, these events generated tens of thousands of coseismic landslides. Those resulted in amazing death toll and considerable damages, affecting the regional landscape including its hydrological main features. Despite a strong impetus in research during past decades, knowledge on those geohazards is still fragmentary, while databases of high quality observational data are lacking. These phenomena call for further collaborative researches aiming eventually to enhance preparedness and crisis management. As one of the three SUPERSITE concept FP7 projects dealing with long term high level monitoring of major natural hazards at the European level, the MARSITE project gathers research groups in a comprehensive monitoring activity developed in the Sea of Marmara Region, one of the most densely populated parts of Europe and rated at high seismic risk level since the 1999 Izmit and Duzce devastating earthquakes. Besides the seismic threat, landslides in Turkey and in this region constitute an important source of loss. The 1999 Earthquake caused extensive landslides while tsunami effects were observed during the post-event surveys in several places along the coasts of the Izmit bay. The 6th Work Package of MARSITE project gathers 9 research groups to study earthquake-induced landslides focusing on two sub-regional areas of high interest. First, the Cekmece-Avcilar peninsula, located westwards of Istanbul, is a highly urbanized concentrated landslide prone area, showing high susceptibility to both rainfalls while affected by very significant seismic site effects. Second, the off-shore entrance of the Izmit Gulf, close to the termination of the surface rupture of the 1999 earthquake

  15. application of geospatial tools for landslide hazard assessment for ...

    African Journals Online (AJOL)

    immax

    landslide causal factors such as slope, precipitation, soil texture, vegetation cover and .... acquired from the Uganda Bureau of Statistics (UBOS), the land cover ... Meteorological Centre, while the Digital Elevation Model was acquired from the ...

  16. Towards a National Hazard Map of Landslides: Juan de Grijalva, Chiapas, and Mitlatongo, Oaxaca, two catastrophic landslides on southeastern of Mexico

    Science.gov (United States)

    Dominguez-M, L.; Castañeda, A.; Ramirez, A.; González, A. E.

    2013-05-01

    One of the most catastrophic events, with economical losses and deaths, in Mexico and Latin America, is the landslide event. The Juan de Grijalva landslide, which blocked one of the largest rivers in the Chiapas state of Mexico, on November 4, 2007, is considered one of the greatest that have occurred in the world in the last 100 years (Dominguez, 2008) and it could be the one with the largest economic impact in the history of Mexico. This landslide occurred four days after a period of very heavy rains that caused, in the peak of the emergency, flooding in almost 62% of the area of the state of Tabasco (CENAPRED, 2009) and is also one of the most serious disasters that were faced by the Mexican government in the past 10 years. The Juan de Grijalva landslide mobilized the entire government apparatus and required an investment of just over 0.1 billions of US Dollars (CENAPRED, 2009) for the rehabilitation of the river runway and additional works in order to prevent further damages if another landslide occurs in the vicinity. A similar case of interest for Mexican researchers and specialists in earth sciences is the big landslide occurred in the communities of Santa Cruz Mitlatongo, municipality of Magdalena Jaltepec, and Santiago Mitlatongo, municipality of Nochixtlan, both in the state of Oaxaca (Dominguez, 2011). This landslide has dimensions of just over 2,500 m long and 900 m wide, and it remains active from September 2011. Since then, the landslide has moved just over 230 m in length and has destroyed about 850 houses. Given the geological and geotechnical characteristics of these landslides and the economic and social impact caused, the National Center for Disaster Prevention (CENAPRED) has initiated a research project in order to learn the main factors (constraints and triggers) that influenced both landslides. In relation with the National Hazard Landslide Map, developed by CENAPRED, these events are an important task of the National Inventory of Landslides

  17. Urban and Rural Landslide Hazard and Exposure Mapping Using Landsat and Corona Satellite Imagery for Tehran and the Alborz Mountains, Iran

    Directory of Open Access Journals (Sweden)

    Alexander Fekete

    2017-01-01

    Full Text Available Tehran, Karaj, Quazvin and nearby rural areas in the Alborz Mountains, Iran are prone to earthquake and landslide hazards. Risks for settlement areas, transport infrastructure and pastoralist areas exist due to a combination of natural as well as man-made factors. This study analyses data derived from satellite and airborne sensors, specifically, Landsat and declassified Corona data to identify landslide occurrence and urban sprawl. In a Geographic Information System, other data such as geology, topography, road network and river flows were integrated from various sources. A digital elevation model (DEM was computed based on contour lines that were extracted from topographic maps. The DEM allows for mapping topographic factors such as slope angle and aspect. Finally, change detection analysis has documented urban sprawl in massive dimensions since the 1970s. A multi-criteria landslide hazard and exposure zonation map was developed for a small rural area where several settlements and segments of roads were affected by landslides. The estimated risk areas were then overlaid with real landslide occurrences. The match of hypothetical and real event occurrence areas demonstrated the feasibility of this approach. The main contribution of this paper is to inform about recent landslide risks in Iran and how certain factors can be derived from spatial information.

  18. Landslide susceptibility modeling in a landslide prone area in Mazandarn Province, north of Iran: a comparison between GLM, GAM, MARS, and M-AHP methods

    Science.gov (United States)

    Pourghasemi, Hamid Reza; Rossi, Mauro

    2016-08-01

    Landslides are identified as one of the most important natural hazards in many areas throughout the world. The essential purpose of this study is to compare general linear model (GLM), general additive model (GAM), multivariate adaptive regression spline (MARS), and modified analytical hierarchy process (M-AHP) models and assessment of their performances for landslide susceptibility modeling in the west of Mazandaran Province, Iran. First, landslides were identified by interpreting aerial photographs, and extensive field works. In total, 153 landslides were identified in the study area. Among these, 105 landslides were randomly selected as training data (i.e. used in the models training) and the remaining 48 (30 %) cases were used for the validation (i.e. used in the models validation). Afterward, based on a deep literature review on 220 scientific papers (period between 2005 and 2012), eleven conditioning factors including lithology, land use, distance from rivers, distance from roads, distance from faults, slope angle, slope aspect, altitude, topographic wetness index (TWI), plan curvature, and profile curvature were selected. The Certainty Factor (CF) model was used for managing uncertainty in rule-based systems and evaluation of the correlation between the dependent (landslides) and independent variables. Finally, the landslide susceptibility zonation was produced using GLM, GAM, MARS, and M-AHP models. For evaluation of the models, the area under the curve (AUC) method was used and both success and prediction rate curves were calculated. The evaluation of models for GLM, GAM, and MARS showed 90.50, 88.90, and 82.10 % for training data and 77.52, 70.49, and 78.17 % for validation data, respectively. Furthermore, The AUC value of the produced landslide susceptibility map using M-AHP showed a training value of 77.82 % and validation value of 82.77 % accuracy. Based on the overall assessments, the proposed approaches showed reasonable results for landslide

  19. Hazard Assessment Comparison of Tazhiping Landslide Before and After Treatment

    OpenAIRE

    Huang, Dong; Qiao, Jianping; Wang, Meng

    2017-01-01

    Through investigation and analysis of geological conditions and mechanical parameters of the Taziping landslide, the finite volume method was adopted, and, the rheological model was adopted to simulate the landslide and avalanche entire mass movement process. The present paper adopted the GIS platform to simulate the mass movement process before and after treatment. This paper also provided the conditions and characteristic parameters of soil deposits (thickness, speed, and stresses) during t...

  20. Debris flow and landslide hazard mapping and risk analysis in China

    Institute of Scientific and Technical Information of China (English)

    Xilin LIU; Chengjun YU; Peijun SHI; Weihua FANG

    2012-01-01

    This paper assesses the hazardousness,vulnerability and risk of debris flow and landslide in China and compiles maps with a scale of 1∶6000000,based on Geographical Information System (GIS) technology,hazard regionalization map,socioeconomic data from 2000.Integrated hazardousness of debris flow and landslide is equivalent to the sum of debris flow hazardousness and landslide hazardousness.Vulnerability is assessed by employing a simplified assessment model.Risk is calculated by the following formula:Risk =Hazardousness × Vulnerability.The analysis results of assessment of hazardousness,vulnerability and risk show that there are extremely high risk regions of 104 km2,high risk regions of 283008 km2,moderate risk regions of 3161815 km2,low risk regions of 3299604km2,and extremely low risk regions of 2681709 km2.Exploitation activities should be prohibited in extremely high risk and high risk regions and restricted in moderate risk regions.The present study on risk analysis of debris flow and landslide not only sheds new light on the future work in this direction but also provides a scientific basis for disaster prevention and mitigation policy making.

  1. Flow-type failures in fine-grained soils: an important aspect in landslide hazard analysis

    Directory of Open Access Journals (Sweden)

    T. W. J. van Asch

    2009-10-01

    Full Text Available Forecasting the possibility of flow-type failures within a slow-moving landslide mass is rarely taken into account in quantitative hazard assessments. Therefore, this paper focuses on the potential transition of sliding blocks (slumps into flow-like processes due to the generation of excess pore water pressure in undrained conditions. The generation of excess pore water pressure may be the consequence of deformation of the landslide body during motion. Two model concepts are proposed and discussed. The first concept is the so called strain concept model where emphasis is laid on strain changes due to differential movement within the moving mass. This may create zones of compression and dilation and consequently excess pore water pressures. The second concept is the so called topographical concept model which focuses on changes in the stress field of the landslide caused by geometric changes in topography of the moving body. Both models were tested on two slumps which developed in secondary scarps of the Super-Sauze mudslide in the Barcelonnette Basin (South French Alps. The slump which developed in 1999 showed complete fluidization; all the material was removed from the source area and transformed into a mudflow. The second slump, dated from 2006, did not show fluidization; it has a relative short displacement and all the material remained in the source area. It appeared that the strain concept model predicted flow-type failure for both slumps, after relative short displacements, while the topographical concept model predicted only flow-type failure for the 1999 slump and not for the 2006 slump. The strain concept model seems too conservative in forecasting the fluidization potential of slumping blocks.

  2. Environmental resources of selected areas of Hawaii: Geological hazards

    Energy Technology Data Exchange (ETDEWEB)

    Staub, W.P.; Reed, R.M.

    1995-03-01

    This report has been prepared to make available and archive the background scientific data and related information collected on geologic hazards during the preparation of the environmental impact statement (EIS) for Phases 3 and 4 of the Hawaii Geothermal Project (HGP) as defined by the state of Hawaii in its April 1989 proposal to Congress. The US Department of Energy (DOE) published a notice withdrawing its Notice of Intent to prepare the HGP-EIS. Since the state of Hawaii is no longer pursuing or planning to pursue the HGP, DOE considers the project to be terminated. This report presents a review of current information on geologic hazards in the Hawaiian Islands. Interrelationships among these hazards are discussed. Probabilities of occurrence of given geologic hazards are provided in various regions where sufficient geologic or historical data are available. Most of the information contained herein is compiled from recent US Geological Survey (USGS) publications and USGS open-file reports related to this project. This report describes the natural geologic hazards present in the area and does not represent an assessment of environmental impacts. Geologic hazards originate both onshore and offshore. Onshore geologic hazards such as volcanic eruptions, earthquakes, surface rupture, landslides, uplift and subsidence occur mainly on the southern third of the island of Hawaii (hereinafter referred to as Hawaii). Offshore geologic hazards are more widely distributed throughout the Hawaiian Islands. Examples of offshore geologic hazards are submarine landslides, turbidity currents, and seismic sea waves (tsunamis).

  3. An offline-online Web-GIS Android application for fast data acquisition of landslide hazard and risk

    Science.gov (United States)

    Olyazadeh, Roya; Sudmeier-Rieux, Karen; Jaboyedoff, Michel; Derron, Marc-Henri; Devkota, Sanjaya

    2017-04-01

    Regional landslide assessments and mapping have been effectively pursued by research institutions, national and local governments, non-governmental organizations (NGOs), and different stakeholders for some time, and a wide range of methodologies and technologies have consequently been proposed. Land-use mapping and hazard event inventories are mostly created by remote-sensing data, subject to difficulties, such as accessibility and terrain, which need to be overcome. Likewise, landslide data acquisition for the field navigation can magnify the accuracy of databases and analysis. Open-source Web and mobile GIS tools can be used for improved ground-truthing of critical areas to improve the analysis of hazard patterns and triggering factors. This paper reviews the implementation and selected results of a secure mobile-map application called ROOMA (Rapid Offline-Online Mapping Application) for the rapid data collection of landslide hazard and risk. This prototype assists the quick creation of landslide inventory maps (LIMs) by collecting information on the type, feature, volume, date, and patterns of landslides using open-source Web-GIS technologies such as Leaflet maps, Cordova, GeoServer, PostgreSQL as the real DBMS (database management system), and PostGIS as its plug-in for spatial database management. This application comprises Leaflet maps coupled with satellite images as a base layer, drawing tools, geolocation (using GPS and the Internet), photo mapping, and event clustering. All the features and information are recorded into a GeoJSON text file in an offline version (Android) and subsequently uploaded to the online mode (using all browsers) with the availability of Internet. Finally, the events can be accessed and edited after approval by an administrator and then be visualized by the general public.

  4. A multi-objective decision-making method for the treatment scheme of landslide hazard

    Institute of Scientific and Technical Information of China (English)

    Quanmin Xie; Yuanyou Xia

    2004-01-01

    The treatment engineering of landslide hazard is a complicated system engineering. The selecting treatment scheme is influenced by many factors such as technology, economics, environment, and risk. The decision-making of treatment schemes of landslide hazard is a problem of comprehensive judgment with multi-hierarchy and multi-objective. The traditional analysis hierarchy process needs identity test. The traditional analysis hierarchy process is improved by means of optimal transfer matrix here. An improved hierarchy decision-making model for the treatment of landslide hazard is set up. The judgment matrix obtained by the method can naturally meet the requirement of identity, so the identity test is not necessary. At last, the method is applied to the treatment decision-making of the dangerous rock mass at the Slate Mountain, and its application is discussed in detail.

  5. Assessment, prevention and mitigation of landslide hazard in the Lesser Himalaya of Himachal Pradesh

    Directory of Open Access Journals (Sweden)

    Patra Punyatoya

    2015-09-01

    Full Text Available Landslides are destructive geological processes that have globally caused deaths and destruction to property worth billion dollars. Landslide occurrences are widespread and prolific in India covering more than 15 per cent of the total area. These are mostly concentrated in the Himalayan belt, parts of Meghalaya Plateau, Nilgiri Hills, Western and Eastern Ghats. The slope failure in the hilly terrain is due to geological processes and events. The frequency and magnitude of slope failure also increased due to anthropogenic activities such as road construction, deforestation and urban expansion. Keeping all these problems in mind research focuses on the Lesser Himalaya of Himachal Himalaya as it falls under very high risk zone in case of landslides and comprise of three objectives. They are: a to analyse the spatial pattern of landslides in the Lesser Himalaya, b to assess the causes of landslides vulnerability in the study region and c to suggests some preventive measures to mitigate landslides. In this work an attempt has been made to collect data on landslides incidences and damage from the secondary sources like Geological Survey of India, Building Material and Technology Promotion council from Ministry of Urban Affairs. The methodologies adopted for data analysis are simple tabulations, bar diagrams, statistical and mapping techniques to represent the Landslide vulnerability of the Lesser Himalaya. The analysis of the study reveals that there is increase in the number of landslides. The spatial pattern of landslide shows linear patterns, viz. along roads, rivers or lineaments/ faults. Besides, heavy rainfall, floods and earthquakes enhance the vulnerability condition. The landslides may be part and parcel of the Himalayan landscape, but they can be mitigated by some suitable measures. Few methods of landslide prevention in the study region have been suggested.

  6. DTMs Assessment to the Definition of Shallow Landslides Prone Areas

    Science.gov (United States)

    Martins, Tiago D.; Oka-Fiori, Chisato; Carvalho Vieira, Bianca; Montgomery, David R.

    2017-04-01

    Predictive methods have been developed, especially since the 1990s, to identify landslide prone areas. One of the examples it is the physically based model SHALSTAB (Shallow Landsliding Stability Model), that calculate the potential instability for shallow landslides based on topography and physical soil properties. Normally, in such applications in Brazil, the Digital Terrain Model (DTM), is obtained mainly from conventional contour lines. However, recently the LiDAR (Light Detection and Ranging) system has been largely used in Brazil. Thus, this study aimed to evaluate different DTM's, generated from conventional data and LiDAR, and their influence in generating susceptibility maps to shallow landslides using SHALSTAB model. For that were analyzed the physical properties of soil, the response of the model when applying conventional topographical data and LiDAR's in the generation of DTM, and the shallow landslides susceptibility maps based on different topographical data. The selected area is in the urban perimeter of the municipality of Antonina (PR), affected by widespread landslides in March 2011. Among the results, it was evaluated different LiDAR data interpolation, using GIS tools, wherein the Triangulation/Natural Neighbor presented the best performance. It was also found that in one of evaluation indexes (Scars Concentration), the LiDAR derived DTM presented the best performance when compared with the one originated from contour lines, however, the Landslide Potential index, has presented a small increase. Consequently, it was possible to assess the DTM's, and the one derived from LiDAR improved very little the certitude percentage. It is also noted a gap in researches carried out in Brazil on the use of products generated from LiDAR data on geomorphological analysis.

  7. Preliminary assessment of landslide-induced wave hazards, Tidal Inlet, Glacier Bay National Park, Alaska

    Science.gov (United States)

    Wieczorek, Gerald F.; Jakob, Matthias; Motyka, Roman J.; Zirnheld, Sandra L.; Craw, Patricia

    2003-01-01

    A large potential rock avalanche above the northern shore of Tidal Inlet, Glacier Bay National Park, Alaska, was investigated to determine hazards and risks of landslide-induced waves to cruise ships and other park visitors. Field and photographic examination revealed that the 5 to 10 million cubic meter landslide moved between AD 1892 and 1919 after the retreat of Little Ice Age glaciers from Tidal Inlet by AD 1890. The timing of landslide movement and the glacial history suggest that glacial debuttressing caused weakening of the slope and that the landslide could have been triggered by large earthquakes of 1899-1900 in Yakutat Bay. Evidence of recent movement includes fresh scarps, back-rotated blocks, and smaller secondary landslide movements. However, until there is evidence of current movement, the mass is classified as a dormant rock slump. An earthquake on the nearby active Fairweather fault system could reactivate the landslide and trigger a massive rock slump and debris avalanche into Tidal Inlet. Preliminary analyses show that waves induced by such a landslide could travel at speeds of 45 to 50 m/s and reach heights up to 76 m with wave runups of 200 m on the opposite shore of Tidal Inlet. Such waves would not only threaten vessels in Tidal Inlet, but would also travel into the western arm of Glacier Bay endangering large cruise ships and their passengers.

  8. A water balance approach to enhance national (GB) Daily Landslide Hazard Assessments

    Science.gov (United States)

    Dijkstra, Tom; Reeves, Helen; Freeborough, Katy; Dashwood, Claire; Pennington, Catherine; Jordan, Hannah; Hobbs, Peter; Richardson, Jennifer; Banks, Vanessa; Cole, Steven; Wells, Steven; Moore, Robert

    2017-04-01

    The British Geological Survey (BGS) is a member of the Natural Hazards Partnership (NHP) and delivers a national (GB) daily landslide hazard assessment (DLHA). The DLHA is based largely on 'expert' driven evaluations of the likelihood of landslides in response to antecedent ground conditions, adverse weather and reported landslide events. It concentrates on shallow translational slides and debris flows - events that most frequently have societal consequences by disrupting transport infrastructure and affecting buildings. Considerable experience with the issuing of DLHAs has been gained since 2012. However, it remains very difficult to appropriately assess changing ground conditions throughout GB even when good quality precipitation forecasts are available. Soil moisture sensors are available, but the network is sparse and not yet capable of covering GB to the detail required to underpin the forecasts. Therefore, we developed an approach where temporal and spatial variations in soil moisture can be obtained from a water balance model, representing processes in the near-surface and configured on a relatively coarse grid of 1 km2. Model outputs are not intended to be relevant to the slope scale. The assumption is that the likelihood of landslides being triggered by rainfall is dependent upon the soil moisture conditions of the near-surface, in combination with how much rain is forecast to occur for the following day. These variables form the basis for establishing thresholds to guide the issuing of DLHA and early warnings. The main aim is to obtain an insight into regional patterns of change and threshold exceedance. The BGS water balance model is still in its infancy and it requires substantial work to fine-tune and validate it. To test the performance of the BGS model we focused on an analysis of Scottish landslides (2004-2015) comprising translational slides and debris flows where the BGS model is conditionally evaluated against the Grid-to-Grid (G2G) Model. G2G is

  9. Analysing post-earthquake landslide activity using multi-temporal landslide inventories near the epicentral area of the 2008 Wenchuan earthquake

    Science.gov (United States)

    Tang, Chenxiao; Van Westen, Cees J.; Tanyas, Hakan; Jetten, Victor G.

    2016-12-01

    Large earthquakes in mountainous regions may trigger thousands of landslides, some active for years. We analysed the changes in landslide activity near the epicentre of the 2008 Wenchuan earthquake by generating five landslide inventories for different years through stereoscopic digital visual image interpretation. From May 2008 to April 2015, 660 new landslides occurred outside the co-seismic landslide areas. In April 2015, the number of active landslides had gone down to 66, less than 1 % of the co-seismic landslides, but still much higher than the pre-earthquake levels. We expect that the landslide activity will continue to decay, but may be halted if extreme rainfall events occur.

  10. An overview of a GIS method for mapping landslides and assessing landslide hazards at Río El Estado watershed, on the SW flank of Pico de Orizaba Volcano, Mexico

    Science.gov (United States)

    Legorreta Paulin, G.; Bursik, M. I.; Contreras, T.; Polenz, M.; Ramírez Herrera, M.; Paredes Mejía, L.; Arana Salinas, L.

    2012-12-01

    This poster provides an overview of the on-going research project (Grant SEP-CONACYT no 167495) from the Institute of Geography at the National Autonomous University of Mexico (UNAM) that seeks to conduct a multi-temporal landslide inventory, produce a landslide susceptibility map, and estimate sediment production by using Geographic Information Systems (GIS). The Río El Estado watershed on the southwestern flank of Pico de Orizaba volcano, the highest mountain in Mexico, is selected as a study area. The catchment covers 5.2 km2 with elevations ranging from 2676.79 to 4248.2 m a.s.l. and hillslopes between 0° and 56°. The stream system of Río El Estado catchment erodes Tertiary and Quaternary lavas, pyroclastic flows, and fall deposits. The geologic and geomorphologic factors in combination with high seasonal precipitation, high degree of weathering, and steep slopes predispose the study area to landslides. The methodology encompasses three main stages of analysis to assess landslide hazards: Stage 1 builds a historic landslide inventory. In the study area, an inventory of more than 170 landslides is created from multi-temporal aerial-photo-interpretation and local field surveys to assess landslide distribution. All landslides were digitized into a geographic information system (GIS), and a spatial geo-database of landslides was constructed from standardized GIS datasets. Stage 2 Calculates the susceptibility for the watershed. During this stage, Multiple Logistic Regression and SINMAP) will be evaluated to select the one that provides scientific accuracy, technical accessibility, and applicability. Stage 3 Estimate the potential total material delivered to the main stream drainage channel by all landslides in the catchment. Detailed geometric measurements of individual landslides visited during the field work will be carried out to obtain the landslide area and volume. These measurements revealed an empirical relationship between area and volume that took the

  11. Probabilistic Hazard of Tsunamis Generated by Submarine Landslides in the Cook Strait Canyon (New Zealand)

    Science.gov (United States)

    Lane, Emily M.; Mountjoy, Joshu J.; Power, William L.; Mueller, Christof

    2016-12-01

    Cook Strait Canyon is a submarine canyon that lies within ten kilometres of Wellington, the capital city of New Zealand. The canyon walls are covered with scars from previous landslides which could have caused local tsunamis. Palaeotsunami evidence also points to past tsunamis in the Wellington region. Furthermore, the canyon's location in Cook Strait means that there is inhabited land in the path of both forward- and backward-propagating waves. Tsunamis induced by these submarine landslides pose hazard to coastal communities and infrastructure but major events are very uncommon and the historical record is not extensive enough to quantify this hazard. The combination of infrequent but potentially very consequential events makes realistic assessment of the hazard challenging. However, information on both magnitude and frequency is very important for land use planning and civil defence purposes. We use a multidisciplinary approach bringing together geological information with modelling to construct a Probabilistic Tsunami Hazard Assessment of submarine landslide-generated tsunami. Although there are many simplifying assumptions used in this assessment, it suggests that the Cook Strait open coast is exposed to considerable hazard due to submarine landslide-generated tsunamis. We emphasise the uncertainties involved and present opportunities for future research.

  12. Web Application for Coastal Area Planning through Analysis of Landslide and Soil Consumption

    Science.gov (United States)

    Panizzoni, Giulio; Debiasi, Alberto; Eccher, Matteo; De Amicis, Raffaele

    2016-04-01

    Global warming and rapid climatic changes are producing dramatic effects on coastal area of Mediterranean countries. Italian coastal areas are one of the most urbanized zones of the south western Europe and the extensive use of soil is causing a consistent impact on the hydrogeological context. Moreover, soil consumption combined with extreme meteorological events, facilitates the occurrence of hazardous landslide events. Environmental policy makers and data managers in territorial planning need to face such emergency situation with appropriate tools. We present an application service with the aim of advising user through environmental analysis of Landslide and Soil Consumption impact. This service wants also to improve the sharing of environmental harmonized datasets/metadata across different organizations and the creation of a collaborative environment where the stakeholders and environmental experts can share their data and work cooperatively. We developed a set of processing services providing functionalities to assess impact of landslide on territory and impact of land take and soil sealing. Among others, the service is able to evaluate environmental impacts of landslide events on Cultural Heritage sites. We have also designed a 3D WebGL client customized to execute the processing services and visualize their outputs. It provides high usability in terms of navigation and data visualization. In this way the service provides not only a Spatial Data Infrastructure to access and visualize data but a complete Decision Support Systems for a more effective environmental planning of coastal area.

  13. Hydrologic impacts of landslide disturbances: Implications for remobilization and hazard persistence

    Science.gov (United States)

    Mirus, Benjamin B.; Smith, Joel B.; Baum, Rex L.

    2017-01-01

    Landslides typically alter hillslope topography, but may also change the hydrologic connectivity and subsurface water-storage dynamics. In settings where mobile materials are not completely evacuated from steep slopes, influences of landslide disturbances on hillslope hydrology and susceptibility to subsequent failures remain poorly characterized. Since landslides often recur at the site of previous failures, we examine differences between a stable vegetated hillslope (VH) and a recent landslide (LS). These neighboring hillslopes exhibit similar topography and are situated on steep landslide-prone coastal bluffs of glacial deposits along the northeastern shore of Puget Sound, Washington. Our control hillslope, VH, is mantled by a heterogeneous colluvium, supporting a dense forest. In early 2013, our test hillslope, LS, also supported a forest before a landslide substantially altered the topography and disturbed the hillslope. In 2015, we observed a clay-rich landslide deposit at LS with sparse vegetation and limited root reinforcement, soil structures, and macropores. Our characterization of the sites also found matrix porosity and hydraulic conductivity are both lower at LS. Continuous monitoring during 2015-2016 revealed reduced effective precipitation at VH (due to canopy interception), an earlier seasonal transition to near-saturated conditions at LS, and longer persistence of positive pore pressures and slower drainage at LS (both seasonally and between major storm events). These differences, along with episodic, complex slope failures at LS support the hypothesis that, despite a reduced average slope, other disturbances introduced by landsliding may promote the hydrologic conditions leading to slope instability, thus contributing to the persistence of landslide hazards.

  14. Landslide!

    Science.gov (United States)

    Hall-Wallace, Michelle; Mitchell, Carl

    1996-01-01

    Presents a unit that focuses on landslides and integrates earth science, physics, chemistry, and math. Includes activities to investigate porosity, permeability, cohesion, saturation, and gravity. (JRH)

  15. Landslide!

    Science.gov (United States)

    Hall-Wallace, Michelle; Mitchell, Carl

    1996-01-01

    Presents a unit that focuses on landslides and integrates earth science, physics, chemistry, and math. Includes activities to investigate porosity, permeability, cohesion, saturation, and gravity. (JRH)

  16. A model for assessing the systemic vulnerability in landslide prone areas

    Directory of Open Access Journals (Sweden)

    S. Pascale

    2010-07-01

    Full Text Available The objectives of spatial planning should include the definition and assessment of possible mitigation strategies regarding the effects of natural hazards on the surrounding territory. Unfortunately, however, there is often a lack of adequate tools to provide necessary support to the local bodies responsible for land management. This paper deals with the conception, the development and the validation of an integrated numerical model for assessing systemic vulnerability in complex and urbanized landslide-prone areas. The proposed model considers this vulnerability not as a characteristic of a particular element at risk, but as a peculiarity of a complex territorial system, in which the elements are reciprocally linked in a functional way. It is an index of the tendency of a given territorial element to suffer damage (usually of a functional kind due to its interconnections with other elements of the same territorial system. The innovative nature of this work also lies in the formalization of a procedure based on a network of influences for an adequate assessment of such "systemic" vulnerability.

    This approach can be used to obtain information which is useful, in any given situation of a territory hit by a landslide event, for the identification of the element which has suffered the most functional damage, ie the most "critical" element and the element which has the greatest repercussions on other elements of the system and thus a "decisive" role in the management of the emergency.

    This model was developed within a GIS system through the following phases:

    1. the topological characterization of the territorial system studied and the assessment of the scenarios in terms of spatial landslide hazard. A statistical method, based on neural networks was proposed for the assessment of landslide hazard;

    2. the analysis of the direct consequences of a scenario event on the system;

    3. the definition of the

  17. A model for assessing the systemic vulnerability in landslide prone areas

    Science.gov (United States)

    Pascale, S.; Sdao, F.; Sole, A.

    2010-07-01

    The objectives of spatial planning should include the definition and assessment of possible mitigation strategies regarding the effects of natural hazards on the surrounding territory. Unfortunately, however, there is often a lack of adequate tools to provide necessary support to the local bodies responsible for land management. This paper deals with the conception, the development and the validation of an integrated numerical model for assessing systemic vulnerability in complex and urbanized landslide-prone areas. The proposed model considers this vulnerability not as a characteristic of a particular element at risk, but as a peculiarity of a complex territorial system, in which the elements are reciprocally linked in a functional way. It is an index of the tendency of a given territorial element to suffer damage (usually of a functional kind) due to its interconnections with other elements of the same territorial system. The innovative nature of this work also lies in the formalization of a procedure based on a network of influences for an adequate assessment of such "systemic" vulnerability. This approach can be used to obtain information which is useful, in any given situation of a territory hit by a landslide event, for the identification of the element which has suffered the most functional damage, ie the most "critical" element and the element which has the greatest repercussions on other elements of the system and thus a "decisive" role in the management of the emergency. This model was developed within a GIS system through the following phases: 1. the topological characterization of the territorial system studied and the assessment of the scenarios in terms of spatial landslide hazard. A statistical method, based on neural networks was proposed for the assessment of landslide hazard; 2. the analysis of the direct consequences of a scenario event on the system; 3. the definition of the assessment model of systemic vulnerability in landslide-prone areas. To

  18. GIS-based landslide hazard evaluation at the regional scale: some critical points in the permanent displacement approach for seismically-induced landslide maps

    Science.gov (United States)

    Vessia, Giovanna; Parise, Mario

    2013-04-01

    the assumed depth of the sliding surface. Thus, it is of paramount relevance to correctly understand and describe the dynamic behavior of the lithologies affected by the earthquake. Accordingly, we put here in evidence some critical points in the application of the permanent displacement formulations by considering the case study of Santa Susana Mountains (California, USA) shaken by the Northridge earthquake in 1994. During this earthquake, a high number of registrations has been collected, whilst soon after a careful inventory of the mass movements triggered by the shaking has been produced, together with analysis of the related failure mechanisms. Hence, these data allow to perform a back analysis in order to verify the reliability of some numerical expressions, such as those proposed by Ambraseys and Menu (1988), Romeo (2000), and Jibson (2007), with respect to the possible dynamic behavior of the lithologies affected by landslides. In this sector of California, the following lithologies crop out, that were involved in shallow landslides: (1) Quaternay deposits; (2) Saugus Formation; (3) Towsley Formation; (4) Pico Formation; (5) Topanga Formation; (6) Modelo Formation; (7) Simi Conglomerate; (8) Santa Susana Formation; (9) Llajas and Chatsworth Formations. The surveys carried out after the Northridge earthquake (Harp and Jibson, 1995), and the analysis of landslide distribution (Parise and Jibson 2000) pointed out that the strongest formations with slopes higher than 50° mainly suffered toppling or fall failures: thus, our hazard maps based on permanent displacements did not take into account such range of slopes. Further, areas with slopes lower than 10° were not affected by relevant mass movements. Thus, a limited range of slopes (between 10° and 45°) was considered in the analyses, with depth of the sliding surface varying between 1 and 3 m, and using the resistance parameters of involved lithologies obtained from in situ and laboratory tests performed by

  19. Hunza Landslide and Monsoon Flooding in Pakistan Call for International Attention to Transboundary Natural Hazards

    Science.gov (United States)

    Kargel, J. S.; Fink, W.; Furfaro, R.; Leonard, G. J.; Patterson, M.; Glims, Gaphaz

    2010-12-01

    Two major disasters in Pakistan and innumerable lesser disasters throughout the Himalaya-Karakoram region in 2010 highlight geologic events and extreme weather (perhaps climate change) in affecting the well being of whole nations and commerce and relations between nations. Two chief events in Pakistan include the Jan. 4 rockslide into the Hunza River and the subsequent formation of a natural dam lake (Lake Gojal); and the monsoon precipitation-fed flooding across the Indus Basin. The first event severed Pakistan’s major land link with China. The second event devastated Pakistan’s national land-based transportation infrastructure and agriculture and displaced millions of people. In a country plagued by monsoon-driven floods, the lack of catastrophic breakout of Lake Gojal is welcome. Satellite-based monitoring shows the spillway to be eroding more rapidly (but not alarmingly) under August’s monsoon peak flow. Similar events have occurred before in the region and will occur again. These mega-events in Pakistan should be an alert for all of South Asia, as climate change increases or shifts the hazard environment, encroaching development and urbanization increases the vulnerabilities, and as improved capacity for trans-national commerce breaks down the Himalayan barrier and both promotes new opportunities and possible conflicts. 2010's natural mega-calamities in Pakistan and widespread landsliding and flooding elsewhere in South Asia underscores the subcontinent’s need for a thorough field-, remote sensing-, and modeling-based assessment of the disaster potential related to landslides, glacier surges, extreme monsoon precipitation events, natural glacier and landslide dam lake outbursts, and unseasonal snow melting. The Himalayan-Karakoram region is remarkable for its heterogeneous responses to climate change. For instance, some areas are undergoing rapid glacier recession and stagnation; others are undergoing glacier growth. We take the instance of the

  20. A Monitoring Network to Map and Assess Landslide Activity in a Highly Anthropized Area

    Directory of Open Access Journals (Sweden)

    Giulia Bossi

    2016-09-01

    Full Text Available Mapping landslide activity in a highly anthropized area entails specific problems. The integration of different monitoring techniques in order to measure the displacements rate within the slope is mandatory. We describe our activity for the Mortisa landslide which is located on the western flank of the Cortina d’Ampezzo valley (northeastern Italy in a highly anthropized area in the heart of the Dolomites, a UNESCO world heritage site. The mass movement threatens some houses, an important national road, and part of the area that will be the venue for the upcoming 2021 Alpine Skiing World Championship. The hazardous context along with its prestigious location makes the construction of new settlements and infrastructure very challenging. Owing to that, precise mapping and assessment of the activity of the Mortisa landslide is extremely important. To achieve this task, multitemporal aerial photo interpretation, A-DInSAR analysis, Global Navigation Satellite System (GNSS surveys, and inclinometric measurements were performed. Through the integration of the monitoring data and geomorphological interpretation, a hazard map of the Mortisa area was produced with the intent to assist the local authorities in the definition of the new urban development plan.

  1. Validating national landslide susceptibility and hazard maps for Caribbean island countries: the case of Dominica and tropical storm Erika.

    Science.gov (United States)

    van Westen, Cees; Jetten, Victor; Alkema, Dinand

    2016-04-01

    The aim of this study was to generate national-scale landslide susceptibility and hazard maps for four Caribbean islands, as part of the World Bank project CHARIM (Caribbean Handbook on Disaster Geoinformation Management, www.charim.net). This paper focuses on the results for the island country of Dominica, located in the Eastern part of the Caribbean, in-between Guadalupe and Martinique. The available data turned out to be insufficient to generate reliable results. We therefore generated a new database of disaster events for Dominica using all available data, making use of many different sources. We compiled landslide inventories for five recent rainfall events from the maintenance records of the Ministry of Public Works, and generated a completely new landslide inventory using multi-temporal visual image interpretation, and generated an extensive landslide database for Dominica. We analyzed the triggering conditions for landslides as far as was possible given the available data, and generated rainfall magnitude-frequency relations. We applied a method for landslide susceptibility assessment which combined bi-variate statistical analysis, that provided indications on the importance of the possible contributing factors, with an expert-based iterative weighing approach using Spatial Multi-Criteria Evaluation. The method is transparent, as the stakeholders (e.g. the engineers and planners from the four countries) and other consultants can consult the criteria trees and evaluate the standardization and weights, and make adjustments. The landslide susceptibility map was converted into a landslide hazard map using landslide density and frequencies for so called major, moderate and minor triggering events. The landslide hazard map was produced in May 2015. A major rainfall event occurred on Dominica following the passage of tropical storm Erika on 26 to 28 August 2015. An event-based landslide inventory for this event was produced by UNOSAT using very high resolution

  2. Optical and Radar Satellite Remote Sensing for Large Area Analysis of Landslide Activity in Southern Kyrgyzstan, Central Asia

    Science.gov (United States)

    Roessner, S.; Behling, R.; Teshebaeva, K. O.; Motagh, M.; Wetzel, H. U.

    2014-12-01

    The presented work has been investigating the potential of optical and radar satellite remote sensing for the spatio-temporal analysis of landslide activity at a regional scale along the eastern rim of the Fergana Basin representing the area of highest landslide activity in Kyrgyzstan. For this purpose a multi-temporal satellite remote sensing database has been established for a 12.000 km2 study area in Southern Kyrgyzstan containing a multitude of optical data acquired during the last 28 years as well as TerraSAR-X and ALOS-PALSAR acquired since 2007. The optical data have been mainly used for creating a multi-temporal inventory of backdated landslide activity. For this purpose an automated approach for object-oriented multi-temporal landslide detection has been developed which is based on the analysis of temporal NDVI-trajectories complemented by relief information to separate landslide-related surface changes from other land cover changes. Applying the approach to the whole study area using temporal high resolution RapidEye time series data has resulted in the automated detection of 612 landslide objects covering a total area of approx. 7.3 km². Currently, the approach is extended to the whole multi-sensor time-series database for systematic analysis of longer-term landslide occurrence at a regional scale. Radar remote sensing has been focussing on SAR Interferometry (InSAR) to detect landslide related surface deformation. InSAR data were processed by repeat-pass interferometry using the DORIS and SARScape software. To better assess ground deformation related to individual landslide objects, InSAR time-series analysis has been applied using the Small Baseline Subset (SBAS) method. Analysis of the results in combination with optical data and DEM information has revealed that most of the derived deformations are caused by slow movements in areas of already existing landslides indicating the reactivation of older slope failures. This way, InSAR analysis can

  3. Submarine landslide and tsunami hazards offshore southern Alaska: Seismic strengthening versus rapid sedimentation

    Science.gov (United States)

    Sawyer, Derek E.; Reece, Robert S.; Gulick, Sean P. S.; Lenz, Brandi L.

    2017-08-01

    The southern Alaskan offshore margin is prone to submarine landslides and tsunami hazards due to seismically active plate boundaries and extreme sedimentation rates from glacially enhanced mountain erosion. We examine the submarine landslide potential with new shear strength measurements acquired by Integrated Ocean Drilling Program Expedition 341 on the continental slope and Surveyor Fan. These data reveal lower than expected sediment strength. Contrary to other active margins where seismic strengthening enhances slope stability, the high-sedimentation margin offshore southern Alaska behaves like a passive margin from a shear strength perspective. We interpret that seismic strengthening occurs but is offset by high sedimentation rates and overpressure. This conclusion is supported by shear strength outside of the fan that follow an active margin trend. More broadly, seismically active margins with wet-based glaciers are susceptible to submarine landslide hazards because of the combination of high sedimentation rates and earthquake shaking.

  4. Techniques, advances, problems and issues in numerical modelling of landslide hazard

    CERN Document Server

    Van Asch, Theo; Van Beek, Ludovicus; Amitrano, David

    2007-01-01

    Slope movements (e.g. landslides) are dynamic systems that are complex in time and space and closely linked to both inherited and current preparatory and triggering controls. It is not yet possible to assess in all cases conditions for failure, reactivation and rapid surges and successfully simulate their transient and multi-dimensional behaviour and development, although considerable progress has been made in isolating many of the key variables and elementary mechanisms and to include them in physically-based models for landslide hazard assessments. Therefore, the objective of this paper is to review the state-of-the-art in the understanding of landslide processes and to identify some pressing challenges for the development of our modelling capabilities in the forthcoming years for hazard assessment. This paper focuses on the special nature of slope movements and the difficulties related to simulating their complex time-dependent behaviour in mathematical, physically-based models. It analyses successively th...

  5. Multi-Hazard Analysis for the Estimation of Ground Motion Induced by Landslides and Tectonics

    Science.gov (United States)

    Iglesias, Rubén; Koudogbo, Fifame; Ardizzone, Francesca; Mondini, Alessandro; Bignami, Christian

    2016-04-01

    Space-borne synthetic aperture radar (SAR) sensors allow obtaining all-day all-weather terrain complex reflectivity images which can be processed by means of Persistent Scatterer Interferometry (PSI) for the monitoring of displacement episodes with extremely high accuracy. In the work presented, different PSI strategies to measure ground surface displacements for multi-scale multi-hazard mapping are proposed in the context of landslides and tectonic applications. This work is developed in the framework of ESA General Studies Programme (GSP). The present project, called Multi Scale and Multi Hazard Mapping Space based Solutions (MEMpHIS), investigates new Earth Observation (EO) methods and new Information and Communications Technology (ICT) solutions to improve the understanding and management of disasters, with special focus on Disaster Risk Reduction rather than Rapid Mapping. In this paper, the results of the investigation on the key processing steps for measuring large-scale ground surface displacements (like the ones originated by plate tectonics or active faults) as well as local displacements at high resolution (like the ones related with active slopes) will be presented. The core of the proposed approaches is based on the Stable Point Network (SPN) algorithm, which is the advanced PSI processing chain developed by ALTAMIRA INFORMATION. Regarding tectonic applications, the accurate displacement estimation over large-scale areas characterized by low magnitude motion gradients (3-5 mm/year), such as the ones induced by inter-seismic or Earth tidal effects, still remains an open issue. In this context, a low-resolution approach based in the integration of differential phase increments of velocity and topographic error (obtained through the fitting of a linear model adjustment function to data) will be evaluated. Data from the default mode of Sentinel-1, the Interferometric Wide Swath Mode, will be considered for this application. Regarding landslides

  6. Application of indicators derived by remote sensing for mapping of landslide hazard and vulnerability

    Science.gov (United States)

    Eidsvig, Unni; Vidar Vangelsten, Bjørn; Geiss, Christian; Klotz, Martin; Ekseth, Kristine; Taubenböck, Hannes

    2014-05-01

    The choice and the development of methods for risk assessment of landslides depends on several factors. Important factors are the type of landslide and the elements at risk, the choice of spatial and temporal scale, the purpose of the analysis and the needs of the end-users. In addition, data availability is a major constraint, which greatly affects the type of methods and models that can be developed. Remote sensing is a promising tool for an economical and up-to-date data collection, which also could be applied to monitor the dynamic development of risk. The spatial and temporal distribution of the risk for landslides can be assessed by monitoring hazard indicators (e.g. slope height and slope angle), exposure indicators (e.g. number of houses and the total population) and vulnerability indicators (e.g. population density, settlement structures or indicators related to structural vulnerability). Several of the indicators applicable for landslide risk and vulnerability can be obtained by remote sensing techniques. However, for better results, indicators from remote sensing should be combined with other type of data. In this work, a review on the application of indicators for landslide risk assessment in explicit models as well as an assessment of end user needs was conducted in order to determine the most relevant indicators for landslide hazard and vulnerability. Lists of recommended indicators, mainly derivable from remote sensing, have been developed. These indicators are supposed to be used in risk assessment, e.g. by combining hazard, vulnerability and exposure indicators to produce risk indices. Moreover schemes for ranking, weighting and aggregation of the indicators into hazard- and vulnerability indices are provided. The research leading to these results has received funding from the European Community's Seventh Framework Programme [FP7-SPACE-2012-1] under Grant agreement No 312972 Framework to integrate Space-based and in-situ sENSing for dynamic v

  7. Landslides: Geomorphology and Sea Cliff Hazard Potential, Santa Barbara - Isla Vista, California J.F. Klath and E.A. Keller

    Science.gov (United States)

    Klath, J. F.; Keller, E. A.

    2015-12-01

    Coastal areas are often characterized by high population densities in an ever changing, dynamic environment. The world's coasts are often dominated by steeply sloping sea cliffs, the morphology of which reflects rock type, wave erosion, and surface erosion, as well as human activities such changing vegetation, urban runoff, and construction of coastal defenses. The Santa Barbara and Goleta area, with over 17 km of sea cliffs and beaches, extends from Santa Barbara Point west to the hamlet of Isla Vista. A deeper understanding of the local geology and the physical processes generating slope failure and, thus, landward cliff retreat is important for general public safety, as well as future development and planning. Our research objective includes assessment of landslide hazard potential through investigation of previous landslides and how these events relate to various physical variables and characteristics within the surrounding bedrock. How does landslide frequency, volume, and type relate to varying local bedrock and structure? Two geologic formations dominate the sea cliffs of the Santa Barbara area: Monterey shale (upper, middle, and lower) and Monterey Sisquoc shale. Geology varies from hard cemented shale and diatomaceous, low specific gravity shale to compaction shale. Variations in landslide characteristics are linked closely to the geology of a specific site that affects how easily rock units are weathered and eroded by wave erosion, naturally occurring oil and water seeps, burnt shale events, and landslide type and frequency on steeply dipped bedding planes/daylighting beds. Naturally occurring features linked to human processes often weaken bedrock and, thus, increase the likelihood of landslides. We categorize landslide frequency, type, and triggers; location of beach access, drainage pipes, and water; and oil and tar seeps in order to develop suggestions to minimize landslide potential. Lastly, using previously published erosion cliff retreat rates and

  8. Landslide hazard mapping by multivariate statistics: comparison of methods and case study in the Spanish Pyrenees

    NARCIS (Netherlands)

    Beguería, S.; Lorente, A.

    2007-01-01

    This paper, written as a deliverable of the DAMOCLES project, is a review of the different existing methodologies to landslide hazard mapping by multivariate statistics. Within the DAMOCLES project, multivariate statistical models have been applied to different study regions in Italy and Spain. The

  9. Environmental Resources of Selected Areas of Hawaii: Geological Hazards (DRAFT)

    Energy Technology Data Exchange (ETDEWEB)

    Staub, W.P.

    1994-06-01

    This report has been prepared to make available and archive the background scientific data and related information collected on geologic hazards during the preparation of the environmental impact statement (EIS) for Phases 3 and 4 of the Hawaii Geothermal Project (HGP) as defined by the state of Hawaii in its April 1989 proposal to Congress. The U.S. Department of Energy (DOE) published a notice in the Federal Register on May 17, 1994 (Fed Regis. 5925638) withdrawing its Notice of Intent (Fed Regis. 575433) of February 14, 1992, to prepare the HGP-EIS. Since the state of Hawaii is no longer pursuing or planning to pursue the HGP, DOE considers the project to be terminated This report presents a review of current information on geologic hazards in the Hawaiian Islands. Interrelationships among these hazards are discussed. Probabilities of occurrence of given geologic hazards are provided in various regions where sufficient geologic or historical data are available. Most of the information contained herein is compiled from recent U.S. Geological Survey (USGS) publications and open-file reports. This report describes the natural geologic hazards present in the area and does not represent an assessment of environmental impacts. Geologic hazards originate both onshore and offshore. Onshore geologic hazards such as volcanic eruptions, earthquakes, surface rupture, landslides, uplift, and subsidence occur mainly on the southern third of the island of Hawaii (hereinafter referred to as Hawaii). Offshore geologic hazards are more widely distributed throughout the Hawaiian Islands. Examples of offshore geologic hazards are submarine landslides, turbidity currents, and seismic sea waves (tsunamis). First, overviews of volcanic and earthquake activity, and details of offshore geologic hazards is provided for the Hawaiian Islands. Then, a more detailed discussion of onshore geologic hazards is presented with special emphasis on the southern third of Hawaii and the east rift

  10. Landslide Mobility and Hazards: A Geophysical Overview of the Oso Disaster

    Science.gov (United States)

    Iverson, R. M.; George, D. L.; Allstadt, K.; Godt, J.; Reid, M. E.; Vallance, J. W.; Schilling, S. P.; Cannon, C.; Magirl, C. S.; Collins, B. D.; Baum, R. L.; Coe, J. A.; Schulz, W. H.; Bower, J. B.

    2014-12-01

    much like that observed at Oso, and in a case with n = 0.36, it predicts much slower landsliding that ceases after only about 100 m of motion. This behavioral bifurcation has fundamental physical importance as well as large ramifications for assessment of landslide hazards.

  11. Hazard, Vulnerability and Capacity Mapping for Landslides Risk Analysis using Geographic Information System (GIS)

    Science.gov (United States)

    Sari, D. A. P.; Innaqa, S.; Safrilah

    2017-06-01

    This research analyzed the levels of disaster risk in the Citeureup sub-District, Bogor Regency, West Java, based on its potential hazard, vulnerability and capacity, using map to represent the results, then Miles and Huberman analytical techniques was used to analyze the qualitative interviews. The analysis conducted in this study is based on the concept of disaster risk by Wisner. The result shows that the Citeureup sub-District has medium-low risk of landslides. Of the 14 villages, three villages have a moderate risk level, namely Hambalang, Tajur, and Tangkil, or 49.58% of the total land area. Eleven villages have a low level of risk, namely Pasir Mukti, Sanja, Tarikolot, Gunung Sari, Puspasari, East Karang Asem, Citeureup, Leuwinutug, Sukahati, West Karang Asem West and Puspanegara, or 48.68% of the total land area, for high-risk areas only around 1.74%, which is part of Hambalang village. The analysis using Geographic Information System (GIS) prove that areas with a high risk potential does not necessarily have a high level of risk. The capacity of the community plays an important role to minimize the risk of a region. Disaster risk reduction strategy is done by creating a safe condition, which intensified the movement of disaster risk reduction.

  12. Landslide susceptibility from mathematical model in Sarno area

    Directory of Open Access Journals (Sweden)

    G. Capparelli

    2013-10-01

    Full Text Available Rainfall is accepted as a major precursor for many types of slope movements (rapid, shallow soil slips and deeper landslides and the technical literature is rich in examples of study cases and analysis models, related to landslides induced by rainfall. In general, the developed model can be regrouped in two categories: hydrological and complete. The first ones involve simple empirical relationships linking antecedent precipitation to the time that the landslide occurs; the latter consist of more complex expressions that take several components into account, including specific site conditions, mechanical, hydraulic and physical soil properties, local seepage conditions, and the contribution of these to soil strength. In this study, the analysis was carried out by using a model belonging to the second category for a landslide-prone area in Campania region (Southern Italy, were disastrous mud-flows occurred on 5 May 1998. In details, the model named SUSHI (Saturated Unsaturated Simulation for Hillslope Instability was used and the obtained results made possible to better define the triggering conditions and differentiate the scenarios leading to instability of those slopes.

  13. Analysis of the relationship between landslides size distribution and earthquake source area

    Science.gov (United States)

    Valagussa, Andrea; Crosta, Giovanni B.; Frattini, Paolo; Xu, Chong

    2014-05-01

    The spatial distribution of earthquake induced landslides around the seismogenetic source has been analysed to better understand the triggering of landslides in seismic areas and to forecast the maximum distance at which an earthquake, with a certain magnitude, can induce landslides (e.g Keefer, 1984). However, when applying such approaches to old earthquakes (e.g 1929 Buller and 1968 Iningahua earthquakes New Zealand; Parker, 2013; 1976 Friuli earthquake, Italy) one should be concerned about the undersampling of smaller landslides which can be cancelled by erosion and landscape evolution. For this reason, it is important to characterize carefully the relationship between landslide area and number with distance from the source, but also the size distribution of landslides as a function of distance from the source. In this paper, we analyse the 2008 Wenchuan earthquake landslide inventory (Xu et al, 2013). The earthquake triggered more than 197,000 landslides of different type, including rock avalanches, rockfalls, translational and rotational slides, lateral spreads and derbies flows. First, we calculated the landslide intensity (number of landslides per unit area) and spatial density (landslide area per unit area) as a function of distance from the source area of the earthquake. Then, we developed magnitude frequency curves (MFC) for different distances from the source area. Comparing these curves, we can describe the relation between the distance and the frequency density of landslide in seismic area. Keefer D K (1984) Landslides caused by earthquakes. Geological Society of America Bulletin, 95(4), 406-421. Parker R N, (2013) Hillslope memory and spatial and temporal distributions of earthquake-induced landslides, Durham theses, Durham University. Xu, C., Xu, X., Yao, X., & Dai, F. (2013). Three (nearly) complete inventories of landslides triggered by the May 12, 2008 Wenchuan Mw 7.9 earthquake of China and their spatial distribution statistical analysis

  14. Landslide prediction using combined deterministic and probabilistic methods in hilly area of Mt. Medvednica in Zagreb City, Croatia

    Science.gov (United States)

    Wang, Chunxiang; Watanabe, Naoki; Marui, Hideaki

    2013-04-01

    The hilly slopes of Mt. Medvednica are stretched in the northwestern part of Zagreb City, Croatia, and extend to approximately 180km2. In this area, landslides, e.g. Kostanjek landslide and Črešnjevec landslide, have brought damage to many houses, roads, farmlands, grassland and etc. Therefore, it is necessary to predict the potential landslides and to enhance landslide inventory for hazard mitigation and security management of local society in this area. We combined deterministic method and probabilistic method to assess potential landslides including their locations, size and sliding surfaces. Firstly, this study area is divided into several slope units that have similar topographic and geological characteristics using the hydrology analysis tool in ArcGIS. Then, a GIS-based modified three-dimensional Hovland's method for slope stability analysis system is developed to identify the sliding surface and corresponding three-dimensional safety factor for each slope unit. Each sliding surface is assumed to be the lower part of each ellipsoid. The direction of inclination of the ellipsoid is considered to be the same as the main dip direction of the slope unit. The center point of the ellipsoid is randomly set to the center point of a grid cell in the slope unit. The minimum three-dimensional safety factor and corresponding critical sliding surface are also obtained for each slope unit. Thirdly, since a single value of safety factor is insufficient to evaluate the slope stability of a slope unit, the ratio of the number of calculation cases in which the three-dimensional safety factor values less than 1.0 to the total number of trial calculation is defined as the failure probability of the slope unit. If the failure probability is more than 80%, the slope unit is distinguished as 'unstable' from other slope units and the landslide hazard can be mapped for the whole study area.

  15. GIS COMPONENT BASED 3D LANDSLIDE HAZARD ASSESSMENT SYSTEM: 3DSLOPEGIS

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In this paper, based on a new Geographic Information System (GIS) grid-based three-dimensional (3D) deterministic model and taken the slope unit as the study object, the landslide hazard is mapped by the index of the 3D safety factor. Compared with the one-dimensional (1D) model of infinite slope, which is now widely used for deterministic model based landslide hazard assessment in GIS, the GIS grid-based 3D model is more acceptable and is more adaptable for three-dimensional landslide. Assuming the initial slip as the lower part of an ellipsoid, the 3D critical slip surface in the 3D slope stability analysis is obtained by means of a minimization of the 3D safety factor using the Monte Carlo random simulation. Using a hydraulic model tool for the watershed analysis in GIS, an automatic process has been developed for identifying the slope unit from digital elevation model (DEM) data. Compared with the grid-based landslide hazard mapping method, the slope unit possesses clear topographical meaning, so its results are more credible. All the calculations are implemented by a computational program, 3DSlopeGIS, in which a GIS component is used for fulfilling the GIS spatial analysis function, and all the data for the 3D slope safety factor calculation are in the form of GIS data (the vector and the grid layers). Because of all these merits of the GIS-based 3D landslide hazard mapping method, the complex algorithms and iteration procedures of the 3D problem can also be perfectly implemented.

  16. Landslide Monitoring in Three Gorges Area by Joint Use of Phase Based and Amplitude Based Methods

    Science.gov (United States)

    Shi, Xuguo; Zhang, Lu; Liao, Mingsheng; Balz, Timo

    2015-05-01

    Landslides are serious geohazards in Three Gorges area, China especially after the impoundment of Three Gorges Reservoir. It is very urgent to monitoring the landslides for early warning or disaster prevention purpose. In this paper, phase based methods such as traditional differential InSAR and small baseline subset method were used to investigate slow moving landslides. Point-like targets offset tracking (PTOT) was used to investigate fast moving landslides. Furthermore, in order to describe the displacement on landslide, two TerraSAR-X datasets obtained from different descending orbits were combined to obtain the three dimensional displacements on Shuping landslides with the PTOT measurements in the azimuth and range direction.

  17. Evaluation of Tsunami Hazards in Kuwait from Possible Earthquake and Landslide Sources considering Effect of Natural Tide

    Science.gov (United States)

    Latcharote, P.

    2016-12-01

    Kuwait is one of the most important oil producers to the world and most of population and many vital facilities are located along the coasts. However, even with low or unknown tsunami risk, it is important to investigate tsunami hazards in this country to ensure safety of life and sustain the global economy. This study aimed to evaluate tsunami hazards along the coastal areas of Kuwait from both earthquake and landslide sources using numerical modeling. Tsunami generation and propagation was simulated using the two-layer model and the TUNAMI model. Four cases of earthquake scenarios are expected to generate tsunami along the Makran Subduction Zone (MSZ) based on historical events and worst cases possible to simulate tsunami propagation to the coastal areas of the Arabian Gulf. Case 1 (Mw 8.3) and Case 2 (Mw 8.3) are the replication of the 1945 Makran earthquake, whereas Case 3 (Mw 8.6) and Case 4 (Mw 9.0) are the worst-case scenarios. Tsunami numerical simulation was modelled with mesh size 30 arc-second using bathymetry and topography data from GEBCO. Preliminary results suggested that tsunamis generated by Case 1 and Case 2 will impose very small effects to Kuwait (coastal landslides were assumed occurred at the volume of 1.0-2.0 km3 at three possible locations from their topographic features. The preliminary results revealed that tsunami generated by coastal landslides could impose a significant tsunami impact to Kuwait having maximum tsunami amplitude at the Falika Island in front of Kuwait bay and Azzour power and desalination plant about 0.5 m- 1.1 m depending on landslide volume and energy dissipation. Future works will include more accuracy of tsunami numerical simulation with higher resolution of bathymetry and topography data in order to investigate tsunami inundation. Furthermore, detailed analysis on possible landslide sources will be performed by means of 3D-slope stability analysis in order to know the exact locations and landslide volumes taking into

  18. Landslide Monitoring with ALOS/PALSAR data in Mountain Area

    Science.gov (United States)

    Tian, X.; Qi, H.; Yu, B.

    2015-12-01

    InSAR is a relatively new technique with a high potential in earth observation, which has made great success in monitoring urban areas deformation. At present, although there are a considerable number of applications in the complicated mountain areas, it is hard to obtain sufficiently high-density stable point targets in these regions. So scientists have been trying to solve this bottleneck problem and improve accuracy in mountain areas. In this work, we present the landslide measurement result in complicated topographic region using ALOS/PALSAR data. The test area is selected around highlands of the boundary between China and India. We choose 13 scenes of ALOS/PALSAR images from May 2007 to February 2011. The main landforms in this experimental region are bare rock and soil, ice and snow, the vegetation in the alpine area. Due to the lithology of the strata and the undulations extent of the terrain, it is prone to cause landslides in the event of rainfall, earthquakes, snow melt or human activities. The traditional PS algorithm has a higher requirement for a long time series data collection, especially in low-coherence area of vegetation cover. As the collected data and stable points are relatively less in this experimental area, we plan to study the time series InSAR analysis coherence model and error model, and extend its application to the extra-urban regions. The approach has been carried out to increase the density of stable points, which are mainly distributed on the top of mountain and ridge areas. And using the 13 images we find several subsidence areas by this technique. The result shows that the top of mountain is relatively stable and the suspected landslide areas are mainly along the ridge, which is in accordance with the actual situation. Then the mechanism and stability analysis of landslide is discussed. Meanwhile, some other measurement data in experimental area is available for cross validation, such as optical data and TerraSAR-X data. And a

  19. Non-Susceptible Landslide Areas in Italy and in the Mediterranean Region

    Science.gov (United States)

    Alvioli, Massimiliano; Ardizzone, Francesca; Guzzetti, Fausto; Marchesini, Ivan; Rossi, Mauro

    2014-05-01

    Landslide susceptibility is the likelihood of a landslide occurring in a given area. Over the past three decades, researchers, and planning and environmental organisations have worked to assess landslide susceptibility at different geographical scales, and to produce maps portraying landslide susceptibility zonation. Little effort was made to determine where landslides are not expected, where susceptibility is null, or negligible. This is surprising because planners and decision makers are also interesting in knowing where landslides are not foreseen, or cannot occur in an area. We propose a method for the definition of non-susceptible landslide areas, at the synoptic scale. We applied the method in Italy and to the territory surrounding the Mediterranean Sea and we produced two synoptic-scale maps showing areas where landslides are not expected in Italy and in the Mediterranean area. To construct the method we used digital terrain elevation and landslide information. The digital terrain consisted in the 3-arc-second SRTM DEM, the landslide information was obtained for 13 areas in Italy where landslide inventory maps were available to us. We tested three different models to determine the non-susceptible landslide areas, including a linear model (LR), a quantile linear model (QLR), and a quantile non-linear model (QNL). Model performances have been evaluated using independent landslide information represented by the Italian Landslide Inventory (Inventario Fenomeni Franosi in Italia - IFFI). Best results were obtained using the QNL model. The corresponding zonation of non- susceptible landslide areas was intersected in a GIS with geographical census data for Italy. The results show that the 57.5% of the population of Italy (in 2001) was located in areas where landslide susceptibility was expected to be null or negligible, while the remaining 42.5% in areas where some landslide susceptibility was significant or not negligible. We applied the QNL model to the

  20. Landslide-exposed areas modeling using the multivariate analysis

    OpenAIRE

    2004-01-01

    Landslide occurrence is governed by numerous spatial and temporal factors that can be divided into the causes and the triggers. Human interaction with the environment coincides mainly with the triggers, which are also of natural origin. For a better understanding of the causing factors, which mainly influence the spatial distribution, several methods based on GIS technology are used. Results, derived from these methods, define areas that are more exposed to triggering factors, consequencially...

  1. Application of Landsat-8 and ALOS-2 data for structural and landslide hazard mapping in Kelantan, Malaysia

    Science.gov (United States)

    Beiranvand Pour, Amin; Hashim, Mazlan

    2017-07-01

    Identification of high potential risk and susceptible zones for natural hazards of geological origin is one of the most important applications of advanced remote sensing technology. Yearly, several landslides occur during heavy monsoon rainfall in Kelantan River basin, Peninsular Malaysia. Flooding and subsequent landslide occurrences generated significant damage to livestock, agricultural produce, homes and businesses in the Kelantan River basin. In this study, remote sensing data from the recently launched Landsat-8 and Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) on board the Advanced Land Observing Satellite-2 (ALOS-2) were used to map geologic structural and topographical features in the Kelantan River basin for identification of high potential risk and susceptible zones for landslides and flooding areas. The data were processed for a comprehensive analysis of major geological structures and detailed characterizations of lineaments, drainage patterns and lithology at both regional and district scales. The analytical hierarchy process (AHP) approach was used for landslide susceptibility mapping. Several factors such as slope, aspect, soil, lithology, normalized difference vegetation index (NDVI), land cover, distance to drainage, precipitation, distance to fault and distance to the road were extracted from remote sensing satellite data and fieldwork to apply the AHP approach. Directional convolution filters were applied to ALOS-2 data for identifying linear features in particular directions and edge enhancement in the spatial domain. Results indicate that lineament occurrence at regional scale was mainly linked to the N-S trending of the Bentong-Raub Suture Zone (BRSZ) in the west and Lebir Fault Zone in the east of the Kelantan state. The combination of different polarization channels produced image maps that contain important information related to water bodies, wetlands and lithological units. The N-S, NE-SW and NNE-SSW lineament trends and

  2. Riding the storm--landslide danger in the San Francisco Bay Area

    Science.gov (United States)

    Adams, Karen

    2007-01-01

    Movie Synopsis: --A catastrophic 1982 rainstorm triggered 18,000 landslides in the Bay Area, claiming 25 lives and causing $66 million in property damage. --The combination of steep slopes, weak rocks, and intense winter storms make Bay Area uplands an ideal setting for landslides. --Landslides include both swift, potentially deadly debris flows and slower, but destructive deepseated slides. --Learn what USGS scientists have discovered about landslide dynamics and which slopes are most susceptible to sliding. --Hear the devastating stories of Bay Area residents affected by landslides and learn to recognize the danger signs.

  3. Urbanisation of Suweimeh area, Jordan, versus sinkholes and landslides proliferation

    Science.gov (United States)

    Closson, Damien; Abou Karaki, Najib

    2013-04-01

    The Dead Sea is a terminal lake whose level lowers each year of about one meter per year since more than one decade. This is caused mainly by the diversion of surface waters from its watershed. Currently, 1/10 of the Jordan River still reaches the salt lake. The rapid lowering of the lake level does not allow all the surrounding groundwater tables to adjust their level to that of the Dead Sea. This imbalance causes an always faster migration of a part of the groundwater causing underground erosion leading to the formation of sinkholes along the coast, especially where discontinuities, such as faults, are present. The first collapses occurred in the years 1980-90. From the 2000s, in Jordan, they have proliferated to the point of causing serious damages to the facilities of the Arab Potash Company, the agricultural area of Ghor Al Haditha, and more recently the touristic region of Suweimeh. Aware of the problem and the need for gradual rising of the lake level, the Jordanian authorities attended from 2009 to 2011 to the feasibility study of the Red Sea - Dead Sea conduit. Currently, on the one hand, the growing environmental imbalance, and, on the other hand, the desires to develop economic activities along the coast, imply that more goods will be exposed to damages. For example, the area of Wadi Mujib Bridge was rebuilt completely in the late 2000s. It is the same for the 12 km of the dam 18 of an evaporation pond Arab Potash Company. The Numeira Salt Factory was completely destroyed in Ghor Al Haditha and was relocated to Safi. In August 2012, during touristic period, a landslide destroyed half of the Holiday Inn front beach, Suweimeh area ... End of December 2012, a team lead by Prof. Najib Abou Karaki warned the Arab Potash Company of the presence of a circular depression 250 m in diameter within the evaporation pond SP-0A. Although the dike of this saltpan is closely monitored, the exact location and shape of this large sinkhole were not known to the security

  4. 基于小流域的地震扰动区降雨型滑坡泥石流危险性评价方法%Hazard Assessment on Rainfall-Triggered Landslide and Debris Flow in the Seismic Disturbance Area at Watershed Level

    Institute of Scientific and Technical Information of China (English)

    王萌; 姜元俊; 黄栋; 李倩倩

    2015-01-01

    There are many loose slopes existed in the seismic disturbance area .Landslides and debris flow can be easily induced by a heavy or concentrated rainfall .The hazards often occur in a form of chain in an earthquake region with a severer harm than the one caused by a single disaster .In order to evaluate the geological hazards effectively ,we regard the landslide and debris flow as a disaster chain and conduct the analysis synthetically .A coupled model has been developed to assess the hazard degree of debris flow induced by the different 24 h precipitation at watershed level in Baishahe watershed of Dujiangyan City in Sichuan Province .The model comprises of a landslide susceptibility evaluation model ,a stability model , a hydrological model to predict unstable slopes and determine the amount of landslides to be involved , and a statistical model to evaluate the hazard degree of debris flow gully by selecting debris flow volume , frequency ,basin area ,main gully length ,height difference ,cutting density ,and the ratio of unstable gully bed as the evaluation parameters .The results show that the volume of loose material involved in debris flow increase with the intensity of rainfall .However ,when 24 h rainfall is over 200 mm ,the hazard degree of debris flow does not change any more .Among the 17 debris flows ,four debris flows are middle hazardous ,twelve debris flows are high hazardous ,and one debris flow is very high .It indicates that the potential geological hazard is quite serious in the study area .During the rainy season ,17 debris flows might concentratedly outbreak ; which would directly threaten the nearby human lives and properties .The protection engineering and early‐alert should be set to eliminate the hazards caused by the debris flows in comply with the high level fortification standard .By the way ,it’s necessary to take landslide and debris flow as a disaster chain to make the hazard assessment .%地震扰动区存在大量震裂松散

  5. The contribute of DInSAR techniques to landslide hazard evaluation in mountain and hilly regions: a case study from Agno Valley (North-Eastern Italian Alps)

    Science.gov (United States)

    De Agostini, A.; Floris, M.; Pasquali, P.; Barbieri, M.; Cantone, A.; Riccardi, P.; Stevan, G.; Genevois, R.

    2012-04-01

    In the last twenty years, Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques have been widely used to investigate geological processes, such as subsidence, earthquakes and landslides, through the evaluation of earth surface displacements caused by these processes. In the study of mass movements, contribution of interferometry can be limited due to the acquisition geometry of RADAR images and the rough morphology of mountain and hilly regions which represent typical landslide-prone areas. In this study, the advanced DInSAR techniques (i.e. Small Baseline Subset and Persistent Scatterers techniques), available in SARscape software, are used. These methods involve the use of multiple acquisitions stacks (large SAR temporal series) allowing improvements and refinements in landslide identification, characterization and hazard evaluation at the basin scale. Potential and limits of above mentioned techniques are outlined and discussed. The study area is the Agno Valley, located in the North-Eastern sector of Italian Alps and included in the Vicenza Province (Veneto Region, Italy). This area and the entire Vicenza Province were hit by an exceptional rainfall event on November 2010 that triggered more than 500 slope instabilities. The main aim of the work is to verify if spatial information available before the rainfall event, including ERS and ENVISAT RADAR data from 1992 to 2010, were able to predict the landslides occurred in the study area, in order to implement an effectiveness forecasting model. In the first step of the work a susceptibility analysis is carried out using landslide dataset from the IFFI project (Inventario Fenomeni Franosi in Italia, Landslide Italian Inventory) and related predisposing factors, which consist of morphometric (elevation, slope, aspect and curvature) and non-morphometric (land use, distance of roads and distance of river) factors available from the Veneto Region spatial database. Then, to test the prediction, the

  6. Integrating landslide and liquefaction hazard and loss estimates with existing USGS real-time earthquake information products

    Science.gov (United States)

    Tanyas, Hakan

    2017-01-01

    he U.S. Geological Survey (USGS) has made significant progress toward the rapid estimation of shaking and shakingrelated losses through their Did You Feel It? (DYFI), ShakeMap, ShakeCast, and PAGER products. However, quantitative estimates of the extent and severity of secondary hazards (e.g., landsliding, liquefaction) are not currently included in scenarios and real-time post-earthquake products despite their significant contributions to hazard and losses for many events worldwide. We are currently running parallel global statistical models for landslides and liquefaction developed with our collaborators in testing mode, but much work remains in order to operationalize these systems. We are expanding our efforts in this area by not only improving the existing statistical models, but also by (1) exploring more sophisticated, physics-based models where feasible; (2) incorporating uncertainties; and (3) identifying and undertaking research and product development to provide useful landslide and liquefaction estimates and their uncertainties. Although our existing models use standard predictor variables that are accessible globally or regionally, including peak ground motions, topographic slope, and distance to water bodies, we continue to explore readily available proxies for rock and soil strength as well as other susceptibility terms. This work is based on the foundation of an expanding, openly available, case-history database we are compiling along with historical ShakeMaps for each event. The expected outcome of our efforts is a robust set of real-time secondary hazards products that meet the needs of a wide variety of earthquake information users. We describe the available datasets and models, developments currently underway, and anticipated products. 

  7. An integrated approach to earthquake-induced landslide hazard zoning based on probabilistic seismic scenario for Phlegrean Islands (Ischia, Procida and Vivara), Italy

    Science.gov (United States)

    Caccavale, Mauro; Matano, Fabio; Sacchi, Marco

    2017-10-01

    In this study we present an integrated approach to assess earthquake-induced landslide hazard at the source area of the slope instability process. The method has been applied to the case study of Ischia, Procida and Vivara islands that represent an integral part of the Campi Flegrei, a densely populated, active volcanic area, located at the NW margin of the Naples Bay, Italy. The proposed method follows a stepwise procedure including: 1) Probabilistic Seismic Hazard Analysis (PSHA); 2) assessment of site and topographic effects; 3) input of the PSHA outputs into a classic sliding rigid-block analysis for slope instability (Newmark's approach); 4) construction of landslide frequency - magnitude curves for the estimate of the slope failure probability as a function of defined Newmark's threshold values under different probabilistic seismic scenarios; 5) construction of earthquake-induced landslide hazard maps at the source area, based on the integration of the probabilistic approach and the geological, morphological and geotechnical database available for the study area. The Probabilistic Seismic Hazard Analysis (PSHA) is aimed at the definition of the seismic input with different annual exceedance frequency. PSHA results, expressed in terms of Peak Ground Acceleration (PGA) at the bedrock, are calculated for 14 return periods (T) ranging from 10 to 2000 yr. PGA values have been corrected for the site effect associated with geological and morphologic conditions for each selected return period. Secondly, the corrected PGA values have been used as an input for the classic sliding rigid-block Newmark's approach, implemented in a Geographic Information System (GIS) to assess the relative potential for slope failure (landslide susceptibility) both in static (Factor of Safety, FS) and dynamic (Critical acceleration, ac) conditions. The combination of T-dependent, site-corrected PGA with the critical acceleration allowed for the calculation of the expected Newmark

  8. Integrated multi-parameters Probabilistic Seismic Landslide Hazard Analysis (PSLHA): the case study of Ischia island, Italy

    Science.gov (United States)

    Caccavale, Mauro; Matano, Fabio; Sacchi, Marco; Mazzola, Salvatore; Somma, Renato; Troise, Claudia; De Natale, Giuseppe

    2014-05-01

    The Ischia island is a large, complex, partly submerged, active volcanic field located about 20 km east to the Campi Flegrei, a major active volcano-tectonic area near Naples. The island is morphologically characterized in its central part by the resurgent block of Mt. Epomeo, controlled by NW-SE and NE-SW trending fault systems, by mountain stream basin with high relief energy and by a heterogeneous coastline with alternation of beach and tuff/lava cliffs in a continuous reshape due to the weather and sea erosion. The volcano-tectonic process is a main factor for slope stability, as it produces seismic activity and generated steep slopes in volcanic deposits (lava, tuff, pumice and ash layers) characterized by variable strength. In the Campi Flegrei and surrounding areas the possible occurrence of a moderate/large seismic event represents a serious threat for the inhabitants, for the infrastructures as well as for the environment. The most relevant seismic sources for Ischia are represented by the Campi Flegrei caldera and a 5 km long fault located below the island north coast. However those sources are difficult to constrain. The first one due to the on-shore and off-shore extension not yet completely defined. The second characterized only by few large historical events is difficult to parameterize in the framework of probabilistic hazard approach. The high population density, the presence of many infrastructures and the more relevant archaeological sites associated with the natural and artistic values, makes this area a strategic natural laboratory to develop new methodologies. Moreover Ischia represents the only sector, in the Campi Flegrei area, with documented historical landslides originated by earthquake, allowing for the possibility of testing the adequacy and stability of the method. In the framework of the Italian project MON.I.C.A (infrastructural coastlines monitoring) an innovative and dedicated probabilistic methodology has been applied to identify

  9. Performance of Models for Flash Flood Warning and Hazard Assessment: The 2015 Kali Gandaki Landslide Dam Breach in Nepal

    Directory of Open Access Journals (Sweden)

    Jeremy D. Bricker

    2017-02-01

    Full Text Available The 2015 magnitude 7.8 Gorkha earthquake and its aftershocks weakened mountain slopes in Nepal. Co- and postseismic landsliding and the formation of landslide-dammed lakes along steeply dissected valleys were widespread, among them a landslide that dammed the Kali Gandaki River. Overtopping of the landslide dam resulted in a flash flood downstream, though casualties were prevented because of timely evacuation of low-lying areas. We hindcast the flood using the BREACH physically based dam-break model for upstream hydrograph generation, and compared the resulting maximum flow rate with those resulting from various empirical formulas and a simplified hydrograph based on published observations. Subsequent modeling of downstream flood propagation was compromised by a coarse-resolution digital elevation model with several artifacts. Thus, we used a digital-elevation-model preprocessing technique that combined carving and smoothing to derive topographic data. We then applied the 1-dimensional HEC-RAS model for downstream flood routing, and compared it to the 2-dimensional Delft-FLOW model. Simulations were validated using rectified frames of a video recorded by a resident during the flood in the village of Beni, allowing estimation of maximum flow depth and speed. Results show that hydrological smoothing is necessary when using coarse topographic data (such as SRTM or ASTER, as using raw topography underestimates flow depth and speed and overestimates flood wave arrival lag time. Results also show that the 2-dimensional model produces more accurate results than the 1-dimensional model but the 1-dimensional model generates a more conservative result and can be run in a much shorter time. Therefore, a 2-dimensional model is recommended for hazard assessment and planning, whereas a 1-dimensional model would facilitate real-time warning declaration.

  10. Monitoring and modeling conditions for regional shallow landslide initiation in the San Francisco Bay area, California

    Science.gov (United States)

    Collins, B. D.; Stock, J. D.; Godt, J. W.

    2012-12-01

    Bay Hills). In general, this coincides directly with relative precipitation totals in each region (i.e., Marin county typically receives more rainfall over a longer period of time than the East Bay). In those areas that are saturated for longer periods, the shallow landslide hazard is prolonged because these conditions are first needed for storm-related precipitation to subsequently generate positive pore pressure on the failure plane. Both piezometric field measurements and limit equilibrium slope stability analyses indicate that positive pore pressure is required for most shallow landslide failures to occur in the study regions. Based on measurements from two of the sites, our analyses further indicate that at least 2 kPa of pressure is required to trigger shallow landsliding. We measured this pressure at one of our sites in 2011, where more than 30 landslides, including several that mobilized into debris flows, occurred. Additional monitoring at these sites will be used to further constrain and refine antecedent moisture-based thresholds for shallow landslide initiation.

  11. Emergency assessment of seismic landslide susceptibility: a case study of the 2008 Wenchuan earthquake affected area

    Institute of Scientific and Technical Information of China (English)

    Tang Chuan; Zhu Jing; Liang Jingtao

    2009-01-01

    The 8.0 Mw Wenchuan earthquake triggered widespread and large scale landslides in mountainous regions.An approach was used to map and assess landslide susceptibility in a given area. A numerical rating system was applied to five factors that contribute to slope instability. Factors such as lithology, topography, streams and faults have an important influence as event-controlling factors for landslide susceptibility assessment. A final map is provided to show areas of low,medium, and high landslide susceptibility. Areas identified as having high landslide susceptibility were located in the central,northeastern, and far south regions of the study area. The assessment results will help decision makers to select safe sites for emergency placement of refuges and plan for future reconstruction. The maps may also be used as a basis for landslide risk management in the study area.

  12. Geophysical Processes - MO 2013 Landslide Potential St. Louis Area (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Landslide potential is based on slope and lithology. Landslide is considered probable if the slope is 12 percent or greater and correlated with a formation known to...

  13. Rainfall thresholds for forecasting landslides in the Seattle, Washington, area - exceedance and probability

    Science.gov (United States)

    Chleborad, Alan F.; Baum, Rex L.; Godt, Jonathan W.

    2006-01-01

    Empirical rainfall thresholds and related information form a basis for forecasting landslides in the Seattle area. A formula for a cumulative rainfall threshold (CT), P3=3.5-0.67P15, defined by rainfall amounts (in inches) during the last 3 days (72 hours), P3, and the previous 15 days (360 hours), P15, was developed from analysis of historical data for 91 landslides that occurred as part of 3-day events of three or more landslides between 1933 and 1997. Comparison with historical records for 577 landslides (including some used in developing the CT) indicates that the CT captures more than 90 percent of historical landslide events of three or more landslides in 1-day and 3-day periods that were recorded from 1978 to 2003. However, the probability of landslide occurrence on a day when the CT is exceeded at any single rain gage (8.4 percent) is low, and additional criteria are needed to confidently forecast landslide occurrence. Exceedance of a rainfall intensity-duration threshold I=3.257D-1.13, for intensity, I, (inch per hour) and duration, D, (hours), corresponds to a higher probability of landslide occurrence (42 percent at any 3 rain gages or 65 percent at any 10 rain gages), but it predicts fewer landslides. Both thresholds must be used in tandem to forecast landslide occurrence in Seattle.

  14. Human impact on geomorphic processes and hazards in mountain areas in northern Spain

    Science.gov (United States)

    Remondo, Juan; Soto, Jesús; González-Díez, Alberto; Díaz de Terán, José Ramón; Cendrero, Antonio

    2005-03-01

    The temporal occurrence of slope movements, their contribution to relief evolution and human influence on those processes in two study areas of northern Spain are presented. The work is based on temporal analyses covering 100 ka in one study area and 43 years in the other. Temporal analysis has been the basis for quantitatively assessing the magnitude of human influence and developing landslide susceptibility and hazard models with known, independently-tested prediction capability. The results obtained in one study area show a relationship between landsliding periods and increasing precipitation during upper Pleistocene and Holocene. Significant increases of landslide frequency and mobilisation rate were also found around 5500 and 200 years ago. Those moments coincide with two periods of intensified human presence and activities: Neolithic and industrial revolutions. The increase observed represents about one order of magnitude from pre-Neolithic to present. A similar increase has been found between 1954 and 1997 in the other study area. The latter increase shows no relationship with changes in climate parameters or seismic activity. A fairly good correlation has been found between landslide frequency and socioeconomic indicators of human activity. Sedimentation rates in two neighbouring estuaries were determined and significant increases, particularly in the second part of last century, were also found. Evidence obtained suggest that the increases observed in the frequency of slope instability events (and therefore hazard), denudation and sedimentation rates are due to a greater extent to indirect geomorphologic changes caused by human action rather than climate change. Detailed analysis of landslide frequency during that 43-year period has also been used to produce and validate landslide susceptibility models and obtain landslide hazard maps with known prediction accuracy. Validation tests were carried out comparing susceptibility maps based on landslides that

  15. Monitoring Landslides in Western Mountainous Areas of China Using Advanced Multi-Temporal InSAR Techniques

    Science.gov (United States)

    Dong, Jie; Liao, Mingsheng; Zhang, Lu; Gong, Jianya

    2016-08-01

    Disasters, caused by landslide, rock fall, debris flow, ground fissure, etc., are one of the significant natural catastrophes, threatening and influencing the socio-economic conditions around the world. China is one of the countries that suffer heavily from such geo-hazards. And most landslides take place in the mountainous valley areas of western China. With its wide coverage and sub-centimeter accuracy, radar remote sensing has already proven its potential for remotely measuring unstable slopes. Differential InSAR (D-InSAR) is used to recognize known landslides and find potential unstable slopes in a region scale. Then, for a specific landslide, advanced multi-temporal InSAR method is exploited to characterize its surface deformation by obtaining time-series displacement on coherent targets. Among them, the PSI technique exploits only PSs exhibiting high phase stability in a stack of interferograms, which generally exist in urban areas. But, in the case of rural environment characterized by vegetated or low reflectivity homogeneous regions, few PSs could be identified. As a complement of persistent scatterers, distributed scatterers widely existing in rural areas can be exploited. DSs decorrelate slowly and can be found from homogeneous ground, scattered outcrops, debris flows, non-cultivated lands and desert areas. In this poster, a distributed scatterers-based InSAR technique, making use of PSs and DSs, is proposed. At first, we will use D-InSAR technique to detect landslides. Then, both PSI and DS-InSAR will be implemented to monitor interested landslides. And a comparison study of these two methods are conducted.

  16. Variations in population vulnerability to tectonic and landslide-related tsunami hazards in Alaska

    Science.gov (United States)

    Wood, Nathan J.; Peters, Jeff

    2015-01-01

    Effective tsunami risk reduction requires an understanding of how at-risk populations are specifically vulnerable to tsunami threats. Vulnerability assessments primarily have been based on single hazard zones, even though a coastal community may be threatened by multiple tsunami sources that vary locally in terms of inundation extents and wave arrival times. We use the Alaskan coastal communities of Cordova, Kodiak, Seward, Valdez, and Whittier (USA), as a case study to explore population vulnerability to multiple tsunami threats. We use anisotropic pedestrian evacuation models to assess variations in population exposure as a function of travel time out of hazard zones associated with tectonic and landslide-related tsunamis (based on scenarios similar to the 1964 M w9.2 Good Friday earthquake and tsunami disaster). Results demonstrate that there are thousands of residents, employees, and business customers in tsunami hazard zones associated with tectonically generated waves, but that at-risk individuals will likely have sufficient time to evacuate to high ground before waves are estimated to arrive 30–60 min after generation. Tsunami hazard zones associated with submarine landslides initiated by a subduction zone earthquake are smaller and contain fewer people, but many at-risk individuals may not have enough time to evacuate as waves are estimated to arrive in 1–2 min and evacuations may need to occur during earthquake ground shaking. For all hazard zones, employees and customers at businesses far outnumber residents at their homes and evacuation travel times are highest on docks and along waterfronts. Results suggest that population vulnerability studies related to tsunami hazards should recognize non-residential populations and differences in wave arrival times if emergency managers are to develop realistic preparedness and outreach efforts.

  17. Landslide

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA02160 Landslide This large landslide is located within Ganges Chasma. Image information: VIS instrument. Latitude -7.6N, Longitude 315.8E. 17 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  18. Landslide

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA02160 Landslide This large landslide is located within Ganges Chasma. Image information: VIS instrument. Latitude -7.6N, Longitude 315.8E. 17 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  19. Landfill site selection for municipal solid wastes in mountainous areas with landslide susceptibility.

    Science.gov (United States)

    Eskandari, Mahnaz; Homaee, Mehdi; Falamaki, Amin

    2016-06-01

    Several cities across the world are located in mountainous and landslide prone areas. Any landfill siting without considering landslide susceptibility in such regions may impose additional environmental adversity. This study was aimed to propose a practical method for selecting waste disposal site that accounts for landslide exposure. The proposed method was applied to a city which is highly proneness to landslide due to its geology, morphology, and climatic conditions. First, information on the previously occurred landslides of the region was collected. Based on this information, proper landslide causative factors were selected and their thematic maps were prepared. Factors' classes were then standardized in 0-1 domain, and thematic layers were weighted by using analytical hierarchy process (AHP). The landslide susceptibility map was prepared afterwards. Unsuitable areas for landfill location were masked in GIS environment by Boolean method, retaining sufficient areas for further evaluation. Nine remaining alternatives were selected through comprehensive field visits and were ranked by using AHP. Consequently, 17 factors in three environmental, economical, and social perspectives were employed. Sensitivity analyses were performed to assess the stability of the alternatives ranking with respect to variations in criterion weights. Based on the obtained landslide susceptible map, nearly 36 % of the entire region is proneness to landslide. The prepared Boolean map indicates that potential areas for landfill construction cover 11 % of the whole region. The results further indicated that if landslide susceptible areas are not considered in landfill site selection, the potential landfill sites would become more than twice. It can be concluded that if any of these landslide prone sites are selected for landfilling, further environmental disaster would be terminated in the future. It can be further concluded that the proposed method could reasonably well be adjusted to

  20. Cluster analysis of Landslide Vulnerable region on an urban Area in South Korea

    Science.gov (United States)

    Moon, Yonghee; Lee, Sangeun; Kim, Myoungsoo; Baek, Jongrak

    2016-04-01

    Mountain areas occupy about 65% of the territory in South Korea. Due to the rapid population growth and urbanization, many cities suffer from the limitation in space, and hence the commercial buildings, educational facilities, and housing settlement areas continue to stretch until the bottom of the mountain. In result, residents become more and more vulnerable to landslides and debris flow. This led to the central government to perceiving the need for strengthening regulations relevant to urban planning. In order to consider risks due to landslides and debris flow in the stage of urban planning, present authors suggested the strategies, including: first, selecting priority areas necessary to manage landslide-related disasters strictly; second, establishing the integrated management system useful to offer technical assistances to persons in charge of urban planning in the areas; third, promoting disaster awareness programs with those persons along with the central government. As the first attempt, this study mainly discusses the GIS-application procedures in which authors selected the priority areas, which are summarized: 1. Collect the landslide historical data for the period 1999 - 2012 when the disasters particularly threatened the whole country. 2. Define the areas with the one-kilometer radius around the landslide occurrence places. 3. Exclude the areas where population is less than 100 persons per 1 km2. 4. Exclude the areas where mountains with Grade I or II of landslide risk (announced by the Korea Forest Service) go below a certain portion of the area. 5. Carry out the cluster analysis with the remaining areas 6. Classify the types at the standpoint of landslide disaster risk management. Through the procedures, this study obtained a total of 86 priority areas, which were also classified into 24 areas - Type A (high population exposure and mid landslide occurrence likelihood) -, 25 areas - Type B (mid population exposure and high landslide occurrence

  1. Disaster Reduction Decision Support System Against Debris Flows and Landslides Along Highway in Mountainous Area

    Institute of Scientific and Technical Information of China (English)

    LiFa-bin; WeiFang-qiang; CuiPeng; ZhouWan-cun

    2003-01-01

    Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity,simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control engineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Siehuan-Tibet Highway.

  2. Disaster Reduction Decision Support System Against Debris Flows and Landslides Along Highway in Mountainous Area

    Institute of Scientific and Technical Information of China (English)

    Li Fa-bin; Wei Fang-qiang; Cui Peng; Zhou Wan-cun

    2003-01-01

    Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity,simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control ergineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Sichuan-Tibet Highway.

  3. Using high resolution satellite multi-temporal interferometry for landslide hazard detection in tropical environments: the case of Haiti

    Science.gov (United States)

    Wasowski, Janusz; Nutricato, Raffaele; Nitti, Davide Oscar; Bovenga, Fabio; Chiaradia, Maria Teresa; Piard, Boby Emmanuel; Mondesir, Philemon

    2015-04-01

    Synthetic aperture radar (SAR) multi-temporal interferometry (MTI) is one of the most promising satellite-based remote sensing techniques for fostering new opportunities in landslide hazard detection and assessment. MTI is attractive because it can provide very precise quantitative information on slow slope displacements of the ground surface over huge areas with limited vegetation cover. Although MTI is a mature technique, we are only beginning to realize the benefits of the high-resolution imagery that is currently acquired by the new generation radar satellites (e.g., COSMO-SkyMed, TerraSAR-X). In this work we demonstrate the potential of high resolution X-band MTI for wide-area detection of slope instability hazards even in tropical environments that are typically very harsh (eg. coherence loss) for differential interferometry applications. This is done by presenting an example from the island of Haiti, a tropical region characterized by dense and rapidly growing vegetation, as well as by significant climatic variability (two rainy seasons) with intense precipitation events. Despite the unfavorable setting, MTI processing of nearly 100 COSMO-SkyMed (CSK) mages (2011-2013) resulted in the identification of numerous radar targets even in some rural (inhabited) areas thanks to the high resolution (3 m) of CSK radar imagery, the adoption of a patch wise processing SPINUA approach and the presence of many man-made structures dispersed in heavily vegetated terrain. In particular, the density of the targets resulted suitable for the detection of some deep-seated and shallower landslides, as well as localized, very slow slope deformations. The interpretation and widespread exploitation of high resolution MTI data was facilitated by Google EarthTM tools with the associated high resolution optical imagery. Furthermore, our reconnaissance in situ checks confirmed that MTI results provided useful information on landslides and marginally stable slopes that can represent a

  4. GIS and statistical analysis for landslide susceptibility mapping in the Daunia area, Italy

    Directory of Open Access Journals (Sweden)

    F. Mancini

    2010-09-01

    Full Text Available This study focuses on landslide susceptibility mapping in the Daunia area (Apulian Apennines, Italy and achieves this by using a multivariate statistical method and data processing in a Geographical Information System (GIS. The Logistic Regression (hereafter LR method was chosen to produce a susceptibility map over an area of 130 000 ha where small settlements are historically threatened by landslide phenomena. By means of LR analysis, the tendency to landslide occurrences was, therefore, assessed by relating a landslide inventory (dependent variable to a series of causal factors (independent variables which were managed in the GIS, while the statistical analyses were performed by means of the SPSS (Statistical Package for the Social Sciences software. The LR analysis produced a reliable susceptibility map of the investigated area and the probability level of landslide occurrence was ranked in four classes. The overall performance achieved by the LR analysis was assessed by local comparison between the expected susceptibility and an independent dataset extrapolated from the landslide inventory. Of the samples classified as susceptible to landslide occurrences, 85% correspond to areas where landslide phenomena have actually occurred. In addition, the consideration of the regression coefficients provided by the analysis demonstrated that a major role is played by the "land cover" and "lithology" causal factors in determining the occurrence and distribution of landslide phenomena in the Apulian Apennines.

  5. Analysis of rainfall-triggered landslide hazards through the dynamic integration of remotely sensed, modeled and in situ environmental factors in El Salvador

    Science.gov (United States)

    Anderson, Eric Ross

    Landslides pose a persistent threat to El Salvador's population, economy and environment. Government officials share responsibility in managing this hazard by alerting populations when and where landslides may occur as well as developing and enforcing proper land use and zoning practices. This thesis addresses gaps in current knowledge between identifying precisely when and where slope failures may initiate and outlining the extent of the potential debris inundation areas. Improvements on hazard maps are achieved by considering a series of environmental variables to determine causal factors through spatial and temporal analysis techniques in Geographic Information Systems and remote sensing. The output is a more dynamic tool that links high resolution geomorphic and hydrological factors to daily precipitation. Directly incorporable into existing decision support systems, this allows for better disaster management and is transferable to other developing countries.

  6. A new approach to evaluating landslide hazard in the mountain glacial environment - mass and hypsometry

    Science.gov (United States)

    Reid, Madison L.; Evans, Stephen G.

    2016-04-01

    The magnitude and frequency of glacial hazards is central to the discussion of the effect of climate change in the mountain glacial environment and has persisted as a research question since the 1990s. We propose a new approach to evaluating mass flow (including landslides) hazard in the glacier environment conditioned by temporal and elevation changes in glacier-ice loss. Using digital topographic data sets and InSAR techniques we investigate the hypsometry of ice loss in a well-defined glacial environment in the southwest Coast Mountains of SW British Columbia (the Mount Meager Volcanic Complex - MMVC). The volume and elevation of major mass movements that have taken place in the MMVC since the 1930s is established and compared to the volume and hypsometry of glacial ice loss in the same time period. In the analysis, the volumes of ice loss and landslides are converted to units of mass. The elevation of a sequence of large-scale mass movements do not suggest a close correlation with the elevation or temporal sequence of greatest ice loss. Instead, the temporal relationship between the mass of ice loss and mass lost from slopes in landslides (including ice, rock, and debris) is suggestive of a steady state. The same approach is then applied to the Cordillera Blanca (Peruvian Andes) where we show that the greatest mass moved from the glacier system by glacier-related mass flows since the 1930s, corresponded generally to the period of greatest ice loss suggesting a decay-based response to recent glacier ice loss. As in the MMVC, the elevation of mass flow events is not correlated with the estimated hypsometry of glacial ice loss; in both regions the largest landslide in the period investigated occurred from a high mountain peak defining a topographic divide and where ice loss was minimal. It thus appears that mountain glacial environments exhibit different landslide responses to glacier ice loss that may be conditioned by the rate of ice loss and strongly influenced

  7. A Case Study of Geologic Hazards Affecting School Buildings: Evaluating Seismic Structural Vulnerability and Landslide Hazards at Schools in Aizawl, India

    Science.gov (United States)

    Perley, M. M.; Guo, J.

    2016-12-01

    India's National School Safety Program (NSSP) aims to assess all government schools in earthquake prone regions of the country. To supplement the Mizoram State Government's recent survey of 141 government schools, we screened an additional 16 private and 4 government schools for structural vulnerabilities due to earthquakes, as well as landslide hazards, in Mizoram's capital of Aizawl. We developed a geomorphologically derived landslide susceptibility matrix, which was cross-checked with Aizawl Municipal Corporation's landslide hazard map (provided by Lettis Consultants International), to determine the geologic hazards at each school. Our research indicates that only 7% of the 22 assessed school buildings are located within low landslide hazard zones; 64% of the school buildings, with approximately 9,500 students, are located within very high or high landslide hazard zones. Rapid Visual Screening (RVS) was used to determine the structural earthquake vulnerability of each school building. RVS is an initial vulnerability assessment procedure used to inventory and rank buildings that may be hazardous during an earthquake. Our study indicates that all of the 22 assessed school buildings have a damageability rating of Grade 3 or higher on the 5-grade EMS scale, suggesting a significant vulnerability and potential for damage in buildings, ranging from widespread cracking of columns and beam column joints to collapse. Additionally, 86% of the schools we visited had reinforced concrete buildings constructed before Aizawl's building regulations were passed in 2007, which can be assumed to lack appropriate seismic reinforcement. Using our findings, we will give recommendations to the Government of Mizoram to prevent unnecessary loss of life by minimizing each school's landslide risk and ensuring schools are earthquake-resistant.

  8. Non-susceptible landslide areas in Italy and in the Mediterranean region

    Science.gov (United States)

    Marchesini, I.; Ardizzone, F.; Alvioli, M.; Rossi, M.; Guzzetti, F.

    2014-08-01

    We used landslide information for 13 study areas in Italy and morphometric information obtained from the 3-arcseconds shuttle radar topography mission digital elevation model (SRTM DEM) to determine areas where landslide susceptibility is expected to be negligible in Italy and in the landmasses surrounding the Mediterranean Sea. The morphometric information consisted of the local terrain slope which was computed in a square 3 × 3-cell moving window, and in the regional relative relief computed in a circular 15 × 15-cell moving window. We tested three different models to classify the "non-susceptible" landslide areas, including a linear model (LNR), a quantile linear model (QLR), and a quantile, non-linear model (QNL). We tested the performance of the three models using independent landslide information presented by the Italian Landslide Inventory (Inventario Fenomeni Franosi in Italia - IFFI). Best results were obtained using the QNL model. The corresponding zonation of non-susceptible landslide areas was intersected in a geographic information system (GIS) with geographical census data for Italy. The result determined that 57.5% of the population of Italy (in 2001) was located in areas where landslide susceptibility is expected to be negligible. We applied the QNL model to the landmasses surrounding the Mediterranean Sea, and we tested the synoptic non-susceptibility zonation using independent landslide information for three study areas in Spain. Results showed that the QNL model was capable of determining where landslide susceptibility is expected to be negligible in the validation areas in Spain. We expect our results to be applicable in similar study areas, facilitating the identification of non-susceptible landslide areas, at the synoptic scale.

  9. Polarimetric Scattering Properties of Landslides in Forested Areas and the Dependence on the Local Incidence Angle

    Directory of Open Access Journals (Sweden)

    Takashi Shibayama

    2015-11-01

    Full Text Available This paper addresses the local incidence angle dependence of several polarimetric indices corresponding to landslides in forested areas. Landslide is deeply related to the loss of human lives and their property. Various kinds of remote sensing techniques, including aerial photography, high-resolution optical satellite imagery, LiDAR and SAR interferometry (InSAR, have been available for landslide investigations. SAR polarimetry is potentially an effective measure to investigate landslides because fully-polarimetric SAR (PolSAR data contain more information compared to conventional single- or dual-polarization SAR data. However, research on landslide recognition utilizing polarimetric SAR (PolSAR is quite limited. Polarimetric properties of landslides have not been examined quantitatively so far. Accordingly, we examined the polarimetric scattering properties of landslides by an assessment of how the decomposed scattering power components and the polarimetric correlation coefficient change with the local incidence angle. In the assessment, PolSAR data acquired from different directions with both spaceborne and airborne SARs were utilized. It was found that the surface scattering power and the polarimetric correlation coefficient of landslides significantly decrease with the local incidence angle, while these indices of surrounding forest do not. This fact leads to establishing a method of effective detection of landslide area by polarimetric information.

  10. Landslide properties Controlled by the Denudation degree on Granite area in Japan

    Science.gov (United States)

    Matsuzawa, Makoto; Takahara, Teruyoshi; Kinoshita, Atsuhiko; Ishizuka, Tadanori

    2014-05-01

    In 2009, numerous shallow landslides were induced in a cretaceous granite region by heavy rainstorms in the area of the city of Hofu, Yamaguchi Prefecture, in western Japan. Fourteen people were killed by the debris flow. This area has a widely distributed plantation surface, and topography formed by denudation processes such as the 2009 landslides. The plantation surface area is known for the frequent occurrence of landslides in the past. However, the relation between the landslide properties and the degree of mountain denudation, which is important for predicting the landslide risk, has not been clarified. We examined the relation between the degree of mountain denudation and the shallow landslide properties [landslide density (number/km2), landslide form, and soil layer structure]. First, we classified the slopes based on the degree of mountain denudation and interpretation of the 2009 landslide scars, using 1-m resolution DEMs, aerial photographs, and field surveys. As a result, the slopes were classified into three types as follows: (1) lightly denuded slopes (L-slope), (2) moderately denuded slopes (M-slope), and (3) heavily denuded slopes (H-slope). The landslide numbers were 23, 54, and 21 in the L-slope, M-slope, and H-slope regions, respectively. Next, we analyzed the landslide properties using ESRI ArcGIS10. The landslide densities were 77/ km2, 115/ km2, and 41/ km2 in the L-slope, M-slope, and H-slope areas, respectively. The investigation area experienced heavy precipitation (about 250-300 mm per day). The landslide average volumes were 423 m3, 401 m3, and 173 m3 in the L-slope, M-slope, and H-slope areas, respectively. The landslide average angles were 28.5° , 33.2° , and 40.4° in the L-slope, M-slope, and H-slope areas, respectively. Finally, we surveyed the landslide form and soil layer structure using detailed field surveys. The landslide form in the L-slope and M-slope areas was that of an 'arc shape type', and in the H-slope area was that of

  11. SINMAP Modeling of an active landslide area in the Swabian Alb

    Science.gov (United States)

    Terhorst, Birgit; Jaeger, Daniel

    2015-04-01

    Landslides are a common hazard in German low mountain areas such as the Swabian Alb. As areas of former landslides are highly prone to secondary movements, this study aims to assess the susceptibility for landslide hazard around Mössingen-Öschingen, a region consistently affected by landslides during the last decades. Based on the history and development of mass movements and a detailed geomorphological map, slope stability was calculated using SINMAP (Stability Index Mapping). SINMAP (Pack et al., 1998; Tarboton, 1997) is based on the "infinite slope stability model" by Hammond et al. (1992) and Montgomery and Dietrich (1994) describing the ratio of slope stabilizing factors (e.g. cohesion) and slope destabilizing factors (e.g. gravitation) on a slip surface parallel to the slope. Most input parameters are determined by the relief and therefore, can be calculated from a digital terrain model (DTM, resolution 5 m). Based on the local morphology and geology, a total of 10 'calibration regions', each with similar hydrogeological characteristics, were defined. Further input parameters were: Shear strength via friction angle (Phi), cohesion (C) and hydraulic conductivity (T/R). The data was obtained from soil mechanical assessments and field/laboratory analyses. As a result, a specific stability index is calculated, describing the susceptibility of a slope movement. In a first step, the 'topographic wetness index' (derived from catchment area, slope gradient and hydraulic conductivity) was calculated. Results show several preferred (natural) drainage channels with generally higher water saturations in morphological depressions. Several of them can be linked to the location of damaged houses in the settlement area on the lower slope. The SINMAP calculation clearly revealed the impermeable Callovian clay layers as most prone to slope movements. A comparison of the susceptibility map with slide masses which were mapped during a field survey showed generally good

  12. Shallow Landslide Susceptibilty Mapping using SINMAP for Selected Areas in the Philippines

    Science.gov (United States)

    Rabonza, M. L.; Alejandrino, I. A.; Suarez, J.; Aquino, D. T.; Eco, R. C.; Lagmay, A.

    2013-12-01

    Among the deadliest calamities that plagued the Philippines were the landslide and flooding caused by consecutive tropical storms Mufia, Merbok, Winnie, and Nanmadol in Infanta, Quezon (2004), Typhoon Reming in Guinsaugon, Leyte (2006) and Typhoon Pepeng in Pangasinan (2009). In Quezon alone, the number of death and missing exceeded 1600, and the cost of damage was estimated at US$78.2M. Situated in the humid tropics, the Philippines will inevitably be a locus of climate-related disasters similar to those experienced recently. To aid the local government units in delineating areas located on hazardous zones in the country, the spatial distribution of rainfall-induced shallow landslide susceptibilities was modeled for the provinces of Quezon (906,960 ha), Leyte (651,505 ha), and Pangasinan (545,101 ha). The Stability INdex Mapping (SINMAP) model was applied based on the infinite slope stability model and a steady-state hydrology module. Using the hydrologic, soil and topographic parameters for each pixel on a 6-meter synthetic aperture radar-derived DEM (digital elevation model grid) or on a 1-meter LiDAR-derived DEM, Stability Index Maps were generated for the study areas. Soil properties were based on data available from Bureau of Soils and Water Management as of July 2013. These data were augmented by field data and constrained by values from direct shear strength testing, soil gradation, and hydraulic conductivity tests of soil. The model validation performed using the previously identified landslide inventory was found out to be about 90% accurate. The SINMAP model accuracy can be further improved by additional locations for field tests to better map out the spatial variation of soil properties.

  13. Landslides

    Science.gov (United States)

    2003-01-01

    [figure removed for brevity, see original site] The slumping of materials in the walls of this impact crater illustrate the continued erosion of the martian surface. Small fans of debris as well as larger landslides are observed throughout the THEMIS image.Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.Image information: VIS instrument. Latitude 40.9, Longitude 120.5 East (239.5 West). 19 meter/pixel resolution.

  14. 14 CFR 417.413 - Hazard areas.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Hazard areas. 417.413 Section 417.413 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Ground Safety § 417.413 Hazard areas. (a) General. A launch operator...

  15. 46 CFR 120.530 - Hazardous areas.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hazardous areas. 120.530 Section 120.530 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150... Systems and Requirements § 120.530 Hazardous areas. (a) Electrical equipment in lockers used to...

  16. 46 CFR 183.530 - Hazardous areas.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Hazardous areas. 183.530 Section 183.530 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) ELECTRICAL INSTALLATION Miscellaneous Systems and Requirements § 183.530 Hazardous areas. (a)...

  17. 46 CFR 129.520 - Hazardous areas.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hazardous areas. 129.520 Section 129.520 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ELECTRICAL INSTALLATIONS Miscellaneous Electrical Systems § 129.520 Hazardous areas. (a) No OSV that carries flammable or...

  18. Estancia Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  19. Elephant Butte Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  20. Sierra County Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  1. Development of a system for landslide risk assessment for Cuba

    NARCIS (Netherlands)

    Castellanos Abella, E.A.; Westen, C.J. van

    2005-01-01

    In many developing countries, such as Cuba, landslide-affected areas are not systematically mapped in a national inventory and no “regional to local” approach for landslide hazard and risk assessment has been carried out so far. Most of the conventional landslide studies in Cuba are qualitative in n

  2. Development of a system for landslide risk assessment for Cuba

    NARCIS (Netherlands)

    Castellanos Abella, E.A.; Westen, C.J. van

    2005-01-01

    In many developing countries, such as Cuba, landslide-affected areas are not systematically mapped in a national inventory and no “regional to local” approach for landslide hazard and risk assessment has been carried out so far. Most of the conventional landslide studies in Cuba are qualitative in

  3. Prediction of the area affected by earthquake-induced landsliding based on seismological parameters

    Science.gov (United States)

    Marc, Odin; Meunier, Patrick; Hovius, Niels

    2017-07-01

    We present an analytical, seismologically consistent expression for the surface area of the region within which most landslides triggered by an earthquake are located (landslide distribution area). This expression is based on scaling laws relating seismic moment, source depth, and focal mechanism with ground shaking and fault rupture length and assumes a globally constant threshold of acceleration for onset of systematic mass wasting. The seismological assumptions are identical to those recently used to propose a seismologically consistent expression for the total volume and area of landslides triggered by an earthquake. To test the accuracy of the model we gathered geophysical information and estimates of the landslide distribution area for 83 earthquakes. To reduce uncertainties and inconsistencies in the estimation of the landslide distribution area, we propose an objective definition based on the shortest distance from the seismic wave emission line containing 95 % of the total landslide area. Without any empirical calibration the model explains 56 % of the variance in our dataset, and predicts 35 to 49 out of 83 cases within a factor of 2, depending on how we account for uncertainties on the seismic source depth. For most cases with comprehensive landslide inventories we show that our prediction compares well with the smallest region around the fault containing 95 % of the total landslide area. Aspects ignored by the model that could explain the residuals include local variations of the threshold of acceleration and processes modulating the surface ground shaking, such as the distribution of seismic energy release on the fault plane, the dynamic stress drop, and rupture directivity. Nevertheless, its simplicity and first-order accuracy suggest that the model can yield plausible and useful estimates of the landslide distribution area in near-real time, with earthquake parameters issued by standard detection routines.

  4. Development and research on the GIS-based landslide prediction system of the Three Gorges area

    Science.gov (United States)

    Ge, Qiao; Tang, Zhongshi; Wang, Haiwei

    2008-10-01

    In this paper we discussed the development and research of the GIS-based landslide prediction system of the Three Gorges area. First of all, we systematically revisited the basic issues of the landslide prediction, including the principles of landslide prediction, the division of sliding-time and sliding-deformation stages, prediction parameters selection and monitoring sites selection. In addition to reviewing the landslide prediction models, this paper detailed discussed an improved model which makes an integration of the results of multiple prediction models. On the basis of those landslide prediction models, we developed a GIS-based landslide prediction system by using Visual C#.NET and ESRI ArcObjects components. Finally, this paper selected two typical landslide cases in the Three Gorges area: the Xintan landslide and the Lianzi Cliff dangerous rock body, and used the system to calculate and analyze. It validated the applicability and accuracy of the prediction models, made a test of the practicality of the system, and achieved good results.

  5. Assessment of tsunami hazard to the U.S. East Coast using relationships between submarine landslides and earthquakes

    Science.gov (United States)

    ten Brink, U.S.; Lee, H.J.; Geist, E.L.; Twichell, D.

    2009-01-01

    Submarine landslides along the continental slope of the U.S. Atlantic margin are potential sources for tsunamis along the U.S. East coast. The magnitude of potential tsunamis depends on the volume and location of the landslides, and tsunami frequency depends on their recurrence interval. However, the size and recurrence interval of submarine landslides along the U.S. Atlantic margin is poorly known. Well-studied landslide-generated tsunamis in other parts of the world have been shown to be associated with earthquakes. Because the size distribution and recurrence interval of earthquakes is generally better known than those for submarine landslides, we propose here to estimate the size and recurrence interval of submarine landslides from the size and recurrence interval of earthquakes in the near vicinity of the said landslides. To do so, we calculate maximum expected landslide size for a given earthquake magnitude, use recurrence interval of earthquakes to estimate recurrence interval of landslide, and assume a threshold landslide size that can generate a destructive tsunami. The maximum expected landslide size for a given earthquake magnitude is calculated in 3 ways: by slope stability analysis for catastrophic slope failure on the Atlantic continental margin, by using land-based compilation of maximum observed distance from earthquake to liquefaction, and by using land-based compilation of maximum observed area of earthquake-induced landslides. We find that the calculated distances and failure areas from the slope stability analysis is similar or slightly smaller than the maximum triggering distances and failure areas in subaerial observations. The results from all three methods compare well with the slope failure observations of the Mw = 7.2, 1929 Grand Banks earthquake, the only historical tsunamigenic earthquake along the North American Atlantic margin. The results further suggest that a Mw = 7.5 earthquake (the largest expected earthquake in the eastern U

  6. Volcanic hazard management in dispersed volcanism areas

    Science.gov (United States)

    Marrero, Jose Manuel; Garcia, Alicia; Ortiz, Ramon

    2014-05-01

    Traditional volcanic hazard methodologies were developed mainly to deal with the big stratovolcanoes. In such type of volcanoes, the hazard map is an important tool for decision-makers not only during a volcanic crisis but also for territorial planning. According to the past and recent eruptions of a volcano, all possible volcanic hazards are modelled and included in the hazard map. Combining the hazard map with the Event Tree the impact area can be zoned and defining the likely eruptive scenarios that will be used during a real volcanic crisis. But in areas of disperse volcanism is very complex to apply the same volcanic hazard methodologies. The event tree do not take into account unknown vents, because the spatial concepts included in it are only related with the distance reached by volcanic hazards. The volcanic hazard simulation is also difficult because the vent scatter modifies the results. The volcanic susceptibility try to solve this problem, calculating the most likely areas to have an eruption, but the differences between low and large values obtained are often very small. In these conditions the traditional hazard map effectiveness could be questioned, making necessary a change in the concept of hazard map. Instead to delimit the potential impact areas, the hazard map should show the expected behaviour of the volcanic activity and how the differences in the landscape and internal geo-structures could condition such behaviour. This approach has been carried out in La Palma (Canary Islands), combining the concept of long-term hazard map with the short-term volcanic scenario to show the expected volcanic activity behaviour. The objective is the decision-makers understand how a volcanic crisis could be and what kind of mitigation measurement and strategy could be used.

  7. A multi-annual landslide inventory for the assessment of shallow landslide susceptibility - Two test cases in Vorarlberg, Austria

    Science.gov (United States)

    Zieher, Thomas; Perzl, Frank; Rössel, Monika; Rutzinger, Martin; Meißl, Gertraud; Markart, Gerhard; Geitner, Clemens

    2016-04-01

    Geomorphological landslide inventories provide crucial input data for any study on the assessment of landslide susceptibility, hazard or risk. Several approaches for assessing landslide susceptibility have been proposed to identify areas particularly vulnerable to this natural hazard. What they have in common is the need for data of observed landslides. Therefore the first step of any study on landslide susceptibility is usually the compilation of a geomorphological landslide inventory using a geographical information system. Recent research has proved the feasibility of orthophoto interpretation for the preparation of an inventory aimed at the delineation of landslides with the use of distinctive signs in the imagery data. In this study a multi-annual landslide inventory focusing on shallow landslides (i.e. translational soil slides of 0-2 m in depth) was compiled for two study areas in Vorarlberg (Austria) from the interpretation of nine orthophoto series. In addition, derivatives of two generations of airborne laser scanning data aided the mapping procedure. Landslide scar areas were delineated on the basis of a high-resolution differential digital terrain model. The derivation of landslide volumes, depths and depth-to-length ratios are discussed. Results show that most mapped landslides meet the definition of a shallow landslide. The inventory therefore provides the data basis for the assessment of shallow landslide susceptibility and allows for the application of various modelling techniques.

  8. Application of remote monitoring technology in landslides in the Luoshan mining area

    Energy Technology Data Exchange (ETDEWEB)

    Man-chao He; Zhi-gang Tao; Bin Zhang [China University of Mining & Technology, Beijing (China). Research Center of Geotechnical Engineering

    2009-09-15

    With the scale extending of mining, the landslide disaster in the earth's surface will become more and more serious, and these landslide disasters are being threatened to the sustainable safe mining of the underground mine and the open-pit mine. Based on the theory that sliding force is greater than the shear resistance (resisting force) at the potential slip surface is the necessary and sufficient condition to occur the landslide as the sliding criterion, the principle and method for sliding force remote monitoring is presented, and the functional relationship between the human mechanical quantity and the natural sliding force is derived, hereby, the natural sliding force can be calculated according to the human mechanical quantity. Based on above principle and method, a new system of landslide remote monitoring is designed and 53 systems are installed on the landslide body in the Luoshan mining area, which make up the landslide remote monitoring network. According to the results of field test around 8 months, monitoring curves between sliding force and time are obtained, which can describe and forecast the develop trend of landslide. According to above analysis, the results show that this system has some following advantages: (1) real-time monitoring; (2) remote intelligent transmission; (3) landslides early warning. 11 refs., 8 figs., 1 tab.

  9. Application of remote monitoring technology in landslides in the Luoshan mining area

    Institute of Scientific and Technical Information of China (English)

    HE Man-chao; TAO Zhi-gang; ZHANG Bin

    2009-01-01

    With the scale extending of mining, the landslide disaster in the earth's surface will become more and more serious, and these landslide disasters are being threatened to the sustainable safe mining of the underground mine and the open-pit mine. Based on the theory that sliding force is greater than the shear resistance (resisting force) at the potential slip surface is the necessary and sufficient condition to occur the landslide as the sliding criterion, the principle and method for sliding force remote monitoring is presented, and the functional relationship between the human mechanical quantity and the natural sliding force is derived, hereby, the natural sliding force can be calculated according to the human mechanical quantity. Based on above principle and method, a new system of landslide remote monitoring is designed and 53 systems are installed on the landslide body in the Luoshan mining area, which make up the landslide remote monitoring network. According to the results of field test around 8 months, monitoring curves between sliding force and time are obtained, which can describe and forecast the develop trend of landslide. According to above analysis, the results show that this system has some following advantages: (1) real-time monitoring; (2) remote intelligent transmission; (3) landslides early warning.

  10. Assessment of Landslide Susceptibility by Decision Trees in the Metropolitan Area of Istanbul, Turkey

    Directory of Open Access Journals (Sweden)

    H. A. Nefeslioglu

    2010-01-01

    Full Text Available The main purpose of the present study is to investigate the possible application of decision tree in landslide susceptibility assessment. The study area having a surface area of 174.8 km2 locates at the northern coast of the Sea of Marmara and western part of Istanbul metropolitan area. When applying data mining and extracting decision tree, geological formations, altitude, slope, plan curvature, profile curvature, heat load and stream power index parameters are taken into consideration as landslide conditioning factors. Using the predicted values, the landslide susceptibility map of the study area is produced. The AUC value of the produced landslide susceptibility map has been obtained as 89.6%. According to the results of the AUC evaluation, the produced map has exhibited a good enough performance.

  11. Assessment and Risk Zonation of Landslides in Panxi Area Based on 3S Technology

    Institute of Scientific and Technical Information of China (English)

    ZHANG Baolei; SONG Shujun; FENG Wenlan; ZHOU Wancun

    2006-01-01

    Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce landslides such as the elevation,the slope, the vegetation cover,the lithology,the rainfall and so on are gained using GIS(geographical information system) techniques of spatial analysis. All the data obtained are managed through building landslide management system. At the same time,the system is made the platform to appraise the relationship between the distribution of landslides and the environmental factors. The results indicate: landslides take place relatively easily in the slope range between 10° and 25°; most landslides are in the mixed area of bush and grass with a coverage degree of from 20% to 65%; the distribution of landslides has a positive relationship with the distribution of annual rainfall. The risk degree of Panxi Area is zoned and mapped by the model of liner stack using GIS technique,and the result indicates: the place of high risk degree is the belt of Panzhihua-Miyi-Dechang-Mugu and southeast of Huili county and Huidong county,and area is about 512 707 hm2.

  12. A Multidisciplinary Approach for Monitoring Flood and Landslide Hazards: Application to The Quebrada de Ramón Watershed in Central Chile.

    Science.gov (United States)

    Contreras Vargas, M. T.; Oberli, C.; Castro, L. M.; Ledezma, C., Sr.; Gironas, J. A.; Escauriaza, C. R.

    2016-12-01

    Floods and landslides produced by heavy rainfall in the Andes have acquired new relevance due to recent large-scale events, which have had devastating consequences. The complexity of the geomorphology and the climate that characterizes this region promote the occurrence of flash floods with high sediment concentrations. In addition, cities are expanding in the Andean foothills, occupying the floodplains, and increasing the exposure of the population and infrastructure to floods and landslides. Performing a hazard assessment of extreme events in these regions is a very complex task, due to the great uncertainty associated to the factors controlling the dynamics of floods and landslides, and the lack of historical records of hydrometeorological variables. The analysis is further complicated by anthropic activities that can amplify the effects of these events, and by the influence of climate change and the ENSO phenomenon. To provide a better understanding of these events in Andean regions, we integrate knowledge from different disciplines to study various aspects associated to floods and landslides in the Quebrada de Ramón, an Andean watershed located in central Chile. We combine two methodologies to collect the information in the field: 1) We use traditional methods, including sediment samples, weather stations, and topographic data from aerial photography and LIDAR; and 2) We also implement innovative methods based on a wireless network of sensors for monitoring hydrometeorological variables in real-time. We employ this information to develop and couple weather forecast, hydrological and hydrodynamic models, which are used to predict the propagation of floods in the river channel and the urban area, as well as the occurrence of landslides on specific sections of the watershed. This work is expected to provide more reliable information to citizens, city planners, emergency managers and other decision makers to enhance the preparedness, response, and resilience of

  13. Connectivity of earthquake-triggered landslides with the fluvial network: Implications for landslide sediment transport after the 2008 Wenchuan earthquake

    Science.gov (United States)

    Li, Gen; West, A. Joshua; Densmore, Alexander L.; Hammond, Douglas E.; Jin, Zhangdong; Zhang, Fei; Wang, Jin; Hilton, Robert G.

    2016-04-01

    Evaluating the influence of earthquakes on erosion, landscape evolution, and sediment-related hazards requires understanding fluvial transport of material liberated in earthquake-triggered landslides. The location of landslides relative to river channels is expected to play an important role in postearthquake sediment dynamics. In this study, we assess the position of landslides triggered by the Mw 7.9 Wenchuan earthquake, aiming to understand the relationship between landslides and the fluvial network of the steep Longmen Shan mountain range. Combining a landslide inventory map and geomorphic analysis, we quantify landslide-channel connectivity in terms of the number of landslides, landslide area, and landslide volume estimated from scaling relationships. We observe a strong spatial variability in landslide-channel connectivity, with volumetric connectivity (ξ) ranging from ~20% to ~90% for different catchments. This variability is linked to topographic effects that set local channel densities, seismic effects (including seismogenic faulting) that regulate landslide size, and substrate effects that may influence both channelization and landslide size. Altogether, we estimate that the volume of landslides connected to channels comprises 43 + 9/-7% of the total coseismic landslide volume. Following the Wenchuan earthquake, fine-grained (90% of the total landslide volume) may be more significantly affected by landslide locations.

  14. Quick Analysis Method for Estimating Debris Flow Prone Area Caused by Overflow from Landslide dam

    Science.gov (United States)

    Shimizu, T.; Uchida, T.; Yamakoshi, T.; Yoshino, K.; Kisa, H.; Ishizuka, T.; Kaji, A.

    2012-04-01

    When earthquake or torrential rainfall cause deep catastrophic landslides, landslide dams can be formed in mountainous region. If water overflows from the landslide dams, large scale debris flow can occurs and possibly causes serious disasters in the downward region. Debris flow caused by the overflow from landslide dam is possible to affect the larger area than normal debris flow and flash flood. It is important for both a decision maker and resident in the area to recognize the disaster prone area as early as possible. For that reason, it is important to establish a quick analysis method for estimating debris flow prone area caused by overflow from landslide dams under the emergency situation. This situation requires the method to have both accuracy and speed for release. Nonetheless these two factors have trade-off relationship. We recently developed the quick analysis method to estimate debris flow disaster prone area caused by overflow from landslide dams. The method including the ways of efficient survey and numerical simulation programs called QUAD-L (QUick Analysis system for Debris flow caused by Landslide dam overflow). Our quick analysis system was actually applied to show the area for evacuation against debris flow caused by overflow from landslide dam formed by the 2011 Typhoon Talas which hit mainly the central region of Japan on September 2-4th, 2011. In addition to background of this application, since May 1st, 2011, Erosion and Sediment Control (SABO) Department of the Ministry of Land, Infrastructure, Transport and Tourism, Japan (MLIT) launched a new scheme using above-mentioned quick analysis method.

  15. Monitoring of Landslide Areas with the Use of Contemporary Methods of Measuring and Mapping

    Science.gov (United States)

    Skrzypczak, Izabela; Kogut, Janusz; Kokoszka, Wanda; Zientek, Dawid

    2017-03-01

    In recent years, there is an increase of landslide risk observed, which is associated with intensive anthropogenic activities and extreme weather conditions. Appropriate monitoring and proper development of measurements resulting as maps of areas at risk of landslides enables us to estimate the risk in the social and economic aspect. Landslide monitoring in the framework of SOPO project is performed by several methods of measurements: monitoring of surface (GNSS measurement and laser scanning), monitoring in-deepth (inclinometer measurements) and monitoring of the hydrological changes and precipitation (measuring changes in water-table and rainfall).

  16. Monitoring of Landslide Areas with the Use of Contemporary Methods of Measuring and Mapping

    Directory of Open Access Journals (Sweden)

    Skrzypczak Izabela

    2017-03-01

    Full Text Available In recent years, there is an increase of landslide risk observed, which is associated with intensive anthropogenic activities and extreme weather conditions. Appropriate monitoring and proper development of measurements resulting as maps of areas at risk of landslides enables us to estimate the risk in the social and economic aspect. Landslide monitoring in the framework of SOPO project is performed by several methods of measurements: monitoring of surface (GNSS measurement and laser scanning, monitoring in-deepth (inclinometer measurements and monitoring of the hydrological changes and precipitation (measuring changes in water-table and rainfall.

  17. Large-area landslide susceptibility with optimized slope-units

    Science.gov (United States)

    Alvioli, Massimiliano; Marchesini, Ivan; Reichenbach, Paola; Rossi, Mauro; Ardizzone, Francesca; Fiorucci, Federica; Guzzetti, Fausto

    2017-04-01

    A Slope-Unit (SU) is a type of morphological terrain unit bounded by drainage and divide lines that maximize the within-unit homogeneity and the between-unit heterogeneity across distinct physical and geographical boundaries [1]. Compared to other terrain subdivisions, SU are morphological terrain unit well related to the natural (i.e., geological, geomorphological, hydrological) processes that shape and characterize natural slopes. This makes SU easily recognizable in the field or in topographic base maps, and well suited for environmental and geomorphological analysis, in particular for landslide susceptibility (LS) modelling. An optimal subdivision of an area into a set of SU depends on multiple factors: size and complexity of the study area, quality and resolution of the available terrain elevation data, purpose of the terrain subdivision, scale and resolution of the phenomena for which SU are delineated. We use the recently developed r.slopeunits software [2,3] for the automatic, parametric delineation of SU within the open source GRASS GIS based on terrain elevation data and a small number of user-defined parameters. The software provides subdivisions consisting of SU with different shapes and sizes, as a function of the input parameters. In this work, we describe a procedure for the optimal selection of the user parameters through the production of a large number of realizations of the LS model. We tested the software and the optimization procedure in a 2,000 km2 area in Umbria, Central Italy. For LS zonation we adopt a logistic regression model implemented in an well-known software [4,5], using about 50 independent variables. To select the optimal SU partition for LS zonation, we want to define a metric which is able to quantify simultaneously: (i) slope-unit internal homogeneity (ii) slope-unit external heterogeneity (iii) landslide susceptibility model performance. To this end, we define a comprehensive objective function S, as the product of three

  18. 反距离加权法在区域滑坡危险性评价中的应用%Application of Inverse Distance Weighted Method to Regional Landslide Hazards Assessment

    Institute of Scientific and Technical Information of China (English)

    朱吉祥; 张礼中; 周小元; 梁国玲; 王乾; 蔡子昭

    2012-01-01

    区域滑坡危险性评价是进行区域滑坡风险性研究的基础。提出了一种基于反距离加权的"黑箱"式评价方法,该方法将滑坡作为一个系统进行分析,各影响因素作为滑坡系统中的子系统。根据相似相近的原理,假设已有滑坡点对周围区域的滑坡危险性存在局部性影响,利用反距离加权法对所有滑坡点进行分析评价,以获取研究区的滑坡危险性评价结果。同时对该方法运用于区域滑坡危险性评价的理论基础、适用范围进行分析,并以四川省苍溪县为例,验证了运用该方法进行区域滑坡危险性评价的可行性。%Regional landslide hazards assessment is the basis of the research on regional landslide hazard risk.A "black box" method is proposed based on inverse distance weighted interpolation(IDW) theory considering landslide as a system and the factors as subsystems.This approach hypothesizes that existing landslides have local influences on the landslide risk to their surrounding areas according to the principle that the more closed the distance of the things is,the more similar the characters of them are;it obtains the result of regional landslide hazard assessment by analyzing all the landslides with the IDW theory;and simultaneously,it analyzes the basis of theory why the IDW theory can be applied in regional landslide hazards assessment and the scope of its application.Finally,the feasibility of IDW Interpolation theory in regional landslide hazards assessment is verified by taking Cangxi County of Sichuan Province for an example.

  19. APPLICATION OF PALSAR-2 REMOTE SENSING DATA FOR LANDSLIDE HAZARD MAPPING IN KELANTAN RIVER BASIN, PENINSULAR MALAYSIA

    Directory of Open Access Journals (Sweden)

    A. Beiranvand Pour

    2016-06-01

    Full Text Available Yearly, several landslides ensued during heavy monsoons rainfall in Kelantan river basin, peninsular Malaysia, which are obviously connected to geological structures and topographical features of the region. In this study, the recently launched Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2 onboard the Advanced Land Observing Satellite-2 (ALOS-2, remote sensing data were used to map geological structural and topographical features in the Kelantan river basin for identification of high potential risk and susceptible zones for landslides. Adaptive Local Sigma filter was selected and applied to accomplish speckle reduction and preserving both edges and features in PALSAR-2 fine mode observation images. Different polarization images were integrated to enhance geological structures. Additionally, directional filters were applied to the PALSAR-2 Local Sigma resultant image for edge enhancement and detailed identification of linear features. Several faults, drainage patterns and lithological contact layers were identified at regional scale. In order to assess the results, fieldwork and GPS survey were conducted in the landslide affected zones in the Kelantan river basin. Results demonstrate the most of the landslides were associated with N-S, NNW-SSE and NE-SW trending faults, angulated drainage pattern and metamorphic and Quaternary units. Consequently, structural and topographical geology maps were produced for Kelantan river basin using PALSAR-2 data, which could be broadly applicable for landslide hazard mapping.

  20. Application of PALSAR-2 Remote Sensing Data for Landslide Hazard Mapping in Kelantan River Basin, Peninsular Malaysia

    Science.gov (United States)

    Beiranvand Pour, Amin; Hashim, Mazlan

    2016-06-01

    Yearly, several landslides ensued during heavy monsoons rainfall in Kelantan river basin, peninsular Malaysia, which are obviously connected to geological structures and topographical features of the region. In this study, the recently launched Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) onboard the Advanced Land Observing Satellite-2 (ALOS-2), remote sensing data were used to map geological structural and topographical features in the Kelantan river basin for identification of high potential risk and susceptible zones for landslides. Adaptive Local Sigma filter was selected and applied to accomplish speckle reduction and preserving both edges and features in PALSAR-2 fine mode observation images. Different polarization images were integrated to enhance geological structures. Additionally, directional filters were applied to the PALSAR-2 Local Sigma resultant image for edge enhancement and detailed identification of linear features. Several faults, drainage patterns and lithological contact layers were identified at regional scale. In order to assess the results, fieldwork and GPS survey were conducted in the landslide affected zones in the Kelantan river basin. Results demonstrate the most of the landslides were associated with N-S, NNW-SSE and NE-SW trending faults, angulated drainage pattern and metamorphic and Quaternary units. Consequently, structural and topographical geology maps were produced for Kelantan river basin using PALSAR-2 data, which could be broadly applicable for landslide hazard mapping.

  1. Landslide triggering-thickness susceptibility, a simple proxy for landslide hazard? A test in the Mili catchment (North-Eastern Sicily, Italy)

    Science.gov (United States)

    Lombardo, Luigi; Fubelli, Giandomenico; Amato, Gabriele; Bonasera, Mauro; Mai, Martin

    2016-04-01

    in order to produce an example for a landslide triggering-thickness susceptibility which differently from more common approaches, may performs as a better proxy for more complex landslide hazard assessments.

  2. Landslide susceptibility assessment based on different rainfall-triggered landslide events

    Science.gov (United States)

    Oliveira, Sergio C.; Zêzere, José L.; Garcia, Ricardo A. C.

    2015-04-01

    the landslide-event inventory not used to assess landslide susceptibility. Results and discussion are further supported by Receiver Operator Characteristic curves and the corresponding Area Under the Curve. This work was supported by the FCT - Portuguese Foundation for Science and Technology and is within the framework of the Project Pan-European and nation-wide landslide susceptibility assessment, European and Mediterranean Major Hazards Agreement (EUR-OPA). The first author was funded by a postdoctoral grant (SFRH/BPD/85827/2012) from the Portuguese Foundation for Science and Technology (FCT).

  3. Landslides in West Coast metropolitan areas: The role of extreme weather events

    Directory of Open Access Journals (Sweden)

    Michela Biasutti

    2016-12-01

    That a news-based catalog of landslides is accurate enough to allow the identification of different landslide/rainfall relationships in the major urban areas along the US West Coast suggests that this technology can potentially be used for other English-language cities and could become an even more powerful tool if expanded to other languages and non-traditional news sources, such as social media.

  4. Validating the operational bias and hypothesis of universal exponent in landslide frequency-area distribution.

    Science.gov (United States)

    Huang, Jr-Chuan; Lee, Tsung-Yu; Teng, Tse-Yang; Chen, Yi-Chin; Huang, Cho-Ying; Lee, Cheing-Tung

    2014-01-01

    The exponent decay in landslide frequency-area distribution is widely used for assessing the consequences of landslides and with some studies arguing that the slope of the exponent decay is universal and independent of mechanisms and environmental settings. However, the documented exponent slopes are diverse and hence data processing is hypothesized for this inconsistency. An elaborated statistical experiment and two actual landslide inventories were used here to demonstrate the influences of the data processing on the determination of the exponent. Seven categories with different landslide numbers were generated from the predefined inverse-gamma distribution and then analyzed by three data processing procedures (logarithmic binning, LB, normalized logarithmic binning, NLB and cumulative distribution function, CDF). Five different bin widths were also considered while applying LB and NLB. Following that, the maximum likelihood estimation was used to estimate the exponent slopes. The results showed that the exponents estimated by CDF were unbiased while LB and NLB performed poorly. Two binning-based methods led to considerable biases that increased with the increase of landslide number and bin width. The standard deviations of the estimated exponents were dependent not just on the landslide number but also on binning method and bin width. Both extremely few and plentiful landslide numbers reduced the confidence of the estimated exponents, which could be attributed to limited landslide numbers and considerable operational bias, respectively. The diverse documented exponents in literature should therefore be adjusted accordingly. Our study strongly suggests that the considerable bias due to data processing and the data quality should be constrained in order to advance the understanding of landslide processes.

  5. Validating the operational bias and hypothesis of universal exponent in landslide frequency-area distribution.

    Directory of Open Access Journals (Sweden)

    Jr-Chuan Huang

    Full Text Available The exponent decay in landslide frequency-area distribution is widely used for assessing the consequences of landslides and with some studies arguing that the slope of the exponent decay is universal and independent of mechanisms and environmental settings. However, the documented exponent slopes are diverse and hence data processing is hypothesized for this inconsistency. An elaborated statistical experiment and two actual landslide inventories were used here to demonstrate the influences of the data processing on the determination of the exponent. Seven categories with different landslide numbers were generated from the predefined inverse-gamma distribution and then analyzed by three data processing procedures (logarithmic binning, LB, normalized logarithmic binning, NLB and cumulative distribution function, CDF. Five different bin widths were also considered while applying LB and NLB. Following that, the maximum likelihood estimation was used to estimate the exponent slopes. The results showed that the exponents estimated by CDF were unbiased while LB and NLB performed poorly. Two binning-based methods led to considerable biases that increased with the increase of landslide number and bin width. The standard deviations of the estimated exponents were dependent not just on the landslide number but also on binning method and bin width. Both extremely few and plentiful landslide numbers reduced the confidence of the estimated exponents, which could be attributed to limited landslide numbers and considerable operational bias, respectively. The diverse documented exponents in literature should therefore be adjusted accordingly. Our study strongly suggests that the considerable bias due to data processing and the data quality should be constrained in order to advance the understanding of landslide processes.

  6. Landslide monitoring at hillside residential area using GPS static and inclinometer techniques

    Science.gov (United States)

    Othman, Z.; Wan Aziz, W. A.; Anuar, A.

    2012-04-01

    Landslide is one of prominent geohazards that continuously affecting the tropical countries including Malaysia. Frequent occurrences of landslides at hillslopes during the heavy rainy periods have resulted in public fear for the safety of their life and properties. For the past 25 years, many landslides have occurrences have been reported in Klang Valley especially at the hilly terrain residential areas. A landslide monitoring scheme is therefore very crucial and should be carried out continuously. Various studies have been conducted to monitor landslide activities such as conventional geotechnical and geodetic techniques. Each of these techniques has its own advantages and limitations. Therefore, this study focuses on the effectiveness of the combination approach of GPS technology and inclinometer techniques for landslide monitoring. The study area is located at residential area Section 5, Wangsa Maju, Kuala Lumpur, Malaysia. The inclinometer instrument has been placed at five (5) selected monitoring points and three (3) epochs of inclinometer measurements were made. At the same time, the GPS observations have also been carried out for three (3) epochs separately using GPS static techniques. This GPS network consists of four (4) control points and eleven (11) monitoring points. The GPS observations data were validated, processed and adjusted using two (2) adjustment software namely Trimble Geomatic Office (TGO) version 1.6, and GPS Adjustment and Deformation Analysis (GADA). The results have shown that the GPS technique can be implemented with inclinometer technique to detect horizontal displacements up to +/- 30 mm and vertical displacements less than +/- 50 mm.

  7. A tool for the estimation of the distribution of landslide area in R

    Science.gov (United States)

    Rossi, M.; Cardinali, M.; Fiorucci, F.; Marchesini, I.; Mondini, A. C.; Santangelo, M.; Ghosh, S.; Riguer, D. E. L.; Lahousse, T.; Chang, K. T.; Guzzetti, F.

    2012-04-01

    We have developed a tool in R (the free software environment for statistical computing, http://www.r-project.org/) to estimate the probability density and the frequency density of landslide area. The tool implements parametric and non-parametric approaches to the estimation of the probability density and the frequency density of landslide area, including: (i) Histogram Density Estimation (HDE), (ii) Kernel Density Estimation (KDE), and (iii) Maximum Likelihood Estimation (MLE). The tool is available as a standard Open Geospatial Consortium (OGC) Web Processing Service (WPS), and is accessible through the web using different GIS software clients. We tested the tool to compare Double Pareto and Inverse Gamma models for the probability density of landslide area in different geological, morphological and climatological settings, and to compare landslides shown in inventory maps prepared using different mapping techniques, including (i) field mapping, (ii) visual interpretation of monoscopic and stereoscopic aerial photographs, (iii) visual interpretation of monoscopic and stereoscopic VHR satellite images and (iv) semi-automatic detection and mapping from VHR satellite images. Results show that both models are applicable in different geomorphological settings. In most cases the two models provided very similar results. Non-parametric estimation methods (i.e., HDE and KDE) provided reasonable results for all the tested landslide datasets. For some of the datasets, MLE failed to provide a result, for convergence problems. The two tested models (Double Pareto and Inverse Gamma) resulted in very similar results for large and very large datasets (> 150 samples). Differences in the modeling results were observed for small datasets affected by systematic biases. A distinct rollover was observed in all analyzed landslide datasets, except for a few datasets obtained from landslide inventories prepared through field mapping or by semi-automatic mapping from VHR satellite imagery

  8. Application of Time Series Insar Technique for Deformation Monitoring of Large-Scale Landslides in Mountainous Areas of Western China

    Science.gov (United States)

    Qu, T.; Lu, P.; Liu, C.; Wan, H.

    2016-06-01

    Western China is very susceptible to landslide hazards. As a result, landslide detection and early warning are of great importance. This work employs the SBAS (Small Baseline Subset) InSAR Technique for detection and monitoring of large-scale landslides that occurred in Li County, Sichuan Province, Western China. The time series INSAR is performed using descending scenes acquired from TerraSAR-X StripMap mode since 2014 to get the spatial distribution of surface displacements of this giant landslide. The time series results identify the distinct deformation zone on the landslide body with a rate of up to 150mm/yr. The deformation acquired by SBAS technique is validated by inclinometers from diverse boreholes of in-situ monitoring. The integration of InSAR time series displacements and ground-based monitoring data helps to provide reliable data support for the forecasting and monitoring of largescale landslide.

  9. A hybrid fuzzy weight of evidence method in landslide susceptibility analysis on the Wuyuan area, China

    Science.gov (United States)

    Hong, Haoyuan; Ilia, Ioanna; Tsangaratos, Paraskevas; Chen, Wei; Xu, Chong

    2017-08-01

    The present study proposed a hybrid fuzzy weight of evidence model for constructing a landslide susceptibility map in the Wuyuan area, China, where disastrous landslide events have occurred. The model combines the knowledge of experts obtained through a fuzzy logic approach and a hybrid weight of evidence method. The estimated knowledge-based fuzzy membership value of each environmental variable is combined with data-based conditional probabilities to derive fuzzy posterior probabilities and landslide susceptibility. The developed model was compared with a landslide susceptibility map produced using the data-driven weight of evidence method, based on 510 landslide and non-landslide sites. The sites were identified by analyzing airborne imagery, field investigation and previous studies. Landside susceptibility for these sites was analyzed using 10 geo-environmental variables: slope, aspect, lithology, soil, rainfall, plan curvature, the normalized difference vegetation index, distance to roads, distance to rivers and distance to faults. The resultant hybrid fuzzy weight of evidence method showed high predictive power, with the area under the success and predictive curves being 0.770 and 0.746, respectively. Additional analyses showed that the developed model could work effectively even with limited data.

  10. The efficacy of a programme of landslide risk reduction in areas of unplanned housing in the Eastern Caribbean.

    Science.gov (United States)

    Anderson, Malcolm G; Holcombe, Elizabeth; Esquivel, Maricarmen; Toro, Joaquin; Ghesquiere, Francis

    2010-04-01

    Poor countries are disproportionately affected by the cost of disasters. Yet there is evidence of the benefits of seeking to mitigate the impact of a disaster, compared with the costs incurred in 'making good' after a major event has occurred. This article reviews a programme of landslide risk reduction in unplanned communities in the Eastern Caribbean. The construction of appropriate surface water management measures, based on the application of scientific and engineering principles, has been demonstrated to reduce the hazard from rainfall-triggered landslides. Adopting a community-based approach additionally delivers social and environmental benefits relating to employment generation, improvements in the environmental conditions within the community, and improvements slope management practices. The sustained implementation of the community-based projects has provided the necessary evidence-base for these practices to influence Government policy and practice, and gain recognition from regional development agencies. The strategic and incremental uptake of the community-based methodology is demonstrated to be an effective means for delivering physical landslide risk reduction measures in the most 'at risk' areas of unplanned housing.

  11. Fertility Effects of Retained Trees with Vegetation Development on Landslide Area

    Directory of Open Access Journals (Sweden)

    Yi-Chang Chen

    2014-01-01

    Full Text Available Typhoon Aere, of Taiwan in 2004, caused landslides of Shihmen reservoir watershed of Sule creek, and this damaged area was recovered with hydro-seeding vegetation engineering forming three retained trees island on the slopeland in 2006. This study investigated the fertility effect of retained trees for vegetation development on landslide area. The relevant results that the Rhodes grass is the dominant plant and near the three retained trees area, 192 trees for 18 species, which sources of seeds are carried and spread by wind and wildlife, increases in this landslide area from 2006 to 2013, meanwhile, the tree island is getting formed. The three trees islands change micro-climate, and they gather nutrients and moisture as much as possible so that the vegetation community could develop from tree island area to external side gradually.

  12. Combined rock slope stability and shallow landslide susceptibility assessment of the Jasmund cliff area (Rügen Island, Germany

    Directory of Open Access Journals (Sweden)

    A. Günther

    2009-05-01

    Full Text Available In this contribution we evaluated both the structurally-controlled failure susceptibility of the fractured Cretaceous chalk rocks and the topographically-controlled shallow landslide susceptibility of the overlying glacial sediments for the Jasmund cliff area on Rügen Island, Germany. We employed a combined methodology involving spatially distributed kinematical rock slope failure testing with tectonic fabric data, and both physically- and inventory-based shallow landslide susceptibility analysis. The rock slope failure susceptibility model identifies areas of recent cliff collapses, confirming its value in predicting the locations of future failures. The model reveals that toppling is the most important failure type in the Cretaceous chalk rocks of the area. The shallow landslide susceptibility analysis involves a physically-based slope stability evaluation which utilizes material strength and hydraulic conductivity data, and a bivariate landslide susceptibility analysis exploiting landslide inventory data and thematic information on ground conditioning factors. Both models show reasonable success rates when evaluated with the available inventory data, and an attempt was made to combine the individual models to prepare a map displaying both terrain instability and landslide susceptibility. This combination highlights unstable cliff portions lacking discrete landslide areas as well as cliff sections highly affected by past landslide events. Through a spatial integration of the rock slope failure susceptibility model with the combined shallow landslide assessment we produced a comprehensive landslide susceptibility map for the Jasmund cliff area.

  13. Integration of landslide susceptibility products in the environmental plans

    Science.gov (United States)

    Fiorucci, Federica; Reichenbach, Paola; Rossi, Mauro; Cardinali, Mauro; Guzzetti, Fausto

    2015-04-01

    Landslides are one of the most destructive natural hazard that causes damages to urban area worldwide. The knowledge of where a landslide could occur is essential for the strategic management of the territory and for a good urban planning . In this contest landslide susceptibility zoning (LSZ) is crucial to provide information on the degree to which an area can be affected by future slope movements. Despite landslide susceptibility maps have been prepared extensively during the last decades, there are few examples of application is in the environmental plans (EP). In this work we present a proposal for the integration of the landslide inventory map with the following landslide susceptibility products: (i) landslide susceptibility zonation , (ii) the associated error map and (iii) the susceptibility uncertainty map. Moreover we proposed to incorporate detailed morphological studies for the evaluation of landslide risk associated to local parceling plan. The integration of all this information is crucial for the management of landslide risk in urban expansions forecasts. Municipality, province and regional administration are often not able to support the costs of landslide risk evaluation for extensive areas but should concentrate their financial resources to specific hazardous and unsafe situations defined by the result of the integration of landslide susceptibility products. Zonation and detail morphological analysis should be performed taking into account the existing laws and regulations, and could become a starting point to discuss new regulations for the landslide risk management.

  14. Landslides at Qingjiang River in the Downstream Area of Shuibuya Dam Site, China

    Institute of Scientific and Technical Information of China (English)

    Kallen D; Xiang Wei; Ehret D; Rohn J

    2006-01-01

    To enhance the general knowledge of landslides in China, the DAAD (German Academic mapped to gather information concerning landslides and their correlation to lithology, slope angles and texture. The geological mapping contained the characterization of the lithologicai units. The characterization of the shape of landslides and the classification of rocks into units with similar geotechnical behavior is contained in the geotechnical map. Samples were taken and investigated using X-ray diffraction to identify the clay minerals and geotechnical tests to determine the effective shear angle and cohesion of rocks and soils. Geotechnical mapping showed a close connection between lithology, slope angle and texture concerning the occurrence of landslides. Most landslides occur on the northern bank of the Qingjiang River where the dip angle of the bedding is nearly parallel to the slope, resulting in potential and effective slide planes. On the southern bank only sporadic and small landslides occur because the bedding is antipodal to the slope angle. This pilot work is a base for further and more detailed investigations in this area.

  15. Landslide Mapping in Vegetated Areas Using Change Detection Based on Optical and Polarimetric SAR Data

    Directory of Open Access Journals (Sweden)

    Simon Plank

    2016-04-01

    Full Text Available Mapping of landslides, quickly providing information about the extent of the affected area and type and grade of damage, is crucial to enable fast crisis response, i.e., to support rescue and humanitarian operations. Most synthetic aperture radar (SAR data-based landslide detection approaches reported in the literature use change detection techniques, requiring very high resolution (VHR SAR imagery acquired shortly before the landslide event, which is commonly not available. Modern VHR SAR missions, e.g., Radarsat-2, TerraSAR-X, or COSMO-SkyMed, do not systematically cover the entire world, due to limitations in onboard disk space and downlink transmission rates. Here, we present a fast and transferable procedure for mapping of landslides, based on change detection between pre-event optical imagery and the polarimetric entropy derived from post-event VHR polarimetric SAR data. Pre-event information is derived from high resolution optical imagery of Landsat-8 or Sentinel-2, which are freely available and systematically acquired over the entire Earth’s landmass. The landslide mapping is refined by slope information from a digital elevation model generated from bi-static TanDEM-X imagery. The methodology was successfully applied to two landslide events of different characteristics: A rotational slide near Charleston, West Virginia, USA and a mining waste earthflow near Bolshaya Talda, Russia.

  16. LANDSLIDES INCIDENCE IN THE PIEDMONT OF BAIA MARE URBAN AREA (CASE STUDIES

    Directory of Open Access Journals (Sweden)

    S. ZAHARIA

    2012-12-01

    Full Text Available The landslides incidence in the piedmont of baia mare urbana area cae studies. The General Urban Plan (GUP of Baia Mare municipality requires the study of expected susceptibility for landslides in order to build infrastructure within sustainable development conditions. The complexity and diversity of local geographic area factors, strongly affected by the human pressure, favours the triggering and extension of slope processes in the municipality’s piedmont area. To prevent some major imbalances it is imperative to implement some adequate measures based on in-depth studies.

  17. Indirect economic impact of landslide hazards by disruption to national road transportation networks; Scotland, United Kingdom.

    Science.gov (United States)

    Postance, Benjamin; Hillier, John; Dijkstra, Tom; Dixon, Neil

    2016-04-01

    The failure of engineered or natural slopes which support or are adjacent to transportation systems often inflicts costly direct physical damage and indirect system disruption. The consequences and severity of indirect impacts vary according to which links, nodes or network facilities are physically disrupted. Moreover, it is often the case that multiple slope failure disruptions are triggered simultaneously following prolonged or intense precipitation events due to a degree of local homogeneity of slope characteristics and materials. This study investigates the application of national commuter statistics and network agent simulation to evaluate indirect impacts of landslide events disrupting the Scottish trunk road transportation network (UK). Previous studies often employ shortest pathway analysis whereas agent simulation has received relatively little attention. British Geological Survey GeoSure landslide susceptibility data is used to select 35 susceptible trunk road segments by means of neighbouring total area at risk. For each of the candidate 35 segments the network and zonal variation in travel time is calculated for a single day of disruption, economic impact is approximated using established governmental and industry transport planning and appraisal values. The results highlight that a number of trunk road segments incur indirect economic losses in the order of tens of thousands of pounds for each day of closure. Calculated losses at the A83 Rest and Be Thankful are 50% greater than previous estimates at £75 thousand per day of closure. Also highlighted are events in which economic impact is relatively minor, yet concentrating on particular communities that can become substantially isolated as a consequence of a single event. The findings of this study are of interest and support wider investigations exploring cost considerations for decision makers and mitigation strategies, in addition to identifying network topological and demand indicators conducive

  18. Enhancing national Daily Landslide Hazard Assessments through inter-agency collaboration; lessons learned from storm Desmond (UK)/Synne (Norway), Dec 2015.

    Science.gov (United States)

    Boje, Søren; Devoli, Graziella; Sund, Monica; Freeborough, Katy; Dijkstra, Tom; Reeves, Helen; Banks, Vanessa

    2016-04-01

    The Norwegian Water Resources and Energy Directorate (NVE) and the British Geological Survey (BGS) compile daily landslide hazard assessments (DLHA) in their respective countries. NVE DLHA has been operational since 2013 and provides national daily assessments based on quantitative thresholds related to daily hydro-meteorological forecasts coupled with qualitative expert analysis of these forecasts. The BGS DLHA has been operational since 2012 and this is predominantly based on expert evaluation of antecedent hydro-meteorological conditions and triggering rainfall across Great Britain (GB). In both cases, the hydro-meteorological evaluation is coupled with observations derived from proprietary datasets on landslide events and landslide potential in order to specify, and limit, the spatial extent of the potentially impacted area. However, the DLHA are strongly driven by hydro-meteorological forecasts. In December 2015, a large extra-tropical cyclone developed over the Atlantic and delivered record-breaking precipitation over parts of the UK and Norway. The meteorological services started naming these events to enhance public uptake and awareness and the storms were named as Desmond (the 4th large storm in 2015/16 in the UK) and Synne (the 5th storm in 2015 in Norway). Desmond arrived in earnest on the 5th of December and brought intense precipitation and strong winds over a 48-hour period. In Cumbria (NW-England) record precipitation was measured (341.4 mm in 24-hour at Honister Pass which is more than twice the monthly average), with 48-hour accumulations exceeding 400 mm. Synne arrived shortly after in Norway and was also characterised by excessive rainfall of 140 mm in 24-hour, 236 mm in 48-hour and 299 mm in 72-hour at Maudal, SW-Norway. Both organisations managed to issue appropriate advance warnings, operating individually. In Norway, warnings were issued some 2 days in advance with a yellow level communicated on Friday 4th and an orange warning the 5th and 6

  19. Analysis on Two Typical Landslide Hazard Phenomena in The Wenchuan Earthquake by Field Investigations and Shaking Table Tests

    Directory of Open Access Journals (Sweden)

    Changwei Yang

    2015-08-01

    Full Text Available Based on our field investigations of landslide hazards in the Wenchuan earthquake, some findings can be reported: (1 the multi-aspect terrain facing empty isolated mountains and thin ridges reacted intensely to the earthquake and was seriously damaged; (2 the slope angles of most landslides was larger than 45°. Considering the above disaster phenomena, the reasons are analyzed based on shaking table tests of one-sided, two-sided and four-sided slopes. The analysis results show that: (1 the amplifications of the peak accelerations of four-sided slopes is stronger than that of the two-sided slopes, while that of the one-sided slope is the weakest, which can indirectly explain the phenomena that the damage is most serious; (2 the amplifications of the peak accelerations gradually increase as the slope angles increase, and there are two inflection points which are the point where the slope angle is 45° and where the slope angle is 50°, respectively, which can explain the seismic phenomenon whereby landslide hazards mainly occur on the slopes whose slope angle is bigger than 45°. The amplification along the slope strike direction is basically consistent, and the step is smooth.

  20. Analysis on Two Typical Landslide Hazard Phenomena in The Wenchuan Earthquake by Field Investigations and Shaking Table Tests.

    Science.gov (United States)

    Yang, Changwei; Zhang, Jianjing; Liu, Feicheng; Bi, Junwei; Jun, Zhang

    2015-08-06

    Based on our field investigations of landslide hazards in the Wenchuan earthquake, some findings can be reported: (1) the multi-aspect terrain facing empty isolated mountains and thin ridges reacted intensely to the earthquake and was seriously damaged; (2) the slope angles of most landslides was larger than 45°. Considering the above disaster phenomena, the reasons are analyzed based on shaking table tests of one-sided, two-sided and four-sided slopes. The analysis results show that: (1) the amplifications of the peak accelerations of four-sided slopes is stronger than that of the two-sided slopes, while that of the one-sided slope is the weakest, which can indirectly explain the phenomena that the damage is most serious; (2) the amplifications of the peak accelerations gradually increase as the slope angles increase, and there are two inflection points which are the point where the slope angle is 45° and where the slope angle is 50°, respectively, which can explain the seismic phenomenon whereby landslide hazards mainly occur on the slopes whose slope angle is bigger than 45°. The amplification along the slope strike direction is basically consistent, and the step is smooth.

  1. Application of Enhanced-2D-CWT in Topographic Images for Mapping Landslide Risk Areas

    CERN Document Server

    Valenzuela, V V Vermehren; de Oliveira, H M

    2015-01-01

    There has been lately a number of catastrophic events of landslides and mudslides in the mountainous region of Rio de Janeiro, Brazil. Those were caused by intense rain in localities where there was unplanned occupation of slopes of hills and mountains. Thus, it became imperative creating an inventory of landslide risk areas in densely populated cities. This work presents a way of demarcating risk areas by using the bidimensional Continuous Wavelet Transform (2D-CWT) applied to high resolution topographic images of the mountainous region of Rio de Janeiro.

  2. Debris Flow Simulation using FLO-2D on the 2004 Landslide Area of Real, General Nakar, and Infanta, Philippines

    Science.gov (United States)

    Llanes, F.; dela Resma, M.; Ferrer, P.; Realino, V.; Aquino, D. T.; Eco, R. C.; Lagmay, A.

    2013-12-01

    From November 14 to December 3, 2004, Luzon Island was ravaged by 4 successive typhoons: Typhoon Mufia, Tropical Storm Merbok, Tropical Depression Winnie, and Super Typhoon Nanmadol. Tropical Depression Winnie was the most destructive of the four when it triggered landslides on November 29 that devastated the municipalities of Infanta, General Nakar, and Real in Quezon Province, southeast Luzon. Winnie formed east of Central Luzon on November 27 before it moved west-northwestward over southeastern Luzon on November 29. A total of 1,068 lives were lost and more than USD 170 million worth of damages to crops and infrastructure were incurred from the landslides triggered by Typhoon Winnie on November 29 and the flooding caused by the 4 typhoons. FLO-2D, a flood routing software for generating flood and debris flow hazard maps, was utilized to simulate the debris flows that could potentially affect the study area. Based from the rainfall intensity-duration-frequency analysis, the cumulative rainfall from typhoon Winnie on November 29 which was approximately 342 mm over a 9-hour period was classified within a 100-year return period. The Infanta station of the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) was no longer able to measure the amount of rainfall after this period because the rain gauge in that station was washed away by floods. Rainfall data with a 100-year return period was simulated over the watersheds delineated from a SAR-derived digital elevation model. The resulting debris flow hazard map was compared with results from field investigation and previous studies made on the landslide event. The simulation identified 22 barangays (villages) with a total of 45,155 people at risk of turbulent flow and flooding.

  3. A multidisciplinary methodological approach for slope stability assessment of an area prone to shallow landslides

    Science.gov (United States)

    Bordoni, Massimiliano; Meisina, Claudia; Valentino, Roberto; Bittelli, Marco; Battista Bischetti, Gian; Vercesi, Alberto; Chersich, Silvia; Giuseppina Persichillo, Maria

    2016-04-01

    Rainfall-induced shallow landslides are widespread slope instabilities phenomena in several hilly and mountainous contexts all over the world. Due to their high density of diffusion also in small areas, they can provoke important damages to terrains, infrastructures, buildings, and, sometimes, loss of human lives. Shallow landslides affect superficial soils of limited thickness (generally lower than 2 m), located above weathered or not bedrock levels. Their triggering mechanism is strictly linked to the hydrological response of the soils to rainfall events. Thus, it becomes fundamental a comprehensive analysis of the soil properties which can influence the susceptibility of a slope to shallow landslides. In this study, a multidisciplinary approach was followed for the characterization of the soils and the individuation of the triggering conditions in an area particularly prone to shallow failures, for slope stability assessment. This area corresponded to the hilly sector of North-Eastern Oltrepò Pavese (Lombardy Region, Northern Italy), where the density of shallow landslides is really high, reaching more than 36 landslides per km2. The soils of the study area were analyzed through a multidisciplinary characterization, which took into account for the main geotechnical, mechanical and mineralogical parameters and also for the main pedological features of the materials. This approach allowed for identifying the main features and the horizons which could influence the soil behavior in relation to the conditions that are preparatory to shallow landslides development. In a test-site slope, representative of the main geomorphological, geological and landslides distribution characteristics typical of the study area, a continuous in time monitoring of meteorological (rainfall amount, air temperature, air humidity, atmospheric pressure, net solar radiation, wind speed and direction) and hydrological (soil water content, pore water pressure) parameters was implemented. In

  4. Catastrophic debris flows transformed from landslides in volcanic terrains : mobility, hazard assessment and mitigation strategies

    Science.gov (United States)

    Scott, Kevin M.; Macias, Jose Luis; Naranjo, Jose Antonio; Rodriguez, Sergio; McGeehin, John P.

    2001-01-01

    Communities in lowlands near volcanoes are vulnerable to significant volcanic flow hazards in addition to those associated directly with eruptions. The largest such risk is from debris flows beginning as volcanic landslides, with the potential to travel over 100 kilometers. Stratovolcanic edifices commonly are hydrothermal aquifers composed of unstable, altered rock forming steep slopes at high altitudes, and the terrain surrounding them is commonly mantled by readily mobilized, weathered airfall and ashflow deposits. We propose that volcano hazard assessments integrate the potential for unanticipated debris flows with, at active volcanoes, the greater but more predictable potential of magmatically triggered flows. This proposal reinforces the already powerful arguments for minimizing populations in potential flow pathways below both active and selected inactive volcanoes. It also addresses the potential for volcano flank collapse to occur with instability early in a magmatic episode, as well as the 'false-alarm problem'-the difficulty in evacuating the potential paths of these large mobile flows. Debris flows that transform from volcanic landslides, characterized by cohesive (muddy) deposits, create risk comparable to that of their syneruptive counterparts of snow and ice-melt origin, which yield noncohesive (granular) deposits, because: (1) Volcano collapses and the failures of airfall- and ashflow-mantled slopes commonly yield highly mobile debris flows as well as debris avalanches with limited runout potential. Runout potential of debris flows may increase several fold as their volumes enlarge beyond volcanoes through bulking (entrainment) of sediment. Through this mechanism, the runouts of even relatively small collapses at Cascade Range volcanoes, in the range of 0.1 to 0.2 cubic kilometers, can extend to populated lowlands. (2) Collapse is caused by a variety of triggers: tectonic and volcanic earthquakes, gravitational failure, hydrovolcanism, and

  5. Shallow and Deep-Seated Landslide Differentiation Using Support Vector Machines: A Case Study of the Chuetsu Area, Japan

    Directory of Open Access Journals (Sweden)

    Jie Dou

    2015-01-01

    Full Text Available Landslides are one of the most destructive geological disasters affecting Japan every year, resulting in huge losses in life and property. Numerous susceptibility studies have been conducted to minimize the risk of landslides; however, most of these studies do not differentiate landslide types. This study examines the differences in landslide depth, volume and the risk imposed between shallow and deep-seated landslide types. Shallow and deep-seated landslide prediction is useful in utilizing emergency resources by prioritizing target areas while responding to sediment related disasters. This study utilizes a 2-m DEM derived from airborne Light detection and ranging (Lidar, geological information and support vector machines (SVMs to study the 1225 landslides triggered by the M 6.8 Chuetsu earthquake in Japan and the successive aftershocks. Ten factors, including elevation, slope, aspect, curvature, lithology, distance from the nearest geologic boundary, density of geologic boundaries, distance from drainage network, the compound topographic index (CTI and the stream power index (SPI derived from the DEM and a geological map were analyzed. Iterated over 10 random instances the average training and testing accuracy of landslide type prediction was found to be 89.2 and 77.8%, respectively. We also found that the overall accuracy of SVMs does not rapidly decrease with a decrease in training samples. The trained model was then used to prepare a map showing probable future landslides differentiated into shallow and deep-seated landslides.

  6. Monitoring of Landslide at Tuncbilek Open Pit Stripping Area with Terrestrial Laser Scanner and Optical Images

    Science.gov (United States)

    Ozdogan, Mehmet Volkan; Hamdi Deliormanli, Ahmet

    2016-10-01

    Remote sensing techniques used for providing data on earth sciences have rapidly developed in recent years. Usage of remote sensing for monitoring of slopes have made a lot of progress in the last decade. The most important benefit of remote sensing applications on slope monitoring is safe working conditions with high accurate results. Terrestrial laser scanners are one of the ground-based remote sensing equipment which provide detailed and highly accurate 3D data. In this study terrestrial laser scanner method was carried out for monitoring the landslide at Tuncbilek Open pit stripping area and also optical images were evaluated for determining the development of landslide. The head part of landslide was measured with terrestrial laser scanner at three various dates and the point cloud of head part of landslide were created. Then the three-point cloud were compared. Also six optical satellite image with resolution 1m and below were examined for determining the development of landslide between 2001 and 2013

  7. Landslide tsunami

    Science.gov (United States)

    Ward, Steven N.

    2001-06-01

    In the creation of "surprise tsunami," submarine landslides head the suspect list. Moreover, improving technologies for seafloor mapping continue to sway perceptions on the number and size of surprises that may lie in wait offshore. At best, an entirely new distribution and magnitude of tsunami hazards has yet to be fully appreciated. At worst, landslides may pose serious tsunami hazards to coastlines worldwide, including those regarded as immune. To raise the proper degree of awareness, without needless alarm, the potential and frequency of landslide tsunami have to be assessed quantitatively. This assessment requires gaining a solid understanding of tsunami generation by landslides and undertaking a census of the locations and extent of historical and potential submarine slides. This paper begins the process by offering models of landslide tsunami production, propagation, and shoaling and by exercising the theory on several real and hypothetical landslides offshore Hawaii, Norway, and the United States eastern seaboard. I finish by broaching a line of attack for the hazard assessment by building on previous work that computed probabilistic tsunami hazard from asteroid impacts.

  8. 30 CFR 57.20031 - Blasting underground in hazardous areas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting underground in hazardous areas. 57... MINES Miscellaneous § 57.20031 Blasting underground in hazardous areas. In underground areas where... removed to safe places before blasting....

  9. Geomorphometric analysis of shallow landslides in the Walgau valley (Austria)

    Science.gov (United States)

    Lützenburg, Gregor; Schmaltz, Elmar; Glade, Thomas

    2017-04-01

    Hydrologically triggered shallow landslides are a frequent natural hazard in the Eastern Alps and can cause severe damages to agriculturally used land, houses and infrastructure. Geomorphometric indices allow to estimate the spatial dynamics of shallow landslides based on recurrent landslide inventories. Previous studies found that the morphology of a landslip is closely related to its dominant genetic process. In this study, we focus on the calculation of established geomorphometric indices of the prevailing shallow landslides to assess the spatial landslide distribution in the Walgau valley in Vorarlberg (Austria). Therefore, we compiled a multi-temporal landslide inventory based on eight orthophoto series from 1950 to 2015 and two digital terrain models derived from airborne laser scanning (ALS) data of 2004 and 2011. The 123 mapped landslides and adjacent areas were further distinguished in distinct geomorphic features, such as parent slope, landslide scarp, concave (surface of rupture) and convex (mass material) segments. Lithological settings and anthropogenic impacts such as land use change were also considered in the analysis. A geomorphometric assessment of the mapped landslides, in combination with land cover information yields insights on the spatial dimension of the shallow landslides and the potential fluidity of the materials involved. The geomorphometric analyses revealed that 96 landslides were classified as fluid-flows, 17 landslides were classified as viscous-flows, 8 landslides were classified as slide-flows and 2 landslides were classified as planar slides. Our findings indicate that most of the shallow landslides display a flow-like movement with a rather low material plasticity. This leads to the assumption that the observed landslides in the investigated area might be of low kinetic energy despite their relatively long travel distances. Spatial disparities within the study area were not observable. We conclude that geomorphometric indices are

  10. Landslide databases review in the Geological Surveys of Europe

    Science.gov (United States)

    Herrera, Gerardo

    2017-04-01

    Landslides are one of the most widespread geohazards in Europe, producing significant social and economic damages. Rapid population growth in urban areas throughout many countries in Europe and extreme climatic scenarios can considerably increase landslide risk in the near future. However, many European countries do not include landslide risk into their legislation. Countries lack official methodological assessment guidelines and knowledge about landslide impacts. Although regional and national landslide databases exist in most countries, they are often not integrated because they are owed by different institutions. Hence, a European Landslides Directive, that provides a common legal framework for dealing with landslides, is necessary. With this long-term goal in mind, we present a review of the landslide databases from the Geological Surveys of Europe focusing on their interoperability. The same landslide classification was used for the 849,543 landslide records from the Geological Surveys, from which 36% are slides, 10 % falls, 20% flows, 11% complex slides and 24% remain either unclassified or correspond to another typology. A landslide density map was produced from the available records of the Geological Surveys of 17 countries showing the variable distribution of landslides. There are 0.2 million km2 of landslide prone areas. The comparison of this map with the European landslide susceptibility map ELSUS v1 was successful for 73% of the predictions, and permitted identification of 25% of susceptible areas where landslide records are not available from the Geological Surveys. Taking these results into account the completeness of these landslide databases was evaluated, revealing different landslide hazard management approaches between surveys and countries.

  11. 证据权法在区域滑坡危险性评价中的应用--以贵州省为例%LANDSLIDES HAZARDS ASSESSMENT WITH WEIGHTS OF EVIDENCE---A CASE STUDY IN GUIZHOU,CHINA

    Institute of Scientific and Technical Information of China (English)

    范强; 巨能攀; 向喜琼; 黄健

    2014-01-01

    Landslides are the most common geohazards in mountainous terrains and can cause extraordinary landscape changes and destruction of people’s lives and properties.So assessing landslide hazards is significant and can provide valuable information to planners,developers and engineers.This paper examines some landslides at a hilly area of western China,Guizhou province.The purpose is to generate a landslide susceptibility map using the weights of evidence.It is based on the GIS technology and combined with landslides inventory and environmental factors.The causal factors include lithology,tectonic,elevation,slope,aspect,relief,distance from road and distance from stream.The weight of each causal class is calculated in a GIS software ArcGIS 10.Then the landslide hazard index of each unit is produced and divided into four classes:very high hazard,high hazard,medium hazard and low hazard.Finally,a success rate curve is built to detect the capability rate of the method.The study area under the curve is 0.7 1 .A hazard zonation map is produced and the predictive power of the map is tested on the basis of landslides inventory.The evaluation results are in line with the landslides distribution.The weights of evidence are effective to assess the landslides hazard in regional scale.%以GIS为技术平台,采用证据权法对研究区进行了滑坡地质灾害危险性分析。综合分析历史滑坡数据及其环境因素和触发因素,数据源主要有地形图、DEM、地质图,选取地层岩性、构造、高程、坡度、坡向、地形起伏度、道路、水系作为危险性评价因子。首先应用ArcGIS软件对数据源进行处理,提取各个评价因子图层,并对每个图层进行分级、缓冲区分析等处理,建立若干证据层。然后将历史灾害点与评价因子进行空间关联分析,计算每个评价因子等级的权重,最后计算出评价单元的危险性指数,并将危险性分为极高危险区、高危险

  12. Preliminary Study of Ground Movement in Prone Landslide Area by Means of MAI InSAR A Case Study: Ciloto, West Java, Indonesia

    Science.gov (United States)

    Hayati, Noorlaila; Riedel, Björn; Niemeier, Wolfgang

    2016-04-01

    Ciloto is one of the most prone landslide hazard areas in Indonesia. Several landslides in 2012 and 2013 had been recorded in Ciloto and damaged infrastructure around the area. Investigating the history of ground movement along slope area before the landslide happened could support the hazard mitigation in the future. Considering to an efficient surveying method, space-borne SAR processing is the one appropriate way to monitor the phenomenon in past years. The purpose of this study is detecting ground movement using multi-temporal synthetic aperture radar images. We use 13 ALOS PALSAR images from 2007 to 2009 with combination Fine Beam Single (FBS) and Fine Beam Double (FBD) polarization to investigate the slow movement on slope topography. MAI (Multiple Aperture Interferometry) InSAR method is used to analyze the ground movement from both line-of-sight and along-track direction. We split the synthetic aperture into two-looking aperture so that along-track displacement could be created by the difference of forward-backward looking interferograms. With integration of both methods, we could more precisely detect the movement in prone landslide area and achieve two measurements produced by the same interferogram. However, InSAR requires smaller baseline and good temporal baseline between master and slave images to avoid decorellation. There are only several pairs that meet the condition of proper length and temporal baseline indeed the location is also on the agriculture area where is mostly covered by vegetation. The result for two years observation shows that there is insignificant slow movement along slope surface in Ciloto with -2 - -7 cm in range looks or line of sight and 9-40 cm in along track direction. Based on geometry SAR , the most visible detecting of displacement is on the north-west area due to utilization of ascending SAR images.

  13. Scenario earthquake hazards for the Long Valley Caldera-Mono Lake area, east-central California

    Science.gov (United States)

    Chen, Rui; Branum, David M.; Wills, Chris J.; Hill, David P.

    2014-01-01

    As part of the U.S. Geological Survey’s (USGS) multi-hazards project in the Long Valley Caldera-Mono Lake area, the California Geological Survey (CGS) developed several earthquake scenarios and evaluated potential seismic hazards, including ground shaking, surface fault rupture, liquefaction, and landslide hazards associated with these earthquake scenarios. The results of these analyses can be useful in estimating the extent of potential damage and economic losses because of potential earthquakes and in preparing emergency response plans. The Long Valley Caldera-Mono Lake area has numerous active faults. Five of these faults or fault zones are considered capable of producing magnitude ≥6.7 earthquakes according to the Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2) developed by the 2007 Working Group of California Earthquake Probabilities (WGCEP) and the USGS National Seismic Hazard Mapping (NSHM) Program. These five faults are the Fish Slough, Hartley Springs, Hilton Creek, Mono Lake, and Round Valley Faults. CGS developed earthquake scenarios for these five faults in the study area and for the White Mountains Fault to the east of the study area. Earthquake scenarios are intended to depict the potential consequences of significant earthquakes. They are not necessarily the largest or most damaging earthquakes possible. Earthquake scenarios are both large enough and likely enough that emergency planners should consider them in regional emergency response plans. Earthquake scenarios presented here are based on fault geometry and activity data developed by the WGCEP, and are consistent with the 2008 Update of the United States National Seismic Hazard Maps (NSHM).For the Hilton Creek Fault, two alternative scenarios were developed in addition to the NSHM scenario to account for different opinions in how far north the fault extends into the Long Valley Caldera. For each scenario, ground motions were calculated using the current standard practice

  14. An Overview of Landslide Forecasting Using Wireless Sensor Network and Geographical Information System

    Directory of Open Access Journals (Sweden)

    Anitha K

    2016-04-01

    Full Text Available Landslides are natural disasters cause losses in many human lives and damage properties every year around the globe. Using of physical and electronic monitoring makes possible in prediction and prevention losses from landslide. Today, the wireless sensor network technology has been developed rapidly for landslide predictions. The primary object of this present paper is to overview the landslide prediction method using wireless sensor networks (WSN and geographical information systems (GIS. The paper focuses on various landslide conditioning factors, WSN design requirement, and small scale down slope model similar to study area (hazard location. Landslide prediction database to support warning system are also discussed

  15. Landslides susceptibility change over time according to terrain conditions in a mountain area of the tropic region.

    Science.gov (United States)

    Pineda, M C; Viloria, J; Martínez-Casasnovas, J A

    2016-04-01

    Susceptibility to landslides in mountain areas results from the interaction of various factors related to relief formation and soil development. The assessment of landslide susceptibility has generally taken into account individual events, or it has been aimed at establishing relationships between landslide-inventory maps and maps of environmental factors, without considering that such relationships can change in space and time. In this work, temporal and space changes in landslides were analysed in six different combinations of date and geomorphological conditions, including two different geological units, in a mountainous area in the north-centre of Venezuela, in northern South America. Landslide inventories from different years were compared with a number of environmental factors by means of logistic regression analysis. The resulting equations predicted landslide susceptibility from a range of geomorphometric parameters and a vegetation index, with diverse accuracy, in the study area. The variation of the obtained models and their prediction accuracy between geological units and dates suggests that the complexity of the landslide processes and their explanatory factors changed over space and time in the studied area. This calls into question the use of a single model to evaluate landslide susceptibility over large regions.

  16. Compounding Hazards Facing Nepalese Villages due to Glacial Lake Thulagi, Extreme Monsoons, and Landslides

    Science.gov (United States)

    Leonard, Gregory; Kargel, Jeffrey; Regmi, Dhananjay

    2014-05-01

    Thulagi Tsho is listed by ICIMOD as among the most hazardous glacial lakes in Nepal. The listing is warranted by the physiography and downstream vulnerabilities. Tal Village—along a major trekking route—and a hydroelectric dam and reservoir are notably at risk due to the potential for a glacier lake outburst flood (GLOF), an extreme summer monsoon, extreme spring snowmelt, landslides, and rockfalls. Tal is downstream from Thulagi Lake just a couple meters above river level, and ordinary monsoons already cause an approach toward flood conditions, according to residents. A high flood stage due to an extreme monsoon or unusually rapid springtime melting of a thick winter snowpack could be catastrophic. Two significant mass movements occurred recently in Tal, one having buried some structures in the village in June 2012. In a favorable note, satellite image analysis shows that Thulagi Lake has slowed its elongation in the last couple years. Furthermore, any tsunami or other flood surge would have to traverse and erode a wide end moraine in order to generate a GLOF. On the other hand, remote sensing and field observations show that wasting of Thulagi Glacier has debuttressed the northern lateral moraine, which is slipping toward the growing lake and the thinning/retreating glacier. The landslip itself is not necessarily a bad thing: it is causing a loss of gravitational potential energy of the lateral moraine, and if that process continues gradually, it will result in diminished instability. However, the debuttressing and moraine slip signifies that the moraines are unstable. Will a rapid mass movement dump into the lake? Triggers could include seismicity, extreme rainfall, or a small landslip. The risk of a serious GLOF exceeds that of Imja Lake due to Thulagi Lake's large hydrographic head and the shape of its downstream end, which could funnel and amplify a potential tsunami generated by a large mass movement into the lake. A moraine collapse into the lake would

  17. Assessment of landslide hazards resulting from the February 13, 2001, El Salvador earthquake; a report to the government of El Salvador and the U. S. Agency for International Development

    Science.gov (United States)

    Baum, Rex L.; Crone, Anthony J.; Escobar, Demetreo; Harp, Edwin L.; Major, Jon J.; Martinez, Mauricio; Pullinger, Carlos; Smith, Mark E.

    2001-01-01

    On February 13, 2001, a magnitude 6.5 earthquake occurred about 40 km eastsoutheast of the capital city of San Salvador in central El Salvador and triggered thousands of landslides in the area east of Lago de Ilopango. The landslides are concentrated in a 2,500-km2 area and are particularly abundant in areas underlain by thick deposits of poorly consolidated, late Pleistocene and Holocene Tierra Blanca rhyolitic tephras that were erupted from Ilopango caldera. Drainages in the tephra deposits are deeply incised, and steep valley walls failed during the strong shaking. Many drainages are clogged with landslide debris that locally buries the adjacent valley floor. The fine grain-size of the tephra facilitates its easy mobilization by rainfall runoff. The potential for remobilizing the landslide debris as debris flows and in floods is significant as this sediment is transported through the drainage systems during the upcoming rainy season. In addition to thousands of shallow failures, two very large landslides occurred that blocked the Rio El Desague and the Rio Jiboa. The Rio El Desague landslide has an estimated volume of 1.5 million m3, and the Rio Jiboa landslide has an estimated volume of 12 million m3. Field studies indicate that catastrophic draining of the Rio El Desague landslide-dammed lake would pose a minimal flooding hazard, whereas catastrophic draining of the Rio Jiboa lake would pose a serious hazard and warrants immediate action. Construction of a spillway across part of the dam could moderate the impact of catastrophic lake draining and the associated flood. Two major slope failures on the northern side of Volcan San Vicente occurred in the upper reaches of Quebrada Del Muerto and the Quebrada El Blanco. The landslide debris in the Quebrada Del Muerto consists dominantly of blocks of well-lithified andesite, whereas the debris in the Quebrada El Blanco consists of poorly consolidated pyroclastic sediment. The large blocks of lithified rock in

  18. DEBRIS FLOW AND LANDSLIDE HAZARDS UNDER CERTAIN TYPES OF ATMOSPHERIC CIRCULATION

    Directory of Open Access Journals (Sweden)

    Nina Kononova

    2012-01-01

    Full Text Available Conditions of formation and development of landslides and debris flows in the Black Sea coast of the Caucasus and on Sakhalin Island were considered. They are formed under the influence of heavy rainfall under the influence of the Mediterranean cyclones outlet in the Black Sea coast of the Caucasus and of the Pacific cyclones outlet on Sakhalin Island in the same macro-circulation processes. Activity of landslides and debris flows in these regions has been shown to be connected with certain types of atmospheric circulation during the XX—the beginning of the XXI century. Based on these results, possible increase in the activity of landslides and debris flows, in the Black Sea coast of the Caucasus and Sakhalin Island, is suggested.

  19. Understanding earthquake hazards in urban areas - Evansville Area Earthquake Hazards Mapping Project

    Science.gov (United States)

    Boyd, Oliver S.

    2012-01-01

    The region surrounding Evansville, Indiana, has experienced minor damage from earthquakes several times in the past 200 years. Because of this history and the proximity of Evansville to the Wabash Valley and New Madrid seismic zones, there is concern among nearby communities about hazards from earthquakes. Earthquakes currently cannot be predicted, but scientists can estimate how strongly the ground is likely to shake as a result of an earthquake and are able to design structures to withstand this estimated ground shaking. Earthquake-hazard maps provide one way of conveying such information and can help the region of Evansville prepare for future earthquakes and reduce earthquake-caused loss of life and financial and structural loss. The Evansville Area Earthquake Hazards Mapping Project (EAEHMP) has produced three types of hazard maps for the Evansville area: (1) probabilistic seismic-hazard maps show the ground motion that is expected to be exceeded with a given probability within a given period of time; (2) scenario ground-shaking maps show the expected shaking from two specific scenario earthquakes; (3) liquefaction-potential maps show how likely the strong ground shaking from the scenario earthquakes is to produce liquefaction. These maps complement the U.S. Geological Survey's National Seismic Hazard Maps but are more detailed regionally and take into account surficial geology, soil thickness, and soil stiffness; these elements greatly affect ground shaking.

  20. A logical framework for ranking landslide inventory maps

    Science.gov (United States)

    Santangelo, Michele; Fiorucci, Federica; Bucci, Francesco; Cardinali, Mauro; Ardizzone, Francesca; Marchesini, Ivan; Cesare Mondini, Alessandro; Reichenbach, Paola; Rossi, Mauro; Guzzetti, Fausto

    2014-05-01

    Landslides inventory maps are essential for quantitative landslide hazard and risk assessments, and for geomorphological and ecological studies. Landslide maps, including geomorphological, event based, multi-temporal, and seasonal inventory maps, are most commonly prepared through the visual interpretation of (i) monoscopic and stereoscopic aerial photographs, (ii) satellite images, (iii) LiDAR derived images, aided by more or less extensive field surveys. Landslide inventory maps are the basic information for a number of different scientific, technical and civil protection purposes, such as: (i) quantitative geomorphic analyses, (ii) erosion studies, (iii) deriving landslide statistics, (iv) urban development planning (v) landslide susceptibility, hazard and risk evaluation, and (vi) landslide monitoring systems. Despite several decades of activity in landslide inventory making, still no worldwide-accepted standards, best practices and protocols exist for the ranking and the production of landslide inventory maps. Standards for the preparation (and/or ranking) of landslide inventories should indicate the minimum amount of information for a landslide inventory map, given the scale, the type of images, the instrumentation available, and the available ancillary data. We recently attempted at a systematic description and evaluation of a total of 22 geomorphological inventories, 6 multi-temporal inventories, 10 event inventories, and 3 seasonal inventories, in the scale range between 1:10,000 and 1:500,000, prepared for areas in different geological and geomorphological settings. All of the analysed inventories were carried out by using image interpretation techniques, or field surveys. Firstly, a detailed characterisation was performed for each landslide inventory, mainly collecting metadata related (i) to the amount of information used for preparing the landslide inventory (i.e. images used, instrumentation, ancillary data, digitalisation method, legend, validation

  1. Landslide inventory development in a data sparse region: spatial and temporal characteristics of landslides in Papua New Guinea

    Directory of Open Access Journals (Sweden)

    J. C. Robbins

    2015-08-01

    Full Text Available In Papua New Guinea (PNG earthquakes and rainfall events form the dominant trigger mechanisms capable of generating many landslides. Large volume and high density landsliding can result in significant socio-economic impacts, which are felt particularly strongly in the largely subsistence-orientated communities which reside in the most susceptible areas of the country. As PNG has undergone rapid development and increased external investment from mining and other companies, population and settled areas have increased, hence the potential for damage from landslides has also increased. Information on the spatial and temporal distribution of landslides, at a regional-scale, is critical for developing landslide hazard maps and for planning, sustainable development and decision making. This study describes the methods used to produce the first, country-wide landslide inventory for PNG and analyses of landslide events which occurred between 1970 and 2013. The findings illustrate that there is a strong climatic control on landslide-triggering events and that the majority (~ 61 % of landslides in the PNG landslide inventory are initiated by rainfall related triggers. There is also large year to year variability in the annual occurrence of landslide events and this is related to the phase of El Niño Southern Oscillation (ENSO and mesoscale rainfall variability. Landslide-triggering events occur during the north-westerly monsoon season during all phases of ENSO, but less landslide-triggering events are observed during drier season months (May to October during El Niño phases, than either La Niña or ENSO neutral periods. This analysis has identified landslide hazard hotspots and relationships between landslide occurrence and rainfall climatology and this information can prove to be very valuable in the assessment of trends and future behaviour, which can be useful for policy makers and planners.

  2. Landslide inventory development in a data sparse region: spatial and temporal characteristics of landslides in Papua New Guinea

    Science.gov (United States)

    Robbins, J. C.; Petterson, M. G.

    2015-08-01

    In Papua New Guinea (PNG) earthquakes and rainfall events form the dominant trigger mechanisms capable of generating many landslides. Large volume and high density landsliding can result in significant socio-economic impacts, which are felt particularly strongly in the largely subsistence-orientated communities which reside in the most susceptible areas of the country. As PNG has undergone rapid development and increased external investment from mining and other companies, population and settled areas have increased, hence the potential for damage from landslides has also increased. Information on the spatial and temporal distribution of landslides, at a regional-scale, is critical for developing landslide hazard maps and for planning, sustainable development and decision making. This study describes the methods used to produce the first, country-wide landslide inventory for PNG and analyses of landslide events which occurred between 1970 and 2013. The findings illustrate that there is a strong climatic control on landslide-triggering events and that the majority (~ 61 %) of landslides in the PNG landslide inventory are initiated by rainfall related triggers. There is also large year to year variability in the annual occurrence of landslide events and this is related to the phase of El Niño Southern Oscillation (ENSO) and mesoscale rainfall variability. Landslide-triggering events occur during the north-westerly monsoon season during all phases of ENSO, but less landslide-triggering events are observed during drier season months (May to October) during El Niño phases, than either La Niña or ENSO neutral periods. This analysis has identified landslide hazard hotspots and relationships between landslide occurrence and rainfall climatology and this information can prove to be very valuable in the assessment of trends and future behaviour, which can be useful for policy makers and planners.

  3. Colluvium supply in humid regions limits the frequency of storm-triggered landslides.

    Science.gov (United States)

    Parker, Robert N; Hales, Tristram C; Mudd, Simon M; Grieve, Stuart W D; Constantine, José A

    2016-09-30

    Shallow landslides, triggered by extreme rainfall, are a significant hazard in mountainous landscapes. The hazard posed by shallow landslides depends on the availability and strength of colluvial material in landslide source areas and the frequency and intensity of extreme rainfall events. Here we investigate how the time taken to accumulate colluvium affects landslide triggering rate in the Southern Appalachian Mountains, USA and how this may affect future landslide hazards. We calculated the failure potential of 283 hollows by comparing colluvium depths to the minimum (critical) soil depth required for landslide initiation in each hollow. Our data show that most hollow soil depths are close to their critical depth, with 62% of hollows having soils that are too thin to fail. Our results, supported by numerical modeling, reveal that landslide frequency in many humid landscapes may be insensitive to projected changes in the frequency of intense rainfall events.

  4. Estimating return period of landslide triggering by Monte Carlo simulation

    Science.gov (United States)

    Peres, D. J.; Cancelliere, A.

    2016-10-01

    Assessment of landslide hazard is a crucial step for landslide mitigation planning. Estimation of the return period of slope instability represents a quantitative method to map landslide triggering hazard on a catchment. The most common approach to estimate return periods consists in coupling a triggering threshold equation, derived from an hydrological and slope stability process-based model, with a rainfall intensity-duration-frequency (IDF) curve. Such a traditional approach generally neglects the effect of rainfall intensity variability within events, as well as the variability of initial conditions, which depend on antecedent rainfall. We propose a Monte Carlo approach for estimating the return period of shallow landslide triggering which enables to account for both variabilities. Synthetic hourly rainfall-landslide data generated by Monte Carlo simulations are analysed to compute return periods as the mean interarrival time of a factor of safety less than one. Applications are first conducted to map landslide triggering hazard in the Loco catchment, located in highly landslide-prone area of the Peloritani Mountains, Sicily, Italy. Then a set of additional simulations are performed in order to evaluate the traditional IDF-based method by comparison with the Monte Carlo one. Results show that return period is affected significantly by variability of both rainfall intensity within events and of initial conditions, and that the traditional IDF-based approach may lead to an overestimation of the return period of landslide triggering, or, in other words, a non-conservative assessment of landslide hazard.

  5. Extreme Precipitation and High-Impact Landslides

    Science.gov (United States)

    Kirschbaum, Dalia; Adler, Robert; Huffman, George; Peters-Lidard, Christa

    2012-01-01

    It is well known that extreme or prolonged rainfall is the dominant trigger of landslides; however, there remain large uncertainties in characterizing the distribution of these hazards and meteorological triggers at the global scale. Researchers have evaluated the spatiotemporal distribution of extreme rainfall and landslides at local and regional scale primarily using in situ data, yet few studies have mapped rainfall-triggered landslide distribution globally due to the dearth of landslide data and consistent precipitation information. This research uses a newly developed Global Landslide Catalog (GLC) and a 13-year satellite-based precipitation record from Tropical Rainfall Measuring Mission (TRMM) data. For the first time, these two unique products provide the foundation to quantitatively evaluate the co-occurence of precipitation and rainfall-triggered landslides globally. The GLC, available from 2007 to the present, contains information on reported rainfall-triggered landslide events around the world using online media reports, disaster databases, etc. When evaluating this database, we observed that 2010 had a large number of high-impact landslide events relative to previous years. This study considers how variations in extreme and prolonged satellite-based rainfall are related to the distribution of landslides over the same time scales for three active landslide areas: Central America, the Himalayan Arc, and central-eastern China. Several test statistics confirm that TRMM rainfall generally scales with the observed increase in landslide reports and fatal events for 2010 and previous years over each region. These findings suggest that the co-occurrence of satellite precipitation and landslide reports may serve as a valuable indicator for characterizing the spatiotemporal distribution of landslide-prone areas in order to establish a global rainfall-triggered landslide climatology. This research also considers the sources for this extreme rainfall, citing

  6. GIS and ANN model for landslide susceptibility mapping

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Landslide hazard is as the probability of occurrence of apotentially damaging landslide phenomenon within specified period of time and within a given area. The susceptibility map provides the relative spatial probability of landslides occurrence. A study is presented of the application of GIS and artificial neural network model to landslide susceptibility mapping, with particular reference to landslides on natural terrain in this paper. The method has been applied to Lantau Island, the largest outlying island within the territory of Hong Kong. A three-level neural network model was constructed and trained by the back-propagate algorithm in the geographical database of the study area. The data in the database includes digital elevation modal and its derivatives, landslides distribution and their attributes, superficial geological maps, vegetation cover, the raingauges distribution and their 14 years 5-minute observation. Based on field inspection and analysis of correlation between terrain variables and landslides frequency, lithology, vegetation cover, slope radient, slope aspect, slope curvature, elevation, the characteristic value, the rainstorms corresponding to the landslide, and distance to drainage line are considered to be related to landslide usceptibility in this study. The artificial neural network is then coupled with the ArcView3.2 GIS software to produce the landslide susceptibility map, which classifies the susceptibility into three levels: low, moderate, and high. The results from this study indicate that GIS coupled with artificial nural network model is a flexible and powerful approach to identify the spatial probability of hazards.

  7. Designing Cognitive Intervention to Improve the Awareness Index of the Residents in the Landslide Area

    Science.gov (United States)

    Susanto, N.; Putranto, T. T.; Ulfa, E. A.

    2017-02-01

    Considering Semarang as a city with a high potential of landslides occurrences in its almost area, human as the part of the system should be played as a centre of the disaster management system to reduce the natural disaster risk. The study area is located in Manyaran district (the west of Semarang) which is categorised as a vulnerable of landslide area. This study aims at establishing a cognitive intervention based on a cause analysis (Fault Tree Analysis/FTA) to find the cause of low value and improve the awareness index of residents as the implementation of human-based disaster management model. The FTA result was then combined with the demographical data to generate the design of the cognitive intervention. The FTA result conducted that the preparedness of emergency planning had the lowest value (18.2%) which was caused by the lack individual preparation including lack of residents knowledge, and the absence of observation facilities as well as the lack of evacuation planning. Analysis of demographical data resulted in a situation of lack socialisation and knowledge of the residents regarding the landslide occurrence. The model of cognitive intervention then utilised some tools such as video, module and discussion to improve the awareness index.

  8. Landslide databases for applied landslide impact research: the example of the landslide database for the Federal Republic of Germany

    Science.gov (United States)

    Damm, Bodo; Klose, Martin

    2014-05-01

    This contribution presents an initiative to develop a national landslide database for the Federal Republic of Germany. It highlights structure and contents of the landslide database and outlines its major data sources and the strategy of information retrieval. Furthermore, the contribution exemplifies the database potentials in applied landslide impact research, including statistics of landslide damage, repair, and mitigation. The landslide database offers due to systematic regional data compilation a differentiated data pool of more than 5,000 data sets and over 13,000 single data files. It dates back to 1137 AD and covers landslide sites throughout Germany. In seven main data blocks, the landslide database stores besides information on landslide types, dimensions, and processes, additional data on soil and bedrock properties, geomorphometry, and climatic or other major triggering events. A peculiarity of this landslide database is its storage of data sets on land use effects, damage impacts, hazard mitigation, and landslide costs. Compilation of landslide data is based on a two-tier strategy of data collection. The first step of information retrieval includes systematic web content mining and exploration of online archives of emergency agencies, fire and police departments, and news organizations. Using web and RSS feeds and soon also a focused web crawler, this enables effective nationwide data collection for recent landslides. On the basis of this information, in-depth data mining is performed to deepen and diversify the data pool in key landslide areas. This enables to gather detailed landslide information from, amongst others, agency records, geotechnical reports, climate statistics, maps, and satellite imagery. Landslide data is extracted from these information sources using a mix of methods, including statistical techniques, imagery analysis, and qualitative text interpretation. The landslide database is currently migrated to a spatial database system

  9. Deviation from Power Law Behavior in Landslide Phenomenon

    Science.gov (United States)

    Li, L.; Lan, H.; Wu, Y.

    2013-12-01

    Power law distribution of magnitude is widely observed in many natural hazards (e.g., earthquake, floods, tornadoes, and forest fires). Landslide is unique as the size distribution of landslide is characterized by a power law decrease with a rollover in the small size end. Yet, the emergence of the rollover, i.e., the deviation from power law behavior for small size landslides, remains a mystery. In this contribution, we grouped the forces applied on landslide bodies into two categories: 1) the forces proportional to the volume of failure mass (gravity and friction), and 2) the forces proportional to the area of failure surface (cohesion). Failure occurs when the forces proportional to volume exceed the forces proportional to surface area. As such, given a certain mechanical configuration, the failure volume to failure surface area ratio must exceed a corresponding threshold to guarantee a failure. Assuming all landslides share a uniform shape, which means the volume to surface area ratio of landslide regularly increase with the landslide volume, a cutoff of landslide volume distribution in the small size end can be defined. However, in realistic landslide phenomena, where heterogeneities of landslide shape and mechanical configuration are existent, a simple cutoff of landslide volume distribution does not exist. The stochasticity of landslide shape introduce a probability distribution of the volume to surface area ratio with regard to landslide volume, with which the probability that the volume to surface ratio exceed the threshold can be estimated regarding values of landslide volume. An experiment based on empirical data showed that this probability can induce the power law distribution of landslide volume roll down in the small size end. We therefore proposed that the constraints on the failure volume to failure surface area ratio together with the heterogeneity of landslide geometry and mechanical configuration attribute for the deviation from power law

  10. Relationship between landslides and lithology in the Three Gorges Reservoir area based on GIS and information value model

    Institute of Scientific and Technical Information of China (English)

    Caiyan WU; Jianping QIAO

    2009-01-01

    Development of landslides in the Three Gorges Reservoir area is related to many factors. Lithology is one of the indispensable internal factors, besides relative height differences, slope gradients and slope profiles. We used an information value model with geographical information system (GIS) technology to study how lithology contributes to the development of landslides from the Yunyang to Wushan segment in the Three Gorges Reservoir area and we quantify the relationship between lithology and development of landslides. Via an investigation of 205 examples of past landslides, we found that the lithology of J3s, J3p and T2b contributes most. Our research results can provide a valid basis for future construction in the Three Gorges Reservoir area.

  11. Map showing recent and historic landslide activity on coastal bluffs of Puget Sound between Shilshole Bay and Everett, Washington

    Science.gov (United States)

    Baum, R.L.; Harp, E.L.; Hultman, W.A.

    2000-01-01

    Many landslides occurred on the coastal bluffs between Seattle and Everett, Washington during the winters of 1996 and 1997. Shallow earth slides and debris flows were the most common, but a few deep-seated rotational earth slides also occurred. The landslides caused significant property damage and interfered with rail traffic; future landslides in the area pose significant hazards to property and public safety. Field observations indicate that ground-water seepage, runoff concentration, and dumping at the tops of the bluffs all contributed to instability of the bluffs. Most landslides in the study area occurred in colluvium, residuum, and landslide deposits derived from the Vashon Drift, particularly the advance outwash. In the northern part of the area, colluvium derived from the Pleistocene Whidbey Formation was also involved in shallow landslides. Comparison of recent activity with historic records in the southern part of the map area indicates that landslides tend to occur in many of the same areas as previous landslides.

  12. Satellite image collection modeling for large area hazard emergency response

    Science.gov (United States)

    Liu, Shufan; Hodgson, Michael E.

    2016-08-01

    Timely collection of critical hazard information is the key to intelligent and effective hazard emergency response decisions. Satellite remote sensing imagery provides an effective way to collect critical information. Natural hazards, however, often have large impact areas - larger than a single satellite scene. Additionally, the hazard impact area may be discontinuous, particularly in flooding or tornado hazard events. In this paper, a spatial optimization model is proposed to solve the large area satellite image acquisition planning problem in the context of hazard emergency response. In the model, a large hazard impact area is represented as multiple polygons and image collection priorities for different portion of impact area are addressed. The optimization problem is solved with an exact algorithm. Application results demonstrate that the proposed method can address the satellite image acquisition planning problem. A spatial decision support system supporting the optimization model was developed. Several examples of image acquisition problems are used to demonstrate the complexity of the problem and derive optimized solutions.

  13. Landslide inventory maps: New tools for an old problem

    Science.gov (United States)

    Guzzetti, Fausto; Mondini, Alessandro Cesare; Cardinali, Mauro; Fiorucci, Federica; Santangelo, Michele; Chang, Kang-Tsung

    2012-04-01

    Landslides are present in all continents, and play an important role in the evolution of landscapes. They also represent a serious hazard in many areas of the world. Despite their importance, we estimate that landslide maps cover less than 1% of the slopes in the landmasses, and systematic information on the type, abundance, and distribution of landslides is lacking. Preparing landslide maps is important to document the extent of landslide phenomena in a region, to investigate the distribution, types, pattern, recurrence and statistics of slope failures, to determine landslide susceptibility, hazard, vulnerability and risk, and to study the evolution of landscapes dominated by mass-wasting processes. Conventional methods for the production of landslide maps rely chiefly on the visual interpretation of stereoscopic aerial photography, aided by field surveys. These methods are time consuming and resource intensive. New and emerging techniques based on satellite, airborne, and terrestrial remote sensing technologies, promise to facilitate the production of landslide maps, reducing the time and resources required for their compilation and systematic update. In this work, we first outline the principles for landslide mapping, and we review the conventional methods for the preparation of landslide maps, including geomorphological, event, seasonal, and multi-temporal inventories. Next, we examine recent and new technologies for landslide mapping, considering (i) the exploitation of very-high resolution digital elevation models to analyze surface morphology, (ii) the visual interpretation and semi-automatic analysis of different types of satellite images, including panchromatic, multispectral, and synthetic aperture radar images, and (iii) tools that facilitate landslide field mapping. Next, we discuss the advantages and the limitations of the new remote sensing data and technology for the production of geomorphological, event, seasonal, and multi-temporal inventory maps

  14. Land Cover Mapping using GEOBIA to Estimate Loss of Salacca zalacca Trees in Landslide Area of Clapar, Madukara District of Banjarnegara

    Science.gov (United States)

    Permata, Anggi; Juniansah, Anwar; Nurcahyati, Eka; Dimas Afrizal, Mousafi; Adnan Shafry Untoro, Muhammad; Arifatha, Na'ima; Ramadhani Yudha Adiwijaya, Raden; Farda, Nur Mohammad

    2016-11-01

    Landslide is an unpredictable natural disaster which commonly happens in highslope area. Aerial photography in small format is one of acquisition method that can reach and obtain high resolution spatial data faster than other methods, and provide data such as orthomosaic and Digital Surface Model (DSM). The study area contained landslide area in Clapar, Madukara District of Banjarnegara. Aerial photographs of landslide area provided advantage in objects visibility. Object's characters such as shape, size, and texture were clearly seen, therefore GEOBIA (Geography Object Based Image Analysis) was compatible as method for classifying land cover in study area. Dissimilar with PPA (PerPixel Analyst) method that used spectral information as base object detection, GEOBIA could use spatial elements as classification basis to establish a land cover map with better accuracy. GEOBIA method used classification hierarchy to divide post disaster land cover into three main objects: vegetation, landslide/soil, and building. Those three were required to obtain more detailed information that can be used in estimating loss caused by landslide and establishing land cover map in landslide area. Estimating loss in landslide area related to damage in Salak (Salacca zalacca) plantations. This estimation towards quantity of Salak tree that were drifted away by landslide was calculated in assumption that every tree damaged by landslide had same age and production class with other tree that weren't damaged. Loss calculation was done by approximating quantity of damaged trees in landslide area with data of trees around area that were acquired from GEOBIA classification method.

  15. LANDSLIDE HAZARD ZONATION AND APPLICATION OF GIS%滑坡灾害空间区划及GIS应用研究

    Institute of Scientific and Technical Information of China (English)

    殷坤龙; 朱良峰

    2001-01-01

    Landslide hazard zonation is one of the main considerations in the field of landslide research in the world. Random reflects one aspect of landslide generation, but regional regularities and repetition of individual landslide phenomenon dominate the distribution of landslides on a regional scale. It is of not only theoretical significance but also practical importance to study spatial hazard zonation in the propose of hazard reduction and land planning. This paper theoretically discusses the fundamentals of landslide hazard zonation, definition of terms used in risk assessment, and mapping network by GIS. Based on the platform of software MAPGIS and further development, Information Analysis System of Landslide Hazard (IASLH) has been developed to illustrate hazard zonation in Han River valley which was heavily threatened.%滑坡灾害空间区划研究是当前国内外滑坡领域的重要研究方向之一。虽然滑坡灾害的发生具有随机性的特点,但其发生的区域性和重复性特点则是区域滑坡分布与发生的总体规律。从减灾与土地规划的角度,开展滑坡灾害空间区划研究具有十分重要的理论和实际意义。文中重点探讨了滑坡灾害空间区划的理论体系、灾害风险评估的基本术语定义及GIS制图的基本原理,采用MAPGIS软件为平台及其二次开发的滑坡灾害信息分析系统,在中国滑坡重灾害的汉江流域开展了灾害危险性空间区划应用研究。

  16. GIS-supported geomorphological landslide hazard analysis in the Lainbach catchment, Upper Bavaria

    Science.gov (United States)

    Trau, J.; Ergenzinger, P.

    2003-04-01

    The Lainbach basin is located at the fringe of the Northern Limestone Alps. Predominant mass movements such as translational and rotational slides as well as debris flows are mainly linked to glacial deposits (Pleistocene valley fill) and Flysch series covering approximately 50% of the basin. The pre-Pleistocene relief is buried to a maximum thickness of 170 m of till, glacio-limnic and glacio-fluvial sediments. The spatial and temporal distributions of mass movements are coupled with different stages of fluvial incision. Recent fluvial processes are mainly bedrock controlled in the lower reaches. A special geomorphological map at a scale of 1:10.000 illustrates the relief evolution. In addition, the map focuses on past and recent process-forms related to mass movements. Thus areas of active and inactive mass movements can be easily distinguished. Zones of activity and the hazard potential can be deduced from the map. Hazard assessment is supported by GIS modelling, DEM analysis, multi-temporal time series analysis and aerial photo interpretation. Geophysical soundings are important for detailed site specific information such as shear planes and sediment thickness. A GIS model based on the parameters geology, topography (slope angle, curvature), thickness of loosely-consolidated material, vegetation and hydrology (proximity to receiving stream) was developed. Calculation of failure rates allow a specific value to be assigned to each parameter class indicating its role in the mass movement process. About 90% of the mapped mass movements were correctly classified by the model. Although the overall match seems to be quite good there are some localities where the modelled and the mapped results differ significantly. In the future, the mapped results should be considered together with further “expert knowledge” for an improvement of the GIS model.

  17. Age distribution of fossil landslides in the Tyrol (Austria and its surrounding areas

    Directory of Open Access Journals (Sweden)

    C. Prager

    2008-04-01

    Full Text Available Some of the largest mass movements in the Alps cluster spatially in the Tyrol (Austria. Fault-related valley deepening and coalescence of brittle discontinuities structurally controlled the progressive failure and the kinematics of several slopes. To evaluate the spatial and temporal landslide distribution, a first comprehensive compilation of dated mass movements in the Eastern Alps has been made. At present, more than 480 different landslides in the Tyrol and its surrounding areas, including some 120 fossil events, are recorded in a GIS-linked geodatabase. These compiled data show a rather continuous temporal distribution of landslide activities, with (i some peaks of activity in the early Holocene at about 10 500–9400 cal BP and (ii in the Tyrol a significant increase of deep-seated rockslides in the Subboreal at about 4200–3000 cal BP. The majority of Holocene mass movements were not directly triggered by deglaciation processes, but clearly took a preparation of some 1000 years, after ice withdrawal, until slopes collapsed. In view of this, several processes that may promote rock strength degradation are discussed. After the Late-Glacial, slope stabilities were affected by stress redistribution and by subcritical crack growth. Fracture propagating processes may have been favoured by glacial loading and unloading, by earthquakes and by pore pressure fluctuations. Repeated dynamic loading, even if at subcritical energy levels, initiates brittle fracture propagation and thus substantially promotes slope instabilities. Compiled age dating shows that several landslides in the Tyrol coincide temporally with the progradation of some larger debris flows in the nearby main valleys and, partially, with glacier advances in the Austrian Central Alps, indicating climatic phases of increased water supply. This gives evidence of elevated pore pressures within the intensely fractured rock masses. As a result, deep-seated gravitational slope deformations

  18. The Tagus River delta (off Lisbon, Portugal) as a repository of landslides. Implications on trigger mechanisms, tsunami hazard and neotectonics

    Science.gov (United States)

    Terrinha, Pedro; Duarte, Henrique; Noiva, João; Ribeiro, Carlos; Brito, Pedro; Baptista, Maria Ana; Miranda, Miguel; Omira, Rachid; Magalhães, Vitor; Roque, Cristina

    2015-04-01

    The seismic stratigraphy of the Tagus estuary ebb-tidal delta of Lisbon (Portugal) is investigated with the purpose of searching for evidences of possible sedimentary or erosive features associated with landslides or mass wasting deposits (MTD) events. A special attention was given to events that could have been triggered by large earthquakes that are known to have struck the West of Portugal and Spain in historical and pre-historical times. These earthquakes destroyed Lisbon at least twice in the last 500 years, being the 1755 Lisbon earthquake of estimated magnitude >8.5. To investigate these geological features the seismic reflection dataset used in this work consists of Chirp (Lisboa98 dataset), Sparker single channel (PACEMAKER 2011 dataset) and multichannel seismic (MCS) data (TAGUSDELTA 2013 dataset). Cross-lines of MCS data were acquired crossing the core sampling sites done in previous works. Calibration of the seismic lines width the core data led to infer that the Tagus ebb delta started its formation around 17ky BP and it consists of two main stratigraphic units, the younger of which initiated its formation at approximately 13ky BP. The lower deltaic unit contains several MTDs and/or landslides that could not be mapped with the present dataset. In the upper unit we report the existence of a landslide with 10km of length, 4.5km of width and 20m of maximum thickness that accounted for the collapse of half of the Tagus river delta front. The internal structure of the landslide varies laterally. The main different aspects are, as follows, i) the landslide can be dismembered along slope due to stretching parallel associated to differential movement along slope, ii) it can show internal discontinuities that represent mechanical detachments that separate imbricate wedges and iii) distal deposited bodies completely detached from the main landslide body. The age of the landslide is discussed; an estimated age of >8ky BP is proposed by stratigraphic correlation

  19. Spatial prediction of landslide for Badong County in the Three Gorges reservoir district

    Institute of Scientific and Technical Information of China (English)

    Huiming TANG; Yiping WU

    2006-01-01

    By using the landslide risk evaluating model and the advantages of GIS technology in image processing and space analysis, the relative landslide hazard and risk evaluating system of the new county site of Badong is built up. The system is mainly consisted of four subsystems: Information management subsystem, hazard assessment subsystem, vulnerability evaluation subsystem and risk prediction subsystem. In the system, landslide hazard assessment, vulnerability evaluation, risk predictions are carried out automatically based on irregular units. At last the landslide hazard and risk map of the study area is compiled. During the whole procedure, Matter-Element Model, Artificial Neural Network, and Information Model are used as assessment models. This system provides an effective way for the landslide hazard information management and risk prediction of each district in the Reservoir of Three Gorge Project. The result of the assessment can be a gist and ensure for the land planning and the emigration project in Badong.

  20. Risk analysis model for landslide mass of high slope in dam area

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to identify the threat of reservoir bank landslide to dam safety and reduce the risk of dam failure,impact factors of the landslide are analyzed.The concept of landslide risk degree is put forward to measure the threat of landslide to dam safety.The monotony of the landslide risk assessment function which changes with different affecting factors is analyzed qualitatively.Based on gene automatic programming,a data mining model of the landslide risk assessment function is constructed combined with impact factors of reservoir bank landslide on dam safety.And the assessment function of landslide risk has been excavated and established according to practical project information,which provides a valuable reference for analyzing the impact of landslide on dam risk.

  1. Sept 2013 NFHL Flood Hazard Areas

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  2. Results of a multidisciplinary study in the Marmara Supersite, on-shore area: Büyükçekmece landslide

    Science.gov (United States)

    Coccia, Stella; Bigarré, Pascal; Ergintav, Semih; Ozel, Oguz; Yalcinkaya, Esref; Ozalabey, Serdar; Bourdeau, Céline; Martino, Salvatore; Lenti, Luca; Zucca, Francesco; Moro, Marco

    2016-04-01

    The MARsite project (Nov 2012-Avril 2016), one of the three SUPERSITE concept FP7 projects, deals with the definition of new directions in seismic hazard assessment through focused earth observation in the Marmara Supersite. This project gathers different research groups in a comprehensive monitoring activity developed in the Sea of Marmara Region. This region is one of the most densely populated parts of Europe and rated at high seismic risk level since the 1999 Izmit and Duzce devastating earthquakes. The 6th Work Package of MARsite project offered a very valuable frame to undertake simultaneous and complementary scientific investigations and studies to get deeper insight in the seismic and rainfall landslide topic, ranging from methodology to hazard assessment tool. This package focused on two sub-regional areas of high interest. First, the Avcilar-Beylikdüzü peninsula, located westwards of Istanbul, is a highly urbanized concentrated landslide prone area, showing high susceptibility to both rainfalls while affected by very significant seismic site effects. Second, the off-shore entrance of the Izmit Gulf, close to the termination of the surface rupture of the 1999 earthquake, that shows an important slump mass facing the Istanbul coastline. For the on-shore area, after refining the landslide inventory of the peninsula, one of the nine inventoried rototranslational landslides was chosen as pilot site, the Büyükçekmece landslide. This landslide has a continuous activity and a composite mechanism (including several secondary sliding surfaces); it moves at low velocity and involves sandy and clayey deposits of a local Cenozoic Succession damaging several infrastructures, such as buildings and roads. Various geophysical campaigns were carried out and then a field temporary multi-parameter monitoring was set up, composed of GPS-RTK, two seismic probes, thermometer, rain-gauge, moisture, etc.. Hyperspectral and Dinsar imagery technologies were also deployed to

  3. Modeling the potential distribution of shallow-seated landslides using the weights of evidence method and a logistic regression model:a case study of the Sabae Area, Japan

    Institute of Scientific and Technical Information of China (English)

    Ru-Hua SONG; Daimaru HIROMU; Abe KAZUTOKI; Kurokawa USIO; Matsuura SUMIO

    2008-01-01

    A number of statistical methods are typically used to effectively predict potential landslide distributions.In this study two multivariate statistical analysis methods were used (weights of evidence and logistic regression) to predict the potential distribution of shallow-seated landslides in the Kamikawachi area of Sabae City,Fukui Prefecture,Japan.First,the dependent variable (shallow-seated landslides) was divided into presence and absence,and the independent variables (environmental factors such as slope and altitude) were categorized according to their characteristics.Then,using the weights of evidence (WE) method,the weights of pairs comprising presence (w+(i) ) or absence (w-(i) ),and the contrast values for each category of independent variable (evidence),were calculated.Using the method that integrated the weights of evidence method and a logistic regression model,score values were calculated for each category of independent variable.Based on these contrast values,three models were selected to sum the score values of every gird in the study area.According to a receiver operating characteristic curve analysis (ROC),model 2 yielded the best fit for predicting the potential distribution of shallow-seated landslide hazards,with 89% correctness and a 54.5% hit ratio when the occurrence probability (OP) of landslides was 70%.The model was tested using data from an area close to the study region,and showed 94% correctness and a hit ratio of 45.7% when the OP of landslides was 70%.Finally,the potential distribution of shallow-seated landslides,based on the OP,was mapped using a geographical information system.

  4. COUPLING ANALYSIS OF CONTROL FACTORS BETWEEN EARTHQUAKEINDUCED LANDSLIDES AND SUBSEQUENT RAINFALL-INDUCED LANDSLIDES IN EPICENTER AREA OF WENCHUAN EARTHQUAKE%汶川地震强震区地震诱发滑坡与后期降雨诱发滑坡控制因子耦合分析

    Institute of Scientific and Technical Information of China (English)

    齐信; 唐川; 陈州丰; 邵长生

    2012-01-01

    the landslide area increased by68. 7%. Meanwhile, on the basis of remote sensing data interpretation, the paper further analyse the induced landslides , carries out the trends, hazard and risk evaluation, which provides a scientific prediction basis. The findings in this paper can be useful to the Wenchuan Earthquake restoration and reconstruction in disaster mitigation and preparedness and provide the decision-makers to carry out earthquake-induced landslides and rainfall-induced landslides scale contrast and control factor coupling analysis and the earthquake and rainfall coupling disasters chain mode.

  5. CLOSE RANGE DIGITAL PHOTOGRAMMETRY APPLIED TO TOPOGRAPHY AND LANDSLIDE MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    W.-C. Liu

    2016-06-01

    Full Text Available Landslide monitoring is a crucial tool for the prevention of hazards. It is often the only solution for the survey and the early-warning of large landslides cannot be stabilized. The objective of present study is to use a low-cost image system to monitor the active landslides. We adopted the direct linear transformation (DLT method in close range digital photogrammetry to measure terrain of landslide at the Huoyen Shan, Miaoli of central Taiwan and to compare measured results with e-GPS. The results revealed that the relative error in surface area was approximately 1.7% as comparing the photogrammetry with DLT method and e-GPS measurement. It showed that the close range digital photogrammetry with DLT method had the availability and capability to measure the landslides. The same methodology was then applied to measure the terrain before landslide and after landslide in the study area. The digital terrain model (DTM was established and then was used to calculate the volume of the terrain before landslide and after landslide. The volume difference before and after landslides was 994.16 m3.

  6. Close Range Digital Photogrammetry Applied to Topography and Landslide Measurements

    Science.gov (United States)

    Liu, Wen-Cheng; Huang, Wei-Che

    2016-06-01

    Landslide monitoring is a crucial tool for the prevention of hazards. It is often the only solution for the survey and the early-warning of large landslides cannot be stabilized. The objective of present study is to use a low-cost image system to monitor the active landslides. We adopted the direct linear transformation (DLT) method in close range digital photogrammetry to measure terrain of landslide at the Huoyen Shan, Miaoli of central Taiwan and to compare measured results with e-GPS. The results revealed that the relative error in surface area was approximately 1.7% as comparing the photogrammetry with DLT method and e-GPS measurement. It showed that the close range digital photogrammetry with DLT method had the availability and capability to measure the landslides. The same methodology was then applied to measure the terrain before landslide and after landslide in the study area. The digital terrain model (DTM) was established and then was used to calculate the volume of the terrain before landslide and after landslide. The volume difference before and after landslides was 994.16 m3.

  7. Landslide and tsunami hazard at Yate volcano, Chile as an example of edifice destruction on strike-slip fault zones

    Science.gov (United States)

    Watt, Sebastian F. L.; Pyle, David M.; Naranjo, José A.; Mather, Tamsin A.

    2009-07-01

    The edifice of Yate volcano, a dissected stratocone in the Andean Southern Volcanic Zone, has experienced multiple summit collapses throughout postglacial time restricted to sectors NE and SW of the summit. The largest such historic event occurred on 19th February 1965 when ˜6.1-10 × 106 m3 of rock and ice detached from 2,000-m elevation to the SW of the summit and transformed into a debris flow. In the upper part of the flow path, velocities are estimated to have reached 40 m s-1. After travelling 7,500 m and descending 1,490 m, the flow entered an intermontane lake, Lago Cabrera. A wavemaker of estimated volume 9 ± 3 × 106 m3 generated a tsunami with an estimated amplitude of 25 m and a run-up of ˜60 m at the west end of the lake where a settlement disappeared with the loss of 27 lives. The landslide followed 15 days of unusually heavy summer rain, which may have caused failure by increasing pore water pressure in rock mechanically weathered through glacial action. The preferential collapse directions at Yate result from the volcano’s construction on the dextral strike-slip Liquiñe-Ofqui fault zone. Movement on the fault during the lifetime of the volcano is thought to have generated internal instabilities in the observed failure orientations, at ˜10° to the fault zone in the Riedel shear direction. This mechanically weakened rock may have led to preferentially orientated glacial valleys, generating a feedback mechanism with collapse followed by rapid glacial erosion, accelerating the rate of incision into the edifice through repeated landslides. Debris flows with magnitudes similar to the 1965 event are likely to recur at Yate, with repeat times of the order of 102 years. With a warming climate, increased glacial meltwater due to snowline retreat and increasing rain, at the expense of snow, may accelerate rates of edifice collapse, with implications for landslide hazard and risk at glaciated volcanoes, in particular those in strike-slip tectonic

  8. Validation of landslide hazard assessment by means of GPS monitoring technique – a case study in the Dolomites (Eastern Alps, Italy

    Directory of Open Access Journals (Sweden)

    F. Tagliavini

    2007-01-01

    Full Text Available In the last years a research project aimed at the assessment of the landslide hazard and susceptibility in the high Cordevole river basin (Eastern Dolomites, Italy have been carried out. The hazard map was made adopting the Swiss Confederation semi-deterministic approach that takes into account parameters such as velocity, geometry and frequency of landslides. Usually these parameters are collected by means of geological and morphological surveys, historical archive researches, aerophotogrammetric analysis etc. In this framework however the dynamics of an instable slope can be difficult to determine. This work aims at illustrating some progress in landslide hazard assessment using a modified version of the Swiss Confederation semi-deterministic approach in which the values of some parameters have been refined in order to accomplish more reliable results in hazard assessment. A validation of the accuracy of these new values, using GPS and inclinometric measurements, has been carried out on a test site located inside the high Cordevole river basin.

  9. Total system hazards analysis for the western area demilitarization facility

    Science.gov (United States)

    Pape, R.; Mniszewski, K.; Swider, E.

    1984-08-01

    The results of a hazards analysis of the Western Area Demilitarization facility (WADF) at Hawthorne, Nevada are summarized. An overview of the WADF systems, the hazards analysis methodology that was applied, a general discussion of the fault tree analysis results, and a compilation of the conclusions and recommendations for each area of the facility are given.

  10. 76 FR 37893 - Loans in Areas Having Special Flood Hazards

    Science.gov (United States)

    2011-06-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY Office of Thrift Supervision Loans in Areas Having Special Flood Hazards AGENCY: Office of Thrift... collection. Title of Proposal: Loans in Areas Having Special Flood Hazards. OMB Number: 1550-0088....

  11. Land use change and landslide characteristics analysis for community-based disaster mitigation.

    Science.gov (United States)

    Chen, Chien-Yuan; Huang, Wen-Lin

    2013-05-01

    On August 8, 2009, Typhoon Morakot brought heavy rain to Taiwan, causing numerous landslides and debris flows in the Taihe village area of Meishan Township, Chiayi County, in south-central Taiwan. In the Taihe land is primary used for agriculture and land use management may be a factor in the area's landslides. This study explores Typhoon Morakot-induced landslides and land use changes between 1999 and 2009 using GIS with the aid of field investigation. Spot 5 satellite images with a resolution of 2.5 m are used for landslide interpretation and manually digitalized in GIS. A statistical analysis for landslide frequency-area distribution was used to identify the landslide characteristics associated with different types of land use. There were 243 landslides with a total area of 2.75 km(2) in the study area. The area is located in intrinsically fragile combinations of sandstone and shale. Typhoon Morakot-induced landslides show a power-law distribution in the study area. Landslides were mainly located in steep slope areas containing natural forest and in areas planted with bamboo, tea, and betel nut. Land covered with natural forest shows the highest landslide ratio, followed by bamboo, betel nut, and tea. Landslides thus show a higher ratio in areas planted with shallow root vegetation such as bamboo, betel nut, and tea. Furthermore, the degree of basin development is proportional to the landslide ratio. The results show that a change in vegetation cover results in a modified landslide area and frequency and changed land use areas have higher landslide ratios than non-changed. Land use management and community-based disaster prevention are needed in mountainous areas of Taiwan for hazard mitigation.

  12. Truth or Consequences Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  13. Indicator-based model to assess vulnerability to landslides in urban areas. Case study of Husi city (Eastern Romania)

    Science.gov (United States)

    Grozavu, Adrian; Ciprian Margarint, Mihai; Catalin Stanga, Iulian

    2013-04-01

    In the last three or four decades, vulnerability evolved from physical fragility meanings to a more complex concept, being a key element of risk assessment. In landslide risk assessment, there are a large series of studies regarding landslide hazard, but far fewer researches focusing on vulnerability measurement. Furthermore, there is still no unitary understanding on the methodological framework, neither any internationally agreed standard for landslide vulnerability measurements. The omnipresent common element is the existence of elements at risk, but while some approaches are limited to exposure, other focus on the degree of losses (human injuries, material damages and monetary losses, structural dysfunctions etc.). These losses are differently assessed using both absolute and relative values on qualitative or quantitative scales and they are differently integrated to provide a final vulnerability value. This study aims to assess vulnerability to landslides at local level using an indicator-based model applied to urban areas and tested for Husi town (Eastern Romania). The study region is characterized by permeable and impermeable alternating sedimentary rocks, monoclinal geological structure and hilly relief with impressive cuestas, continental temperate climate, and precipitation of about 500 mm/year, rising to 700 m and even more in some rainy years. The town is a middle size one (25000 inhabitants) and it had an ascending evolution in the last centuries, followed by an increasing human pressure on lands. Methodologically, the first step was to assess the landslide susceptibility and to identify in this way those regions within which any asset would be exposed to landslide hazards. Landslide susceptibility was assessed using the logistic regression approach, taking into account several quantitative and qualitative factors (elements of geology, morphometry, rainfall, land use etc.). The spatial background consisted in the Digital Elevation Model and all derived

  14. Tectonic control of complex slope failures in the Ameka River Valley (Lower Gibe Area, central Ethiopia): Implications for landslide formation

    Science.gov (United States)

    Kycl, Petr; Rapprich, Vladislav; Verner, Kryštof; Novotný, Jan; Hroch, Tomáš; Mišurec, Jan; Eshetu, Habtamu; Tadesse Haile, Ezra; Alemayehu, Leta; Goslar, Tomasz

    2017-07-01

    Even though major faults represent important landslide controlling factors, the role the tectonic setting in actively spreading rifts plays in the development of large complex landslides is seldom discussed. The Ameka complex landslide area is located on the eastern scarp of the Gibe Gorge, approximately 45 km to the west of the Main Ethiopian Rift and 175 km to the southwest of Addis Ababa. Investigation of the complex landslide failures required a combination of satellite and airborne data-based geomorphology, geological field survey complemented with structural analysis, radiocarbon geochronology and vertical electric sounding. The obtained observations confirmed the multiphase evolution of the landslide area. We have documented that, apart from climatic and lithological conditions, the main triggering factor of the Ameka complex landslide is the tectonic development of this area. The E-W extension along the NNE-SSW trending Main Ethiopian Rift is associated with the formation of numerous parallel normal faults, such as the Gibe Gorge fault and the almost perpendicular scissor faults. The geometry of the slid blocks of coherent lithology have inherited the original tectonic framework, which suggests the crucial role tectonics play in the fragmentation of the compact rock-masses, and the origin and development of the Ameka complex landslide area. Similarly, the main scarps were also parallel to the principal tectonic features. The local tectonic framework is dominated by faults of the same orientation as the regional structures of the Main Ethiopian Rift. Such parallel tectonic frameworks display clear links between the extension of the Main Ethiopian Rift and the tectonic development of the landslide area. The Ameka complex landslide developed in several episodes over thousands of years. According to the radiocarbon data, the last of the larger displaced blocks (representing only 2% of the total area) most likely slid down in the seventh century AD. The main

  15. Assessment of Hazardousness of Collapses, Landslides and Debris Flows in Guangdong%广东省崩塌、滑坡及泥石流灾害危险性评价与分析

    Institute of Scientific and Technical Information of China (English)

    余承君; 刘希林

    2012-01-01

    广东省地质灾害较为常见,崩塌、滑坡、泥石流是其中比较严重的3种类型.基于现有的泥石流危险度评价原理和方法,建立了可用于广东省崩塌、滑坡、泥石流灾害危险性的评价模型.以全省88个县级评价单元为基础,根据崩塌、滑坡、泥石流灾害危险度评价结果,将广东省共分为3个危险等级区,其中高度危险区8个县,占总数的9.1%;中度危险区60个县,占总数的68.2%;低度危险区20个县,占总数的22.7%,据此制成广东省崩塌、滑坡、泥石流灾害危险等级图.高度危险区主要位于粤北山区,危险度数值介于0.6~0.72之间;中度危险区连片分布,是全省崩塌、滑坡、泥石流灾害的主体部分,危险度数值介于0.4~0.6之间;低度危险区集中分布在平原区及低平台地区,危险度数值介于0.31~0.4之间.采用1994- 2009年广东省防灾减灾年鉴和广东省地质灾害防治规划(2001 -2015年)中的统计数据,验证了本文的研究成果与实际情况具有较高的一致性.%Collapses, landslides and debris flows are the main three Geological hazards in Guangdong. On the basis of the existing methodology for debris flow hazard assessment, this paper establishes a system of indexes for assessment of collapse, landslide and debris flow hazards in Guangdong, including assessing index choosing, assessing model establishment and modification, and assessing result analysis. According to the hazardousness assessing results of 88 units at county level, the province can be divided into three classes of hazardous areas. The high hazardous area has 8 counties and districts, accounting for 9.1% of the total, the moderate hazardous areas include 60 counties and districts, accounting for 68.2%, and the low hazardous area has 20 counties and districts, accounting for 22.7%. Accordingly a hazardousness class map of collapse, landslide and debris flow hazards in Guangdong is presented. The areas with

  16. Landslide susceptibility analysis using an artificial neural network model

    Science.gov (United States)

    Mansor, Shattri; Pradhan, Biswajeet; Daud, Mohamed; Jamaludin, Normalina; Khuzaimah, Zailani

    2007-10-01

    This paper deals with landslide susceptibility analysis using an artificial neural network model for Cameron Highland, Malaysia. Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys. Topographical/geological data and satellite images were collected and processed using GIS and image processing tools. There are ten landslide inducing parameters which are considered for the landslide hazards. These parameters are topographic slope, aspect, curvature and distance from drainage, all derived from the topographic database; geology and distance from lineament, derived from the geologic database; landuse from Landsat satellite images; soil from the soil database; precipitation amount, derived from the rainfall database; and the vegetation index value from SPOT satellite images. Landslide hazard was analyzed using landslide occurrence factors employing the logistic regression model. The results of the analysis were verified using the landslide location data and compared with logistic regression model. The accuracy of hazard map observed was 85.73%. The qualitative landslide susceptibility analysis was carried out using an artificial neural network model by doing map overlay analysis in GIS environment. This information could be used to estimate the risk to population, property and existing infrastructure like transportation network.

  17. Green-tuff landslide areas are beneficial for rice nutrition in Japan

    Directory of Open Access Journals (Sweden)

    Kazue Tazaki

    2006-12-01

    Full Text Available Japanese Islands are covered with weathered volcanic rocks and soils. Terraced rice field are located in green-tuff areas which are very fertile but where landslides occur associated to strong earthquakes. The Xray diffraction and X-ray fluorescence analyses of the soils in landslide area identified predominant smectite and Mg, Al, Si, K, Ti, Mn and Fe are main components. The rice leaf showed that S, Cl, K and Ca play important roles for nutrients in the area. Drainpipe systems have set up in the green- tuff areas to reduce the risks of landslides. Reddish brown microbial mats inhabited bacteria and diatom in the drainpipe outlets. The microbial mats are rich in Fe and PO4(3-. The iron bacteria in the ground water have a high metabolic rate suggesting that the weathering materials were produced by not only physical and chemical influence but also by microorganism. Many microorganisms attach to mineral surfaces and show their high impact in the water mineral chemistry in the landslide area. Bacteria in the green-tuff over landslide area play important roles for sustainable agriculture including rice nutrition.As Ilhas Japonesas são cobertas de rochas e solos vulcânicos intemperizados. Terraços de campos de arroz estão comumente localizados em áreas de tufos verdes, as quais são férteis, mas estão geralmente sujeitas a trágicos deslizamentos de terra associados a grandes terremotos. As análises dos solos por difração e fluorescência de raios-X em áreas de deslizamento identificam a predominância de esmectitas, cujos componentes principais são Mg, Al, Si, K, Ca, Ti, Mn, e Fe como principais componentes. A palha de arroz mostrou que S, Cl, K, e Ca têm importantes papéis para a nutrição dos solos dessa área. Sistemas de tubos de deslizamento foram instalados nestas áreas detufos verdes de forma a reduzir os riscos de deslizamentos. Nas saídas dos tubos de descarga se formou uma esteira de algas microbianas marrom avermelhadas

  18. Coseismic and Post-seismic landsliding: insights from seismological modeling and landslide map time series.

    Science.gov (United States)

    Marc, Odin; Hovius, Niels; Meunier, Patrick; Uchida, Taro; Gorum, Tolga

    2016-04-01

    Earthquakes impart a catastrophic forcing on hillslopes, that often lead to widespread landsliding and can contribute significantly to sedimentary and organic matter fluxes. We present a new expression for the total area and volume of populations of earthquake-induced landslides.This model builds on a set of scaling relationships between key parameters, such as landslide density, ground acceleration, fault size, earthquake source depth and seismic moment, derived from geomorphological and seismological observations. To assess the model we have assembled and normalized a catalogue of landslide inventories for 40 earthquakes. We have found that low landscape steepness systematically leads to over-prediction of the total area and volume of landslides.When this effect is accounted for, the model is able to predict within a factor of 2 the landslide areas and associated volumes for about two thirds of the cases in our databases. This is a significant improvement on a previously published empirical expression based only on earthquake moment. This model is suitable for integration into landscape evolution models, and application to the assessment of secondary hazards and risks associated with earthquakes. However, it only models landslides associated to the strong ground shaking and neglects the intrinsic permanent damage that also occurred on hillslopes and persist for longer period. With time series of landslide maps we have constrained the magnitude of the change in landslide susceptibility in the epicentral areas of 4 intermediate to large earthquakes. We propose likely causes for this transient ground strength perturbations and compare our observations to other observations of transient perturbations in epicentral areas, such as suspended sediment transport increases, seismic velocity reductions and hydrological perturbations. We conclude with some preliminary observations on the coseismic mass wasting and post-seismic landslide enhancement caused by the 2015 Mw.7

  19. Sliding zone identification of landslide area using resistivity method in Cijambe, Subang West Java

    Science.gov (United States)

    Ardi, Nanang Dwi; Iryanti, Mimin

    2016-02-01

    Subang is an area which consists of hill and mountain. This area is also categorized as disaster-prone zone. An environment assessment should be carried out to prevent the landslide in the future. Sliding zone was associated with clay stones that were indicated by low resistivity zone. Technical measurements of resistivity method made are lateral mapping using the Wenner configuration with electrode spacing of 2 meter to reach the end point of the track along 60 meter. Resistivity values obtained in the range of 15-35 Ωm, 30-215 Ωm, and 250-1700 Ωm which indicated clay mixed with rock layer that dominates below the surface, clay sandy and alluvial were gathered. From the two dimension model, it can be concluded that in the study area reveal the sliding zone was located on upper the low resistivity zone.

  20. Investigation of relationship between sediment yield and landslide in Iran

    Directory of Open Access Journals (Sweden)

    Samad Shadfar

    2012-07-01

    Full Text Available Landslides have been made irreversible damage to urban areas and economic in Iran. In this research, at first, for Investigation of relationship between landslide and sediment yield was recognized some of effective factors on Landslide. These Factors were processed with use of ILWIS and Arc GIS software’s. Landslide hazard zonation was done using Density Area and Index Overlay methods in GIS and evaluated them using Quality Sum index. In after phase, were determined sediment yield in each of them. Finally, occurrence rate landslide investigated in sediment yield zones. The results indicated that, slope, lithology and distance from the hydrographic network have the greatest impact on landslides. Most of the landslides have occurred in the 15-40% slope class, units of conglomerate and marl, and within one km of drainage network. On the other hand, the relationship between landslide frequency and distance of the fault was not a linear relationship and Almost 60 %of landslides have occurred distance of one km of the faults. Evaluation using Quality Sum index showed that the density Area has a more logical answer and as Appropriate method will be introduced in the basin. Investigation of deposition potential in sub-basins showed that Javaherdeh sub basin with 92.74 deposition potential is the first priority. Nedasht and latmohalleh sub basins, each with a deposition potential of 20.08 are the next priorities. Relationship between landslide area and deposition potential were identified as 8/91% of the landslides in the area of low And about 79 percent of landslides are located in high and very high deposition potentials.

  1. Application of a hybrid model of neural networks and genetic algorithms to evaluate landslide susceptibility

    Science.gov (United States)

    Wang, H. B.; Li, J. W.; Zhou, B.; Yuan, Z. Q.; Chen, Y. P.

    2013-03-01

    In the last few decades, the development of Geographical Information Systems (GIS) technology has provided a method for the evaluation of landslide susceptibility and hazard. Slope units were found to be appropriate for the fundamental morphological elements in landslide susceptibility evaluation. Following the DEM construction in a loess area susceptible to landslides, the direct-reverse DEM technology was employed to generate 216 slope units in the studied area. After a detailed investigation, the landslide inventory was mapped in which 39 landslides, including paleo-landslides, old landslides and recent landslides, were present. Of the 216 slope units, 123 involved landslides. To analyze the mechanism of these landslides, six environmental factors were selected to evaluate landslide occurrence: slope angle, aspect, the height and shape of the slope, distance to river and human activities. These factors were extracted in terms of the slope unit within the ArcGIS software. The spatial analysis demonstrates that most of the landslides are located on convex slopes at an elevation of 100-150 m with slope angles from 135°-225° and 40°-60°. Landslide occurrence was then checked according to these environmental factors using an artificial neural network with back propagation, optimized by genetic algorithms. A dataset of 120 slope units was chosen for training the neural network model, i.e., 80 units with landslide presence and 40 units without landslide presence. The parameters of genetic algorithms and neural networks were then set: population size of 100, crossover probability of 0.65, mutation probability of 0.01, momentum factor of 0.60, learning rate of 0.7, max learning number of 10 000, and target error of 0.000001. After training on the datasets, the susceptibility of landslides was mapped for the land-use plan and hazard mitigation. Comparing the susceptibility map with landslide inventory, it was noted that the prediction accuracy of landslide occurrence

  2. Site-specific landslide assessment in Alpine area using a reliable integrated monitoring system

    Science.gov (United States)

    Romeo, Saverio; Di Matteo, Lucio; Kieffer, Daniel Scott

    2016-04-01

    Rockfalls are one of major cause of landslide fatalities around the world. The present work discusses the reliability of integrated monitoring of displacements in a rockfall within the Alpine region (Salzburg Land - Austria), taking into account also the effect of the ongoing climate change. Due to the unpredictability of the frequency and magnitude, that threatens human lives and infrastructure, frequently it is necessary to implement an efficient monitoring system. For this reason, during the last decades, integrated monitoring systems of unstable slopes were widely developed and used (e.g., extensometers, cameras, remote sensing, etc.). In this framework, Remote Sensing techniques, such as GBInSAR technique (Groung-Based Interferometric Synthetic Aperture Radar), have emerged as efficient and powerful tools for deformation monitoring. GBInSAR measurements can be useful to achieve an early warning system using surface deformation parameters as ground displacement or inverse velocity (for semi-empirical forecasting methods). In order to check the reliability of GBInSAR and to monitor the evolution of landslide, it is very important to integrate different techniques. Indeed, a multi-instrumental approach is essential to investigate movements both in surface and in depth and the use of different monitoring techniques allows to perform a cross analysis of the data and to minimize errors, to check the data quality and to improve the monitoring system. During 2013, an intense and complete monitoring campaign has been conducted on the Ingelsberg landslide. By analyzing both historical temperature series (HISTALP) recorded during the last century and those from local weather stations, temperature values (Autumn-Winter, Winter and Spring) are clearly increased in Bad Hofgastein area as well as in Alpine region. As consequence, in the last decades the rockfall events have been shifted from spring to summer due to warmer winters. It is interesting to point out that

  3. Landslide prediction system in Slovenia (Masprem)

    Science.gov (United States)

    Šinigoj, Jasna; Jemec Auflič, Mateja; Krivic, Matija

    2017-04-01

    The landslide prediction system MASPREM has been developed in 2013 to (1) predict rainfall induced landslides on national and local level and (2) inform Civil Protection agency and inhabitants of an increased probability of landslide occurrences. A landslide prediction system on national level integrates three major components: (1) a landslide susceptibility map; (2) landslide triggering rainfall threshold values and (3) precipitation forecasting model's (i.e., ALADIN, INCA). Landslide prediction is also calculated on a local level, including exposure maps of inhabitants, buildings and different types of infrastructure to potential landslide occurrence at a scale of 1: 25,000 for 14 selected municipalities. MASPREM system runs in a 12 hour cycling mode, for 24 hours ahead. The results of the probability of landslide models are classified into five classes, with values ranging from one to five; where class one represents areas with a negligible landslide probability and class five areas with a very high landslide probability. It is a fully automated system based on open source software (PostgreSQL) and web applications for displaying results (Java, GDAL). When precipitation forecasting models are transferred to the GeoZS server the conversion process to raster data starts, stores data in a PostgreSQL database and performs the calculation. Based on final results, the WMS service that is responsible for the distribution of data through the service for download and review of results in a web application is created. In the period, from September 2013 to August 2016, MASPREM gave an alert about the probability of landslide occurrences in 84 cases. While the system has potential to become operational in use after the validation phase, there are also limitations related to the input data that should not be neglected: spatial resolution of the ALADIN model, the incomplete landslide inventory that is important for the validation, defining how many days of antecedent rainfall

  4. Brief Communication: Landslides triggered by the Ms =7.0 Lushan earthquake, China

    Directory of Open Access Journals (Sweden)

    X. L. Chen

    2013-08-01

    Full Text Available Earthquake-triggered landslide has drawn much attention in the world because of severe hazards it causes. The Ms =7.0 Lushan earthquake which occurred on 20 April 2013, China, in the Longmen Shan mountain region triggered more than 1000 landslides and really blocked many roads and exacerbated the overall transportation problems in the mountainous region. Preliminary landslides inventory is complied based on the high-resolution remote sensing images. Based on it, landslides spatial distribution characteristics and correlations between the occurrence of landslides with geologic and geomorphologic conditions are analyzed. Statistic analysis is conducted by using landslide point density (LPD, which is defined as the number of landslides per square kilometer. It is found that LPD have strong positive correlations with slope gradients, and the landslides are likely to occur in younger strata systems like Quaternary and Tertiary sediments. Spatially, the triggered landslides are controlled by the causative faults in their distribution and mainly concentrate around the epicenter. All the landslides are located within the area with seismic intensity ≥ VII and in scale with the seismic intensity. LPD decreases with increasing distance from the epicenter, and sometimes landslides are found densely presented along the roads in the mountainous. It is found that the empirical distance–magnitude relation are more suitable for estimating the landslides concentrated area during the Lushan earthquake.

  5. Landslide susceptibility mapping for rural development: Case studies and research findings from the Himalayas

    Science.gov (United States)

    Hearn, J.; Petley, D. N.

    2003-04-01

    In 2002 landslides caused a reported 346 human fatalities in the Himalayan Kingdom of Nepal. Over the last decade the total reported deaths due to landslides has exceeded 900. During the past 2-3 years in neighbouring Bhutan landslides have caused extensive damage to roads and other infrastructure, also leading to significant loss of life. Landslides, therefore, are major considerations in the siting of new infrastructure, the maintenance of existing facilities and the protection of rural communities and road users in the Himalayan region. Despite this, there is extremely limited information available on landslide hazards in the region, and the situation is a particular concern in Nepal and Bhutan. The Landslide Risk Assessment Project was established in 2000 to investigate cause-effect relationships in landslide occurrence and to develop simple techniques of landslide susceptibility mapping. A total of over 1300 landslides have been mapped from remote sensing and field surveys in six study areas in Nepal and Bhutan. GIS has been used to compare the spatial distribution of these landslides with a range of geological, terrain and land use factors. The research has shown that consistent relationships can be found between the location of landslides and rock type, geological structure, slope steepness and terrain classification. The results have positive implications for the assessment of landslide susceptibility for rural development planning in areas where limited data already exist.

  6. Wide-Area Landslide Deformation Mapping with Multi-Path ALOS PALSAR Data Stacks: A Case Study of Three Gorges Area, China

    Directory of Open Access Journals (Sweden)

    Xuguo Shi

    2016-02-01

    Full Text Available In recent years, satellite synthetic aperture radar interferometry (InSAR has been adopted as a spaceborne geodetic tool to successfully measure surface deformation of a few well-known landslides in the Three Gorges area. In consideration of the fact that most events of slope failure happened at places other than those famous landslides since the reservoir impoundment in 2003, focusing on a limited number of slopes is insufficient to meet the requirements of regional-scale landslide disaster prevention and early warning. As a result, it has become a vital task to evaluate the overall stability of slopes across the vast area of Three Gorges using wide-coverage InSAR datasets. In this study, we explored the approach of carrying out joint analysis of multi-path InSAR data stacks for wide-area landslide deformation mapping. As an example, three ALOS (Advanced Land Observing Satellite PALSAR (Phased Array type L-band Synthetic Aperture Radar data stacks of neighboring ascending paths covering the area along the Yangtze River from Fengjie to Zigui were analyzed. A key problem to be solved is the separation of the tropospheric signal from the interferometric phase, for which we employed a hybrid description model of the atmospheric phase screen (APS to improve APS estimation from time series interferograms. The estimated atmospheric phase was largely correlated with the seasonal rainfall in the temporal dimension. The experimental results show that about 30 slopes covering total areas of 48 km2 were identified to be landslides in active deformation and should be kept under routine surveillance. Analyses of time series displacement measurements revealed that most landslides in the mountainous area far away from Yangtze River suffered from linear deformation, whereas landslides located on the river bank were destabilized predominantly by the influences of reservoir water level fluctuation and rainfall.

  7. Application of multi-temporal landform analysis in landslide susceptibility assessment for mountainous highway - a case study in southeastern Taiwan

    Science.gov (United States)

    Liu-Xuan, Jian; Wei-Kai, Huang; Po-Shen, Lin

    2016-04-01

    This study divided a coastal mountainous highway into small sections with slope unit, plot the multi-temporal landslide inventories, and analyze the relationships between the revegetation areas of the existing landslide and newly activated landslide to calculate landslide status Index (LSI). The RI represents the multi-temporal status of landslide status in each slope unit; three statuses and their representing colors were defined in this study. Red representing slope unit with continuously landslides, yellow for those with previous landslide but stable and revegetating, green are those without landslides. The regression lines became one of the parameters in establishing landslide status map. The study area, 407K to 439K of Provincial Highway No. 9, located in southeastern Taiwan and is the most important transport corridor connecting southern Taiwan and the east coast. In 2009 this mountainous highway was hit by Typhoon Morakot and several landslides, debris slides were triggered in the study area. The debris blocked the traffic and residential communities alone the highway became isolated. To this date some section of the highway still suffer from landslide hazard and transportation had to be temporarily interrupted during some occasions. The landslide status map of this transport corridor was established combining the result of field investigation, remote sensing interpretation, and the regression lines of LSI. The preliminary result shows that out of the 258 slope units, 13 (5%) showing continuous landslides, 44 (17%) became stable and revegetating. The result of this study could provide better information for mountainous highway safety management.

  8. 14 CFR 417.223 - Flight hazard area analysis.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Flight hazard area analysis. 417.223 Section 417.223 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Flight Safety Analysis § 417.223 Flight hazard...

  9. Landslides and Slope Aspect in the Three Gorges Reservoir Area Based on GIS and Information Value Model

    Institute of Scientific and Technical Information of China (English)

    WU Caiyan; QIAO Jianping; WANG Meng

    2006-01-01

    Slope aspect is one of the indispensable internal factors besides lithology,relative elevation and slope degree.In this paper authors use information value model with Geographical Information System (GIS) technology to study how slope aspect contributes to landslide growth from Yunyang to Wushan segment in the Three Gorges Reservoir area, and the relationship between aspect and landslide growth is quantified.Through the research on 205 landslides examples,it is found that the slope contributes most whose aspect is towards south,southeast and southwest aspect contribute moderately,and other five aspects contribute little.The research result inosculates preferably with the fact.The result of this paper can provide potent gist to the construction of Three Gorges Reservoir area in future.

  10. Analysis of national and regional landslide inventories in Europe

    Science.gov (United States)

    Hervás, J.; Van Den Eeckhaut, M.

    2012-04-01

    A landslide inventory can be defined as a detailed register of the distribution and characteristics of past landslides in an area. Today most landslide inventories have the form of digital databases including landslide distribution maps and associated alphanumeric information for each landslide. While landslide inventories are of the utmost importance for land use planning and risk management through the generation of landslide zonation (susceptibility, hazard and risk) maps, landslide databases are thought to greatly differ from one country to another and often also within the same country. This hampers the generation of comparable, harmonised landslide zonation maps at national and continental scales, which is needed for policy and decision making at EU level as regarded for instance in the INSPIRE Directive and the Thematic Strategy for Soil Protection. In order to have a clear understanding of the landslide inventories available in Europe and their potential to produce landslide zonation maps as well as to draw recommendations to improve harmonisation and interoperability between landslide databases, we have surveyed 37 countries. In total, information has been collected and analysed for 24 national databases in 22 countries (Albania, Andorra, Austria, Bosnia and Herzegovina, Bulgaria, Czech Republic, Former Yugoslav Republic of Macedonia, France, Greece, Hungary, Iceland, Ireland, Italy, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and UK) and 22 regional databases in 10 countries. At the moment, over 633,000 landslides are recorded in national databases, representing on average less than 50% of the estimated landslides occurred in these countries. The sample of regional databases included over 103,000 landslides, with an estimated completeness substantially higher than that of national databases, as more attention can be paid for data collection over smaller regions. Yet, both for national and regional coverage, the data collection

  11. Real time remote monitoring and pre-warning system for Highway landslide in mountain area.

    Science.gov (United States)

    Zhang, Yonghui; Li, Hongxu; Sheng, Qian; Wu, Kai; Chen, Guoliang

    2011-06-01

    The wire-pulling trigger displacement meter with precision of 1 mm and the grid pluviometer with precision of 0.1 mm are used to monitor the surface displacement and rainfall for Highway slope, and the measured data are transferred to the remote computer in real time by general packet radio service (GPRS) net of China telecom. The wire-pulling trigger displacement meter, grid pluviometer, data acquisition and transmission unit, and solar power supply device are integrated to form a comprehensive monitoring hardware system for Highway landslide in mountain area, which proven to be economical, energy-saving, automatic and high efficient. Meantime, based on the map and geographic information system (MAPGIS) platform, the software system is also developed for three dimensional (3D) geology modeling and visualization, data inquiring and drawing, stability calculation, displacement forecasting, and real time pre-warning. Moreover, the pre-warning methods based on monitoring displacement and rainfall are discussed. The monitoring and forecasting system for Highway landslide has been successfully applied in engineering practice to provide security for Highway transportation and construction and reduce environment disruption. Copyright © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  12. COSMO-SkyMed Spotlight interometry over rural areas: the Slumgullion landslide in Colorado, USA

    Science.gov (United States)

    Milillo, Pietro; Fielding, Eric J.; Schulz, William H.; Delbridge, Brent; Burgmann, Roland

    2014-01-01

    In the last 7 years, spaceborne synthetic aperture radar (SAR) data with resolution of better than a meter acquired by satellites in spotlight mode offered an unprecedented improvement in SAR interferometry (InSAR). Most attention has been focused on monitoring urban areas and man-made infrastructure exploiting geometric accuracy, stability, and phase fidelity of the spotlight mode. In this paper, we explore the potential application of the COSMO-SkyMed® Spotlight mode to rural areas where decorrelation is substantial and rapidly increases with time. We focus on the rapid repeat times of as short as one day possible with the COSMO-SkyMed® constellation. We further present a qualitative analysis of spotlight interferometry over the Slumgullion landslide in southwest Colorado, which moves at rates of more than 1 cm/day.

  13. Application of a fast and efficient algorithm to detect areas with prerequisites for landslide in sensitive clays, Göta Älv, Sweden

    Science.gov (United States)

    Melchiorre, Caterina; Tryggvason, Ari

    2014-05-01

    In Sweden, landslide stability maps are based on the recognition of topographical and soil conditions. The topographical criterion is based on the ratio between height of the slope and its length. The calculation of this cross-sectional angle is straight forward in one dimension, but slightly more complicated in two dimensions and very computationally expensive in a GIS environment. We present an application of a fast and efficient computer algorithm based on slope and soil criteria in Göta Älv, southwest Sweden. The algorithm, compared to other software implementations of the cross-sectional angle criterion, guarantees a fast execution, the possibility to insert several threshold values of the cross-sectional angle and the use of information on bedrock elevation. As input maps we used a 1:50000 Quaternary soil map, a DEM at 2x2 m pixel resolution, and a bedrock elevation map. We used two sets of cross-sectional angle thresholds, the first one derived from stability calculation and the second one assessed through the relationship between QCSI (i.e., estimated value of the sensitivity) and the cross-sectional angle calculated from the landslide scar database. A comparison between the results of the algorithm using or not using the bedrock information was also performed. The produced maps were validated by using the landslide scar database and a hazard map. The results show that the use of bedrock information decreases the calculated areas with prerequisites for landslides, whereas not decreasing the performance of the algorithm. The maps produced by using the two different sets of cross-angle thresholds are very similar and show similar results in the validation. This means that it would be possible to extent this methodology in areas without geotechnical information by using less expensive data such as the QCSI. Moreover, the use of several cross-sectional angle thresholds is not possible in other software implementations available at the moment. This means that

  14. Delineation of Landslide Prone Areas based on Geotechnical and Mineralogical Evaluation of Rocks and Soil to Understand the Failure Zones in a part of Alaknanda Valley, Garhwal Himalaya, India

    Science.gov (United States)

    Asthana, H.; Singh, N.; Sen, R.; Vishwakarma, C. A.; Singh, P.; Rena, V.; Mukherjee, S.

    2016-12-01

    The exclusive physiographic, tectonic and climatic conditions, along with natural and anthropogenic factors make the Himalayan terrain prone to land failure. The land which can be used for the developmental activities are severely limited. Increasing population density, societal requirements has put stress on the same quantum of land and created considerable anthropogenic problems in landscape equilibrium. In present study thematic maps have been developed for the Alaknanda valley in the Garhwal Himalaya of Uttrakhand to assess the potential landslide hazard zones. This has been done using remote sensing GIS data, topographic maps and field investigations. Based on above results landslide hazard zonation has been done to determine the spatio-temporal extent of landslide occurrence and vulnerability. Outlook of the slopes and identification of the discontinuities present in the terrain was done on the basis of representative samples through field investigations. Grain size analysis of the following samples was carried out to estimate the percentage sand, silt and clay content of the soil. Based on the proportions of different particle sizes, a soil textural category may be assigned to the samples. Results indicated that the landslides along the section of Devprayag-Badrinath National Highway are mainly debris slides, debris flows, rock slides and rock falls. Following landslide masses are chiefly composed of boulders, rock fragments and soil. Debris flows are mostly restrained along lines of natural drainage. The area is under severe anthropogenic as well as natural influence which can be further responsible for increase in the shear stress beyond the threshold level, thus decreasing the slope stability resulting in failure zones. A high resolution remotely sensed data in digital form has been proved to be an essential tool for the preparation, interpretation and analysis of the data obtained in the GIS environment. Further mineralogical evaluations are done to

  15. Distributed modelling of shallow landslides triggered by intense rainfall

    Directory of Open Access Journals (Sweden)

    G. B. Crosta

    2003-01-01

    Full Text Available Hazard assessment of shallow landslides represents an important aspect of land management in mountainous areas. Among all the methods proposed in the literature, physically based methods are the only ones that explicitly includes the dynamic factors that control landslide triggering (rainfall pattern, land-use. For this reason, they allow forecasting both the temporal and the spatial distribution of shallow landslides. Physically based methods for shallow landslides are based on the coupling of the infinite slope stability analysis with hydrological models. Three different grid-based distributed hydrological models are presented in this paper: a steady state model, a transient "piston-flow" wetting front model, and a transient diffusive model. A comparative test of these models was performed to simulate landslide occurred during a rainfall event (27–28 June 1997 that triggered hundreds of shallow landslides within Lecco province (central Southern Alps, Italy. In order to test the potential for a completely distributed model for rainfall-triggered landslides, radar detected rainfall intensity has been used. A new procedure for quantitative evaluation of distributed model performance is presented and used in this paper. The diffusive model results in the best model for the simulation of shallow landslide triggering after a rainfall event like the one that we have analysed. Finally, radar data available for the June 1997 event permitted greatly improving the simulation. In particular, radar data allowed to explain the non-uniform distribution of landslides within the study area.

  16. Landslide Susceptibility Mapping in Vertical Distribution Law of Precipitation Area: Case of the Xulong Hydropower Station Reservoir, Southwestern China

    Directory of Open Access Journals (Sweden)

    Chen Cao

    2016-06-01

    Full Text Available This study focused on landslide susceptibility analysis mapping of the Xulong hydropower station reservoir, which is located in the upstream of Jinsha River, a rapidly uplifting region of the Tibetan Plateau region. Nine factors were employed as landslide conditioning factors in landslide susceptibility mapping. These factors included the slope angle, slope aspect, curvature, geology, distance-to-fault, distance-to-river, vegetation, bedrock uplift and annual precipitation. The rapid bedrock uplift factor was represented by the slope angle. The eight factors were processed with the information content model. Since this area has a significant vertical distribution law of precipitation, the annual precipitation factor was analyzed separately. The analytic hierarchy process weighting method was used to calculate the weights of nine factors. Thus, this study proposed a component approach to combine the normalized eight-factor results with the normalized annual precipitation distribution results. Subsequently, the results were plotted in geographic information system (GIS and a landslide susceptibility map was produced. The evaluation accuracy analysis method was used as a validation approach. The landslide susceptibility classes were divided into four classes, including low, moderate, high and very high. The results show that the four susceptibility class ratios are 12.9%, 35.06%, 34.11%and 17.92% of the study area, respectively. The red belt in the high elevation area represents the very high susceptibility zones, which followed the vertical distribution law of precipitation. The prediction accuracy was 85.74%, which meant that the susceptibility map was confirmed to be reliable and reasonable. This susceptibility map may contribute to averting the landslide risk in the future construction of the Xulong hydropower station.

  17. Rainfall thresholds for shallow landslides occurrence in Calabria, southern Italy

    Directory of Open Access Journals (Sweden)

    C. Vennari

    2013-09-01

    systems. The thresholds can also be used for landslide hazard and risk assessments, and for erosion and landscape evolution studies, in the study area and in similar physiographic regions in the Mediterranean area.

  18. Evaluating the impact of climate change on landslide occurrence, hazard, and risk: from global to regional scale.

    Science.gov (United States)

    Gariano, Stefano Luigi; Guzzetti, Fausto

    2017-04-01

    According to the fifth report of the Intergovernmental Panel on Climate Change, "warming of the climate system is unequivocal". The influence of climate changes on slope stability and landslides is also undisputable. Nevertheless, the quantitative evaluation of the impact of global warming, and the related changes in climate, on landslides remains a complex question to be solved. The evidence that climate and landslides act at only partially overlapping spatial and temporal scales complicates the evaluation. Different research fields, including e.g., climatology, physics, hydrology, geology, hydrogeology, geotechnics, soil science, environmental science, and social science, must be considered. Climatic, environmental, demographic, and economic changes are strictly correlated, with complex feedbacks, to landslide occurrence and variation. Thus, a holistic, multidisciplinary approach is necessary. We reviewed the literature on landslide-climate studies, and found a bias in their geographical distribution, with several studies centered in Europe and North America, and large parts of the world not investigated. We examined advantages and drawbacks of the approaches adopted to evaluate the effects of climate variations on landslides, including prospective modelling and retrospective methods that use landslide and climate records, and paleo-environmental information. We found that the results of landslide-climate studies depend more on the emission scenarios, the global circulation models, the regional climate models, and the methods to downscale the climate variables, than on the description of the variables controlling slope processes. Using ensembles of projections based on a range of emissions scenarios would reduce (or at least quantify) the uncertainties in the obtained results. We performed a preliminary global assessment of the future landslide impact, presenting a global distribution of the projected impact of climate change on landslide activity and abundance

  19. Landslide susceptibility assessment of SE Bartin (West Black Sea region, Turkey by artificial neural networks

    Directory of Open Access Journals (Sweden)

    M. Ercanoglu

    2005-01-01

    Full Text Available Landslides are significant natural hazards in Turkey, second only to earthquakes with respect to economic losses and casualties. The West Black Sea region of Turkey is known as one of the most landslide-prone regions in the country. The work presented in this paper is aimed at evaluating landslide susceptibility in a selected area in the West Black Sea region using Artificial Neural Network (ANN method. A total of 317 landslides were identified and mapped in the area by extensive field work and by use of air photo interpretations to build a landslide inventory map. A landslide database was then derived automatically from the landslide inventory map. To evaluate landslide susceptibility, six input parameters (slope angle, slope aspect, topographical elevation, topographical shape, wetness index, and vegetation index were used. To obtain maps of these parameters, Digital Elevation Model (DEM and ASTER satellite imagery of the study area were used. At the first stage, all data were normalized in [0, 1] interval, and parameter effects on landslide occurrence were expressed using Statistical Index values (Wi. Then, landslide susceptibility analyses were performed using an ANN. Finally, performance of the resulting map and the applied methodology is discussed relative to performance indicators, such as predicted areal extent of landslides and the strength of relation (rij value. Much of the areal extents of the landslides (87.2% were classified as susceptible to landsliding, and rij value of 0.85 showed a high degree of similarity. In addition to these, at the final stage, an independent validation strategy was followed by dividing the landslide data set into two parts and 82.5% of the validation data set was found to be correctly classified as landslide susceptible areas. According to these results, it is concluded that the map produced by the ANN is reliable and methodology applied in the study produced high performance, and satisfactory results.

  20. Artificial Neural Network Model for Discrimination of Stability of Ancient Landslide in Impounding Area of Three Gorges Project, China

    Institute of Scientific and Technical Information of China (English)

    Zhou Pinggen

    2003-01-01

    The factors of geomorphology, geological setting, effect of ground water and environment dynamic factors (e. g. rainfall and artificial water recharge) should be integrated in the discrimination of the stability of the ancient landslide. As the criterion of landslide stability has been studied, the artificial neural network model was then applied to discriminate the stability of the ancient landslide in the impounding area of the Three Gorges project on the Yangtze River, China. The model has the property of self-adaptive identifying and integrating complex qualitative factors and quantitative factors. The results of the artificial neural network model are coincided well with what were gained by classical limit equilibrinm analysis (the Bishop method and Janbu method) and by other comprehensive discrimination methods.

  1. An approach to reduce mapping errors in the production of landslide inventory maps

    Directory of Open Access Journals (Sweden)

    M. Santangelo

    2015-07-01

    Full Text Available Landslide inventory maps (LIMs show where landslides have occurred in an area, and provide information useful to different types of landslide studies, including susceptibility and hazard modelling and validation, risk assessment, erosion analyses, and to evaluate relationships between landslides and geological settings. Despite recent technological advancements, visual interpretation of aerial photographs (API remains the most common method to prepare LIMs. In this work, we present a new semi-automatic procedure that exploits GIS technology for the digitalization of landslide data obtained through API. To test the procedure, and to compare it to a consolidated landslide mapping method, we prepared two LIMs starting from the same set of landslide API data, which were digitalized (a manually adopting a consolidated visual transfer method, and (b adopting our new semi-automatic procedure. Results indicate that the new semi-automatic procedure is more efficient and results in a more accurate LIM. With the new procedure, the landslide positional error decreases with increasing landslide size following a power-law. We expect that our work will help adopt standards for transferring landslide information from the aerial photographs to a digital landslide map, contributing to the production of accurate landslide maps.

  2. Assessment of landslide distribution map reliability in Niigata prefecture - Japan using frequency ratio approach

    Science.gov (United States)

    Rahardianto, Trias; Saputra, Aditya; Gomez, Christopher

    2017-07-01

    Research on landslide susceptibility has evolved rapidly over the few last decades thanks to the availability of large databases. Landslide research used to be focused on discreet events but the usage of large inventory dataset has become a central pillar of landslide susceptibility, hazard, and risk assessment. Indeed, extracting meaningful information from the large database is now at the forth of geoscientific research, following the big-data research trend. Indeed, the more comprehensive information of the past landslide available in a particular area is, the better the produced map will be, in order to support the effective decision making, planning, and engineering practice. The landslide inventory data which is freely accessible online gives an opportunity for many researchers and decision makers to prevent casualties and economic loss caused by future landslides. This data is advantageous especially for areas with poor landslide historical data. Since the construction criteria of landslide inventory map and its quality evaluation remain poorly defined, the assessment of open source landslide inventory map reliability is required. The present contribution aims to assess the reliability of open-source landslide inventory data based on the particular topographical setting of the observed area in Niigata prefecture, Japan. Geographic Information System (GIS) platform and statistical approach are applied to analyze the data. Frequency ratio method is utilized to model and assess the landslide map. The outcomes of the generated model showed unsatisfactory results with AUC value of 0.603 indicate the low prediction accuracy and unreliability of the model.

  3. A GRASS GIS-based deterministic model for shallow and deep-seated landslide susceptibility analysis over large areas

    Science.gov (United States)

    Mergili, Martin; Marchesini, Ivan; Rossi, Mauro; Guzzetti, Fausto; Fellin, Wolfgang

    2013-04-01

    Various deterministic slope stability models, based on the assumption of an infinite slope with a plane, slope-parallel failure plane, have been proposed in the literature. These models are commonly implemented in a GIS environment and are mostly used to model shallow landslides. Other models consider the three-dimensional geometry of possible slope failures and assume an ellipsoidal sliding surface. Such models are best suited to investigate deep-seated landslides. The latter models rely on complex neighbourhood relationships and are difficult to implement in a GIS environment. Here, we present a GIS-based landslide modelling tool that considers the three-dimensional geometry of the sliding surfaces and is capable of dealing with shallow and deep-seated failures. The model is developed in the GRASS GIS software as the C-based raster module r.rotstab, and adopts a modification of the three-dimensional sliding surface model proposed by Hovland and revised and extended by Xie and co-workers. Given a Digital Elevation Model and a set of thematic layers, the model evaluates slope stability for a large number of randomly selected potential slip surfaces, ellipsoidal in shape. Truncated ellipsoids can be used to model the presence of shallow weak layers in the soil or the bedrock. Any single raster cell may be intersected by multiple sliding surfaces, each associated with a computed safety factor. For each grid cell, the lowest value of the safety factor and the depth of the associated slip surface are stored. This information can be used to obtain a spatial overview of the potentially unstable regions in the study area. In addition, a landslide susceptibility index in the range 0 - 1 is calculated. The index relates the number of unstable slip surfaces to the total number of slip surfaces simulated for each pixel. We tested the model in the Collazzone area, Umbria, Central Italy, which is susceptible to landslides of different types. The presence of both shallow

  4. The Landslide Handbook - A Guide to Understanding Landslides

    Science.gov (United States)

    Highland, Lynn M.; Bobrowsky, Peter

    2008-01-01

    This handbook is intended to be a resource for people affected by landslides to acquire further knowledge, especially about the conditions that are unique to their neighborhoods and communities. Considerable literature and research are available concerning landslides, but unfortunately little of it is synthesized and integrated to address the geographically unique geologic and climatic conditions around the globe. Landslides occur throughout the world, under all climatic conditions and terrains, cost billions in monetary losses, and are responsible for thousands of deaths and injuries each year. Often, they cause long-term economic disruption, population displacement, and negative effects on the natural environment. Outdated land-use policies may not always reflect the best planning for use of land that is vulnerable to landslides. The reasons for poor or nonexistent land-use policies that minimize the perceived or actual danger and damage potential from geologic hazards are many and encompass the political, cultural, and financial complexities and intricacies of communities. Landslides often are characterized as local problems, but their effects and costs frequently cross local jurisdictions and may become State or Provincial or national problems. Growing populations may be limited in their geographic expansion, except to occupy unstable, steep, or remote areas. Often, stabilizing landslide-scarred areas is too costly, and some inhabitants have no other places to relocate. Fortunately, simple, 'low-tech' precautions and actions can be adopted to at least ensure an individual's immediate safety, and this handbook gives a brief overview of many of these options. We strongly suggest that, where possible, the assistance of professional engineers/geologists or those experienced in the successful mitigation of unstable slopes be consulted before actions are taken. This handbook helps homeowners, community and emergency managers, and decisionmakers to take the positive

  5. ACTUAL LANDSLIDES AS MOST OBJECTIVE STANDARD FOR VALIDA-TION OF LANDSLIDE HAZARD ASSESSMENT RESULT%实际滑坡是滑坡危险性评价结果合理性检验最好的标准

    Institute of Scientific and Technical Information of China (English)

    许冲

    2013-01-01

    王涛等“基于简化Newmark位移模型的区域地震滑坡危险性快速评估---以汶川MS 8.0级地震为例”一文的地震滑坡危险性快速评价结果与2008年汶川地震触发实际滑坡空间分布的相关性较低。本文试图通过对该文中基础数据、分析处理过程、研究结果的分析与讨论,找出这种相关性较低的原因。结果表明值得针对王涛等文章中的Arias烈度分布数据的准确性、工程地质岩组的划分情况、汶川地震滑坡危险性评价结果的客观性共三个方面开展更深入的分析与研究。本文对探索与发掘更客观的地震滑坡危险性评价模型起到了积极的作用。%A relatively low correlation appeared between the result from the published paper of Wang Tao et al. named“Case study on rapid assessment of regional seismic landslide hazard based on simplified Newmark displace-ment model:Wenchuan MS 8.0 earthquake”and spatial distribution pattern of actual landslides triggered by the 2008 Wenchuan earthquake.The main purpose of this comment or discussion is to analyze the reasons of the low correlation by analyzing and discussing of basic data,data analysis process,and results from that paper from Wang Tao and his research teams.The results suggest that Wang Tao and his teams carry out a more in-depth study in three aspects,include accuracy of the Arias intensity data,engineering geology lithology formation groupings,and validation of the Wenchuan earthquake-triggered landslides hazard assessment.This comment plays a positive role on exploring more scientific landslide hazard assessment models.

  6. National Map Data Base On Landslide Prerequisites In Clay and Silt Areas - Development of Prototype

    Science.gov (United States)

    Viberg, Leif

    Swedish geotechnical institute, SGI, has in co-operation with Swedish geologic survey, Lantmateriet (land surveying) and Swedish Rescue Service developed a theme database on landslide prerequisites in clay and silt areas. The work is carried out on commission of the Swedish government. A report with suggestions for production of the database has been delivered to the government. The database is a prototype, which has been tested in an area in northern Sweden. Recommended presentation map scale is about 1:50 000. Distribution of the database via Internet is discussed. The aim of the database is to use it as a modern planning tool in combination with other databases, e g databases on flooding prognoses. The main use is supposed to be in early planning stages, e g for new building and infrastructure development and for risk analyses. The database can also be used in more acute cases, e g for risk analyses and rescue operations in connection with flooding over large areas. Users are supposed to be municipal and county planners and rescue services, infrastructure planners, consultants and assurance companies. The database is constructed by combination of two existing databases: Elevation data and soil map data. The investigation area is divided into three zones with different stability criteria: 1. Clay and silt in sloping ground or adjoining water. 2. Clay and silt in flat ground. 3. Rock and other soils than clay and silt. The geometrical and soil criteria for the zones are specified in an algoritm, that will do the job to sort out the different zones. The algoritm is thereby using data from the elevation and soil databases. The investigation area is divided into cells (raster format) with 5 x 5 m side length. Different algoritms had to be developed before reasonable calculation time was reached. The theme may be presented on screen or as a map plot. A prototype map has been produced for the test area. A description is accompanying the map. The database is suggested

  7. Shallow Landslide Assessment using SINMAP in Laguna, Philippines

    Science.gov (United States)

    Bonus, A. A. B.; Rabonza, M. L.; Alemania, M. K. B.; Alejandrino, I. K.; Ybanez, R. L.; Lagmay, A. M. A.

    2014-12-01

    Due to the tectonic environment and tropical climate in the Philippines, both rain-induced and seismic-induced landslides are common in the country. Numerous hazard mapping activities are regularly conducted by both academic and government institutions using various tools and software. One such software is Stability Index Mapping (SINMAP), a terrain stability mapping tool applied to shallow translational landslide phenomena controlled by shallow groundwater flow convergence. SINMAP modelling combines a slope stability model with a steady-state hydrology model to delineate areas prone to shallow landslides. DOST- Project NOAH, one of the hazard-mapping initiatives of the government, aims to map all landslide hazard in the Philippines using both computer models as well as validating ground data. Laguna, located in the island of Luzon, is one such area where mapping and modelling is conducted. SINMAP modelling of the Laguna area was run with a 5-meter Interferomteric Synthetic Aperture Radar (IFSAR) derived digital terrain model (DTM). Topographic, soil-strength and physical hydrologic parameters, which include cohesion, angle of friction, bulk density and hydraulic conductivity, were assigned to each pixel of a given DTM grid to compute for the corresponding factor of safety. The landslide hazard map generated using SINMAP shows 2% of the total land area is highly susceptible in Santa Mara, Famy, Siniloan, Pangil, Pakil and Los Baἦos Laguna and 10% is moderately susceptible in the eastern parts of Laguna. The data derived from the model is consistent with both ground validation surveys as well as landslide inventories derived from high resolution satellite imagery from 2003 to 2013. With these combined computer and on-the-ground data, it is useful in identifying no-build zone areas and in monitoring activities of the local government units and other agencies concerned. This provides a reasonable delineation of hazard zones for shallow landslide susceptible areas of

  8. Predicting global landslide spatiotemporal distribution: Integrating landslide susceptibility zoning techniques and real-time satellite rainfall estimates

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Landslides triggered by rainfall can possibly be foreseen in real time by jointly using rainfall intensity-duration thresholds and information related to land surface susceptibility. However, no system exists at either a national or a global scale to monitor or detect rainfall conditions that may trigger landslides due to the lack of sufficient ground-based observing network in many parts of the world. Recent advances in satellite remote sensing technology and increasing availability of high-resolution geospatial products around the globe have provided an unprecedented opportunity for such a study. In this paper, a framework for developing a preliminary real-time prediction system to identify where rainfall-triggered landslides will occur is proposed by combining two necessary components: surface landslide susceptibility and a real-time space-based rainfall analysis system (http://trmm.gsfc.nasa.govV First, a global landslide susceptibility map is derived from a combination of semi-static global surface characteristics (digital elevation topography, slope, soil types, soil texture, land cover classification, etc.) using a GIS weighted linear combination approach. Second, an adjusted empirical relationship between rainfall intensity-duration and landslide occurrence is used to assess landslide hazards at areas with high susceptibility. A major outcome of this work is the availability for the first time of a global assessment of landslide hazards, which is only possible because of the utilization of global satellite remote sensing products. This preliminary system can be updated continuously using the new satellite remote sensing products. This proposed system, if pursued through wide interdisciplinary efforts as recommended herein, bears the promise to grow many local landslide hazard analyses into a global decision-making support system for landslide disaster preparedness and mitigation activities across the world.

  9. Experimental observation and modelling of rock - water interaction in a landslide-prone loess area of Hungary

    Science.gov (United States)

    Udvardi, Beatrix; Szabó, Zsuzsanna; Freiler, Ágnes; Kónya, Péter; Jerabek, Csaba; Pálfi, Éva; Kovács, István; Nagy, Péter; Halupka, Gábor

    2017-04-01

    It is well known that water from precipitation or other sources (e.g. groundwater, river) contributes to the triggering of landslides by means of infiltration into the slope, which causes an increase in the pore pressure and a reduction in the strength of the involved material. The physical failure is commonly coupled with chemical changes in landslides due the fact that soluble components dissolve in the pore water and others precipitate during rock-water interaction. Thus the composition of sediments and water chemistry are used jointly as indicators of the development of landslides. Rock-water interaction, however, takes a long time, and depends on hydrology and geochemistry of the landslide area; therefore, many researchers have focused on numerical simulation and laboratory experiment for setting up a landslide early warning system. Since water chemistry can change over time in landslides due to the seasonal rainfall pattern, groundwater fluctuation and flood events, the intensity of rock-water interaction (e.g. dissolution, precipitation) may also vary. Thus, the physicochemical processes cannot be elucidated precisely without understanding both the solution evolution and the mineral alteration in landslides. From this aspect, field survey, mineralogical (XRD, FTIR, DTG) and chemical measurements (ICP-OES), and geochemical modelling (PHREEQC) were conducted in a landslide-prone loess area along the River Danube (Hungary). Water from the River Danube and three springs were sampled during four field campaigns at Kulcs over a year. Additionally, landslide deposits including sliding surface and secondary precipitations were collected at Kulcs and Dunaújváros. In combination with previous hydrochemical analyses of the area and average rainfall composition of Hungary, it is possible to model the kinetic dissolution and precipitation of minerals during rainfall events and flooding periods of the river. The chemistry of springs shows that the Mg-Ca-HCO3 facies with

  10. Hydrogeological hazards and weather events: Triggering and evolution of shallow landslides

    Directory of Open Access Journals (Sweden)

    Salvatore Monteleone

    2014-06-01

    The complex nature of these instability events that affect anthropized areas does not allow specific approaches for the defence of single good, but it finds a more effective solution based on the extensive knowledge of territory, perhaps at the scale of individual or several watersheds.

  11. Submarine Landslides: What we Know and Where we are Going!

    Science.gov (United States)

    Moscardelli, L. G.; Mountjoy, J. J.; Micallef, A.; Strasser, M.; Vanneste, M.; Chaytor, J. D.; Mosher, D.; Krastel, S.; Lo Iacono, C.; Yamada, Y.

    2015-12-01

    Submarine landslides and other gravity-induced movements can disrupt very large areas of continental margins resulting in long-term seafloor morphologic change and multi-scale mass transport deposits (MTDs). Potential consequences of submarine landslides include damage to seabed infrastructure, offshore facilities, as well as generation or enhancement of tsunamis. MTDs are common on the modern seafloor and within the stratigraphic record. Slides, slumps and debris flows can be constituents of MTDs and can co-occur in the same event or depositional unit. Recent research indicates that relationships exist between MTD geological setting, causal mechanisms, and geometries. Quantitative data analysis suggests that MTD morphometric parameters can be used to link these three parameters. Despite many advances in this field, it still remains unclear how to definitively identify pre-conditioning factors and triggers of submarine landslides in modern slopes, and how submarine landslides evolve after initiation. In addition, new questions regarding the interaction between submarine landslides and active marine processes, such as bottom currents and fluid flow, have emerged.One of the mandates of the S4SLIDE (IGCP-640) project, a joint endeavor of UNESCO and IGCP that represents the broad field of submarine landslide research, is to facilitate interactions at an international level among scientists, industry and government representatives to advance our knowledge on a number of outstanding science questions: (i) What is the nature of the interaction between current-controlled sedimentation and submarine landslides? (ii) What role do transient turbulent-laminar flows play in the formation of submarine landslides? (iii) Do climatic variations control the occurrence of submarine landslides? (iv) What is the economic significance of submarine landslides? (v) Do we understand the hazards that submarine landslides pose to the environment and to humans? This presentation will cover

  12. Reservoir-induced landslides and risk control in Three Gorges Project on Yangtze River, China

    Directory of Open Access Journals (Sweden)

    Yueping Yin

    2016-10-01

    Full Text Available The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR. After construction of the TGR, the water level was raised from 70 m to 175 m above sea level (ASL, and annual reservoir regulation has caused a 30-m water level difference after impoundment of the TGR since September 2008. This paper first presents the spatiotemporal distribution of landslides in six periods of 175 m ASL trial impoundments from 2008 to 2014. The results show that the number of landslides sharply decreased from 273 at the initial stage to less than ten at the second stage of impoundment. Based on this, the reservoir-induced landslides in the TGR region can be roughly classified into five failure patterns, i.e. accumulation landslide, dip-slope landslide, reversed bedding landslide, rockfall, and karst breccia landslide. The accumulation landslides and dip-slope landslides account for more than 90%. Taking the Shuping accumulation landslide (a sliding mass volume of 20.7 × 106 m3 in Zigui County and the Outang dip-slope landslide (a sliding mass volume of about 90 × 106 m3 in Fengjie County as two typical cases, the mechanisms of reactivation of the two landslides are analyzed. The monitoring data and factor of safety (FOS calculation show that the accumulation landslide is dominated by water level variation in the reservoir as most part of the mass body is under 175 m ASL, and the dip-slope landslide is controlled by the coupling effect of reservoir water level variation and precipitation as an extensive recharge area of rainfall from the rear and the front mass is below 175 m ASL. The characteristics of landslide-induced impulsive wave hazards after and before reservoir impoundment are studied, and the probability of occurrence of a landslide-induced impulsive wave hazard has increased in the reservoir region. Simulation results of the Ganjingzi landslide in Wushan County indicate the

  13. Reservoir-induced landslides and risk control in Three Gorges Project on Yangtze River, China

    Institute of Scientific and Technical Information of China (English)

    Yueping Yin; Bolin Huang; Wenpei Wang; Yunjie Wei; Xiaohan Ma; Fei Ma; Changjun Zhao

    2016-01-01

    The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR). After construction of the TGR, the water level was raised from 70 m to 175 m above sea level (ASL), and annual reservoir regulation has caused a 30-m water level difference after impoundment of the TGR since September 2008. This paper first presents the spatiotemporal distribu-tion of landslides in six periods of 175 m ASL trial impoundments from 2008 to 2014. The results show that the number of landslides sharply decreased from 273 at the initial stage to less than ten at the second stage of impoundment. Based on this, the reservoir-induced landslides in the TGR region can be roughly classified into five failure patterns, i.e. accumulation landslide, dip-slope landslide, reversed bedding landslide, rockfall, and karst breccia landslide. The accumulation landslides and dip-slope landslides account for more than 90%. Taking the Shuping accumulation landslide (a sliding mass vol-ume of 20.7 × 106 m3) in Zigui County and the Outang dip-slope landslide (a sliding mass volume of about 90 × 106 m3) in Fengjie County as two typical cases, the mechanisms of reactivation of the two landslides are analyzed. The monitoring data and factor of safety (FOS) calculation show that the accumulation landslide is dominated by water level variation in the reservoir as most part of the mass body is under 175 m ASL, and the dip-slope landslide is controlled by the coupling effect of reservoir water level variation and precipitation as an extensive recharge area of rainfall from the rear and the front mass is below 175 m ASL. The characteristics of landslide-induced impulsive wave hazards after and before reservoir impoundment are studied, and the probability of occurrence of a landslide-induced impulsive wave hazard has increased in the reservoir region. Simulation results of the Ganjingzi land-slide in Wushan County indicate the strong relationship between

  14. Preliminary Assessment of Landslides Along the Florida River Downstream from Lemon Reservoir, La Plata County, Colorado

    Science.gov (United States)

    Schulz, William H.; Coe, Jeffrey A.; Ellis, William L.; Kibler, John D.

    2006-01-01

    resulted in increased ground-water pressures, which may have triggered the older landslide. This landslide appears to have crossed the valley floor and been subsequently eroded from this area. We found no evidence that landslide debris across the valley floor formed an impoundment of the Florida River, although it is very likely. Erosion of buttressing landslide debris from the valley floor and the lower strength of the landslide basal shear zone relative to pre-slide strength created less stable conditions than were present prior to occurrence of the landslide. However, deep ground-water conditions largely control the stability of the slope and are unknown here; hence, the potential for future deep landsliding is unknown. Additional investigation could be undertaken to further characterize landslide hazards in the area. This investigation could include episodic surveying of monuments we installed across the older landslide, obtaining detailed topographic data and aerial photography, mapping landslide debris and lacustrine deposits related to the potential former landslide dam, mapping secondary landslides, obtaining additional ages of landslide activity, constructing deep boreholes and ground-water monitoring wells, laboratory testing of soil and rock strength and hydraulic properties, and ground-water and slope-stability modeling.

  15. Landslides and fortified settlements as valuable geoheritage sites in the Moldavian Plateau, North-Eastern Romania

    Science.gov (United States)

    Niculita, Mihai; Bucci, Francesco; Santangelo, Michele; Ciprian Margarint, Mihai

    2016-04-01

    Landslides are widespread natural phenomena that shape the earth surface. As such, they are part of the environment where people live, playing an important role as natural hazard, but also making a place peculiar for its specific morphology. Nowadays, like in the past, people living in hilly to mountainous areas have always had to face landslides. In the Eastern Carpathians lowlands, landslides have carved a landscape with inaccessible escarpments tens of meters high, providing old populations with panoramic and naturally defensive places to build their settlements. This interaction produced an association of landslide morphologies and archaeological remains that is unique in Romaina. In this study, we present the case of chalcolitic and thraco-getic (6.5 ka BP to 500 BP) fortified settlements, for which landslides provided a favorable place for their construction on one hand, and acted as a natural hazard on the other hand. In the Moldavian Plateau, North-Eastern Romania, more than 50 sites were identified on structural plateaus bounded by wide scarps of Pleistocene landslides, on cuesta ridges bounded by scarps of Holocene landslides, or situated on hillslopes, on erosional remnants of landslide bodies. For nine out of the 50 sites, we produced accurate geomorphological landslide inventories, mapping more than 500 landslides starting from high resolution LiDAR DEM derived images. Such inventories provide information on landslide type and relative ages (very old, old, recent landslides) based on the morphological appearance of each slope failure. Analysis of the relations between the sites hosting the fortified settlements, their archaeological remains and very old landslides distribution, provides evidences that landslide scarps and their deposits were used by these populations as defensive sites. In particular, the scarps were used as natural walls, allowing to save material and manpower required to erect walls on the gentle and open parts of the sites. Besides

  16. The third hans cloos lecture. Urban landslides: Socioeconomic impacts and overview of mitigative strategies

    Science.gov (United States)

    Schuster, R.L.; Highland, L.M.

    2007-01-01

    As a result of population pressures, hillsides in the world's urban areas are being developed at an accelerating rate. This development increases the risk for urban landslides triggered by rainfall or earthquake activity. To counter this risk, four approaches have been employed by landslide managers and urban planners: (1) restricting development in landslide-prone areas; (2) implementing and enforcing excavation, grading, and construction codes; (3) protecting existing developments by physical mitigation measures and (4) developing and installing monitoring and warning systems. Where they have been utilized, these approaches generally have been effective in reducing the risk due to landslide hazards. In addition to these practices, landslide insurance holds promise as a mitigative measure by reducing the financial impact of landslides on individual property owners. Until recently, however, such insurance has not been widely available and, where it is available, it is so expensive that it has been little used. ?? Springer-Verlag 2006.

  17. Sediment Transportation Induced by Deep-Seated Landslides in a Debris Flow Basin in Taiwan

    Science.gov (United States)

    Lin, Meei Ling; Chen, Te Wei; Chen, Yong Sheng; Sin Jhuang, Han

    2016-04-01

    Typhoon Morakot brought huge amount of rainfall to the southern Taiwan in 2009 and caused severe landslides and debris flow hazard. After Typhoon Morakot, it was found that the volume of sediment transported by the debris flow and its effects on the affected area were much more significant compared to previous case history, which may due to the huge amount of rainfall causing significant deep-seated landslides in the basin. In this study, the effects and tendency of the sediment transportation in a river basin following deep-seated landslides caused by typhoon Morakot were evaluated. We used LiDAR, DEM, and aerial photo to identify characteristics of deep-seated landslides in a debris flow river basin, KSDF079 in Liuoguey District, Kaohsiung City, Taiwan. Eight deep-seated landslides were identified in the basin. To estimate the potential landslide volume associated with the deep-seated landslides, the stability analysis was conducted to locate the critical sliding surface, and the potential landside volume was estimated based on the estimation equation proposed by the International Geotechnical Societies' UNESCO Working Party on World Landslide Inventory (WP/WLI, 1990). The total potential landslide volume of the eight deep-seated landslides in KSDF079 basin was about 28,906,856 m3. Topographic analysis was performed by using DEM before and LiDAR derived DEM after typhoon Morakot to calculate the landslide volume transported. The result of erosion volume and deposition volume lead to a run out volume of 5,832,433 m3. The results appeared to consist well with the field condition and aerial photo. Comparing the potential landslide volume and run out volume of eight deep-seated landslides, it was found that the remaining potential landslide volume was about 80%. Field investigation and topographic analysis of the KSDF079 debris flow revealed that a significant amount of sediment deposition remained in the river channel ranging from the middle to the downstream

  18. Response of the Laprak Landslide to the 2015 Nepal Earthquake and Implications for the Utility of Simple Infinite Slope Models in Regional Landslide Hazard Assessment

    Science.gov (United States)

    Haneberg, W. C.; Gurung, N.

    2016-12-01

    The village of Laprak, located in the Gorkha District of western Nepal, was built on a large colluvium landslide about 10 km from the epicenter of the 25 April 2015 M 7.8 Nepal earthquake. Recent episodic movement began during a wet period in 1999 and continued in at least 2002, 2006, and 2007, destroying 24 homes, removing 23 hectares of land from agricultural production, and claiming 1 life. Reconnaissance mapping, soil sampling and testing, and slope stability analyses undertaken before the 2015 earthquake suggested that the hillside should be stable under dry conditions, unstable to marginally stable under static wet conditions, and wholly unstable under wet seismic conditions. Most of the buildings in Laprak, which were predominantly of dry fitted stone masonry, were destroyed by Intensity IX shaking during the 2015 earthquake. Interpretation of remotely sensed imagery and published photographs shows new landslide features; hence, some downslope movement occurred but the landslide did not mobilize into a long run-out flow. Monte Carlo simulations based upon a pseudostatic infinite slope model and constrained by reasonable distributions of soil shear strength, pore pressure, and slope angle from earlier work and seismic coefficients based upon the observed Intensity IX shaking (and inferred PGA) yield high probabilities of failure for steep portions of the slope above and below the village but moderate probabilities of failure for the more gentle portion of the slope upon which most of the village was constructed. In retrospect, the seismic coefficient selected for the pre-earthquake analysis proved to be remarkably prescient. Similar results were obtained using a first-order, second-moment (FOSM) approach that is convenient for GIS based regional analyses. Predictions of permanent displacement made using a variety of published empirical formulae based upon sliding block analyses range from about 10 cm to about 200 cm, also broadly consistent with the observed

  19. Landslide Susceptibility Assessment Through Fuzzy Logic Inference System (flis)

    Science.gov (United States)

    Bibi, T.; Gul, Y.; Rahman, A. Abdul; Riaz, M.

    2016-09-01

    Landslide is among one of the most important natural hazards that lead to modification of the environment. It is a regular feature of a rapidly growing district Mansehra, Pakistan. This caused extensive loss of life and property in the district located at the foothills of Himalaya. Keeping in view the situation it is concluded that besides structural approaches the non-structural approaches such as hazard and risk assessment maps are effective tools to reduce the intensity of damage. A landslide susceptibility map is base for engineering geologists and geomorphologists. However, it is not easy to produce a reliable susceptibility map due to complex nature of landslides. Since 1980s, several mathematical models have been developed to map landslide susceptibility and hazard. Among various models this paper is discussing the effectiveness of fuzzy logic approach for landslide susceptibility mapping in District Mansehra, Pakistan. The factor maps were modified as landslide susceptibility and fuzzy membership functions were assessed for each class. Likelihood ratios are obtained for each class of contributing factors by considering the expert opinion. The fuzzy operators are applied to generate landslide susceptibility maps. According to this map, 17% of the study area is classified as high susceptibility, 32% as moderate susceptibility, 51% as low susceptibility and areas. From the results it is found that the fuzzy model can integrate effectively with various spatial data for landslide hazard mapping, suggestions in this study are hope to be helpful to improve the applications including interpretation, and integration phases in order to obtain an accurate decision supporting layer.

  20. LANDSLIDE SUSCEPTIBILITY ASSESSMENT THROUGH FUZZY LOGIC INFERENCE SYSTEM (FLIS

    Directory of Open Access Journals (Sweden)

    T. Bibi

    2016-09-01

    Full Text Available Landslide is among one of the most important natural hazards that lead to modification of the environment. It is a regular feature of a rapidly growing district Mansehra, Pakistan. This caused extensive loss of life and property in the district located at the foothills of Himalaya. Keeping in view the situation it is concluded that besides structural approaches the non-structural approaches such as hazard and risk assessment maps are effective tools to reduce the intensity of damage. A landslide susceptibility map is base for engineering geologists and geomorphologists. However, it is not easy to produce a reliable susceptibility map due to complex nature of landslides. Since 1980s, several mathematical models have been developed to map landslide susceptibility and hazard. Among various models this paper is discussing the effectiveness of fuzzy logic approach for landslide susceptibility mapping in District Mansehra, Pakistan. The factor maps were modified as landslide susceptibility and fuzzy membership functions were assessed for each class. Likelihood ratios are obtained for each class of contributing factors by considering the expert opinion. The fuzzy operators are applied to generate landslide susceptibility maps. According to this map, 17% of the study area is classified as high susceptibility, 32% as moderate susceptibility, 51% as low susceptibility and areas. From the results it is found that the fuzzy model can integrate effectively with various spatial data for landslide hazard mapping, suggestions in this study are hope to be helpful to improve the applications including interpretation, and integration phases in order to obtain an accurate decision supporting layer.

  1. A study on the vegetation succession of pioneer trees in landslide control areas

    Science.gov (United States)

    Lee, J. H.; Lin, S. H.

    2015-12-01

    Located in subtropics, the steep terrain, concentrated rainy season, natural disaster, and artificial development have damaged the surface vegetation and resulted in soil loss and landslide in Taiwan. The control of landslide should stabilize the side slope as the priority. Furthermore, a proper engineering is applied to grow plants for the rapid forestation on landslide. Taking the location which has been done hydroseeding in the Shihmen Reservoir watershed as the example, the vegetation succession within the 8 years after the hydroseeding is investigated in this study. The growth and decline of pioneer trees like Rhus javanica is particularly discussed the vegetation recovery role and function on landslide. The research result could provide reference for the planning and design of vegetation recovery.

  2. On the influence of temporal change on the validity of landslide susceptibility maps in an alpine catchment, Switzerland

    Science.gov (United States)

    Meusburger, K.; Alewell, C.

    2009-04-01

    Global change (as a combination of climate and land use change) poses a risk to stability of alpine soils, and may enhance landslide hazard. The occurrence of landslides depends on static catchment characteristics (e.g. geology, topography etc.), as well as triggering factors that are variable in time (dynamic factors), such as event characteristics and land use. However, in literature the effects of temporal change are still discussed controversially and most statistical landslide prediction models rely on static catchment characteristics alone. In this study, we aim to assess the additional influence of dynamic factors on landslide susceptibility and on the validity of commonly used statistical landslide models. The Urseren Valley (Central Swiss Alps) was chosen as study area due to the evidence of climate and land use change. To assess the influence of catchment characteristics on landslide susceptibility, we set up a logistic regression model using 20 static predictor variables. The additional impact of dynamic risk factors was evaluated with historic data (aerial photographs and meteorological time series). We found that geology, slope and stream density were the most significant static predictors and could explain 70% of the landslide variation. However, the area affected by landslides increased by 92% from 1959 to 2004, which highlights the crucial role of dynamic landslide triggering factors. Furthermore, more recent landslides (since 2000) could only in part be predicted, which confirmed our proposed hypothesis that the validity of statistical hazard models may worsen over time. Discrepancies between predicted susceptibility and observed landslides mainly occurred in areas that have undergone land use changes. Consequently, slopes, that have formerly been classified as only "medium" landslide susceptibility may nonetheless have a high probability to fail under changed management. Spatial information of the impact of land use on landslide susceptibility

  3. 利用光学遥感数据、GIS及人工神经网络模型分析区域滑坡灾害%UTILIZATION OF OPTICAL REMOTE SENSING DATA AND GIS TOOLS FOR REGIONAL LANDSLIDE HAZARD ANALYSIS USING AN ARTIFICIAL NEURAL NETWORK MODEL

    Institute of Scientific and Technical Information of China (English)

    Biswajeet Pradhan; Saro Lee

    2007-01-01

    用光学遥感数据和地理信息系统(GIS)分析了马来西亚Selangor地区的滑坡灾害.通过遥感图像解译和野外调查,在研究区内确定出滑坡发生区.通过GIS和图像处理,建立了一个集地形、地质和遥感图像等多种信息的空间数据库.滑坡发生的因素主要为:地形坡度、地形方位、地形曲率及与排水设备距离;岩性及与线性构造距离;TM图像解译得到的植被覆盖情况;Landsat图像解译得到的植被指数;降水量.通过建立人工神经网络模型对这些因素进行分析后得到滑坡灾害图:由反向传播训练方法确定每个因素的权重值,然后用该权重值计算出滑坡灾害指数,最后用GIS工具生成滑坡灾害图.用遥感解译和野外观测确定出的滑坡位置资料验证了滑坡灾害图,准确率为82.92%.结果表明推测的滑坡灾害图与滑坡实际发生区域足够吻合.%The aim of this study is to evaluate landslide hazard analysis at Selangor area, Malaysia using optical remote sensing data and a Geographic Information System (GIS). Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys. Topographical, geological data and satellite images were collected, processed and constructed into a spatial database using GIS and image processing. There are about 10 landslide occurrence factors that were selected as: topographic slope, topographic aspect, topographic curvature and distance from drainage; lithology and distance from lineament; land cover from TM satellite images; the vegetation index value from Landsat satellite images; precipitation data. These factors were analyzed using an advanced artificial neural network model to generate the landslide hazard map. Each factor's weight was determined by the back-propagation training method. Then the landslide hazard indices were calculated using the trained back-propagation weights, and finally the landslide hazard map was

  4. Risk Mapping and Spatial Pattern of Debris Flow and Landslide Hazards in China%中国泥石流滑坡灾害风险制图与空间格局研究

    Institute of Scientific and Technical Information of China (English)

    刘希林; 余承君; 尚志海

    2011-01-01

    The paper studied the hazardousness, vulnerability and risk of debris flow and landslide in China and compiled maps with a scale of 1:6000000, based on Geographical Information Systems ( GIS ) technology, hazard zonation map, socioeconomic data from 2000. Integrated hazardousness of debris flow and landslide was the sum of debris flow hazardousness and landslide hazardousness. Vulnerability was employed a simplified assessing model, which was related to three aspects of GDP,land-use and population. Risk was expressed by the product of hazardousness and vulnerability. Analysis for the results of hazardousness,vulnerability and risk shows that China has extremely high risk territory with 104km2 occupied by debris flow and landslide hazards, and high risk territory with 283008km2, moderate risk territory with 3161815km2, low risk territory with 3299604km2, extremely low risk territory with 2681709km2,which respectively account for 0. 001% ,3% ,33. 55% ,35% , and 28. 45% of total territorial areas. The risk pattern of debris flow and landslide hazards had been studied, including the spatial patterns analyses of risk classes for 30 provinces and provincial capital cites. The studies suggest that the governments and land-use makers should carry out more strict politics for land uses. In the extremely high risk territory and in high risk regions, human activities and developments should be prohibited, and in the moderate risk areas, socioeconomic developments should be restricted so as to avoid the debris flow and landslide hazards.%基于GIS技术和危险性区划图、2000年的社会经济数据相关资料,研究了中国泥石流滑坡灾害危险度、易损度和风险度的量化与分析,分别编制了比例尺为1∶6000000的相应地图.泥石流滑坡灾害的危险度是泥石流危险度和滑坡危险度的叠加;易损度采用简化后的评估模型,模型输入指标包括国内生产总值、土地利用现状及人口分布3方面;风险度在

  5. Geologic factors contributing to landslide generation in a pyroclastic area: August 1998 Nishigo Village, Japan

    Science.gov (United States)

    Chigira, Masahiro

    2002-07-01

    Vertical contrasts in permeability, particularly where permeable surface materials overlie impermeable materials that prohibit the downward infiltration of groundwater, concentrate the groundwater and become an important focus of landslides that are triggered by intense rainfall. Just such a hydrogeological structure is present within the pyroclastics in Nishigo Village in Fukushima Prefecture, Japan, where intense rainfall of 1200 mm in 6 days generated more than 1000 landslides in August 1998. Three types of landslides occurred. The first type occurred along the edges of small plateaus, where horizontal beds of permeable ash, scoria, and pumice overlie impermeable mudflow deposits consisting of tuffaceous fines and andesite blocks, and massive, weakly consolidated ignimbrites. The rainfall on the plateaus infiltrated downward first, then laterally within the permeable beds, finally gushing out at the plateau edges and triggering landslides. The second type of landslide occurred where weathered tuff of the same ignimbrite was present with a slip surface at the base of the heavily weathered zone. Within this heavily weathered zone, the tuff exfoliated into thin weak plates running parallel to the slope surface. The third type of landslide involved failure of colluvium or ash that filled hollows. This type occurred as a result of subsurface erosion caused by the groundwater infiltrating the superficial beds above the impermeable tuff.

  6. 24 CFR 3285.406 - Flood hazard areas.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Flood hazard areas. 3285.406 Section 3285.406 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Anchorage Against Wind § 3285.406...

  7. 24 CFR 3285.302 - Flood hazard areas.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Flood hazard areas. 3285.302 Section 3285.302 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.302 Flood...

  8. Landslide risk models for decision making.

    Science.gov (United States)

    Bonachea, Jaime; Remondo, Juan; de Terán, José Ramón Díaz; González-Díez, Alberto; Cendrero, Antonio

    2009-11-01

    This contribution presents a quantitative