完善的崩塌地資料庫有助於地區土地利用的適宜性評估、與環境保護措施之研訂。目前，崩塌地地理空間資料(Geospatial data)的產生方法主要為：人為判釋經正射糾正(Ortho-rectification)的遙測影像，基於該影像，將辨識目標數位化(Digitizing)。然而，遙測影像的「正射糾正」與「人為判釋」往往不敷災後的緊急需求。為促進資料收集效率，本研究試圖發展一套自動化流程：以「未經糾正的遙測影像」為判釋對象，判釋作業以「物件式影像分類(Object-based classification)技術」進行，並利用「現存地形資料」，實現自動判釋所產生之辨識成果的地理對位(Georeferencing)與過濾篩選；最後，以「與現存各類輔助資料的套疊分析成果」為其屬性，以便利崩塌地地理空間資料的後續應用。 物件式影像分類分為為「影像分割(Image segmentation)」與「物件分類」兩步驟。於影像分割階段，採用多重解析度分割法(Multiresolution segmentation algorithm)─由於陰影下各類地物的影像光譜差異較不明顯，為避免陰影區之錯誤分割，賦予陰影區較小的尺度參數(Scale parameter)；於物件分類階段，基於訓練資料，以「線性核函數的支持向量機(Support Vector Machine, SVM, with a linear kernel)」為分類器，偵測「非雲與植被區」，並輸出為向量式資料(Vector data)。而後基於現存地形資料，以光線追蹤法(Ray-tracing algorithm)進行分類器輸出向量式資料的地理對位，並自訂第二階段的地形特徵過濾準則。實驗成果顯示，此自動化流程產出的崩塌地地理空間資料─其生產者精度(Producer’s accuracy)與使用者精度(User’s accuracy)分別介於0.85~0.99與0.44~0.96。

Se presenta un procedimiento para evaluar de forma cuantitativa el riesgo por deslizamientos teniendo en cuenta la peligrosidad, los elementos expuestos y su vulnerabilidad. El método utiliza los modelos de susceptibilidad obtenidos previamente a partir de las relaciones estadísticas existentes entre los deslizamientos ocurridos en el pasado (últimos 50 años) y una serie de parámetros del terreno relacionados con la inestabilidad. La frecuencia de deslizamientos en el pasado se ha utilizado para estimar frecuencias futuras. También se ha realizado un inventario y cartografía de los elementos afectados por deslizamientos en el pasado, y se han estimado los daños para cada tipo de elemento teniendo en cuenta la magnitud del tipo de deslizamiento analizado. Posteriormente se estimó la vulnerabilidad, que se expresa en valores de 0 a 1, a partir de la comparación entre pérdidas y valor del elemento afectado.La integración de la peligrosidad, vulnerabilidad y valor del elemento ha permitido obtener modelos de riesgo directo por deslizamiento para cada tipo de elemento. Además se han analizado las pérdidas indirectas ocasionadas sobre las actividades económicas por este proceso. El resultado final es un mapa de riesgo donde cada píxel muestra las pérdidas esperables por deslizamientos en los próximos 50 años / A quantitative procedure for landslide risk mapping has been developed considering hazard, vulnerability and exposed elements. The method is based on a susceptibility model previously developed from statistical relationships between past landslides occurred in the study area (last 50 years) and terrain parameters related to instability. Past landslide behaviour has been used to calculate landslide frequency for the future. An inventory of direct damage due to landslides during the study period was carried out and the main elements at risk in the area identified and mapped. Past monetary losses per type of element have been estimated and expressed as an average 'specific loss' for events of a given magnitude (corresponding to a specified scenario). Vulnerability has been assessed by comparing losses with the actual value of the elements affected and expressed as a fraction of that value (0-1).By integrating hazard, vulnerability and monetary value, direct landslide risk ( /pixel) has been computed for each element considered. Indirect losses from the disruption of economic activities due to landsliding have also been assessed. The final result is a risk map combining all losses per pixel for a 50-year period.

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The plate-boundary Alpine Fault runs immediately offshore of the popular tourist destination of Milford Sound, which is visited by more than half a million tourists each year. Glaciers retreated from the fiord between ~24-16 ka, leaving behind a legacy of extreme topography, including some of the world's highest sea cliffs, which tower nearly 2 km above the fiord. Visitors come to view the spectacularly steep and rugged landscape, with many cruising the fiord by boat. This project utilizes surface exposure dating (TCND) of glacially modified surfaces, to gain further insight into the glacier retreat history of Milford Sound. Exposure dates from strategic locations near the entrance to the fiord indicate that the main trunk glacier had retreated about 9 km from its peak LGM position by ~18 ka. Additional TCND and calibrated Schmidt Hammer data from a range of positions within the Milford catchment provide strong evidence that the main trunk glacier receded rapidly after about 18 ka, retreating a further 16 km to a position near the present-day confluence of the Tutoko and Cleddau rivers, by ~16 ka. Available seismic reflection data suggest that post-glacial sediment infill has been strongly influenced by massive deposits of rock avalanche debris. New high-resolution bathymetric and seismic reflection data reveals the presence of at least 18 very large post-glacial rock avalanche deposits which blanket ~40% of the fiord bottom. Geomorphic mapping and field investigation reveal the presence of at least ten additional very large to giant terrestrial landslide deposits in the lower Milford catchment; radiocarbon and surface exposure dating indicate that these events occurred during the Holocene, between ~9-1 ka. Ages of six of these deposits are in agreement with published rupture dates on the southern on-shore portion of the Alpine Fault.

Thesis (MSc)--Stellenbosch University, 2013. / Landslide susceptibility maps are important for development planning and disaster management. The current synthesis of landslide susceptibility maps largely applies GIS and remote sensing techniques. One of the most critical stages on landslide susceptibility mapping is the selection of landslide causative factors and weighting of the selected causative factors, in accordance to their influence to slope instability. GIS is ideal when deriving static factors i.e. slope and aspect and most importantly in the synthesis of landslide susceptibility maps. The integration of landslide causative thematic maps requires the selection of the weighting method; in order to weight the causative thematic maps in accordance to their influence to slope instability. Landslide susceptibility mapping is based on the assumption that future landslides will occur under similar circumstances as historic landslides. The weight of evidence method is ideal for landslide susceptibility mapping, as it calculates the weights of the causative thematic maps using known landslides points. This method was applied in an area within the Western Cape province of South Africa, the area is known to be highly susceptible to landslide occurrences. A prediction rate of 80.37% was achieved. The map combination approach was also applied and achieved a prediction rate of 50.98%. Satellite remote sensing techniques can be used to derive the thematic information needed to synthesize landslide susceptibility maps and to monitor the variable parameters influencing landslide susceptibility. Satellite remote sensing techniques can contribute to landslide investigation at three distinct phases namely: (1) detection and classification of landslides (2) monitoring landslide movement and identification of conditions leading up to an event (3) analysis and prediction of slope failures. Various sources of remote sensing data can contribute to these phases. Although the detection and classification of landslides through the remote sensing techniques is important to define landslide controlling parameters, the ideal is to use remote sensing data for monitoring of areas susceptible to landslide occurrence in an effort to provide an early warning. In this regard, optical remote sensing data was used successfully to monitor the variable conditions (vegetation health and productivity) that make an area susceptible to landslide occurrence.

This study demonstrates the value of historical aerial photographs as a source for monitoring long-term landslide evolution, which can be unlocked by using appropriate photogrammetric methods. The understanding of landslide mechanisms requires extensive data records; a literature review identified quantitative data on surface movements as a key element for their analysis. It is generally acknowledged that, owing to the flexibility and high degree of automation of modern digital photogrammetric techniques, it is possible to derive detailed quantitative data from aerial photographs. In spite of the relative ease of such techniques, there is only scarce research available on data quality that can be achieved using commonly available material, hence the motivation of this study. In two landslide case-studies (the Mam Tor and East Pentwyn landslides) the different types of products were explored, that can be derived from historical aerial photographs. These products comprised geomorphological maps, automatically derived elevation models (DEMs) and displacement vectors. They proved to be useful and sufficiently accurate for monitoring landslide evolution. Comparison with independent survey data showed good consistency, hence validating the techniques used. A wide range of imagery was used in terms of quality, media and format. Analysis of the combined datasets resulted in improvements to the stochastic model and establishment of a relationship between image ground resolution and data accuracy. Undetected systematic effects provided a limiting constraint to the accuracy of the derived data, but the datasets proved insufficient to quantify each factor individually. An important advancement in digital photogrammetry is image matching, which allows automation of various stages of the working chain. However, it appeared that the radiometric quality of historical images may not always assure good results, both for extracting DEMs and vectors using automatic methods. It can be concluded that the photographic archive can provide invaluable data for landslide studies, when modern photogrammetric techniques are being used. As ever, independent and appropriate checks should always be included in any photogrammetric design.

Ce travail est une analyse des conséquences de la présence de roches altérées, les altérites, sur les instabilités littorales du Labourd (Pays Basque). Le contexte environnemental des mouvements de terrain qui mobilisent ces matériaux méconnus est étudié afin de mieux appréhender les processus de rupture. Pour cela, d’une part, les altérites sont caractérisées d’un point de vue géologique ; d’autre part, les propriétés géotechniques et les circulations hydrogéologiques sont déterminées. Ces études permettent de mettre en évidence les différents facteurs prédisposant et déclenchant les instabilités, validés par modélisation numérique. La connaissance des processus ainsi améliorée, un outil d’estimation de l’aléa dans les altérites est proposé. / This work is an analysis of the consequences of the presence of weathered rocks, called alterites, on the coastal landslides of the Labourd (Basque country). The environmental context (geological, hydrogeological and morphological) of the landslides is studied to a better understanding of the failure processes. These studies allow to highlight the main triggering factors of the landslides, which are validated by numerical modelling. The knowledge of the processes so improved, a tool to estimate landslide hazards in the alterites is proposed.

Orientador: Geraldo de Freitas Maciel / Resumo: Esta pesquisa visa a investigação da funcionalidade pedagógica de revistas em quadrinhos e de jogos educativos como ferramenta educacional ensejadora da compreensão do nível de cultura dos desastres, com ênfase em deslizamento e inundação dada à sua recorrência no Brasil; a verificação da mesma eficácia pedagógica destas formas de linguagem é buscada no sentido de divulgar o direito dos desastres aqui vislumbrados por meio de políticas públicas capazes de minorar os efeitos gerados por desastres junto à população. Tendo como público alvo as crianças do ensino fundamental de escolas da rede de ensino pública e privada; a forma de aplicação da pesquisa se deu por meio do desenvolvimento de sequência didática que compreendeu a sensibilização para o assunto, a verificação de conhecimentos prévios, o oferecimento de novas informações e conceitos a partir dos saberes trazidos pelas crianças, a realização de atividades de fixação de conteúdo, o feedback, e a recompensa pela participação nas atividades e pelos resultados atingidos; e, apresentou conceitos, por meio de história em quadrinhos, e atividades, por meio de passatempos que foram elaborados de acordo com as teorias da Aprendizagem Mediada por Instrumentos e dde Desenvolvimento Proximal com o objetivo de verificar se tais atividades promoveriam, junto às crianças, aprendizagem significativa. Para resposta a este questionamento foram elencados três critérios sobre o do material: 1) Pertinência das Informações apresentadas no c... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This research aims to investigate the pedagogical functionality of comic books and educational games as an educational tool that promotes the understanding of the level of culture of disasters, with emphasis on sliding and flooding due to its recurrence in Brazil; the verification of the same pedagogical effectiveness of these forms of language is sought in the sense of divulging the right of the disasters here glimpsed through public policies able to reduce the effects generated by these with the population. Targeting the primary school children of public and private schools; the research was applied through the development of a didactic sequence that included awareness of the subject, the verification of previous knowledge, the provision of new information and concepts based on the knowledge brought by the children, the performance of attachment activities content, feedback, and reward for participation in activities and results achieved; and presented concepts through comics and activities through hobbies that were elaborated according to the theories of Instrumental Mediated Learning and the Zone of Proximal Development with the objective of verifying if such activities would promote, together with the children, meaningful learning. In response to this questioning, three criteria were listed about the material: 1) Relevance of the information presented in the content; 2) Adequacy of writing style; and 3) Ability to promote the association of ideas through illustrations. A... (Complete abstract click electronic access below) / Mestre

Natural hazards cause enormous amounts of damage worldwide every year. Since 1994 more than 1.35 billion people have lost their lives and more than 116 million homes have been damaged. Understanding of disaster risk implies knowledge about vulnerability, capacity, exposure of persons and assets, hazard characteristics and the environment. Quantitative damage assessments are a fundamental part of disaster risk management. There are, however, substantial challenges when quantifying damage which depends on the diversity of hazards and the fact that one hazardous event can negatively impact a society in multiple ways. The overall aim of the thesis is to analyze the relationship between climate-related natural hazards and subsequent damage for the purpose of improving the prerequisite for quantitative risk assessments in the future. The thesis concentrates on two specific types of consequences due to two types of hazards, 1) damage to buildings caused by lake floods, and 2) loss of lives caused by quick clay landslides.  Several causal relationships were established between risk factors and the extent of damages. Lake water levels increased the probability of structural building damage. Private damage reducing measures decreased the probability of structural building damage. Extent of damage decreased with distance to waterfront but increased with longer flood duration while prewar houses suffered lower flood damage compared to others. Concerning landslides, the number of fatalities increased when the number of humans in the exposed population increased. The main challenges to further damage estimation are data scarcity, insufficient detail level and the fact that the data are rarely systematically collected for scientific purposes. More efforts are needed to create structured, homogeneous and detailed damage databases with corresponding risk factors in order to further develop quantitative damage assessment of natural hazards in a Nordic perspective. / Naturolyckor orsakar enorma mängder skador över hela världen varje år. Under åren 1994-2013 förlorade mer än 1,35 miljoner människor sina liv och mer än 116 miljoner hem skadades. Förståelse av risk för naturolyckor innebär kunskap om sårbarhet, kapacitet, exponering av personer och tillgångar, hot och miljö. Kvantitativa skadebedömningar, som är en viktig del av riskbedömningar, omfattas av stora utmaningar som grundar sig i hotens mångfaldighet och det faktum att en naturolycka kan påverka ett samhälle negativt på många olika sätt. Det övergripande syftet med avhandlingen är att analysera förhållandet mellan naturkatastrofer och potentiellt påföljande skador i syfte att förbättra förutsättningarna för kvantitativa riskbedömningar i framtiden. Avhandlingen koncentrerar sig på två typer av naturolyckor med specifika konsekvenser, 1) skador på byggnader till följd av sjö-översvämningar, och 2) förlust av liv orsakat av lerskred. Flera orsakssamband mellan riskfaktorer och omfattning av skador har identifierats. Sjöarnas vattennivåer ökade sannolikheten att drabbas av strukturell byggnadsskada, samtidigt som privat initierade åtgärder minskande sannolikheten.. När avstånd mellan sjö och byggnad ökade minskade omfattningen av översvämningsskador, men ökade ju längre sjööversvämningen varade. Hus byggda före 1940 fick mindre skador jämfört med andra hus. Andelen dödsfall i samband med skred i kvicklera ökade när antal människor i den exponerade befolkningen ökade. Den största utmaningen i att förbättra dagens kvantitativa skadebedömningar är den rådande databristen vad gäller förluster och tillhörande riskfaktorer. Denna brist beror på otillgänglig skadedata, bristande detaljnivå på skadedata och tillhörande risk faktorer, och att uppgifterna sällan samlas systematiskt i syfte att studera kausalitet. / The overall aim of the thesis is to analyze the relationship between climate-related natural hazards and subsequent damage for the purpose of improving the prerequisite for quantitative risk assessments in the future. The thesis concentrates on two specific types of hazards with specific types of consequences, 1) damage to buildings caused by lake floods, and 2) loss of lives caused by quick clay landslides.  Several causal relationships were established between risk factors and the extent of damages. Lake water levels increased the probability of structural building damage. Private damage reducing measures decreased the probability of structural building damage. Extent of damage decreased with distance to waterfront but increased with longer flood duration while prewar houses suffered lower flood damage compared to others. Concerning landslides, the number of fatalities increased when the number of humans in the exposed population increased. The main challenges to further damage estimation are data scarcity, insufficient detail level and the fact that the data are rarely systematically collected for scientific purposes.

Neste trabalho foram integrados o mapeamento geológico de campo, os dados regionais aerogeofísicos e as imagens orbitais de alta resolução (1 m) para fornecer um mapa geológico detalhado do Pluton granítico Conselheiro Paulino, na Faixa Ribeira, Brasil. A área estudada possui poucos afloramentos e outras questões que dificultam o mapeamento geológico tradicional. Escorregamentos de terra são comuns na porção mais intemperizada do granito. A utilização de imagens orbitais de alta resolução permitiu a identificação dos poucos afloramentos existentes, além de outros elementos, como ravinas, planícies aluviais, eluviões, vegetação e estradas. Isso foi importante para orientar e otimizar as pesquisas de campo. A disponibilidade de dados aerogeofísicos magnéticos e radiométricos corroboraram nos trabalhos de campo e na petrografia do Pluton granítico Conselheiro Paulino. O pluton pode ser dividido em duas facies distintas, sendo uma de composição microgranítica e outra de composição microgranodiorítica / In the present work, we integrate field geological mapping, regional airborne geophysical data and high resolution (1 m) satellite images to provide a detailed geological map of the Conselheiro Paulino granitic pluton in the Ribeira Belt, Brazil. The studied area has few outcrops and other issues that limit the traditional geological mapping. Landslides are common in the highly weathered portion of the granite. The use of high-resolution images allowed the identification of the few available outcrops and other elements such as ravines, aluvial plains, eluvial deposits, vegetation and roads. This was important to guide and optimize the fieldwork surveys. The available magnetic and radiometric airborne geophysical data corroborate field and petrographic data about the Conselheiro Paulino granite pluton. The pluton can be divided into two distinct facies, one with microgranitic and the other with microgranodioritic composition.