Dimmuborgir is thought to be a former rootless shield volcano, which was fed with lava from a nearby crater row, 2170 ± 38 calendar years before present. In this study, the orientation of striations on the sides of lava channels, collapse structures and lava pillars were measured to find out how the enigmatic ~2 km by 2 km volcanic structure at Dimmuborgir was drained. During one week of field work 149 striations were found and measured, with respect to their dip angle, dip direction and elevation. Their locations were recorded with a GPS (Global Positioning System) receiver. The orientations of the striations were visualized on Google Earth satellite images and on images from a Digital Terrain Model (DTM) of Dimmuborgir. Resulting visualizations show that Dimmuborgir was drained radially and in multiple stages. It is concluded that Dimmuborgir was drained towards the west, the northeast and the southeast. The drainage towards the west was channeled. The drainage towards the northeast and the southeast was radially inwards, towards the collapsed parts of Dimmuborgir.

Geografinei informacijai apie erdvinį žemės paviršių kaupti pastaruoju metu vis dažniau naudojamas vietovės skenavimo lazeriu iš orlaivio metodas LIDAR (Light Detection and Ranging). Šiuo metodu gaunama nereguliari taškinė labai tanki trijų dimensijų žemės paviršiaus objektų išsidėstymą sumodeliuojanti geometrinė ir radiometrinė informacija. Tai gana neseniai atsiradęs būdas, naudojamas žemės topografijos duomenims užrašyti, kuris Lietuvoje dar tik pradedamas naudoti. Dėl to naudinga ištirti šio metodo patikimumą, palyginant su įprastais duomenų surinkimo metodais (GPS), ir įvertinti šio metodo panaudojimo galimybes. Darbe nagrinėjama nuotolinių tyrimų metodais (LIDAR) gautų duomenų patikimumo problema. Tyrimo tikslas – nustatyti įvairiais metodais gautų reljefo aukščių duomenų patikimumą, analizuojant Riešės upelio baseino reljefą. Tyrimo eigoje buvo surinkti įvairiais metodais gauti Riešės upelio baseino reljefo duomenys; atlikti natūriniai matavimai pasirinktuose kontroliniuose ploteliuose, naudojantis geodeziniais instrumentais; pagal nuotolinių tyrimų gautus rezultatus sudarytas skaitmeninis reljefo modelis ir įvertintas jų tikslumas. Darbe palyginus natūrinių matavimų ir nuotolinių tyrimų metodais gautus rezultatus įrodyta, jog nuotoliniais tyrimų metodais gauti duomenys yra patikimi ir juos galima naudoti baseino tūriui ir plotui skaičiuoti. / LIDAR terrain laser scanning technique is increasingly used in digital terrain model creation. This method provides dense uneven three-dimensional scatter geometric and radiometric information that simulates objects on earth’s surface. This is a relatively recent method used to record topographic data of the land. One of the key issues still associated with remote sensing methods is its reliability, which is why it is relevant to analyze and evaluate this aspect. This thesis aims at evaluating LIDAR data reliability, comparing them with data obtained by field measurements carried out at selected control areas using geodesic instruments. Riešės river basin area was selected as an object for the study and its elevation data have been investigated in the research. It was concluded that LIDAR data are reliable and can be used for the basin volume calculation. However, the size of the grid should be selected according to terrain relief.

The aim of the thesis is localization and interpretation of paths of concentration runoff in digital terrain model. Digital terrain model(DTM) is processed for the catchment of the Jenín stream, where The Faculty of Agriculture has held the research since the year 2004. For creation of DTM following software programs were used for comparison: Erdas and ArcGIS. Digitalized maps of contour lines for this catchment were the backgrounds for creation of the DTM. Localization of paths of concentration runoff and natural thalwegs was made on created DTM. Then was the comparison of models and the real topography of the catchment realized. Possible reasons of differences were discussed in discussion. Different (in colours and resolution) variations of DTM with localized paths of concentration runoff are the result, with the view of better legibility and more truly representation of real topography of the landscape.

The central theme of my dissertation is the introduction to the creation of a digital terrain model in the area of recultivation of Chabarovice former softcoal strip mine near Usti nad Labem, especially it deals with land slide area Rabenov. This area is monitored using geodetic and geotechnical methods since 2003 to declare the area to be stable which would allow its full planned utilization. This thesis is a part of the terrestrial and satellite measurements for staged, performed within the project MSM. As input data were used points located by Topcon total station TCN 2006. The aim of my dissertation is to create a digital terrain model of a large scale using the program DMT Atlas.

Airborne Light Detection and Ranging (LIDAR) technology has become the primary method to derive high-resolution Digital Terrain Models (DTMs), which are essential for studying Earth’s surface processes, such as flooding and landslides. The critical step in generating a DTM is to separate ground and non-ground measurements in a voluminous point LIDAR dataset, using a filter, because the DTM is created by interpolating ground points. As one of widely used filtering methods, the progressive morphological (PM) filter has the advantages of classifying the LIDAR data at the point level, a linear computational complexity, and preserving the geometric shapes of terrain features. The filter works well in an urban setting with a gentle slope and a mixture of vegetation and buildings. However, the PM filter often removes ground measurements incorrectly at the topographic high area, along with large sizes of non-ground objects, because it uses a constant threshold slope, resulting in “cut-off” errors. A novel cluster analysis method was developed in this study and incorporated into the PM filter to prevent the removal of the ground measurements at topographic highs. Furthermore, to obtain the optimal filtering results for an area with undulating terrain, a trend analysis method was developed to adaptively estimate the slope-related thresholds of the PM filter based on changes of topographic slopes and the characteristics of non-terrain objects. The comparison of the PM and generalized adaptive PM (GAPM) filters for selected study areas indicates that the GAPM filter preserves the most “cut-off” points removed incorrectly by the PM filter. The application of the GAPM filter to seven ISPRS benchmark datasets shows that the GAPM filter reduces the filtering error by 20% on average, compared with the method used by the popular commercial software TerraScan. The combination of the cluster method, adaptive trend analysis, and the PM filter allows users without much experience in processing LIDAR data to effectively and efficiently identify ground measurements for the complex terrains in a large LIDAR data set. The GAPM filter is highly automatic and requires little human input. Therefore, it can significantly reduce the effort of manually processing voluminous LIDAR measurements.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the Geographic Information Systems platform, Digital Terrain Model (DTM) is a mathematical way, to show a natural feature that occurs in the Earth's surface. The purpose of this dissertation was to build a digital terrain model for the municipality of Graccho Cardoso, approximate scale 1:65.000, and analyze their products (contour map, slope map, shading map, and geological and geomorphological maps superimposed on the digital terrain model). The city of Graccho Cardoso is located in the north of the state of Sergipe, at about 120 km away from Aracaju. The study area was selected to present geomorphological and geological diversity and have Satellite Images (SRTM) with good resolution for the selected working range. Graccho Cardoso occurs in quotas ranging between 140 m and 280 m above sea level, where the predominant pattern dendritic drainage. Since its relief is under the process planing and pediplanation. Its steepness varies from 0% to over 75%. Where there is a predominance with the angle of inclination between 3 and 45%. It has been more remarkable shading which fit fluvial channels, showing that the notching index or grain dissection is more pronounced. It has two types of morphostructures: Remnants Fold Roots (Sergipano Orogenic System – Proterozoic) and Sedimentary Basins and Covers (Superficial Formations – Fanerozoic). The results obtained by integration of the various maps shows up very similar to many traditional data mapping surveys. / No ambiente dos Sistemas de Informações Geográficas, o Modelo Digital de Terreno (MDT) representa, de maneira matemática, uma feição natural que ocorre na superfície terrestre. A proposta dessa dissertação foi confeccionar um modelo digital de terreno para o município de Graccho Cardoso, na escala aproximada de 1:65.000, e analisar os seus produtos (mapa de curva de nível, mapa de declividade, modelo sombreado, mapa geomorfológico e mapa geológico sobrepostos ao modelo digital de terreno). O município de Graccho Cardoso está localizado na região norte do Estado de Sergipe, a cerca de 120 km de distância de Aracaju. A área de estudo foi selecionada por apresentar diversidade geomorfológica e geológica e, dispor de Imagens de Satélite (SRTM) com boa resolução para a escala de trabalho escolhida. A região de Graccho Cardoso ocorre em cotas variando entre de 140 m e 280 m de altitude, onde predomina o padrão de drenagem dendrítico. O seu relevo está sob o processo de aplainamento e pediplanação. Sua declividade varia entre 0 % a mais de 75 %. Onde existe um predomínio ondulado, o ângulo de inclinação varia entre 3 a 45%. Tem-se um sombreado mais marcante onde se encaixam os canais fluviais, mostrando que o índice de entalhamento, ou grau de dissecação, é mais acentuado. Possui dois tipos de morfoestruturas: Remanescentes de Raízes de Dobramentos (Sistema Orogênico Sergipano do Proterozóico) e, Bacias e Coberturas Sedimentares (Formações Superficiais do Fanerozóico). Os resultados obtidos pela integração dos diversos mapas mostram-se muitos similares com os dados tradicionais de levantamentos cartográficos.

The aim of my master’s thesis was to createa digital terrain model (DTM). The assigned data were to be processed, updated, unified and subsequently used to create a purpose map on the scale of 1:500. The selected area issituated near the village of Jedovnice; to be more specific, the area includes a meadow located along the Podomský rivulet and the adjacent forest. To create the purpose map, the MicroStation software was used (version V8). Furthermore, the Atlas DTM software (version 4)was used to create the digital terrain model, colour hypsometry and an exposure map and finally, the AutoCAD software (student version 2013) was used for visualizing and matching objects with textures.

La télédétection ouvre des perspectives nouvelles pour l’étude et la surveillance des volcans. Dans le cadre de cette thèse, différentes approches ont été abordées. L’imagerie satellite optique et thermique permet d’avoir une vue synoptique sur une large surface. La compréhension des changements d’état de surface est particulièrement importante dans le suivi de l’activité des volcans actifs. Plusieurs questions se posent : • Quels avantages offrent les satellites optiques d’observation de la Terre pour les calculs des volumes de lave émis ? • Quelles sont leurs limites ? • Les calculs de débits réalisés par télédétection sont-ils fiables ? • Quel est l’intérêt d’une approche multi-outils et multi-source ? Ces questions ont été abordées en prenant le Piton de la Fournaise pour cible. Plusieurs méthodes ont été mises en oeuvre et testées : 1) L’extraction automatique des contours de coulées de lave, 2) la création de modèle numérique d’élévation (MNE) par imagerie satellite, 3) le calcul de débits à partir d’images thermiques, 4) le suivi post éruptif d’une coulée par la modélisation de son refroidissement et la mesure des déformations observées in-situ. La plus-value de ce travail est la capacité de valider les résultats des modèles issus de la télédétection par des mesures in situ du fait de la proximité des sites étudiés. L’utilisation de ces techniques a permis d’obtenir des débits moyens d’écoulement des laves pour plusieurs éruptions et de suivre l’évolution topographique du volcan et de ses grandes structures. Les mesures thermiques par satellite fournissent le moyen de contraindre les variations du débit des éruptions dans le temps, tandis que les MNE ont permis d’obtenir un volume total dans le cas de coulées présentant de fortes épaisseurs. Grâce à ces techniques, il a été possible de définir deux types d’éruptions avec des évolutions semblables à celles observées sur différents volcans comme l’Etna (Italie) ou le Krafla (Islande). Les problèmes de nébulosité étant récurrent sur notre zone d’étude, la complémentarité des techniques est particulièrement intéressante pour obtenir une information fiable. Toutes les techniques utilisées dans cette thèse sont applicables à d’autres volcans ou à d’autres thématiques. / Remote sensing opens new perspectives for the study and monotoring of volcanoes. In this thesis, different approaches were discussed. optical and thermal satellite imagery provides a synoptic view over a wide area. The understanding of surface state changes is particulary important in the monotoring of the activity of active volcanoes. Several, questions arise: • What advantages offer optical observation satellites of the Earth for calculations of lava volumes issues? • What are their limits? • Calculations of flow by remote sensing are reliable? • What is the interest of a multi-tool and multi-source approach? These issues were addressed by taking the Piton de la Fournaise to target. Several methods have been implemented and tested: 1) automatic extraction of the contours of flows of lava, 2) the cretion of numerical model of elevation (DEM) imaging satellite, 3) the calculation of flows from thermal images, 4) follow-up post eruptive flow modelling of cooling and the observed deformations in-situ measurement. The added value of this work is the ability to validate the results of remote sensing measurements from models because of the proximity of the sites studied in situ. The use of these techniques to obtain the average flow rates of lavas to several eruptions and follow topographic evolution of the volcano and its large structures. Satellite thermal measurements provide the means of forcing changes in the flow of eruptions over time, while Dems helped to obtain a total volume in the case of flows with high thicknesses. With these techniques, it was possible to define two types of erutions with changes similar to those observed on different volcanoes.

Soil and terrain changes as a result of increased erosion and accumulation processes in selected locations Abstract Colluvial soils are formed in areas with increased intensity of soil erosion. Colluvial soils originate as a result of their position in terrain, they are usually found in places where has accumulated erosion material. Very often they are to be found at the around of slopes. Their accumulation horizon is deeper than 25 cm with a great amount of organic carbon buried in it. In my diploma thesis I will attempt to take a closer look at three locations, each having different types of dominant soils. The aim of this diploma thesis is to rebuild the original shape of the terrain before the beginning of the soil erosion process. Keywords: colluvial soil, soil erosion, soil accumulation, land use, digital terrain model (DTM)

Terrain Breakline Detection Using Sky-view factor Abstract The subject of this diploma thesis is to propose the procedure of detecting of terrain breaklines using Sky-view factor. The theoretical part of the diploma thesis first introduces the issue of terrain breaklines detection, which presents the methods known to date and Sky- view factor, which is the focal point of the proposed method. Implementation over real data takes place at four locations in the Czechia (Vítkovice, Hradiště, Strnady and Velenka). Data in the form of raster format is tested. At the end, the results of the proposed method and its verification using two selected methods of field edge detection are presented and evaluated. Achieved results point to Sky-view factor for terrain edge detection. Keywords: terrain breakline, digital terrain model, Sky-view factor, detection terrain breaklines methods