938 resultados para Topographic maps


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This work aimed to apply geoprocessing techniques to identify and to quantify the types of vegetal coverings in part of the county Botucatu – SP, having been divided into three phases: acquisition of data; georeferencing based on the digital topographic maps in 1:50000 scale and finally the thematic maps were generated. The methodology used to the analogical aerial photographics georeferencing showed efficient, considering that it was based on scientific procedures of residues analysis and the positioning central was classified as A, according to the Cartographic Precision Pattern.

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The objective of this work was to evaluate the sediment production in the initial part of the Pardo River Basin - Botucatu/SP from 1994 to 1999, using the mathematical hydrological model SWAT. It was used topographic maps and satellite data manipulated in GIS using the software SPRING 5.1.6. The simulation of sediment production was generated with the aid of an interface between the hydrological model SWAT 2009 with ArcView ®, version 9.3. The maps of Soil, Land Use and Digital Elevation Model (DEM) were generated in the GIS-SPRING 5.1.6 and exported to ArcSWAT 2009. The tabular data related to the parameters of soil and meteorological parameters were entered directly to the SWAT. The model allowed to estimate the sediment production. A sediment average production rate of 33.866 ton ha-1 over the six years of study was computed in the point of discharge of the basin.

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The study of the hydro-physical behavior in soils using toposequences is of great importance for better understanding the soil, water and vegetation relationships. This study aims to assess the hydro-physical and morphological characterization of soil from a toposequence in Galia, state of São Paulo, Brazil). The plot covers an area of 10.24 ha (320 × 320 m), located in a semi-deciduous seasonal forest. Based on ultra-detailed soil and topographic maps of the area, a representative transect from the soil in the plot was chosen. Five profiles were opened for the morphological description of the soil horizons, and hydro-physical and micromorphological analyses were performed to characterize the soil. Arenic Haplustult, Arenic Haplustalf and Aquertic Haplustalf were the soil types observed in the plot. The superficial horizons had lower density and greater hydraulic conductivity, porosity and water retention in lower tensions than the deeper horizons. In the sub-superficial horizons, greater water retention at higher tensions and lower hydraulic conductivity were observed, due to structure type and greater clay content. The differences observed in the water retention curves between the sandy E and the clay B horizons were mainly due to the size distribution, shape and type of soil pores.

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Salt deposits characterize the subsurface of Tuzla (BiH) and made it famous since the ancient times. Archeological discoveries demonstrate the presence of a Neolithic pile-dwelling settlement related to the existence of saltwater springs that contributed to make the most of the area a swampy ground. Since the Roman times, the town is reported as “the City of Salt deposits and Springs”; "tuz" is the Turkish word for salt, as the Ottomans renamed the settlement in the 15th century following their conquest of the medieval Bosnia (Donia and Fine, 1994). Natural brine springs were located everywhere and salt has been evaporated by means of hot charcoals since pre-Roman times. The ancient use of salt was just a small exploitation compared to the massive salt production carried out during the 20th century by means of classical mine methodologies and especially wild brine pumping. In the past salt extraction was practised tapping natural brine springs, while the modern technique consists in about 100 boreholes with pumps tapped to the natural underground brine runs, at an average depth of 400-500 m. The mining operation changed the hydrogeological conditions enabling the downward flow of fresh water causing additional salt dissolution. This process induced severe ground subsidence during the last 60 years reaching up to 10 meters of sinking in the most affected area. Stress and strain of the overlying rocks induced the formation of numerous fractures over a conspicuous area (3 Km2). Consequently serious damages occurred to buildings and infrastructures such as water supply system, sewage networks and power lines. Downtown urban life was compromised by the destruction of more than 2000 buildings that collapsed or needed to be demolished causing the resettlement of about 15000 inhabitants (Tatić, 1979). Recently salt extraction activities have been strongly reduced, but the underground water system is returning to his natural conditions, threatening the flooding of the most collapsed area. During the last 60 years local government developed a monitoring system of the phenomenon, collecting several data about geodetic measurements, amount of brine pumped, piezometry, lithostratigraphy, extension of the salt body and geotechnical parameters. A database was created within a scientific cooperation between the municipality of Tuzla and the city of Rotterdam (D.O.O. Mining Institute Tuzla, 2000). The scientific investigation presented in this dissertation has been financially supported by a cooperation project between the Municipality of Tuzla, The University of Bologna (CIRSA) and the Province of Ravenna. The University of Tuzla (RGGF) gave an important scientific support in particular about the geological and hydrogeological features. Subsidence damage resulting from evaporite dissolution generates substantial losses throughout the world, but the causes are only well understood in a few areas (Gutierrez et al., 2008). The subject of this study is the collapsing phenomenon occurring in Tuzla area with the aim to identify and quantify the several factors involved in the system and their correlations. Tuzla subsidence phenomenon can be defined as geohazard, which represents the consequence of an adverse combination of geological processes and ground conditions precipitated by human activity with the potential to cause harm (Rosenbaum and Culshaw, 2003). Where an hazard induces a risk to a vulnerable element, a risk management process is required. The single factors involved in the subsidence of Tuzla can be considered as hazards. The final objective of this dissertation represents a preliminary risk assessment procedure and guidelines, developed in order to quantify the buildings vulnerability in relation to the overall geohazard that affect the town. The historical available database, never fully processed, have been analyzed by means of geographic information systems and mathematical interpolators (PART I). Modern geomatic applications have been implemented to deeply investigate the most relevant hazards (PART II). In order to monitor and quantify the actual subsidence rates, geodetic GPS technologies have been implemented and 4 survey campaigns have been carried out once a year. Subsidence related fractures system has been identified by means of field surveys and mathematical interpretations of the sinking surface, called curvature analysis. The comparison of mapped and predicted fractures leaded to a better comprehension of the problem. Results confirmed the reliability of fractures identification using curvature analysis applied to sinking data instead of topographic or seismic data. Urban changes evolution has been reconstructed analyzing topographic maps and satellite imageries, identifying the most damaged areas. This part of the investigation was very important for the quantification of buildings vulnerability.

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The thesis contributed to the volcanic hazard assessment through the reconstruction of some historical flank eruptions of Etna in order to obtain quantitative data (volumes, effusion rates, etc.) for characterizing the recent effusive activity, quantifying the impact on the territory and defining mitigation actions for reducing the volcanic risk as for example containment barriers. The reconstruction was based on a quantitative approach using data extracted from aerial photographs and topographic maps. The approach allows to obtain the temporal evolution of the lava flow field and estimating the Time Average Discharge Rate (TADR) by dividing the volume emplaced over a given time interval for the corresponding duration. The analysis concerned the 2001, 1981 and 1928 Etna eruptions. The choice of these events is linked to their impact on inhabited areas. The results of the analysis showed an extraordinarily high effusion rate for the 1981 and 1928 eruptions (over 600 m^3/s), unusual for Etna eruptions. For the 1981 Etna eruption an eruptive model was proposed to explain the high discharge rate. The obtained TADRs were used as input data for simulations of the propagation of the lava flows for evaluating different scenarios of volcanic hazard and analyse different mitigation actions against lava flow invasion. It was experienced how numerical simulations could be adopted for evaluating the effectiveness of barrier construction and for supporting their optimal design. In particular, the gabions were proposed as an improvement for the construction of barriers with respect to the earthen barriers. The gabion barriers allow to create easily modular structures reducing the handled volumes and the intervention time. For evaluating operational constrain an experimental test was carried out to test the filling of the gabions with volcanic rock and evaluating their deformation during transport and placement.

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In den letzten drei Jahrzehnten sind Fernerkundung und GIS in den Geowissenschaften zunehmend wichtiger geworden, um die konventionellen Methoden von Datensammlung und zur Herstellung von Landkarten zu verbessern. Die vorliegende Arbeit befasst sich mit der Anwendung von Fernerkundung und geographischen Informationssystemen (GIS) für geomorphologische Untersuchungen. Durch die Kombination beider Techniken ist es vor allem möglich geworden, geomorphologische Formen im Überblick und dennoch detailliert zu erfassen. Als Grundlagen werden in dieser Arbeit topographische und geologische Karten, Satellitenbilder und Klimadaten benutzt. Die Arbeit besteht aus 6 Kapiteln. Das erste Kapitel gibt einen allgemeinen Überblick über den Untersuchungsraum. Dieser umfasst folgende morphologische Einheiten, klimatischen Verhältnisse, insbesondere die Ariditätsindizes der Küsten- und Gebirgslandschaft sowie das Siedlungsmuster beschrieben. Kapitel 2 befasst sich mit der regionalen Geologie und Stratigraphie des Untersuchungsraumes. Es wird versucht, die Hauptformationen mit Hilfe von ETM-Satellitenbildern zu identifizieren. Angewandt werden hierzu folgende Methoden: Colour Band Composite, Image Rationing und die sog. überwachte Klassifikation. Kapitel 3 enthält eine Beschreibung der strukturell bedingten Oberflächenformen, um die Wechselwirkung zwischen Tektonik und geomorphologischen Prozessen aufzuklären. Es geht es um die vielfältigen Methoden, zum Beispiel das sog. Image Processing, um die im Gebirgskörper vorhandenen Lineamente einwandfrei zu deuten. Spezielle Filtermethoden werden angewandt, um die wichtigsten Lineamente zu kartieren. Kapitel 4 stellt den Versuch dar, mit Hilfe von aufbereiteten SRTM-Satellitenbildern eine automatisierte Erfassung des Gewässernetzes. Es wird ausführlich diskutiert, inwieweit bei diesen Arbeitsschritten die Qualität kleinmaßstäbiger SRTM-Satellitenbilder mit großmaßstäbigen topographischen Karten vergleichbar ist. Weiterhin werden hydrologische Parameter über eine qualitative und quantitative Analyse des Abflussregimes einzelner Wadis erfasst. Der Ursprung von Entwässerungssystemen wird auf der Basis geomorphologischer und geologischer Befunde interpretiert. Kapitel 5 befasst sich mit der Abschätzung der Gefahr episodischer Wadifluten. Die Wahrscheinlichkeit ihres jährlichen Auftretens bzw. des Auftretens starker Fluten im Abstand mehrerer Jahre wird in einer historischen Betrachtung bis 1921 zurückverfolgt. Die Bedeutung von Regentiefs, die sich über dem Roten Meer entwickeln, und die für eine Abflussbildung in Frage kommen, wird mit Hilfe der IDW-Methode (Inverse Distance Weighted) untersucht. Betrachtet werden außerdem weitere, regenbringende Wetterlagen mit Hilfe von Meteosat Infrarotbildern. Genauer betrachtet wird die Periode 1990-1997, in der kräftige, Wadifluten auslösende Regenfälle auftraten. Flutereignisse und Fluthöhe werden anhand von hydrographischen Daten (Pegelmessungen) ermittelt. Auch die Landnutzung und Siedlungsstruktur im Einzugsgebiet eines Wadis wird berücksichtigt. In Kapitel 6 geht es um die unterschiedlichen Küstenformen auf der Westseite des Roten Meeres zum Beispiel die Erosionsformen, Aufbauformen, untergetauchte Formen. Im abschließenden Teil geht es um die Stratigraphie und zeitliche Zuordnung von submarinen Terrassen auf Korallenriffen sowie den Vergleich mit anderen solcher Terrassen an der ägyptischen Rotmeerküste westlich und östlich der Sinai-Halbinsel.

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The arid regions are dominated to a much larger degree than humid regions by major catastrophic events. Although most of Egypt lies within the great hot desert belt; it experiences especially in the north some torrential rainfall, which causes flash floods all over Sinai Peninsula. Flash floods in hot deserts are characterized by high velocity and low duration with a sharp discharge peak. Large sediment loads may be carried by floods threatening fields and settlements in the wadis and even people who are living there. The extreme spottiness of rare heavy rainfall, well known to desert people everywhere, precludes any efficient forecasting. Thus, although the limitation of data still reflects pre-satellite methods, chances of developing a warning system for floods in the desert seem remote. The relatively short flood-to-peak interval, a characteristic of desert floods, presents an additional impediment to the efficient use of warning systems. The present thesis contains introduction and five chapters, chapter one points out the physical settings of the study area. There are the geological settings such as outcrop lithology of the study area and the deposits. The alluvial deposits of Wadi Moreikh had been analyzed using OSL dating to know deposits and palaeoclimatic conditions. The chapter points out as well the stratigraphy and the structure geology containing main faults and folds. In addition, it manifests the pesent climate conditions such as temperature, humidity, wind and evaporation. Besides, it presents type of soils and natural vegetation cover of the study area using unsupervised classification for ETM+ images. Chapter two points out the morphometric analysis of the main basins and their drainage network in the study area. It is divided into three parts: The first part manifests the morphometric analysis of the drainage networks which had been extracted from two main sources, topographic maps and DEM images. Basins and drainage networks are considered as major influencing factors on the flash floods; Most of elements were studied which affect the network such as stream order, bifurcation ratio, stream lengths, stream frequency, drainage density, and drainage patterns. The second part of this chapter shows the morphometric analysis of basins such as area, dimensions, shape and surface. Whereas, the third part points the morphometric analysis of alluvial fans which form most of El-Qaá plain. Chapter three manifests the surface runoff through rainfall and losses analysis. The main subject in this chapter is rainfall which has been studied in detail; it is the main reason for runoff. Therefore, all rainfall characteristics are regarded here such as rainfall types, distribution, rainfall intensity, duration, frequency, and the relationship between rainfall and runoff. While the second part of this chapter concerns with water losses estimation by evaporation and infiltration which are together the main losses with direct effect on the high of runoff. Finally, chapter three points out the factors influencing desert runoff and runoff generation mechanism. Chapter four is concerned with assessment of flood hazard, it is important to estimate runoff and tocreate a map of affected areas. Therefore, the chapter consists of four main parts; first part manifests the runoff estimation, the different methods to estimate runoff and its variables such as runoff coefficient lag time, time of concentration, runoff volume, and frequency analysis of flash flood. While the second part points out the extreme event analysis. The third part shows the map of affected areas for every basin and the flash floods degrees. In this point, it has been depending on the DEM to extract the drainage networks and to determine the main streams which are normally more dangerous than others. Finally, part four presets the risk zone map of total study area which is of high inerest for planning activities. Chapter five as the last chapter concerns with flash flood Hazard mitigation. It consists of three main parts. First flood prediction and the method which can be used to predict and forecast the flood. The second part aims to determine the best methods which can be helpful to mitigate flood hazard in the arid zone and especially the study area. Whereas, the third part points out the development perspective for the study area indicating the suitable places in El-Qaá plain for using in economic activities.

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This paper describes the procedures used to create a distributed collection of topographic maps of the Austro-Hungarian Empire, the Spezialkarte der Öesterriechisch-ungarnischen Monarchie, Masse. 1:75,000 der natur. This set of maps was published in Vienna over a period of years from 1877 to 1914. The part of the set used in this project includes 776 sheets; all sheets from all editions number over 3,665. The paper contains detailed information on how the maps were converted to digital images, how metadata were prepared, and how Web-browser access was created using ArcIMS Metadata Server. The project, funded by a 2004 National Leadership Grant from the Institute for Museums and Library Science (IMLS), was a joint project of the Homer Babbidge Library Map and Geographic Information Center at the University of Connecticut, the New York Public Library, and the American Geographical Society’s Map Library at the University of Wisconsin Milwaukee.

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Empresas como HEXA S.A. desean introducir SIG como elemento para incrementar el valor agregado de los proyectos de consultoría que realizan. Tal es el caso del trabajo encomendado por ellos al CIFOT titulado Esquema hidromorfológico de la cuenca del río Tunuyán Superior y clasificación de Usos del Suelo del Oasis Centro Oeste; Provincia de Mendoza. Se unifica en un único modelo digital una serie de cartas topográficas (IGM) digitalizan diversos niveles de información (curvas de nivel, hidrografía de la cuenca del río Tunuyán), red de caminos y su jerarquía. A partir de la base de datos lograda, se generan mapas temáticos de cada cuenca, apoyados con imágenes satelitales Landsat TM, que permiten identificar cobertura nivo- glacial y usos del suelo en el Oasis. Con esta información la empresa obtiene un modelo de simulación del Río Tunuyán para predecir el caudal que conduciría el río ante determinadas nevadas, por ejemplo. Se propone además un modelo de SIG para el monitoreo de la zona.

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Este artículo pretende exponer la influencia que las nuevas estrategias de organización territorial para la campaña bonaerense, materializadas durante la primera mitad del siglo XIX, pudieron ejercer sobre la estructura urbana y social de los pueblos de la región. Partimos del supuesto, desarrollado en otros trabajos, de que dichas estrategias definieron, en parte, la transformación espacial del territorio a partir de tres premisas: la consolidación de los poblados existentes, la fundación de nuevos poblados y el desarrollo de la colonización ejidal (1). Para poder examinar en profundidad dichas estrategias tomamos como base el análisis del espacio urbano de Chascomús y sus alrededores considerando dos momentos de su conformación: 1826 y 1855. Estas fechas se corresponden con la existencia de documentos que representan espacialmente el lugar: los planos de Saubidet de 1826 y el plano de Arrufó de 1855. A partir de estos documentos intentaremos determinar cuáles son las estrategias oficiales en relación a la organización espacial, cómo se materializa el poblado, qué tipo de entramado social presenta y cuáles son las diferencias que encontramos entre una época y otra, teniendo en consideración que la primera corresponde al inicio de la expansión de la frontera bonaerense y la segunda al auge de la etapa lanera que tiene en Chascomús uno de sus centros.

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Este artículo pretende exponer la influencia que las nuevas estrategias de organización territorial para la campaña bonaerense, materializadas durante la primera mitad del siglo XIX, pudieron ejercer sobre la estructura urbana y social de los pueblos de la región. Partimos del supuesto, desarrollado en otros trabajos, de que dichas estrategias definieron, en parte, la transformación espacial del territorio a partir de tres premisas: la consolidación de los poblados existentes, la fundación de nuevos poblados y el desarrollo de la colonización ejidal (1). Para poder examinar en profundidad dichas estrategias tomamos como base el análisis del espacio urbano de Chascomús y sus alrededores considerando dos momentos de su conformación: 1826 y 1855. Estas fechas se corresponden con la existencia de documentos que representan espacialmente el lugar: los planos de Saubidet de 1826 y el plano de Arrufó de 1855. A partir de estos documentos intentaremos determinar cuáles son las estrategias oficiales en relación a la organización espacial, cómo se materializa el poblado, qué tipo de entramado social presenta y cuáles son las diferencias que encontramos entre una época y otra, teniendo en consideración que la primera corresponde al inicio de la expansión de la frontera bonaerense y la segunda al auge de la etapa lanera que tiene en Chascomús uno de sus centros.

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Este artículo pretende exponer la influencia que las nuevas estrategias de organización territorial para la campaña bonaerense, materializadas durante la primera mitad del siglo XIX, pudieron ejercer sobre la estructura urbana y social de los pueblos de la región. Partimos del supuesto, desarrollado en otros trabajos, de que dichas estrategias definieron, en parte, la transformación espacial del territorio a partir de tres premisas: la consolidación de los poblados existentes, la fundación de nuevos poblados y el desarrollo de la colonización ejidal (1). Para poder examinar en profundidad dichas estrategias tomamos como base el análisis del espacio urbano de Chascomús y sus alrededores considerando dos momentos de su conformación: 1826 y 1855. Estas fechas se corresponden con la existencia de documentos que representan espacialmente el lugar: los planos de Saubidet de 1826 y el plano de Arrufó de 1855. A partir de estos documentos intentaremos determinar cuáles son las estrategias oficiales en relación a la organización espacial, cómo se materializa el poblado, qué tipo de entramado social presenta y cuáles son las diferencias que encontramos entre una época y otra, teniendo en consideración que la primera corresponde al inicio de la expansión de la frontera bonaerense y la segunda al auge de la etapa lanera que tiene en Chascomús uno de sus centros.

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A map of the tidal flats of China, Manchuria and Korea depicted in US Army Map Service Series L500, L542 and L552 topographic maps (compiled between 1950 and 1964). The topographic maps were georeferenced against prominent topographical features in L1T processed Landsat imagery and the foreshore flat class was manually delineated. For further information refer to Murray et. al. (2014).

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The Palestine Exploration Fund (PEF) Survey of Western Palestine (1871-1877) is highly praised for its accuracy and completeness; the first systematic analysis of its planimetric accuracy was published by Levin (2006). To study the potential of these 1:63,360 maps for a quantitative analysis of land cover changes over a period of time, Levin has compared them to 20th century topographic maps. The map registration error of the PEF maps was 74.4 m using 123 control points of trigonometrical stations and a 1st order polynomial. The median RMSE of all control and test points (n = 1104) was 153.6 m. Following the georeferencing of each of the 26 sheets of the PEF maps of the Survey of Western Palestine, a mosaicked file has been created. Care should be taken when analysing historical maps, as it cannot be assumed that their accuracy is consistent at different parts or for different features depicted on them.