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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Avaliação do potencial geotérmico da bacia sedimentar de Taubaté / Evaluation of Taubate basin geothermal

Souza Filho, Mário Nascimento, 1943- 20 August 2018 (has links)
Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-20T15:45:24Z (GMT). No. of bitstreams: 1 SouzaFilho_MarioNascimento_M.pdf: 8976577 bytes, checksum: 06f17de0e0e20fb1daea5a785d88c120 (MD5) Previous issue date: 2012 / Resumo: Os recursos conhecidos de energia geotermal no Brasil são de baixa entalpia, com fontes contendo fluidos com valores de temperatura inferiores a 100ºC. Isto por si só desencoraja a tentativa de buscar cenários possíveis de aproveitamento das fontes, restritas até então, aos usos através de balneários, com o aproveitamento dos poços mais profundos perfurados inicialmente para petróleo, principalmente na Bacia do Paraná. Estudos recentes foram desenvolvidos em diversos países com vistas ao aproveitamento geotermal de bacias sedimentares, semelhantes às nossas, buscando recursos geotermais, abaixo do topo do embasamento, nos denominados HDR (Hot Dry Rock), através de injeção de fluidos que irão circular no meio rochoso fraturado (artificialmente ou não), aquecer e retornar à superfície em forma de vapor, para então serem aproveitados. Este cenário foi avaliado e estudado para um eventual aproveitamento na Bacia de Taubaté. Uma pesquisa bibliográfica foi feita focada no tema em estudo e não pretendeu esgotar o assunto, mas sim servir de ponto de partida para realizá-los. Foram tratados os perfis geofísicos de 39 poços selecionados no vale do Paraíba do Sul, entre Jacareí e Cachoeira Paulista, no Estado de São Paulo, identificadas as alternâncias litológicas, medidas as temperaturas dos poços, em construção, as espessuras dos distintos litotipos e traçados mapas de isovalores do topo do embasamento cristalino e sua temperatura. A partir desse ponto calculou-se o grau geotérmico para a área e foram traçados mapas previsionais de temperatura no horizonte 1.000 metros de profundidade sobrepostos aos mapas temáticos da distribuição percentual dos litotipos encontrados na bacia, com vistas ao aproveitamento econômico dos recursos geotermais. Duas áreas no vale do Paraíba despertaram interesse e será objeto de novas prospecções com vistas à definição do Projeto de Avaliação de Energia Geotermal na Bacia de Taubaté / Abstract: The known geothermal energy resources of Brazil have a low enthalpy level, with sources showing temperature levels lower than 100º Centigrade This fact by itself had discouraged initiatives aimed to find possible scenarios for utilization of such sources, which had been employed insofar for recreational activities in water resorts by means of exploitation of deep wells drilled initially for oil and gas in Paraná Basin. Recent studies were developed several countries aiming at geothermal utilization of sedimentary basins, similar to the Brazilian ones, searching for geothermal resources named Hot Dry Rock (HDR), through injection of fluids that will circulate within rocky fault or fractured crystalline basement and return to the surface in form of vapor in order to be utilized. This scenario is being evaluated and hereto studied for potential utilization in Taubaté Basin. Bibliographic research was made focused in this subject studied and it does not aim to exhaust this subject but rather support such studies and become a starting point. Geophysical logs of 39, mainly water wells drilled in Paraíba do Sul Valley, between Jacareí and Cachoeira Paulista, were analyzed and different lithological beds were interpreted. Temperatures of wells in construction were measured, the thickness of distinguished litologies and a surface trend analysis maps were constructed. The target of this study is the evaluation of the crystalline basement top and its temperature. Throughout this point the study aims to calculate the geothermic grade for the area and evaluate the region potentiality taking into consideration the economic exploitation of the geothermal resources. Two areas in Paraíba Valley have attracted interest and will be subject to new prospections aiming the definition of the Project for Evaluation of Taubaté Basin Geothermal Energy / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências
232

Etude des propriétés de structuration de matériaux mixtes et fins. Application à l'envasement des systèmes naturels / Study of structuring properties of mixed and fine materials. Multi-scale approach. Application in the mundding of the natural system

Serhal, Saly 19 December 2017 (has links)
Les estuaires sont généralement soumis à des phénomènes de comblement sédimentaires. Dans cette partie des systèmes fluviaux du territoire, l'accumulation des matériaux fins modifie radicalement la morphologie de l'estuaire, et conditionne la présence des espèces animales et végétales et on distingue un impact fort sur le plan économique, social et industriel. Les comblements compliquent la circulation dans les estuaires, compliquent les activités de pêches, de loisirs, modifient les propriétés des écoulements et constituent un facteur risque sur les zones d'habitations voisines. Des solutions temporaires consistent à curer les estuaires et des solutions d'aménagement des estuaires peuvent être envisagées. Néanmoins, il ressort de la littérature un manque important sur la caractérisation des mélanges liquides-solides et sur les mécanismes de structuration. Ce travail s'inscrit dans le contexte de l'étude des mécanismes de structuration des matériaux sédimentaires dans les estuaires afin de mieux comprendre les remplissages des zones estuariennes et surtout d'envisager des solutions durables de « nettoyage » de ces zones. L'estuaire de la Rance est particulièrement ciblé par notre étude. Le but est de donner des éléments de réponse sur le comportement rhéologique des vases naturelles en distinguant les échelles les plus significatives afin de détecter les facteurs structurants qui influencent les paramètres rhéologiques. La rhéologie des sédiments est ainsi étudiée à l'aide du rhéomètre Kinexus, géométrie plan-plan. On a pu alors détecter un comportement visco-plastique Bighamien. L'influence du diamètre moyens et de la fraction volumique solide sur la viscosité et le seuil de la contrainte de cisaillement dynamique du modèle de Bingham sont ainsi analysés. Ensuite, nous avons étudié grâce à des sédiments sans sel et sans matière organique, l'influence de ces deux composés chimiques sur le comportement rhéologiques des sédiments et puis leurs influences sur le vieillissement des sédiments. Une étude statique est également réalisée à l'aide du Va ne test permettant le calcul de la contrainte de cisaillement seuil. •Enfin, une assimilation du piège du Lyvet est réalisée grâce à des colonnes de sédimentation dans des conditions assez proches des conditions naturelles. Un processus de sédimentation-tassement-consolidation sous poids propre est recréé en laboratoire. Les sédiments sont amenés à vieillir cette fois pour des longues durées allant jusqu'à 9 mois. Au terme de périodes de vieillissement retenues, le massif créé est caractérisé depuis l'interface fluide-sédiments. Cela nous a permis d'étudier la répartition granulaire des sédiments après structuration et la variation de la contrainte de cisaillement seuil selon la profondeur de la colonne et la durée du vieillissement. Ce type d'essai est aussi réalisé pour les sédiments sans sel et sans matières organiques. / Estuaries are generally subject of sedimentary filling phenomena that alter their morphology and affect subsequently the economic, social and industrial plans. In this part of the fluvial systems of the territory, the accumulation of fine materials radically modifies the morphology of the estuary, and conditions the presence of animal and plant species and cause a strong impact on the economic, social and industrial. Filling complicates navigation in estuaries, fishing, recreational activities and modifies flow properties and is a risk factor in neighboring housing areas. Temporary solutions consist of cleaning estuaries and estuarine management solutions can be considered. Nevertheless, the literature shows a significant lack of characterization of liquid-solid mixtures and structuring mechanisms. This work is in the context of the study of structuring mechanisms of sedimentary materials in estuaries to better understand the fillings estuarine areas and specially to consider sustainable solutions of "cleansing" of these areas. The Rance estuary is particularly targeted by the study. The aim is to provide answers on the rheological behavior of natural vessels by distinguishing the most significant scales to detect structural factors influencing the rheological parameters. The rheology of the sediments is studied using the Kinexus rheometer, plan-plan geometry. A Bighamien visco-plastic behavior was then detected. The influence of the mean diameter and the solid volume fraction on the viscosity and the threshold of the dynamic shear stress of the Bingham model are thus analyzed. Then, using sediments without salt and organic matter, we studied the influence of these two chemical compounds on the rheological behavior of the sediments and their influence on the aging of the sediments. A static study is also carried out using the Vane test allowing the calculation of the threshold shear stress. Finally, an assimilation of the natural filling phenomenon is achieved in columns under conditions similar to natural conditions. These columns are then filled with natural sediments, washed sediments and sediments free of organic material and left for ages ranging from one week to 9 months. Then, the columns will be disassembled and rheological tests with the Brookfield Rheometer will be performed throughout the depth of the columns as well as measurements of water content and grain size. These tests allow us to study sediment structuring in the long term and also to identify the effect of salt and organic matter on sedimentation.
233

Geomorphic Changes to Florida Bay Within the Past Century

Taylor, Kristian H. 01 November 2009 (has links)
Florida Bay is a shallow, subtropical lagoon located south of the Florida mainland. Bordered by the Florida Keys to the east and south, and shallow mud banks to the west, the Bay is protected from wave action and is considered a low energy environment. Utilizing a 100 year bathymetric dataset the geomorphology of Florida Bay was examined to see if significant changes were occurring despite the lack of strong wave action and water circulation. Changes in bathymetry were investigated from using a high-resolution bathymetric dataset from 1890 and 1990. Analysis was concentrated on the three main ecological habitats of Florida Bay: seagrass beds, mud banks and basins. This study of changes in geomorphology revealed that percent coverage of seagrass beds was positively correlated to amount of shallowing, basins larger than 27 km2 have gotten deeper and the mud banks of Florida Bay have been migrating southward at approximately 1 m/y. The significant changes to bathymetry within Florida Bay reveal that the environment is quite dynamic despite being sheltered from open waters. Most importantly, the presence of the 1890 bathymetric dataset allows for remote sensing techniques to be used to follow geological processes.
234

Adaptation et évaluation d'un système d'anticipation de crues éclair sur des bassins de montagne non-jaugés / Adaptation and evaluation of an early flash floods system on ungauged mountainous basins

Defrance, Dimitri 17 March 2014 (has links)
En Europe, les crues éclair affectent principalement les régions méditerranéennes et montagneuses. Les bassins concernés sont le plus souvent de petite taille. Anticiper ce type d'événements demeure un exercice ardu parsemé de multiples difficultés. Cette thèse s'inscrit dans le cadre d'un projet commun à IRSTEA et Météo-France (projet RHYTMME) et ses deux objectifs sont :l'adaptation de modèle hydrologique de la méthode AIGA aux régions montagneuses, en tenant compte des caractéristiques de cet environnement ;l'évaluation du nouveau modèle sur des bassins de petite taille, qui sont réellement non-jaugés.Pour atteindre le premier objectif, le modèle est complexifié (prise en compte de la neige), testé sur 118 bassins versants jaugés et régionalisé. Quant au second but, des relevés de dégâts, issus de la base de données des services de Restauration des Terrains en Montagne (RTM), sont utilisés afin d'évaluer le modèle sur 123 très petits bassins dans des conditions aussi proches que possible de la réalité du terrain.Pour réaliser ce second objectif, une méthode d'évaluation est développée, fondée sur des statistiques de contingence, illustrant la concomitance entre dégâts observés et dépassement de seuil des débits simulés. Il est proposé un graphe renseignant le taux de détection (POD) et le taux de succès (SR) pour différents seuils simultanément à l'instar des courbes de ROC. Le principal résultat est qu'une évaluation sur bassins jaugés est une première étape nécessaire mais pas suffisante. En effet, les travaux illustrent le fait que les meilleurs modèles sur les bassins jaugés ne le sont pas forcément sur les petits bassins non-jaugés, sujets aux crues éclair. / In Europe, flash floods primarily occur in the Mediterranean and mountainous areas. The concerned basins are often small and ungauged with a short lag time. Anticipating such events is a tricky task with many difficulties. This thesis is part of a common project between Irstea and Météo-France (RHYTMME project) with two objectives : the adaptation of the hydrological model of AIGA method to the mountainous areas, taking into account the environment characteristics the evaluation of the new model on small basins, which are actually ungauged. To achieve the first objective, the model is complicated by the integration of a snow modelling on 118 gauged basins. Then the model is regionalized. The second objective is to use flood reports from the mountain area restoration services database (services de Restauration des Terrains en Montagne (RTM)). The model is evaluated with these reports on 123 very small basins under conditions as close to as possible the reality. To overcome the second objective, an evaluation method is developed, based on contingency statistics, illustrating the coincidence between observed damages and threshold crossing by simulated flows. A graphic with the probability of detection (POD) according to the success rate (SR) is introduced for different thresholds. Thereby, a multi-threshold approach is used to compare hydrological models like ROC-curves. The main result, highlighted by this thesis is an evaluation on gauged basins is a necessary first step but not sufficient. Indeed, the works illustrate that the decided compromises on the large gauged basins don?t lead automatically to the best performances on the small basins occurring flash floods.
235

Vodní zdroje Kyrgyzstánu jako geopolitický nástroj / Water resources of Kyrgyzstan as a geopolitical tool

Dresler, Jan January 2017 (has links)
The thesis deals with the importance of water resources and their influence on political development with the example of Kyrgyzstan. The main objective was to find out the role of water resources in domestic politics, how water influences the relationship between Kyrgyzstan and its neighbors, and whether water resources are of interest to the world's superpowers. Geopolitical analysis was carried out on three levels. At national level, water scarcity, uneven distribution and obsolete water systems are a cause of civil discontent. Corruption in the state sphere negates the possibility of modernization of existing water facilities. Water management is dependent on non-governmental associations and foreign financial assistance. At regional level, there is constant tension between Kyrgyzstan, where all the important rivers of the region rise, and the states lying downstream of these rivers. The cause of this tension is different demands of individual states on water use. International treaties address the situation, but are mostly non-functional in the long term. At the supra-regional level, the interests of especially Russia and China collide. Both superpowers seek to prevent US influence in the region. At the same time, they gain a dominant position in Kyrgyzstan in the economic and security spheres....
236

The nature of the western margin of the Witwatersrand Basin

Van der Merwe, Roelof 07 October 2014 (has links)
D.Phil. (Geology) / The tectonic evolution of the "western margin" of the Witwatersrand Basin is examined and indications are that it has undergone a long and complex history. In order to examine the nature of Witwatersrand-age structures, structures in both pre- and post-Witwatersrand sequences are also examined. Rocks of the ±3074 Ma Dominion Group were subjected to a tectono-metamorphic event prior to the deposition of Witwatersrand strata on an angular unconformity. An oligomictic conglomerate is sporadically developed at the base of the Witwatersrand Supergroup. PreVentersdorp structures in Witwatersrand strata are developed in two distinct trends, north-south and northeast-southwest. The relationship between the two directions of folds and thrust faults are best explained within a regional, sinistral transpressive shear couple; the north-south faults are sinistral strike-slip faults and the northeast-southwest trending folds and thrust faults are secondary structures associated with the strikeslip faults. The implications of this model are that Witwatersrand sedimentation was probably controlled by lateral movements on north-south trending faults and not by thrust faults in a foreland system as suggested by the most recent models of Witwatersrand basin development. Post-Witwatersrand deformation is complex. Southeastward verging, pre-Ventersdorp, thrust faults were reactivated as normal faults during Platberg times and the resultant half-grabens were infilled by conglomerates of the Kameeldoorns Formation. Later deformational events include eastward verging post-Ventersdorp thrust faults and post-Transvaal normal and strike-slip faults. It can be demonstrated that the majority of this later fault movements took place along pre-existing fault planes and therefore tectonic inversion is a fundamental process in the evolution of the Witwatersrand Basin. Clearly therefore, the present distribution of Witwatersrand strata does not reflect the original basin geometry, it is the result of several periods of basin inversion and no basin margins can be defined.
237

Urban stormwater injection via dry wells in Tucson, Arizona, and its effect on ground-water quality

Olson, Kevin Laverne, 1954-, Olson, Kevin Laverne, 1954- January 1987 (has links)
My deepest respect and appreciation are extended to Dr. L. Gray Wilson for providing the opportunity to conduct this research, for his advice and assistance during the course of the research, and for his review of and suggestions for improving this manuscript. I would also like to thank Michael Osborn for his assistance. This research was funded by the City of Tucson. The assistance and direction provided by Mt. Bruce Johnson and Mt. Joe Babcock at Tucson Water are gratefully acknowledged. My thanks are also extended to Dr. Daniel D. Evans, Dr. L.G. Wilson, and Dr. Stanley N. Davis for serving on my thesis committee. Bruce Smith's assistance is gratefully acknowledged. Bruce spent two long days with 110-degree temperatures In a parking lot describing the lithology of sediment samples collected during the drilling phase of this research. He also determined the moisture content and particle size distribution on samples collected from the borehole. The assistance of Ralph Marra and Steve Brooks is also gratefully acknowledged. Ralph waded through city and county bureaucracies to determine zoning at each dry-well site. Steve assisted with collecting dry-well settling chamber sediment samples.
238

Controls on lithofacies variability and organic-matter enrichment in a carbonate-dominated intrashelf basin : a multi-proxy study of the Natih-B Member (Upper Cretaceous Natih Formation, North Oman)

Al Balushi, Said Ali Khamis January 2010 (has links)
Intrashelf basins occurring on epeiric carbonate platforms are commonly associated with the presence of excellent carbonate source rocks, and because they often border potential carbonate reservoirs updip, they may form the core of rich petroleum systems. This is a common phenomenon of many Mesozoic hydrocarbon plays in the Middle East. Despite this fact, studies investigating intrashelf-basinal, fine-grained carbonates are rare, because it is assumed that little lithofacies variability is present in these successions as a consequence of their relatively homogeneous appearance where they are sampled in core or visited in exposures. Those that have been performed mostly lack process-detail analyses, and interpret the organic-carbon enrichment in these sediments to be simply a function of either occurrence of localised bottom-water anoxia or high primary organic production under low-energy conditions, dominated by suspension-settling events.
239

Efeitos das mudanças de uso da terra no regime hidrológico de bacias de grande escala

Bayer, Débora Missio January 2014 (has links)
Os efeitos das alterações de uso da terra na hidrologia das bacias hidrográficas têm sido, ao longo dos anos, amplamente discutidos para pequenas bacias experimentais. O uso de modelos hidrológicos para descrever esse tipo de processo tem se tornado promissor no que tange o estudo de grandes bacias. Sendo assim, o objetivo deste trabalho é avaliar uma metodologia para analisar o impacto das mudanças de uso da terra sobre o regime hidrológico em bacias hidrográficas de grande escala. Este estudo foi realizado por meio de simulação. Para isso foi utilizado um modelo hidrológico distribuído de base física, o Modelo de Grandes Bacias (MGB-IPH). Para realizar simulações de impactos das mudanças de uso da terra, inicialmente avaliou-se a capacidade do modelo MGB-IPH de captar as alterações produzidas pelas mudanças de uso. A análise de sensibilidade mostrou que a vazão gerada na bacia é inversamente proporcional aos parâmetros de índice de área foliar (IAF) e de altura média da vegetação (h), uma vez que quanto maior o IAF, mais interceptação ocorrerá na bacia e, quanto maior o valor de h, mais facilidade haverá nas trocas aerodinâmicas, ambos favorecendo o processo de evaporação. Já em relação aos parâmetros albedo (a) e resistência superficial (rs), a vazão gerada é diretamente proporcional, pois quanto maior o a maior a energia refletida pela superfície e, consequentemente menos energia estará disponível para o processo de evaporação. Em relação à rs, o seu aumento implica em uma menor perda por transpiração, disponibilizando mais água para gerar escoamento. As simulações de análise de sensibilidade mostraram que o MGB-IPH reproduz, de forma coerente, o comportamento médio das bacias submetidas ao desmatamento em um grande número de estudos experimentais. Assim, avaliou-se os impactos das mudanças de uso da terra no regime hidrológico em bacias de grande escala através de um estudo de caso. Este estudo de caso foi realizado na Bacia Hidrográfica do Rio Paraná. Os resultados das simulações mostraram que o desmatamento possui forte influência sobre as variáveis hidrológicas, como interceptação, evapotranspiração e vazão. Devido ao desmatamento foram verificadas reduções na interceptação e na evapotranspiração ao longo dos anos. Em relação a vazão, verificou-se que as simulações foram capaz de captar a não estacionariedade existente nas vazões observadas. Além disso, foi possível verificar que a vegetação pode ser associada a 39% dos incrementos observados na vazão média de longo termo, quando comparados os períodos anterior e posterior a 1970 na Bacia Hidrográfica do Rio Paraná. Já as variações na precipitação são responsáveis por 61% dos impactos na vazão média. Em relação às vazões extremas foram verificados incrementos, sendo eles mais expressivos nas vazões mínimas do que nas vazões máxima. Assim, pode-se afirmar que a metodologia proposta é consistente com os efeitos observados na bacia e com os resultados de estudos experimentais realizados em diferentes regiões do mundo. / The effects of land use change on the hydrology of watersheds have been widely discussed during several years in small basins. The hydrological models have been promising for describe the effects of land use change in hydrology in large basins. Thus, the aim of this study was to evaluate a methodology to study the impact of land use changes on the hydrological processes in large basins. This study was conducted by hydrological simulation. For this, a physically based distributed hydrological model, Modelo de Grandes Bacias (MGB-IPH), was used. The ability of MGB-IPH model for study the effects of land-use change in hydrology processes was first analyzed. The results of sensibility analysis showed that the flow generated in the basin is inversely proportional to the parameters of leaf area index (LAI) and average vegetation height (h), since the higher the LAI more interception, and the higher the h easier will be the aerodynamic changes, both favoring the evaporation process . The flow is directly proportional to the parameters albedo (a) and surface resistance (rs), since the greater the a, more energy reflected by the surface, and consequently less energy is available for the evaporation process. The increasing in rs parameter implies a smaller loss by transpiration, and then more runoff is generated. The sensibility analysis showed that the MGB-IPH reproduces consistently, the average behavior of the basins subjected to deforestation on a large number of experimental studies. Thus, we evaluated the impacts of land use changes on the hydrological regime in large-scale basins by a case study. This case study was conducted in the Paraná River Basin. The simulation results showed that deforestation has a strong influence by hydrological variables, such as interception, evapotranspiration and flow. Due to deforestation were observed interception and evapotranspiration reduction over the years. It was found that the simulations were able to capture the non-stationarity in the observed streamflows. Furthermore, we found that 39% of the observed increase in average flow of long term is due to vegetation change, when comparing the periods before and after 1970 in the Paraná River Basin, while the 61% is due precipitation changes. Increments were observed in extreme flows. These increments were more evident at low flows than the maximum flow. Thus, it can be stated that the proposed methodology is consistent with the effects observed in the Rio Paraná basin and with the results of experimental studies conducted in different regions of the world.
240

Evolução morfométrica do Arroio Chuí no Sistema Laguna-Barreira, Sul da Planície Costeira do Rio Grande do Sul

Oliveira, Rafael Mastracusa de January 2014 (has links)
O conhecimento das estruturas, feições e formas numa bacia de drenagem é parte integrante do reconhecimento de sua evolução e dinâmica. Abordando a avaliação geomorfológica e dinâmica, destacamos todos os fatores físicos ambientais inerentes aos processos de formação das estruturas e feições. O presente trabalho tem como objetivo principal propor uma caracterização morfométrica da microbacia do arroio Chuí a partir da identificação do divisor de águas adjacente ao arroio Pastoreio, na região sul do estado do Rio Grande do Sul. A identificação da nascente do arroio, foi realizada preliminarmente pela análise em imagens do satélite Landsat 5 sensor TM do ano 2009 associado a dados do modelo digital de elevação (SRTM), sendo posteriormente identificado por observações em campo. Em campo, foi realizado levantamento topográfico na região do divisor de águas com a finalidade de melhor caracterização das suaves variações morfológicas da área. Em laboratório, foram processados e refinados os dados coletados em campo para modelagem tridimensional da área do divisor de águas dos arroios Chuí e Pastoreio. Em ambiente de SIG (Sistemas de Informações Geográficas) foram realizadas interpolações de cotas altimétricas dos pontos coletados em campo utilizando-se os métodos da krigagem e TIN (triangulated irregular network). Através da análise dos modelos tridimensionais gerados, foi identificado o ponto divisor de águas dos arroios, sendo determinante para a posterior delimitação da microbacia do arroio Chuí. A partir da identificação do divisor de águas e conhecimento da nascente do arroio Chuí, foi possível a definição do limite superior da microbacia, e assim caracterizar com maior precisão suas formas e dimensões. Com o uso dos dados do SRTM corrigidos, para a região sul do estado, foram geradas curvas de nível com precisão de 5m, interpolando suas cotas mais elevadas com a ferramenta Watershed (ArcGIS 10®) e definindo-se a área da microbacia do arroio Chuí com 58.796,72ha. Tais métodos de trabalho mostraram-se eficazes na caracterização morfométrica da área de estudo e proporcionaram subsídios ao mais preciso dimensionamento da microbacia do arroio Chuí, acarretando no melhor manejo dos recursos naturais dispostos. / The knowledge of the structures, features and forms a drainage basin is part of the recognition of his evolution and dynamics. Addressing the geomorphological and dynamic evaluation, we highlight all physical environmental factors inherent to the formation of structures and features. This paper has the main objective to propose a morphometric characterization of the Arroio Chuí basin from the identification of the watershed adjacent to Arroio Pastoreio, the southern state of Rio Grande do Sul. Identifying the source of the Arroyo Chuy, was preliminarily performed by analysis on satellite image Landsat 5 sensor TM of 2009 associated with the digital elevation model (SRTM and later identified by survey in field. In the field, topographic survey was conducted in the watershed region in order to better characterize the soft morphological variations of the area. In the laboratory, were processed and refined data collected in the field for three-dimensional modeling of the watershed of the Arroio Chui and Arroio Pastoreio. In the GIS (Geographic Information Systems) interpolations of elevations points collected in the field using the methods of kriging and TIN (triangulated irregular network) were performed. Through the analysis of three-dimensional models generated, the dividing point of the rivers of waters, being decisive for the further delineation of the Arroio Chuí basin was identified. From the identification of the watershed and the source of knowledge Arroyo Chuy, we define the upper limit of the basin, and so more accurately characterize their shapes and dimensions. With using a digital elevation model SRTM adjusted of the southern state, level curves were generated with an accuracy of 5m, interpolating their highest values with the Watershed tool (ArcGIS®10) and defining the area of the Arroio Chuí basin to 58796.72ha. Such working methods were effective in morphometric characterization of the area and provided subsidies to more accurate sizing of the Arroyo Chuy basin, resulting in better management of natural resources arranged.

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