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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.
141

Avaliação isotópica e hidoquímica na porção noroeste Cauê, Quadrilátero Ferrífero, Brasil

Jussara Brant de Carvalho 24 August 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A APA Sul RMBH, Área de Proteção Ambiental Sul da Região Metropolitana de Belo Horizonte, localizada na porção noroeste de uma das maiores regiões produtoras de minérios, o Quadrilátero Ferrífero, é conhecida pela riqueza de sua biodiversidade, seus aspectos sócioculturais e econômicos e, principalmente, pelo seu grande potencial mineral. Nela ocorre a Formação Cauê, formação geológica conhecida pela ocorrência de minérios ferrosos e também por abrigar grandes volumes de água no subsolo. Essa unidade hidrogeológica, conhecida como Aquífero Cauê, é o objeto de estudo desse trabalho. A área delimitada para este estudo encontra-se quase completamente inserida da APA Sul e está localizada na porção noroeste do Quadrilátero. Foram realizadas medidas em quarenta e sete amostras água, entre nascentes, cabeceiras de drenagem, drenos e poços. Foram amostrados pontos de surgência dos Aquíferos Inconsolidados, Gandarela, Quartizítico, Unidades Confinantes, mas principalmente o Aquífero Cauê, no período de estiagem das chuvas em 2011. Estas amostras tiveram seu conteúdo de deutério, oxigênio-18 e trítio determinados. Destas, vinte e três também tiveram suas características químicas investigadas. Águas de chuva foram coletadas durante um ano em três pontos na área de estudos. O conteúdo de trítio e razões isotópicas de deutério e oxigênio-18 foram determinados para amostras mensais de precipitação. Os resultados possibilitaram a determinação da Linha Meteórica Local, além da atividade atual de trítio nas precipitações que subsidiou o cálculo de tempo de renovação das amostras água subterrânea. A Linha Meteórica obtida evidenciou desvio da Linha Meteórica Global quanto ao excesso de deutério. Os Efeitos Quantidade e Temperatura puderam ser observados na região. A baixa mineralização das águas do Cauê, evidenciada pelos baixos valores de condutividade elétrica, dificultou a classificação das águas, e um padrão químico não pode ser observado. Os resultados de 18O e 2H indicaram rápida infiltração para a maioria das amostras, com exceção de um grupo cuja maioria é composta por águas relacionadas aos aquíferos de cobertura. O tempo de renovação das águas subterrâneas foi calculado pelos Modelos de Fluxo em Pistão e Exponencial. Os resultados apresentaram grande variação, entre 1,5 e 279 anos. / The Environmental Protection Area of the South Metropolitan Region of Belo Horizonte City, known as APA Sul RMBH, located on the northwestern portion of one of the largest oreproducing regions, named Quadrilátero Ferrífero (Iron Quadrangle), is known for the richness of its biodiversity, its socio-cultural and economic and especially to its great mineral potential. In this area, occurs the Cauê Formation, a geological formation recognized for the high occurrence of iron ores and also host large volumes of fresh water in the underground. This hydrogeologic unit, known as Cauê Aquifer, is the object of study of this work. The area defined for this study is almost completely inserted into the cited protection are and is located in the northwestern portion of the Quadrangle. Measurements were taken in forty-seven water samples, including springs, headwater drainage, drains and wells. Sampled were taken of unconsolidated aquifers, Gandarela, Quartizitic, confining units, but mainly Cauê Aquifer, during the dry season rainfall in 2011. These samples had the content of deuterium, oxygen- 18 and tritium determined. Of those, twenty-three were also investigated about its chemical characteristics. Rainwater was collected during one year at three stations located the study area. The content of tritium and deuterium isotope ratios and oxygen-18 were determined on monthly samples of precipitation. The results allowed the determination of the Local Meteoric Water Line, beyond the current activity of tritium in precipitation that supported the calculation of groundwaters residence time. The Local Meteoric Line obtained showed considerable deviation from the Global Meteoric Line on the excess of deuterium, while the slope was similar to the global one. The quantity and temperature effects were observed. The low mineralization of the groundwaters, evidenced by low values of electrical conductivity has obstructed their classification. A chemical pattern could not be attributed to the aquifer. The 18O and 2H results indicate rapid infiltration for most samples, except for a group formed mainly by water related to unconsolidated aquifers. The residence time of groundwater samples was calculated by piston flow and exponential flow models. The results showed a great variation, with waters between 1.5 and 279 years old.
142

Contaminação de solos por metais tóxicos provenientes do descarte inadequado de pilhas Zinco-Carbono de uso doméstico / Soil contamination of toxic metals from zinc carbon batteries inadequate disposal

Vanessa Santos Oliveira Gazano 29 March 2006 (has links)
O presente trabalho determinou a concentração dos metais zinco, manganês, cádmio, chumbo, níquel, cobre e cromo no efluente e solo de quatro colunas de latossolo indeformadas. Duas colunas foram contaminadas por pilhas do tipo zinco-carbono e duas colunas foram utilizadas como referência, além de pilhas isoladas, foram todas lixiviadas por uma solução \"água de chuva\" (HNO3 + H2SO4, pH 4,0). Os metais no efluente e no solo foram determinados pela técnica de ICP-OES. A avaliação do efluente e do solo das colunas contaminadas pelas pilhas mostrou um incremento das concentrações dos metais, principalmente de zinco, manganês e chumbo. A sequência das massas acumuladas dos metais no efluente e no solo da coluna contaminada apresentaram uma sequência semelhante a da lixiviação isolada da pilha (Zn > Mn > Pb > Cr > Cu > Ni > Cd), confirmando a influência da pilha nas concentrações dos metais no efluente e solo das colunas. Observou-se também que a contaminação de Zn e Mn tende a migrar da camada superior da coluna de solo para as camadas inferiores. O estudo mostrou que as pilhas podem causar uma contaminação significativa do solo para os metais Zn, Mn e Pb e possivelmente também para Cd. Esta contaminação do solo poderia vir a causar uma contaminação da água subterrânea para os metais Zn, Mn e Pb, dependo das características do perfil do solo. / The aim of the present study was to determine the concentration of Zn, Mn, Pb, Cd, Cu, Cr, and Ni in an oxisol column contaminated with zinc-carbon batteries. Two control and two contaminated columns, and batteries alone were leached for a periods of six months and one year with aqueous solution of HNO3 and H2SO4 (1:1, pH 4,0) to simulate rainwater. The metal concentrations in effluent and soil were measured by means of ICP-OES technique. Results from the contaminated column showed enhanced concentrations in both effluent and soil (mainly zinc, manganese and lead). In addition, the total amount of metals in effluent and soil showed similar sequence order as observed for batteries alone (Zn > Mn > Pb > Cr > Cu > Ni > Cd) indicating that batteries can be considered the main source of contamination. We also observed migration of Zn and Mn from the top to the lower layers of the soil columns. The study gives further evidence that batteries can significantly contaminate the soil with metals like Zn, Mn and Pb, and maybe Cd too. This soil contamination combined with the enhanced concentrations found in the effluent can point out a probable groundwater contamination.
143

Modelling Of Single And Multiple Recharge Wells In Layered Aquifers

Majumdar, Pradeep Kumar 08 1900 (has links)
Artificial recharge and rainwater harvesting methods are being applied for mitigating effects of groundwater depletions in severe over-drafting urban and rural situations. When the aquifer to be recharged is situated at some depth below the ground surface and topped by a semi-previous layer with a large resistance against vertical water movement, recharge wells are the most appropriate solution. Water is injected by free or forced recharge technique by maintaining constant or variable head or rate of injection in the recharge well. A review of literature, carried out in two parts, looks into the aspects and performance of the practical field applications of recharge wells all over the world in Chapter II, whereas available theoretical solutions are reviewed in chapter III. The review indicates that free recharge conditions are analysed using slug theories and mirror image type curve analysis is helpful in dealing with forced recharge cases. Many slug test and pumping test theories developed focus either on simplistic recharge conditions or homogeneous hydro-geological conditions. Also, separate developments exist in the areas of large diameter well and flow to multi-aquifer system. These developments are mainly concentrated on constant wellhead boundary conditions with no well loss. Many researchers have dealt effect of pumping on base flow numerically, but the study on the impacts of recharge on base flow has not been noticed. One more practical issue, which has not been studied, is the aquifer clogging during well injection, though related background research on filtration phenomena is comparatively well established. Analytical solution for recharge in a finite aquifer from a large diameter well under variable head is obtained in Chapter IV. Furthermore, issues of analytical solution difficulty, in the available solution with constant head boundary condition are resolved and extended using Discrete Kernel approach to variable heads. Usefulness of choosing the variable head boundary condition lies in the advantage that continuous pouring of water in to the recharge well is not a necessary condition. As well and aquifer clogging is minimum in hard rock terrains, present solution is useful for estimating the pressure heads and recharge rates in the well flooding techniques frequently used in hard rock regions. For the case of free recharge in confined aquifers, available slug test theories do not consider appropriate well storage and well loss, as these may not be significant in the case of short duration test with instantaneous slug. Also slug theories are not extendable to multi-aquifer wells. Analytical solutions are obtained for free recharge condition for both single and multiple layer aquifers in chapter V, also incorporating well loss, well storage and friction loss. Parametric studies are made to see the effect of hydro-geological parameter namely; transmissivity and storativity, on recharge rates and head buildups. Theis (1935) solution is provided with well storage effects for the entire period of recharge, using Duhamel’s convolution theorem. Comparison with Cooper et al. (1967) shows, that the present solution could be useful for long-term non-instantaneous free recharge data analysis. Relationship between diffusivity and time to decay has been developed, which is useful for aquifer parameter estimation using recharge test data. Similar improvement is feasible for other existing type curves also including leaky aquifers. Analytical solutions for free recharge with constant well loss, variable well loss and losses due to friction have been developed. Comparison indicates better solution with losses due friction, which is also a more easily measurable physical parameter as compared to other well loss constants. Free recharge solutions provide unique opportunity to estimate the recharge rates in the individual aquifers of single and multi-layered aquifer. Well bore interaction has been accounted through recharge well injecting water to multi-aquifers. Specific analytical solutions are developed for the cases of free recharge in hard rock multi-layered aquifers. Present state of the art for recharge well considers forced recharge as mirror image of the pumping test solutions, type curves of which are found more difficult to fit in to the recharge test data. Again, deviation in type curve match lies in considering well storage, well clogging and aquifer clogging effects. In chapter VI analytical forced recharge solutions are developed for constant and variable rate of injection. Mirror image Theis (1935) solution is coupled with well storage during the recharge period to improve the existing solution and make it suitable for recharge computation after comparing it with Popodopulos and Cooper (1967) solution. Well bore interaction in case of multi-layered aquifer has been considered. Similar exercises are possible with existing solutions other than Theis (1935) including those for leaky aquifers. Type curves for recharge for various diffusivity ratios have been developed. Constant and variable well loss is considered for forced recharge in single as well as multi-layered aquifer. Results say that present solutions are more accurate in terms of well storage, which has significant influence on well injection as compared to well pumping. In the case of pumping, well storage effects are dominant in the initial times, where as it effects the entire recharge cycle, also depend upon the aquifer diffusivity and the recharge column dimensions. Significant influence of well loss in case of forced well recharge has been taken care of by considering linear trend of deteriorating well condition between times dependant Walton’s well loss constant. In Chapter VII, aquifer clogging, changing with time has been analysed using numerical modelling technique and applying the results of the filtration experiments reported in the literature. Inclined initial piezometric water table condition is found effective towards observation well water level and is considered for simulation of the observation well water level of Hansol project. The methodology is transferable for analyzing other injection project also. Base flow on regional scale is affected by the location, rate of injection and number of wells. In the case of Bamnod injection well project, base flow retained in the aquifer, is reducing with the increase in the quantity of injected water. This conclusion may not always be same everywhere, however, this aspect needs to be investigated. Chapter VIII summaries and highlights the conclusions drawn out of the present research study. It has been summarized that the Chapters IV, V and VI develop analytical solutions for recharge rates under unsteady wellhead condition by coupling existing groundwater flow solution with Duhamel’s convolution theorem. It provides the well storage effects throughout the recharge cycle, which unlike in pumping cases, could be significant in recharge cases. Second foremost specific requirement for a well recharge may be the consideration of head loss. In free recharge cases friction factor per unit diameter of recharge well is found a better physically computable parameter, where as well loss constants suggested by Walton (1962) could bring the head loss effects in the developed solutions for forced recharge. Free and forced recharge solutions developed for single aquifer are further extended to multi-aquifer system with respective head loss effects and well bore interaction. This is an useful contribution owing to the fact that no multi-aquifer solution considers aquifer interactions through recharge well and equivalent single aquifer theory worked for the multi-aquifer system without head loss All the solutions in Chapters IV, V and VI are found sensitive towards well radius and could analyze recharge behavior at the well face with horizontal initial piezometric surface. Simulation of the response in an observation well situated 50 m away from the recharge well is found inappropriate with the present solution. Therefore in the Chapter VII, to solve the solution difficulty, analysis is extended for the observation well, some distant away from the recharge well face, using numerical solution technique. Heterogeneity in the flow medium between the recharge well and the observation well is considered as per the time dependant aquifer clogging, based upon theory of filtration. Recharge well in general has been considered as a technology, which would increase the groundwater storage. With a case study it is found that groundwater regime also plays a crucial role in this respect. Present thesis also provides specific solution to practical issues like; estimation of diffusivity from time to decay of recharge, friction loss in the recharge well, time variant well loss as per recharge well condition, effect of sudden pump shut down, control of injection rates against recharge well over flooding, recharge rates to individual aquifers of a multi-aquifer system and multiple well recharge options. Though the scope of the present research is confined to aquifer-aquiclude system only, it could easily be extended to various other hydro-geological setups also. Unique feature of the applied analytical solution technique lies in the flexibility of transformation between head and flux boundary conditions. This provides an opportunity to compute recharge rates and corresponding heads simultaneously with any kind of boundary conditions.
144

Approche topographique historique du sous-sol parisien 1800-2000 : la ville épaisse : genèse et évolutions morphologiques. / A topographic and historical approach of the Parisian underground Urban thickness : creation and morphological evolutions

Fernandez, Mathieu 12 December 2014 (has links)
Le sous-sol de Paris est reconnu et topographié depuis environ deux siècles par plusieurs disciplines. Dans cette thèse, nous avons retenu et analysé depuis leur genèses, souvent intimement liées sur le territoire urbain, ces disciplines de l’épaisseur : la géologie, l’hydrogéologie, l’archéologie, la topographie, puis ce que nous nommons actuellement le génie urbain. L’urbanisme, accepté comme « science de l’organisation spatiale des villes », possède peu de méthodes d’appréhension à même de synthétiser dans le temps et l'espace la diversité de ces approches. La méthode proposée par la thèse rend représentables et quantifiables plusieurs évolutions longues issues des « mesures de ville » étalées dans le temps, à travers un Système d’Information Géographique construit dans une perspective diachronique. Il concerne ici spécifiquement la verticalité. Plusieurs cartographies originales concernant le mouvement du sol et de la nappe phréatique en sont issues.Sur la base de ce support, intégrant la topographie historique, environnementale et tridimensionnelle de plusieurs disciplines urbaines, nous développons deux pistes d’analyse.La première est la compréhension de la construction du projet urbain au XIXe siècle jusqu’aux « grands travaux » à la lumière de la mesure de l’espace et des représentations disponibles. Une chronologie spécifique est proposée.La seconde est une proposition pour un récolement urbaniste souterrain appréhendant le temps long et l'épaisseur de la ville. Elle peut contribuer aux bases de données urbaines, actuellement en majorité construites sur un espace conçu comme parcellaire.Le modèle vise donc à fournir une contribution et de nouvelles pistes de recherches à la fois pour la morphologie préindustrielle de Paris, pour l’archéologie industrielle et plus généralement pour l'approche urbaniste de la couche, désormais connue dans un cadre géologique et environnemental, mais encore non définie du point de vue stratigraphique, sous le nom d'anthropocène. / For more than two centuries now, researchers from different backgrounds and disciplines have started studying and making topographical surveys of the Parisian underground.These different ways of studying urban thickness all inform this thesis. They are all analyzed from their very origins, which are often closely linked in an urban context. These methods include: geology, hydrology, archeology, topography, and what is currently called urban engineering. Urbanism, although it is often described as “the science of spatial organization in cities”, can seldom yield as much temporal and spatial information as these various approaches can when put together. This thesis proposes to present and quantify several long-term evolutions, traced through a series of “urban measurements” performed over time by a Geographical Information System, which was designed for the purposes of a diachronic study. The system here specifically targets urban verticality. It has resulted in the creation of many original maps of ground and ground-water movement.Based on these maps, which include historical, environmental and tridimensional topography, two analyses are then conducted.The first deals with understanding the construction of an urban project in the 19th century - up until the “grands travaux” - by looking at space measurement and available representations. A specific chronology is then proposed.The second analysis offers to compile information concerning the thickness of the urban underground and its evolution through time. This could then dispense information to urban databases, many of which are currently based on an urban space fragmented by plots.The model thus built serves to contribute and to give new research perspectives, to the study of Parisian preindustrial morphology, and industrial archeology, and more generally the urban approach of the layer - known in geological and environmental contexts, but which has yet to be defined from a statigraphic point of view - under the name anthropocene.
145

Perceptions of rural water service delivery : the case of Ugu District Municipality / Timothy Bheka Cele

Cele, Timothy Bheka January 2012 (has links)
The start of the 21th century is notable for the apparent lack of safe drinking water and sanitation. Over one billion people in all parts of the world lack access to clean water. Most live in developing countries, such as Africa. Unsafe water and poor sanitation have been primary causal factors in the vast majority of water-borne diseases, especially diarrheal ones. The South African Constitution (Act 108 of 1996, Chapter 2, Section 24) states: “Everyone has the right: (a) To an environment that is not harmful to their health and their wellbeing; and (b) To have the environment protected, for the benefit of present and future generations, through reasonable legislative and other measures that prevent pollution and ecological degradation; promote conservation; ecologically sustainable development, and the use of natural resources, while promoting justifiable economic and social development.” Secondly, section 27 states that: “Everyone has the right to have access to: (a) Health-care services, including reproductive health care; (b) Sufficient food and water; and (c) Social security, including, if they are unable to support themselves and their dependants, appropriate social assistance.” These factors have prompted this research within the Ugu District Municipality on the perceptions of inadequate rural water service delivery. This study reveals information on those areas in the Ugu District Municipality, which do not have access to clean water, and on the health hazards that might lead to death if residents’ lack of access to clean water persists. The Ugu District Municipality, is situated in KwaZulu-Natal Province, and covers a surface area of 5866 km2. There are six local municipalities in this district. These are: Ezinqoleni, Umzumbe, Umziwabantu, Hibiscus Coast, Umdoni and Vulamehlo. The node is 77% rural and 23% urban, and the total population for this area is 704027 (Ugu District Municipality IDP 2nd 2011/2012:19). / M. Development and Management (Water Studies), North-West University, Potchefstroom Campus, 2012
146

Perceptions of rural water service delivery : the case of Ugu District Municipality / Timothy Bheka Cele

Cele, Timothy Bheka January 2012 (has links)
The start of the 21th century is notable for the apparent lack of safe drinking water and sanitation. Over one billion people in all parts of the world lack access to clean water. Most live in developing countries, such as Africa. Unsafe water and poor sanitation have been primary causal factors in the vast majority of water-borne diseases, especially diarrheal ones. The South African Constitution (Act 108 of 1996, Chapter 2, Section 24) states: “Everyone has the right: (a) To an environment that is not harmful to their health and their wellbeing; and (b) To have the environment protected, for the benefit of present and future generations, through reasonable legislative and other measures that prevent pollution and ecological degradation; promote conservation; ecologically sustainable development, and the use of natural resources, while promoting justifiable economic and social development.” Secondly, section 27 states that: “Everyone has the right to have access to: (a) Health-care services, including reproductive health care; (b) Sufficient food and water; and (c) Social security, including, if they are unable to support themselves and their dependants, appropriate social assistance.” These factors have prompted this research within the Ugu District Municipality on the perceptions of inadequate rural water service delivery. This study reveals information on those areas in the Ugu District Municipality, which do not have access to clean water, and on the health hazards that might lead to death if residents’ lack of access to clean water persists. The Ugu District Municipality, is situated in KwaZulu-Natal Province, and covers a surface area of 5866 km2. There are six local municipalities in this district. These are: Ezinqoleni, Umzumbe, Umziwabantu, Hibiscus Coast, Umdoni and Vulamehlo. The node is 77% rural and 23% urban, and the total population for this area is 704027 (Ugu District Municipality IDP 2nd 2011/2012:19). / M. Development and Management (Water Studies), North-West University, Potchefstroom Campus, 2012
147

Numerical analysis using simulations for a geothermal heat pump system. : Case study: modelling an energy efficient house

Ilisei, Gheorghe January 2018 (has links)
The ground source resources are becoming more and more popular and now the ground source heat pumps are frequently used for heating and cooling different types of buildings. This thesis aims at giving a contribution in the development of the thermal modelling of borehole heat storage systems. Furthermore, its objective is to investigate the possibility of implementing of a GSHP (ground source heat pump) with vertical boreholes, in order to deliver the heating and cooling demand for a passive house and to emphasize some certain advantages of this equipment even in the case of a small building (e.g. residential house). A case study is presented to a suitable modelling tool for the estimation of the thermal behaviour of these systems GSHP by combining the outcome from different modelling programs. In order to do that, a very efficient residential solar house (EFden House – a passive residential single-family house, which was projected and built in Bucharest with academic purposes) is being analysed. The numerical results are produced using the software DesignBuilder, EED (Earth Energy Designer) and a sizing method for the length of the boreholes (ASHRAE method). The idea of using 2 different modelling programs and another sizing method for the borehole heat exchanger design (ASHRAE method) is to make sure that all the calculations and results are valid and reliable when analysing such a system theoretically (in the first phases of implementing a project), before performing a geotechnical study or a thermal response test in order to assess the feasibility of such a project beforehand. The results highlight that the length of the borehole, which is the main design parameter and also a good index in estimating the cost of the system, is directly influenced by the other fundamental variables like thermal conductivity of the grout, of the soil and the heat carrier fluid. Also, some correlations between these parameters and the COP (coefficient of performance) of the system were made. The idea of sizing the length of boreholes using two different methods shows the reliability of the modelling tool. The results showed a difference of only 2.5%.  Moreover, the length of borehole is very important as it was calculated that can trigger a difference in electricity consumption of the GSHP up to 28%. It also showed the fact that the design of the whole system can be done beforehand just using modelling tools, without performing tests in-situ. The method aims at being considered as an efficient tool to estimate the length of the borehole of a GSHP system using several modelling tools. / <p>The presentation was made via Skype due to the programme being online based</p>
148

Reavalia??o de crit?rios estruturais na hidrogeologia de terrenos cristalinos, com ?nfase na neotect?nica e sensoriamento remoto

Coriolano, Ana Catarina Fernandes 13 September 2002 (has links)
Made available in DSpace on 2015-02-24T19:48:40Z (GMT). No. of bitstreams: 1 AnaCF_ate cap6.pdf: 4452178 bytes, checksum: 27b2ccb7e47f9a71ccabd7ab319267a6 (MD5) Previous issue date: 2002-09-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Hydrogeological prospecting in Northeast Brazil and in other crystalline terrains has been developed on the basis of structural and regional geology concepts that date back to the 50-60 decades and, as such, demand a natural re-evaluation and update. In this kind of terrain, the percolation and accumulation of ground water are controlled by fractures and other types of discontinuities, such as foliations and geological contacts that, through weathering, impart porosity and permeability to the rocks, allowing water flow and storage. Several factors should be considered in the process of locating water wells, as discussed in the literature. Among these, the kind of structures, fracture geometry (including aperture and connectivity) and their geological and chronological context. It is important to correlate fracture systems with the regional neotectonic framework. Fractures at low angle (sub parallel) with the principal stress axis (s1) are those which tend to open (actually they work as tension joints) and, in principle, would present major hydric potential; in the opposite side, fractures at high angle to s1 would behave as closed by a compressional component. Fractures diagonal to the compression and tension axes correspond to shear fractures and, due to their connectivity with second fractures, are also important in terms of hydric potential. Uplift followed by terrain denudation leads to decompression and a general tendency to open (aided by weathering processes) fractures and other rock discontinuities, at different orientations. Low angle fractures, formed in this context, are equally important to increase connectivity, collection of water and recharge of the aquifer systems. In a general way, an opening component (neotectonic or by terrain decompression) and several models to increase fracture connectivity correlate with a greater hydric potential of these structures. Together with parallel research, this thesis addresses models of ground water occurrence in crystalline terrains, either improving well established concepts like the (Riacho-Fenda model), but also stressing other possibilities, like the role of alluvium and paleo-regoliths (the Calha El?vio-Aluvionar model) and of strongly altered, permo-porous zones placed at variable depths below the present surface, flanking several types of discontinuities, especially interconnected fracture arrays (the Bols?es de Intemperismo model). Different methodological approaches are also discussed in order to improve success rates in the location of water wells in crystalline terrains. In this methodological review, a number of case studies were selected in the eastern domain of the State of Rio Grande do Norte, involving the localities of Santa Cruz, Santo Ant?nio, Serrinha, Nova Cruz, Montanhas, Lagoa de Pedras and Lagoa Salgada. Besides the neotectonic analysis of brittle structures, this Thesis addresses the validation of remote sensing as a tool for ground water prospecting. Several techniques were tested in order to detect and select areas with higher potential for ground water accumulation, using Landsat 5-TM and RADARSAT images, besides conventional aerial photos. A number of filters were tested to emphasize lineaments in the images, improving their discrimination, to identify areas with higher overburden humidity, which could reflect subsurface water accumulation, as well as alluvium and other sedimentary covers that might act as recharge zones. The work started with a regional analysis with the orbital images, followed by analysis of aerial photos, up to a detailed structural study of rock exposures in the terrain. This last step involved the analysis of outcrops surrounding wells (in a ray of approximately 10 to 100 m) with distinct productivities, including dry examples. At the level required for detail, it was not possible to accomplish a statistical approach using the available well data catalogs, which lack the desired specific information. The methodology worked out in this Thesis must undergo a testing phase through location of new water wells. An increase in the success rates as desired will led to a further consolidation step with wider divulgation of the methodology to private companies and governmental agencies involved in ground water prospecting in crystalline terrains / A prospec??o hidrogeol?gica no Nordeste do Brasil e em outros terrenos cristalinos tem sido baseada em conhecimentos de Geologia Estrutural e Regional que, pelo tempo decorrido, demandam uma natural reavalia??o. Neste tipo de terreno, a percola??o e ac?mulo de ?gua subterr?nea s?o controlados por fraturas e outros tipos de descontinuidades, tais como folia??es e contatos geol?gicos, que intemperizados adquirem certa porosidade e permeabilidade, permitindo o fluxo e/ou reten??o de ?gua. Diversos fatores devem ser considerados no processo de loca??o de um po?o para ?gua, conforme amplamente discutido na literatura. Dentre estes, o tipo de estrutura observada, a geometria do fraturamento (incluindo abertura e conectividade) e seu contexto geol?gico e cronol?gico. Neste ?ltimo sentido, ? importante correlacionar o fraturamento com o arcabou?o neotect?nico conhecido na regi?o. Fraturas orientadas em baixo ?ngulo (subparalelas) com o eixo de tens?o principal (s1) s?o aquelas que tendem a abrir (funcionam atualmente como juntas de distens?o) e apresentam, em princ?pio, maior potencial h?drico; em situa??o oposta situam-se as fraturas em forte ?ngulo com s1 (corresponderiam a fraturas fechadas , com um componente de compress?o). As fraturas diagonais ?s dire??es de compress?o e distens?o s?o equivalentes ?s fraturas de cisalhamento e, pela conectividade com planos de segunda ordem, s?o tamb?m importantes em termos de produtividade h?drica. A denuda??o do terreno tamb?m enseja descompress?o e uma tend?ncia geral de abertura (inclusive pelo efeito do intemperismo) de fraturas e outras descontinuidades, em orienta??es quaisquer. Fraturas de baixo ?ngulo, formadas nesse contexto, s?o igualmente importantes para definir a conectividade, coleta de ?gua e a recarga dos sistemas aq??feros. De um modo geral, um componente de abertura (neotect?nico ou pela descompress?o) e os v?rios modelos de interconex?o de fraturas resultam no aumento de sua potencialidade h?drica. Em conjunto com pesquisas em paralelo, a presente Tese aborda modelos de ocorr?ncia de ?gua subterr?nea no cristalino, procurando aperfei?oar conceitos j? estabelecidos (como o modelo Riacho-Fenda) e enfatizando outras possibilidades, a exemplo do papel de aluvi?es e paleo-regolitos (o modelo Calha El?vio-Aluvionar) e de zonas fortemente alteradas (permo-porosas) em subsuperf?cie, ladeando v?rios tipos de descontinuidades, em especial fraturas interconectadas (o modelo Bols?es de Intemperismo). S?o tamb?m discutidos diferentes aspectos metodol?gicos atualmente utilizados na loca??o de po?os, fazendo uma reavalia??o destes procedimentos com vistas a aumentar o ?ndice de acerto nas loca??es de po?os em terrenos cristalinos. Nessa metodologia, foram estudadas ?reas selecionadas, no interior do Rio Grande do Norte, envolvendo os munic?pios de Santa Cruz, Santo Ant?nio, Serrinha, Nova Cruz, Montanhas, Lagoa de Pedras e Lagoa Salgada, todos na regi?o oriental do Estado. Al?m de fazer uma an?lise neotect?nica do fraturamento, esta Tese aborda a validade da utiliza??o de sensoriamento remoto como ferramenta na prospec??o de ?gua subterr?nea. Foram testadas v?rias t?cnicas que pudessem facilitar a detec??o e sele??o de ?reas com maior potencial para o ac?mulo de ?gua subterr?nea, utilizando imagens Landsat 5-TM, RADARSAT e fotografias a?reas. Assim, foram utilizados filtros que melhor real?assem os lineamentos observados nas imagens, facilitando a sua discrimina??o, e destacassem ?reas com maior umidade no terreno, que pudessem refletir o ac?mulo de ?gua em subsuperf?cie, bem como coberturas sedimentares e aluvi?es que servem como zonas de recarga. O trabalho partiu de uma an?lise regional com as imagens orbitais, passando pela an?lise de fotografias a?reas, at? um estudo de detalhe, com estudo estrutural de afloramentos em campo. Esta ?ltima envolveu a an?lise de afloramentos pr?ximos a po?os pr?-existentes (em um raio de aproximadamente 10 a 100m), com produtividade distinta, inclusive secos. Ao n?vel de detalhamento requerido, n?o foi poss?vel realizar um trabalho estat?stico utilizando os dados (fichas) de po?os, pela falta das informa??es espec?ficas requeridas. Todo este acervo de conhecimentos gerados deve agora passar por uma fase de testes atrav?s de loca??es espec?ficas. O aumento no ?ndice de acertos, assim pretendido, pode ent?o conduzir a uma etapa posterior de consolida??o e divulga??o da metodologia, para empresas e ?rg?os envolvidos na prospec??o de ?gua subterr?nea em terrenos cristalinos
149

Mercúrio na área de disposição final dos resíduos sólidos do munícipio de São Pedro da Aldeia – RJ

Spinola, Eduardo Costa 24 October 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-10-24T14:24:59Z No. of bitstreams: 1 Mercúrio na área de disposição final dos resíduos sólidos do Município de São Pedro da Aldeia - R.pdf: 1346116 bytes, checksum: bcb9b68a2545bcaaa2fb66437b33505e (MD5) / Made available in DSpace on 2017-10-24T14:24:59Z (GMT). No. of bitstreams: 1 Mercúrio na área de disposição final dos resíduos sólidos do Município de São Pedro da Aldeia - R.pdf: 1346116 bytes, checksum: bcb9b68a2545bcaaa2fb66437b33505e (MD5) / Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / A água é fator de produção e elemento fundamental para o desenvolvimento dos povos. Com a intensificação do seu uso, a água é encarada como um recurso finito. Isto é causado pelo crescimento da população. Como conseqüência da crescente oferta do lixo gerado por bens de consumo descartáveis e resíduos sólidos industriais diversos. São improvisadas áreas de destino aos resíduos sólidos sem uma infra-estrutura adequada. Essas áreas, freqüentemente acabam se tornando definitivas e gerando uma série de transtornos. Essas áreas, os “lixões”, são fontes do elemento mercúrio (Hg) que é considerado um poluente global com boa mobilidade, encontrado principalmente na água e alimentos aquáticos, capaz de causar disfunções no sistema nervoso deixando a população mundial em constante alerta. Esta poluição restringe o uso da água, devido a problemas ambientais e danos à saúde da população. No município de São Pedro da Aldeia, foram realizadas análises químicas, em água e sedimento em área de “lixão”, medindo a concentração de Hg e alguns outros metais (Fe, Mn e Zn), matéria orgânica, pH, condutividade e sulfeto, com o propósito de quantificar a concentração dos metais e estudar seu comportamento na região. / The water is a factor of production and fundamental element for the development of the peoples. With the intensification of its use, the water becomes faced as a finite resource. This is caused by the population growth. As a consequence of the increasing offer of disposable consumption products garbage and industrial solid residues are generated. Destination areas are improvised to the solid residues often without an appropriate infrastructure. Those areas frequently end if turning definitive and generating a series of upsets. Those areas, the landfills, are sources of the element mercury (Hg) that is considered a global pollutant with good mobility, found mainly in the water and aquatics foods, capable to cause dysfunctions in the nervous system leaving the world population in alert constant. This pollution restricts the use of the water, due to environmental problems and damages to the health of the population. In the municipal district of São Pedro da Aldeia, we realized chemical analyses, in water and sediment in a landfill area, measuring the concentration of Hg and some other metals (Fe, Mn and Zn), organic matter, pH, conductivity and sulfide, with the purpose of quantify the concentration of the metals and to study its behavior in the region.
150

Contaminação do solo e das águas subterrâneas por sepultamento de carcaças de animais no solo / Soil and groundwater contamination by burial of animal carcasses on the ground

Yadyr Augusto Figueiredo Filho 11 May 2011 (has links)
Em área classificada como área contaminada sob investigação, de acordo com os processos de investigação de áreas contaminadas da Companhia de Tecnologia de Saneamento Ambiental (CETESB, 2001), no Município de Pirassununga (SP), foi instalado um processo de pesquisa objetivando avaliar possível contaminação do solo e das águas subterrâneas por sepultamento de carcaças de animais no solo. Foram instalados poços de monitoramento que permitiram a coleta de água para análise física, química e microbacteriológica, localizados a partir de sondagens geofísicas e estudos geológicos, geomorfológicos e pedológicos. Os resultados preliminares indicaram forte presença de microorganismos que, de acordo com os índices de potabilidade de águas estipulados pela Agência Nacional de Vigilância Sanitária (ANVISA, 2005) e Ministério da Saúde (2004), implicam impactos ambientais e riscos à saúde pública. A partir de questões surgidas em campo e problemas técnicos encontrados, novas metodologias foram desenvolvidas e aplicadas, tendo, em uma primeira análise, se mostrado bastante eficazes. Essas novas metodologias incluem novos procedimentos de coleta e de acondicionamento e transporte das amostras de água e de solo. Os resultados obtidos nas análises das águas subterrâneas e do solo revelam que há uma expressiva contaminação por uma importante diversidade de microorganismos, alguns muito importantes para a saúde pública, como Salmonella sp e Clostridium perfringens, além de diversidade de outros patógenos de origem fecal. Também foram detectados esporos de bactérias mesófilas anaeróbias e de bactérias mesófilas aeróbias, que podem representar, no caso de contaminação causada por cadáveres de origem animal, patógenos importantes como o Clostridium botulinum e o Bacillus anthracis, que representam risco epidemiológico e morte. Estes dados, interpretados em conjunto com as interpretações pedológicas e climáticas, revelam que há uma notável possibilidade de que esses contaminantes estejam sendo transportados a distâncias consideráveis, para além da área de sepultamento de cadáveres e partes de animais. / In the area classified as contaminated area under investigation, according to the procedures for investigation of contaminated areas of the Technology and Environmental Sanitation Company (CETESB, 2001), in the city of Pirassununga (SP), was installed a research process to evaluate possible soil and groundwater contamination by animal carcasses burial on the ground. Monitoring wells were installed that allowed the collection of water for physics, chemistry and microbacteriological analysis, located from geophysical surveys and geological, geomorphological and soil studies. Preliminary results show a strong presence of microorganisms that, according to the indices of drinking water stipulated by the National Sanitary Surveillance Agency (ANVISA, 2005) and Ministry of Health (2004), indicate environmental impacts and risks to public health. The questions raised in the field and encountered technical problems, new methodologies were developed and implemented, and on a first analysis, proved quite effective. New methodologies include new procedures for collecting and packaging and transportation of water and soil samples. The analysis results of groundwater and soil analysis show that there is significant contamination by a large diversity of microorganisms, some very important public health such as Salmonella and Clostridium perfringens, and diversity of other pathogens of faecal origin. Were also detected spores of mesophilic anaerobic and aerobic mesophilic bacteria, which may represent, in the case of contamination from animal corpses, important pathogens such as Clostridium botulinum and Bacillus anthracis, which represent epidemiological risk and death. These data, interpreted in conjunction with soil and climatic interpretations show that there is a remarkable possibility that these contaminants are being transported considerable distances beyond the area of burial of corpses and animal parts.

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