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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.
131

Imaging the Mechanics of Hydraulic Fracturing in Naturally-fractured Reservoirs Using Induced Seismicity and Numerical Modeling

Zhao, Xueping 05 September 2012 (has links)
The primary objective of this study is to improve understanding of the mechanics of hydraulic fracturing in naturally-fractured reservoirs. The study focuses on enhancing the interpretation of hydraulic fracture-induced microseismic data using an S-wave Gaussian-beam method and numerical modeling techniques for interpretation. The S-wave Gaussian-beam method was comprehensively calibrated by synthetic and real data sets with different recording networks, and this showed the potential to retrieve additional microseismic data from hydraulic fracturing with linear receiver arrays. This approach could enhance current practice because a large number of induced events in these environments have very strong S-waves with P-wave amplitudes similar, or less than, background noise levels. The numerical study using the distinct element methods PFC2D and PFC3D was used to validate the understanding of the hydraulic fracturing mechanisms induced in laboratory and field fluid treatments in naturally-fractured reservoirs. This was achieved through direct comparison with the results of the geometry of hydraulic fractures and seismic source information (locations, magnitudes, and mechanisms) from both laboratory experiments and field observations. A suite of numerical models with fully-dynamic and hydro-mechanical coupling has been used to examine in detail the interaction between natural and induced fractures with the variations of the differential stresses and the orientations of the pre-fractures, and the relationship between the fluid front, the fracture tip, and the induced seismicity. The numerical results qualitatively agreed with the laboratory and field observations of the geometry of hydraulic fractures, confirmed the possible mechanics of new fracture development and their interactions with natural fractures, and illustrated the possible relationship between the fluid front and the fracture tip. The validated model could therefore help track the potential extent of induced fracturing in naturally-fractured reservoirs and the extent to which it can be detected by a microseismic monitoring array in order to assess the effectiveness of a hydraulic fracturing project.
132

Facilitating sense of belonging of children in fractured families from disadvantaged communities utilising bibliotherapeutic techniques / Iralda Oelofsen.

Oelofsen, Iralda January 2012 (has links)
To belong somewhere is a basic human need. It is necessary for the psychological well-being of children to feel that they belong to a family, group and community and that they are loved and appreciated for who they are. A lack of a sense of belonging may cause children to find acceptance and belonging in destructive behaviour or groups. Children from fractured families who live in disadvantaged communities face more challenges than children who have easy access to education, health services and emotional support systems. Caregivers in these circumstances have a daily battle to survive and to keep their children safe. They do not always have the necessary knowledge to be aware of the children’s emotional needs, or the ability and means to fulfil in these needs. Social workers who render services to these families do not always have the time or aids to assist the children to enhance their sense of belonging or to enable the caregivers to strengthen the bond between them and the children. The overall goal of this study was to determine how bibliotherapeutic techniques can be utilised by caregivers and social workers to enhance a sense of belonging in children in their middle childhood years from fractured families in disadvantaged communities. In order to reach this goal, the way in which children from fractured families in disadvantaged communities experienced their sense of belonging was explored, as well as how the children, their caregivers and social workers perceived the social capital in the community. The content of a strategy that focuses on the uses of bibliotherapeutic techniques for children in fractured families from disadvantaged communities in order to enhance their sense of belonging was also determined, as well as ways in which such a strategy could be implemented by the social workers and the caregivers. The research findings suggested that children did not always have a sense of belonging with their primary caregivers and that the caregivers were unaware of the emotional needs of the children. The children expressed a need for playful interactions, nurturing and to listen to stories with their caregivers. Due to the caregivers’ lack of insight in the emotional needs of the children and illiteracy in some cases, a training programme that focussed on the importance of a sense of belonging and practical ways in which they can interact with the children to strengthen the emotional bond between them, was created and tested. The caregivers and children were able to identify schools, neighbours and churches as potential social capital in the community. Ways in which the social capital in the community could be utilised were suggested. Bibliotherapeutic techniques for the use of social workers to enhance a sense of belonging in the children were compiled and then tested by social workers. Both the training program and the bibliotherapeutic techniques proved to be useful and effective and will be disseminated for the use of social workers in their services with children and caregivers in disadvantaged communities. / Thesis (PhD (Social Work))--North-West University, Potchefstroom Campus, 2013.
133

Facilitating sense of belonging of children in fractured families from disadvantaged communities utilising bibliotherapeutic techniques / Iralda Oelofsen.

Oelofsen, Iralda January 2012 (has links)
To belong somewhere is a basic human need. It is necessary for the psychological well-being of children to feel that they belong to a family, group and community and that they are loved and appreciated for who they are. A lack of a sense of belonging may cause children to find acceptance and belonging in destructive behaviour or groups. Children from fractured families who live in disadvantaged communities face more challenges than children who have easy access to education, health services and emotional support systems. Caregivers in these circumstances have a daily battle to survive and to keep their children safe. They do not always have the necessary knowledge to be aware of the children’s emotional needs, or the ability and means to fulfil in these needs. Social workers who render services to these families do not always have the time or aids to assist the children to enhance their sense of belonging or to enable the caregivers to strengthen the bond between them and the children. The overall goal of this study was to determine how bibliotherapeutic techniques can be utilised by caregivers and social workers to enhance a sense of belonging in children in their middle childhood years from fractured families in disadvantaged communities. In order to reach this goal, the way in which children from fractured families in disadvantaged communities experienced their sense of belonging was explored, as well as how the children, their caregivers and social workers perceived the social capital in the community. The content of a strategy that focuses on the uses of bibliotherapeutic techniques for children in fractured families from disadvantaged communities in order to enhance their sense of belonging was also determined, as well as ways in which such a strategy could be implemented by the social workers and the caregivers. The research findings suggested that children did not always have a sense of belonging with their primary caregivers and that the caregivers were unaware of the emotional needs of the children. The children expressed a need for playful interactions, nurturing and to listen to stories with their caregivers. Due to the caregivers’ lack of insight in the emotional needs of the children and illiteracy in some cases, a training programme that focussed on the importance of a sense of belonging and practical ways in which they can interact with the children to strengthen the emotional bond between them, was created and tested. The caregivers and children were able to identify schools, neighbours and churches as potential social capital in the community. Ways in which the social capital in the community could be utilised were suggested. Bibliotherapeutic techniques for the use of social workers to enhance a sense of belonging in the children were compiled and then tested by social workers. Both the training program and the bibliotherapeutic techniques proved to be useful and effective and will be disseminated for the use of social workers in their services with children and caregivers in disadvantaged communities. / Thesis (PhD (Social Work))--North-West University, Potchefstroom Campus, 2013.
134

Finite element method for coupled thermo-hydro-mechanical processes in discretely fractured and non-fractured porous media

Watanabe, Norihiro 26 February 2013 (has links) (PDF)
Numerical analysis of multi-field problems in porous and fractured media is an important subject for various geotechnical engineering tasks such as the management of geo-resources (e.g. engineering of geothermal, oil and gas reservoirs) as well as waste management. For practical usage, e.g. for geothermal, simulation tools are required which take into account both coupled thermo-hydro-mechanical (THM) processes and the uncertainty of geological data, i.e. the model parametrization. For modeling fractured rocks, equivalent porous medium or multiple continuum model approaches are often only the way currently due to difficulty to handle geomechanical discontinuities. However, they are not applicable for prediction of flow and transport in subsurface systems where a few fractures dominates the system behavior. Thus modeling coupled problems in discretely fractured porous media is desirable for more precise analysis. The subject of this work is developing a framework of the finite element method (FEM) for modeling coupled THM problems in discretely fractured and non-fractured porous media including thermal water flow, advective-diffusive heat transport, and thermoporoelasticity. Pre-existing fractures are considered. Systems of discretely fractured porous media can be considered as a problem of interacted multiple domains, i.e. porous medium domain and discrete fracture domain, for hydraulic and transport processes, and a discontinuous problem for mechanical processes. The FEM is required to take into account both kinds of the problems. In addition, this work includes developing a methodology for the data uncertainty using the FEM model and investigating the uncertainty impacts on evaluating coupled THM processes. All the necessary code developments in this work has been carried out with a scientific open source project OpenGeoSys (OGS). In this work, fluid flow and heat transport problems in interactive multiple domains are solved assuming continuity of filed variables (pressure and temperature) over the two domains. The assumption is reasonable if there are no infill materials in fractures. The method has been successfully applied for several numerical examples, e.g. modeling three-dimensional coupled flow and heat transport processes in discretely fractured porous media at the Gross Schoenebck geothermal site (Germany), and three-dimensional coupled THM processes in porous media at the Urach Spa geothermal site (Germany). To solve the mechanically discontinuous problems, lower-dimensional interface elements (LIEs) with local enrichments have been developed for coupled problems in a domain including pre-existing fractures. The method permits the possibility of using existing flow simulators and having an identical mesh for both processes. It enables us to formulate the coupled problems in monolithic scheme for robust computation. Moreover, it gives an advantage in practice that one can use existing standard FEM codes for groundwater flow and easily make a coupling computation between mechanical and hydraulic processes. Example of a 2D fluid injection problem into a single fracture demonstrated that the proposed method can produce results in strong agreement with semi-analytical solutions. An uncertainty analysis of THM coupled processes has been studied for a typical geothermal reservoir in crystalline rock based on the Monte-Carlo method. Fracture and matrix are treated conceptually as an equivalent porous medium, and the model is applied to available data from the Urach Spa and Falkenberg sites (Germany). Reservoir parameters are considered as spatially random variables and their realizations are generated using conditional Gaussian simulation. Two reservoir modes (undisturbed and stimulated) are considered to construct a stochastic model for permeability distribution. We found that the most significant factors in the analysis are permeability and heat capacity. The study demonstrates the importance of taking parameter uncertainties into account for geothermal reservoir evaluation in order to assess the viability of numerical modeling.
135

Hydrogeological investigation of Quaternary and late Cretaceous bedrock aquifers, Comox Coalfield, Vancouver Island, British Columbia, Canada

Fisher, Gypsy C. 30 April 2009 (has links)
This study involved a regional hydrogeological assessment of the Comox Coalfield on Vancouver Island, British Columbia. Two site-specific geological and hydrogeological investigations were conducted. The first involved generating a 2.5 dimensional hydrostratigraphic model of part of the Quadra Sand Comox-Merville Aquifer using lithology information from 196 drilled domestic-use groundwater wells. Well logs were standardized with respect to lithologic and hydraulic characteristics. Contact surfaces were created for identifiable hydrostratigraphic units employing an iterative geostatistical interpolation process that incorporated contact points from well logs and interpreted points based on the regional hydrogeology. Modeled hydrostratigraphic surfaces were compared to logged contacts and to exposures at Willemar and Lazo bluffs at Comox. Six lithostratigraphic units were identified in the coastal exposures. Hydraulic conductivity values, estimated from grain size data using the Hazen method, for the lowermost 4 units were: 2.3 x 10-3 cm/s, 9.1 x 10-6 cm/s, 9.4 x 10-3 cm/s, and 4.7 x 10-6 cm/s, respectively. The hydrostratigraphic model was verified using statistical variance analysis, field reconnaissance data, and the identification of a separate surficial aquifer within the study area. The model identified all units mapped in the field and two units below sea level, inferred to be the Cowichan Head Formation. The Comox Bluff model successfully predicted, within 2 m vertically, subsurface hydrostratigraphic boundaries 80% of the time. The second component of the study included a hydrogeological investigation of stacked Quaternary and Late Cretaceous bedrock aquifers at Oyster River. This investigation incorporated drilling logs, borehole geophysics, aqueous geochemistry, pumping and recovery test data, and hydrostratigraphic interpretation of surficial exposures. The potential for hydraulic communication between the Late Cretaceous Nanaimo Group fractured sedimentary bedrock and the overlying unconsolidated Quaternary aquifers was examined. Two adjacent groundwater observation wells were drilled; one completed in bedrock (146.9 m) and one in the surficial sediments (7.3 m). The deeper well penetrated the Trent River and Comox Formations of the Nanaimo Group. A water-bearing fracture zone approximately 3 m wide was encountered at 135 metres below ground surface, coincident with the Comox Y and Y Lower coal seams. Dissolved methane gas was detected in the bedrock aquifer, with an initial concentration of 2,123 mg/L. Schoeller diagrams reveal that the gas in bedrock is coal related. A pumping and recovery test in the deep well suggests that there is unlikely any hydraulic communication between the bedrock and surficial aquifers encountered at Oyster River. This assessment is based on infrequent water level measurements in the shallow well, which did not consistently draw down during pumping of the deeper well. However, the pumping rate was not sustainable for this test and it could not be held constant. Fracture transmissivity and hydraulic conductivity for the bedrock aquifer were estimated using the Theis Recovery method at 7.06 x 10-7 m2/s and 2.29 x 10-7 m/s, respectively. The hydrogeological research conducted at Comox and Oyster River highlights the effectiveness of a multidisciplinary approach for subsurface investigations. This study contributes site level data upon which regional inferences can be built for the Comox Coalfield.
136

Avaliação da explotação de poços tubulares, no sistema aquífero serra geral, por sistema de monitoramento automatizado

Dutra, Tuane de Oliveira January 2016 (has links)
Carlos Barbosa é um município abastecido exclusivamente por recursos hídricos subterrâneos captados do Sistema Aquífero Serra Geral, sendo o abastecimento de responsabilidade da Companhia Riograndense de Saneamento – CORSAN. Devido a este panorama, o município foi selecionado para instalação do SIGAS que é um sistema de monitoramento totalmente automatizado e com envio de dados por telemetria. O SIGAS foi instalado em 12 dos 15 poços atualmente utilizados para o abastecimento do munícipio e monitora volume e corrente de 15 em 15 minutos e nível de água de 1 em 1 minuto. Este trabalho se propôs a avaliar as condições de explotação em 8 dos 12 poços monitorados por este sistema, os quais abastecem, juntamente com outros 4 poços 3 dos 4 reservatórios existentes no município. Logo, foram comparados os dados diários de volume, vazão e tempo de bombeamento coletados pelo SIGAS com os valores definidos quando da elaboração dos projetos de bombeamento. Para verificação dos dados coletados pelo SIGAS foi realizada uma comparação com os dados coletados pela CORSAN e com os dados obtidos em levantamentos de campo. Os poços CBA 3A, 5A, 9, 11 e 12, na maior parte do tempo, operaram com vazão inferior a projetada, sendo que o oposto ocorreu nos poços CBA 18, 26 e 34. O tempo de bombeamento operado se manteve acima do projetado, na maior parte do tempo, nos poços CBA 3A, 9, 12 e 18, sendo que o inverso ocorreu nos poços CBA 5A, 11, 26 e 34. O volume médio de água explotado ficou acima do previsto em projeto, na maior parte do tempo, apenas nos poços CBA 18 e 26. Os resultados demostraram que há falhas na gestão e no planejamento da operação dos poços, sendo que há poços explotando volumes de água acima do permitido, enquanto em outros o volume explotado está abaixo do projetado. Foi identificado também a influência da demanda na operação dos poços, as quais tornam o tempo de descanso descontínuo dificultando a recuperação do nível de água no poço. Os dados coletados pelo SIGAS se demostraram confiáveis e coerentes com os valores operados nos poços, sendo assim os mesmos poderão ser utilizados na gestão e planejamento da operação dos poços no município de Carlos Barbosa. / Carlos Barbosa is a city supplied exclusively by groundwater resources obtained from the Serra Geral Aquifer System, and the supplying responsibility is from the Companhia Riograndense de Saneamento - CORSAN. Because of this panorama, the city was selected for the installation of SIGAS, which is a fully automated monitoring system and sending data by telemetry. The SIGAS was installed in 12 of the 15 wells currently used to supply the city and it monitors volume and current 15 in 15 minutes and water level 1 in 1 minute. This study aimed to evaluate the exploitation conditions in 8 of the 12 wells that the system has, which supply, along with other 4 wells, 3 of the 4 existing reservoirs in the city. Then, were compared the daily volume of data, flow and pumping time collected by SIGAS with the values defined during the preparation of pumping projects. For verification of the data collected by SIGAS a comparison with the data collected by CORSAN and with data from field surveys were fulfilled. The wells CBA 3A, 5A, 9, 11 and 12, at the most part of the time, operated at a flow below of projected, being that the opposite was observed in the wells CBA 18, 26 and 34. The operated pumping time is kept above the projected, at the most part of the time, in the wells CBA 3A, 9, 12 and 18, being that the converse occurred in the wells CBA 5A, 11, 26 and 34. The average volume of exploited water was above the provided in project, at the most part of the time, only in the wells CBA 18 and 26. The results showed that there are flaws in the management and planning of the operation of the wells, being that there are wells exploring volumes above the allowed, while in others the exploited volume is below the projected. It was also identified the influence demand in the operation of wells, which make the discontinuous rest time hindering the recovery of the water level in the well. The data collected by SIGAS been shown reliable and coherent with the values operated in the wells, so the same might be used in the management and planning of the operation of the wells in the city of Carlos Barbosa.
137

Identificação e caracterização de zonas de captura e concentração de águas subterrâneas a partir de produtos de sensoriamento remoto

Coelho, Juliano Oliveira Martins [UNESP] 01 July 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-01Bitstream added on 2014-06-13T19:54:12Z : No. of bitstreams: 1 coelho_jom_me_rcla.pdf: 20177455 bytes, checksum: 64e50fac6a92d2bdb635716d559dac70 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os aqüíferos subterrâneos são reservas estratégicas de recursos hídricos, devendo haver um planejamento adequado para o seu uso e conservação. As zonas de recarga e de concentração de água subterrânea são de suma importância na dinâmica dos sistemas aqüíferos, sendo responsáveis, respectivamente, pelo reabastecimento e pelo armazenamento do recurso. Técnicas de fotointerpretação a partir de produtos de sensoriamento remoto podem ser muito úteis aos estudos hidrológicos, fornecendo informações relevantes a respeito do meio físico, principalmente em escala de reconhecimento. Assim, esta pesquisa tem como objetivo identificar e caracterizar as zonas de captura e concentração de águas subterrâneas em rochas cristalinas, a partir de técnicas de fotointerpretação em produtos de sensoriamento remoto. Para tal, foram estabelecidas unidades geoambientais, a partir da compartimentação do meio físico e posterior classificação de suas propriedades geotécnicas, e foi realizado também um mapeamento morfoestrutural de feições rúpteis e dúcteis. A combinação do Mapa de Unidades Geoambientais e do Mapa Morfoestrutural resultou no Mapa de Zonas de Captura e Concentração de Águas Subterrâneas, onde a convergência de evidências favoráveis à infiltração, percolação e concentração de águas indica as potenciais zonas de recarga, circulação e concentração de águas subterrâneas, colaborando com a prospecção e com o planejamento do uso deste recurso. As principais zonas de recarga e de concentração de recursos hídricos identificadas pelo mapeamento foram o Alto Estrutural de Natividade da Serra, potencialmente uma excelente zona de recarga, e o Baixo Estrutural de Lagoinha/São Luis do Paraitinga, com grande potencial à concentração de recursos hídricos. Estudos de maior detalhe nas áreas potenciais identificadas pelo mapeamento podem confirmar... / The fractured aquifers are strategic reserves of water resources, and there should be proper planning for its use and conservation. Areas of concentration and recharge of groundwater is of paramount importance in the dynamics of aquifer systems, responsible respectively for storage and replenishment of the resource. Photointerpretation techniques from remote sensing products can be very useful for hydrological studies, providing relevant information about the physical environment, especially in wide recognition. Thus, this research aims to identify and characterize areas of capture and concentration of groundwater in crystalline rocks, from photointerpretation techniques in remote sensing products. For such geoenvironmental units were established from the partitioning of the physical environment and subsequent classification of their geotechnical properties, and was also performed a morphostructural mapping of brittle and ductile features. The combination of the Geoenvironmental Units Map and the Morphostructural Map resulted in the Groundwater Capture and Concentration Map, where the convergence of evidence favorable to infiltration, percolation and water concentration indicates potential areas of recharge, movement and concentration of groundwater, collaborating with the prospecting and planning of the use of this resource. The main areas of recharge and concentration of water resources were identified by mapping the High Structural of Natividade Sierra, potentially an excellent recharge area, and the Lower Structural of Lagoinha/São Luis do Paraitinga, with great potential to the concentration of water resources. Studies in greater detail of the potential areas identified by the mapping can confirm whether or not the presence of water resource, directing the actions of environmental planning and exploitation of water
138

Shape Factors for the Pseudo-Steady State Flow in Fractured Hydrocarbon Wells of Various Drainage Area Geometries

January 2017 (has links)
abstract: Pseudo-steady state (PSS) flow is an important time-dependent flow regime that quickly follows the initial transient flow regime in the constant-rate production of a closed boundary hydrocarbon reservoir. The characterization of the PSS flow regime is of importance in describing the reservoir pressure distribution as well as the productivity index (PI) of the flow regime. The PI describes the production potential of the well and is often used in fracture optimization and production-rate decline analysis. In 2016, Chen determined the exact analytical solution for PSS flow of a fully penetrated vertically fractured well with finite fracture conductivity for reservoirs of elliptical shape. The present work aimed to expand Chen’s exact analytical solution to commonly encountered reservoirs geometries including rectangular, rhomboid, and triangular by introducing respective shape factors generated from extensive computational modeling studies based on an identical drainage area assumption. The aforementioned shape factors were generated and characterized as functions for use in spreadsheet calculations as well as graphical format for simplistic in-field look-up use. Demonstrative use of the shape factors for over 20 additional simulations showed high fidelity of the shape factor to accurately predict (mean average percentage error remained under 1.5 %) the true PSS constant by modulating Chen’s solution for elliptical reservoirs. The methodology of the shape factor generation lays the ground work for more extensive and specific shape factors to be generated for cases such as non-concentric wells and other geometries not studied. / Dissertation/Thesis / Masters Thesis Chemical Engineering 2017
139

Avaliação da explotação de poços tubulares, no sistema aquífero serra geral, por sistema de monitoramento automatizado

Dutra, Tuane de Oliveira January 2016 (has links)
Carlos Barbosa é um município abastecido exclusivamente por recursos hídricos subterrâneos captados do Sistema Aquífero Serra Geral, sendo o abastecimento de responsabilidade da Companhia Riograndense de Saneamento – CORSAN. Devido a este panorama, o município foi selecionado para instalação do SIGAS que é um sistema de monitoramento totalmente automatizado e com envio de dados por telemetria. O SIGAS foi instalado em 12 dos 15 poços atualmente utilizados para o abastecimento do munícipio e monitora volume e corrente de 15 em 15 minutos e nível de água de 1 em 1 minuto. Este trabalho se propôs a avaliar as condições de explotação em 8 dos 12 poços monitorados por este sistema, os quais abastecem, juntamente com outros 4 poços 3 dos 4 reservatórios existentes no município. Logo, foram comparados os dados diários de volume, vazão e tempo de bombeamento coletados pelo SIGAS com os valores definidos quando da elaboração dos projetos de bombeamento. Para verificação dos dados coletados pelo SIGAS foi realizada uma comparação com os dados coletados pela CORSAN e com os dados obtidos em levantamentos de campo. Os poços CBA 3A, 5A, 9, 11 e 12, na maior parte do tempo, operaram com vazão inferior a projetada, sendo que o oposto ocorreu nos poços CBA 18, 26 e 34. O tempo de bombeamento operado se manteve acima do projetado, na maior parte do tempo, nos poços CBA 3A, 9, 12 e 18, sendo que o inverso ocorreu nos poços CBA 5A, 11, 26 e 34. O volume médio de água explotado ficou acima do previsto em projeto, na maior parte do tempo, apenas nos poços CBA 18 e 26. Os resultados demostraram que há falhas na gestão e no planejamento da operação dos poços, sendo que há poços explotando volumes de água acima do permitido, enquanto em outros o volume explotado está abaixo do projetado. Foi identificado também a influência da demanda na operação dos poços, as quais tornam o tempo de descanso descontínuo dificultando a recuperação do nível de água no poço. Os dados coletados pelo SIGAS se demostraram confiáveis e coerentes com os valores operados nos poços, sendo assim os mesmos poderão ser utilizados na gestão e planejamento da operação dos poços no município de Carlos Barbosa. / Carlos Barbosa is a city supplied exclusively by groundwater resources obtained from the Serra Geral Aquifer System, and the supplying responsibility is from the Companhia Riograndense de Saneamento - CORSAN. Because of this panorama, the city was selected for the installation of SIGAS, which is a fully automated monitoring system and sending data by telemetry. The SIGAS was installed in 12 of the 15 wells currently used to supply the city and it monitors volume and current 15 in 15 minutes and water level 1 in 1 minute. This study aimed to evaluate the exploitation conditions in 8 of the 12 wells that the system has, which supply, along with other 4 wells, 3 of the 4 existing reservoirs in the city. Then, were compared the daily volume of data, flow and pumping time collected by SIGAS with the values defined during the preparation of pumping projects. For verification of the data collected by SIGAS a comparison with the data collected by CORSAN and with data from field surveys were fulfilled. The wells CBA 3A, 5A, 9, 11 and 12, at the most part of the time, operated at a flow below of projected, being that the opposite was observed in the wells CBA 18, 26 and 34. The operated pumping time is kept above the projected, at the most part of the time, in the wells CBA 3A, 9, 12 and 18, being that the converse occurred in the wells CBA 5A, 11, 26 and 34. The average volume of exploited water was above the provided in project, at the most part of the time, only in the wells CBA 18 and 26. The results showed that there are flaws in the management and planning of the operation of the wells, being that there are wells exploring volumes above the allowed, while in others the exploited volume is below the projected. It was also identified the influence demand in the operation of wells, which make the discontinuous rest time hindering the recovery of the water level in the well. The data collected by SIGAS been shown reliable and coherent with the values operated in the wells, so the same might be used in the management and planning of the operation of the wells in the city of Carlos Barbosa.
140

Tectônica rúptil aplicada ao estudo de aqüífero em rochas cristalinas fraturadas na região de Cotia, SP / Brittle tectonics applyed to study of crystalline fractured-bedrock aquifer in Cotia, SP region

Fernando Machado Alves 19 August 2008 (has links)
O estudo da hidrogeologia em aqüífero cristalino fraturado apresenta como maior desafio a imprevisibilidade do meio, uma vez que o fluxo ocorre exclusivamente pelas fraturas. Neste sentido informações de atitude, abertura e conectividade de fraturas tornam-se essenciais no entendimento do fluxo da água subterrânea. O presente trabalho busca aplicar o conhecimento da tectônica rúptil para caracterizar o meio fraturado, com intuito de auxiliar o estudo hidrogeológico do aqüífero. A área de estudo está localizada na porção leste do Município de Cotia, SP, no contexto do Complexo Embu, de idade proterozóica, na porção central da Faixa Ribeira. Ocorrem predominantemente rochas granitóides, com permeabilidade primária desprezível, rochas cataclásticas relacionadas às grandes zonas de cisalhamento de Taxaquara e Caucaia do Alto, metassedimentos e coberturas aluviais cenozóicas, estas ao longo das principais drenagens. Os principais eventos tectônicos de caráter rúptil da região estiveram relacionados à reativação mesozóico-cenozóica, inicialmente com a ruptura continental e abertura do Oceano Atlântico Sul e, posteriormente, a formação do Rift Continental do Sudeste do Brasil (RCSB), e seus principais eventos de deformação. Os estudos foram desenvolvidos em duas escalas de trabalho. A primeira de semi-detalhe, em 1:50.000, e a segunda de detalhe, em 1:5.000, esta última em duas porções distintas dentro da área de semi-detalhe. Os resultados obtidos em escala de semi-detalhe, a partir da análise da tectônica rúptil (morfometria, fotogeologia e levantamentos de campo), serviram para direcionar as investigações em escala de detalhe, onde foram usados dados provenientes de sondagens, métodos BHTV (Bore Hole Television), levantamento de perfis de eletrorresistividade e dados hidrogeológicos de poços de monitoramento instalados no aqüífero em meio fraturado. Os estudos de escala de semi-detalhe permitiram delinear lineamentos de direções N-S, E-W, NE-SW e NW-SE, originados pelas diversas fases de deformação rúptil. Esses dados de lineamentos foram correlacionados com dados de atitude de falhas e juntas medidas em afloramento, e, posteriormente, associados às diferentes fases de deformação descritas para o RCSB. Foram definidas seis famílias de juntas: a) família NNW-SSE, com mergulho alto para NE); b) família NE-SW com mergulho sub-vertical; c) família E-W com mergulho alto para NW); d) família WNW-ESE com mergulho alto para NE); e) família NESW com mergulho médio para NW; e f) família NE-SW com mergulho médio para SE. Os resultados dos estudos desenvolvidos em escala de semi-detalhe, somados aos condicionantes geológicos e geomorfológicos das áreas selecionadas para estudos de detalhe, orientaram a instalação de poços de monitoramento verticais e inclinados nessas últimas. Foram instalados 11 poços na área de detalhe A e quatro poços na área de detalhe B. Os poços foram perfilados por televisionamento acústico e as fraturas identificadas nesses poços foram separadas por famílias e subfamílias: Família 1 (sub-horizontal), Família 2A (N-S com mergulho médio para W) e 2B (N-S com mergulho alto para E), Família 3A (NE-SW com mergulho médio para NW) e 3B (NE-SW com mergulho médio para SE) e Família 4 (WNW-ESE sub-vertical). Na maioria dos poços foram realizados ensaios hidráulicos para determinação da condutividade hidráulica (K), que variou de 1,55x10-8 a 2x10-5 cm/s, com média de 2,98x10-6 e desvio padrão de 5,60 x10-6 cm/s. Ensaios de bombeamento indicaram fluxo de água subterrânea através das estruturas N-S, com boa conexão com as estruturas NE-SW. A abertura média das fraturas foi de 1,13x10-3 cm, calculada com base nos valores de condutividade hidráulica correlacionados aos dados estruturais. A partir dos dados hidrogeológicos e estruturais foi proposto um método para se estimar a transmissividade e condutividade hidráulica de um poço instalado no aqüífero fraturado. / The main challenge in a hydrogeological study of a fractured-bedrock aquifer is the unpredictability of media, because the ground-water flows only through the fractures. Informations about strike, dip, opening and connectivity among fractures become essential in order to understand the ground-water flow. This work is an application of the concepts of the brittle tectonics to characterize a fractured media in order to help the hydrogeological study of a fractured-bedrock aquifer. The study area is located at the eastern part of the City of Cotia, State of São Paulo, Southeastern Brazil, in the context of the Proterozoic Embu Complex, in the central part of Ribeira Belt. This area encompass predominantly granitoid rocks (with negligible primary permeability), cataclastic rocks related to the Taxaquara and Caucaia do Alto shear zones, and metasedimentary rocks. Quaternary alluvial deposits occur along the main drainages. The main brittle tectonic events in the region are related to the Mesozoic-Cenozoic reactivation, associated with the continental break-up, the opening of the South Atlantic Ocean, and the formation and deformation of the basins of the Continental Rift of the Southeastern Brazil (CRSB). The study was carried out in two working scales. First in a semi-detail scale, at 1:50,000, of a large area, were brittle tectonic analysis (morphometry, photogeology and field survey in outcrops) was performed. The achieved results were used to select two small areas, within the semi-detail area, for a detailed investigation, on scale of 1:5,000, in which data from rock-boring, BHTV (Bore Hole Television), eletroresistivity and hydrogeology from bedrock monitoring wells were obtained. At a semi-detail scale it was possible to delineate lineaments of N-S, E-W, NE-SW and NW-SE-trending directions, probably originated during several brittle deformational events. Data from lineaments were first correlated with data of fault and joint measured in outcrops and latterly associated with different deformation phases described in CRSB. Six joint families were defined: a) steeply northeastward dipping NNW-SSE-trending family; b) sub-vertically dipping NE-SW trending family; c) steeply northwestward dipping E-W-trending family; d) steeply northeastward dipping WNW-ESE-trending family); e) NE-SW-trending family with moderate dipping towards the NW; and f) NE-SW-trending family with moderate dipping towards the SE. Results of studies in the semi-detail investigation area allowed the selection of sites for drilling of 11 wells in detail area A and 4 wells in the detail area B. All the wells were surveyed by acoustic teleview and the identified fractures were classified in four families and two subfamilies: family 1 (sub-horizontal to gently dipping); family 2A (N-S-trending with moderate dipping towards the W) and 2B (NS-trending with steep dipping towards the E); family 3A (NE-SW-trending with moderate dipping towards the NW) and 3B (NE-SW-trending with moderate dipping towards the SE); and family 4 (WNW-ESE-trending with sub-vertical dipping). Hydraulic conductivity (K) measured in the wells ranged from 1.55x10-8 to 2x10-5 cm/s, with a mean of 2.98x10-6 and standard deviation of 5.60 x10-6 cm/s. Pumping tests showed the groundwater flow through N-S-trending structures and good connection with NE-SW-trending structures. The average opening of fractures attained 1.13x10-3 cm and was calculated on the basis of the amount of hydraulic conductivity correlated with structural data. Based on structural and hydrogeological data it was proposed a method for estimating the transmissivity and hydraulic conductivity of a well installed in the fractured-bedrock aquifer.

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