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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.
1

Estudo hidrogeoquímico da porção meridional do sistema aquífero Bauru no estado de São Paulo

Barison, Marcelo Ribeiro [UNESP] 31 July 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-07-31Bitstream added on 2014-06-13T18:43:24Z : No. of bitstreams: 1 barison_mr_dr_rcla.pdf: 3356431 bytes, checksum: 58f1ed72dcf29e8c85ef8149d9a72b2e (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O Sistema Aqüífero Bauru é representado por sedimentos cretáceos do Grupo Bauru e constitui uma das principais fontes de exploração de água subterrânea do Estado de São Paulo. A área de estudo limita-se ao norte pelo rio Tietê, a oeste pelo rio Paraná, a sul pelo rio Paranapanema e a leste pelos litotipos da Formação Serra Geral. O presente trabalho tem como objetivo o estudo hidrogeoquímico das águas subterrâneas do Sistema Aqüífero Bauru utilizando-se conhecimentos de geoquímica de baixa temperatura e isotópica. Para a caracterização dos tipos de rochas existentes e sua evolução diagenética, foram realizadas análises petrográficas, de difratometria de Raios X e de Microscopia Eletrônica de Varredura (MEV Ambiental). A análise hidroquímica identificou a predominância de águas bicarbonatadas cálcicas e calco-magnesianas e secundariamente por águas bicarbonatadas sódicas. Algumas poucas foram classificadas como águas cloretadas. Os resultados isotópicos de 2H e de 18O mostram que as águas subterrâneas são de origem meteórica. A modelagem geoquímica foi executada com a utilização do programa SOLMINEQ88 pc/shell, versão 0.85, conforme proposto por PERKINS, GUNTER & NESBITT (1988) para a obtenção de cálculos de especiação das fases aquosas e do estado de saturação das fases minerais. No estudo da interação rocha-fluido, obteve-se que os arenitos que constituem o Grupo Bauru exerceram grande influência nos tipos hidroquímicos encontrados. Reações de substituição e de hidrólise de silicatos, dissolução de carbonatos e de outros minerais encontrados nos poros dos arenitos, como a analcima e a paligorskita, auxiliaram na incorporação de determinados tipos iônicos pelas águas do sistema aqüífero. / The Bauru Aquifer System is represented by cretaceous sediments from Bauru Group and constitutes one of the main groundwater exploration sources from São Paulo State. The study area is limited to the north by Tietê river, to the west by Paraná river, to the south by Parapanema river and to the east by rocks of Serra Geral Formation. The present research aims to study the hydrogeochemistry behaviour of groundwaters from Bauru Aquifer System using the knowledge of isotopic and low temperature geochemistry. To the characterization of rocks and their diagenetic evolution, petrographic, X-ray difractometry and scan electronic microscope (SEM) analysis have been executed. To hydrochemical analysis revealed mainly calcium bicarbonate and calcium-magnesium bicarbonate waters composition in the study area. Other water samples are sodium bicarbonate and a few ones are chlorinated waters. The isotopic results of 2H and 18O revealed meteoric origin for the groundwaters. The geochemistry modeling was executed using the SOLMINEQ88 pc shell program, version 0.85 (PERKINS, GUNTER & NESBITT, 1988) to obtain the speciation calculus of aqueous phases and the saturation state of mineral phases. The rock-fluid interaction study showed that the sandstones from Bauru Group influenced in the hydrochemistry types found. Silicate dissolution and hydrolysis reactions, carbonate dissolution and the filling of other minerals in the sandstones pores (analcima and palygorkskite), are responsible for the incorporation of determinate ionic concentrations by the waters from aquifer system.
2

Baseline hydrogeochemistry and connectivity among landscape units of two wetland-rich Boreal sites in the Athabasca Oil Sands Region, Alberta

Kusel, Caren 21 May 2014 (has links)
Developing critical loads for nitrogen (N) in the Athabasca Oil Sands Region (AOSR) requires an understanding of the hydrological connectivity and potential for N transport among uplands, fens and bogs typical in the wetland-rich Boreal region of northern Alberta. The Cumulative Environmental Management Association’s (CEMA) overarching mandate is to determine a nitrogen critical load specific to the Boreal region of northern Alberta. To this end, nitrogen amendment experiments were initiated at two Boreal wetland sites: an upland – rich fen gradient at Jack Pine High (JPH) and an upland – fen – bog mosaic at Mariana Lakes (ML), 45 km north and 100 km south of Fort McMurray respectively. The objectives of this study are to use geochemical and isotopic tracers to describe baseline hydrogeochemical variability and connectivity between bog, fens and upland areas in the AOSR. Sites were instrumented with piezometer nests and water table wells along transects that cover the targeted landscape units (n = 108 sampling locations). Fieldwork related to this thesis was conducted during the open-water season: in June and August 2011, and in May, July, and September 2012. Field campaigns also included a snow survey (March 2012), and spring melt/freshet sampling (April 2012). The analysis of spatiotemporal variability of water isotopes and geochemistry in the years 2011-2012 yielded: i) a characterization of baseline conditions from which perturbations can be assessed, and ii) evidence of connectivity among landscape units. No evidence for elevated concentrations of nitrogen related to the amendment experiments was found in 2011 or 2012. The baseline characterization and annual monitoring did show increasing concentrations of inorganic ammonium with increasing depth associated with increasing solute concentrations: average concentrations of inorganic ammonium were 23 mg/L at deepest sampling locations (7 m) at ML bog and ML fen landscape units. These ammonium concentrations in porewaters, given a porosity of 0.90 for peatlands, constitute a store of ammonium that may be a significant source of nitrogen if the hydrology is altered due to co-occurring changes in vegetation (due to, for example, elevated nitrogen inputs), climate and/or landuse. Hydrologic connectivity at JPH is likely driven by topography. Hydraulic head in 2011 and 2012 field seasons showed that flow persisted from the upland to the fen. The consistent and distinct geochemical signatures and isotopic labelling of mid-depth and deep groundwater samples of fen and upland landscape units is consistent with such a stable groundwater continuum. Near-surface water samples at JPH fen however varied hydrogeochemically in response to seasonal changes in precipitation inputs, water levels, and biogeochemical productivity. At ML, hydrological connectivity is a function of antecedent moisture conditions (which determines run-off) and low and variable (10-6 to 10-9 m/s) hydrological conductivity of the peatland substrate (which may result in lateral flow where hydraulic head shows potential for vertical re- or discharge). Near-surface samples showed greater temporal than spatial variability as snowmelt inputs, variations in antecedent moisture conditions and seasonal changes in biogeochemical process rates affected nutrient and solute concentrations. In contrast, shallow, mid-depth and deep samples showed greater spatial than temporal variability. The spatial distributions of parameters could be associated to some degree with vegetation, distance along a surficial flowpath, or depth to mineral substrate or distance from the upland/edge transition. / Graduate / 0996 / 0388 / 0425 / cbkusel@yahoo.ca
3

Baseline hydrogeochemistry and connectivity among landscape units of two wetland-rich Boreal sites in the Athabasca Oil Sands Region, Alberta

Kusel, Caren 21 May 2014 (has links)
Developing critical loads for nitrogen (N) in the Athabasca Oil Sands Region (AOSR) requires an understanding of the hydrological connectivity and potential for N transport among uplands, fens and bogs typical in the wetland-rich Boreal region of northern Alberta. The Cumulative Environmental Management Association’s (CEMA) overarching mandate is to determine a nitrogen critical load specific to the Boreal region of northern Alberta. To this end, nitrogen amendment experiments were initiated at two Boreal wetland sites: an upland – rich fen gradient at Jack Pine High (JPH) and an upland – fen – bog mosaic at Mariana Lakes (ML), 45 km north and 100 km south of Fort McMurray respectively. The objectives of this study are to use geochemical and isotopic tracers to describe baseline hydrogeochemical variability and connectivity between bog, fens and upland areas in the AOSR. Sites were instrumented with piezometer nests and water table wells along transects that cover the targeted landscape units (n = 108 sampling locations). Fieldwork related to this thesis was conducted during the open-water season: in June and August 2011, and in May, July, and September 2012. Field campaigns also included a snow survey (March 2012), and spring melt/freshet sampling (April 2012). The analysis of spatiotemporal variability of water isotopes and geochemistry in the years 2011-2012 yielded: i) a characterization of baseline conditions from which perturbations can be assessed, and ii) evidence of connectivity among landscape units. No evidence for elevated concentrations of nitrogen related to the amendment experiments was found in 2011 or 2012. The baseline characterization and annual monitoring did show increasing concentrations of inorganic ammonium with increasing depth associated with increasing solute concentrations: average concentrations of inorganic ammonium were 23 mg/L at deepest sampling locations (7 m) at ML bog and ML fen landscape units. These ammonium concentrations in porewaters, given a porosity of 0.90 for peatlands, constitute a store of ammonium that may be a significant source of nitrogen if the hydrology is altered due to co-occurring changes in vegetation (due to, for example, elevated nitrogen inputs), climate and/or landuse. Hydrologic connectivity at JPH is likely driven by topography. Hydraulic head in 2011 and 2012 field seasons showed that flow persisted from the upland to the fen. The consistent and distinct geochemical signatures and isotopic labelling of mid-depth and deep groundwater samples of fen and upland landscape units is consistent with such a stable groundwater continuum. Near-surface water samples at JPH fen however varied hydrogeochemically in response to seasonal changes in precipitation inputs, water levels, and biogeochemical productivity. At ML, hydrological connectivity is a function of antecedent moisture conditions (which determines run-off) and low and variable (10-6 to 10-9 m/s) hydrological conductivity of the peatland substrate (which may result in lateral flow where hydraulic head shows potential for vertical re- or discharge). Near-surface samples showed greater temporal than spatial variability as snowmelt inputs, variations in antecedent moisture conditions and seasonal changes in biogeochemical process rates affected nutrient and solute concentrations. In contrast, shallow, mid-depth and deep samples showed greater spatial than temporal variability. The spatial distributions of parameters could be associated to some degree with vegetation, distance along a surficial flowpath, or depth to mineral substrate or distance from the upland/edge transition. / Graduate / 0996 / 0388 / 0425 / cbkusel@yahoo.ca
4

Hydrogeochemistry and hydrology of a basalt aquifer system, the Atherton Tablelands, North Queensland

Locsey, Katrina L. January 2004 (has links)
The Atherton Tablelands basalt aquifer is a major source of groundwater supply for irrigation and other agricultural use. The Tertiary to Quaternary age basaltic aquifer can be regarded as a generally unconfined, layered system, comprising numerous basalt flows separated by palaeo-weathering surfaces and minor alluvial gravels of palaeo-drainage channels. Layers of massive basalt and clay-rich weathered zones act as local aquitards, with some local perched aquifers also present. The aquifer is regarded as a system in which several factors interact to produce the overall characteristics of the hydrogeochemistry of the groundwaters. They include the mineralogical composition of both the basalt aquifer and the thick overlying weathered zone, the porosity and permeability of the basalt aquifer, its thickness, bedrock composition, and climate and topography. The hydrogeochemical processes operating in this aquifer system have been investigated though the analysis of 90 groundwater samples collected from October 1998 to October 1999, groundwater chemistry data provided by the Queensland Department of Natural Resources & Mines for more than 800 groundwater samples, rain water samples collected during 1999 by CSIRO, stream chemistry data provided by CSIRO and James Cook University, and mineralogical and whole rock geochemistry data of drill chip samples. The methods used in this research study include the assessment of groundwater major ion chemistry data and field physico-chemical parameters using hydrochemical facies and statistical approaches, investigation of the mineralogical composition of the aquifer, assessment of concentrations and activities of the ions in solution, the degree of saturation with respect to both primary and secondary minerals, and hydrogeochemical modelling to determine the likely controls on the chemical evolution of these groundwaters. The basaltic groundwaters are mostly Mg-Ca-Na, HCO3 type waters, with electrical conductivities generally less than 250 μS/cm and pH values from 6.5 to 8.5. Dissolved silica (H4SiO4) comprises a large proportion of the total dissolved load, with average concentrations of around 140 mg/L. Concentrations of potassium, chloride and sulphate are low, that is, generally less than 3 mg/L, 15 mg/L and 10 mg/L, respectively. Despite the very low salinity of the Atherton Tablelands basalt groundwaters, the relative concentrations of the major ions are comparable to groundwaters from other basaltic regions, and are consistent with expected waterrock interactions. A variety of multivariate statistical techniques may be used to aid in the analysis of hydrochemical data, including for example, principal component analysis, factor analysis and cluster analysis. Principal component factor analyses undertaken using the hydrochemical data for the Atherton groundwaters has enabled the differentiation of groundwaters from various lithological formations, the underlying geochemical processes controlling groundwater composition in the basalt aquifer to be inferred, relative groundwater residence and flow directions to be inferred and mapping of the estimated thickness of the basalt aquifer. The limitations of multivariate statistical methods have been examined, with emphasis on the issues pertinent to hydrochemical data, that is, data that are compositional and typically, non-normally distributed. The need to validate, normalize and standardize hydrochemical data prior to the application of multivariate statistical methods is demonstrated. Assessment of the saturation states of the Atherton basalt groundwaters with respect to some of the primary minerals present indicate that the groundwaters are mostly at equilibrium or saturated with respect to K-feldspar, and approach equilibrium with respect to the plagioclase feldspars (albite and anorthite) with increasing pH. These groundwaters are at equilibrium or saturated with respect to the major secondary minerals, kaolinite, smectite (Ca-montmorillonite) and gibbsite. They also tend to be saturated with respect to the oxidation products, goethite and hematite, common accessory minerals in the Atherton Tablelands basalt sequence. Silicate mineral weathering processes are the predominant influence on the composition of these basalt groundwaters. These weathering processes include the weathering of pyroxenes, feldspars and other primary minerals to clays, aluminium and iron oxides, amorphous or crystalline silica, carbonates and zeolites, releasing ions to solution. The contribution of substantial organic carbon dioxide to the groundwater is an important factor in the extent to which silicate mineral weathering occurs in this aquifer system. Evaporative enrichment of recharging waters, oxidation and ion-exchange reactions and the uptake of ions from, and decomposition of, organic matter, are processes that have a minor influence on the composition of the basalt groundwaters. The relationships observed between mineralogical compositions, basalt character and groundwater occurrence in the Atherton Tablelands region improved the understanding how groundwater is stored and transmitted in this basalt aquifer system. Groundwater is mostly stored in vesicular basalt that may be fresh to highly weathered, and movement of this water is facilitated by pathways through both vesicular and fractured basalt. Related work undertaken as part of this research project showed that the groundwater flow patterns defined by the hydrogeochemical interpretations correspond well with the spatial trends in water level fluctuations, and response to recharge events in particular. Groundwater baseflow to streams and discharge to topographic lows in the Atherton Tablelands region is indicated by the relationships between the major cations and anions in the stream waters. Fracture zones are likely to be preferred pathways of groundwater movement. Recharge estimates, based on a chloride mass balance, range from 310 mm/yr in the north-western part of the study area (north of Atherton) to 600 mm/yr in the wetter southern and eastern parts of the study area. These recharge estimates should be treated with caution however, due to the low groundwater chloride concentrations and the high variability in rainfall chloride concentrations. The findings of this research project have improved the understanding of the hydrogeochemical processes controlling the composition of the low salinity basalt groundwaters in the Atherton Tablelands region, and are applicable to other basalt groundwater systems, particularly those in high rainfall environments.
5

Caracterização hidrogeoquímica dos sistemas aquíferos Bauru e Guarani no município de Bauru /

Silva, Sueli Roberta da. January 2009 (has links)
Orientador: Chang Hung Kiang / Banca: Reginaldo Bertolo / Banca: Didier Gastmans / Resumo: Os Sistemas Aquíferos Bauru e Guarani, na área urbana do município de Bauru, apresentam-se em contato direto, diferentemente do que ocorre na maior parte da porção centro-oeste do estado de São Paulo, em que o Aquífero Serra Geral está entre eles. A partir da caracterização hidroquímica dos aquíferos, foi verificado que as águas do SAB são predominantemente ácidas e bicarbonatadas cálcicas, com provável dissolução de carbonatos e monossialitização de feldspatos, enquanto que as do SAG apresentam-se predominantemente básicas, bicarbonatadas sódicas, com provável precipitação de carbonatos e reações de troca catiônica. As concentrações de nitrato e cloreto apresentam-se maiores na porção central da área de estudo, e são características de influência antrópica. Em dois poços do SAG, as concentrações de cálcio, nitrato e cloreto são maiores e o valor de pH é menor que nas demais amostras deste aquífero; estes valores são similares aos obtidos para as águas do SAB; o que é sugestivo de conexão entre os dois aquíferos. No entanto, considerando que nestes poços a espessura do SAG na seção filtrante é menor, é provável que a mistura das águas dos dois sistemas aquíferos esteja ocorrendo dentro do próprio poço, devido suas características construtivas / Abstract: The Guarani Aquifer System (SAG) and Bauru Aquifer System (SAB), in Bauru urban area, São Paulo state, are in direct contact, differently from what occurs in São Paulo state center-west, where the Serra Geral Aquifer is between them. The aquifer hydrogeochemistry characterization of the SAB had been shown that groundwater are predominantly acid and calcium-bicarbonate type, probable related to carbonate dissolution and feldspar hydrolysis, while the SAG are predominantly basic and sodium-bicarbonate type, probably related to carbonate precipitation and ionic exchange. The nitrate and chloride concentrations have been higher in the study central area and influenced by antropic factors. The concentrations of calcium, nitrate and chloride are higher and the pH is lower than in other samples collected in two wells from SAG. Such values are close to the ones got to SAB groundwater; what is suggestive of connection the two aquifers. Therefore, considering that in these wells the SAG thickness in the filter section is lower, it is likely that the two aquifers systems water mixing have been occurring inside of the well due to its construction / Mestre
6

Análise situacional qualitativa sobre as águas subterrâneas de Fortaleza, Ceará-Brasil como subsídio a gestão dos recursos hídricos / Analyze the qualitative groundwater in Fortaleza, Ceará - Brazil as a subsidy to Water Resources Management

Gomes, Maria da Conceição Rabelo January 2013 (has links)
GOMES, Maria da Conceição Rabelo. Análise situacional qualitativa sobre as águas subterrâneas de Fortaleza, Ceará-Brasil como subsídio a gestão dos recursos hídricos. 2013. 2014 f. Tese (Doutorado em geologia)- Universidade Federal do Ceará, Fortaleza-CE, 2013. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-07T19:13:27Z No. of bitstreams: 1 2013_tese_mcrgomes.pdf: 10273411 bytes, checksum: 48cc14c8d90946cb1168f02a2182583a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-06-07T23:25:26Z (GMT) No. of bitstreams: 1 2013_tese_mcrgomes.pdf: 10273411 bytes, checksum: 48cc14c8d90946cb1168f02a2182583a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-06-07T23:25:56Z (GMT) No. of bitstreams: 1 2013_tese_mcrgomes.pdf: 10273411 bytes, checksum: 48cc14c8d90946cb1168f02a2182583a (MD5) / Made available in DSpace on 2016-06-07T23:25:56Z (GMT). No. of bitstreams: 1 2013_tese_mcrgomes.pdf: 10273411 bytes, checksum: 48cc14c8d90946cb1168f02a2182583a (MD5) Previous issue date: 2013 / This work was conducted in the city of Fortaleza, located in the coastal zone of the northeastern portion of the state of Ceará, northeastern Brazil, covering 314,8 km² and 2.452,18 inhabitants, aimed to analyze the qualitative groundwater in Fortaleza, Ceará - Brazil as a subsidy to Water Resources Management. We collected 120 groundwater samples for physico-chemical analyzes, supplemented with 171 analyzes conducted between 2001-2009 (Data File Hydrogeology Laboratory / UFC). The data were processed with statistical analysis, correlation, identification of depositional environment, ionic relations, classification and framing of ionic water in Ordinance No. 2914/2011 of the Ministry of Health With these data it is concluded that the area is characterized by a reducing environment and acidic / basic with Eh in the range of -0,1 V to 0,2 V and pH between 4 and 9, the relationships ionic rMg+2/rCa+2 and rK+/rNa+, are associated with magnesia silicates and fixation K+ in clay, respectively. Chlorinated water predominate (86% and 81%) and Sodic (67% and 77%). Bacteriological analyzes of 87, 77% of these showed the presence of total coliform and / or fecal. The class of waters for irrigation is predominant C2 - S1 (49 and 73,5%), indicating salinity medium risk and low risk sodium, may be used largely for irrigation of soil and plants salt tolerance. The potential pollution sources identified in the area were building wells without taking up the technical standards of ABNT, cemeteries, inactive dumps, gas station, infiltration of contaminated surface water and lack of basic sanitation in neighborhoods of Fortaleza. Floods in Fortaleza result of the change of land use and occupation of fluvial and lacustrine environments, which coupled with the heaviest rains of the rainy season and concentrated, and not follow the growth of infrastructure and equipment drain at the same rate of growth of city, creates problems of this nature. For the formal insertion of the qualitative aspects of groundwater in vector management of water resources should be based on the fundamentals of Specific Legislation, Environmental Education Program, Watershed Characterization, Registration and diagnosis of wells and finally the management of water. / Esse trabalho foi realizado no município de Fortaleza, localizado na zona litorânea da porção nordeste do Estado do Ceará, Região Nordeste do Brasil, abrangendo 314,8 km² e com 2.452,18 habitantes, objetivando analisar a situação qualitativa das águas subterrâneas de Fortaleza, Ceará – Brasil como subsídio à Gestão dos Recursos Hídricos. Foram coletadas 120 amostras de água subterrânea para análises físico-químicas, complementadas com 171 análises realizadas entre 2001 a 2009 (Arquivo de dados do Laboratório de Hidrogeologia/UFC). Os dados foram tratados com análise estatística, correlação, identificação do ambiente de deposição, relações iônicas, classificação iônica e o enquadramento das águas na Portaria Nº 2914/2011 do Ministério da Saúde. Com estes dados conclui-se que área é caracterizada por um ambiente redutor e ácido/básico, com Eh no intervalo de -0,1 V e 0,2 V e de pH entre 4 e 9; as relações iônicas rMg+2/rCa+2 e rK+/rNa+, estão associadas à silicatos magnesianos e a fixação de K+ nos argilominerais, respectivamente. Predominam águas Cloretadas (86% e 81%) e Sódicas (67% e 77%). Das 87 análises bacteriológicas, 77% dessas mostraram a presença de coliformes totais e/ou fecais. A classe das águas para a irrigação que predomina é C2 - S1 (49 e 73,5%), indicando um médio risco de salinidade e baixo risco de sódio, podendo ser utilizadas para irrigação em grande parte dos solos e plantas com tolerância salina. As potenciais fontes de poluição identificadas na área foram a construção de poços tubulares sem adotar-se as normas técnicas da ABNT, cemitérios, lixões inativos, posto de combustíveis, infiltração de águas superficiais contaminadas e ausência de saneamento básico em bairros de Fortaleza. As inundações em Fortaleza resultam da alteração do uso do solo e ocupação dos ambientes fluviais e lacustres, que aliado às chuvas mais intensas e concentradas da quadra chuvosa, bem como ao não acompanhamento do crescimento de infraestruturas e equipamentos de drenagem no mesmo ritmo do crescimento da cidade, gera problemas desta natureza. Para a inserção formal dos aspectos qualitativos das águas subterrâneas no vetor gestão dos recursos hídricos, deve se ter como base os fundamentos de Legislação Específica, Programa de Educação Ambiental, Caracterização das Bacias Hidrográficas, Cadastramento e diagnóstico dos poços e por fim o gerenciamento das águas.
7

Caracterização hidrogeoquímica dos sistemas aquíferos Bauru e Guarani no município de Bauru

Silva, Sueli Roberta da [UNESP] 17 April 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-17Bitstream added on 2014-06-13T20:14:53Z : No. of bitstreams: 1 silva_sr_me_rcla.pdf: 2934840 bytes, checksum: 05006b853223794c37baaf547bce7974 (MD5) / Os Sistemas Aquíferos Bauru e Guarani, na área urbana do município de Bauru, apresentam-se em contato direto, diferentemente do que ocorre na maior parte da porção centro-oeste do estado de São Paulo, em que o Aquífero Serra Geral está entre eles. A partir da caracterização hidroquímica dos aquíferos, foi verificado que as águas do SAB são predominantemente ácidas e bicarbonatadas cálcicas, com provável dissolução de carbonatos e monossialitização de feldspatos, enquanto que as do SAG apresentam-se predominantemente básicas, bicarbonatadas sódicas, com provável precipitação de carbonatos e reações de troca catiônica. As concentrações de nitrato e cloreto apresentam-se maiores na porção central da área de estudo, e são características de influência antrópica. Em dois poços do SAG, as concentrações de cálcio, nitrato e cloreto são maiores e o valor de pH é menor que nas demais amostras deste aquífero; estes valores são similares aos obtidos para as águas do SAB; o que é sugestivo de conexão entre os dois aquíferos. No entanto, considerando que nestes poços a espessura do SAG na seção filtrante é menor, é provável que a mistura das águas dos dois sistemas aquíferos esteja ocorrendo dentro do próprio poço, devido suas características construtivas / The Guarani Aquifer System (SAG) and Bauru Aquifer System (SAB), in Bauru urban area, São Paulo state, are in direct contact, differently from what occurs in São Paulo state center-west, where the Serra Geral Aquifer is between them. The aquifer hydrogeochemistry characterization of the SAB had been shown that groundwater are predominantly acid and calcium-bicarbonate type, probable related to carbonate dissolution and feldspar hydrolysis, while the SAG are predominantly basic and sodium-bicarbonate type, probably related to carbonate precipitation and ionic exchange. The nitrate and chloride concentrations have been higher in the study central area and influenced by antropic factors. The concentrations of calcium, nitrate and chloride are higher and the pH is lower than in other samples collected in two wells from SAG. Such values are close to the ones got to SAB groundwater; what is suggestive of connection the two aquifers. Therefore, considering that in these wells the SAG thickness in the filter section is lower, it is likely that the two aquifers systems water mixing have been occurring inside of the well due to its construction
8

Estudo hidrogeoquímico da porção meridional do sistema aquífero Bauru no estado de São Paulo /

Barison, Marcelo Ribeiro. January 2003 (has links)
Orientador: Chang Hung Kiang / Banca: Osmar Sinelli / Banca: Ernani Francisco da Rosa Filho / Banca: Alexandre Campane Vidal / Banca: Gerson Cardoso da Silva Junior / Resumo: O Sistema Aqüífero Bauru é representado por sedimentos cretáceos do Grupo Bauru e constitui uma das principais fontes de exploração de água subterrânea do Estado de São Paulo. A área de estudo limita-se ao norte pelo rio Tietê, a oeste pelo rio Paraná, a sul pelo rio Paranapanema e a leste pelos litotipos da Formação Serra Geral. O presente trabalho tem como objetivo o estudo hidrogeoquímico das águas subterrâneas do Sistema Aqüífero Bauru utilizando-se conhecimentos de geoquímica de baixa temperatura e isotópica. Para a caracterização dos tipos de rochas existentes e sua evolução diagenética, foram realizadas análises petrográficas, de difratometria de Raios X e de Microscopia Eletrônica de Varredura (MEV Ambiental). A análise hidroquímica identificou a predominância de águas bicarbonatadas cálcicas e calco-magnesianas e secundariamente por águas bicarbonatadas sódicas. Algumas poucas foram classificadas como águas cloretadas. Os resultados isotópicos de 2H e de 18O mostram que as águas subterrâneas são de origem meteórica. A modelagem geoquímica foi executada com a utilização do programa SOLMINEQ88 pc/shell, versão 0.85, conforme proposto por PERKINS, GUNTER & NESBITT (1988) para a obtenção de cálculos de especiação das fases aquosas e do estado de saturação das fases minerais. No estudo da interação rocha-fluido, obteve-se que os arenitos que constituem o Grupo Bauru exerceram grande influência nos tipos hidroquímicos encontrados. Reações de substituição e de hidrólise de silicatos, dissolução de carbonatos e de outros minerais encontrados nos poros dos arenitos, como a analcima e a paligorskita, auxiliaram na incorporação de determinados tipos iônicos pelas águas do sistema aqüífero. / Abstract: The Bauru Aquifer System is represented by cretaceous sediments from Bauru Group and constitutes one of the main groundwater exploration sources from São Paulo State. The study area is limited to the north by Tietê river, to the west by Paraná river, to the south by Parapanema river and to the east by rocks of Serra Geral Formation. The present research aims to study the hydrogeochemistry behaviour of groundwaters from Bauru Aquifer System using the knowledge of isotopic and low temperature geochemistry. To the characterization of rocks and their diagenetic evolution, petrographic, X-ray difractometry and scan electronic microscope (SEM) analysis have been executed. To hydrochemical analysis revealed mainly calcium bicarbonate and calcium-magnesium bicarbonate waters composition in the study area. Other water samples are sodium bicarbonate and a few ones are chlorinated waters. The isotopic results of 2H and 18O revealed meteoric origin for the groundwaters. The geochemistry modeling was executed using the SOLMINEQ88 pc shell program, version 0.85 (PERKINS, GUNTER & NESBITT, 1988) to obtain the speciation calculus of aqueous phases and the saturation state of mineral phases. The rock-fluid interaction study showed that the sandstones from Bauru Group influenced in the hydrochemistry types found. Silicate dissolution and hydrolysis reactions, carbonate dissolution and the filling of other minerals in the sandstones pores (analcima and palygorkskite), are responsible for the incorporation of determinate ionic concentrations by the waters from aquifer system. / Doutor
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Using hydrogeochemistry and geophysical techniques to determine the extent of connectivity between Langerban road and Elandsfontein aquifer system, West Coast, South Africa

Van Der Schyff, Malikah January 2020 (has links)
Magister Scientiae (Integrated Water Resource Management) / The heterogeneity in groundwater systems suggest that not all aquifers are connected in groundwater systems. This study is about the interaction between aquifers within groundwater system. Langebaan Road and Elandsfontein aquifers in the West Coast groundwater aquifer system were chosen as case studies. These units were chosen because the previous studies on groundwater excluded the aspect of connectivity between aquifers from methods perspective which is the focus on the current study. The second reason for the study area was the present of human activities and ecosystems which are proved to be groundwater dependents. Aquifer-aquifer interaction refers to hydraulic connection between two aquifers. The interaction is influenced by hydraulic pressure and lithology of geological strata, their integrity and spatial continuity. While factors for such connectivity are well known, appropriate techniques to establish the extent of connectivity remain poorly understood and hence the need to employ various techniques so that the extent of connectivity between the two aquifers is established. Understanding the connectivity between aquifers is important because such connectivity explains the pathways for the availability of groundwater in each aquifer unit and the associated groundwater quality in each unit that supports human activities and sustain ecological systems.
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Flux and Source of Dissolved Organic and Inorganic Constituents in Managed Headwaters of the Upper Gulf Coastal Plain, Mississippi

Mangum, Clay Nicholas 15 December 2012 (has links)
Headwater watersheds initiate material export to downstream environments. A nested headwater study examined the flux and source of dissolved constituents and water from a perennial stream and four ephemeral/intermittent streams in the Upper Gulf Coastal Plain, Mississippi. Water was collected during storm and baseflow conditions. Multiple linear regression was used to model constituent concentration and calculate flux. Source of water was determined using principle components analysis and end-member mixing analysis. Rain was the major source of water discharged from the ephemeral and intermittent streams, while groundwater was the major source for water discharged by the perennial stream during events. Baseflow from both stream types was dominated by groundwater sources. The perennial stream had an area weighted average yields of 10.1, 0.01, 1.0, 0.6, and 0.03 kg-1 ha-1 yr-1 of DON, NO3--N, NH4+-N, PO4-3, and DOC,respectively. This research highlights the interaction of source water and dissolved constituent flux.

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