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Submitted by Ismael Souza (ismael.souza@ufba.br) on 2022-02-10T17:25:59Z No. of bitstreams: 1 Dissertacao_Josimar_Andre (2).pdf: 2018606 bytes, checksum: 750c67ac95719a603980df425d799022 (MD5) Approved for entry into archive by Solange Rocha (soluny@gmail.com) on 2022-02-10T19:03:51Z (GMT) No. of bitstreams: 1 Dissertacao_Josimar_Andre (2).pdf: 2018606 bytes, checksum: 750c67ac95719a603980df425d799022 (MD5) Made available in DSpace on 2022-02-10T19:03:51Z (GMT). No. of bitstreams: 1 Dissertacao_Josimar_Andre (2).pdf: 2018606 bytes, checksum: 750c67ac95719a603980df425d799022 (MD5) Previous issue date: 2021-09-24 CAPES Investigações hidrogeoquímicas foram realizadas para identificar os processos que afetam a química das águas subterrâneas na região que compreende a folha de Amargosa. Esta área localiza-se na porção Centro-sul da Bahia, é delimitada pelos paralelos 13°00’S e 13°30’S e os meridianos 39° 30’W e 40º00' W, e possui uma área de aproximadamente 2.996 km². As unidades geológicas que a compõem, integram o contexto tectônico do Bloco Jequié, umas das entidades geotectônicas arqueanas pertencentes ao Cráton do São Francisco, estruturado após a colisão paleoproterozóica. Para alcançar os objetivos, análises físico-químicas de 49 poços representativos foram utilizadas e interpretadas segundo a química dos íons principais, gráficos convencionais e bivariados. A ampla variação de fácies hidroquímicas demonstra a heterogeneidade do meio aquífero, predominando fácies HCO3- nas regiões de clima subúmido e fluxo ativo enquanto as fácies Cl ocorrem em condições semiáridas e fluxo lento. Os mecanismos de interação água-rocha e evaporação controlam a química das águas subterrâneas com destaque para os processos geoquímicos de intemperismo dos silicatos (plagioclásios, piroxênios e biotita); desequilíbrio cloro-alcalino, comuns nas fácies HCO3- e reação de troca de base, representativos das fácies Cl. Os resultados dessa pesquisa permitiram elevar o conhecimento de um sistema complexo e lançar as bases para uma exploração mais racional de aquíferos anisotrópicos. Hydrogeochemical investigations were carried out to identify the processes that affect the chemistry of groundwater in the region that comprises the Amargosa sheet. This area is located in the Center-South portion of Bahia, is delimited by the parallels 13°00'S and 13°30'S and the meridians 39°30'W and 40°00'W, and has an area of approximately 2,996 km². The geological units that compose it are part of the tectonic context of the Jequié Block, one of the Archean geotectonic entities appurtenant to the São Francisco Craton, structured after the Paleoproterozoic collision. To reach the objectives, physicochemical analyses of 49 representative wells were used and interpreted according to the main ion chemistry, conventional and bivariate graphs. The wide range of hydrochemical facies demonstrates the heterogeneity of the aquifer environment, with HCO3- facies predominating in regions of sub-humid climate and active flow, while Cl facies occur in semi-arid and slow flow conditions. The mechanisms of water-rock interaction and evaporation control the groundwater chemistry, highlighting the geochemical weathering processes of silicates (plagioclases, pyroxenes and biotite); chlorine-alkaline imbalance, common in the HCO3- facies and base exchange reaction, representative of the Cl facies. The results of this research made it possible to increase the knowledge of a complex system and establish the basis for a more rational exploration of anisotropic aquifers.

Made available in DSpace on 2020-12-12T02:10:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Groundwater extracted from crystalline aquifers is the main water supply in many parts of the world, particularly in developing regions such as Sub-Saharan Africa, Brazil and India. Decades of research have revealed the strong complexity of the flow regime in these aquifers, which are notably heterogeneous and anisotropic. It has been long assumed in Brazil that water is stored in vertical geological discontinuities associated with ancient fault zones. Given the high potential of pumping tests to identify flow regimes, this paper presents a derivative analysis of pumping tests performed in three wells located in the Jundiaí municipality - State of São Paulo, Brazil, aiming to improve the understanding of conceptual flow modeling of fractured aquifers. Adjustment attempts applying solutions for simple vertical and horizontal fractures did not produce satisfactory results. Although no tested solution produced perfect adjustments to the drawdown curves obtained in the pumping tests, the best adjustments were observed when the solution for fractured aquifer with double porosity was applied, which is compatible with the geological context of study area. Further studies, similar to those described in this paper, should be conducted to improve the understanding of flow conditioners for this type of aquifer. FRC Serviços Geológicos e Ambientais Ltda, Rua Congo, 313, Torre 2, Apt. 106, Bairro Jardim Bonfiglioli, 313, Jardim Bonfiglioli Laboratório de Estudos de Bacias - UNESP Centro de Estudos Ambientais - UNESP Campus de Rio Claro, Av. 24-A, 1515, Bairro Bela Vista Laboratório de Estudos de Bacias - UNESP Campus de Rio Claro, Av. 24-A, 1515, Bairro Bela Vista Laboratório de Estudos de Bacias - UNESP Centro de Estudos Ambientais - UNESP Departamento de Geologia Aplicada Instituto de Geociências e Ciências Exatas - UNESP Campus de Rio Claro, Av. 24-A, 1515, Bairro Bela Vista Laboratório de Estudos de Bacias - UNESP Centro de Estudos Ambientais - UNESP Campus de Rio Claro, Av. 24-A, 1515, Bairro Bela Vista Laboratório de Estudos de Bacias - UNESP Campus de Rio Claro, Av. 24-A, 1515, Bairro Bela Vista Laboratório de Estudos de Bacias - UNESP Centro de Estudos Ambientais - UNESP Departamento de Geologia Aplicada Instituto de Geociências e Ciências Exatas - UNESP Campus de Rio Claro, Av. 24-A, 1515, Bairro Bela Vista

Made available in DSpace on 2020-12-12T01:46:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 The mechanisms related to rock-water interaction are important to understand the quality of groundwater. The chemical composition of 38 brands of bottled water from crystalline aquifers located in the South and Southeast regions of Brazil was determined for understanding the rock-water interaction processes. The results indicate that the water samples show different stages of rock-water interaction, which can be measured by the concentration of HCO3- ion. The exploratory analysis indicates that low mineralized water, probably from recent recharge, is of mixed type. On the other hand, more mineralized water is of bicarbonate type, ranging from sodium to calcium, and with a high proportion of magnesium. Despite the different compositions of the rocks that make up the studied aquifers, calcium-magnesium silicates, predominantly represented by hornblende, are the ones that mainly affect the water composition. Sodium and part of the calcium in water are derived from the hydrolysis of plagioclase, whereas potassium is derived from the dissolution of potassium feldspar. Laboratório de Estudos de Bacias UNESP Centro de Estudos Ambientais Departamento de Geologia Aplicada Instituto de Geociências e Ciências Exatas Campus de Rio Claro, Av. 24A, 1515, Bairro Bela Vista Laboratório de Estudos de Bacias UNESP Centro de Estudos Ambientais Departamento de Geologia Aplicada Instituto de Geociências e Ciências Exatas Campus de Rio Claro, Av. 24A, 1515, Bairro Bela Vista