EM - Escola de Minas

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6

Notícias

A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.

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Resultados da Pesquisa

Agora exibindo 1 - 3 de 3
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    Determining groundwater availability and aquifer recharge using GIS in a highly urbanized watershed.
    (2021) Conicelli, Bruno Pirilo; Hirata, Ricardo; Galvão, Paulo Henrique Ferreira; Luiz, Mariana Bernardino; Simonato, Mateus Delatim; Abreu, Marcio Costa; Aranda, Nataly; Terada, Rafael
    Extensive urbanized areas, characterized by waterproofed soils, increase runoff, which reduces the rainwater infiltration into the ground. However, water, sewer, and rainwater distribution systems leak, as there is excess irrigation in green areas, resulting in anthropic recharging in urban aquifers larger than in rural areas with equivalent climates. This scenario occurs in the Upper Tietˆe Watershed (UTW), an area of 5,868 km2 that drains the principal rivers of the Sao ̃ Paulo’s metropolitan region in Brazil, where groundwater plays a complementary role for domestic, industrial, and agricultural supplies, totalizing extraction rates higher than 11 m3 /s. In this paper, a Geographical Information System (GIS) was established to assess regional groundwater availabilities using adaptations of classic recharge methods such as soil water budget calculations and estimation of minimum sustainable river flow. For this, a surface runoff map, based on soil and slope terrain data, was evaluated using the information on water and sanitation infrastructure and meteorological data. We found that recharge in urban areas (with water and sewer mains) was 437 mm/yr and 106–407 mm/yr in rural areas. Considering the need to maintain a minimum historical flow of 20 m3 /s in the hydrographic basin of the Tietˆe River, the total exploitable groundwater is 33 m3 /s. The compilation of various GIS methods can help decision-makers develop alternative water security management plans in complex urbanized-regions such as in the metropolis of Sao ̃ Paulo.
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    Recharge sources and hydraulic communication of karst aquifer, São Miguel watershed, MG, Brazil.
    (2020) Lucon, Thiago Nogueira; Costa, Adivane Terezinha; Galvão, Paulo Henrique Ferreira; Leite, Mariangela Garcia Praça; Madeira, Thiago José Augusto; Nogueira, Leonardo Brandão
    The main public water supply in the São Miguel watershed (MG, Brazil) comes from a well-developed karst region, where information about hydraulic communications between caves entrances, sinkholes, recharge and discharge areas are still unknown. The study aims to identify regional hydrogeological processes describing groundwater hydrochemical evolution, interactions between meteoric, surface and ground waters, recharge and discharge sources, and possible hydraulic communications for proper management of water resources. Geophysical data were analyzed and water samples (meteoric, surface, and groundwater) throughout the watershed were collected for stable isotopes (18O and 2 H) and major ions analyzes. Results indicated strong influences of regional geological structures in the karst water flow directions; high concentrations of major ions in the central region of the watershed are common; karstification processes and aquifer recharge are more active during the rainy season, while in the dry season the watershed is supplied by groundwater.
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    Transmissivity of aquifer by capture zone method : an application in the Sete Lagoas Karst aquifer, MG, Brazil.
    (2017) Galvão, Paulo Henrique Ferreira; Halihan, Todd; Hirata, Ricardo
    Transmissivity is an important hydraulic parameter to determine the amount of water passed horizontally across a given saturated thickness of an aquifer. The techniques to quantify this parameter, such as grain size analyses or pumping tests, can have limitations of time/spatial scale, viability, or economically. One technique that can be used, but little adopted, is the capture zone analysis. In this paper, capture zone analytical equations were used to estimate transmissivity values in order to verify the effectiveness of this methodology as alternative in situations where other traditional methods present implementation difficulties. The results were compared with field data estimated by aquifer tests conducted in the same region. A sensitivity analysis was also performed to identify possible discrepancies between the analytical and field data results. The aquifer studied was the Sete Lagoas Karst Aquifer in the urban region of the municipality of Sete Lagoas, Brazil. The method proved to be a viable and economical tool, where the analytical values compared to the aquifer tests showed similarities, being confirmed by a sensitivity analysis. However, a reliable potentiometric surface map, which enables the identification of the parameters for analytical capture zone equations, is needed.