Diagnóstico hidrogeológico-geotécnico por meio de análise estrutural na Mina Osamu Utsumi (Poços de Caldas - MG)

• Autor(a) principal: Targa, Débora Andrade [UNESP]
• Data de Publicação: 2018
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/203228; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2018-12-11/000909718.pdf
• topic: Águas subterrâneas; Hidrogeologia; Geologia estrutural; Mineralogia; Mineração a céu aberto; Geomorfologia; Deslizamentos (Geologia); Poços de Caldas (MG)

The Osamu Utsumi Mine is located in the Poços de Caldas alkaline massif, in southwest region of Minas Gerais State. The mine goes through serious environmental issues due to the substantial volume of water provided by the pit area that need chemical treatment because of the presence of heavy metals and radioactive element. This work aims to understand the underground waterflows that flow through the discontinuities along the rock masses and supply water to the pit area. Thus, by a structural analysis of the main fractures systems of the four mining fronts, this work brings a hidrogeological-geotechnical diagnosis of the pit area. A total of 755 fractures planes were measured and organized on the Openstereo Software, which showed two main systems of fractures. The main one has strike to NE-SW and, subordinately, to NW-SE, whose dip direction is to NW and coincides to the regional drainage system direction. As the mining fronts have been analysed individually, it was noticed that, in all of them, the dip direction of fractures planes is projected into the center of the pit, working as a water basin collector. The presence of water is mainly observed in the fronts SE, SW and NW, illustrated by white stains of kaolinite and active water flows, like little streams. The fractures systems intersect each other and form gutters that canalize the waterflow toward the pit. It is suggested the rock masses and the fractures pattern set a fracture aquifer system. The fracture patterns also showed that the mining fronts SE and SW have a pre-arrangement to the occurrence of planar and wedge landslides, whose slope dynamics processes were recorded on the slopes and prevent access to some of the mine's benches, as well as representing a risk to the proper functioning of the mine. The front NW also showed some blocks and boulders along the slope base as a result of fall process. The relation between the plane of the slope face and the intersection line of...