Geofísica aplicada à segurança de barragens de rejeitos de mineração : aplicação da tomografia elétrica de resistividade a um estudo de caso na Baixada Cuiabana no estado de Mato Grosso

Abstract

Dams are structures built to create a reservoir for storing fluid or high water content materials. This type of structure is used for the most diverse purposes, among which the accumulation of water for desedentation, power generation or even the disposition of mining tailings stands out. These structures can be built with the use of various techniques and materials. Mining industry usually use earth dams. However, these dams have problems that, in some cases, can only be detected and monitored properly with instrumentation or geophysical research methods. Thus, the present work aims to apply the geophysical method of electroresistivity for the analysis and understanding of water percolation in the body of a dam located on the boundary between the municipalities of Poconé and Nossa Senhora do Livramento, State of Mato Grosso, as well as the relationship of this phenomenon with security of this type of structure. The profile lines to perform the tests were built on the crest, berm and the base of two sectors of the dam, and the electrical walking technique with a dipole-dipole arrangement was applied. As a result, in addition to demonstrating the viability of employment of this method for dams constructed in a similar way to the selected, places were identified for improvement in geotechnical investigation and monitoring plan, considering the resistivity anomalies detected.