Hidrogeologia dos sistemas aquíferos do Sinclinal Dom Bosco, Quadrilátero Ferrífero - Brasil

Abstract

The Iron Quadrangle (Minas Gerais, Brazil) is a province of high historical and geological significance, shaped by gold and iron mining and by its hydrological importance in supplying the Belo Horizonte Metropolitan Region. Within this context, the Dom Bosco Syncline, located in the southwestern Iron Quadrangle, remains relatively undercharacterized from a hydrogeological standpoint despite directly supplying historic centers such as Ouro Preto and Mariana. This dissertation presents a hydrogeological characterization of the Dom Bosco Syncline by combining a hydraulic assessment, a GIS-based spatially distributed water balance, and integration into a three-dimensional aquifer-system model, with the purpose of providing a consistent picture of groundwater availability and dynamics to support management. The approach involved a critical compilation of well and test data, interpretation of pumping tests to estimate parameters and define hydrostratigraphic units, construction of the potentiometric surface and three-dimensional rendering, and water-balance closure using geographic information systems by interpolating precipitation, actual evapotranspiration, and recharge- modulating factors. Potential recharge aggregated by hydrostratigraphic unit confirms the prominence of the Cauê Aquifer (≈33.5%) and the complementary roles of the Gandarela (≈25.7%) and Moeda (≈23.0%) aquifers, with Itacolomi (≈13.5%) and Sabará/Piracicaba (≈12.2%) at lower levels, establishing a hierarchy that guides allocation decisions and the protection of zones with higher recharge indices. In the hydraulic assessment, the Cauê Aquifer exhibits transmissivity on the order of 10⁻³ m² s⁻¹ in representative wells from the central portion of the syncline, which explains its operational appeal while underscoring the need to monitor localized pumping stresses concentrated in this unit. The integration of cartographic products and parameters into a three-dimensional aquifer-system model relates the structural framework to flow tendencies and to recharge and discharge domains, consolidating a coherent representation of the study area.