Estimando a Potencialidade Hidrogeológica da Bacia Cárstica do Rio Vieira, Região Hidrográfica do Verde Grande, MG

Abstract

In the Vieira River basin, north of Minas Gerais, where there is a predominance of three hydrogeological domains (granular, fractured, and karst-fractured), issues about inefficiency in the water resource management, coupled with the semi-arid climate and scarcity of local studies, worsen the conditions of water availability, mainly in the dry season. The objective of this paper was to apply and adapt a method of delimitation of hydrogeological potentiality in a karst region by associating geological and morphological data well pumping tests (specific capacity, Q/s, and transmissivity, T), as well as geophysics, and remote sensing. The method was validated by calibrating weights of thematic maps with values of T and Q/s, indicating that the potentially more productive regions are correlated to four factors: 1) density of lineaments (morphostructural and geophysical) and karst features, mainly in the NE-SW and NNE-SSW directions; 2) types of local aquifer systems; 3) low slopes and nearby drainages; and 4) recharge. In the whole area, the spatial distribution of wells with high productivity variability is remarkable (Q/s ranging from 0.01 to 60 m³/h/m and T ranging from 10-5 to 10-3 m2/h), which indicates how much the karst aquifer in the region is anisotropic and heterogeneous.