Structural, hydrogeological and hydrochemical characterization of aquifers in the Paraná Basin: An integrated literature review

The Paraná Basin in Brazil is of vital importance and because of a large groundwater reservoir and the high exploitation of this resource by the population a structural and hydrogeochemical knowledge is needed. Objectives: 1) Analyze studies that address the structural, hydrogeological and hydrochemical characterization of aquifers in the Paraná Basin; 2) Highlight the main techniques used in the respective studies and the scientific development arising from the use of these techniques for a better hydrochemical and structural understanding of the Paraná Basin. Methodology: Tracing lineaments from satellite image and field work are the main techniques used for structural characterization. For hydrochemical analyses, factorial methods physical-chemical analyses are used. Results: the most common chemical types of groundwater that circulate in the sedimentary and volcanic units of the Paraná Basin, which include the Pirambóia, Irati, Rio Bonito, Botucatu and Serra Geral formations are calciumbicarbonates, calcium-magnesian bicarbonates, calcium-sodium bicarbonates and sodium-sulphate-chloride bicarbonates. Sodium-sulfated waters are not found in the Serra Geral Formation, except when they come from the sedimentary units. Sodium and sulfate are not expected ions in basalt weathering, and therefore a greater understanding is needed on structural communication by means of faults that occur between the Serra Geral Aquifer System (SGAS) and the mesozoic and permian sedimentary aquifers and aquitards that contribute for unexpected ions in the SGAS. Conclusion: The Paraná Basin is a reason for interest in geological studies in Brazil because of its link to several areas of interest in geosciences, which include hydrochemistry, stratigraphy, paleontology and hydrogeology.