Hydrochemical compartment, hydraulic connectivity, and hydrogeochemical characterization of serra geral aquifer system

The Serra Geral Aquifer System (SGAS) has great potential for exploring its waters. However, high salinity values are found in certain regions. This higher than expected salinity is due to the connection between hydroestratigraphic units under the SGAS, such as the Guarani aquifer system (GAS) and Permian aquitards and aquifers, such as Irati and Rio Bonito. The principal components analyses included the K-means method and dendrogram analyzed together with a map of structural faults and simulation which resulted in the analysis of preferential directions for the flow of groundwater and which are the main faults that contribute to the decrease in potentiometry in the SGAS, which allow ions such as sodium and sulfate to rise to the SGAS from GAS and pre-GAS sedimentary units. The simulation helped to indicate the areas with the highest salinity and which coincided with the major regional faults. The study area was divided into five zones, based on large regional faults. The objective is to characterize which regional faults are important for communication between these aquifers systems and to identify the areas where the highest salinities occur, which are directly correlated with the potentiometry of SGAS and GAS that must match for high salinity values to occur. This communication is very evident through simulation techniques and the study of SGAS and GAS potenctiometric isohypses. The analysis of the fracturing degree of minor faults associated with major faults also determines the places where the rise of saline waters is possible, because these major faults lower the potentiometric levels of GAS.