Influence of hydrothermal fluids enriched in As and F on the chemistry of groundwaters of the Duero Basin, Spain

Chemical and isotopic data of groundwaters from the south edge of the Duero Basin have been interpreted by multivariate statistical analysis including HCA and PCA. The results suggest that waters enriched in arsenic, fluoride and other associated trace elements are alkaline Na-HCO₃ cold-hydrothermal waters, flowing through main faults of the basement.