Use of the Hydrochemical Facies Diagram (HFE-D) for the evaluation of salinization by seawater intrusion in the coastal Oropesa Plain: Comparative analysis with the coastal Vinaroz Plain, Spain

Abstract

The present analysis aims to recognize and understand the temporal and spatial evolution of seawater intrusion into the Oropesa detrital aquifer on Spain's eastern coast through the early 1990s. In this coastal aquifer, groundwater salinization has extended over the entire Oropesa Plain; it is mainly controlled by direct and reverse ion exchange reactions related to intrusion and freshening phases, respectively, which alternate over time. Hydrochemical facies analysis, using the HFE-Diagram, was applied to understand the spatiotemporal dynamics of the seawater intrusion process. The analysis also considered the neighboring Vinaroz Plain, located to the north. Although the two alluvial plains were studied over the same time periods, the HFE-Diagram analysis of the hydrochemical facies highlighted differences in the behavior of each coastal aquifer with respect to salinization by seawater intrusion.