Geochemical Evolution in Historical Time of Thermal Mineral Springs at Campetti Southwest (Veii, Central Italy) through Geoarcheological Investigation

A multidisciplinary study, involving hydrogeological, geochemical, and mineralogical analyses, was conducted to define the evolution of thermal mineral springs in the Sabatini Volcanic District (SVD) (Central Italy) in a historic period. The outcomes were integrated with the archeological findings to improve the knowledge of the evolution of Veii, a settlement established since the Iron Age and later expanded by Etruscans and Romans. During the archeological excavations, water-related buildings were identified, especially at the Campetti Southwest site in the Veii settlement. Votive inscriptions also suggest the presence of buildings linked to sacred waters, even if a clear definition of the source and type of water is missing. In the SVD, some low-flow thermal mineral springs are present as a result of the mixing of thermal and CO2-rich groundwater from the deep carbonate aquifer and the cold, shallow volcanic aquifer. Mineralogical and chemical analyses characterized the travertine and Fe-hydroxide deposits on Roman tanks and walls in Campetti Southwest and in a nearby ancient Roman bath along the Valchetta River. These deposits showed different relative concentrations of sedimentary and volcanic-related elements, testifying a geochemical evolution of the groundwater mixing and the presence of a paleothermal mineral spring in Campetti Southwest.