Water-rock interactions in a site investigated for geochemical precursors of earthquakes: the Pieve Fosciana spring (Italy)

The Serchio Valley is one of the regions of highest seismic risk in Tuscany, Italy. As a part of a seismic prevention/prediction pilot project funded by Regional Government of Tuscany, the Pieve Fosciana spring, a perennial thermo-mineral spring emerging in correspondence with some of the most important neo-tectonic structures of the Serchio Valley, was monitored for possible geochemical precursors of earthquakes. The investigation protocol considered the coupled use of chemical analyses on water aliquots sampled during discrete surveys, and of continuous signals for selected physical-chemical parameters acquired via an automatic station equipped with a suite of parameter-specific sensors. By combining these data, the geochemical background of the system was defined, and an integrated hydrogeological and geochemical model of the hydrothermal aquifer feeding the spring was elaborated.