Multidisciplinary Approach to the Study of the Relationships Between Shallow and Deep Circulation of Geofluids

Abstract

We present a multidisciplinary integrated study performed to get insights into circulation pattern of geothermal fluids uprising in the Equi Terme area (Alpi Apuane, Tuscany). Geological-structural surveys were carried out to define the structural setting of the area and to characterize geometries and kinematics of fault-fracture systems. Chemical and isotopic analyses were carried out on thermal water and cold springs. Samples were repeatedly collected in the different seasons, measuring temperature, electrical conductivity, pH and total alkalinity. Furthermore, a geophysical survey has been carried out in order to get insights into the resistivity distribution at depth. The geophysical approach used MagnetoTelluric (MT) and Electrical Resistivity Tomography (ERT). This multidisciplinary approach proved to be a powerful tool, since it unravels the high complexity of this natural geothermal system and provides useful hints in order to reconstruct the complex fluid circulation pattern feeding the Equi Terme thermal spring.