Figure 2: Stratigraphic columns and correlation section (see trace in Figure 1) compared with the WNW, SSE cross section by Buonasorte et al. [24]. RAI01, Alfina004, and Alfina014 wells belong to the first drilling campaign (1971-1972), while the deepest Alfina015 well was drilled on 1987-1988. The Castel Giorgio-Torre Alfina geothermal reservoir is hosted in a structural high (i.e., horst structure) of fractured Mesozoic limestones belonging to Tuscan and Umbria Nappe complex (light and dark blue units).