Estimation of the geothermal potential of the Caldara di Manziana site in the Sabatini Volcanic District (central Italy) by integrating geochemical data and 3D-GIS modelling

This study evaluated the geothermal potential of Caldara di Manziana in central Italy. The chemical composition of gas emissions was used for geothermometric-geobarometric estimations and the total amount of CO2 released was assessed. The subsurface geology was reconstructed using data from deep exploratory and shallow temperature-gradient wells. The bottom of the superficial volcanic deposits, the thickness of the impervious flysch cover and the top of the geothermal reservoir hosted in fractured Mesozoic limestones were reconstructed by a 3D-GIS modelling. Our results are consistent with a geothermal reservoir (T ~140 °C) at ~1000 m depth, with an estimated thermal energy capacity of 46-48 MWt.