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 amountof 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 ofthe impervious flysch cover and the top of the geothermal reservoir hosted in fractured Mesozoic lime-stones were reconstructed by a 3D-GIS modelling. Our results are consistent with a geothermal reservoir(T ~140oC) at ~1000 m depth, with an estimated thermal energy capacity of 46-48 MWt.