Dataset of the soil CO2 degassing measurements and carbon isotopic composition of the interstitial gas in the Larderello geothermal system area, Italy

This dataset presents the identification number, geographic coordinates, soil temperature, CO2 flux and δ13C-CO2 values of the interstitial gas for each sampling site related to hot and cold degassing areas of the Larderello geothermal field (Tuscany, Italy). A total amount of 648 flux measurements were carried out in nine different degassing areas. In specific degassing sites, 77 interstitial gas samples, for the determination of the δ13C-CO2 values, were also collected. The flux measurements and isotopic composition of C are used to compute a first quantification of the diffuse CO2 flux emitted from the Larderello geothermal field by incorporating measurements from both thermally active and cold degassing soils located near the core and at the periphery of the system, respectively, and to bring further elements for defining the role of the transfer zones in controlling the geothermal fluid pathways. Moreover, CO2 fluxes and C isotopic composition of the interstitial soil CO2 were used to identify the origin of the CO2 and its link with the geothermal reservoir(s).