Assessing mantle versus crustal sources for non-volcanic degassing along fault zones in the actively extending southern Apennines mountain belt (Italy)
The actively extending axial zone of the southern Apennine mountain belt of Italy is characterized by a substantial flow of non-volcanic gas to the surface. In this study, we have analyzed the correlation between the active tectonic framework of the Matese Ridge area and the high gas emissions found to the southwest, which includes large amounts of CO2 (up to 99 vol%), CH4 (up to 0.55 vol%), and He (up to 52 ppmv). We measured CO2 and CH4 fluxes of up to 34000 g d−1 and 2000 g d−1, respectively, from zones of focused degassing (gas vents and associated strong diffuse emission).