RESEARCH ARTICLE Volatiles and energy released by Puracé volcano Luisa Fernanda Meza Maldonado 1,2 & Salvatore Inguaggiato 3 & Marco Tulio Jaramillo 2 & Gustavo Garzón Valencia 4 & Agnes Mazot 5 Received: 23 March 2017 /Accepted: 28 October 2017 /Published online: 14 November 2017 # Springer-Verlag GmbH Germany 2017 Abstract Total CO 2 output of Puracé volcano (Colombia) was estimated on the basis of fluids discharged by fumaroles, soil gases, and dissolved carbon species in the aquifer. The soil CO 2 emission was computed from a field survey of 512 points of CO 2 soil flux measurements at the main degassing areas of Puracé volcano. The CO 2 flux from Puracé’ s plume was estimated using an indirect method, that used the SO 2 plume flux and CO 2 /SO 2 ratio of the main high temperature fumarole. The total output of CO 2 was estimated at ≅ 1500 t/ day. The main contribution of CO 2 comes from the plume (summit degassing) and from soil degassing that emit 673 and 812 t/day, respectively. The contributions of summit and soil degassing areas are comparable, indicating an intermedi- ate degassing style partitioned between closed and open con- duit systems. The estimated water vapor discharge (as derived from the chemical composition of the fumaroles, the H 2 O/ CO 2 ratio, and the SO 2 plume flux) allowed calculation of the total thermal energy (fumarolic, soil degassing, and aqui- fer) released from the Puracé volcanic system. This was 360 MW. Keywords CO 2 output . Helium isotope . Puracé volcano . Soil CO 2 degassing . SO 2 plume output Introduction Actively degassing systems are well known as being s/ ources of open-vent plumes and fumarole fields that dis- charge significant amounts of gas into the atmosphere (Brantley and Koepenick 1995; Arthur 2000; Mörner and Etiope 2002). Moreover, several investigations car- ried out over the last three decades have shown the im- portance of volcanic gas emissions from soils and aqui- fers (e.g., Inguaggiato et al. 2012a, b, 2013; Cardellini et al. 2003; Chiodini et al., 1996; Pecoraino et al. 2005; Mazot et al. 2011). Soil degassing in volcanic areas is characterized mainly by CO 2 emissions, because CO 2 represents the dominant dry volcanic gas species. The study of the fluxes of CO 2 emitted from active degassing systems has significant environmental and surveillance applications (Baubron et al. 1991; Carapezza et al. 2004; Brusca et al. 2004; Inguaggiato et al. 2011 , 2017a). The measurement of CO 2 fluxes from soils is a tool that can be used to quantify changes in surface geother- mal activity (Chiodini et al. 2005; Inguaggiato et al. 2012a, b, 2017a, b; Fridriksson 2009). In such cases, the flux of CO 2 is effectively used as a tracer for magma outgassing due to its low solubility in silicate melts (Gutiérrez 2009). This gas travels to the surface through advective-diffusive processes and manifests itself at the surface of the volcano through degassing (Hernández et al. 2001). The study of CO 2 emitted by different hy- drothermal emission styles (fumaroles, soil degassing, geysers, mud pools) provides crucial information for Editorial responsibility: T.P. Fischer * Salvatore Inguaggiato salvatore.inguaggiato@ingv.it 1 Servicio Geológico Colombiano, Observatorio Vulcanológico y Sismológico de Popayán, Popayán, Colombia 2 Universidad de Caldas, Manizales, Colombia 3 Istituto Nazionale di Geofisica e Vulcanologia, Palermo, Italy 4 Servicio Geológico Colombiano, Calì, Colombia 5 GNS Science Wairakei Research Centre, Taupo, New Zealand Bull Volcanol (2017) 79: 84 https://doi.org/10.1007/s00445-017-1168-y