Spatial domain analysis of carbon dioxide from soils on Vulcano Island: Implications for CO2 output evaluation

Carbon isotopic signature of interstitial soil gases reveals the potential role of ecosystems in mitigating geogenic greenhouse gas emissions: Case studies from hydrothermal systems in Italy

“…Conversely, diffusion through the soil is able to induce a fractionation effect due to the faster kinetics of 12 CO 2 escaping towards the atmosphere, producing an increase of δ 13 C-CO 2 values within the shallow CO 2 -depleted soil layers (e.g. Cerling and Quade, 1993;Capasso et al, 1997Capasso et al, , 2001bDi Martino et al, 2016;Etiope et al, 2009 and references therein;Federico et al, 2010;Kayler et al, 2010). Nevertheless, even though it was not possible to develop a diffusion-enrichment model to be compared with field data due to the lack of δ 13 C-CO 2 measurements systematically performed along vertical profiles within the soil, the hypothesis of a 13 C enrichment induced by gas diffusion does not agree with the high ΦCO 2 values (up to 972 g m −2 day −1 ) and CO 2 contents (N800 mmol/mol) characterizing soil gases, whose δ 13 C-CO 2 values were up to 3‰ higher than those measured in fumarolic discharges.…”

Structural architecture releasing deep-sourced carbon dioxide diffuse degassing at the Caviahue – Copahue Volcanic Complex

“…Date Thermal site (i) gas diffusion through the soil (e.g. Cerling and Quade, 1993;Capasso et al, 1997Capasso et al, , 2001Di Martino et al, 2016;Etiope et al, 2009 and references therein;Federico et al, 2010;Kayler et al, 2010) and (ii) microbial CO 2 uptake processes (Tassi et al, 2015 and references therein; e.g. Freude and Blaser, 2016 and references therein) are able to produce an isotope fractionation effect resulting in an enrichment in 13 C in residual CO 2 .…”

A multi-instrumental geochemical approach to assess the environmental impact of CO2-rich gas emissions in a densely populated area: The case of Cava dei Selci (Latium, Italy)

“…The isotope composition of carbon was expressed as δ 13 C-CO 2 ‰ versus V-PDB. The adopted measurement method allowed to achieve precision for δ 13 C (CO2) of ± 0.15‰ (Di Martino et al, 2016).…”