Evidence of Tectonic Control on the Geochemical Features of the Volatiles Vented along the Nebrodi-Peloritani Mts (Southern Apennine Chain, Italy)

Figure 5

CO₂ content vs. δ¹³C_TDC. The plot shows carbon isotopic fractionation due to the occurrence of GWI interactions and degassing. The chemical fractionation due to CO₂ dissolution during GWI induces isotopic fractionation of the carbon species. The evidence that the higher the CO₂ content in the dissolved gases, the lower the isotopic composition of the TDC, indicates that the origin of the dissolved carbon is mainly due to the preferential dissolution of the heavy carbon isotope as bicarbonate ion. Samples from the Southern Apennines (grey crosses) after Italiano et al. [60]; samples from the Eastern Alps (grey squared symbols) after Italiano et al. [47]. Other symbols are as in Figure 2.