The episodic and abrupt geochemical changes at La Fossa fumaroles (Vulcano Island, Italy) and related constraints on the dynamics, structure, and compositions of the magmatic system

Seismically triggered anomalies in the isotope signatures of mantle‐derived gases detected at degassing sites along two neighboring faults in NW Bohemia, central Europe

“…The situation is further complicated by the possibility that different forms of carbon (CO 2 ; CO 3 2− ) may coexist within the melt. The carbon fractionation effect may then also depend on the mixing ratio of the two components within the melt [e.g., Paonita et al ., and references therein].…”

Geochemistry of fluid discharges from Peteroa volcano (Argentina-Chile) in 2010–2015: Insights into compositional changes related to the fluid source region(s)

“…After standard purification procedures, Ne was cryogenically separated from Heat 77 K by absorption in a charcoal trap cooled at 12 K. The abundances and isotope compositions of He, as well as the 4 He/ 20 Ne ratios, were then determined by separately admitting He and Ne into a split flight tube mass spectrometer (Helix SFT). The analytical error was ≤ 0.3% (Paonita et al, 2013). The measured R/Ra values were corrected for atmospheric contamination using the 4 He/ 20 Ne ratios (Poreda and Craig, 1989), as follows: Ar/ 36 Ar ratios in the 2012 gas samples were determined at the INGV laboratories of Naples (Italy) using an Agilent 6890N gas chromatograph (GC) coupled with a Finnigan Delta plusXP continuous-flow mass spectrometer (MS).…”

“…In fact, a gas phase released from strongly degassed magma is typically enriched in species characterized by high solubility in silicate melt (e.g., Cl and S). Recent works (Paonita et al, 2012(Paonita et al, , 2013Caliro et al, 2014) have shown that ratios among inert gases and CO 2 can be used to recognize signatures of magma degassing and quantify the degassing degree, even in fumarolic fields where the contribution from underlying hydrothermal systems is significant. According to the relative solubility of Cl N S N CO 2 N He N N 2 in water, the N 2 /He ratios are virtually unaffected by interaction with hydrothermal liquids even in gas phases that have suffered a complete removal of Cl and S (Liotta et al, 2010;Paonita et al, 2012).…”

Spatial Distribution of Field Physico-Chemical Parameters in the Vulcano Island (Italy) Coastal Aquifer: Volcanological and Hydrogeological Implications

“…Indeed, one of the most important chemical processes, which characterizes the ionic content of the Vulcano groundwater, is the contribution of the fumarolic gases [13][14][15][16][17][18][19][20][21][22][23][24].…”