Water solubility in trachytic and pantelleritic melts: an experimental study

Solubility experiments were performed on a trachyte and pantellerite from Pantelleria. The has SiO 2 =65.2 wt%, Al O 3 =15.2 wt% peralkaline index (P.I.=molar[(Na O+K O)/Al ])∼1 while the =72.2 =11 P.I.=1.3. in pressure range of 50–300 MPa at T=950°C for 50–200 T=850°C pantellerite. water content experimental glasses was determined by Karl Fischer titration, elemental analyser FT–IR spectroscopy. Water appears similar both compositions analogous conditions, varying ∼2.5 50 to ∼5.8 200 MPa. Comparison data with thermodynamic models shows that empirical model Moore et al. [1998] better matches compositions, Papale [2006] Ghiorso Gualda [2015] tend overestimate melt content, probably due paucity used calibration. One inference these new solubility is MI-derived depth felsic reservoirs Pantelleria which deepens 2.4 3.5 km.