Fig. 8From: Behavior of magmatic components in fumarolic gases related to the 2018 phreatic eruption at Ebinokogen Ioyama volcano, Kirishima Volcanic Group, Kyushu, JapanSchematic illustration of local meteoric water (LW) in the shallow aquifer (Aq) beneath Ioyama volcano interacting with magmatic vapor (MV). MV is discharged from the shallow magma chamber (SMH). MV moves up through the sealing zone (SZ), the magmatic vapor reservoir (MVR), and caprock (CR). MV produces volcanic earthquakes (Eq) in the region between MVR and CR. Interactions between MV and LW produce the vapor phase (Vp) and the liquid phase (Lp). A portion of both the Vp and Lp are discharged at the surface as fumarolic gas (FG) and hot spring water (HS), respectively. A portion of the SO2 in MV is converted to SO42– ion and H2S gas, which are preferentially distributed to Lp and Vp, respectivelyBack to article page