S1: Earth materials science in igneous processes (Special Session)

[S1-04] Analysis of volatiles in melt inclusions of the Myoko Sekiyama (43 ka) and Kannoki (41 ka) eruptions

*Morihisa Hamada¹, Estelle F. Rose-Koga², Kenneth T. Koga², Takayuki Ushikubo¹, Kenji Shimizu¹, Hideo Harada³, Yoshiaki Yamaguchi³ (1. JAMSTEC, 2. Laboratoire Magmas et Volcans, 3. Shinshu University)

Keywords:Myoko volcano, Rear-arc volcano, Melt inclusions, Volatiles, SIMS

We analyzed melt inclusions collected from scoriae of the Myoko Sekiyama (43 ka) and Kannoki (41 ka) eruptions by SIMS. Olivine-hosted basaltic melt inclusions from both eruptions dissolve up to 6 wt.% H₂O. Their H₂O concentration decreases with increasing SiO₂. Halogen concentration in melt inclusions from both eruptions are different, suggesting that the fertility of source mantle and/or amount of supplied slab-derived fluids are different between the two eruptions.