2019 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)
Sep 19 - Sep 23, 2019Kyushu University Ito Campus
2019 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)
Sep 19 - Sep 23, 2019Kyushu University Ito Campus
[S1-05]Melt inclusions in a gabbro xenolith of the Izu-Oshima 1986 eruption
*Hidemi Ishibashi1, Oida Ryoya1, Atsushi Yasuda2, Natsumi Hokanishi2, Tatsuro Chiba3(1. Shizuoka Univ., Sci, 2. Univ. Tokyo, ERI, 3. Asia Air Survey)
Keywords:
Melt inclusions,Crystal mush,gabbro,Izu-Oshima,eruption
We investigated compositions of interstitial melt (IM) and melt inclusions (MI) in a gabbro xenolith of the Izu-Oshima 1986 eruption. The IM shows striped patterns of chemical heterogeneity with compositions similar to those found in the 1986 B magma indicating interstitial melt mixing in a crystal mush. MIs show constant K/Ti and Ca/Al ratios, which values are the same with those of magmas with SiO2 <56 wt.% of Izu-Oshima volcano, indicating the original interstitial melt had SiO2 < 56wt.%.