S3：北東アジアの鉱物・岩石・資源 （スペシャルセッション）

[S3P-03] モンゴル北西部・ハンホヒン山地に産する泥質片麻岩に含まれるザクロ石中のクリストバライト包有物

*足立 達朗¹、小山内 康人¹、中野 伸彦¹、Syeryekkhaan Kundyz¹、Jargalan Sereenen²、大和田 正明³、Satish-Kumar M.⁴ (1. 九州大、2. モンゴル科技大、3. 山口大、4. 新潟大)

キーワード：クリストバライト，泥質片麻岩，ハンホヒン山地，モンゴル

Cristobalite inclusions were found in garnet in garnet-sillimanite-biotite gneiss from the Hanhohiyn Mountains, northwestern part of Mongolia. Cristobalite is preserved in the core portion of garnet and is as a prograde mineral assemblage. Fine-grained cristobalite inclusions are found with chlorite, pyrophyllite and quartz in garnet. Cristobalite occurring with minerals stable under low-temperature condition suggests that garnet should grow at a faster rate than transition from cristobalite to quartz.