R3: High-pressure science and deep Earth’s material

[R3-07] The effect of water on the high-pressure phase transition of pyroxene–garnet system

*Yasushi Ueno¹, Toru Inoue¹, Masamichi Noda², Sho Kakizawa¹, Takaaki Kawazoe¹, Tomoko Sato¹, Toru Shinmei³, Tetsuo Irifune³, Koji Ohara⁴ (1. Hiroshima Univ. Adv. Sci. Eng., 2. Hiroshima Univ. Sci., 3. Ehime Univ. GRC, 4. JASRI)

Keywords:pyroxene-garnet system, bulk glass, wet condition, garnet-bridgmanite, akimotoite-bridgmanite

We conducted high pressure and high temperature experiments in the pyroxene-garnet system under anhydrous and hydrous conditions. We used glass rod and oxide mixture as the starting materials for dry and wet conditions, respectively. As a result, the akimotoite - bridgmanite boundary shifted to lower pressure side by the effect of water. In addition, the amount of Al₂O₃ in garnet was much larger than that in previous studies. Further investigation of this result is in progress.