[SIT22-P21] Sound velocity of Al-bearing hydrous and anhydrous bridgmanites under high pressure
Keywords:hydrous bridgmanite, anhydrous bridgmanite, lower mantle, Synchrotron X-ray in situ experiment, sound velocity
For the comparison, the sound velocity measurement of anhydrous bridgmanite is also important. However, even in the anhydrous bridgmanite, the substitution forms are complicated. We recognize that both “Tschermak substitution” and “oxygen-vacancy substitution” forms exist in anhydrous bridgmanite. So the special attention was made to synthesize the two different anhydrous bridgmanites by preparing the appropriate compositional starting materials and conducting experiments in extremely anhydrous condition.
We succeeded to synthesize the polycrystalline hydrous and anhydrous bridgmanites using the Kawai-type high pressure apparatus (Orange 3000) in Ehime University suitable for the sound velocity measurements. In situ ultrasonic experiments combined with X-ray were conducted in BL04B1 beamline, SPring-8. In this talk, we will explain the experimental results in details.