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

[R3-05] High-temperature heat capacity measurement of Mg₂SiO₄ wadsleyite

*Hiroshi Kojitani¹, Yuki Tsunekawa¹, Masaki Akaogi¹ (1. Gakushuin Univ. Sci.)

Keywords:wadsleyite, heat capacity, DSC, thermoelastic parameter, lattice vibrational model calculation

Mg₂SiO₄ wadsleyite (Wd) is one of major constituent minerals in the Earth’s mantle transition zone. In this study, we performed high-temperature heat capacity measurement of synthetic Wd using the DSC method in the temperature range of 300-820 K with 10 K interval. The present heat capacity data are 2-5% larger than those by previous measurements. This result shows that the previous high-temperature heat capacity of Wd was underestimated. Furthermore, uisng optimized thermoelastic parameters, heat capacity of Wd was extrapolated by the lattice vibrational model calculation.