日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

セッション記号 S (固体地球科学) » S-IT 地球内部科学・地球惑星テクトニクス

[S-IT25] Planetary cores: Structure, formation, and evolution

2019年5月30日(木) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:寺崎 英紀(大阪大学大学院理学研究科)、大谷 栄治(東北大学大学院理学研究科地学専攻)、William F McDonough(University of Maryland College Park)、George Helffrich(Earth-Life Science Institute, Tokyo Institute of Technology)

[SIT25-P05] Phase relations in the Fe-Ni-Si system at high pressures and high temperatures

*生田 大穣1大谷 栄治1河口 沙織2平尾 直久2大石 泰生2 (1.東北大学大学院理学研究科地学専攻、2.(公財)高輝度光科学研究センター 利用研究促進部門)

キーワード:Fe-Ni-Si系、相関係、高圧

The Earth's core has supposed to be constituted by iron-nickel alloys with some light elements. Silicon is one of the most convincing candidates among the light elements. Therefore, the study of high pressure and high temperature properties and behaviors for the Fi-Ni-Si system is important in understanding and constraining to the properties of the Earth's core. In this study, high pressure and high temperature properties for three different contents of Fe-Ni-Si alloys were investigated by using laser heated diamond anvil cells and in situ X-ray diffraction with synchrotron radiation. We determined the phase relations of Fe(0.94-x)Ni0.06Six (x = 0.10, 0.17, 0.26) up to 166 GPa and 2800 K, respectively. According to previous Fe-Si system studies, Fe0.83Si0.17 alloys transform from hcp to hcp+B2 and fcc+hcp+B2 phases with increasing temperature in isobaric conditions. We observed the change in temperature increase and positive slope of these boundaries due to the nickel containing effect and the difference in silicon content. We report the details of phase relations in the Fe-Ni-Si system and discuss with the differences from the Fe-Si system.