The pressure scale at multimegabar and the implication to the center of the Earth

兆巴压力等级及其对地心的影响

• 批准号: 21740374
• 负责人: SAKAI Takeshi
• 金额: $ 2.75万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21740374/
• 关键词: 地殻; マントル; 核; 地球中心核; 高温高圧; 圧力スケール; ダイヤモンドアンビルセル

We compressed NaCl-B2 to 304 Gpa and presented a pressure scale based on the Birch-Murnaghan and Vinet equations of state for this phase. The phase relations of Fe, Fe_<90>Ni_<10> and Fe_<87.9>Ni_<4.4>Si_<7.7> were investigated up to 273(6) Gpa and 4490(560) K, 250(19) Gpa and 2730(110) K and 304(3) Gpa and 2780(210) K, respectively, and the hexagonal close-packed structure was found to be stable in all of these compounds under the pressure and temperature conditions studied. The weak temperature dependency of the axial ratio of hcp-Fe-Ni-Si alloy indicates that the c-axis is still harder than the a-axis at high temperature condition. Therefore the alignment of hcp-Fe-Ni-Si alloy with the c-axis parallel to the Earth's rotation axis could account for the observation of the seismic wave anistropy of the inner core. On the other hand, Fe_<88.1>Ni_<9.1>S_<2.8> alloy was compressed up to 335 Gpa, and the hexagonal close-packed structure was found to be stable. Our results indicate that the hcp Fe-5 at.% Ni-7.9-10.3 at.% S alloy can account for the density of the inner core at 330 Gpa, assuming a linear relationship exists between the density and the nickel and sulfur content.

我们将 NaCl-B2 压缩至 304 Gpa，并基于该相的 Birch-Murnaghan 和 Vinet 状态方程提出了压力标度。研究了 Fe、Fe_<90>Ni_<10> 和 Fe_<87.9>Ni_<4.4>Si_<7.7> 在 273(6) Gpa 和 4490(560) K、250(19) Gpa 和 2730 时的相关系(110) K 和 304(3) Gpa 和 2780(210) K 分别，发现在所研究的压力和温度条件下，所有这些化合物的六方密堆积结构都是稳定的。 hcp-Fe-Ni-Si合金轴比的弱温度依赖性表明在高温条件下c轴仍然比a轴硬。因此，hcp-Fe-Ni-Si 合金的 c 轴与地球自转轴平行的排列可以解释对内核地震波各向异性的观测。另一方面，Fe_<88.1>Ni_<9.1>S_<2.8>合金被压缩至335Gpa，并且发现六方密排结构是稳定的。我们的结果表明，假设密度与镍和硫含量之间存在线性关系，hcp Fe-5 at.% Ni-7.9-10.3 at.% S 合金可以解释 330 Gpa 的内核密度。

项目成果

Compression study of S-bearing Fe-Ni alloy and(Fe,Ni)_3S up to the core pressure conditions

含硫Fe-Ni合金和(Fe,Ni)_3S在核心压力条件下的压缩研究

• 发表时间: 2010
• 作者: T.Sakai; E.Ohtani; H.Terasaki; S.Kamada; N.Hirao; N.Sata; Y.Ohishi
• 通讯作者: Y.Ohishi

Electronic correlations in dense iron: from moderate pressure to Earth’s core conditions

致密铁中的电子相关性：从中等压力到地核条件

• DOI: 10.1088/1361-648x/ab274f
• 发表时间: 2019-07-01
• 期刊: Journal of Physics: Condensed Matter
• 作者: L. Pourovskii

内核相当圧力までのNaCl-B2状態方程式

达到内核等效压力的 NaCl-B2 状态方程

• 发表时间: 2011
• 作者: 境毅; 大谷栄治; 平尾直久; 大石泰生
• 通讯作者: 大石泰生

Density of Fe-Ni-S alloy at the pressure of the center of the Earth

Fe-Ni-S合金在地心压力下的密度

• 发表时间: 2010
• 作者: Sakai; T.; Ohtani; E.; Terasaki; H.; Kamada; S.; Hirao; N.; Sata; N.; Ohishi; Y.
• 通讯作者: Y.

Micro sample preparation using Focused Ion Beam system for the experiment at multimegabar pressure

使用聚焦离子束系统制备微量样品，用于兆巴压力下的实验

• 发表时间: 2009
• 作者: Sakai; T.
• 通讯作者: T.