金属酸盐分区的压力依赖性解释了地幔丰富的
Nagi Ikuta1, Naoya Sakamoto2, Shoh Tagawa3
1Department of Earth and Planetary Science, The University of Tokyo, Tokyo, 113-0033, Japan. ikuta-nagi464@g.ecc.u-tokyo.ac.jp.
Scientific reports
|January 12, 2024
概括
(P) 的金属/分离系数在高压下发生显著变化,表明地球是地球.
科学领域:
- 地质化学 地质化学
- 高压实验石油学 高压实验石油学
- 星球科学 星球科学
背景情况:
- 之前的研究表明,在地球核心中含有高 (P),除非 (Si) 丰富.
- 了解的行为对于核心形成模型至关重要.
研究的目的:
- 在极端压力 (27-61 GPa) 和温度 (3820-4760 K) 下研究的金属/酸盐分离系数 (DP).
- 改进地球核心形成和含量的模型.
主要方法:
- 高压,高温实验模拟核心形成条件.
- 使用高分辨率成像和二次离子质谱分析回收样本.
主要成果:
- 在15GPa以上,DP的压力依赖性从正向负转变.
- 这种变化归因于酸盐在高压下化的P5+的协调数增加.
结论:
- 新的分区数据表明,大约有0.2%的重量%P在地球的核心.
- 这与地化学估计一致,并支持核心形成模型,而不需要金属中大量.
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