铁烯酶在下层地幔中的稳定性
Dubrovinsky1, Dubrovinskaia, Saxena
1Institute of Earth Sciences, Uppsala University, S-752 36 Uppsala, Sweden. European Synchrotron Radiation Facility (ESRF), BP 220, F-38043 Grenoble Cedex, France.
概括
铁烯酸,一个关键的下层地幔矿物质,在极端的压力和温度下,可以分解成不同的富含和富含铁的阶段. 这种分离可能会带来动态效应,导致地幔异质性.
科学领域:
- 地质物理学 地质物理学
- 矿物物理 矿物物理
- 地球科学 地球科学 地球科学
背景情况:
- 铁烯酸是地球下层地幔的主要组成部分.
- 了解其在地幔条件下的稳定性和行为对于解释地震数据和建模地幔动态至关重要.
研究的目的:
- 在高压和高温下研究铁烯酶固体溶液的稳定性和潜在解离.
- 模拟与地球下层地幔相关的条件.
主要方法:
- 加热铁烯酸酶样本 ((Mg(0.60) Fe ((0.40)) O和 (Mg(0.50) Fe ((0.50)) O) 到1000克尔文,温度为86千兆卡路里.
- 使用现场X射线衍射在Mao-Bell型钻石天细胞中.
主要成果:
- 铁烯酶样本显示出可能分裂成富含和富含铁的氧化物成分.
- 观测到的分解为在下层地幔条件下的矿物行为提供了洞察力.
结论:
- 铁烯酶的分解成不同的相可以导致密度变化.
- 这些密度差异可能会推动动态过程,导致地球地幔内的化学和物理异质.
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