Systematics of the post-spinel tranisition in Fe-bearing compositions

含铁组合物中尖晶石后转变的系统学

• 批准号: 24942365
• 负责人: Professor Dr. Daniel J. Frost
• 金额: --
• 依托单位: Bayerisches Forschungsinstitut für Experimentelle Geochemie und Geophysik (BGI)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/24942365?language=en
• 关键词: Systematics; post; spinel; tranisition; Fe

Phases with the spinel structure occur in many fundamental chemical systems of geological importance and a number of these are known to undergo one or more phase transformations at transition zone and lower mantle pressures. The transformation mechanisms and crystal chemical factors controlling the formation of particular postspinel structures are poorly understood, as are the P-T stabilities of the post-spinel phases. Our goal is to address this knowledge deficit through a study combining in situ experiments (DAC and multi-anvil) at high P and T (10-25 GPa and up to 1600°C), with TEM characterisation (microstructures) and atomistic computer simulations. We will concentrate on relevant Fe-bearing systems: Fe3O4 (magnetite), Fe3O4-FeCr2O4 (magnetite-chromite) and FeAl2O4 (hercynite). Different theoretical approaches will be tested by comparison with experimental data. We seek to develop thermodynamic descriptions of the transformations, as well as understanding their mechanisms (by TEM). The resulting thermodynamic data will be used to calculate phase relations in these fundamental systems at high P and T. The implications of these transformations for natural systems will be explored.

尖晶石结构的相位发生在许多地质重要性的基本化学系统中，其中许多是在过渡区和较低地幔压力的一个或多个相变。控制特定后跨度结构形成的转化机制和晶体化学因子，以及后旋转阶段的P-T系统也很少了解。我们的目标是通过在高P和T（10-25 GPA和最高1600°C）上的原位实验（DAC和多ANVIL）的研究来解决这种知识防御，并具有TEM表征（微结构）和原子计算机模拟。我们将集中精力于相关的含含水系统：Fe3O4（磁铁矿），Fe3O4-Fecr2O4（磁铁矿 - 奇异石）和Feal2O4（Hercynite）。通过与实验数据进行比较，将测试不同的理论方法。我们试图开发有关转化的热力学描述，并了解其机制（通过TEM）。最终的热力学数据将用于计算高P和T下这些基本系统中的相位关系。将探讨这些转换对自然系统的影响。

项目成果

Detecting the spinel–post-spinel transition in Fe3O4 by in situ electrical resistivity measurements

• DOI: 10.1080/08957950903392092
• 发表时间: 2009-12
• 期刊: High Pressure Research
• 影响因子: 2
• 作者: K. Schollenbruch;A. Woodland;D. Frost;F. Langenhorst

The stability of hercynite at high pressures and temperatures

铁铝尖晶石在高压和高温下的稳定性

• DOI: 10.1007/s00269-009-0317-z
• 发表时间: 2009
• 期刊: Physics and Chemistry of Minerals
• 影响因子: 1.4
• 作者: Schollenbruch;Woodland AB;Frost DJ
• 通讯作者: Frost DJ

In situ determination of the spinel–post-spinel transition in Fe3O4 at high pressure and temperature by synchrotron X-ray diffraction

同步加速器X射线衍射原位测定高压高温下Fe3O4中的尖晶石-后尖晶石转变

• DOI: 10.2138/am.2011.3642
• 发表时间: 2011
• 期刊: American Mineralogist
• 影响因子: 3.1
• 作者: Schollenbruch K;Woodland AB;Frost DJ ;Wang Y;Sanehira T;Langenhorst
• 通讯作者: Langenhorst