Properties of Fe-bearing geomaterials at conditions close to the core-mantle boundary

接近核幔边界条件下含铁岩土材料的特性

• 批准号: 521549147
• 负责人: Dr. Karen Appel
• 金额: --
• 依托单位: National Accelerator Laboratory SLAC
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/521549147?language=en
• 关键词: Properties; Fe; bearing; geomaterials; conditions

Structural and electronic properties of rock forming minerals studied at in situ conditions are the key to understand processes inside the Earth including chemistry and dynamics at the core-mantle boundary and core formation. In this project we use X-ray emission spectroscopy to learn about the electronic state and X-ray diffraction to determine the corresponding atomic structure of material at conditions of the core-mantle boundary. We aim also to pioneer the application of new methods at these conditions like valence-to-core emission and X-ray Raman scattering. Latter has the potential to add structural information also for light elements. To reach and densely cover the p-T space of up to 400 GPa and several 1000 K, we apply X-ray heating of material compressed in diamond anvil cells as well as dynamic laser compression techniques. We make use of a new experimental facility, the High-Energy Density Science instrument at the European XFEL GmbH. In the first part of this project, we will focus on solid material and apply static compression techniques. In the second phase we aim at investigating molten material and will apply dynamic compression techniques that have the potential of reaching highest achievable pressures and temperatures in the laboratory. We will focus our study on solid solutions of FeO and MgO, namely on (MgxFe1-xO) with x around 0.8 as this mineral is assumed to be the second-most abundant mineral phase of the lower mantle of the Earth.

在原位条件下研究的造岩矿物的结构和电子特性是了解地球内部过程的关键，包括地核-地幔边界和地核形成的化学和动力学。在这个项目中，我们使用X射线发射光谱来了解电子态和X射线衍射，以确定核幔边界条件下材料相应的原子结构。我们的目标还包括在这些条件下率先应用新方法，例如价核发射和 X 射线拉曼散射。后者还有可能为轻元素添加结构信息。为了达到并密集覆盖高达 400 GPa 和几个 1000 K 的 p-T 空间，我们对金刚石砧座中压缩的材料进行 X 射线加热以及动态激光压缩技术。我们利用欧洲 XFEL GmbH 的新实验设施，即高能密度科学仪器。在该项目的第一部分中，我们将重点关注固体材料并应用静态压缩技术。在第二阶段，我们的目标是研究熔融材料，并将应用动态压缩技术，该技术有可能达到实验室中可达到的最高压力和温度。我们将重点研究 FeO 和 MgO 的固溶体，即 x 约为 0.8 的 (MgxFe1-xO)，因为这种矿物被认为是地球下地幔第二丰富的矿物相。