Experimental earth and planetary materials sciences at extreme conditions of pressure and temperature

极端压力和温度条件下的实验地球和行星材料科学

• 批准号: 105604-2008
• 负责人: Secco, Richard
• 金额: $ 3.72万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=421742
• 关键词: Experimental; earth; planetary; materials; sciences

The proposed research is a multi-pronged experimental investigation aimed at understanding the composition, state and core dynamics of Earth, Mercury, Mars and Jupiter's satellites Io and Ganymede. The central parts of these planetary bodies are composed primarily of iron and its dilute alloys of sulfur and silicon. The physical properties of these liquid iron alloys control fundamental processes such as heat flow from the core to the mantle as well as the generation and maintenance of magnetic fields inside their cores. The guiding principle of our approach is that understanding the macro-scale processes that govern global geodynamics pivots on our knowledge of the micro-scale aspects of the mineral physics and chemistry of planetary materials that control them. The research will involve experimental measurements of the electrical resistivity, density and viscosity of liquid iron-sulfur-silicon alloys and analog materials at extreme pressures (20GPa) and temperatures (2500K) in large volume presses to simulate the conditions deep inside these planetary bodies. Additional studies of partitioning of U and Si isotopes between liquid metal and silicate will be carried out. With a planned team of 10 HQP over the period of the proposal, we will employ novel techniques developed in our lab to measure density and viscoity using composite spheres in the sink/float method. Synchrotron x-ray radiography will provide real-time images of the sphere motion in the pressurized liquid. The significance of the results is expected in three areas of deep Earth and planetary studies. 1. The results will help to determine the core compositions of these bodies. 2. The measured physical properties are required for accurate models of the dynamics (geodynamo and heat flow) of the cores of these planetary bodies. 3. The results will directly address the basic physics of constant physical property behavior along the pressure-dependent melting boundary.

拟议的研究是一项多管齐下的实验研究，旨在了解地球、水星、火星和木星卫星木卫一和木卫三的组成、状态和核心动力学。这些行星体的中心部分主要由铁及其硫和硅的稀合金组成。 The physical properties of these liquid iron alloys control fundamental processes such as heat flow from the core to the mantle as well as the generation and maintenance of magnetic fields inside their cores.我们方法的指导原则是，理解控制全球地球动力学的宏观过程取决于我们对控制它们的行星材料的矿物物理和化学的微观方面的了解。该研究将涉及在大容量压力机中在极端压力（20GPa）和温度（2500K）下对液态铁硫硅合金和模拟材料的电阻率、密度和粘度进行实验测量，以模拟这些行星体深处的条件。将进一步研究液态金属和硅酸盐之间 U 和 Si 同位素的分配。在提案期间，我们计划组建由 10 名 HQP 组成的团队，我们将采用实验室开发的新技术，通过沉/浮法中的复合球来测量密度和粘度。同步加速器 X 射线照相术将提供加压液体中球体运动的实时图像。预计这些结果将在地球深层和行星研究的三个领域发挥重要作用。 1. 结果将有助于确定这些机构的核心组成。 2. 测量的物理特性对于这些行星体核心的动力学（地球发电机和热流）的精确模型是必需的。 3. 结果将直接解决沿压力相关熔化边界的恒定物理性质行为的基本物理问题。