Structure strength and elasticity of planetary materials at very high pressure

行星材料在极高压力下的结构强度和弹性

• 批准号: 314540-2006
• 负责人: Shieh, Sean
• 金额: $ 1.67万
• 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: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=365583
• 关键词: Structure; strength; elasticity; planetary; materials

The recent discovery of the new post-perovskite phase (MgSiO3) at 125 GPa and 2500 K, corresponding to 2700 km depth in the Earth, has attracted considerable attention.  The perovskite phase has been believed to be the prevailing phase in the Earth's lower mantle for decades and now, the new discovery reveals that we need to re-examine other important mantle phases in order to better understand the Earth's structure and dynamics.  In this proposal, the structure, strength, and elasticity of Fe- and Al-bearing MgSiO3 perovskite and CaSiO3 perovskite phases at lower mantle pressure and temperature conditions will be studied.  The high-pressure diamond anvil cell, together with a laser heating system, will be used for these experimental investigations of important planetary materials.  Moreover, the newly developed radial x-ray diffraction method, together with lattice strength theory, will provide a wealth of new information on materials under high-pressure and high temperature conditions.   Due to the flexibility and varied capability of high pressure diamond-anvil cell experimentation, gaseous-type and liquid-type constituents of the Jovian satellites and giant planets will also be investigated at extreme conditions, i.e. pressure up to 200 GPa and temperature ~2000-3000 K.  The results obtained in this proposed research will help to better understand and model the structure and dynamics of the Earth and other planets.

最近在125 GPa和2500 K（相当于地球深度2700公里）下发现的新的后钙钛矿相（MgSiO3）引起了人们的广泛关注。  几十年来，钙钛矿相一直被认为是地球下地幔的主要相，现在，新发现表明，我们需要重新检查其他重要的地幔相，以便更好地了解地球的结构和动力学。  在本提案中，将研究较低地幔压力和温度条件下含铁和含铝的 MgSiO3 钙钛矿和 CaSiO3 钙钛矿相的结构、强度和弹性。  高压金刚石砧室与激光加热系统一起将用于重要行星材料的实验研究。  此外，新开发的径向X射线衍射方法与晶格强度理论一起，将为高压高温条件下的材料提供丰富的新信息。   由于高压金刚石砧室实验的灵活性和多样化能力，木星卫星和巨行星的气态和液态成分也将在极端条件下进行研究，即压力高达 200 GPa 和温度约 2000-3000 K。这项拟议研究中获得的结果将有助于更好地理解和模拟地球和其他行星的结构和动力学。