Collaborative Research: COMPRES Grand Challenge for Experimental Study of Plastic Deformation under Deep Earth Conditions

合作研究：深部地球条件下塑性变形实验研究的 COMPRES 大挑战

• 批准号: 0135411
• 负责人: Harry Green
• 金额: $ 80.45万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-15 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0135411&HistoricalAwards=false
• 关键词: Collaborative; Research; COMPRES; Grand; Challenge

Green0135411Quantitative rheological measurements on Earth materials have been conducted only under relatively low-pressure conditions corresponding to the depth of ~60 km or less. The main thrust of this project is to extend this limit, through technical developments, at least to ~800 km covering not only the upper mantle but also the transition zone and the lower mantle. We propose to establish a new inter-institutional program coordinated with COMPRES (Consortium for Materials Property Research in the Earth Sciences) by utilizing the infrastructure for operation of national facilities and educational program, and we will expand the capabilities of these facilities for the broader scientific community. Through inter-institutional collaboration, we will develop two new types of apparatus (a modified cubic apparatus (D-DIA) and a rotational Drickamer apparatus (RDA)) in addition to further improvements to the well-established deformation techniques using a multianvil apparatus (MA). Both D-DIA and RDA (as well as MA) can readily be fitted to synchrotron radiation facilities to allow quantitative measurements of stress and strain at high-pressure and temperature conditions. D-DIA is suited for quantitative rheology measurements including shear localization and resultant instabilities while RDA has a unique capability of large strain deformation experiments at high-pressures, an important feature for study of lattice preferred orientation. These apparatus will be used to obtain the first quantitative data set on rheological properties and deformation-induced microstructures of Earth and planetary materials under high-pressure, high-temperature conditions (to ~15-25 GPa, ~2000 K). The results of such measurements will contribute to better understand (i) the radial and lateral variation of rheological properties for whole mantle, (ii) the interaction of rheological behavior with chemical reactions including phase transformations, and (iii) the nature of deformation-induced microstructures such as lattice preferred orientation (which causes seismic anisotropy). The unique facility thus developed will be accessible to a large mineral and rock physics community and will significantly enhance the contribution of mineral and rock physics research to a wide range of solid Earth sciences.

Green0135411 对地球材料的定量流变测量仅在相对低压条件下（对应于约 60 公里或更小的深度）进行。该项目的主要目的是通过技术发展将这一限制扩展至至少约800公里，不仅覆盖上地幔，还覆盖过渡带和下地幔。我们建议利用国家设施和教育项目运营的基础设施，与 COMPRES（地球科学材料特性研究联盟）协调建立一个新的机构间项目，并且我们将为更广泛的科学界扩展这些设施的能力。通过机构间合作，除了使用多砧装置（MA）进一步改进成熟的变形技术外，我们还将开发两种新型装置（改进的立方装置（D-DIA）和旋转Drickamer装置（RDA））。 D-DIA 和 RDA（以及 MA）都可以轻松安装到同步加速器辐射设施上，以便在高压和高温条件下定量测量应力和应变。 D-DIA 适用于定量流变测量，包括剪切局部化和由此产生的不稳定性，而 RDA 具有高压下大应变变形实验的独特能力，这是研究晶格择优取向的重要特征。这些设备将用于获得第一个关于高压、高温条件下（~15-25 GPa，~2000 K）下地球和行星材料的流变特性和变形引起的微观结构的定量数据集。此类测量的结果将有助于更好地了解（i）整个地幔流变特性的径向和横向变化，（ii）流变行为与化学反应（包括相变）的相互作用，以及（iii）变形引起的微观结构的性质，例如晶格择优取向（导致地震各向异性）。由此开发的独特设施将可供大型矿物和岩石物理学界使用，并将显着增强矿物和岩石物理学研究对广泛的固体地球科学的贡献。