Shear Deformation of Upper Mantle Minerals: The Role of Water, Dynamic Recrystallization and Deformation

上地幔矿物的剪切变形：水的作用、动态重结晶和变形

• 批准号: 9706329
• 负责人: Shun-ichiro Karato
• 金额: $ 19.07万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 1999-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9706329&HistoricalAwards=false
• 关键词: Shear; Deformation; Upper; Mantle; Minerals

9706329 Karato The PI proposes to provide new experimental constraints on the geodynamical interpretation of seismic anisotropy in upper mantle minerals. The focus will be on the role of water and of dynamic recrystallization. Simple shear deformation techniques developed in the PI's laboratory will be used in the experiments and electron backscatter pattern analysis (EBSP) will be utilized to investigate lattice preferred orientation. Synthetic polycrystalline specimens of upper mantle minerals will be prepared and deformed to large strains (~100-300 %) at high temperature and pressure in simple shear under water-rich and water-poor conditions. The microstructural development including the lattice preferred orientation will be investigated by the EBSP technique and seismic anisotropy corresponding to specific deformation mechanisms and deformation geometry will be predicted. The results will be compared with seismological observations to place new constraints on the flow pattern in the upper mantle. ***

小行星9706329 PI建议为上地幔矿物中地震各向异性的地球动力学解释提供新的实验约束。 重点将放在水和动态重结晶的作用。 PI实验室开发的简单剪切变形技术将用于实验，电子背散射图案分析（EBSP）将用于研究晶格择优取向。 将制备上地幔矿物的合成多晶样品，并在高温高压下在富水和贫水条件下在简单剪切中变形至大应变（~100- 300%）。 将通过EBSP技术研究包括晶格择优取向在内的微结构发展，并预测对应于特定变形机制和变形几何形状的地震各向异性。 研究结果将与地震学观测结果进行比较，从而对上地幔的流动模式提出新的限制。 ***