Theoretical and Experimental Investigation of Low-temperature Magnetic Phase Transitions and Application to Paleomagnetism

低温磁相变的理论与实验研究及其在古地磁学中的应用

• 批准号: 9814396
• 负责人: Lisa Tauxe
• 金额: $ 13.4万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2000-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9814396&HistoricalAwards=false
• 关键词: Theoretical; Experimental; Investigation; Low; temperature

9814396 Tauxe Low-temperature magnetic measurements are increasingly used in applications of rock magnetism to studies of plate tectonics, the history of the Earth's magnetic field and global environmental change. These measurements make use of phase transitions that occur below room temperature in some magnetic minerals. The investigators will develop the first quantitative theory for changes in magnetic remanence across phase transitions. The theoretical work will place strong constraints on possible mechanisms for pseudo-single-domain remanence and acquisition of thermoremanent magnetization. Combining theoretical and experimental work, the investigators will use low temperature demagnetization to improve paleointensity measurements and provide a physical interpretation of remagnetization in Paleozoic carbonates.

9814396陶克斯低温磁测量越来越多地应用于岩石磁学研究板块构造、地球磁场历史和全球环境变化。这些测量利用了一些磁性矿物在室温以下发生的相变。研究人员将开发第一个关于相变过程中剩磁变化的定量理论。理论工作将对伪单磁畴剩磁的可能机制和热剩余磁化的获得施加强烈的约束。结合理论和实验工作，研究人员将利用低温退磁来改进古强度测量，并对古生代碳酸盐的再磁化提供物理解释。