Experimental Studies in the Kinetics of Petrologic Processes

岩石过程动力学实验研究

• 批准号: 9804794
• 负责人: E. Bruce Watson
• 金额: $ 51.24万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-15 至 2003-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9804794&HistoricalAwards=false
• 关键词: Experimental; Studies; Kinetics; Petrologic; Processes

9804794WatsonThere are two main thrusts in this broad-based experimental investigation of kinetic phenomena in materials of the Earth's crust and upper mantle: studies of lattice diffusion in minerals and of textural aspects of fluid-bearing and partially-molten rocks. The diffusion studies focus upon intracrystalline transport of key trace elements and radiogenic isotopes (e.g., Pb, Sr, rare earths) in major rock-forming minerals (olivine, pyroxene, garnet), and also upon specific phenomena such as the isotopic (mass) effect on diffusion and diffusion in the near-surface region (i.e., the outermost 10-100 monolayers). The textural studies are aimed at evaluating the importance of interfacial energy minimization in determining the manner in a which a fluid phase is distributed between mineralogically distinct units in close proximity to one another (i.e., fluid "partitioning"), and also at understanding the coarsening behavior of mineral grains in the presence of a small amount of fluid. Ultimately, it is hoped that the diffusion data will place time and temperature constraints on inter-mineral isotopic and trace-element equilibration, and that the textural information will help petrologists and geochemists deduce the nature of fluid- and melt-rock interaction at depth in the Earth.

9804794Watson 在这项对地壳和上地幔材料的动力学现象的广泛实验研究中，有两个主要推力：矿物中晶格扩散的研究以及含流体和部分熔融岩石的结构方面的研究。扩散研究重点关注主要造岩矿物（橄榄石、辉石、石榴石）中关键微量元素和放射性同位素（例如，Pb、Sr、稀土）的晶内传输，以及特定现象，例如同位素（质量）对扩散的影响以及近地表区域（即最外层的 10-100 个单层）的扩散。结构研究的目的是评估界面能量最小化的重要性，以确定流体相在彼此非常接近的矿物学不同单元之间的分布方式（即流体“分配”），并了解存在少量流体时矿物颗粒的粗化行为。最终，希望扩散数据能够对矿物间同位素和微量元素平衡施加时间和温度限制，并且结构信息将帮助岩石学家和地球化学家推断地球深处流体和熔岩相互作用的性质。