Kinetics of Metamorhpic Processes in the Contact Aureoles of Basalt Feeder Dikes, Killala Bay, Ireland

爱尔兰基拉拉湾玄武岩馈线堤接触光环的变质过程动力学

• 批准号: 8817254
• 负责人: Raymond Joesten
• 金额: $ 3.5万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-02-15 至 1991-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8817254&HistoricalAwards=false
• 关键词: Kinetics; Metamorhpic; Processes; Contact; Aureoles

Emplacement of basaltic feeder dikes in limestone at Killala Bay produced grossular- and wollastonite-bearing assemblage in the aureoles of small (1.5 and 5.3m) dikes and in the outer aureole of a 50m dike, which has very high temperature assemblages in its inner aureole and which has assimilated limestone along its contact. Numerical modelling of the thermal histories of these aureoles allows them to be used as natural experiments from which kinetic parameters for the coarsening of calcite, wollastonite and quartz can be recovered. Pressure, temperature, fluid composition and fluid/rock ratio in the aureoles will be determined using stratigraphy, mineral assemblages and compositions, and thermochemical and reaction-progress calculations for buffer assemblages so that a numerical thermal history model involving multiple episodes of feeder flow, magmatic crystallization and cooling can be calibrated. Measured grain-size distributions will be use to distinguish the coarsening mechanisms of Ostwald ripening and normal grain growth, and the variation of the mean grain size with distance from the contact will be used to retrieve material constants and activation energies for grain growth. This work will "calibrate" the natural laboratory for the analysis of the kinetics of wollastonite and grossular nucleation and annealing of quartz dislocations in future studies.

基拉拉湾石灰岩中玄武岩补给岩脉的就位 产生了钙铝榴石和硅灰石轴承组合， 小岩脉（1.5和5.3米）的光环和外光环 一个50米的堤坝，其中有非常高的温度组合在其 内部光环，并已同化石灰石沿着其 contact. 这些热历史的数值模拟 光环使它们能够被用作自然实验， 方解石、硅灰石粗化动力学参数 并且可以回收石英。 压力、温度、流体 组成和流体/岩石比例的光环将是 利用地层学、矿物组合和 成分、热化学和反应过程 计算缓冲器组件，以便数值热 历史模型包括多个支线流事件， 岩浆结晶和冷却可以被校准。 测量 粒度分布将用于区分 Ostwald熟化和正常晶粒粗化机理 生长，以及平均晶粒尺寸随距离的变化 将用于检索材料常数， 晶粒生长的活化能。 这项工作将“校准” 自然实验室的动力学分析 硅灰石和钙铝榴石的成核和退火 在今后的研究中，