Melts, fluids, crystals: Equilibrium and disequilibrium processes in magmatic systems and ore deposits

熔体、流体、晶体：岩浆系统和矿床中的平衡和不平衡过程

• 批准号: RGPIN-2015-06355
• 负责人: Baker, Don
• 金额: $ 3.64万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=614100
• 关键词: Melts; fluids; crystals; Equilibrium; disequilibrium

This research programme investigates processes involving volatiles and their interactions with crystals and melts in magmatic systems. I, together with students and colleagues, will investigate volatile exsolution from melts to form bubbles, develop new ways to estimate volatiles in ancient magmas and degassed into the atmosphere, explore the role of minor volatiles in volcanic eruptions, quantify the ability of volatiles to transport Cl, S and ore metals at magmatic conditions and explore their influence on the delayed nucleation of crystals in magmatic systems. This research program is centred around experimental measurements and computer simulations, and involves collaboration with colleagues working in the field. More specifically, the goals of this research program for the next five years are to: 1. Quantify the partitioning of sulfur and halogens between melts and aqueous fluids in experiments to measure the solubility of the minor volatiles and their effects on the ability of hydrous fluids to transport critical ore metals (e.g., Pt, Sc, Li, rare earth elements, etc.). 2. Measure the partitioning of minor volatiles (sulfur and halogens) between experimentally produced silicate melts and nominally volatile-free minerals (e.g., feldspar, clinopyroxene, olivine) in order to constrain pre-eruption magmatic volatile concentrations. The experimental results will be combined with measurements on natural minerals to estimate the volatile release from ancient flood basalts and those results provided to atmospheric scientists for modelling the effects of flood basalts on the terrestrial environment. 3. Investigate the role of minor volatiles on the exsolution (nucleation and growth) of bubbles from melts and their role in the initiation of volcanic eruptions through laboratory experiments and X-ray microtomographic studies. These measurements will be combined with computer models to determine the effects of different bubble size distributions on the permeabilities and strengths of magmatic foams. 4. Determine the role volatiles play in the supersaturation of magmatic melts with respect to crystallization of ore-rich minerals (e.g., sulfide, spodumene, iron oxides) and the formation of pegmatites through experimental studies of crystal nucleation and growth. This research program will provide us with an improved picture of how volatiles behave and the role they play in magmatic systems. In five years we will better understand volatiles in magmas and will have advanced our abilities to model the evolution of magmas, the magmatic degassing of pre-historic eruptions, the formation of magmatic ore deposits, and the eruption of volcanoes.

该研究计划调查涉及挥发物的过程及其与岩浆系统中的晶体和熔体的相互作用。我，与学生和同事一起，将调查从熔体挥发性出溶形成气泡，开发新的方法来估计挥发物在古代岩浆和脱气到大气中，探索火山爆发中的作用，微量挥发物，量化挥发物的能力运输氯，硫和矿石金属在岩浆条件下，并探讨其对岩浆系统中晶体延迟成核的影响。该研究计划以实验测量和计算机模拟为中心，并与该领域的同事合作。 更具体地说，该研究计划未来五年的目标是： 1.在实验中量化硫和卤素在熔体和含水流体之间的分配，以测量次要挥发物的溶解度及其对含水流体输送关键矿石金属（例如，Pt、Sc、Li、稀土元素等）。 2.测量实验产生的硅酸盐熔体和名义上不含挥发物的矿物（例如，长石，单斜辉石，橄榄石），以限制喷发前岩浆挥发物浓度。实验结果将与对天然矿物的测量相结合，以估计古代溢流玄武岩的挥发性释放，并将这些结果提供给大气科学家，用于模拟溢流玄武岩对陆地环境的影响。 3.通过实验室实验和X射线显微断层摄影研究，调查微量挥发物对熔体气泡出溶（成核和生长）的作用及其在引发火山爆发中的作用。这些测量结果将与计算机模型相结合，以确定不同气泡尺寸分布对岩浆泡沫渗透率和强度的影响。 4.确定挥发分在岩浆熔体过饱和中对富矿矿物结晶的作用（例如，硫化物、锂辉石、氧化铁）和伟晶岩的形成。 这项研究计划将为我们提供一个改进的图片如何挥发行为和他们在岩浆系统中发挥的作用。在五年内，我们将更好地了解岩浆中的挥发物，并将提高我们模拟岩浆演化、史前喷发的岩浆脱气、岩浆矿床的形成和火山喷发的能力。