Experimental and theoretical studies of trace species in Earth materials, from mantle geodynamics to environmental applications and mineral exploration

地球材料中痕量物质的实验和理论研究，从地幔地球动力学到环境应用和矿物勘探

• 批准号: RGPIN-2018-04106
• 负责人: Pan, Yuanming
• 金额: $ 2.62万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711710
• 关键词: Experimental; theoretical; studies; trace; species

Trace species, such as substitutional or interstitial ions/molecules, vacancies and radiation-induced defects representing incipient radiation damage, in minerals and other Earth materials (e.g., melts and fluids) exert profound impacts on physical properties such as color, density, rheology, stability, electrical and thermal conductivity, magnetism, seismic velocity and many more. Trace species in Earth materials also have wide applications in solid and environmental Earth sciences from geochemical modeling to radiation dosimetry, geochronology, remediation of heavy metal/metalloid contamination, nuclear waste disposal and mineral exploration. The long-term objective of this research program is directed towards quantitative and mechanistic understanding of trace species in Earth materials, with emphasis on their geometric and electronic structures, physical properties, and applications. Scientific approaches include field-based investigations to identify specific trace species important to geological processes or directly relevant to environmental and technological applications. Laboratory experiments are designed to complement field-based research and to provide synthetic materials for spectroscopic studies that are often impossible for natural samples. Trace species in selected minerals and melts are characterized by use of multiple state-of-the-art analytical techniques, such as electron paramagnetic resonance, infrared, Raman, nuclear magnetic resonance and synchrotron X-ray absorption spectroscopy as well as periodic first-principles calculations and first-principles molecular dynamics simulations. Specific objectives for the next funding cycle are: 1) nature of radiation-induced defects in quartz and other silica with applications to mineral exploration, 2) effects of trace species in calcium carbonate minerals and carbonatitic melts from surface to lower-mantle conditions with relevance to environmental applications and mantle geodynamics, and 3) bromine systematics in rock-forming minerals and silicate melts with applications to magmatic-hydrothermal ore deposits. This research program on mechanistic understanding of trace species in Earth materials is unique in Canada and is innovative in exploring the frontiers of both experiments and theories. Also, this research program provides an excellent opportunity for highly qualified personnel (HQP) training in a multidisciplinary environment. The multidisciplinary nature of this research program is demonstrated by the attraction of high-quality HQP with diverse academic backgrounds from chemistry to engineering, geology, geophysics, materials science and physics, in-depth collaborations with chemists, materials scientists and physicists, and our publications in not only Earth science journals but also those in chemistry, materials science and physics.

矿物和其他地球材料(例如熔体和流体)中的痕量物种，如置换或间隙离子/分子、空位和辐射诱导的缺陷，代表早期的辐射损害，对颜色、密度、流变性、稳定性、导电性和导热性、磁性、地震速度等物理性质产生深刻影响。地球材料中的痕量物种在固体和环境地球科学中也有广泛的应用，从地球化学模拟到辐射剂量学、地质年代学、重金属/类金属污染的修复、核废料处理和矿产勘探。这项研究计划的长期目标是对地球材料中的痕量物种进行定量和机械的了解，重点是它们的几何和电子结构、物理性质和应用。科学方法包括实地调查，以确定对地质过程重要或与环境和技术应用直接相关的特定痕量物种。实验室实验旨在补充实地研究，并为光谱研究提供合成材料，这对于自然样品来说往往是不可能的。利用多种最先进的分析技术，如电子顺磁共振、红外、拉曼、核磁共振和同步辐射X射线吸收光谱，以及周期性的第一性原理计算和第一性原理分子动力学模拟，对选定矿物和熔体中的痕量物种进行了表征。下一个供资周期的具体目标是：1)石英和其他二氧化硅中辐射诱发缺陷的性质及其在矿产勘探中的应用；2)碳酸钙矿物和碳酸盐熔体中微量物种从地表到下地幔条件与环境和地幔地球动力学有关的影响；以及3)造岩矿物和硅酸盐熔体中溴的系统学及其在岩浆-热液矿床中的应用。这项关于对地球材料中痕量物种的机械理解的研究计划在加拿大是独一无二的，在探索实验和理论的前沿方面具有创新性。此外，该研究项目还为多学科环境下的高素质人才(HQP)培训提供了极好的机会。这一研究项目的多学科性质体现在以下几个方面：具有从化学到工程、地质学、地球物理、材料科学和物理等不同学术背景的高质量HQP的吸引力，与化学家、材料科学家和物理学家的深入合作，以及我们不仅在地球科学期刊上发表的文章，还包括化学、材料科学和物理杂志上的文章。