The Elemental and Isotopic Partitioning Behavior of Nitrogen During Magmatic Differentiation

岩浆分异过程中氮的元素和同位素分配行为

• 批准号: 2890693
• 金额: --
• 依托单位: University of St Andrews
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2890693
• 关键词: Elemental; Isotopic; Partitioning; Behavior; Nitrogen

Nitrogen is the dominant element in Earth's atmosphere at 78% by mass. It is a core element to our DNA, it is an essential nutrient for life and is a crucial ingredient to form the building blocks for life. Yet, we know little about how earth's atmosphere came to be so nitrogen rich, and how nitrogen moves between earth's reservoirs. These questions are still a topic of debate, and the answers have great implications to our understanding of Earth's elemental fluxes, evolution of our atmosphere, evolution of life on earth, and how other planets differ to our own. Due to the wide range in valency of nitrogen, nitrogen can form a variety of species (e.g. N2, nitride, nitrate, ammonium, ammonia, etc) under different geochemical conditions. Many of these nitrogen species behave very differently in silicate Earth, with different compatibilities, charges, volatility etc. Due to their wide range of traits, they can substitute for many similar ions in the crystal lattice of common minerals in the crust and mantle. Therefore, we must better constrain how nitrogen behaves in silicate earth, and what factors affect its behaviour, to understand how nitrogen occupies, and moves through, our planet.This project aims to identify the behaviour of nitrogen under different geochemical conditions: specifically, its elemental and isotopic partitioning behaviour during magmatic differentiation. A range of alkaline and subalkaline rocks from volcanic and plutonic settings will be analysed to speak to the behaviour of nitrogen atoms and isotopes under different tectonic and geochemical conditions. The samples will show a variation in P-T-X-fO2 conditions during formation and the research results should therefore be able to speak to the effect of each of these parameters on the behaviour of nitrogen. Specific findings are expected to include: the source of nitrogen in investigated igneous systems; the key controlling factors on nitrogen behaviour; the elemental and isotopic partitioning behaviour of nitrogen as igneous systems evolve, how nitrogen partitions between key silicate minerals within an evolving system, and how volcanic degassing of nitrogen is influenced by igneous differentiation.

氮是地球大气中的主要元素，质量为78％。它是我们DNA的核心元素，它是生命的必不可少的营养素，并且是构成生命基础的关键成分。然而，我们对地球大气变得如此富含氮的大气以及氮如何在地球储层之间移动。这些问题仍然是一个辩论的话题，答案对我们对地球元素通量的理解，大气的演变，地球上的生命进化以及其他行星与我们自己的不同，具有很大的影响。由于氮的价值范围很大，氮可以在不同的地球化学条件下形成多种物种（例如N2，氮化物，硝酸盐，硝酸盐，铵，氨等）。这些氮物种中的许多在硅酸盐地球上的行为有很大不同，由于其广泛的特征，它们具有不同的兼容性，电荷，波动性等。它们可以代替地壳和地幔中普通矿物质的晶体晶格中的许多类似离子。因此，我们必须更好地限制氮在硅酸盐地球中的行为，以及哪些因素影响其行为，以了解氮的占据并贯穿我们的星球。该项目旨在确定在不同的地球化学条件下氮的行为：具体而言，其元素和同位素分析在岩浆差异化过程中的元素和同位素分配。将分析来自火山和冥王星环境中的一系列碱性和亚甲碱岩石，以在不同的构造和地球化学条件下谈到氮原子和同位素的行为。样品将在形成过程中显示P-T-X-FO2条件的变化，因此，研究结果应能够说明这些参数中的每个参数对氮行为的影响。预期的具体发现包括：研究的火成岩系统中的氮来源；氮行为的关键控制因素；氮作为火成岩系统的元素和同位素分配行为，氮在不断发展的系统中如何在关键的硅酸盐矿物质之间分配以及氮的火山脱位如何受到火成点分化的影响。