Experimental constraints on the behaviour of highly siderophile elements during planetary differentiation

行星分化过程中高亲铁元素行为的实验限制

• 批准号: 194228-2011
• 负责人: Brenan, James
• 金额: $ 2.44万
• 依托单位: Dalhousie 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=593691
• 关键词: Experimental; constraints; behaviour; highly; siderophile

The highly siderophile, or iron-loving, elements (HSE) include the more familiar precious metals (platinum, palladium, rhodium and gold) as well as exotic varieties (rhenium, osmium, ruthenium and iridium). They are all useful to society, owing to exceptional thermal, surface and electronic properties. The HSE are also of value to geologists, as they are unique in their tendency to avoid oxygen, and bond to sulfur, as well as other "sulfur-like" elements, and iron. The HSE are therefore sensitive to the processes by which planets separate into a metallic core, mantle and crust. My research program involves laboratory simulation of these processes, with a specific focus on determining how the HSE get concentrated above normal background levels; be it by iron metal, other minerals, or unusual iron-sulfur (sulfide) melts. A major focus of the planned research will be to assess the efficiency of HSE extraction from magma by sulfide melt, and by compounds of the "sulfur-like" metals arsenic, bismuth, tellurium and selenium. This information helps us to understand how the HSE become concentrated by these elements in crustal mineral deposits. Knowledge of the sulfide scavenging capacity also makes it easier to inventory the HSE content of other planets from measurements of their surface lavas, whose sulfide has been removed at depth. In addition, we will determine the origin of some of the unusual behaviours of platinum, such as why it is so abundant in the Earth's mantle (when it should all be in the core) and why some magmas contain far more platinum than expected. We also plan to branch out into an emerging research area which deals with subtle variations in the composition of iron itself, and simulate the processes by which this may occur. In sum, this work seeks to provide the essential information for using the HSE to understand how planets form and evolve. Information gained from this research is also of value to the exploration and mining industry, as it provides information on how these elements may be concentrated to economic levels, and in what mineral forms they may occur.

高度铁的或爱铁的元素（HSE）包括更熟悉的贵金属（铂，钯，阳极铬和黄金）以及异国情调（Rhenium，Osmium，osmium，ruthenium和Iridium）。由于出色的热，表面和电子特性，它们都对社会有用。 HSE对地质学家也很有价值，因为它们在避免氧气，与硫的结合以及其他“硫样”元素以及铁和铁中是独一无二的。因此，HSE对行星分离为金属芯，地幔和地壳的过程敏感。我的研究计划涉及对这些过程的实验室仿真，具体的重点是确定HSE如何集中到正常背景水平；无论是通过铁金属，其他矿物质还是不寻常的铁硫（硫化物）融化。计划研究的重点是评估硫化物熔体从岩浆中提取HSE的效率，并通过“硫酸”金属砷，二晶型，滴答以及滴滴以及硒的化合物。这些信息有助于我们了解HSE如何通过这些元素集中在地壳矿藏中。了解硫化物清除能力的知识也使从其表面熔岩的测量值中清单其他行星的HSE含量变得更加容易，其硫化物已被深入去除。此外，我们还将确定铂金的某些异常行为的起源，例如为什么它在地球的地幔中如此丰富（当它都应该在核心中）以及为什么某些岩浆包含的铂金比预期的要多得多。我们还计划分支到一个新兴的研究领域，该研究领域涉及铁本身组成的细微变化，并模拟可能发生的过程。总而言之，这项工作旨在提供使用HSE了解行星形成和发展的基本信息。从这项研究中获得的信息也对勘探和采矿业具有价值，因为它提供了有关如何集中于经济水平以及可能发生的矿物形式的信息。