CSEDI: Experimental Constraints on Dynamic Processes in Earth's Core

CSEDI：地核动态过程的实验约束

• 批准号: 0215624
• 负责人: James Van Orman
• 金额: $ 16.25万
• 依托单位: Carnegie Institution of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0215624&HistoricalAwards=false
• 关键词: CSEDI; Experimental; Constraints; Dynamic; Processes

The transport properties of iron alloys are central to the understanding ofdynamic processes in the Earth's core, including convective motions in theouter core (which drive the geodynamo) and solid-state deformation in theinner core, which may be responsible for the observed seismic anisotropy.To better understand these processes the PIs propose to conductexperimental studies of diffusional transport in iron at high pressure (upto 27 GPa). Rates of diffusion of several chemical species (Fe, S, O, andOs) will be measured in both liquid iron and in high-pressure solid phases(fcc and hcp). The experiments will extend to significantly higherpressures than have been examined previously and will provide a more securebasis for extrapolating diffusion rates and diffusion-related properties tothe conditions of the core. The results will lead to a betterunderstanding of inner core rheology and mechanisms for producinganisotropic textures; the viscosity and role of compositional convection inthe outer core; and the spatial distribution of osmium isotopes and otherchemical species within the core.

铁合金的运输特性对于地球核心的理解是核心，包括对对流核心的对流运动（驱动着地球诺（Geodynamo）的对流运动）和Inner核心中的固态变形，这可能导致观察到的地震性各向异性各向异性型，以更好地理解这些过程的PIS提出的较高的压力（在越来越高的越来越多的越来越高）中，在越来越高的越来越多的越来越高的越来越多。 将在液态铁和高压固相（FCC和HCP）中测量几种化学物种（Fe，S，O，Andos）的扩散率。 实验将扩展到比以前检查的明显更高的压力，并为推断扩散速率和与扩散相关的特性提供了更安全的基础。 结果将导致对内部核心流变学和产生植物质地的机制的更好理解。粘度和组成对流在外部芯中的作用；以及核心内的osmium同位素和其他化学物种的空间分布。