An integral approach to reveal the identity of light elements in the Earth's core

揭示地核轻元素身份的整体方法

基本信息

批准号：
1214990
负责人：
Yingwei Fei
金额：
$ 40.39万
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：
2012
资助国家：
美国
起止时间：
2012-07-01 至 2016-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1214990&HistoricalAwards=false
关键词：
integral approach reveal identity light

项目摘要

The Earth has an iron-dominant core that consists of a liquid outer core and a solid inner core at the center. The Earth's core is the engine of the planet, generating global magnetic field and driving large-scale plate motions on the surface through mantle convection. A better understanding of its chemical composition will help us to understand how the engine works. Current knowledge of the core implies that incorporation of light elements (such as sulfur, oxygen, silicon) in the iron core is necessary to explain the observed density and velocities of the core, but there is considerable controversy over the precise identity of the light alloying elements in the core because it is experimentally challenging to precisely measure the density and sound velocity of the iron alloys under core conditions.In this study, I am outlining a new approach to narrow down the identity of the light elements in the core by combining dynamic and static compression experiments. The proposed experiments will yield new density and velocity data obtained by shock compression and static compression in the high-temperature diamond-anvil cell. Specifically, I propose four types of experiments, (1) shock compression to obtain densities of Fe-Si alloys, (2) in-situ x-ray diffraction measurements in high-temperature diamond-anvil cell to obtain P-V-T data, (3) measurements of the sound velocities of the alloys by shockwave experiments, and (4) measurements of the compressional-wave velocity of alloys in the high-temperature diamond-anvil cell by inelastic x-ray scattering technique. This is our first attempt to integrate results from dynamic and static compression experiments on the same samples, which allows us to obtain complementary data over a wide P-T range and to establish self-consistent database from two independent high-pressure experiments. The new data on Fe-Si alloys will be integrated into our existing data to make comprehensive models of the core.

地球具有一个铁芯芯，该芯由液体外芯和中心的固体内核组成。地球的核心是行星的发动机，通过地幔对流产生了全球磁场并在表面上驱动大型板块运动。更好地了解其化学成分将有助于我们了解发动机的工作原理。 Current knowledge of the core implies that incorporation of light elements (such as sulfur, oxygen, silicon) in the iron core is necessary to explain the observed density and velocities of the core, but there is considerable controversy over the precise identity of the light alloying elements in the core because it is experimentally challenging to precisely measure the density and sound velocity of the iron alloys under core conditions.In this study, I am outlining a通过组合动态和静态压缩实验，可以缩小核心中光元素身份的新方法。所提出的实验将产生通过高温钻石 - 洋维出细胞中的休克压缩和静态压缩获得的新密度和速度数据。具体而言，我提出了四种类型的实验，（1）休克压缩以获得Fe-SI合金的密度，（2）高温钻石型电池中的原子X射线衍射测量值，以获得P-V-T数据，（3）Alloys在Shockwave velys sound veliestions sound veliestions youshwave veliestions and（3）的测量值（3）及（4）的测量值（4）。通过非弹性X射线散射技术的高温钻石 - 钻石细胞。这是我们第一次尝试在相同样品上整合动态和静态压缩实验的结果，这使我们能够在宽P-T范围内获得互补数据，并从两个独立的高压实验中建立自洽数据库。有关FE-SI合金的新数据将集成到我们的现有数据中，以制定核心的全面模型。