CAREER: Elasticity and Lattice Dynamics of Iron Alloys under Earth's Core Conditions

职业：地球核心条件下铁合金的弹性和晶格动力学

• 批准号: 1555388
• 负责人: Bin Chen
• 金额: $ 57万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-15 至 2022-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1555388&HistoricalAwards=false
• 关键词: CAREER; Elasticity; Lattice; Dynamics; Iron

Residing at the center of the Earth, the core is the innermost but extremely dynamic region of our planet. Over the last two decades, geophysicists have expended tremendous effort in deciphering the compositional makeup, thermal structure, and seismic features of the Earth's core. Understanding the nature and dynamics of the core can deeply enhance our abilities in understanding the magnetic field generation process, the thermo-chemical evolution of the Earth's deep interior, and the formation of the Earth as a habitable planet. This Faculty Early Career Development (CAREER) program aims to investigate the elasticity and lattice dynamics of iron alloys as candidates for the inner core under high pressure and temperature conditions of the core, using multiscale state-of-the-art experimental facilities. The outcome of the proposed research is a new set of fundamental mineral physics data on density, sound velocities, and single-crystal elasticity of iron alloys under previously uncharted pressure-temperature regimes, essential for us to provide further constraints on the core's composition and dynamics. The experimental results are to be integrated to a comprehensive mineral physics database for the core, cultivating collaborations with sister disciplines such as seismology, geodynamics and geochemistry, and ultimately enhancing our profound understanding of nature and dynamics of the Earth's deepest interior. Furthermore, the involvement of student researchers in the proposed research and the development of a research and teaching facility for high-pressure mineral and materials science will initiate the 'pipeline' that helps influence and attract diverse student population, particularly traditionally underrepresented minorities, into Earth science and build diverse geoscience workforce.This proposal aims to systematically measure high pressure-temperature elastic and vibrational properties of candidate iron alloys for the inner core, using synchrotron-based X-ray spectroscopies combined with resistively- and laser-heated diamond anvil cell techniques, so as to address the following scientific questions: (1) How do pressure and temperature affect the elastic and vibrational properties of iron alloys under core conditions? (2) What are the alloying effects of candidate light elements on the elasticity of iron under core conditions? (3) What are the single crystal elasticities of iron alloys approaching the core conditions, for the interpretation of the inner core's seismic anisotropy and fine-scale seismic? (4) Finally, what are the likely lighter alloying components in the inner core and what would that imply for the thermochemical evolution of the core and the planet? The integrated education and outreach objective is to train a new generation of independent solid Earth geoscientists in laboratory- and synchrotron-based facilities and to offer inquiry-base learning opportunities and experience to K-16 students through the implementation of a 'Multi-Anvil Press Laboratory' (MAPLab) teaching module to geosciences curricula. The results of the project will be widely disseminated on a timely manner through national and international meetings, public lectures and outreach, and news media.

核心位于地球的中心，是我们星球最内部但极具活力的区域。在过去的二十年里，地球物理学家花费了巨大的努力来破译地球核心的成分构成，热结构和地震特征。了解地核的性质和动力学可以大大提高我们理解磁场产生过程、地球深部内部的热化学演化以及地球作为可居住行星的形成的能力。该学院早期职业发展（CAREER）计划旨在研究铁合金的弹性和晶格动力学，作为核心高压和高温条件下内核的候选材料，使用多尺度最先进的实验设施。拟议研究的结果是一组新的基本矿物物理学数据的密度，声速和铁合金的单晶弹性下以前未知的压力-温度制度，为我们提供进一步的核心的组成和动力学的约束。实验结果将被整合到一个全面的矿物物理数据库中，培养与地震学，地球动力学和地球化学等姐妹学科的合作，并最终提高我们对地球最深内部的自然和动力学的深刻理解。此外，学生研究人员参与拟议的研究，并为高压矿物和材料科学开发研究和教学设施，将启动“管道”，有助于影响和吸引不同的学生群体，特别是传统上代表性不足的少数民族，地球科学和建设多样化的地球科学队伍。这项建议的目的是系统地测量高压-利用同步加速器X射线光谱仪结合反射和激光加热金刚石对顶砧技术，研究内核候选铁合金的温度弹性和振动特性，以解决以下科学问题：（1）在堆芯条件下，压力和温度如何影响铁合金的弹性和振动性质？(2)在堆芯条件下，候选轻元素对铁的弹性有什么合金化作用？(3)为了解释内核的地震各向异性和精细尺度地震，接近内核条件的铁合金的单晶弹性是多少？(4)最后，内核中可能较轻的合金成分是什么？这对内核和行星的热化学演化意味着什么？综合教育和推广目标是在实验室和同步加速器设施中培训新一代独立的固体地球科学家，并通过在地球科学课程中实施“多砧压力实验室”（MAPLab）教学模块，为K-16学生提供基于探究的学习机会和经验。将通过国家和国际会议、公开讲座和外联活动以及新闻媒体，及时广泛传播该项目的成果。

项目成果

Carbon in the Core, in Deep Earth: Physics and Chemistry of the Lower Mantle and Core (eds H. Terasaki and R. A. Fischer)

地球深处地核中的碳：下地幔和地核的物理和化学（H. Terasaki 和 R. A. Fischer 编辑）

• 发表时间: 2016
• 期刊: Geophysical monograph
• 作者: Chen, B.;Li, J.
• 通讯作者: Li, J.

Density of Fe‐Ni‐C Liquids at High Pressures and Implications for Liquid Cores of Earth and the Moon

高压下 Fe-Ni-C 液体的密度及其对地球和月球液体核心的影响

• DOI: 10.1029/2020jb021089
• 发表时间: 2021
• 期刊: Journal of Geophysical Research: Solid Earth
• 作者: Zhu, Feng;Lai, Xiaojing;Wang, Jianwei;Amulele, George;Kono, Yoshio;Shen, Guoyin;Jing, Zhicheng;Manghnani, Murli H.;Williams, Quentin;Chen, Bin
• 通讯作者: Chen, Bin

Elastic and magnetic properties of Fe3P up to core pressures: Phosphorus in the Earth's core

• DOI: 10.1016/j.epsl.2019.115974
• 发表时间: 2020-02-01
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Lai, Xiaojing;Zhu, Feng;Chen, Bin
• 通讯作者: Chen, Bin

An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions

• DOI: 10.3791/61389
• 发表时间: 2020-06-01
• 期刊: JOVE-JOURNAL OF VISUALIZED EXPERIMENTS
• 影响因子: 1.2
• 作者: Lai, Xiaojing;Zhu, Feng;Chen, Bin
• 通讯作者: Chen, Bin

Superstoichiometric Alloying of H and Close‐Packed Fe‐Ni Metal Under High Pressures: Implications for Hydrogen Storage in Planetary Core

高压下 H 和密堆积 Fe-Ni 金属的超化学计量合金化：对行星核心储氢的影响

• DOI: 10.1029/2022gl101155
• 发表时间: 2023
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Piet, Hélène;Chizmeshya, Andrew;Chen, Bin;Chariton, Stella;Greenberg, Eran;Prakapenka, Vitali;Buseck, Peter;Shim, Sang‐Heon
• 通讯作者: Shim, Sang‐Heon