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Shock Wave Studies of Liquids in Earth's Core and Mantle

地核和地幔液体的冲击波研究

基本信息

批准号：
1725349
负责人：
Paul Asimow
金额：
$ 75万
依托单位：
California Institute of Technology
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-09-15 至 2022-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1725349&HistoricalAwards=false
关键词：
Shock Wave Studies Liquids Earth

项目摘要

This award will support experimental shock wave measurements of molten rocks and metals at the pressure-temperature conditions of the deep Earth. Shock wave experiments use controlled high-speed collisions to generate high pressure and temperature for a short time, allowing unique measurements of the response of Earth materials to damage, high-speed deformation, and conditions like those in the lower mantle and core of the Earth. These data are needed to support next-generation models of lower mantle structure, the deep carbon cycle, evolution of an early terrestrial magma ocean, and the composition of the Earth's core. Molten materials are central to the understanding of planetary evolution and structure, but our understanding of them lags our understanding of solids because liquids are more complex and more difficult to study. Data from these shock wave experiments is often the only experimental data available at extreme pressure for validation of atomistic models of liquid structure and dynamics. This work leverages collaboration with Lawrence Livermore National Laboratory to exploit the expertise in the Department of Energy's shock physics group for geophysical problems and, in turn, the measurements made and methods developed in this work will have wide impact not only in experimental geophysics but also in condensed matter physics and the broader shock compression community. The project includes training of young scientists and outreach through television specials.The project incorporates technical advances that enable new experiments, more extreme conditions, higher precision results, and faster turn-around time. Advances in shock temperature measurement technique, reducing uncertainty from ~500 K to ~30 K, will be used to look at temperatures of shocked silicate liquids. The one experimental constraint on the heat capacity of a silicate liquid (pure SiO2) at high compression shows great complexity; measuring shock temperature in liquid defines this heat capacity and completes the description of the equation of state. Experiments that measure shock temperature can also be configured to measure the sound speed in the shocked liquid state, which defines high-order constraints on the equation of state and allows a key test of the Mie-Gruneisen formulation for silicate liquids. Measurement of sound speeds and densities of liquid Fe alloys along actual outer core adiabats will use a combination of shock-and-release and shock-and-ramp loading paths to bring molten Fe and Fe-alloy samples to the outer core isentrope without the need for pre-heating or extrapolation. Isentropic experiments will make the well-defined observed gradient in sound speed with depth in the outer core a new constraint on its composition.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项将支持在地球深处的压力-温度条件下对熔融岩石和金属进行冲击波实验测量。冲击波实验使用受控的高速碰撞在短时间内产生高压和温度，从而可以独特地测量地球材料对损伤、高速变形以及类似于地幔和地核的条件的反应。需要这些数据来支持下一代地幔结构、深层碳循环、早期陆地岩浆海洋的演化和地核组成的下一代模型。熔融物质是理解行星演化和结构的核心，但我们对它们的理解落后于我们对固体的理解，因为液体更复杂，更难研究。这些冲击波实验的数据往往是在极端压力下验证液体结构和动力学原子模型的唯一实验数据。这项工作利用与劳伦斯利弗莫尔国家实验室的合作，利用能源部冲击物理小组在地球物理问题上的专业知识，反过来，这项工作中所做的测量和开发的方法不仅将在实验地球物理中产生广泛的影响，而且将在凝聚态物理和更广泛的冲击压缩社区中产生广泛的影响。该项目包括对年轻科学家的培训和通过电视专题节目进行推广。该项目结合了技术进步，使新的实验、更极端的条件、更高的精度结果和更快的周转时间成为可能。冲击温度测量技术的进步，将不确定度从~500K降低到~30K，将用于观察冲击硅酸盐液体的温度。对硅酸盐液体(纯SiO_2)在高压缩下的热容的一个实验约束显示出极大的复杂性；测量液体中的冲击温度定义了这个热容，并完成了状态方程的描述。测量冲击温度的实验也可以被配置为测量冲击液体状态下的声速，这定义了对状态方程的高阶约束，并允许对硅酸盐液体的Mie-Gruneisen公式进行关键测试。测量沿实际外核绝热的液态铁合金的声速和密度将使用冲击释放和冲击斜坡加载路径相结合的方式，将熔融的铁和铁合金样品带到外核等熵，而不需要预热或外推。等熵实验将使声速随外核深度的明确观测梯度成为其组成的新限制。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Shock experiments on basalt—Ferric sulfate mixes and their possible relevance to the sulfide bleb clusters in large impact melts in shergottites

玄武岩与硫酸铁混合物的冲击实验及其与六角岩中大冲击熔体中硫化物气泡簇的可能相关性

DOI：
10.1111/maps.13770
发表时间：
2021
期刊：
Meteoritics & Planetary Science
影响因子：
2.2
作者：
Rao, M. N.;Nyquist, L. E.;Asimow, P. D.;Ross, D. K.;Sutton, S. R.;See, T. H.;Shih, C. Y.;Garrison, D. H.;Wentworth, S. J.;Park, J.
通讯作者：
Park, J.

Accidental synthesis of a previously unknown quasicrystal in the first atomic bomb test

DOI：
10.1073/pnas.2101350118
发表时间：
2021-06-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
影响因子：
11.1
作者：
Bindi, Luca;Kolb, William;Steinhardt, Paul J.
通讯作者：
Steinhardt, Paul J.

Shock synthesis of Al-Fe-Cr-Cu-Ni icosahedral quasicrystal

Al-Fe-Cr-Cu-Ni二十面体准晶的冲击合成