Superdeep Diamonds from the Transition Zone and Lower Mantle

来自过渡带和下地幔的超深钻石

• 批准号: 1853521
• 负责人: Steven Jacobsen
• 金额: $ 43.52万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-02-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1853521&HistoricalAwards=false
• 关键词: Superdeep; Diamonds; Transition; Zone; Lower

Diamond is a remarkable material for its ultimate physical properties and technological applications. Natural diamonds also reveal physical and chemical processes in the Earth's deep mantle from where there are few direct samples. Mineral inclusions in diamond reflect reactions involving high pressure, high temperature, fluids, melts, and dynamic interactions between the Earth's surface and interior. This project will support technological development to investigate tiny mineral inclusions in diamonds. A new suite of more than 150 diamonds of deep origin, which formed at depths greater than 410 km in the transition zone and the lower mantle, will be investigated. 3D imaging, diffraction, and spectroscopy of the hosted inclusions will be carried out at national X-ray and infrared facilities. Up to a thousand micro-mineral inclusions will be identified and characterized by fast, high-throughput methods. Results of this research will improve our understanding of the mineral diversity in the Earth's interior, with special focus on water and hydrous phases. The goal is to reveal the mechanisms by which water recycles between the crust and mantle through plate tectonics, a process at the origin of numerous natural hazards. This project will foster collaboration with two local high-school teachers to introduce a geophysics curriculum to their physics courses. It will also promote the training of several graduate students for future careers in academia, federal agencies, industry, and the national laboratories. The high strength and stability of diamond make it a perfect vessel for transporting minerals and geochemical information from the deep mantle to the surface as part of the crust-mantle carbon cycle. This study will examine a new suite of superdeep diamonds from Juina, Brazil, which host mineral inclusions from the transition zone and lower mantle. One of the major challenges pertains to determining the depth origin of the diamonds which often lack a complete suite of mineral inclusions to pinpoint their formation conditions. Up to a thousand inclusions will be analyzed potentially promoting the discovery of new mineral phases and providing information about how deeply water is transported into the mantle. New micro-analysis techniques will increase the rate and decrease the size of inclusions that can be studied, thus broadening the database of mantle mineralogy. Spectroscopic methods will probe various types of atomic-scale defects in diamonds as tracers for their depth of origin. Separately, the sound velocity of diamond will be measured at high pressure in all directions of the structure to determine diamond elastic properties. This will improve the geophysical modeling of seismic wave velocity in the deep, crustal roots below continents. Other experiments will examine the decompression behavior of hydrous minerals at upper mantle temperatures to elucidate diamond ascent pathways. Ultimately this research will improve and potentially modify the textbook picture of the structure and dynamics of Earth's interior.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.

金刚石是一种卓越的材料，其最终的物理性质和技术应用。天然钻石还揭示了地球深部地幔的物理和化学过程，那里几乎没有直接的样本。钻石中的矿物包裹体反映了高压、高温、流体、熔体以及地球表面和内部之间的动态相互作用。该项目将支持研究钻石中微小矿物包裹体的技术发展。一套新的150多颗深源钻石将被研究，这些钻石形成于过渡带和下地幔深度超过410公里的地方。包裹体的三维成像、衍射和光谱将在国家x射线和红外设备上进行。多达一千种微量矿物包裹体将被识别和表征快速，高通量的方法。这项研究的结果将提高我们对地球内部矿物多样性的理解，特别关注水和含水相。其目的是揭示水通过板块构造在地壳和地幔之间循环的机制，这一过程是许多自然灾害的起源。该项目将促进与两名当地高中教师的合作，在他们的物理课程中引入地球物理课程。它还将促进对未来在学术界、联邦机构、工业和国家实验室工作的研究生的培训。钻石的高强度和稳定性使其成为将矿物和地球化学信息从地幔深处运送到地表的完美容器，作为地壳-地幔碳循环的一部分。这项研究将研究来自巴西Juina的一套新的超深钻石，其中包含来自过渡带和下地幔的矿物包裹体。其中一个主要的挑战是确定钻石的深度来源，这些钻石往往缺乏一整套矿物包裹体来确定它们的形成条件。多达一千个包裹体将被分析，有可能促进新的矿物相的发现，并提供有关水被输送到地幔的深度的信息。新的微观分析技术将增加包裹体研究的速度，减少包裹体的大小，从而扩大地幔矿物学的数据库。光谱学方法将探测钻石中各种类型的原子级缺陷，作为它们起源深度的示踪剂。另外，将在结构的各个方向测量高压下金刚石的声速，以确定金刚石的弹性性能。这将改进大陆下方地壳深处地震波速度的地球物理模拟。其他实验将研究含水矿物在上地幔温度下的减压行为，以阐明钻石上升的途径。最终，这项研究将改进并有可能修改教科书上关于地球内部结构和动力学的描述。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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

High-pressure phase transitions of clinoenstatite

• DOI: 10.2138/am-2019-6740
• 发表时间: 2019-05
• 期刊: American Mineralogist
• 影响因子: 3.1
• 作者: J. Lazarz;P. Dera;Y. Hu;Y. Meng;C. Bina;S. Jacobsen

Raman spectroscopy study of C-O-H-N speciation in reduced basaltic glasses: Implications for reduced planetary mantles

• DOI: 10.1016/j.gca.2019.08.029
• 发表时间: 2019-11-15
• 期刊: GEOCHIMICA ET COSMOCHIMICA ACTA
• 影响因子: 5
• 作者: Dalou, Celia;Hirschmann, Marc M.;Le Losq, Charles
• 通讯作者: Le Losq, Charles

Ringwoodite and zirconia inclusions indicate downward travel of super-deep diamonds

尖晶橄榄石和氧化锆内含物表明超深钻石的向下移动

• DOI: 10.1130/g50111.1
• 发表时间: 2022
• 期刊: Geology
• 影响因子: 5.8
• 作者: Lorenzon, Sofia;Novella, Davide;Nimis, Paolo;Jacobsen, Steven D.;Thomassot, Emilie;Pamato, Martha G.;Prosperi, Loredana;Lorenzetti, Alessandra;Alvaro, Matteo;Brenker, Frank
• 通讯作者: Brenker, Frank

Goldschmidtite, (K,REE,Sr)(Nb,Cr)O3: A new perovskite supergroup mineral found in diamond from Koffiefontein, South Africa

Goldschmidtite，(K,REE,Sr)(Nb,Cr)O3：在产自南非 Koffiefontein 的钻石中发现的一种新的钙钛矿超群矿物

• DOI: 10.2138/am-2019-6937
• 发表时间: 2019
• 期刊: American Mineralogist
• 影响因子: 3.1
• 作者: Meyer, Nicole A.;Wenz, Michelle D.;Walsh, James P.S.;Jacobsen, Steven D.;Locock, Andrew J.;Harris, Jeffrey W.
• 通讯作者: Harris, Jeffrey W.

Extreme redox variations in a superdeep diamond from a subducted slab

俯冲板片中超深钻石的极端氧化还原变化

• DOI: 10.1038/s41586-022-05392-8
• 发表时间: 2023
• 期刊: Nature
• 影响因子: 64.8
• 作者: Nestola, Fabrizio;Regier, Margo E.;Luth, Robert W.;Pearson, D. Graham;Stachel, Thomas;McCammon, Catherine;Wenz, Michelle D.;Jacobsen, Steven D.;Anzolini, Chiara;Bindi, Luca
• 通讯作者: Bindi, Luca