Renewal: Mineral Physics Studies under the Pressure-Temperature Conditions of Earth's Deep Lower Mantle

更新：地球下地幔深处压力-温度条件下的矿物物理研究

• 批准号: 1722515
• 负责人: Michael Walter
• 金额: $ 15万
• 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: 2018
• 资助国家: 美国
• 起止时间: 2018-02-15 至 2021-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1722515&HistoricalAwards=false
• 关键词: Renewal; Mineral; Physics; Studies; under

The investigators believe they have discovered a giant oxygen reservoir at the extreme pressure-temperature conditions between the Earth's deep mantle and iron core. The reservoir consists of previously unknown iron superoxides which could suddenly release its excessive oxygen. In the present project, the team will further explore the different types of iron superoxides, the conditions for the explosive oxygen release, and the consequences of oxygen eruptions. The sporadic eruptions provide a new, unified mechanism for answering questions on a list of seemingly unrelated past events that occurred during Earth's 4.6 billion years history and shaped the present living planet. Where did the oxygen in the air come from? What caused the mass extinctions that killed the dinosaurs and ushered in the mammals? What was the driving force that pushed all continents to merge into a single supercontinent, and later pulled the supercontinent apart to form individual continents? From understanding the Earth's Past and Present, we may gain insights into the Earth's Future.The investigator's recent discovery of high P-T iron superoxides, FeO2 and FeO2Hx with the pyrite-type Pa3 structure has suggested potential paradigm changes in mineral physics and geodynamics of the deep lower mantle. The team proposes to further investigate the high P-T mineral physics properties of the superoxides, including the incorporation of other major components such as MgO2, AlO2 and SiO2 into the Pa3 iron superoxide, its interactions with silicate bridgmanite and post-perovskite, its electronic and magnetic spin states, and its valence states of iron and oxygen. The team will search for other stable structural types in addition to Pa3 for firon-based superoxides with the apparent Fe oxidation state 3+, and determine their elastic wave velocities for comparison for comparison with seismic observations in the deep Earth. The team's previous research suggested the existence of a massive amount of oxygen-rich patches at the core-mantle boundary. This research will investigate the metastability of such giant oxygen reservoirs, and the consequences when the stored oxygen is released, particularly the resulting geodynamics of the super plate tectonics that may explain the origin of merging and rifting of supercontinents.

研究人员认为，他们在地球深地幔和铁核之间的极端压力温度条件下发现了一个巨大的氧气储层。 该储层由以前未知的铁氧化物组成，可能会突然释放其过量的氧气。 在本项目中，团队将进一步探索不同类型的铁超氧化物，爆炸性氧气释放的条件以及氧气喷发的后果。 零星的爆发提供了一种新的统一机制，可以在地球46亿年历史上发生的看似无关的过去事件清单上回答问题，并塑造了当前的生命星球。 空气中的氧气从何而来？ 是什么原因导致杀死恐龙并将哺乳动物引入的大规模灭绝？ 什么是推动所有大陆合并成一个超大陆的驱动力，后来将超大陆拉开以形成单个大陆？ 从了解地球的过去和现在，我们可能会深入了解地球的未来。研究人员最近发现了具有黄铁矿型PA3结构的高P-T铁超氧化物，FEO2和FEO2HX，这表明矿物质物理学和深层矿物质学的矿物质物理学和地球动力学的潜在范式变化。 该团队提议进一步研究超氧化物的高P-T矿物质物理学特性，包括将其他主要成分（例如MGO2，ALO2和SIO2）掺入PA3铁超氧化物中，并与硅酸盐Bridgmanite和玻璃体后晶矿的相互作用，其电子和磁性态及其价值状态以及其价值状态，以及其Valence in Iron和oxygen。除了PA3外，该团队还将搜索其他稳定的结构类型，以寻找具有明显的Fe氧化状态3+的基于Firon的超氧化物，并确定其弹性波速度，以进行比较，以与深地球中的地震观测值进行比较。 该团队先前的研究表明，在核心掩体边界上存在大量富氧斑块。这项研究将研究此类巨型氧气储存剂的亚稳定性，以及释放储存的氧气时的后果，特别是超级板块构造的地球动力学，这可能解释了超前的合并和裂解的起源。

项目成果

Altered chemistry of oxygen and iron under deep Earth conditions

• DOI: 10.1038/s41467-018-08071-3
• 发表时间: 2019-01-11
• 期刊: NATURE COMMUNICATIONS
• 影响因子: 16.6
• 作者: Liu, Jin;Hu, Qingyang;Mao, Wendy L.
• 通讯作者: Mao, Wendy L.

Solids, liquids, and gases under high pressure

• DOI: 10.1103/revmodphys.90.015007
• 发表时间: 2018-03-20
• 期刊: REVIEWS OF MODERN PHYSICS
• 影响因子: 44.1
• 作者: Mao, Ho-Kwang;Chen, Xiao-Jia;Wang, Lin
• 通讯作者: Wang, Lin

Discovery of a hexagonal ultradense hydrous phase in (Fe,Al)OOH

• DOI: 10.1073/pnas.1720510115
• 发表时间: 2018-03
• 期刊: Proceedings of the National Academy of Sciences
• 作者: Li Zhang;Hongsheng Yuan;Y. Meng;H. Mao

Diamond anvil cell behavior up to 4 Mbar

• DOI: 10.1073/pnas.1721425115
• 发表时间: 2018-02-20
• 期刊: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• 影响因子: 11.1
• 作者: Li, Bing;Ji, Cheng;Mao, Ho-kwang
• 通讯作者: Mao, Ho-kwang

New high-pressure tetragonal polymorphs of SrTiO 3 —molecular orbital and Raman band change under pressure

新型高压四方多晶型SrTiO 3 – 分子轨道和拉曼带在压力下的变化

• DOI: 10.1088/1361-648x/aabef3
• 发表时间: 2018
• 期刊: Journal of Physics: Condensed Matter
• 作者: Yamanaka, Takamitsu;Ahart, Muhtar;Mao, Ho-kwang;Yan, Hao
• 通讯作者: Yan, Hao