Water in the Earth's lower mantle

地球下地幔中的水

• 批准号: 2242946
• 负责人: Jie Deng
• 金额: $ 44.27万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2242946&HistoricalAwards=false
• 关键词: Water; Earth; lower; mantle

The most vital component of the Earth is water. It is not only the source of life, but also the key ingredient controlling a wide range of solid earth processes, such as the operation of plate tectonics, the formation of volcanoes, and the emergence of continents. Plate tectonics and volcanic eruptions lead to the active exchange of surface water and interior water, regulating the variation of ocean volumes and continent areas throughout the Earth’s history. Despite its importance, in present-day the Earth’s surface water accounts for only 0.02 percent of the planet’s total mass. Most of the Earth’s water is instead thought to be present in the Earth’s deep interior, but the exact amount of water stored in the Earth’s interior remains largely unknown. This proposal will rigorously study the water solubility in bridgmanite, the most abundant material of the deep mantle. This will be accomplished by using large-scale computer simulations of bridgmanite and fluid in coexistence, using the latest innovations in machine learning. The calculations will be referenced to results derived from high-precision calculations based in quantum mechanics. This work will support the training of graduate students in cutting-edge computational techniques using high-performance computing centers. Water solubility in the mantle is a fundamental material property that quantifies the maximum amount of water that can be hosted within the Earth. Large-scale two-phase simulations of bridgmanite and fluid coexistence driven by machine learning potentials of ab initio quality will be carried out to rigorously study the water solubility in bridgmanite. These simulations will reveal: 1) the solubility of water in bridgmanite and the effects of Fe and Al across the entire lower mantle; 2) the hydrogen incorporation mechanisms as a function of pressures, temperatures, and bulk chemistry; 3) the bridgmanite-water (pseudo)-binary phase diagrams; and 4) the evolutionary history of the water storage capacity of the lower mantle over the past 4.5 billion years. This project is co-funded by the Directorate for Geosciences to support AI/ML advancement in the geosciences.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.

地球上最重要的组成部分是水。它不仅是生命的来源，而且是控制广泛的固体过程的关键要素，例如板块构造的运行，火山的形成和大陆的出现。板块构造和火山喷发导致地表水和室内水的积极交换，从而减轻了地球历史上海量和大陆区域的变化。尽管它很重要，但在当今地球的地表水仅占地球总质量的0.02％。相反，地球上大部分水都存在于地球深内部的内部，但是地球内部存储的确切水量仍然很少。该提案将严格研究Bridgemanite的水溶性，Bridgemanite是深层地幔中最丰富的材料。这将通过使用机器学习中的最新创新来使用BridgeManite和流体的大规模计算机模拟来实现。该计算将参考基于量子力学的高精度计算得出的结果。这项工作将支持研究生使用高性能计算中心对尖端计算技术进行培训。地幔中的水溶性是一种基本材料特性，可量化可在地球内托管的最大水量。将对从头开始质量的机器学习潜力驱动的Bridgemanite和流体共存的大规模两相模拟将进行严格研究Bridgemanite中的水溶性。这些模拟将揭示：1）水在Bridgemanite中的溶解度以及Fe和Al在整个下层地幔中的影响； 2）氢感染机制是压力，温度和散装化学的函数； 3）Bridgemanite-Water（伪） - 二元相图； 4）在过去的45亿年中，低地幔的储能能力的进化历史。该项目由地球科学局共同资助，以支持地球科学中的AI/ML进步。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，认为通过评估被认为是宝贵的支持。