Element Partitioning in Earth's Deep Magma Ocean

像月球形成撞击这样的能量巨大的撞击将在早期历史上导致地球上的全球岩浆海洋。重金属物质将从地球深部岩浆海洋中熔融的硅酸盐地幔中分离出来，形成金属核心。这一过程留下了明显的地幔化学特征，并定义了核心化学成分。随着高温高压技术的发展和分析工具的结合，该团队将在实验室模拟深部岩浆海洋的条件，并确定金属-硅酸盐分离过程中元素的分布。该项目将产生前所未有的高质量金属硅酸盐元素分配数据，这些数据对于了解我们星球的化学和演化是必要的，并为尖端研究开辟新的前沿。该计划为跨学科研究领域的年轻科学家提供培训，并开发新的实验技术，将使广泛的固体地球社区受益。研究结果将广泛传播，以促进地球化学科学，并促进社会对地球科学的普遍了解。研究的目的是通过使用新开发的大型烧结钻石立方体组件在多砧压机上确定元素在液体硅酸盐和金属之间的分配，并结合最先进的样品回收和分析工具来改进激光加热钻石砧座样品结构。具体项目包括(1)确定钾在液态金属和硅酸盐之间的分配，以量化在深部岩浆海洋情景中对岩心的放射性能量贡献，以及(2)确定压力、温度和成分对硅和氧分配系数的影响。这些实验将提供钾、硅和氧的新分配数据，用于量化热量平衡和隔离到核心中的轻元素的量。这项拟议的工作将极大地提高我们对地球深部过程和实验技术的了解，以调查地球深部内部的组成。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。

Energetic giant impacts such as the Moon-forming impact would lead to a global magma ocean on Earth in its early history. The heavy metallic materials would separate from the molten silicate mantle in the Earth’s deep magma ocean to form the metallic core. The process leaves a distinct mantle chemical signature and defines the core chemical composition. With development of high-temperature and high-pressure techniques combined with analytical tools, the team will simulate the conditions of the deep magma ocean in the laboratory and determine the distribution of elements during the metal-silicate separation. The project will produce unprecedented high-quality metal-silicate element partitioning data that are necessary for understanding the chemistry and evolution of our planet and lead to new frontiers for cutting-edge research. The program provides training for young scientists in interdisciplinary research areas and develops new experimental techniques that will benefit a broad Solid Earth community. The results will be disseminated broadly to advance science in geochemistry and promote general understanding of Earth science in society.The research is aimed at determining the element partitioning between liquid silicate and metal by using the newly developed large sintered-diamond cube assembly in the multi-anvil press and improved laser-heated diamond-anvil-cell sample configuration combined with state-of-the-art sample recovery and analytical tools. Specific projects include (1) determining potassium partitioning between liquid metal and silicate to quantify the radioactive energy contribution to the core in the deep magma ocean scenario, and (2) establishing the effect of pressure, temperature, and composition on the silicon and oxygen partition coefficients. The experiments will provide new partitioning data for potassium, silicon, and oxygen to be used to quantify the heat budget and the amounts of light elements sequestered into the core. The proposed work will significantly advance our knowledge of Earth’s deep processes and experimental techniques to investigate the composition of the Earth’s deep 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.