Element Partitioning in Earth's Deep Magma Ocean

像月球形成撞击这样的高能巨型撞击会在地球早期历史中导致全球岩浆海洋。重金属物质会在地球深处的岩浆海洋中从熔融的硅酸盐地幔中分离出来，形成金属核。这一过程留下了独特的地幔化学特征，并确定了地核的化学组成。随着高温高压技术与分析工具相结合的发展，该团队将在实验室中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，使广泛的固体地球社区受益。研究结果将广泛传播，以推动地球化学科学的发展，并促进社会对地球科学的普遍了解。研究的目的是利用多砧压机中新开发的大型烧结金刚石立方体组件和改进的激光加热金刚石砧室样品配置，结合最先进的样品回收和分析工具，确定液态硅酸盐和金属之间的元素分配。具体项目包括：（1）确定钾在液态金属和硅酸盐之间的分配，以量化深岩浆海洋情景中对核心的放射性能量贡献;（2）确定压力、温度和成分对硅和氧分配系数的影响。这些实验将为钾、硅和氧提供新的分配数据，用于量化热量预算和隔离到核心中的轻元素的数量。这项工作将大大提高我们对地球深部过程的认识，并通过实验技术来研究地球深部内部的组成。该奖项反映了NSF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。

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.