Collaborative Research: Effects of ferric iron on heat transport in Earth's mantle

合作研究：三价铁对地幔热传输的影响

• 批准号: 2310830
• 负责人: Jie Li
• 金额: $ 17.49万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 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: 2023-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2310830&HistoricalAwards=false
• 关键词: Collaborative; Research; Effects; ferric; iron

Heat transport in Earth’s mantle affects plate tectonics, volcanism, and the magnetic field. How materials carry heat varies with depth, temperature, and composition. This project tests how oxidized iron changes heat transport in the mantle. Oxidized iron-rich rock in tectonic plates subducts to the mantle and may be enriched at the base of the mantle. In this project, researchers will conduct experiments to grow mantle-relevant crystals with compositions including oxidized iron. They will measure heat flow in these crystals at high pressures and temperatures. The results will allow them to examine how reactions between Earth's atmosphere and mantle rock affect the Earth’s dynamics as a consequence of their ability to transport heat. This project will enable a new technique at Michigan State and establish collaboration between researchers in Michigan and Taiwan through experiments and shared graduate student and postdoctoral scholar training. Michigan undergraduate students will be introduced to geology of Taiwan and thermal properties of Earth materials. Thermal conductivity of mantle silicates modulates the Earth’s dynamics. Recent studies have investigated the effects of iron and pressure-induced spin transitions on thermal conductivity in mantle minerals. However, these studies have been limited to reduced compositions such as ferropericlase and ferrous-iron-rich bridgmanite. The researchers will use ultrafast time-domain thermo-reflectance (TDTR) spectroscopy in diamond anvil cells to determine the lattice thermal conductivity of oxidized ferric-iron-rich bridgmanite and post-perovskite. They will isolate the effects of the pressure-driven spin pairing transition in ferric-iron-bearing bridgmanite and effects of aluminum versus ferric iron on heat transport. This collaboration between Michigan State University, the University of Michigan, and the Academia Sinica in Taiwan will combine complementary expertise in crystal growth, extreme high pressure and temperature experiments, and heat flow measurement to measure how differences in oxidation in the mantle impact mantle convection.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.

地球上的热运输会影响板块构造，火山和磁场。材料如何随着深度，温度和成分而变化。该项目测试了氧化铁如何改变地幔中的热传输。构造板中的富含铁岩石岩石俯冲到地幔，可能会富集在地幔的底部。在这个项目中，研究人员将进行实验，以种植与氧化铁在内的成分相关的晶体。他们将在高压和温度下测量这些晶体中的热流。结果将使他们能够检查地球大气与地幔岩之间的反应如何由于运输热量的能力而影响地球动态。该项目将通过实验和共享研究生和博士后科学培训来建立密歇根州立大学的新技术，并在密歇根州和台湾建立研究人员之间的合作。密歇根大学的本科生将被介绍台湾地质和地球材料的热性质。地幔硅酮的导热率调节地球的动力学。最近的研究研究了铁和压力诱导的自旋跃迁对地幔矿物导热率的影响。然而，这些研究仅限于减少组合物，例如铁磷酸酯和铁铁矿富含bridgemanite。研究人员将使用钻石砧细胞中的超快时间域热反射（TDTR）光谱来确定氧化富铁的富含铁的Bridgemanite和perovskite的晶格导热率。他们将隔离铁铁型bridgemanite中压力驱动的自旋跃迁的影响，以及铝与铁铁对热传输的影响。密歇根州立大学，密歇根大学和台湾西尼卡学术界之间的这种合作将结合晶体增长，极端高压和温度实验的完整专业知识，并进行热流量测量，以衡量地幔氧化的氧化差异如何通过评估NSF的法定责任和宽广的支持。