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: 2310829
• 负责人: Susannah Dorfman
• 金额: $ 22.5万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard 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=2310829&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.

地幔中的热传输影响板块构造、火山活动和磁场。该项目测试氧化铁如何改变地幔中富含氧化铁的岩石的热传输。在这个项目中，研究人员将进行实验来生长含有氧化铁成分的地幔相关晶体。将测量这些晶体中的热流在高压和高温下的影响，结果将使他们能够研究地球大气层和地幔岩石之间的反应如何影响地球的动力学，因为它们传输热量的能力。密歇根州立大学和台湾的研究人员通过实验和共享研究生和博士后学者培训建立合作关系，将向密歇根州立大学的本科生介绍台湾的地质学和地幔硅酸盐的热导率调节地球的热性能。最近的研究调查了铁和压力引起的自旋跃迁对地幔矿物热导率的影响，然而，这些研究仅限于还原成分，如方镁石和富含亚铁的桥锰矿。金刚石砧座中的域热反射 (TDTR) 光谱，用于测定氧化铁-富铁桥石的晶格导热系数和他们将分离含铁-铁桥石中压力驱动的自旋配对转变的影响以及铝与铁铁对热传输的影响。这是密歇根州立大学、密歇根大学和学术界之间的合作。台湾的 Sinica 将结合晶体生长、极高压和温度实验以及热流测量方面的互补专业知识，以测量地幔氧化差异如何影响地幔对流。该奖项是 NSF 的法定使命通过使用基金会的智力优点和更广泛的影响审查标准进行评估，并被认为值得支持。