Fe同位素已被广泛用来制约高温地质过程中氧化还原状态的变化。Fe在地幔中以Fe2+和Fe3+的形式存在，因此Fe3+-Fe2+间的同位素平衡分馏系数(αFe3+-Fe2+)是理解Fe同位素数据的钥匙。虽然分馏系数至关重要，但对熔体中αFe3+-Fe2+的研究还非常缺乏。目前通过穆斯堡尔谱和核共振非弹性X射线散射（NRIXS）均可以计算矿物中Fe3+-Fe2+间的同位素平衡分馏系数，但结果显示通过两种计算方法得到的α(Fe3+(赤铁矿）-Fe2+(橄榄岩）)并不一致，约相差一倍。通过NRIXS也可以计算出熔体中α(Fe3+-Fe2+)≈1.0002。但这个结果无法解释地球玄武岩与地幔橄榄岩、陨石以及火星、灶神星玄武岩之间的差异。本项目拟结合实验岩石学和Fe同位素地球化学，测定硅酸盐熔体中α(Fe3+-Fe2+)。研究结果将为认识地幔熔融和岩浆演化过程中Fe同位素的分馏提供重要制约。

Fe isotope can be used to help us understand redox process in high temperature geological process. As iron exists as Fe2+ and Fe3+ in mantle, to understand Fe isotope behavior in mantle evolution, it is necessary knowing equilibrium fractionation factor (α) between Fe2+ and Fe3+. Although α is the key factor, equilibrium Fe isotope fractionation factors of Fe2+ and Fe3+ is still limited. So far, both Mössbauer spectroscopy and nuclear resonant inelastic X-ray scattering (NRIXS) can calculate α Fe3+-Fe2+ in minerals, but the results of α (Fe3+(Hematite)-Fe2+(Olivine)) show inconsistent between those two methods, about a double difference. Using parameters from NRIXS also have calculated that α(Fe3+-Fe2+) in silicate melt is 1.0002. But this result can not explain the Fe isotope difference between Earth basalt and peridotite, Martian and Vesta basalt and meteriotes. This project plans to measure equilibrium isotope fractionation factors between Fe2+ and Fe3+ in silicate melts combining experimental petrology and geochemistry methods. Furthermore, the results will provide new constrains on Fe isotope behavior in mantle partial melting and magma evolution.