科学探索|科学家在嫦娥五号月壤中发现铁橄榄石分解成因单质金属铁( 二 ) 科学家在嫦娥五号月壤中发现

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图1. 嫦娥五号月壤铁橄榄石颗粒最表层环带的成分特征，主要由含气孔纳米金属铁（v-npFe⁰），富镁层（Mg-layer）以及富硅组分（Si）组成。
本研究结果证实了月壤中单质金属铁新的成因机制，为嫦娥五号着陆区月壤形成与演化过程的研究提供了参考依据，同时也为后续月球、小行星等返回样品分析提供了新的思路。审稿人对此工作均作出正面评价，认为该研究结果是区别于Apollo样品的一类典型微观结构，并且对于解释太阳系无大气行星体表面性质具有重要意义（Reviewer #1: This paper describes very interesting space weathering features in the rim of Fe-rich olivine returned Chang’E-5, and space weathering in such high-Fe silicates has not yet been reported on in lunar samples； Reviewer #2: This manuscript well presents important findings to interpret the Surface properties of airless bodies in the Solar System）。

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图2. 含气孔单质金属铁的电子能量损失谱（EELS）线扫描和透射电镜能谱仪（EDS）面扫描结果。
近期该项研究成果以“Nanophase Iron Particles Derived From Fayalitic Olivine Decomposition in Chang'E-5 Lunar Soil: Implications for Thermal Effects During Impacts” 为题发表在Nature Index期刊《Geophysical Research Letters》上，论文第一作者是中国科学院地球化学研究所博士研究生郭壮，通讯作者是中国科学院地球化学研究所李阳副研究员。该成果得到了中国国家航天局嫦娥五号月壤样品（CE5C0400YJFM00505）的支持以及中科院类地行星先导专项（XDB41000000）、国家自然科学基金委重点基金（41931077）、国防科工局民用航天项目（D020201）、中科院青年创新促进会（2020395）以及中科院重点部署、前沿重点（ZDBS-SSW-JSC007-10，QYZDY-SSW-DQC02）等项目的资助。
参考文献：
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【科学探索|科学家在嫦娥五号月壤中发现铁橄榄石分解成因单质金属铁】3) Anand, M., Taylor, L. A., Nazarov, M. A., et al., (2004). Space weathering on airless planetary bodies: Clues from the lunar mineral hapkeite. Proceedings of the National Academy of Sciences of the United States of America, 101, 6847–6851. https://doi.org/10.1073/pnas.0401565101
4) Li Q., Zhou Q., Liu Y., et al., (2021) Two-billion-year-old volcanism on the Moon from Chang’E-5 basalts. Nature, 600, 54-58. https://doi.org/10.1038/s41586-021-04100-2
5) Qian, Y., Xiao, L., Head, J. W., et al.，(2021). Copernican-aged (<200 Ma) impact Ejecta at the Chang'E-5 landing site: Statistical evidence from crater morphology, morphometry, and degradation models. Geophysical Research Letters, 48, e2021GL095341. https://doi.org/10.1029/2021GL095341
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