Cao Zhi, Guo Zhuang, Li Chen, Zhao Sizhe, Li Yang, He Qi, Wen Yuanyun, Xiao Zhiyong, Li Xiongyao, Xiao Long, Li Lifang, Wang Junhu, Liu Jianzhong
Center for Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences, 550081 Guiyang, China.
Planetary Science Institute, State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, 430074 Wuhan, China.
Sci Adv. 2024 Sep 20;10(38):eadn2301. doi: 10.1126/sciadv.adn2301.
Magnetite is rare on the Moon. The ubiquitous presence of magnetite in lunar soil has been hypothesized in previous Apollo Mössbauer spectroscopy and electron spin resonance studies, but there is currently no mineralogical evidence to prove it. Here, we report a large number of submicroscopic magnetite particles embedded within iron-sulfide on the surface of Chang'e-5 glass, with a close positive correlation between magnetite content and the TiO content of the surrounding glass. The morphology and mineralogy of the iron-sulfide grains suggest that these magnetite particles formed via an impact process between iron-sulfide droplets and silicate glass melt, and ilmenite is necessary for magnetite formation. Magnetite in lunar glass is a potential candidate for the "magnetite-like" phase detected in the Apollo era and suggests that impact-induced submicroscopic magnetite may be ubiquitous in high-Ti regions of the Moon. Moreover, these impact-induced magnetite particles may be crucial for understanding the lunar magnetic anomalies and mineral components of the deep Moon.
磁铁矿在月球上很罕见。在之前的阿波罗穆斯堡尔光谱和电子自旋共振研究中，曾假设月球土壤中普遍存在磁铁矿，但目前尚无矿物学证据来证明这一点。在此，我们报告了嫦娥五号玻璃表面嵌入在硫化铁中的大量亚微观磁铁矿颗粒，磁铁矿含量与周围玻璃的TiO含量之间存在密切的正相关关系。硫化铁颗粒的形态和矿物学表明，这些磁铁矿颗粒是通过硫化铁液滴与硅酸盐玻璃熔体之间的撞击过程形成的，钛铁矿是磁铁矿形成所必需的。月球玻璃中的磁铁矿是阿波罗时代检测到的“类磁铁矿”相的潜在候选物，这表明撞击诱导的亚微观磁铁矿可能在月球的高钛区域普遍存在。此外，这些撞击诱导的磁铁矿颗粒对于理解月球磁异常和月球深部的矿物成分可能至关重要。
