Composition and origin of the Chang'E‐5 regolith breccias

作者：Zhiming Chen, Le Zhang, Chengyuan Wang, Ya‐Nan Yang, Peng‐Li He, Haiyang Xian, Xiaoping Xia, Jian‐Xi Zhu, Yi‐Gang Xu · 发表于：Meteoritics and Planetary Science · 年份：2025 · DOI：10.1111/maps.70042 · 被引用次数：3 · 研究领域：Geological and Geochemical Analysis、Planetary Science and Exploration、Geology and Paleoclimatology Research

Abstract Numerous studies of basalt clasts in regolith samples returned by the Chang'E‐5 (CE‐5) mission have provided constraints on the timing and nature of the youngest magmatism on the Moon. However, there have been far fewer studies of breccias, one of the main constituents of regolith. Here, we present a comprehensive investigation of the mineralogy, petrology, and U‐Pb geochronology of two CE‐5 regolith breccia samples, which are composed of lithic clasts, agglutinates, glass particles, and mineral fragments. In contrast to the high level of maturity of CE‐5 regolith, the regolith breccias are immature, as judged by their low agglutinate (~11 vol%) and moderate to low matrix contents (~49 vol%). The CE‐5 regolith breccias comprise mainly mare (~90 vol%) and non‐mare (~10 vol%) materials. A low‐Ti mare component of late Imbrian to early Eratosthenian age is identified, in addition to the predominant late Eratosthenian basalts in mare components. Non‐mare components include Mg‐suite norite, highland impact melt clasts, glass particles, and minor fragmented minerals. The glass particles in the CE‐5 regolith breccias are compositionally variable and can be divided into five types, that is, basaltic (mare), KREEP‐rich, feldspathic (highland), Si‐poor, and Si‐K‐rich glasses. Among these glasses, most (65%) are compositionally exotic to the site. The diverse provenance of these “exotic” materials in the CE‐5 breccias is consistent with the multiple ages of Zr‐bearing phases at...