^1,2Jinting Kang, ¹Zhengyu Hou, ¹Haochen Yang, ¹Xue Tang, ^2,3Weibiao Hsu, ^1,2Fang Huang
Journal of Geophysical Research: Planets, 131, e2026JE009894
Link to Article [DOI: 10.1029/2026JE009894]
¹State Key Laboratory of Lithospheric and Environmental Coevolution, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China
²Deep Space Exploration Laboratory, Hefei, China
³Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, China

Published by arrangement with John Wiley & Sons

Magma oceans represent a pivotal stage in the early evolution of terrestrial planets. Early-formed asteroids, driven by the decay of ²⁶Al, may have also experienced such magma ocean processes. To investigate potential magma ocean differentiation on asteroid 4 asteroids, we reported high-precision iron isotope data for 25 eucrites and 13 diogenites. Eucrites exhibit a δ⁵⁶Fe range of approximately 0.1‰, varying from −0.044 to 0.073‰, with a mean value of 0.020 ± 0.013‰ (2SE, N = 25). Diogenites display δ⁵⁶Fe ranging from −0.051 to 0.018‰, yielding an average of −0.004 ± 0.011‰ (2SE, N = 13). The observed Fe isotope variation and offset between eucrites and diogenites cannot be produced by terrestrial weathering, impacts, and core formation. Combined with MELTS modeling using two different initial compositions for Vesta, the isotope variation can be explained by magma ocean differentiation. A cross-planetary comparison is made with the Moon, where magma ocean differentiation and associated Fe isotope variations have been extensively studied. Vestan samples exhibit remarkably limited δ⁵⁶Fe variation (∼0.1‰) compared to lunar basalts (∼0.3‰). This dichotomy may reflect distinct magma ocean evolution pathways across planetary bodies: later pyroxene crystallization, the absence of ilmenite-driven mantle overturn, and rapid cooling in the case of Vesta. Thus, planetary geochemical diversity is fundamentally shaped by magma ocean dynamics modulated by body size, composition, and thermal history.

¹Heng-Ci Tian, ¹Wei Yang, ²Huijuan Zhang, ¹Jingyan Cai, ¹Yangting Lin, ³Keqing Zong, ⁴Qi Liu, ⁵Feixiang Liu, ⁶Caihong Gao, ⁷Maoyong He
Journal of Geophysical Research: Planets, 131, e2026JE010077 Link to Article [DOI: 10.1029/2026JE010077]
¹Key Laboratory of Planetary Science and Frontier Technology, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
²East China University of Technology, Nanchang, China
³State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan, China
⁴State Key Laboratory of Critical Mineral Research and Exploration, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
⁵School of Earth Sciences and Engineering, Nanjing University, Nanjing, China
⁶Research Center for Planetary Science, College of Earth Sciences, Chengdu University of Technology, Chengdu, China
⁷State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China

Published by arrangement with John Wiley & Sons

To further constrain the lunar Li isotopic composition and its behavior during lunar magmatic differentiation, we measured twelve lunar meteorites, including mare basalts, Mg-suite rocks and anorthosites. Petrographic observation, dilute acid cleaning, and trace elemental characteristics indicate minimal terrestrial contamination. Low-Ti basalt meteorites yield a restricted δ⁷Li range (2.75 ± 0.52‰ to 3.95 ± 0.16‰), consistent with Apollo low-Ti basalts (3.1∼5.6‰). The Mg-rich norite Arguin 002 shows a similar value, supporting limited Li isotope fractionation during early lunar magma ocean (LMO) differentiation, a conclusion corroborated by modeling results of Li isotopic evolution during LMO differentiation. The heavier δ⁷Li in high-Ti basalts, however, points to the presence of interaction between ilmenite-bearing cumulate-derived melts and the ambient mantle rather than to simple late-stage LMO differentiation. Combining the reported Apollo and La Paz mare basalt meteorites data, we estimate the lunar mantle δ⁷Li to be 3.8 ± 1.3‰, indistinguishable from the Earth’s mantle, implying negligible fractionation during the Giant Impact. In contrast, lunar anorthosites exhibit extreme δ⁷Li variations (−0.7‰ to 9.8‰) with a negative correlation with Li content, likely reflecting impact-driven secondary redistribution. These findings not only confirm the Earth-Moon Li isotopic similarity using meteorites from diverse lunar terrains that complement the Apollo collection but also reveal that the lunar crust has been pervasively modified by impact processes, which have significantly disturbed its primary Li isotopic compositions.