Shock-lithification is a fundamental process of making rocks from fine-grained and porous regoliths on the surface of the Moon. Previous investigations have constrained potential shock pressures during shock-lithification based on experimental and numerical simulations. However, pressure and temperature conditions during shock-lithification have not been directly inferred from natural lunar breccias. Here, we report the discovery of widespread tissintite in strongly shock-lithified lunar meteorites, accompanied occasionally by Si-rich corundum and coesite. The coexistence of tissintite and coesite and the absence of stishovite in molten regions indicate a shock pressure of 4-8 GPa, which might be the pressure boundary between weak and strong shock-lithification. Meanwhile, the presence of Si-rich corundum imposes a temperature constraint of similar to 2,300 K for the intergranular melts. This temperature constraint has profound significance for interpreting the behaviors of volatile and moderately volatile elements and remanent magnetization records during strongly shock-lithification of lunar breccias.
Publication name |
GEOPHYSICAL RESEARCH LETTERS Volume: 48 Issue: 5 Article Number: e2020GL091554 DOI: 10.1029/2020GL091554 Published: MAR 16 2021 |
Author(s) |
Zhang, Ai-Cheng; Jiang, Qin-Ting; Tomioka, Naotaka; Guo, Yan-Jun; Chen, Jia-Ni; Li, Yang; Sakamoto, Naoya; Yurimoto, Hisayoshi |
Corresponding author(s) |
ZHANG Aicheng aczhang@nju.edu.cn -Nanjing Univ, Sch Earth Sci & Engn, State Key Lab Mineral Deposits Res, Nanjing, Peoples R China. -CAS Ctr Excellence Comparat Planetol, Hefei, Peoples R China. |
Author(s) from IGCAS |
LI Yang | View here for the details
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