KREEP‐Bearing Noritic Lower Crust Under Apollo Basin: Constraints From High‐Mg Impact Glasses in Chang'e‐6 Soil
Le Zhang, Jingyou Chen, Zexian Cui, Yuqi Qian, Chengyuan Wang, Zhiming Chen, Pengli He, Fangfang Huang, Qing Yang, Jintuan Wang, Linli Chen, Yan‐Qiang Zhang, Yi‐Gang XuAbstract
The Moon's crust is proposed to be composed of an anorthositic upper crust and a noritic lower crust. While the upper crust was the result of the floatation of plagioclase crystallized at the late‐stage of lunar magma ocean (LMO), the petrogenesis of the lower crust is in debate. In this study, we found three high‐MgO impact glasses in the Chang'e‐6 lunar soil, one being troctolitic (P032) and other two being noritic (P133 and P138). A combination match suggests P133 and P138 likely originated from the Apollo basin's peak ring, representing lower crust at Apollo basin. The high Mg# and rare earth element signatures of both glasses support a petrogenesis involving the assimilation of KREEP‐bearing crust by partial melts derived from early mafic cumulates of the LMO. This study hence indicates that despite the predominant concentration of KREEP material on the lunar nearside, KREEP components are also locally present on the farside.