地球学报2026，Vol.47Issue(3)：555-564,10.DOI:10.3975/cagsb.2026.032421
L6型普通球粒陨石茂名的岩石学、地球化学和年代学研究
Petrology,Geochemistry,and Geochronology of the L6 Ordinary Chondrite Maoming Meteorite
摘要
Abstract
The Maoming meteorite,an L6 ordinary chondrite from a witnessed fall in 2025,is characterized by fresh preservation,negligible terrestrial weathering(W0),and a low degree of shock metamorphism(C-S2).In this study,the petrography,geochemistry,and phosphate U-Pb chronology of the Maoming meteorite were systematically investigated using scanning electron microscopy,bulk major-and trace-element analyses,and in-situ SHRIMP U-Pb dating.The sample exhibited indistinct chondrule boundaries and extensive silicate recrystallization.Its mineral assemblages,petrographic textures,and major-and trace-element compositions were comparable to those of previously reported L6 ordinary chondrites.The rare earth element pattern was nearly flat,with no significant Eu anomaly.Chlorapatite yields a weighted mean 207Pb/206Pb age of(4 480±12)Ma,which was younger than previously reported ages for weakly shocked L6 ordinary chondrites.Moreover,its U-Pb isotopic system showed no evidence of reset related to the～470 Ma breakup of the L-chondrite parent body.These results indicate that the Maoming meteorite was derived from the middle to deep interior of the L-chondrite parent body,where it underwent extensive thermal metamorphism followed by slow cooling,without significant melt differentiation.Therefore,it provides a critical end-member constraint on the late-stage cooling history of L6 ordinary chondrites.关键词
L6型普通球粒陨石/茂名陨石/年代学/地球化学Key words
L6-chondrite/Maoming/geochronology/geochemistry分类
天文与地球科学引用本文复制引用
月程,车晓超,龙涛,王子尧,王慧敏,王晨,刘敦一..L6型普通球粒陨石茂名的岩石学、地球化学和年代学研究[J].地球学报,2026,47(3):555-564,10.基金项目
本文由国家重点研发计划(编号:2022YFF0704905)、上海科技馆陨石微结构与化学研究科研创新平台开放课题、国家自然科学基金(编号:42241107)和天问三号任务关键技术攻关项目(编号:TW3004)联合资助. This study was supported by National Key Re-search and Development Program of China(No.2022YFF0704905),the Open Project for Innovative Platform of Meteoritical Research,Shanghai Science and Technology Museum,National Natural Science Foundation of China(No.42241107),and the Key Technology Research Project of TW-3(No.TW3004). （编号:2022YFF0704905）
