高校地质学报2025，Vol.31Issue(3)：286-300,15.DOI:10.16108/j.issn1006-7493.2024047
月球镁质斜长岩陨石NWA 8599的岩相学与矿物化学研究
Petrography and Mineralogy of Lunar Magnesian Anorthositic Meteorite Northwest Africa 8599
摘要
Abstract
Northwest Africa(NWA)8599 is a lunar breccia meteorite found in Northwest Africa.We performed detailed petrographic and mineralogical study on this lunar meteorite.Our observations reveal that NWA 8599 is an olivine-rich magnesian anorthositic noritic breccia,with abundant mineral fragments and minor fine-grained magnesian anorthosite clasts.Our NWA 8599 sample contains a coarse-grained highly magnesian olivine fragment(Fo=84-87),which is closely associated with highly magnesian pyroxene(Mg#=85-89)and geikielite(Mg#=52-54).The geikielite grains in NWA 8599 are reported for the first time among lunar meteorites and mission-returned lunar samples.The CaO contents in the highly magnesian olivine and thermobarometric calculations of pyroxenes indicate that the highly magnesian mineral assemblage is likely derived from a highly magnesian rock from deep crust of the Moon.Our results show large variations in modal abundance and grain size for the magnesian anorthosites in NWA 8599,indicating diversity of the magnesian anorthositic lithologies in the Moon.We suggest that the magnesian anorthosites may be produced by variable degrees of assimilation of primordial ferroan anorthositic crust by mantle-derived magnesian melt during lunar mantle overturn.关键词
镁钛矿/Northwest Africa 8599/镁质斜长岩/月球陨石/月球背面Key words
geikielite/Northwest Africa 8599/magnesian anorthosite/lunar meteorite/lunar farside分类
地质学引用本文复制引用
张真光,张浪,杜天然,赵凯,张爱铖..月球镁质斜长岩陨石NWA 8599的岩相学与矿物化学研究[J].高校地质学报,2025,31(3):286-300,15.基金项目
国家自然科学基金(42025302)资助 （42025302）
