Petrology and geochemistry of lunar feldspathic meteorite Northwest Africa 11111:Insights into the lithology of the lunar farside highlands
Petrology and geochemistry of lunar feldspathic meteorite Northwest Africa 11111:Insights into the lithology of the lunar farside highlands
复制标题
西北非洲11111月球长石陨石的岩石学和地球化学：月球背面高地岩性的见解
DOI：
10.1111/maps.13743
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发表时间：
2021
影响因子：
2.2
通讯作者：
Hsu Weibiao
中科院分区：
文献类型：
--
作者：
Fu Xiaohui;Cao Haijun;Chen Jian;Hou xuting;Ling Zongcheng;Xu Ling;Zou Yongliao;Tang Chipui;Hsu Weibiao
我们对西北非洲（NWA） 11111月球长石陨石进行了岩石学、矿物学和地球化学研究。该陨石含有多种类型的岩屑，包括长石碎屑、富镁质碎屑、麻粒岩、撞击熔融角砾岩、少量玄武岩碎屑以及在重结晶细粒基质中胶结的高度演化的碎屑。矿物化学和地球化学特征都表明NWA 11111的起源是月球。体积分析表明，NWA 11111是一种典型的月球长石陨石，这与其大量的斜长石碎片和斜长石碎片相一致。月球轨道器任务的地球化学数据比较表明，这块陨石很可能是从月球背面的长石高地发射的。在NWA 11111的三个部分中，在辉石中出现了广泛的脱溶片层（宽度达20 μm），这表明该陨石含有来自月球地壳表面约10公里的成分。镁质斜长岩碎屑普遍存在于该陨石中，表明镁质斜长岩可能是月球背面地壳的重要岩性。NWA 11111的玄武岩碎屑范围从极低钛到低钛的海玄武岩，可能代表月球背面的隐层岩。虽然NWA 11111的KREEPy特征不明显，但存在含有各种硅多晶岩和/或钾长石的高度演化的碎屑。它们可能来自后期残余液体。NWA 11111中的岩屑和矿物碎片为月球背面地壳岩性和岩浆过程的多样性提供了新的见解。这块陨石还提供了来自月球地壳广阔垂直剖面的岩石物质。
We performed a petrological, mineralogical, and geochemical study of the lunar feldspathic meteorite Northwest Africa (NWA) 11111. This meteorite contains several types of lithic clasts, including feldspathic clasts, mafic‐rich clasts, granulites, impact melt breccias, minor basaltic clasts, and highly evolved clasts cemented in a recrystallized fine grain matrix. Both mineral chemistry and geochemical characteristics indicate a lunar origin for NWA 11111. The bulk analysis suggests that NWA 11111 is a typical feldspathic lunar meteorite, which is consistent with its large population of anorthositic clasts and plagioclase fragments. A comparison of geochemical data made by lunar orbiter missions indicates that this meteorite was likely launched from the Feldspathic Highland Terrane on the lunar farside. The chemical zoning, coupled with extensive exsolution lamellae (up to 20 μm in width) occurring in pyroxene across three sections of NWA 11111, demonstrates that this meteorite contains components derived from the surface to about 10 km of lunar crust. Magnesian anorthosite clasts are commonly present in the meteorite, indicating that magnesian anorthosite probably represents an important lithology in the lunar farside crust. Basaltic clasts in NWA 11111 range from a very low‐Ti to a low‐Ti mare basalt, possibly representing cryptomare on the lunar farside. Although a KREEPy signature for NWA 11111 is not evident, highly evolved clasts containing various silica polymorphs and/or K‐feldspar are present. They may originate from late‐stage residual liquids. Lithic clasts and mineral fragments within NWA 11111 provide new insights into the diversity of lunar crust lithology and magmatic processes on the lunar farside. This meteorite also offers rocky materials from a wide vertical section of lunar crust.