Lunar mare basalts represent flood volcanism between ~4.0 and 1.2 Ga, therefore, providing insights into the thermal and volcanic history of the Moon. The present study investigates the spectral and chemical characteristics as well as ages of the nearside mare basaltic units from the Grimaldi basin, namely Mare Grimaldi and Mare Riccioli, using a wealth of orbital remote sensing data. This study delineated distinct basaltic units of varying albedo, mineralogy, and titanium contents in both Mare Grimaldi and Mare Riccioli. The crater size–frequency distribution technique revealed that at least two phases of basaltic magmatism spanning ~3.5 to 1.5 Ga (Late Imbrian–Eratosthenian) have occurred in the Grimaldi basin. High‐Ti olivine basalts dated at 2.05 Ga are found to be surrounded by the Late Imbrian (~3.47 Ga) low‐ to intermediate‐Ti basalts in Mare Grimaldi. Low‐ to intermediate‐Ti basalts observed in Mare Riccioli date back to two different volcanic events at ~3.5 Ga and ~3.2 billion years, while patches of basalts having remarkably higher titanium content within the Mare Riccioli record the youngest age of ~1.5 Ga. The chemical trend of the pyroxenes from distinct basaltic units also revealed that multiple events of volcanism have occurred in the Grimaldi basin. The high‐Ti basalts in the Mare Grimaldi crystallized from an Fe‐enriched late‐stage magma while the low‐Ti basalts crystallized from an Mg‐ and Ca‐rich initial magma that experienced an ultra‐late stage quenching. The low‐ to intermediate‐Ti basaltic magma erupted in both the units was derived by partial melting of early cumulate materials from the hybrid source region in the post‐overturn upper mantle and made its way to the surface through dikes that propagated by excess pressures accumulated in the diapirs stalled at the base of the crust due to buoyancy trap. The high‐Ti magma erupted in the Mare Grimaldi was generated by a hot plume ascended from deeper clinopyroxene–ilmenite‐rich cumulate layer near the core–mantle boundary. However, the Eratosthenian (~1.5 Ga) intermediate‐Ti volcanic activity in the Mare Riccioli rather sourced from the ilmenite–clinopyroxene cumulate materials that remained in the upper mantle after mantle overturn. The new results suggest that volcanism had not ceased in the Grimaldi basin at 3.27 Ga, rather it was active and fed by different mantle sources until 1.5 Ga for a period spanning ~2 billion years.

中文翻译：

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月球附近格里马尔迪盆地母马玄武岩的年龄和化学性质：对盆地火山史的启示

月马玄武岩代表〜4.0和1.2 Ga之间的洪水火山活动，因此，提供了有关月球热和火山历史的见识。本研究利用大量的轨道遥感数据，研究了格里马尔第盆地近侧母马玄武岩单元的光谱和化学特征以及年龄，即马里·格里马尔第和马里·里乔利。这项研究描绘了Mare Grimaldi和Mare Riccioli中不同的反照率，矿物学和钛含量的不同玄武岩单元。陨石坑的大小-频率分布技术表明，格里马尔第盆地至少发生了两期玄武岩浆岩相，跨度约3.5至1.5 Ga（晚伊布里亚-埃塔斯托尼亚）。发现日期为2.05 Ga的高钛橄榄石玄武岩被晚伊布连（〜3）包围。马里·格里马尔迪（Gare 47imal）低至中钛玄武岩。在Mare Riccioli中观察到的中低钛玄武岩可以追溯到约3.5 Ga和约32亿年的两次火山事件，而在Mare Riccioli中钛含量显着更高的玄武岩片记录的最低年龄为〜1.5 Ga。来自不同玄武岩单元的辉石的化学趋势还表明，在格里马尔迪盆地发生了多次火山活动。母马格里马尔第高钛玄武岩是从富铁后期岩浆中结晶出来的，而低钛玄武岩是从富含镁和钙的初始岩浆中结晶出来的，并经历了超晚期淬火。在两个单元中喷出的低至中Ti玄武岩浆是通过倾覆后上地幔中杂散源区的早期堆积物的部分熔融而产生的，并通过堤坝进入地表，堤坝由积累的超压传播由于浮力陷阱，底栖动物的底栖动物停滞在地壳的底部。母马格里马尔第火山喷发的高钛岩浆是由岩心-地幔边界附近较深的斜辉石-钛铁矿-富集层中的热羽上升而产生的。然而，马累里乔利中的埃拉斯托森式（〜1.5 Ga）中钛火山活动，其来源是地幔翻转后残留在上地幔中的钛铁矿-斜辉石的堆积物。新的结果表明，格里马尔第盆地（3.27 Ga）的火山活动并未停止，