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Background: We have generated gene expression databases for human glial precursors, neuronal precursors, astrocyte precursors and neural stem cells and focused on comparing the profile of glial precursors with that of other populations.

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The Hailar–Tamtsag Basin (HTB), an important component of the late Mesozoic extensional basin system in Northeast (NE) China, is characterized by episodic rifting, dramatic magmatism, and thick terrestrial sediments, which provides crucial opportunities to understand late Mesozoic tectonomagmatic events in NE China. However, the previously established late Mesozoic chronostratigraphic framework in the basin remains problematic due to limited isotopic chronological constraints. Here, we present 28 new zircon U–Pb ages for the volcanic rocks from the HTB, which allow us to establish a refined chronostratigraphic framework for the late Mesozoic terrestrial strata. Newly calibrated results indicate that the depositional ages of the Tamulangou and Tongbomiao formations are constrained to ca. 157–148 and ca. 142–137 Ma, respectively; the depositional ages of the Lower Nantun and Upper Nantun members are constrained to ca. 131–120 and ca. 117–111 Ma, respectively. Combining these results with previous studies on sedimentation, structural deformation, and magmatism, the Late Jurassic–Early Cretaceous tectonostratigraphic evolution of the HTB is reconstructed, and three major phases of intracontinental deformation are identified. The HTB experienced extensional deformation in the Late Jurassic due to the break‐off of the subducted oceanic slab of the Mongol–Okhotsk Ocean and subsequent gravitational collapse of orogenically thickened crust following the closure of the ocean basin. Then, in the latest Jurassic–earliest Cretaceous, the evolution of the HTB was dominated by compressional deformation related to flat‐slab subduction of the Paleo‐Pacific Plate. During the Early Cretaceous, an extensional regime resumed in the HTB in response to rollback of the subducting Paleo‐Pacific Plate.

This study presents new whole-rock major and trace element geochemistry, zircon U-Pb ages, and Hf-isotope compositions for volcanic rocks from the Manketouebo Formation of the central Great Xing'an Range, NE China. These data provide precise ages and information on the petrogenesis and source of the magmas that formed this formation, furthering our understanding of the geodynamic setting of the large-scale late Mesozoic magmatism in the Great Xing'an Range and other areas in NE China. The Manketouebo Formation in the study area is dominated by rhyolites and rhyolitic tuffs with minor trachydacites. The LA-ICP-MS zircon U-Pb dating indicates that these volcanic rocks formed between 143 and 139 Ma. The volcanic rocks contain high silica (66.70-79.91 wt.%) and total alkali (5.93-9.72 wt.%) concentrations, and low concentrations of MgO (0.08-1.15 wt.%), total FeO (0.68-4.50 wt.%), and CaO (0.10-2.56 wt.%). They are enriched in large-ion lithophile elements (LILEs; e.g. Rb, Th, and U) and light rare earth elements (LREEs), and depleted in high field strength elements (HFSEs; e.g. Nb, Ta, Ti, and P) and heavy rare earth elements (HREEs), indicating that they are similar to highly fractionated I-type igneous rocks. All of the magmatic zircons from the analysed samples have high initial 176 Hf/ 177 Hf ratios (0.282900-0.283093), positive ε Hf (t) values (7.48-14.19), and young Hf two-stage model ages (954-344 Ma) that suggest the primary magma that formed the volcanic rocks of the Manketouebo Formation was derived from the partial melting of Neoproterozoic to Phanerozoic juvenile crustal material, indicating in turn that significant crustal growth occurred at this time within the Xing'an Terrane. These data, combined with previous research into the spatial-temporal distribution of Mesozoic volcanic rocks in NE China, suggest that the Early Cretaceous magmatism in the Great Xing'an Range was influenced by both the subduction of the Palaeo-Pacific Plate and the closure of the Mongol-Okhotsk Ocean. This was a crucial period in the transformation from the Mongol-Okhotsk Ocean to the Palaeo-Pacific tectonic regimes. In summary, the early stages of Early Cretaceous magmatism in this area were related to the closure of the Mongol-Okhotsk Ocean, whereas the later stages of magmatism in this area and elsewhere in NE China were related to the subduction of the Palaeo-Pacific Plate. ARTICLE HISTORY

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