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• 937–933 Ma and 896–891 Ma magmatism occurred in the Bureya Block. • 937–891 Ma magmatic rocks formed in a continent arc setting. • The Bureya Block has an affinity to the northwestern margin of Rodinia. The Bureya Block, located in the easternmost segment of the Central Asian Orogenic Belt (CAOB), is one of the least understood blocks in Russian Far East. Here we describe newly discovered Neoproterozoic magmatic rocks along the Bureya River in the northern Bureya Block. LA–ICP–MS zircon U–Pb dating demonstrates that these rocks were emplaced in two stages during the early Neoproterozoic: (1) 937–933 Ma, forming an intrusive rock association of gabbros, granodiorites, and monzogranites; and (2) 896–891 Ma, representing by a suite of syenogranites. The good correlation on the Neoproterozoic to Late Triassic geological events between the Jiamusi and Bureya blocks suggests the two blocks formed a contiguous crustal unit. Field observations, together with petrographic and geochemical features, and zircon Hf isotopic data, indicate a magma mixing/mingling origin for the 937–933 Ma gneissic granitoids and amphibolites, with the felsic melts generated by partial melting of a dominantly Mesoproterozoic lower crustal source with possible little addition of ancient crustal materials, whereas the mafic melts were derived from partial melting of a depleted lithospheric mantle wedge metasomatized by fluids dehydrated from the subducted oceanic slab. In addition, the 896–891 Ma syenogranites share a common crust source with the 937–933 Ma granitoids but experienced extensive assimilation and fractional crystallization during magma ascent and evolution. In the context of assembly, growth and breakup of the Rodinia supercontinent, together with the recognition of Neoproterozoic continental arc-type magmatic rocks in the Bureya–Jiamusi Block as well as the nearly coeval subduction-related magmatism recorded elsewhere on the globe, such as Seychelles, Madagascar, India, Lhasa, South China, and Australia, we conclude that the 937–891 Ma magmatism in the Bureya Block resulted from the Andean-type orogeny that formed along the northwestern margin of the Rodinia supercontinent. [ABSTRACT FROM AUTHOR]

Abstract The Bureya Massif is located in the eastern segment of the Central Asian Orogenic Belt (CAOB) and its tectonic affinity and Precambrian evolution is highly controversial. Here we present mineralogical, whole-rock geochemical (major and trace elements and Sm–Nd isotopes) and zircon Hf isotopic data, together with zircon geochronological and mica 40Ar/39Ar dating of the biotite and amphibole gneisses from the Tulovchikha metamorphic complex (previously considered as Archean or Paleoproterozoic basement) in the Bureya Massif, in order to investigate their protolith, metamorphic and deformation ages, petrogenesis, and tectonic implications. LA-ICP-MS U–Pb dating of magmatic zircons from the biotite gneiss, the amphibole–biotite gneiss, and the amphibolite yields single zircon age populations cluster at ~950 Ma, ~920 Ma and ~940 Ma, respectively. The narrow zircon age ranges, together with the morphological features of the zircon crystals and the geochemical data, indicate that the studied metamorphic rocks have a magmatic origin and their protoliths were formed in the early Neoproterozoic (i.e., 950–920 Ma). The consistent formation ages further suggest that the Neoproterozoic gabbro–granitic rocks within the Nyatygran Complex in the Bureya Massif probably represent the protolith of the studied metamorphic rocks. The biotite and amphibole-biotite gneisses of the Tulovchikha metamorphic complex yield whole-rock Nd model ages (t Nd(DM)) of 2.4–1.5 Ga and Hf zircon crustal model ages (t Hf(C)) of 1.7–1.2 Ga, indicating that the precursors of the Tulovchikha Complex gneisses formed from the reworking of Meso–Paleoproterozoic rocks or mixed Neoproterozoic juvenile and Meso–Paleoproterozoic crustal sources. Considering that the Bureya and Jiamusi massifs experienced similar Neoproterozoic magmatic events, we suggest that these massifs form a contiguous crustal unit and share a common geological history. The rocks of Tulovchikha metamorphic complex in the studied area experienced epidote-amphibolite to amphibolite facies metamorphism probably in the early Paleozoic, as evidenced by the 471 ± 19 Ma age of a metamorphic zircon with a low Th/U ratio (<0.1). According to 40Ar/39Ar biotite dating of the biotite gneiss, the Tulovchikha Complex experienced a youngest thermal event at 227 ± 3 Ma. This event may be related to the final closure of the Paleo-Asian Ocean, or may have been caused by the deformation of the blocks of East Asia in connection with the initial stages of the closure of the Mongol–Okhotsk Ocean. Graphical abstract Unlabelled Image Highlights • The first geochronological data for the basement rocks of the Bureya Massif have been obtained. • The protoliths of the Tulovchikha metamorphic Complex are the Neoproterozoic magmatic rocks. • The youngest termal event affecting the Tulovchikha Complex occurred at 227 ± 3 Ma. • Bureya and Jiamusi massifs probably have a common geological history. [ABSTRACT FROM AUTHOR]

Abstract: Speleothem records in southeastern China provide key evidence for past environmental changes. However, the climatic interpretation of these proxies has remained a great controversy. Earlier work interprets the cave δ18O signal associated with regional rainfall of the East Asia Summer Monsoon (EASM) or monsoon rainfall upstream of China. Recent isotope modeling supports the latter but show little correspondence between the precipitation δ18O and rainfall in China. Here, we examine the evolution of the climate and precipitation δ18O for the last 21,000 years in models and observations. Recognizing the regional difference of the EASM rainfall, we propose an interpretation of the Chinese δ18O record that reconciles its representativeness of EASM and its driving mechanism of upstream depletion. The δ18O records do represent the intensity of the EASM system. The monsoon intensity is best characterized by enhanced southerly monsoon winds, which correlate strongly with negative δ18O over China and enhanced monsoon rainfall in northern China, as well as the continental scale Asian monsoon rainfall response in the upstream regions. [Copyright &y& Elsevier]

Background: Gender differences in alcohol use have narrowed in Western societies, but that in Asia has been less investigated. By comparing the 2014 and 2018 waves of the national survey in Taiwan, we aimed to examine the gender differences in population trends in past-month alcohol use, binge drinking, and harmful alcohol use.Methods: The national survey enrolled 17,837 participants in 2014 and 18,626 participants in 2018. Binge drinking was defined as having ≥5 drinks on one occasion in the past month, and harmful alcohol use as having an Alcohol Use Disorders Identification Test score of ≥8.Results: There were significant decreases from 2014 to 2018 in the population's prevalence of past-month alcohol use, binge drinking, and harmful alcohol use. However, males and females had different trends: males showed significant reductions in all three alcohol use behaviours (a decrease of 3.79%, 1.59%, and 2.60%, respectively), while females exhibited a significant rise in harmful alcohol use (from 1.32% to 1.72%), particularly among those aged 18-29 years.Conclusion: There was gender convergence in alcohol use in Taiwan, mainly due to men's decrease and women's increase in harmful alcohol use. Our findings have important implications for the intervention and prevention of the problematic use of alcohol in East Asia. [ABSTRACT FROM AUTHOR]