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Diffusion of Tibeto-Burman populations across the Tibetan Plateau led to the largest human community in a high-altitude environment and has long been a focus of research on high-altitude adaptation, archeology, genetics, and linguistics. However, much uncertainty remains regarding the origin, diversification, and expansion of Tibeto-Burman populations. In this study, we analyzed a 7.0M bp region of 285 Y-chromosome sequences, including 81 newly reported ones, from male samples from Tibeto-Burman populations and other related Eastern Asian populations. We identified several paternal lineages specific to Tibeto-Burman populations, and most of these lineages emerged between 6000 and 2500 years ago. A phylogenetic tree and lineage dating both support the hypothesis that the establishment of Tibeto-Burman ancestral groups was triggered by Neolithic expansions from the middle Yellow River Basin and admixtures with local populations on the Tibetan Plateau who survived the Paleolithic Age. Furthermore, according to the geographical distributions of the haplogroups, we propose that there are two Neolithic expansion origins for all modern Tibeto-Burman populations. Our research provides a clear scenario about the sources, admixture process and later diffusion process of the ancestor population of all Tibeto-Burman populations. [ABSTRACT FROM AUTHOR]

High-Mg andesitic rocks (HMAs) at convergent margins can provide crucial insights to the generation of the continental crust and the deep crust-mantle interactions. Here, we report a series of high-Mg diorites in the central Tibetan Plateau, which principally intrude into the Triassic accretionary complexes of the the Zhiduo-Yushu mélange and the central Hohxil-Bayan Har-Songpan-Garzê (HBSG) terrane. The central HBSG diorites yield zircon U Pb ages of 209–210 Ma, while the Zhiduo-Yushu diorites give relatively older zircon U Pb ages of 217–218 Ma. Both of them exhibit the sanukitic HMAs affinities with relatively low ratios of La/Yb and Sr/Y, but the Zhiduo-Yushu diorites have lower Ti-in-zircon temperatures than those of the central HBSG diorites. Geochemical and isotopic signatures indicate that both of them might be formed by partial melting of Triassic turbidites and the subsequent melt-peridotite interactions during a low-pressure and high-temperature condition, although the proportion of sediments involved is different. Our latest data, combined with some data from previously published studies, show that the Triassic HMAs in the central Tibetan Plateau formed in three episodes: 219–229 Ma, 217–218 Ma, and 209–215 Ma. And they show a northeastward younger trend and a significant compositional transition from adakitic HMAs to sanukitic HMAs. These features lead us to propose that melting of the hot subducted oceanic crust and the subsequent melt-peridotite interactions generated the adakitic HMAs, while upwelling of asthenosphere mantle triggered by slab rollback could sustainably provide a sufficiently high-temperature condition for the genesis of the Triassic sanukitic HMAs. And the slab rollback induced the northeastward migration of the arc magmatism in the Triassic accretionary complexes. • This paper reports high-Mg andesitic magmatism in the central Tibetan Plateau. • The magmatism exhibits a compositional transition from adakitic to sanukitic. • Those sanukitic HMAs were formed by sediment melt-peridotite interactions. • Slab rollback triggered a northeastward-migrating accretion arc magmatism. [ABSTRACT FROM AUTHOR]