Orogenic belts have been among the most important locations to investigate the growth of continental crust (CC). The Eastern Kunlun Orogenic Belt (EKOB), which contains widespread Permian-Triassic granitoids, is volumetrically comparable to the Cenozoic Gangdese magmatic belt in the Tibetan Plateau and is an ideal region to investigate the mechanism of the Paleozoic-Mesozoic CC growth in this region. The Gouli batholith at the eastern end of the EKOB consists of the synchronous Xiangride granodiorite, Asiha quartz diorite (ca. 242 Ma) and adamellite. The granodiorite and quartz diorite, both of which contain magmatic enclaves, show medium-high K, calc-alkalic and metaluminous signatures and have similar rare earth element and trace element patterns to those of bulk CC. Besides, the Xiangride granodiorite displays distinct adakitic signatures (average Sr/Y of 47). The Sr-Nd isotopic values for the different types of rocks are roughly similar ((87 Sr/ 86 Sr) i = 0.708167-0.713553, ε Nd (t) =-6.8 to-5.3), while Hf isotopes are distinguishable, with ε Hf (t) granodiorite = 0.3 to 5.1 and ε Hf (t) diorite =-1.6 to 0.7. These geochemical and petrographic signatures suggest that the granodiorite originated from the partial melting of subducting oceanic crust and terrigenous sediments, and the quartz diorite and enclaves formed via the mixing of slab-derived magma and enriched mantle-derived melt. Further comprehensive analyses of the spatial and temporal distribution of regional magmatic rocks, metamorphism and sedimentary facies reveal that the Gouli batholith and most of the Permian-Triassic granitoids in the EKOB formed during the subduction of the Paleo-Tethys Ocean instead of subsequent syn-collision setting. Thus, we contend that the Permian-Triassic CC growth of the EKOB occurred in a slab

Our ignorance about the tectonic affinity of the western Qinling‐Songpan‐Ganzi tectonic region, which is strategically located between the northeastern corner of the Tibetan Plateau, the northwestern corner of the Yangtze block, and the southwestern corner of the north China block, limits our understanding of the tectonic evolution of east Asia. Basaltic volcanic rocks in the Duofutun area within the west Qinling terrane in Qinghai Province (China), the northernmost part of the Songpan‐Ganzi region, contain coeval magmatic zircons that constrain the eruption age of the host basalts to ∼14 Ma. More significantly, the basalts have entrained zircon xenocrysts from the deep crust that record the presence of unexposed Neoarchean (2.7–2.5 Ga) basement. U‐Pb and Hf isotope data from the xenocrysts reveal that this basement has undergone a complex evolution that includes the addition of new mantle‐derived material at ∼2.7–2.4 and 1.1–0.8 Ga and crustal reworking events at ∼1.8 and 1.4 Ga. Phanerozoic thermal events at 320–300, 230, and 160 Ma have also modified (reworked) the basement. Using these data, we interpret at least the western part of the west Qinling orogenic terrane as a microcontinental block that originally separated from the north China block, closed with the northern Yangtze block during the Meso‐Neoproterozoic, and then redocked with the southern part of the north China block in the Phanerozoic (i.e., early Paleozoic). The west Qinling terrane was then affected by the northward subduction and collision of the Yangtze block in the Paleozoic and early Mesozoic and underwent lithospheric extension in Jurassic time.

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This study compared the efficiencies of two widely used automatic eddy detection algorithms—that is, the winding-angle (WA) method and the vector geometry (VG) method—and investigated the submesoscale eddy properties using surface current observations derived from high-frequency radars (HFRs) in the Taiwan Strait. The results showed that the WA method using the streamline and the VG method based on the streamfunction field have almost the same capacity for identifying eddies, but the former is more competent than the latter in capturing the eddy size. The two algorithms simultaneously identified 1080 submesoscale eddies, with the centers and boundaries determined only by the WA method, and they were further used to investigate the eddy properties. In general, no significant difference was observed between the cyclonic and anticyclonic eddies in terms of radius, life span, and kinematics, as well as the evolution during their life cycles. The typical radius of the eddy in this region was 3–18 km. And a strong correlation was observed between the life span and the radius. The spatial distribution of the eddies indicated that topography played a significant role in the generation of the eddies. And the trajectories of the eddies suggested that all the eddies in this area mostly tended to move southeastward. Statistically, three different stages of the eddy’s life span could be identified by the significant growth and decay of the radius and the mean kinetic energy. This study shows the great capability of HFRs in oceanography research and applications, especially for observing the submesocale dynamics.