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To better understand the lithosphere mantle collision tectonics between the India plate and Asia plate, we determine three dimensional P wave velocity structure beneath western Tibet using 27,439 arrival times from 2,174 teleseismic events recorded by 182 stations of Hi‐CLIMB Project and 16 stations in the north of Hi‐CLMB. Our tomographic images show the velocity structure significantly difference beneath northern and southern Qiangtang, which can further prove that the Longmu Co‐Shuanghu ophiolitic belt is a significant tectonic boundary fault zone. There are two prominent high velocity anomalies and two prominent low velocity anomalies in our images. One obvious high velocity anomalies subduct beneath the Tibet at the long distance near 34°N, whereas it is broke off by an obvious low velocity anomaly under the IYS. We interpret them as northward subducting Indian lithosphere mantle and the low velocity anomanly under IYS likely reflects mantle material upwelling triggered by tearing of the northward subduction Indian lithosphere. The other prominent high velocity anomaly was imaged at a depth from 50 km to 200 km horizontal and up to the northern Qiangtang with its southern edge extending to about 34°N through Hoh Xil block. We infer it as the southward subducting Asia lithosphere mantle. The other widely low velocity anomaly beneath the Qiangtang block lies in the gap between the frontier of India plate and Asia plate, where is the channel of mantle material upwelling. [ABSTRACT FROM AUTHOR]

Whether the central metamorphic belt of the Qiangtang terrane in the Qinghai-Tibet Plateau should be attributed to a suture zone, is still heavily debated, due to inadequate deep structure constraints. Using the data collected from 16 stations in the northern part of the Hi-Climb profile and 16 broadband seismic stations recently arranged in the northern part of Gaize County, this study developed a broadband seismic profile running through the in-situ Central Qiangtang Metamorphic Belt (CQMB) roughly along 84.5°E. Significantly characteristics of the crust and mantle structure beneath the profile were obtained through P-wave receiver function analyses: (i) The south Qiangtang terrane has a complex Moho structure at depth 56–82 km, while the north Qiangtang terrane has a nearly horizontal Moho at depth approximately 62 km. Moreover, the northward-inclining Moho is noticeably dislocated with a maximum offset of approximately 18 km under the CQMB. (ii) The crustal low-velocity zones on both sides of the CQMB are transversely discontinuous and are also distinct from each other. (iii) A northward-subducting interface occurs beneath the in-situ CQMB (34.0°N–34.5° N). Based on the geological outcrops and their petrological analysis, the structural characteristics beneath the CQMB are interpreted as the traces of the Longmucuo-Shuanghu suture zone, which was formed by the northward subduction-collision of the south Qiangtang terrane left after the closure of the Paleo-Tethys Ocean at the end of the Triassic. • Obvious difference in the crust-mantle structure along the Profile 84.5°E in the western Qiangtang through P-wave receiver function analyses. • The northward-inclining Moho structure under the in-situ CQMB is noticeably dislocated, with a maximum offset of approximately 18 km. • The in-situ CQMB is interpreted as the traces of the Longmucuo-Shuanghu suture zone. [ABSTRACT FROM AUTHOR]

• High-resolution structure of the Pn velocity and anisotropy reveals that the average Pn-wave velocity beneath the GMB is 8.13 km/s, higher than that of regular orogenic belts. • Variations of the velocity and anisotropy on both sides of the Jiali dextral strike-slip fault indicate that the JLF as a transcrust is a stress transition boundary within the mantle. • The formation of the rift was attributed to the lithospheric activity within the mantle wedge beneath the Middle-eastern Gangdese Metallogenic belt. The lithospheric mantle wedge beneath the middle-eastern Gangdese Metallogenic Belt (GMB), located at the forefront of the India-Eurasia collision-subduction zone retains many traces of structure evolution, which can be revealed by the velocity and anisotropy structure of the uppermost mantle of this region. In this study, high-resolution structures of the Pn velocity and anisotropy beneath the middle-eastern GMB are presented using interstation Pn differential travel-time data recorded by a dense broadband seismic array. The average Pn-wave velocity of 8.13 km/s beneath the GMB is close to that of the peridotite. The Pn velocity and anisotropy show prominent differences across the Jiali dextral strike-slip fault (JLF, ∼31° N) on the east of Shenza-Xietongmen rift, as indicates that the JLF (31°N) is an uppermost mantle trace of the Shiquan River-Nam Tso Mélange Zone. Low Pn velocity (<8.0 km/s) and a nearly EW-oriented Pn fast-wave direction to the north of the JLF, suggesting the EW extension of the Eurasian plate. NE-oriented Pn fast-wave direction with strange intensity (>0.03) to the south of the JLF indicates the direct influence of the Indian plate northward subduction. The rifts located at the boundary of high and low-velocity anomalies imply that the rift system formed under the influence of lithospheric mantle activity. Based on the NE compression caused by the Indian plate's northeastward subduction, some of the forced upwellings of thermal material generated within the mantle wedge tip caused an EW extension of the crust. Subsequently, the rifts system was locally formed. [ABSTRACT FROM AUTHOR]