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To understand the effects of substantial topographic relief on deformation localization in the seismically active mountains, like the Longmen Shan thrust belt in the eastern Tibet, sandbox experiments were performed based on the framework of the critical taper theory. First, a reference experiment revealed that the critical taper angle was 12° for our experimental materials. Subsequently, different proto wedges (subcritical (6° in taper angle), critical (12°), and supercritical (20°)) were introduced to cover the range of natural topographic relief, and we used two setups: setup A considered only across‐strike topographic relief, whereas setup B investigated along‐strike segmentation of topography, consist of two adjacent proto wedges. In all experiments, thrust wedges grew by in‐sequence accretion of thrust sheets. Setup A revealed an alternating mode of slip partitioning on the accreted thrusts, with large‐displacement thrust and small‐displacement thrust developing in turn. And contrasting wedge evolutions occurred according to whether the proto wedge was subcritical or critical‐supercritical. In setup B, the differential deformation along the strike produced transverse structures such as tear fault and lateral ramp during frontal accretion. The observed tear fault and its associated thrust system resemble the seismogenic fault system of the 2008 Mw7.9 Wenchuan earthquake. Our experimental results could also explain first‐order deformation features observed in the Longmen Shan. Consequently, we conclude that topographic features, including topographic relief across the range and along‐strike segmentation of topography, contribute significantly to the kinematics and deformation localization in such active mountains.

Speaker verification systems have achieved great progress in recent years. Unfortunately, they are still highly prone to different kinds of spoofing attacks such as speech synthesis, voice conversion, and fake audio recordings etc. Inspired by the success of ResNet in image recognition, we investigated the effectiveness of using ResNet for automatic spoofing detection. Experimental results on the ASVspoof2017 data set show that ResNet performs the best among all the single-model systems. Model fusion is a good way to further improve the system performance. Nevertheless, we found that if the same feature is used for different fused models, the resulting system can hardly be improved. By using different features and models, our best fused model further reduced the Equal Error Rate (EER) by 18% relatively, compared with the best single-model system.

In this article, we present in situ U-Pb and Lu-Hf isotope data for Upper Triassic detritus in the Sichuan region of northwestern South China, which was a foreland basin during the Late Triassic. The aim is to determine the provenance of sediments in the foreland basin and to constrain the evolution of the surrounding mountain belts. U-Pb age data for the Late Triassic detrital zircons generally show populations at 2.4-2.6 Ga, 1.7-1.9 Ga, 710-860 Ma, 410-460 Ma, and 210-300 Ma. By fitting the zircon data into the tectonic, sedimentologic, and palaeographic framework, we propose that the north Yangtze Block and South Qinling-Dabie Orogen were the important source areas of sediments in the northern part of the foreland basin, whereas the Longmen Shan thrust-fold belt was the main source region for detritus in other parts of the foreland basin. The South Qinling-Dabie Orogen could also have served as a physical barrier to block most detritus shed from the southern North China Block into the foreland basin during the sedimentation of the Xujiahe Formation. Our results also reveal that part of the flysch from the eastern margin of the Songpan-Ganzi region had been displaced into the Longmen Shan thrust-fold belt before the deposition of the foreland basin sediments. In addition, the Lu-Hf data indicate that Phanerozoic igneous rocks in central China show insignificant formation of the juvenile crust.