A near-surface fine-velocity structure in the western Hoh Xil Basin revealed by first-arrival travel-time tomography from a deep seismic reflection profile

A high-resolution P-wave velocity structure of the western Hoh Xil Basin (HXB) reveals significant upper crustal tectonic deformation linked to thrust faults, providing insights into the region's geodynamic evolution. The study used first-arrival travel-time tomography on a deep seismic reflection profile to map velocities exceeding 4.0 km/s in Triassic flysch deposits and delineate stratigraphic boundaries with unprecedented lateral resolution. Findings indicate substantial crustal shortening (>50%) during the Late Cretaceous to Early Eocene (81–50 Ma) due to the Tanggula thrust, followed by tectonic uplift controlled by the Hoh Xil and Fenghuoshan thrusts from 45 to 28 Ma. Minimal deformation in Neogene and Quaternary layers suggests weak crustal shortening post-Neogene, challenging assumptions about late-stage uplift mechanisms.

Wu, G., Lu, Z., Li, W., Wang, G., Cheng, Y., Chen, S., Cai, Y., Wang, G., & Cai, W. (2025). A near-surface fine-velocity structure in the western Hoh Xil Basin revealed by first-arrival travel-time tomography from a deep seismic reflection profile. Lithos, 494-495, 107923. https://doi.org/10.1016/j.lithos.2024.107923