Abstract We obtain the velocity field of present-day crustal motion of the central segment of the Red river fault and adjacent region by using the encrypted GNSS stations and previously published velocity field data. The three-dimensional finite element model of the study area is constructed based on the distribution of active fault in the Sichuan-Yunnan region. We obtain the fault slip rate of different sections of the central segment of Red river fault and strain rate field of study area constrained by GNSS velocities. The results show that the Midu-Yuanjiang segment of Red river fault experiences a right-lateral slip rate of 1.2±0.6 mm/a and a shortening rate of 0.6±0.5 mm/a, and the Yuanjiang-Yuanyang segment of Red river fault experiences right-lateral slip rate of 1.8±0.7 mm/a and a shortening rate of 1.5±0.6 mm/a. The strain rate results show that shear deformation dominates in the central segment of the Red river fault and adjacent region. The maximum shear strain rate appears in the Xiaojiang fault zone with a rate of about 62×10-9/a; the shear deformation is relatively weak along the Red river fault. The dilatation strain rate shows that compressive deformation is significant along the Yuanjiang-Yuanyang segment of Red river fault with the rate of about 10×10-9/a. There is strong coupling along the Yuanjiang-Yuanyang segment, and the seismic hazard of the Yuanjiang-Yuanyang segment deserves more attention.
HUANG Yong,MENG Guojie,WU Weiwei et al. Present-Day Deformation Characteristics of the Central Segment of the Red River Fault Based on GNSS[J]. jgg, 2024, 44(1): 57-62.
HUANG Yong,MENG Guojie,WU Weiwei et al. Present-Day Deformation Characteristics of the Central Segment of the Red River Fault Based on GNSS[J]. jgg, 2024, 44(1): 57-62.