Seismogenic characteristics of the 2025 Dingri M 6.8 earthquake: Insights from GNSS observations
Yu Li, Yuebing Wang, Yinxing Shao, Hongbo Shi, Tan Wang
Abstract
This study investigates the seismogenic characteristics of the 2025 Dingri M S 6.8 earthquake through multi-parametric GNSS analyses of velocity field, strain rate evolution and displacement patterns across pre-seismic and co-seismic phases. Our findings demonstrate spatiotemporally heterogeneous crustal deformation exhibiting kinematic precursors correlating with subsequent rupture propagation. The epicentral region exhibited prolonged N-S compressional strain accumulation accompanied by accelerated E-W extensional deformation and progressive counterclockwise rotation of principal strain axes three years prior, indicating enhanced local normal fault activities. Co-seismic observations delineate significant displacement domains, with the XZSJ (∼95 mm) site documenting the largest northeastward motion, consistent with rupture propagation along secondary N-E trending structures. Co-seismic strain analysis identifies concentrated seismic moment release primarily west of the Xainza-Dinggye Fault and north of the Southern Qinghai-Xizang Detachment Fault system, displaying normal fault kinematics in agreement with the seismic source mechanism. The co-seismic strain partitioning pattern shows critical implications for regional N-S trending normal fault system, necessitating sustained geodetic monitoring to advance understanding of seismic cycle deformation in this area.