In order to study the stress effect of the 2025 Dingri, Tibet M6.8 earthquake on the surrounding area, the multi-source focal mechanism solution data were collected in this study, and the central focal mechanism solution parameters were determined as follows: nodal plane I strike 184.37°, dip 47.67°, slip -78.10°; nodal plane II strikes 346.99°, dip 43.66°, slip -102.76°, which is diagnosed as a normal fault earthquake. By analyzing the relative shear stress and normal stress on the fault plane projected by the regional tectonic stress field, it is confirmed that the earthquake is the energy release under the action of regional tectonic stress, and it is preliminarily inferred that the node plane I is the seismic fault plane, and the Dengmecuo fault may be a seismogenic fault. Based on the elastic half-space model and the seismic rupture model, the characteristics of the displacement field and strain field induced by the earthquake are obtained: the horizontal displacement field presents the phenomenon of material gushing out from the east and west sides of the epicenter and a small amount of inflow from the north side. The vertical displacement field is characterized by subsidence in the north of the epicenter and uplift in the northeast. The distribution of volumetric strain and areal strain showed significant regularity. In addition, the estimated Coulomb failure stress increases on the southern segment of the Shenza-Dingjie Fault and the eastern segment of the Lazi-Qiongdoujiang Fault exceeds the triggering threshold of 0.01MPa, which warranting close attention to seismic activity on these faults. The Dengmecuo Fault exhibits the largest stress unloading, further validating its role as the seismogenic fault. The findings in this study provide a critical references for regional seismic hazard assessment.
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