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Southeastern (SE) Tibet is one of the most seismically active regions in mainland China, but the spatial distribution of interseismic coupling that quantifies seismic hazard is unknown along most major faults. In this study, we constructed an elastic block model to invert Global Positioning System data for slip rates and locking coefficients along 20 major faults in SE Tibet. Our results identify 27 strongly coupled fault segments with locking coefficients >0.5, defined as potential seismogenic asperities, extending laterally for 36–330 km. Quantitative calculations of seismic moment budgets on these seismogenic asperities indicate that they are capable of generating Mw 6.4–7.7 earthquakes in the next few decades, of which the Anninghe, Daliangshan and Red River faults have the potential for Mw ≥ 7.5 earthquakes. The interseismic coupling model provides a component for probabilistic analysis of future seismic hazards in densely populated Southwest China. Plain Language Summary: In the period between earthquakes, crustal faults are either partially to fully stuck or slipping freely. In the former case, plate movement can cause a buildup of energy on the fault plane and eventually be released through earthquakes. Using Global Positioning System (GPS) to measure the movement of the Earth's surface, we can use models of crustal deformation to identify where and how quickly faults are accumulating energy and then make reasonable predictions about the locations and magnitudes of future earthquakes. Based on the above principles, in this study, we use GPS measurements to suggest the locations and magnitudes of potential earthquakes on 20 major faults in southeast Tibet, which includes most of the Sichuan and Yunnan provinces in southwestern China. We find that 27 fault segments with lengths of 36–330 km are stuck to some degree and accumulating energy. Currently, the accumulated energy can produce earthquakes of Mw 6.4–7.7, highlighting the severity of earthquake hazards in Southwest China. Key Points: We obtained a unified interseismic coupling model for 20 major fault systems in southeastern TibetWe identify 27 seismogenic asperities with locking coefficients >0.5 that could host Mw 6.4–7.7 earthquakesThe interseismic coupling model provides a component for probabilistic analysis of future seismic hazards in Southwest China [ABSTRACT FROM AUTHOR]

The 5 September 2022 Mw 6.7 Luding earthquake occurred on the Moxi segment of the highly active Xianshuihe fault in eastern Tibet. Here, we constrain the coseismic slip by jointly inverting the coseismic displacements measured by Global Positioning System, seismometer and Interferometric Synthetic Aperture Radar. Along the Moxi fault, concentrated left‐lateral strike slip extends ∼30 km along the strike above 10 km depth, producing 0.7–1.0 m shallow slip. Clustered aftershocks and slip inversions suggest that the secondary conjugate Mozigou fault may also involve the rupture. Southward rupture propagation is likely arrested by the barrier‐like fault segments of the Xianshuihe fault, characterized by high interseismic coupling (>0.6) and reduced shear stress rate (<1 kPa/yr) due to interactions with surrounding large locked asperities. The distribution of aftershocks is highly correlated with the positive coseismic Coulomb failure stress changes , which bring the adjacent asperities on the Anninghe and Daliangshan faults ∼0.2 MPa closer to failure. Plain Language Summary: The Mw 6.7 Luding earthquake occurred in eastern Tibet on 5 September 2022, causing 93 casualties and 25 people missing, and substantial damage in the epicentral regions. In this study, we derive the static coseismic displacements from Global Positioning System, seismometer and Interferometric Synthetic Aperture Radar observations. We jointly invert these datasets for the coseismic slip distribution. Our results reveal that the coseismic slip is likely distributed on the conjugate Moxi and Mozigou faults, with the primary slip concentrated on the Moxi fault. We compare the coseismic slip with both the interseismic coupling distribution and shear stress rate on the Moxi fault. We find that the southward coseismic rupture termination is spatially coincident with the areas undergoing a low pre‐earthquake shear stress rate and a high interseismic coupling. The comparison suggests that the coseismic slip during the Luding earthquake is likely controlled by pre‐earthquake interactions with surrounding locked zones on the Anninghe and Daliangshan faults (DLS). We calculate the coseismic Coulomb failure stress changes and demonstrate that the aftershocks could be explained by the induced positive stress perturbations. We conclude that the Luding mainshock enhances earthquake hazards on the Anninghe and DLS. Key Points: Global Positioning System, seismometer, and Interferometric Synthetic Aperture Radar measurements reveal concentrated coseismic slip extending 30 km on the Moxi fault at 0–10 km depthInteractions with large locked asperities lower the shear stress rate to the south of earthquake and lead to the arrest of coseismic ruptureThe Luding event brought the Anninghe and Daliangshan faults ∼0.2 MPa closer to failure, representing enhanced earthquake hazard [ABSTRACT FROM AUTHOR]