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This paper presents a broad-range study of the co-seismic deformation field of Wenchuan Ms8.0 earthquake by ScanSAR interferometry. The results show co-seismic displacements ranging from −19.8 on the footwall side of the seismogenic fault to 73.6 cm on the hanging-wall side, or from −22.4 to 77.2 cm with atmospheric-delay correction by MODIS. These results differ from the GPS line-of-sight results by 4.58 cm to 2.78 cm, respectively, on the average. We could not obtain the displacements near the earthquake-rupture zone due to incoherence problem.

The Ganzi‐Yushu fault (GYF) is one of the most seismically active fault systems in eastern Tibet, having experienced five M > 7.0 earthquakes over the past 300 years. Here, we use Sentinel‐1 InSAR data spanning from 2014 to 2023 to derive the interseismic velocity fields along the GYF. We calculate the strain rate fields for the entire fault system, which reveal localized strain accumulation along the GYF as well as along two secondary faults within the Bayan Har block. The inversion results obtained from the elastic block model indicate left‐lateral strike slip rates of 4.0–6.5 mm/yr along the GYF and five locked segments distributed along strike. Furthermore, we identify two shallow creeping segments on the InSAR velocity maps. Based on the locations of the creeping sections and their temporal decay characteristics, we infer that the shallow creep along the GYF is afterslip of the 2010 Yushu earthquake. Plain Language Summary: The 500 km‐long Ganzi‐Yushu fault is a main fault system in eastern Tibet. Investigating its slip behavior is crucial for assessing earthquake potential and understanding the deformation patterns in the region. Using space geodetic observations, we investigate the slip rate distribution along the Ganzi‐Yushu fault. The energy accumulation along the fault can be divided into five segments, which correspond remarkably well with the historical events. Besides the Ganzi‐Yushu fault, we find that two secondary faults within the Bayan Har block, which had not received much attention before, also exhibit significant seismic hazard. We identify two shallow creeping sections along the fault. By analyzing the spatio‐temporal characteristics of the shallow creeping sections, we confirm that they are associated with postseismic activity of the 2010 Yushu earthquake. Our results give insights into the regional deformation mode and seismic hazard. Key Points: Our large‐scale high‐resolution InSAR velocity fields reveal strain accumulation within the Bayan Har blockThere are five locked segments distributed along the Ganzi‐Yushu fault, which corresponds well with historical eventsWe identify two transient shallow creeping segments associated with afterslip of the 2010 Yushu earthquake [ABSTRACT FROM AUTHOR]

Ground surface deformations can be observed during the coseismic and postseismic periods. The accurate determination of displacements is of paramount importance for the assessment of the destructive power of large earthquakes and the characterization of fault behaviors. Therefore, we employ the sub-daily Global Positioning System (GPS) solutions at 19 GPS stations to determine the coseismic and postseismic deformations of the 2010 moment magnitude (Mw) 8.8 Maule earthquake. Using sub-daily GPS data, we can accurately measure both coseismic and early postseismic deformation signals, which can precisely identify the distribution of coseismic slip and the spatiotemporal evolution of early afterslip within the first 36 h. In particular, the sub-daily solution can provide more accurate and quicker results, nearly 10% smaller than those with the daily solution. Furthermore, there is significant ground motion in the immediate postseismic period, which decreases rapidly thereafter. The largest postseismic deformation observed during the first 2 h occurred at station CONZ and amounted to 3.6 cm. During the immediate postseismic period of the 2010 Maule earthquake, afterslip is the dominant mechanism, while poroelasticity plays a negligible role within the first 36 h. Meanwhile, early aftershocks tend to occur in the boundary and the inner part of the afterslip, indicating that the afterslip has the potential to drive the occurrence of aftershocks in the initial stages of postseismic activity. [ABSTRACT FROM AUTHOR]