## 4 Results  
This study utilized the SBAS-InSAR technique to derive deformation results along the line-of-sight (LOS) direction. The analysis utilized ascending orbit data from July 2021 to September 2022 and descending orbit data from July 2021 to October 2022, obtained from the Sentinel-1 satellite, as illustrated in Figures 4 and 5. The maximum deformation rate identified from both the ascending (Figure 4) and descending (Figure 5) orbits was -13 mm/year.  
The Hongya Village landslide developed on the right coast of the Nannmerxia River (west bank) in the transition zone of low hills and valley plains northwest of Hongya Village. The landslide was a \"traction-creep slip-push\" composite landslide, and the plane morphology was \"triangular\". The landslides on the northern and western sides were bounded by the back wall of the watershed and the steep and gentle junction, respectively, and the shear exit was the foot of the slope. The comprehensive analysis of the ground and borehole data demonstrated that the landslide was a \"traction-creep slip-push\" composite mega-landslide.  
The average length, width, and thickness of the landslide body were approximately 640 m, 1000 m, and 40.0 m, respectively. The main sliding direction was 95-170\({}^{\circ}\), the area was approximately 64.0 \(\times\) 104 m\({}^{2}\), and the preliminary estimation of the square volume was 2560.0 \(\times\) 104 m\({}^{3}\). The elevation at the front and rear edges of the landslide was 2549.0 m and 2710.0 m, respectively, with an overall slope of approximately 20\({}^{\circ}\). The back wall was smooth, with a circular chair shape and visible scratches. The back wall of the present landslide was 20-40 m high, with a steep slope, forming a two-stage platform with the front edge of the platform being 15-22 m high. The primary platform was 25-38 m long and approximately 220 m wide, with an overall slope of approximately 15\({}^{\circ}\). The secondary platform was 25-35 m long and approximately 400 m wide, with a gradient of 10-20\({}^{\circ}\). The surface of the landslide protruded from the slope and was slightly curved, and its overall slope morphology was convex, with an irregularly curved leading edge (Figure 6).  
Figure 4: The deformation outcomes derived from Sentinel-1A ascending orbit data.  
Regarding the spatial morphology, the western side of the driving school was \"semi-circular\" and of the traction mudstone creep-slip type. The shear exit was situated at the base of the incline, which featured a short range and low speed. The northern side of the three middle schools was of the \"long tongue\" type, with the first crack creeping-sliding after the push bulge. The shear exit was located in the original ditch channel gully, consisting of a high medium-range high-speed airwave that destroyed and buried the school building, with an accumulation thickness of 13.5 m (ZK28). The trees on the southern side of the slope were broken in a \"drunkard\" shape. The instability of the high, steep critical surface formed by tension crack creeping-sliding led to a situated push. The undisintegrated slider was partially attached to the back wall to form a stacked tile after the middle Range-Gorge groove source broke the wall. The original cistern was relocated by 72 m. Pushing, bulging, and sliding occurred on the western side of the slide in Community 2 of Hongya Village, burying the houses. The region from the hill to the north of the mixing plant was pushed and bulged, and the shear surface morphology varied significantly, with leading-edge inversion and roadway bulging. An \"L\"-type debris flow occurred along the original channel from the landslide break wall on the northern side of the Xiao-caizi ditch to the mouth of the ditch, where the slide was plowed. In the mid- to lower sections of the multi-stage ridges, the mouth of the ditch was scraped with a shovel.  
Figure 5: The deformation outcomes derived from Sentinel-1A descending orbit data.