## 1 Introduction  
Since the Jinsha River is affected by the complexity of geological tectonic movement, especially the deep rivers, steep terrain, and complex geological conditions, it is prone to landslides [1; 2; 3]. Baiyu-Gongjue is a region in the upper reaches of the Jinsha River that suffers from medium- to large-scale landslides. In late 2018 (11 October and 3 November 2018), Baige landslides occurred successively in Boro Town, Tibet, China, causing upstream inundation and downstream flooding [4; 5]. Although timely post-disaster emergency measures alleviated the two blockages, the dam created by the landslide raised the water level in a matter of days, and the high water seeped into the mountains along the Jinsha River, reviving many ancient landslides in the region. Many scholars have studied the evolution and process of the Baige landslides before and after the disaster [6; 7; 8; 9; 10; 11], but they have largely ignored the potential danger of the resurrected ancient landslides along the Jinsha River, which may lead to disaster events similar to the Baige landslides. Historically, many landslides have been induced by single landslide instability [12]. Due to the complexity of the relationship between internal structures and triggering factors, landslide processes vary even on adjacent slopes with similar geological and topographical conditions. The Xiaomojiu landslide is a large-scale landslide located 5 km upstream of the Baige landslide, with a height difference of about 750 m and an area of about 0.86 km\({}^{2}\); it may cause a catastrophic event similar to the Baige landslide once destroyed. However, the attendant ground displacement and possible risk have not been quantitatively monitored or simulated [9]. The impact of the Baige landslide on the resurrection of the Xiaomojiu landslide has not been analyzed in-depth. Ground displacement is among the most critical parameters for observing changes and movement trends of the landslide [10]. As an effective means to obtain deformation data, Interferometric Synthetic Aperture Radar (InSAR) technology has made remarkable achievements in identifying and monitoring geological hazards such as landslides [13; 14; 15; 16; 17; 18; 19; 20; 21]. Traditional InSAR and pixel-offset tracking (POT) methods are widely applied in landslide deformation monitoring, which uses phase and intensity information. The former is more suitable for identifying small deformations at the cm level, whereas the POT method is more suitable for monitoring large deformations above the meter level [22]. For example, [PERSON] et al. applied the POT method and calculated the large-scale displacement of the Baige landslide. Their results showed that the cumulative maximum displacement reached 25 m from July 2017 to July 2018 [1]. Their deformation data were along the LOS (line of sight) or azimuth directions. However, the landslide's evolution process is very complex, and its movement and displacement are often not in the LOS or azimuth directions. Therefore, observational results from a single direction are often not accurate enough to describe the landslide movement [23]. It is necessary to use multi-orbit SAR data to obtain three-dimensional deformation information on landslides through deformation data in three directions. The water level of the Jinsha River rose in a short time due to the Baige landslide dam. The infiltration of groundwater increased slope weight, reduced soil cohesion, and intensified the slope's erosion by the river, resulting in the revival of many ancient landslides. The Xiaomojiu landslide is the most active of these large-scale landslides and has potential dangers. Thus, we studied the deformation characteristics and potential hazards of the Xiaomojiu landslide for this paper. The Xiaomojiu landslide deformation data were accurately obtained from three observation angles and based on 96 scenes of SAR data over two years.