The area of Lenglongling, located on the northern edge of the Qilian Mountains, has a complex and closely connected network of active fault structures. Over the past 30 years, this region has experienced three moderate to strong earthquakes, demonstrating active seismic activity. Utilized InSAR technology to measure the surface deformation caused by the Menyuan earthquakes in 2016 and 2022, and obtain the detailed slip distribution of the two earthquakes. The aim was to explore the activity characteristics of the Menyuan earthquake sequence, and finally evaluate the static Coulomb stress changes on the faults in the region and its surroundings caused by the Menyuan Mw6.6 earthquake in 2022. The coseismic deformation field in 2016 exhibited a single elliptical uplift center, with predominantly thrust motion. In contrast, the spatial distribution of the deformation field in 2022 was more complex, showing branching phenomena, and there was a slight variation in the rupture direction from west to east, with primarily horizontal deformation. The two earthquakes also differ in their slip patterns and the styles of shallow and deep structures. In 2016, the seismic activity was weak, with low fault dip angles and deep sliding characteristics. However, the earthquake in 2022 is a typical shallow-source earthquake, with a steep rupture surface and a maximum displacement of 3.82m. Combined with the analysis of the focal mechanism of the Menyuan earthquake in 1986, The Lenglongling fault is continuously adapting to new structures and stress adjustments in its north-northeast extension and compressive-shortening activity trend. It is inferred that the Menyuan earthquake sequence is dominated by the activity of the Lenglongling fault. The 2022 Menyuan Mw6.6 earthquake had a significant impact range, and earthquake hazards need to be continuously monitored and further studied, especially the parts where the static Coulomb stress changes exceed the hazard threshold.
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