On 18 December 2023, a magnitude 6.2 earthquake occurred in Jishishan County, Linxia Prefecture, Gansu Province, which resulted in the collapse of buildings, landslides, sand surges and other disasters, with thousands of casualties. This event represents the most serious loss of earthquakes of magnitude 6 or above in China in recent years. A comprehensive analysis of regional environmental conditions and geological hazards development characteristics can be obtained. The Lajishan area is characterised by high altitude, complex terrain, the development of the north-west direction of the Lajishan fracture zone, and the region of the fourth system loess development is thicker. This is prone to seismic impacts, which can produce creeping slippage and pulling cracks, resulting in damage to the formation of landslides and other disasters. A hierarchical analysis method was employed to comprehensively consider five influence factors: faults, stratigraphic lithology, vegetation cover, slope and precipitation. This revealed that regional geological hazards are mainly affected by earthquakes, with a weighting of 56%. Stratigraphic influence was found to be second, accounting for approximately 23%, while precipitation influence was the smallest, accounting for approximately 4%.The geological hazardous area in the study area is concentrated in the area along the front edge of Lajishan, with the epicentre situated at the centre. This is essentially the same as the range of the VIII intensity zone, and is distributed in the shape of a strip. Geological hazard points are primarily influenced by the soft geological environment, concentrated in the lower plate of the Lajishan fracture zone, particularly in Jishishan County, Dazhuohe Township, Baizang Township, and other areas where the distribution of disasters is intense and significantly affected by earthquakes. Therefore, it is crucial to prioritize monitoring and prevention efforts, while also ensuring sufficient attention is devoted to the protection project of the fourth system loess layer. In addition, the regional quaternary loess layer protection project should be given particular attention. In the context of the dense distribution of aftershocks, there are no or few geological disaster sites. This suggests that the main earthquake released a significant amount of stress, which induced major geological disasters. After many aftershocks, the stress state of the rock body tends to be balanced, and the geological structure is rearranged and stabilised after the earthquake. This reduces the further occurrence of geological hazards.
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