1. College of Earth Sciences, Jilin University, Changchun 130061, China; 

 The Beishan pluton in Gansu of China was selected as the simulated model. The simulation results indicate that the formation of unloading joints in granite is mainly in?uenced by the unloading rate of con?ning pressure. Among the rates tested, the slowest unloading rate 0.025 MPa/s is found to be most conducive to the development of unloading joints. Therefore, a slower unloading rate is favourable for the occurrence of unloading joints. A series of simulations with varying initial depths of uplift ranging from 900 m to 200 m were conducted. The results con?rm that when the specimen rises to a depth of 550–500 m, the unloading joints begin to form. The uplift from a depth of 700–500 m, with variations in both vertical and lateral unloading rates, was simulated. The generation of unloading joints exhibits a negative correlation with vertical unloading and no correlation with lateral unloading, indicating that the unloading joints are mainly controlled by the unloading of vertical pressure. Throughout the simulation process, the vertical joints exhibit irregular and unrealistic regularity, suggesting a more complex formation mechanism than that of the unloading joints.