In order to clarify the causes and characteristics of the dynamic phenomenon in the east 1104 transport roadway heading face of Weijiadi Coal Mine, and to provide reference for the safety of mine excavation under similar complex geological conditions, the accident was systematically analyzed based on the field monitoring data and geological data. The geological structure of the east 1104 transport trough is complex and the stress environment is harsh. It is adjacent to many goafs and is affected by multiple reverse faults. The thickness of the coal seam varies greatly and is soft and broken. On December 15,2025, in the middle shift, a roof fall and extrusion accident occurred during the face-to-face work of the working face, and the peak concentration of the T1 methane sensor reached 42.56 %. Through the analysis of the accident process, dynamic phenomenon characteristics and influencing factors, it is determined that the direct causes of the accident include complex stress superposition, abnormal thickening of coal seam thickness, tectonic extrusion, insufficient stress unloading and untimely advance support. The abnormal gas emission is derived from the gas desorption of the caving coal body and the surrounding unloading coal body. The research results show that the accident is a dynamic phenomenon of abnormal gas emission caused by roof caving, which provides theoretical basis and practical guidance for the safety prevention and control of mine excavation in complex geological areas.