No matter violent & terrorist incidents or explosion accidents,parameters related to the explosion source,such as explosive equivalent,are always important for the post-explosion accident investigation.The characteristic trace of the medium under explosion load is an important basis for tracing the cause of an explosion accident and obtaining the corresponding explosion source parameters.After reviewing the typical research progress of explosive characteristic traces,including explosion crater,damage of surrounding buildings,and personnel damage degree,it is found that there are significant differences in the shape and size among the explosion craters created by near surface explosions,exposed surface explosions and explosions with certain depth.This research is based on an underground explosion accident in a gold mine in 2021,which was caused by that the dropped welding slag from the shaft ignited the underground combustible materials and explosive equipment.According to the sizes of three explosion craters formed at the accident site,the TNT equivalents are calculated as 654.17 kg,232.49 kg and 193.83 kg,respectively.Then,the particle vibration velocity and the shock wave overpressure of the shaft wall are calculated as 40 cm/s and 2129 Pa,according to the TNT equivalents.The calculation results are consistent with the damage degree of the cage and shaft wall.