Large earthquake increasing and decreasing analysis method, system, equipment and medium

The invention discloses a large earthquake increase and decrease analysis method, system and device and a medium, and relates to the technical field of seismic exploration. The method comprises the steps that the fracture half length of a seismic structure is determined; determining a position relationship between the target fracture and the earthquake-generating structure; the position relation comprises that the target fracture and the earthquake-generating structure are parallel to each other or the target fracture is located on an unfractured fracture zone of the earthquake-generating structure; determining a seismic increase and decrease analysis function according to the fracture half length and the position relation; the independent variable of the seismic increase and decrease analysis function is the ratio of the distance of any point relative to the seismic source of the seismic structure to the fracture half length, and the dependent variable of the seismic increase and decrease analysis function i