The present application belongs to the technical field of oil
seismic exploration, and discloses a near-surface modeling method and
system based on microseismic
spectral ratio interface imaging constraint, wherein the method comprises the following steps: collecting continuous microseismic data of a set time length in the whole work area and performing pretreatment; performing
spectral ratio calculation on the pretreated microseismic data,
smoothing the
spectral ratio, and obtaining peak frequency from the smoothed spectral ratio; obtaining the shear
wave velocity structure from the microseismic
signal inversion, converting the peak frequency under each
station into interface depth according to the shear
wave velocity structure, and obtaining the interface depth information of the whole work area; taking the interface depth information as a constraint condition, adding the first arrival wave
travel time tomography inversion, and completing the near-
surface velocity modeling. The present application provides fine
lithology interface constraint, makes up for the defect of insufficient micro-
logging spatial sampling, improves the vertical resolution and lateral continuity of the near-
surface velocity model, and solves the problem of insufficient accuracy of the near-surface model caused by lack of constraint in complex areas.