Low-frequency model establishment method and device based on time-frequency analysis

The invention relates to a low-frequency model establishment method and device based on time-frequency analysis. The method comprises the following steps: respectively extracting seismic trace data and a velocity curve corresponding to each to-be-calculated point from a seismic data body and a seismic velocity body; for each to-be-calculated point, determining a time-frequency spectrum corresponding to the seismic trace data based on short-time Fourier transform; determining an earthquake cycle curve based on the time-frequency spectrum; determining an impedance low-frequency curve based on the velocity curve; determining a low-frequency model curve according to the earthquake cycle curve and the impedance low-frequency curve; and determining a low-frequency model according to the low-frequency model curve corresponding to each calculation point. According to the method, the sedimentary cycle information contained in the seismic trace data can be fully utilized, the low-frequency model which is better in prec