Passive source multi-mode surface wave frequency dispersion curve extraction method based on array

The invention discloses a passive source multi-mode surface wave frequency dispersion curve extraction method based on an array. The method comprises the following steps: dividing a dense station array into a secondary station array; calculating a station-to-noise cross-correlation function of the secondary station array; constructing a cross-spectral density matrix according to the station-to-noise cross-correlation function of the secondary station array; according to the cross-spectral density matrix, determining a frequency dispersion diagram by using a weighted cross-correlation beam forming method or a modified cross-correlation beam forming method; and extracting a multi-mode surface wave frequency dispersion curve according to the frequency dispersion diagram. According to the method, background noise data of a station array is utilized, a multi-mode surface wave frequency dispersion curve with enough precision is extracted through short recording time, non-uniqueness of inversion is reduced during in