How to separate ground waves from casing waves by time-frequency analysis

1, acquisition of seismic data and preprocessing, including the removal of noise, weakening the conventional components, etc..

2, Fourier transform the preprocessed seismic data into the form of spectral distribution.

3, the time-frequency analysis of the spectral distribution, the specific method can choose the classical time-frequency analysis method, such as Gabor wavelet transform, wavelet packet transform, short-time FT and so on.

4, after the time-frequency analysis, waveform separation by detecting certain eigenvalues, such as the maximum principal frequency, signal power, entropy, autocorrelation function, cross-correlation function and other eigenvalues.

5. Finally, the separation of casing waves and ground waves in the time domain can be obtained by transforming the coordinates of the seismic signal on the time axis.