Abstract:In the method for producing some instantaneous characteristic signals by using Hilbert transform,Hilbert transform is very sensitive to high-frequency random noise. As a result,even though there exist weak high-frequency noises in seismic ignals,the obtained instantaneous characteristics of seismic signals may be still submerged by the noises.One method for having instantaneous characteristics of seismic signals in wavelet domain is put forward,which obtains directly the instantaneous characteristics of seismic signals by taking the characteristics of both the real part (real signals,namely seismic signals) and the imaginary part (the Hilbert transform of real signals) of wavelet transform. The method has the functions of frequency division an noise removal. What is more,the weak wave whose frequency is lower than that of high-frequency random noise is retained in the obtained instantaneous clZaracteristics of seismic signals,and the weak wave may be seen in instantaneous characteristic sections(such as instantaneous frequency,instantaneous phase and in-stantaneous amplitude).