Recent Spectral Decomposition Techniques and Its Applicationsin Analysis of Seismological Data: A Review

The Spectral decomposition of seismic data was incepted earlier in the second half of the 19th century, howeverlimited research work has been done in this filed because of lack of availability of advancetools/ techniques for analysis of transient signal like earthquake time historyrecords. Although, there are several conventional techniques like Fourier Transform (FT),Fourier Series (FS)that are available and used for analysis and processing in seismic data. FT decomposes the signal into its constituent frequency components. Butit‟s simple interpretation of pure frequencies, it is not always the suitable tool to analyse the non-stationary signals.FT can identify the frequencies that are present in signal but does not reveal where changes in the frequency contents occur i.e., no temporal information of frequencies. Consequently,for the proper interpretation of seismic data in terms of varying frequency content, we needtimefrequency representation techniques jointly. This paper reviews the linear and quadratic time-frequency representations techniques and their applications in analysis and processing of seismic data.