The auxiliary S-transform
Adewale Amosu, Yuefeng Sun · 2021
The traditional S-transform combines the advantages of the Short Time Fourier Transform and wavelet transform by making use of a frequency-dependent Gaussian window, however, its resolution may still be inadequate for certain seismic interpretation applications. Coherency-based spectral decomposition methods rely on multi-trace coherency attributes to improve spectral decomposition results. We propose a new coherency-based spectral decomposition method, the Auxiliary S-transform, which significantly improves on the resolution of the S-transform. The Auxiliary S-transform maps a seismic section into the time-frequency-slowness domain where the properties of coherent seismic signals are more easily accessible and coherency information can be harnessed. In this domain, the most coherent signals are better resolved using a percentile coherency filter obtained from the slant-stack transform. We apply the Auxiliary S-transform to synthetic and real seismic data and evaluate its performance. Compared to the S-transform, the Auxiliary S-transform demonstrates improved temporal resolution at all frequencies.