Logarithmic decrements and other functions of seismic wave attenuation
© D.N. Grin, 2001
We propose an algorithm of the estimation of the logarithmic decrements of attenuation (LDA) on the basis of the seismic trace decomposition according to basic functions (narrow-band components) and the calculation of their envelopes using Gilbert transformation. Each envelope contains (at a respective mean frequency in a narrow band) information on the attenuation functions. Using the envelopes one makes a root-mean-square estimation of LDA at each discrete time moment so that the dimension of the section coincides with that of the input data. We present algorithms and calculations of other functions of attenuation according to spectra and minimal-phase elementary signals: absorption coefficients spectra, phase velocities, high quality, relaxation time and LDA for comparing.