Determination of anelastic reflectivity: how to extract seismic AVF information

Christopher W. Bird, Kristopher A. Innanen, Laurence R. Lines, Mostafa Naghizadeh

Strongly dispersive reflection coefficients associated with highly absorptive, hydrocarbon charged targets, have been observed in seismic data. A frequency by frequency method (AVF) for determining Q of a highly absorptive target from measurements of the dispersive reflection coefficient is reviewed in this paper. In order to implement the AVF technique to invert for Q, it is necessary that we have a method of estimating the local spectrum of the reflection coefficient. We develop a method of implementing AVF inversion by using a calibrated, fast, non-redundant S-transform (FST) algorithm to estimate the local spectrum of dispersive reflection coefficients. We test the effectiveness of the FST for estimating the spectrum of reflection coefficients by comparing with the analytic reflection coefficient as calculated by a fast Fourier transform. Using forward modeling to generate synthetic traces for a single absorptive reflection coefficient we observe accurate results of the AVF inversion, using the FST, for a range of Q values.