Minimum number of azimuth sectors for seismic anisotropy estimation

In this paper we present a practical extension of earlier work on the estimation of anisotropy parameters from isotropic techniques. We will take a closer look at the implications of working with effective elastic parameters in anisotropic (TI) seismic reflection inversion. In particular, for HTI media, the magnitude of the azimuthal Fourier terms is assessed. For many natural rocks the harmonic equations describing effective HTI anisotropy can be simplified, allowing for faster and more cost effective estimation of the magnitude and orientation of the anisotropy. Limits to these approximations in terms of the number of input azimuthal sectors used in the estimations are discussed.