Numerical Algorithm of the Coupling Ray Theory in Weakly Anisotropic Media

The paper is devoted to the numerical calculation of the frequency-dependent complex-valued vectorial amplitudes of S waves in weakly anisotropic media by the coupling ray theory. An efficient and accurate method of numerical integration of the coupling equation is proposed, and the accuracy of the method is estimated in order to control the integration step so that the relative error in the wavefield amplitudes due to the integration is kept below a given limit. Several quasi-isotropic approximations of the coupling ray theory are briefly discussed and a numerical example is presented.