Fig. 1. Shear wave fast direction and delay for SKS waves received at a hypothetical station from a variety of directions and apparent velocities (in km/s). Data are shown as a bar centered on the nominal backazimuth and apparent velocity, with the bar's orientation parallel to the azimuth of the the fast direction, and its length proportional to the delay. Near-zero delays are plotted with open circles. (Left) For an earth model with a single single hexagonally-anisotriopic layer with horizontal symmetry axis overlying an isotropic halfspace; (Right) For a model where the symmetry axis dips by 45 degrees. Note that the splitting parameters vary most slowly in the horizontal case. (Postscript version)