Time-distance plots along Path1 (magenta), Path2 (green), and Path3 (blue) for different density profiles of the incoming wave and different CH geometries. The blue and green regions denote areas in which the density is lower than the background density (depletion), and the red and orange regions denote areas in which the density is higher than the background density (enhancement). The horizontal dark blue regions denote the CH area. (a)–(c): Time-distance plots of an incoming wave that only consists of an enhancement without a depletion in the rear part of the wave that interacts with a circular CH. (d)–(f): Time-distance plots of an incoming wave with a density profile consisting of an enhancement at the wave front and a depletion area in the rear part of the wave that interacts with a circular CH. (g)–(i): Time-distance plots of a full density profile (enhancement + depletion) that interacts with an elliptic CH and a CH density of ρ_CH = 0.1.