Comparison of the tail velocity structure between models C10G13 (red lines) and C10W1 (blue lines) at 200 pc <  y <  300 pc. Upper left: velocity dispersion σ_x. Upper right: velocity dispersion σ_y. Lower left: velocity dispersion σ_z. The minima of velocity dispersions, as calculated from Eqs. (17), (18), and (4), are indicated by the black bars. Lower right: v_y component of the mean bulk tail velocity.