Top: Morphology of the density contrast field δ in the SGZ = 0 plane (red: overdensities; blue: underdensities). Bottom: Profiles of δ (red) and of the velocity magnitude $||\mathbf{v}||=\sqrt{v_x^2+v_y^2+v_z^2}$ (blue, in km s⁻¹) along the red dashed line shown in the top panel. The line is chosen arbitrarily and serves only to illustrate typical variations in the density and velocity fields.