Radial profiles of the surface density in simulation C4 rescaled around Jupiter’s position. The teal line corresponds to a time when only Jupiter and Saturn are in the disc (essentially the simulation from Griveaud et al. 2023). At that time, t = 142 kyr, the pair of planets is migrating slowly inwards, as seen in Fig. 5. The magenta line shows the profile when the four giant planets are migrating outwards at t = 308 kyr. The planet positons are given by the circle markers. The vertical dotted lines indicate the positions of the inner Lindblad resonances (ILR) of Jupiter and the outer Lindblad resonance (OLR) of Saturn (see text for more details).