Extended Data Fig. 5. Geodynamic models of a 410-km-deep model domain.

Frames from simulations showing different stages in the model evolution from 30 Myr before break-up (a) to 50 Myr after break-up (e). The depth of the model domain of 410 km was chosen to avoid complexities of the phase changes in the mantle transition zone. This model shows that sequential delamination occurs independent of the depth of the model domain. Instability migration velocity in this run varies slightly more than in the shallower scenario but averages 15–20 km Myr⁻¹, identical to the reference model (see Fig. 2). Compared with the reference model (300 km deep), the 410-km model exhibits convection cells roughly twice as high; however, at the depth of the metasomatized layer, the horizontal distance between instabilities is very similar (about 250 km).