Fig. 2From: Subduction initiation from a stagnant lid and global overturn: new insights from numerical models with a free surfaceRadial parameter profiles of regional models. Radial profiles of experiments with a no yielding, b depth-dependent yielding, c depth-constant yielding and d composite yielding with a transition at 50 km depth. Shown in each subplot are temperature (left), viscosity (middle) and second invariant of stress (right) for both regional models with either a free-slip surface (grey) or a free surface (orange)Back to article page