Extended Data Fig. 8: Protokeel formation in the reference model after switching off the prescribed plate convergence.
From: Building cratonic keels in Precambrian plate tectonics
The reference model is described in Fig. 1: Tp = 1,500 °C, ΔT = 200 °C. a–d, Slab-pull controlled retreating subduction and slab break-off of the oceanic plate with highly depleted mantle. Prescribed convergence is switched off at 4.8 Myr after the beginning of the experiment; e–h, Building of the mantle protokeel during slab-pull controlled retreating subduction and slab break-off of the oceanic plate with highly depleted mantle after switching of the prescribed convergence at 8.4 Myr from the beginning of the experiment. Dotted lines indicate boundaries of the mantle transition zone. We note the reduced volume of the protokeel in h (see Fig. 1d). The colour-code is shown in Fig. 1. Protokeel source mantle (T >1,300 °C, melt depletion >20%) under subducting plate is outlined by magenta colour for better visibility.
