Thermal Evolution for the Moon.
(left: Temperature; right: Composition)
In this model, C=0.15 and Hic/Hb=20; Ri = 200 km; Ric = 560 km; T-dependent
viscosity with minimum viscosity 1e19 Pas and activation energy 150 KJ/mol;
The first phase of instability happens within the IC at about 320 Ma
with maximum T of 1682 C. The second phase of instability with longer
wavelength happens at about 400 Ma with max T of 1712 C.
Thermal expansivity for the liquid phase is 8x10^-5 /K;
density difference for the liquid ilmenite is reduced by half.