Thermal inheritance in continental rifting.

While a lot of literature exist modelling the effect of former tectonic structure faults, stacking of different lithologies with a dip or former lacolithes, little has been done in modelling the effect of heterogeneous thermal properties in the lithosphere and particularly in the crust and these contributions are old enough that some of their main results need to be reminded and extended using current modelling tools.  

I will first recall how much periodic variations in heat production rate in the crust may affect the temperature at the Moho and the thickness of the lithosphere using analytical solution, I will then use thermo-mechanical simulation to demonstrate how important are these effects in 2 and 3D at tectonic timescale especially while reactivating former post orogenic collapse structures such as metamorphic core complexes and migmatite domes. I will illustrate how the simulation might apply to the West European rift, the Menderes massif or the South China Sea.

I will finally show using 2D numerical simulations how much the repartition of heat production in the crust influences the long-term survival of mobile belts and can explain partly why the European lithosphere keeps large heat flow despites its thermos-tectonic age.