Researchers at ETH Zurich have demonstrated in the lab how well a mineral common at the boundary between the Earth’s core and mantle conducts heat.

However, the enormous thermal energy emanating from the Earth’s interior set dynamic processes in motion, such as mantle convection, plate tectonics, and volcanism.

This boundary layer is relevant because it is here that the viscous rock of the Earth’s mantle is in direct contact with the hot iron-nickel melt of the planet’s outer core.

This may cause plate tectonics, which is kept going by the convective motions of the mantle, to decelerate faster than researchers were expecting based on previous heat conduction values.

But as soon as post-perovskite appears at the core-mantle boundary and begins to dominate, the Cooling of the mantle might indeed accelerate even further, the researchers estimate, since this mineral conducts heat even more efficiently than bridgmanite.

Moreover, scientists need to clarify how the decay of radioactive elements in the Earth’s interior – one of the main sources of heat – affects the dynamics of the mantle.