A critical tectonic process between the core and surface layers may be shut down earlier than anticipated

The Earth's molten interior is cooling faster than expected, which could turn the planet into a cold, inactive world similar to neighboring Mercury and Mars sooner than previously thought, researchers have warned.

The study, published in the Earth and Planetary Science Letters journal, examined how well bridgmanite – the primary mineral found at the boundary between the planet's core and mantle layers – conducts heat from the hot, molten core to the surface.

Researchers irradiated a bridgmanite crystal with pulsed lasers on a diamond anvil press to simulate the effects of intense heat and pressure at the boundary. They found that the rate at which the mineral conducted heat was "about 1.5 times higher than assumed."

The findings mean that the cooling of the Earth's core is speeding up, and it is "becoming inactive much faster than expected."

The rapid cooling could, in turn, lead to an earlier slowing-down of processes like plate tectonics, which are related to the movements of large underground slabs composed of the crust and outer mantle layer and volcanic activity.

This heat exchange from the planet's core helps generate the Earth's magnetic field, which is understood to be protecting the planet's atmosphere from solar radiation and allow life to thrive.