Earth is cooling faster than previously thought

Since its formation 4.5 billion years ago, The earth continues to heat up, So cool. This Heat Mainly comes from radioactive decay of components of various earth envelopes. The other three energy sources Can be cited: Progressive crystallization of the outer center, The Movements Gravity Minerals Crystallizes within the nucleus Liquid, And thisEnergy Earth’s inner waves. The assembly generates a significant heat flux, which is essential for production Convection Mandelick, here Lays the foundation for the tectonic and volcanic activity of our planet. It can be said that this heat flow is what makes the earth geographically alive. However, this heat flow will not last forever.

As the Earth cools, it gradually reduces its internal heat distribution. The day will come when the heat flow will not be sufficient to support the convection in the mantle (even if it is very far away). At that point, Earth will become a “dead” planet, and plate tectonics will cease. While this very long-term development is beyond doubt, it is difficult to quantify. Because at the moment we do not know exactly Speed How long does it take for the earth to cool or deplete its reserves.

Bridgestone is a more conductive mineral than previously thought

To answer these questions, it is necessary to understand how heat dissipates into the earth, including the surface emitted by volcanic activity. One of the main areas appears to be the interface between the outer center Code. In fact, it is at this level that the liquid crystal porridge of the outer core is formed Do And Nickel, Is in direct contact with the rocks of the mantle. The Gradient Between these two stages is very high and the heat flux is very high. In this interface, the mantle is mainly composed Of a mineral called bridgezmonite. Knowing the heat transfer capacity of this mineral will help to better understand the cooling rate of the earth. A team of researchers from ETH Zurich and the Carnegie Institute in Zurich have recreated conditions in the laboratory at the level of the core / mantle interface to measure the radioactive thermal conductivity of bridge bridges at the base level. Inferior.

The results show that the average thermal conductivity at the core / mantle interface is 1.5 times higher than previously estimated. This new value suggests that the heat flux from the center may be higher than previously thought. Reassessment of heat flow has two effects. First, the convection in the formed mantle must be stronger than expected. As a result, the mantle cools more efficiently, so it will be faster than previous designs.

Towards the acceleration of the Earth’s cooling

This new data may have implications Duration Life of some tectonic functions driven by mantle convection. Rapid cooling of the mantle, especially at the core / mantle interface, can lead to changes in mineral levels. In fact, when Bridgmanite cools, it becomes a new mineral, the latter Perovskite. However, this ore conducts heat much more efficiently than bridzmanite. Thus, as the Earth cools, it becomes the dominant mineral at the base of the post-Perovskite crust, accelerating the transfer of heat toward the surface, thus accelerating cooling.

Results of the study published in Letters from Earth and Planetary Science Thus opening up new perspectives on the evolution of the Earth’s dynamics. Tuesday and Mercury, The earth will decompose much faster than we thought. But if we do not know how long it will take, plate tectonics still has a good life.