Examining the interior of the planet is difficult for the most obvious reasons: the embryo begins at a depth of about 3,000 kilometers, and its temperature is 5-6 thousand degrees Celsius. ETH experts therefore simulated the layer between the core and the mantle under laboratory conditions.
This boundary layer is important because the viscous envelope here is in direct contact with the hot iron and nickel steel on the outside of the core. The temperature gradient between the two layers is very large, so there is a high heat flux here. The boundary layer consists mainly of a mineral called bridgezmonite (a very dense magnesium iron silicate).
Motohiro Murakami, a professor at ETH, and colleagues at the Carnegie Institute of Science have developed a sophisticated measurement system that allows the thermal conductivity of bridgesmann to be measured in a laboratory at the prevailing pressure and temperature in the depths of the earth.
“With this measurement method, we were able to show that the thermal conductivity of bridzmanite is one and a half times higher than previously thought,” Murakami said. From this it can be concluded that the heat flow from the center to the envelope is higher than previously thought.
This leads to blade tectonics, which is maintained by the thermal movements of the mantle, which weakens and slows down faster than previously thought.
“Our results shed new light on the dynamic dynamics of the Earth. Like other rocky planets like Mercury and Mars, the Earth is cooling and crashing faster than expected,” Murakami said.
Initial image: Rost-9D / Getty Images