An ancient sunken ocean floor seems to lie above Earth’s core, under the mantle

Source: The post is based on the article “An ancient sunken ocean floor seems to lie above Earth’s core, under the mantle” published in Indian Express on 15th April 2023

What is the News?

Geologists have discovered a new layer between the core and the mantle that is likely to be a thin but dense sunken ocean floor.

What have the geologists discovered?

Earth’s structure was divided into four layers: crust, mantle, outer core, and inner core.

Now a fifth layer has been discovered which is between the core and the mantle that is likely to be a sunken ocean floor seen only in isolated patches previously.

This layer is pencil-thin in geological terms, measuring tens of kilometres, which is minuscule when compared to the thickness of Earth’s other layers.

This layer can be thought of as mountains along the core-mantle boundary, with heights ranging from less than about three miles to more than 25 miles.

What is the significance of this discovery?

Firstly, the analysis could reveal how this layer plays a role in heat to escape from the core, the portion of the planet that powers the magnetic field.

Secondly, this new discovery opens up new avenues of research for geologists and could lead to a better understanding of Earth’s geological processes.

Thirdly, the detailed method used to probe a large portion of the Southern Hemisphere using sound wave echoes from the core-mantle boundary could be used in other parts of the world to uncover similar anomalies.