Scientists have found two huge “islands” hidden deep within the Earth’s mantle.
They say these islands are larger than a continent and at least half-a-billion years old.
Utrecht University research, published in Nature, says these underground regions are hotter than the “surrounding graveyard of cold sunken tectonic plates”.
“These observations contradict the idea of a well-mixed and fast flowing Earth’s mantle, a theory that is becoming more and more questioned,” the research report said.
“There is less flow in Earth’s mantle than is commonly thought.”
Seismologists study Earth’s deep interior by monitoring tones inside the planet and assessing if they are “out of tune” due to anomalies.
“An analysis of these oscillations showed the existence of two subsurface ‘super-continents’: one under Africa and the other one under the Pacific Ocean, both hidden more than two thousand kilometres below the Earth’s surface,” the report said.
“Nobody knew what they were, and whether they are only a temporary phenomenon, or if they have been sitting there for millions or perhaps even billions of years.”
The new research backs the view that these areas are ancient and very different to tectonic plates in the same region.
