Scientists have made a groundbreaking discovery of long-lost remnants of tectonic plates sunken deep inside the Earth’s mantle. The plates were found lurking underneath the center of other continental plates, far from tectonic boundaries.
The finding is unexpected because previously, submerged plates had only been discovered in subduction zones. However, researchers used high-resolution modeling and various types of earthquake waves to uncover the secrets of the Earth’s interior.
According to Andreas Fichtner, a professor of seismology and wave physics at ETH Zurich, “This is like using a new method to examine arteries inside the body for many years suddenly gaining a brand new tool. You start seeing things that don’t belong there.”
The discovery was made in the western Pacific region, but no evidence of plate subduction was found. Researchers are unsure what the plates are made of or how they ended up in their current location.
“We think that the anomalies in the lower mantle have a variety of origins,” said Thomas Schouten, a doctoral student at the Geological Institute of ETH Zurich. “It could be ancient material that has been there since the Earth’s formation or zones where iron-rich rocks accumulate.”
To further understand the intricacies of the inside of the Earth, researchers plan to use even better models and calculate different material parameters behind wave speed.
The finding is baffling scientists and opens up new possibilities for understanding the Earth’s mantle.
Source: https://www.newsweek.com/tectonic-plate-hidden-earth-mantle-subduction-geophysics-mystery-2011515