Between the core and the mantle of the Earth there is a “vast structure, made of dense material”, whose existence was not known previously, was discovered by a group of scientists from the University of Maryland (USA).
The discovery was made thanks to a research on the behavior of seismic waves. The team used the same algorithm is applied to analyze distant galaxies, according to an article published in the journal Science.
The structure discovered beneath the Marquesas islands in the South Pacific, which are of volcanic type. In addition, it was demonstrated that the structure beneath these hawaiian islands is much larger than previously believed.
The researchers do not yet know of what is composed this finding, but point out that “provides the opportunity to better understand the intricate processes that have allowed our planet to evolve and change with the time”.
“By observing thousands of echoes from the boundary of the mantle and core at the same time, instead of focusing on a few at a time, as is usually done, we have obtained a totally new perspective“said Doyeon Kim, a postdoctoral fellow in the Department of Geology and lead author of the article.
According to the scientist, his study shows that the boundary region of the core-mantle has many structures that can produce these echoes. His team measured the travel time and amplitude of the echoes generated by the seismic waves after an earthquake. Thanks to these calculations, the researchers developed models of the physical properties of the rocks hidden beneath the surface, among other things. (I)