The mysterious third element of the Earth’s core that scientists believe to have identified
This study suggests that silicon exists in the inner core of the Earth, along with iron and nickel.
The third element of the Earth’s core was a mystery.
For decades, scientists have been trying to establish which component is a significant part of the center of our planet, along with iron and nickel.
But some Japanese scientists believe they have discovered what it is about.
Recreating the high temperatures and pressures found in the Earth’s core, experts have concluded that the most likely candidate is silicon.
“About 5% of the weight (of the inner core of the Earth) could be silicon dissolved in iron and nickel alloys,” said Eiji Ohtani, a principal investigator at the University of Tokyo, Japan. “We believe that silicon is an important element. , To the BBC.
The finding could help us better understand how our planet formed.
Hard to reach
It is believed that the core of our Earth is a solid ball with a radius of about 1,200 km.
How do we know what is in the center of the Earth?
As it is too deep, scientists can not investigate directly. To study their composition, they observe how seismic waves travel through this region.
The core consists mainly of iron, which is an estimated 85% of its weight, and nickel, which represents approximately 10%.
The remaining 5% had to be identified.
Seismic waves help you understand the composition of Earth’s core.
To find out, Eiji Ohtani and his team created iron and nickel alloys, and mixed them with silicon.
Then they were subjected to the immense pressures and temperatures that exist in the core of the Earth.
They found that, with seismic effects, this mixture behaved just like what was seen in the interior of the planet.
Professor Ohtani said that more work is needed to confirm that the third element is actually silicon and that it did not rule out the presence of other components.
Professor Simon Redfern of the University of Cambridge in the United Kingdom said that “these difficult experiments are really exciting because they can provide a window into what the interior of the Earth was like shortly after its formation, 4,500 million years ago, When the nucleus began to separate from the rocky parts of the Earth. ”
“Other researchers have recently suggested that oxygen could also be important in the nucleus,” he added.
He said that knowing what exists in that part could help scientists better understand the conditions that prevailed during the formation of the Earth.
Specifically, it could serve to determine whether oxygen was limited or abundant.
Silicon is used to make products such as solar panel cells.
If more than 4,000 million years ago there had been more silicon in the Earth’s core, as the results of the Japanese Ohtani suggest, that would have left the rest of the planet relatively rich in oxygen.
But if, on the other hand, oxygen had been sucked into the nucleus, the rocky mantle around the nucleus would have run out of this gas.
A new journey to the center of the Earth to understand its core
“In a way, these two options are real alternatives that depend very much on the prevailing conditions when the Earth’s core began to form,” said Professor Redfern.
“The latest results contribute to our understanding, but I suspect they are not the last word,” he added.
Professor Ohtani presented his research at the meeting of the American Geophysical Union in San Francisco, California, in December 2016.