Thanks to a new technique for reading seismic waves, a team of geologists from the universities of Illinois (USA) and Nanjing (China) has discovered that there is a second core within the core of the Earth . The finding has been published in the journal Nature Geosciences .
The scientists used seismic waves from earthquakes and “scanned” what is below the surface using technology that obtains data from the waves that resonate in an earthquake , sort of like the “coda” signal of an earthquake.
“Although the Earth’s core is small, smaller than the Moon, it has some very interesting characteristics that can tell us how our planet came to be, what its history was like, and how the various dynamic processes on Earth take place. What happens in the core shapes our understanding of what happens deep within the Earth, ”explains Xiaodong Song, leader of the study.
And it is that looking through the Earth’s core revealed the presence of a “nucleus within the nucleus”, perfectly defined and with about half the diameter of the complete nucleus. According to the readings, the iron crystals in the outer layer of the Earth’s core are directionally aligned, from north to south; however, the crystals of this newly discovered second core are aligned from east to west .
The behavior of both nuclei is also different, so experts believe that it could be made of a different material . “The fact that there are two regions that are so clearly distinguished may be telling us something about how the inner core of our planet is evolving. For example, throughout the planet’s history, the inner core could have had dramatic effects on the Earth’s deformation regime. And that could be the key to deciphering the evolution of our world. Now we are right in the center, literally, in the center of the Earth, ”clarifies Song.
