Scientists have discovered a secret structure in the Earth’s core: textbooks may need to be rewritten



[ad_1]

“Traditionally we have been taught that our Earth has four main layers: the crust, the mantle, the outer and inner cores,” explained Joanne Stephenson, a geophysicist at the Australian National University, writes sciencealert.com.

Our knowledge of what lies beneath the earth’s crust is largely based on what volcanoes revealed and seismic waves whispered. Based on these indirect observations, the scientists calculated that the inner core incredibly hot, where the temperature exceeds 5 thousand. degrees Celsius, makes up only one percent of the Earth’s mass.

And now J. Stephenson and his colleagues have found more evidence that the Earth’s inner core probably consists of two separate layers.

“It’s extremely interesting and it could mean we’ll have to rewrite the textbooks!” He added.

This team of scientists used a special search algorithm to help analyze and combine thousands of inner core models with decades of observational data collected by the International Seismological Center on how long it takes for seismic waves to travel through the Earth.

So what’s down there? The team analyzed some models of anisotropy in the inner core, how differences in the structure of its constituent materials alter the properties of seismic waves, and found that some were more likely than others.

Research illustration

Research illustration

© Stephenson et al., Journal of Geophysical Research: Solid Earth, 2021

According to some models, the structure of the inner core allows seismic waves to transmit parallel to the equator, while others suggest that the composition of the materials allows the waves to propagate more rapidly parallel to the Earth’s axis of rotation. Even now, there is controversy over the exact difference between certain angles.

This study could not show large depth differences in the inner core, but the researchers were able to detect a slow direction deviation at a 54-degree angle. And the fastest direction of the waves is moving parallel to the axis.

“We have evidence to suggest that the structure of iron is changing, allowing us to talk about two separate cooling events in Earth’s history,” Stephenson said. “The details of this great event remain a mystery, but we have found another part of the puzzle that gives us more insight into the inner core of the earth.”

These new data may explain why some of the experimental data does not fit our current models of Earth’s structure.

The fact that there may be another “deeper layer” in the inner core has been suspected for some time, because the iron crystals that make up the inner core have a different structure.

“We are limited by receptor locations and global earthquakes, especially at the poles,” the team said, explaining that the lack of data reduces the reliability of their findings. However, their data is consistent with the findings of other recent studies on the anisotropy of the deeper inner core.

It is worth noting that a new approach is currently being developed that will help fill data gaps and allow scientists to gather or disprove the findings of others, which is expected to provide more information about this layer formed at the beginning of the study. history of the Earth.

It is strictly forbidden to use the information published by DELFI on other websites, in the media or elsewhere, or to distribute our material in any way without consent, and if consent has been obtained, it is necessary to indicate DELFI as the source.



[ad_2]