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Scientists have identified a doughnut-shaped zone at the top of the Earth’s outer core.
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This light region aids in agitating the liquid metal, thereby producing the magnetic field.
Researchers have discovered a gigantic donut-shaped formation lying hidden deep within the Earth’s crust, stretching thousands of miles downward.
To gaze into the enigma of the Earth’s burning nucleus.
By following the path of these waves through the planet, the researchers discovered a region approximately several hundred kilometers thick where they moved about two percent slower than usual.
A donut-shaped structure located at the outer edge of the liquid outer core extends along the equator and plays a crucial role in generating the Earth’s protective magnetic field.
Professor Hrvoje Tkalčić, lead author of the study, says: ‘The magnetic field is a crucial element for life to be maintained on the surface of our planet.’
The outer shell of the Earth is made up of its surface crust. Beneath that lies the semi-molten mantle. Further down, there is a liquid metal in its outer core. At the center of the Earth, there is its solid metal inner core.
When the movement of tectonic plates within the Earth’s crust triggers earthquakes, these release vibrations that spread through all the other layers of the Earth.
Researchers can observe how the waves propagate and make projections about the conditions beneath the surface.
Scientists typically focus on the large and powerful shockwaves that traverse the globe in the initial sixty minutes following an earthquake.
However, Professor Tkalčić and his co-author Dr. Xiaolong Ma were able to detect this structure by examining the faint footprints left behind by waves many hours after the initial earthquake.
This method showed that seismic waves moving near the polar regions were travelling faster than those close to the equator.
According to a study led by Professor Tkalčić and Dr Ma, the findings suggest that the Earth’s mantle is best described by the presence of a massive, doughnut-shaped formation beneath its surface.
They forecast this area exists near the tropics and extends parallel to the equatorial line near the upper boundary of the outer core, where liquid silicon meets the mantle.
We don’t know the exact thickness of the crust, but we estimated that it extends a few hundred kilometers below the core-mantle boundary,’ Professor Tkalčić says.
Their finding’s significance may have far-reaching impacts on the study of life on Earth and other planets mainly due to this area’s crucial role.
The Earth’s outer core has a diameter of approximately 4,320 miles (6,960km) in circumference – slightly larger than that of Mars.
Comprising primarily of hot nickel and iron, convection currents that take advantage of the Earth’s rotational force push liquid metal in this layer to form long vertical vortices extending in a north-south direction, resembling colossal whirlpools.
It is the swirling streams of these liquid metals that function like a dynamo, energizing the Earth’s magnetic field.
Since this donut-shaped region has layered itself on top of the liquid outer core, it implies that it could be enriched in lighter elements like silicon, sulfur, oxygen, hydrogen or carbon.
The professor says: “Our research reveals this compelling phenomenon where the liquid core’s low velocity signifies the presence of a high concentration of lightweight chemical elements, which in turn causes seismic waves to slow down.”
‘It’s the lighter elements combined with temperature differences that cause the liquid to circulate in the outer core.’
The Earth’s magnetic field is believed to have emerged due to the internal stirring motion of the planet, without which it could have remained without a magnetic field.
from the sun which can destroy the DNA of living creatures.
This donut-shaped region, therefore, might be a critical piece of the puzzle which explains why life has developed on Earth and what we might look for in habitable planets elsewhere.
Dr. Tkalčić concludes: “Our findings can inspire more research on the magnetic field on both Earth and other planets.”
