Scientists find giant 600-mile wide 'megastructures' buried deep below Earth's surface

prof.Abdelhamid Fouda 

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The mysterious 'ultra-low velocity zones' were detected by researchers looking at data from earthquakes, and date back to the period before the Earth had a Moon.


Geologists have discovered mysterious giant structures hidden deep within the Earth.

We know less about the interior of the Earth than we do about the surface of the Moon.

No-one, not even a robot probe, has ventured deeper than a few miles into the Earth's crust.

Now data from hundreds of major earthquakes has helped a team led by Doyeon Kim at the University of Maryland in the US discover a strange new structure beneath the Marquesas Islands in the South Pacific Ocean.

The structure, known as an ultra-low velocity zone (ULVZ), is about 620 miles in diameter and just under 16 kilometres thick, says Kim.

A similar, even larger structure exists beneath Hawaii.

While we know that motion at the core of the Earth generates the magnetic field that protects us from deadly solar radiation, the science behind how this field is generated is not fully understood.

Even the theory of plate tectonics – the mechanism behind continental drift that causes earthquakes and volcanoes – was not generally accepted until after the First World War.

These gigantic and mysterious structures are especially interesting because they date back to the period before Earth had a Moon.

These chunks of exotic material could even be the scars dating back to the titanic collision between the Earth and an unknown object the size of Mars that gave birth to the Moon over four billion years ago.

The intriguing anomalies deep within the Earth are revealed by the progress of seismic waves caused by earthquakes.

Kim’s team analysed seismograms produced by slow-moving shear (S) waves that follow earthquakes’ primary tremors (P-waves) along the boundary between the Earth’s mantle and its core.

These S-waves produce clearer signals for analysis.

Kim’s team used an algorithm called Sequencer to process the data from hundreds of earthquakes that occurred between 1990 to 2018.

The data offers unique insights into the deepest and oldest parts of our planet.