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EXPLORE FURTHER: The Enigma of Over 100 Quakes That Hit Surrey
is solved
From Atlantis to El Dorado and Avalon, legends suggest that our planet is scattered with vanished realms that suffered spectacular fates.
Although these are often regarded as creative legends, recent research uncovers proof of a ‘vanished realm’ under the Pacific Ocean.
Researchers from ETH Zurich and the
California
The Institute of Technology (Caltech) has discovered massive formations deep under the Pacific Ocean that theoretically shouldn’t be there.
This mystery material – which is making seismic waves in the region behave strangely – could be evidence of a lost land from hundreds of millions of years ago.
Based on present scientific theories, the unusual material located in the lower mantle, approximately 600 miles (1,000 km) under the ocean surface, ‘ought not to be present’ there.
Referred to as a significant enigma, these discoveries challenge ‘our present comprehension of how our planet functions,’ stated the scientists involved.
“The team, in their paper published in various journals, emphasize that understanding Earth’s structure is crucial for deciphering its internal movements,” they state.
Scientific Reports
.
These discoveries indicate a greater variety of sources for these irregularities in Earth’s lower mantle.
The Earth consists of three layers: the crust, the mantle, and the core, as identified subsequently.
divided into ‘internal’ and ‘external’ parts
.
The issue is that nobody can observe what lies beneath the Earth’s surface, and drilling deep enough to collect rock samples from the mantle is impossible for us.
Rather than directly observing Earth’s insides, researchers examine the velocities of seismic waves – the tremors triggered by quakes and blasts – as these waves move through our planet’s depths.
Seismograph stations capture these waves, and from these records, experts can deduce information regarding the Earth’s structure and makeup.
‘ETH Zurich explained that this process closely resembles how medical professionals utilize ultrasound technology to visualize internal structures such as organs, muscles, or blood vessels within the body without requiring surgical intervention.’
It is widely recognized that Earth’s lithosphere—the rocky exterior layer consisting of the upper part of the mantle and the crust—is made up of approximately 15 tectonic plates.
Earthquakes can be identified around the edges of tectonic plates, where these massive sections grind against one another.
However, long ago, substantial tectonic plates vanished beneath Earth’s surface through a process known as ‘subduction.’
This is the geological process where one tectonic plate gets thrust beneath another, and gradually, an entire plate can disappear.
Previously, seismologists have located submerged tectonic plates across the Earth’s mantle, though these were consistently found beneath subduction zones.
In their latest research, scientists from ETH Zurich and Caltech employed a computational method known as ‘full-waveform inversion.’ This approach generates a three-dimensional representation of the Earth’s structure utilizing seismic wave information.
They pinpointed regions beneath the Pacific that appear to be remnants of sunken tectonic plates, yet these zones are situated far from plate edges without any geologic signs of previous subduction activity.
The Pacific Plate is essentially one single tectonic plate, which means there shouldn’t be any subducting material beneath it at all.
This implies that the anomalies are not simply submerged tectonic plates. Nevertheless, identifying the actual nature of this material—or understanding its implications for the dynamic processes within the Earth—remains a mystery.
“It’s akin to a physician who has spent years using ultrasounds to examine blood flow and discovers arteries precisely where they should be,” stated co-author Professor Andreas Fichtner, a seismologist at ETH Zurich.
‘If you provide him with a more advanced examination tool, he abruptly detects an artery in the buttocks that shouldn’t actually be present. This precisely mirrors our reaction to these new discoveries.’
Nevertheless, the researchers offer several hypotheses regarding the anomalies, suggesting that these would require additional data beyond just wave speeds to draw any firm conclusions.
These might consist of ancient, high-silica substances that have remained within the mantle from its inception around four billion years ago.
Instead, these areas might be regions where iron-rich rocks gather due to mantle activity spanning millions of years.
They state in their paper, “There are various possible interpretations for the observation of positive wave speed anomalies within Earth’s (lower) mantle besides the existence of subducted slabs.”
‘Our study highlights the essential function of full waveform inversion as a crucial technique for exploring the mantle.’
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