The discovery of strange underwater structures could reveal how life on Earth really began

Scientists think they’ve found a window into the dawn of time on Earth, and it’s hidden beneath the Pacific Ocean.

A team led by geophysicist Simon Lamb of the University of Wellington and scientist Cornel de Ronde of GNS Science said the key to our past lies in a remote corner of South Africa, far away on the seabed off the coast of New Zealand .

So what do these two sites, on opposite sides of the world, have in common?

Together, they shed light on a world still in its infancy, offering unexpected clues about the origins of the planet we know today – and possibly life itself.

To write for The conversationthe scientists explained that their work began after De Ronde created a new, detailed geological map of an area known as the Barberton Greenstone Belt, which lies in the highveld region of South Africa.

“The geological formations in this region are difficult to decipher despite many attempts,” the pair write.

They argue that the Belt’s bedrock does not match our then generally accepted understanding of plate tectonics.

But, they claim, their new research has provided “the key to cracking this code.”

Part of the Barberton Greenstone Belt in South Africa(International Geo-Heritage Commission)

De Ronde’s map revealed a fragment of ancient deep seafloor in the Barberton Greenstone Belt, formed some 3.3 billion years ago, when the world was only 1.2 billion years old.

“However, there was something very strange going on with this seabed,” write Lamb and de Ronde.

“And it took our study of rocks deposited in New Zealand, at the other end of Earth’s long history, to make sense of it.”

The two experts argue that the common understanding of the early Earth as a fiery ball of molten magma, whose surface was too weak to form rigid plates — and, by extension, undergo earthquakes — is wrong.

Instead, they propose that the young planet was continually rocked by large earthquakes caused whenever one tectonic plate slid beneath another in a subduction zone.

When they looked at Ronde’s map of the Barberton Greenstone Belt, they realized that the “jumbled” rock layers were reminiscent of more recent submarine landslides that have occurred in New Zealand.

These landslides were caused by large earthquakes along the country’s largest fault line, the megathrust in the Hikurangi subduction zone, where the bedrock is a mix of sedimentary rocks.

The Hikurangi Subduction Zone Projectwww.youtube.com

These rocks were originally deposited about twenty million years ago on the seabed off the coast of New Zealand, at the edges of a deep oceanic trench, where large earthquakes occurred regularly.

By considering the formation of this New Zealand bedrock, experts claim to have solved the mystery behind the Barberton Greenstone Belt formations.

Like its young successor, these structures were the “remnant of a gigantic landslide with sediments deposited both on land and in very shallow water, mixed with the sediments collected on the deep seafloor,” they conclude.

Simply put, if New Zealand’s rock layers were formed by earthquakes, then so were those in the Barberton Greenstone Belt – undermining the theory that the early Earth was not equipped to endure such tremors.

Furthermore, Lamb and de Ronde suggest that their work “may have unlocked other mysteries as well,” as they note, “Subduction zones have also been associated with explosive volcanic eruptions.”

They cite the example of the Hunga Tonga-Hunga Ha’apai volcano in Tonga, which erupted in January 2022 with the energy of a “60-megaton nuclear bomb” and sent a huge cloud of ash into space, creating a massive ash cloud over the next eleven hours. more than 200,000 lightning strikes flashed.

“In the same volcanic area, underwater volcanoes erupt an extremely rare type of lava called boninite. This is the most modern example of lava that was common on early Earth,” they add.

Ash clouds pierced with illumination resulting from the violent volcanic eruption of 2022(Tonga Geological Surveys via NOAA)

Lamb and de Ronde argue that the large amounts of volcanic ash found in the Barberton Greenstone Belt “could be an ancient record of similar volcanic violence.”

And, even more interesting, they suggest that the associated lightning strikes might have created “the crucible for life in which the fundamental organic molecules were forged.”

In other words, subduction zones are not only the source of tectonic chaos, they may also have been the spark that ignited the flame of life itself.

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