Scientists find 3.3 billion-year-old crustal fragments

Our world may seem extremely fragile, especially in the face of the climate crisis. However, the Earth has existed for a very long time – our planet is over 4.5 billion years old. For centuries, scientists have been trying to look into the Earth's past to understand what it looked like when it was very young. Про це розповідає SSPDaily.

Science Alert writes about this.

According to scientists, the answer lies in some of the earliest large remnants of the earth's surface found in a remote corner of the highlands of southern Africa, a region known to geologists as the Barberton Greenstone Belt.

For a long time, scientists have been trying to decipher the geological formations found here. A new study has changed everything. It has shown that the key to unlocking this code lies in geologically young rocks that lie on the seabed off the coast of New Zealand.

This has opened up a new perspective on what our planet looked like when it was young.

The work began with the creation of a new detailed geological map of a part of the Barberton Greenstone Belt. As a result, a fragment of the ancient deep seabed formed about 3.3 billion years ago was discovered, says the team of scientists from Victoria University of Wellington.

However, there was something very strange about this seafloor, and it took a study of rocks lying in New Zealand to figure out what it was.

The authors of the paper state that the early Earth was not an extremely hot and earthquake-free place with a weak surface, unable to form solid plates.

Instead, the young Earth was constantly shaken by strong earthquakes caused by one tectonic plate sliding under another in a subduction zone within plate tectonics – just like modern-day New Zealand.

Layers that formed on land or in shallow water – for example, beautiful barite crystals that crystallized as evaporites or the remains of seething mud pools – are on top of rocks that have accumulated on the seafloor. Blocks of volcanic rock, flint, sandstone, and conglomerate lying upside down and mixed.

The bedrock here is a mixture of sedimentary rocks originally laid down on the seabed off the coast of New Zealand about 20 million years ago. This region is located on the edges of a deep ocean trench where the Pacific tectonic plate slides down in a subduction zone, causing frequent strong earthquakes. Scientists now insist that it is the stones from this area that hold the key to unraveling the "Barberton Greenstone Belt geologic data."

"What was previously thought to be mysterious and 'unreadable' turned out to be the remains of a giant landslide containing sediments from both land and shallow water mixed with sediments that had accumulated on the deep seabed," the scientists say.

These fragments provide clues to the origin of the world and its formation as we know it today.