LONDON — Earth’s rocky plates are on the move. This process, known as plate tectonics, has shaped our planet’s features for billions of years. But when did this all start? That’s been a big question for scientists.
Recent research now hints that plate tectonics might have begun over 3.5 billion years ago, during the Archean Eon. This is groundbreaking because it suggests that tectonic activity was influencing Earth while early microbial life was already present.
Roger Fu, a professor of Earth and planetary sciences at Harvard University, led this study published in the journal Science. He emphasizes that understanding this timeline is crucial. “Why do you have mountains? Why do you have oceans? It only makes sense with plate tectonics,” he remarked.
Today, Earth has several major and minor plates, each about 80 miles thick, moving at a steady pace. Some scientists believe the process started around 4.4 billion years ago; others say it began within the last billion. The new research suggests a busy tectonic landscape existed far earlier than many thought.
Fu and his team studied rock samples from the East Pilbara Craton in Western Australia. This area is famous for fossils of early life, like stromatolites. Using paleomagnetism, a technique that examines magnetic minerals in rocks, they were able to understand how these ancient plates moved.
By analyzing 900 rock samples over a span of 30 million years, the team discovered significant shifts in the formation. They found that part of the region drifted from 53 degrees to 77 degrees latitude and rotated more than 90 degrees.
The findings challenge the idea that the Earth’s crust was a solid, unbroken shell. “It was segmented into different pieces that could move with respect to each other,” said Alec Brenner, a co-author of the study.
Importantly, this research offers high-quality data from some of the oldest rocks ever studied. Uwe Kirscher, a research fellow at Curtin University, calls it crucial evidence of how Earth transitioned to plate tectonics.
Understanding when plate tectonics started gives us a better glimpse into early Earth. It helps us see how life began and adapted to our planet’s changing landscape. This study not only redefines our timeline but also reinforces the ongoing conversation in the scientific community about our Earth’s dynamic history.
Source link
news,traffic,weather,sports,classifieds,cars,jobs,homes,television,radio,salt lake,utah,local,Science,Nature,History,Environment
