NASA’s latest view of our unique Earth from 1 million miles away, the only planet we know with active plate tectonics that was already moving 3.5 billion years ago. IMage Credit: NASA
It is fascinating how all these movements have been happening on Earth! This new research challenged earlier assumptions about when relative plate motions began, pushing back the oldest direct evidence by about 140 million years. Before the first continents formed, there were no large stable landmasses on Earth. It really brings to life the history of just how dynamic the Earth has been through all of its time.
Research shows that differential motion between lithospheric blocks was occurring by ~3.48 billion years ago, far earlier than scientists previously believed for such direct evidence, altering our conception of Earth's early evolution.
Earth is the only planet in the solar system known to have active tectonic plates. Other planets and moons show tectonic activity, but none display true plate tectonic behaviour such as seafloor spreading, subduction, or long-term crustal recycling.
This activity causes geological changes on the surface, recycles rock, and leads to the formation of mountains and oceans. Previously, scientists believed that clear evidence of relative plate motions began around 2.7 billion years ago. These new findings show that Earth has been tectonically active far earlier than expected.
Researchers working in the Pilbara Craton in Western Australia collected rock samples from this region. The rocks contained minerals that recorded some of the physical and chemical properties of the early crust when they formed billions of years ago.
The orientation of the magnetic minerals demonstrated significant horizontal and latitudinal movement of portions of Earth's crust (with the East Pilbara Craton moving rapidly poleward while the Barberton region in South Africa stayed near the equator), proving that tectonic activity was already underway earlier than previously believed.
This discovery creates additional explanation of the Earth being capable of sustaining life as a result of stable conditions established due to the Earth's evolution due to early mobile lithosphere activity creating the geologic and biologically productive environments that will have given rise to life.
It also provides scientists with a means to understand how different types of planetary bodies such as Mars and Venus have evolved. Earth's evolutionary history continues to surprise us. Knowing that relative motions between lithospheric blocks were already occurring at ~3.5 billion years ago indicates how unique and dynamic our planet has been and continues to be.
Reference: Brenner, A. R., et al., (2026). Paleomagnetic detection of relative plate motions and an infrequently reversing core dynamo at 3.5 Ga. Science. https://doi.org/10.1126/science.adw9250