See a Billion-Year Dance of Earth’s Tectonic Plates in 40 Seconds
By Jason Dorrier -February 14, 2021
To stitch together plate simulations, geophysicists search for and record geologic formations correlating to past tectonic movement along plate borders. They also observe magnetic minerals in rock layers to determine the strength and direction of the Earth’s magnetic field over time. Together, this information offers clues about where rocks from around the world were located in the distant past.
The new research isn’t the first such simulation, nor is it the first to go so far back in time. In their paper, the researchers include a family tree of nine other full-plate reconstructions.
Until now, however, all the models have focused on shorter periods of time. Over the last four years, the team quilted four of these models into the simulation you see above—the first continuous, full-plate reconstruction spanning the last billion years.
And the model is, of course, more than a mind-boggling video.
Plate tectonics inform our understanding of the Earth’s composition, climate, and how life emerged and evolved. “Our planet is unique in the way that it hosts life,” said Professor Dietmar Muller, coauthor and leader of the University of Sydney’s EarthByte geosciences group. “But this is only possible because geological processes, like plate tectonics, provide a planetary life-support system.”
Tectonic motion is an evolutionary force—as populations of animals merge and separate over eons—and tectonics also drive planetary carbon and mineral cycles and affect sea level. All this influences both climate and creatures over geological cycles.
This week, in a separate study, for example, scientists from China’s Peking University said a thinning of Earth’s crust from roughly 1.8 billion to 0.8 billion years ago suggests a slowing of plate tectonics. As a result, the formation of mountains ground to a halt and literally wore down to nothing.
Their findings coincide with a period of slow evolution, known as the “boring billion.” More research is needed, but they suggest slower tectonics and mountain formation may have meant less replenishment of the life-sustaining elements upon which animals depend, and thus, lower productivity stalled evolution.
Science aside, it’s fascinating to travel so far into the past, when just three oceans—the Mirovoi Ocean, Mozambique Ocean, and Mawson Sea—lapped at the shores of supercontinent Rodinia. Or when Antarctica, now buried under miles of ice, was a rather balmy place, having wandered up near the equator.
Wait long enough, and the face of the planet will shift again, rearranged by its tectonic dance through deep time.
Image Credit: NASA