Go back further still and all the continents had coalesced to form Nuna - the oldest known supercontinent. Wind the clock back further and Rodina was the ruling supercontinent between 750 million and 1.3 billion years ago. Today, geologists know Pangea was just the most recent in a series of mighty supercontinents. If these ancient crystals really are from an old continent lost in Pangea’s breakup, it’s likely that other ancient crystals can be found at similar sites. “We're going to have a lot of fun testing the idea,” says Mitchell, who admits he's already thinking about buying a plane ticket to Iceland - the only place in the world where a mid-ocean ridge bubbles up to the surface. Geologists are thrilled at the find as it better helps them map Pangea. Scientists now know the c-shaped supercontinent consisted of two smaller continents that collided at the equator: Laurasia in the Northern Hemisphere, which encompassed North America, Greenland, Europe and much of Asia, and Gondwanaland in the Southern Hemisphere, which was composed of South America, Africa, India, Australia and Antarctica. During this period continental drift, driven by the massive forces of plate tectonics, had just begun to break the supercontinent of Pangea into Laurasia in the north and Gondwana in the south. This is how the western hemisphere of the Earth may have appeared 200 million years ago during the Early Jurassic period.
Look at an atlas and it might be tempting to slide the Americas eastward, hooking them into Africa like three puzzle pieces. Such oddities made sense only if the continents were once nuzzled up next to each other as parts of Pangea. Or the Appalachian Mountains of the eastern United States and Scotland’s Caledonian Mountains, which were so similar they seemed geologically related. Or the extinct seed fern Glossopteris, which once thrived in the polar circle and the tropics. Consider fossils of the lizard-like animal Lystrosaurus, which have been found in South Africa, India, and Antarctica. The world’s latest enormous landmass was first hypothesized when scientists noticed eerie similarities across vast stretches of the globe.
That rhythm will continue to bring the next supercontinent into view hundreds of millions of years from now in a world that will look almost alien to our own.
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