Millions of years ago, the Earth didn’t look quite like it does today. Yes, of course, you know that once upon a time dinosaurs roamed the planet. But the geology lesson for today isn’t about dinosaurs. We’re talking about a time when all the continents were one jumbled landmass. If you’re still scratching your head, we’re talking about Pangaea. Consider this a crash course on the planet’s most well-known supercontinent.
What was Pangaea?
Pangaea was a continuous landmass that contained all of the continents that we know today: North America, South America, Africa, Australia, Asia, Antarctica, and Europe. Pangaea (also spelled Pangea) existed from the Late Paleozoic Era through the Late Triassic Era, or 280 to 230 million years ago. During this time, Pangaea covered roughly a third of the Earth’s surface and was surrounded by one massive ocean that is called Panthalassa.
How did Pangaea form?
We know that Pangaea was formed through geological activity. In particular, movement along the Earth’s tectonic plates for millions of years led to all of the continents eventually shifting together into a supercontinent. And this is why even if you look at a modern map of the Earth, you can see how the continents would have fit together like puzzle pieces.
Before Pangaea, various landmasses existed that ranged from microcontinents to supercontinents. These masses were constantly colliding with each other and resulted in supercontinents such as Euramerica and Gondwana. Euramerica was composed of North America, multiple microcontinents, and Eurasia (Europe and Asia), while Gondwana contained Africa, Australia, South America, Antarctica, and the Indian subcontinent. These were the two final supercontinents that eventually collided to form Pangaea.
What was Pangaea like?
Thanks to fossil records, we can determine the climate that existed during Pangaea’s existence. Since it was a supercontinent that featured mountain ranges, experts believe that Pangaea’s interior was extremely arid with minimal rainfall because of the mountains that would have blocked virtually all moisture. However, the supercontinent was also home to a tropical paradise. Proof of this is in the coal deposits that we find today in areas that were once along Pangaea’s equator. The supercontinent was also home to dynamic and diverse flora and fauna. And it’s these fossil records that help provide proof that Pangaea existed.
When did Pangaea break apart?
Pangaea’s formation was gradual, and its end was also a slow process. Thanks to those tectonic plates, around 200 million years ago, the supercontinent began to break apart. But the landmass didn’t automatically break into seven continents. First, Gondwana broke off from Pangaea. What was left of Pangaea became known as Laurasia and was composed of North America and Eurasia.
Gondwana further splintered off roughly 150 million years ago with the Indian subcontinent being the first to separate from the supercontinent. And then 60 million years ago, Laurasia broke apart, with North America and Eurasia fully separating. As the separating land created new continents, new oceans formed. Geologists believe that the Atlantic Ocean was the first to form as Gondwana shifted away from Pangaea. In particular, it first formed between northwestern Africa and North America.
How was Pangaea discovered?
We owe the discovery of Pangaea to the scientist Alfred Wegener in 1927. Besides just observing from a map that the continents look like they could fit together, other clues hinted at a supercontinent. In particular, coal samples from far-flung locations like Pennsylvania, Poland, and even Germany had the same composition.
Likewise, plant and animal fossils from previous geological eras can be found on multiple continents. But similar fossils and land compositions could be possible only if these landmasses were connected at some point. While Pangaea isn’t the only supercontinent in Earth’s history, its discovery was a breakthrough in understanding geology and, specifically, the importance of tectonic plates and rift zones.