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What are facts against Pangaea?
Answer 1:

Thanks for your question! To date, there is no evidence against the existence of the supercontinent Pangaea. In fact there is instead a lot of evidence supporting the theory that Pangaea assembled approximately 300 million years ago and began to break up again around 175 million years ago. The theory of plate tectonics explains how the continents have moved in the past and continue to move today, and evidence of plate tectonics helps scientists understand when and how Pangaea formed.

Here is the evidence in support of Pangaea

There are fossils from the same species on continents that are now very far apart. Some examples are fossils of Lystrosaurus which was a four-legged herbivore approximately the size of a pig, that are found in South Africa, India, and Antarctica. Also found in South Africa, India, and Antarctica are fossils of the plant Glossopteris. In Brazil and West Africa paleontologists have found fossils of the freshwater reptile Mesosaurus. It wouldn’t be possible for these fossils to be on these continents that are now very far apart if they had not once been connected or at least much closer together. Today, many of the same species of plants and animals live on continents that are far from each other, but this is because humans have brought plants and animals with them when they traveled overseas. 300 million years ago, the only way for a plant or animal species to get to another part of the world would be for it to walk, swim, or get carried by the wind.

Geologists have found rock formations and trends in the east coast of South America that match with rocks in West Africa, like a giant jigsaw puzzle. The reason these rocks match is because they formed when the continents were connected to one another.

When glaciers move across Earth’s surface they leave easily identified deposits and marks and grooves in rocks. When geologists look at glacial deposits, they can see which direction the ice was flowing and reconstruct the location of the glaciers. An ice age occurred from about 326 – 267 million years ago, and the glacial deposits from this time formed in southern South America, southern Africa, southern India, Antarctica, and Australia. These places are now far apart, but when Pangaea existed the glacial areas were connected and located near the South Pole.

Finally, the strongest evidence for the existence of Pangaea is something called paleomagnetism. Some rocks have minerals inside ofthem that are magnetic, and when the rock forms those magnetic minerals will line up and point to the North Pole. When you use a compass for directions (not a gps or an iPhone but an actual compass with a needle), the needle points to the North Pole because it is magnetic and the needle is lining up with the Earth’s magnetic field. For the same reason your compass needle points north, the magnetic minerals in rocks point north when the rock forms like tiny geological compasses. This is called paleomagnetism. Geologists can measure the direction that the magnetic minerals within rocks are pointing, and the age of the rock, and put this together to figure out where the rock was in relation to the North Pole when it formed. If we do this for many rocks on many different continents we can get a picture of how the continents have moved through time, and we can see that between about 300 and 175 million years ago the continents were together in a supercontinent called Pangaea.

So we have a lot of evidence that Pangaea existed, and have not found any evidence that disproves the existence of Pangaea, although there is still a lot we don’t know yet and geologists are still working on figuring out all the details. When the theory of continental drift, which is the theory that the continents have moved positions throughout Earth’s history, was first proposed it received a lot of criticism because there wasn’t a good understanding of how the continents moved across the surface of the Earth. Today, we understand that the continents have moved because of plate tectonics.

The surface of the earth is made up of many rigid “plates” that move around in relation to one another. These plates move because they are riding on top of part of the earth called the asthenosphere. The asthenosphere flows very slowly through time and drags the overriding tectonic plates with it. Some of these plates collide with each other, some move away from one another, and others slide past each other. When plates move towards each other one plate gets subducted below the other plate and moves into the layer of the earth we call the mantle, where it eventually melts and gets recycled back into the earth. In places called mid-ocean ridges,plates are moving apart from each other and magma rises between the two plates and cools into new seafloor.

When plates move past each other a large fault forms on the earth’s surface which often creates very large earthquakes. An example of one of these types of plate boundaries is the San Andreas Fault in California. The San Andreas Fault is the boundary between the Pacific plate and the North American plate. The continents are part of the tectonic plates, so when the plates move around the continents move with them. This means that as plates have moved through time, so have the continents.

Although we understand a lot about how and why tectonic plates move, there are still a lot of things we don’t yet understand. Geologists are still working to figure out exactly when and how the continents came together to form Pangaea, and also what causes continents to start rifting apart when supercontinents break up. Despite the questions we still have about plate tectonics, there is overwhelming evidence that Pangaea did exist and it is widely accepted by scientists.

I hope this answers your question!!

Answer 2:

Pangaea formed about 350-300 million years ago from the collisions of the continents of Laurentia, Avalonia, Baltica, Gondwana, Siberia, and Sinia. It broke up 250-200 million years ago into the pieces of Laurasia (which further became North America and Eurasia) and Gondwanaland (which became South America, Africa, Madagascar, India, Antarctica, Australia, and New Zealand).



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