Dr. Schmidt explains the world: Where are the continents going?

The seven continents on Earth could become one large supercontinent in a few 100 million years. How does this happen?

They move, and you can measure that pretty accurately with GPS. The continental edges currently move between one and ten centimeters per year. That’s not a lot considering how big they are. But we’re talking about millions of years, and millions of centimeters is a completely different order of magnitude.

There was already a supercontinent.

At least 300 million years ago there was a continent in which virtually all of the land masses we know today were connected. The idea that this must have been the case is quite old. When the first reasonably accurate world maps were created in the 16th century, one of the cartographers concluded, based on the coastlines of South America and West Africa, that there must have been something connected. Because if you take the continents as puzzle pieces and put them together, you see a pretty good fit. And that exists elsewhere too: Madagascar, for example, was originally attached to what is now Africa. And when paleontology emerged, i.e. since extinct plants and animals were excavated and dated from ancient rock layers, it was also seen that the same animal and plant species occurred on what are now separate continents. The theory of evolution would lead us to expect greater differences in separate habitats. Dinosaur skeletons have now even been found in Antarctica, which would definitely be unsuitable for cold-blooded animals. This means that Antarctica, as a continent, must have once been much closer to the equator.

How and why do the continental plates move?

Alexander von Humboldt believed that there must have been a catastrophic water breakthrough between Africa and South America. A little earlier, Benjamin Franklin had suspected that the earth’s surface would float as a crust on a very dense, viscous liquid. This would make it conceivable that continents could move. This is relatively close to the theory of the Austrian Otto Ampferer, who postulated that the liquid mantle beneath the earth’s crust ebbs up, so to speak, and that these ebbs provide the kinetic energy for the continental plates. This theory has dominated since the 1960s as an explanation for the continental drift discovered by Alfred Wegener.

Can you predict where the plates will move?

This is a weak point. Some time ago there was an investigation into why Africa and South America were not separated in a different place. Because there is also an old fault zone from Libya to Nigeria. And the newer East African Rift Valley from the Red Sea to Lake Malawi. Current models say that the earth is moving further apart there, so that at some point the sea will break through Africa. But that will take a few million years. The question is anyway whether there will still be people who could be threatened by it.

Could people live well on a supercontinent?

In any case, its emergence would involve significant changes that would be catastrophic by human standards. For example, one has to expect large-scale volcanism, which will cause massive increases in CO₂-concentration of the earth’s atmosphere would result in a concentration far above what we have done so far as a human civilization. The average temperature on this emerging supercontinental plate will then be around 40 degrees. This is probably only for lizards and insects.

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