It’s been estimated that in all of Earth’s history, there have been 7 supercontinents, with the most recent one being Pangaea.
The next supercontinent (Pangaea Ultima) is expected to form in around 250 million years.
Why is this the case? What phenomenon causes these giant landmasses to coalesce, break apart, then coalesce again?
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Are you familiar with a [clacker toy?](https://j.gifs.com/0A6.gif)
Imagine that, doing the up/down style of clacking shown above (rather than the round and round style of its use), but with something like 15 clacker balls of differing size, on slightly different arcs, but all with the same radius. They reach the top, and that’s Pangea. Then, they bounce off each other (at geological speeds, so measured in the hundreds of millions of years), and swing back down to the bottom (Pangea Ultima, or Pangea VIII), at which point they bounce off each other *again,* back towards the top (Pangea IX).
Over time, the speed of their travel will get slower and slower (as their kinetic energy is turned into mountains with each collision), until they *stay* in a super continent.
…but in the mean time, they keep bouncing against each other, back and forth.
You guys are so behind the times he’s gonna use it as a tax rate off for the rest of his life.
Why *does* Earth *have* a supercontinent cycle*?*
I do not like this shift to dropping verbs and punctuation.
When the continents are apart, they move. When they move, they have a high likelihood of eventually hitting another one. When the continents are together, there isn’t exactly anywhere to move other than apart again.
Due to probability of movement and the fact that continents that have already slammed into each other are much more likely to separate than go further into each other, it makes it most likely that a cycle would emerge.
The top comments here are all correct, and even more broadly speaking this has something to do with the formation of the moon – as far as we know a large mercury sized object slammed into early Earth, threw off a bunch of material that eventually coalesced into the moon, and basically blew a hole in the early continents and “cracked” the crust, plate tectonics are essentially the million year long ripples of this event. That’s an unbelievably simple picture of it, but this is ELI5.
I dont know but I cant wait till i can drive my diesel pick up truck to Europe on my vacation!
Have a read of some of Graeme Begg’s work.
Possible that they are almost self organised, and the breakup of the previous supercontinent is the driver for the breakup of the new supercontinent. Basically just shifting backwards and forwards across the surface.
Keeping it really simple, the surface of the earth moves by sinking on one edge and splitting apart at another. The driver for this is in a basic (for supercontinents) is suggested to be very hot upwelling of mantle forcing the surface apart. Once the process is rolling, the sinking edge continues the process by dragging the rest of the plate with it.
The sinking edge eventually breaks and sinks into the mantle, stopping the process. The broken edge keeps sinking, becoming super hot and possibly reaches core/mantle boundary.
The superheated broken edge shoots back up to the surface as an “alpha plume”, and the whole process starts again. This is thought to be on a roughly 800Ma cycle, aligning with supercontinent cycles.
This is grossly oversimplified, but if interested search G.Begg and Griffin for supercontinent cycles on Google scholar.
This process is important for mineral exploration, as the VAST majority of magmatic Nickel deposits form on the 800Ma cycle, and are strongly correlated with break apart phases of supercontinents
It’s as random as anything else in nature. The scientists were able to establish some patterns of cause & effect, however these patterns are only based on what we can observe directly, which isn’t much from the point of the whole planetary movement, while leaving the fluid/thermal dynamics of the mantle movement still a random process.
Well, the first ever supercontinent was considered one by default because it was the only continent
Dr Farnsworth: “All future Mammals dead, you say?” [said in the voice of Professor Farnsworth]
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