Why Earth has a supercontinent cycle

Question

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?

In: 1126

Answer 1

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.