Supercontinent

Earth science · geology · plate tectonics · ancient Earth

Continents collide. Earth's continents are always moving on giant puzzle pieces called tectonic plates. When most of them crash together over millions of years, they form a supercontinent, a massive landmass made up of nearly all the world's continental blocks stuck together.

Ancient giant lands. The most famous supercontinent was called Pangaea, which existed about 300 million years ago. It contained almost all the continents we know today, but then slowly broke apart into the separate continents we see on maps now.

75% rule matters. Scientists say a grouping of continents only counts as a supercontinent if it includes about 75% or more of all the continental crust that exists at that time. This helps geologists decide whether ancient landmasses were really supercontinents or just regular groupings of continents.

They come and go. Supercontinents don't last forever. Over tens of millions of years, the plates keep moving and pushing, eventually breaking the supercontinent apart into separate continents that drift to new locations.

Hard to spot early on. Scientists struggle to identify supercontinents from Earth's earliest times because the rocks are very old and there's less clear evidence. Different geologists sometimes disagree about which ancient landmasses truly qualified as supercontinents.