How do we know how earth looked like millions years ago? Like places of continents and how they moved?
In: 5
The continents are kind of like a puzzle, some literally in shape (ex. Africa and S. America), but all of them in rock formations. Whole geological formations just match others on other continents in ways that only makes sense if they were the same one.
Only it’s not just one “rock puzzle”, it many layers of them, like assembling one puzzle, printing a new picture over it and re-cutting it a different way. It’s not even a metaphor, that’s literally what happened. New rock layers were laid down on top of old ones, all the while continents merge and separate in new configurations.
But it took centuries to figure it all out. Matching up all the rocks of different ages to other rocks of the same age in different places was the life’s work of generations of geologists.
To put it simply, the continents sit on massive mostly round plates on the surface of the earth. These tectonic plates move very slowly over time, and we can sort of figure the path and trace it back to where the plates, and the continents, likely were in the past.
Basically a combination of geology and paleontology (studying dinosaurs). When looking at core samples of the earth, they can see the same things on continents that are now across oceans. There are also species of dinosaurs found on multiple continents and we know they didn’t swim there. So they had to have some way to travel between those fossils. If you look at the continents, you can kind of see that they could fit together. To map it out, they basically look at the core samples and connect the dots between ones that are similar.
We know the direction and speed they are moving now, so we can just run that in reverse to get a good idea of what they looked like in the past.
We can also use fossils and different minerals, where you might find groups of species and mineral that appear in locations on totally separate continents [it’s likely those locations used to actually be next to each other](https://letstalkscience.ca/sites/default/files/styles/x_large/public/2022-11/Fossil_map.png?itok=TIWoaj02)
Latest Answers