Principle of cross-cutting relationships

Do you ever play with blocks that are stacked on top of each other? When you take one block off the top, you can see the blocks that are below it. This is kind of like what geologists do when they study rock layers.

They look at the different layers of rock in a certain area and see which ones are on top of the others. If one layer of rock is on top of the others, it must be younger than the ones below it.

But sometimes, things get a little mixed up. Sometimes a rock layer can get shifted or tilted, and end up on top of another layer that it wasn't originally on top of. This is where the principle of cross-cutting relationships comes in.

If you have two layers of rock, and one gets tilted and ends up on top of the other, then you can tell that the tilted layer must be younger than the other layer. This is because you can see that it cuts across the older layer. Think about it like cutting a cake - if you cut a slice out of a cake and put it on top of another slice, the slice on top is younger because it was cut more recently.

So, the principle of cross-cutting relationships helps geologists figure out which layers of rock are older and which are younger based on the way they are arranged.