Why are mountains so big and so tall?
Mountains have been building for millions of years, and they form in different ways.
Land is made up of huge masses of the Earth’s crust, called “tectonic plates,” which move around as a result of geologic activity below the surface. As these plates move around and smash up against each other, their edges crumple and are pushed upwards, forming mountains. And these plates keep on pushing against each other, which means our current mountain ranges are still growing, although verrrrrry slooooooowly.
Mountains can also be formed by volcanic activity below the surface of the Earth. As hot molten rock, called magma, is pushed up to the surface and erupts out, it eventually cools and becomes solid rock. The islands of Hawaii have very active volcanoes, so they are always changing with every eruption!
See for yourself: Move mountains!
Try out some small-scall plate tectonics!
Grab 2 medium-sized pieces of aluminum foil and crumple them up a little bit so that they have some texture.
Lay them down relatively flat on a table (but don’t smooth them all the way out!) and push the pieces together, forcing the edges to connect.
The more you push them, the more the parts that are touching move up, forming little “mountains!”