Over time, the layers are compressed and glued together.Metamorphic rocks are formed from other rocks, igneous or sedimentary, which are heated and compressed underground.Igneous rocks are formed ...

Sedimentary rocks are formed by small rock pieces which are transported by rivers and laid down in layers. Chalk is a sedimentary rock. Metamorphic rocks are formed when another rock is under heat ...

The next layer is the mantle. Many people think of this as lava, but it's actually rock. The rock is so hot, however, that it flows under pressure, like road tar. This creates very slow-moving ...

The beginnings of a strange layer of molten rock deep inside the Earth may have finally been figured out by geoscientists.

The Chipmunk Shark was believed to have swam along the ocean floor that is said to have covered much of central Kentucky during the Middle Mississippian period, officials claim.