The Rock cycle
The three main types of rock are igneous, sedimentary and metamorphic which are each formed in different ways. the rock cycle is a process that reuses, recycles and rocks. Each rock can be changed into each different type of rock. Most rocks began as igneous rocks because igneous rocks are formed fro magma, when it cool and solidifies into rock. When igneous rocks are exposed on the surface of the earth, time and weathering break down the rocks into smaller pieces. This is called weathering and erosion. Wind and water carry the smaller pieces of rock into sediment beds. Sedimentary rocks form when the sediment beds become buried and the small pieces of rock get cemented together. If the sedimentary rock is exposed to the surface, it eventually gets eroded and forms new sedimentary rocks. However if the sedimentary rock gets buried deep into the ground, then heat and pressure will eventually bake the rock. The rock will become a new type of rock. This process is called metamorphosis. The new rock that has formed is called a metamorphic rock. Metamorphosis can also happen to igneous rocks. Metamorphic rocks can also be weathered and eroded therefore eventually changing into sedimentary rocks, but if the are forced deeper into the ground, the metamorphic rocks can melt and form magma. igneous rocks are then formed if the magma cools on the surface of the earth.