The Rock Cycle

The Rock Cycle

1. Igneous

   • Formed from Magma which is pushed up to the surface of the crust - Often out of volcanoes
   • There are two types of Igneous rocks
     • Intrusive: Cool slowly underground and eventually gets exposed to the atmosphere. They form Large Crystals
     • Extrusive: Cools quickly above the ground they usually form Smaller Crystals.

2. Sedimentary

   • These are formed from layers of sediment (Rock fragments or dead matter) laid down in lakes or seas over millions of years. These rocks could also be formed when water evaporates (The change of state from a liquid to a gas) and leaves a dissolved solid (Like salt) behind
   • The layers are cemented together by other minerals.
   • Fossils can form in sediments. These are the long dead remains of plants and animals.

3. Metamorphic

   • These are the result of heat and increased pressure acting on existing rocks over a long period of time
   • They might have tiny crystals and some have layers.