What are the different rock types? Rocks Igneous A mixture of one or more minerals and organic matter Three types of rocks Igneous Sedimentary Metamorphic Form when magma cools Found near volcanoes or at oceanic divergent zone Texture is determined by how fast the magma cools Magma that cools quickly forms smooth grained rocks (smooth to touch) Magma that cools slowly forms course grained rocks (rough to touch)

Igneous Rock Formations Intrusive Igneous rocks form below the earth’s surface or inside the Earth Have course grained texture Extrusive Igneous rocks form on the Earth’s surface Have a smooth texture because the magma cools quickly

Sedimentary Rocks Formed from sediments made during the erosion of other rocks Sediments settle in low places, usually near or under bodies of water Over time the sediments form layers that are compacted together and form rocks Sedimentary rocks are almost always found in strata or layers

Contact metamorphism occurs when rocks are heated by nearby magma Metamorphic Rocks Form deep in the Earth where heat and pressure change rocks into new and different types of rocks The atoms in the minerals are actually rearranged and turned into new minerals which make new rocks Contact metamorphism occurs when rocks are heated by nearby magma The heat causes the minerals in the rocks to change Regional metamorphism occurs deep in the earth where pressures build up and are able to create a chemical change in the rocks