Classification of Rocks Each rock type is classified by how they are formed The 3 Rock Types Igneous Sedimentary Metamorphic What makes them different? What do they have in common?

(over geologic time) into another type of rock Igneous Rocks Formed from the cooling and crystallization of lava or magma (molten rock) Intrusive or Extrusive Mafic or Felsic Metamorphic Rocks Formed by heat and pressure changing other rocks Foliated or non-foliated Sedimentary Rocks Formed by the compaction and cementation of sediments into layers of rock Clastic (rock fragments) OR Nonclastic: Chemical Organic All rocks Can be composed of minerals, volcanic glass, organic matter, or other materials Can be changed (over geologic time) into another type of rock Recycled

The Rock Cycle All rocks are in a constant (although extremely slow) state of change due to: Weathering and erosion (breaks rocks into sediments) Compaction and cementation (creates new Sedimentary rocks) Movement of Earth’s crust (causes pressure and heat) Volcanic activity (melts rocks into magma and creates igneous rocks) The Rock Cycle shows how one rock type can transform into another type of rock.

Rock Cycle

Rock Cycle

Sedimentary

Igneous

Igneous

Metamorphic

Geothermal

Rock Type Venn Diagram Igneous Rock Sedimentary Rock All Rock Types Metamorphic Rock