The Rock Cycle

Rocks Rock- mixture of minerals, glass, or organic matter compacted together examples: granite, limestone, obsidian

Minerals Mineral- naturally occuring, non-living solid composed of elements or compounds examples: quartz, pyrite, garnet

Rock Cycle The rock cycle shows how rocks are formed and changed from one form to another.

Heat & Pressure = Metamorphic Rock Melting & Cooling = Igneous Rock Weathering & Erosion = Sediment Compaction & Cementation = Sedimentary Rock

Types of Rocks There are 3 types of rocks formed on Earth: –Igneous, Metamorphic, and Sedimentary

Igneous Rocks Igneous rocks are formed when molten rock material (magma) is melted deep inside Earth and cooled as it rises toward the surface of the Earth as lava. 1. Intrusive igneous rocks- rocks that form below Earth’s surface, cools slowly so large crystals are able to form 2. Extrusive igneous rocks- rocks that form near or on Earth’s surface, cools quickly so no large crystals form

Igneous rocks can also be classified by magma type –Basaltic rocks are dense, heavy, dark- colored rocks formed by basaltic magma. Rich in iron and magnesium –Granitic rocks are light colored, less dense, thick, and stiff Rich in silicon and oxygen Creates violent eruptions Discover How Rocks Are Formed