The Three Different The Three Different Types of Rocks:Types of Rocks:

•Igneous

•Metamorphic

•Sedimentary

Where Do Rocks Come From?Where Do Rocks Come From?

• Where do you see rocks?

• Mountains

• Canyons

• Riverbeds

• All rocks are all made of minerals.

• As a matter of fact, rocks are made up of 2 or more minerals.

The Rock CycleThe Rock Cycle

• The rock cycle is an ongoing process that never stops

• There are three different types of rocks: Igneous, Metamorphic, and Sedimentary

• With melting, heat/pressure, and weathering/erosion rocks change into different types of rocks

• Rocks are always changing

The Rock Cycle (Cont.)The Rock Cycle (Cont.)

Igneous Rocks Igneous Rocks

• The word Igneous comes from the Latin word Ignis, which means Fire.

• Igneous Rocks come from the magma inside of a volcano

• There are two types of igneous rocks:

• Extrusive • Intrusive

Igneous Rocks (Cont.)Igneous Rocks (Cont.)

• Extrusive igneous rocks are formed when a volcano erupts

• The magma will spill all over the surface and cool, this is an extrusive igneous rock

• An intrusive igneous rock is formed when magma doesn’t reach the surface

• Instead, it forces its way into cracks and spaces between other rocks already inside the Earth and turns solid before ever reaching the surface

• Magma that never makes it to the surface turns solid slowly,  because it takes it a long time to cool inside the hot Earth

Types of Igneous Rocks Types of Igneous Rocks

• Some examples of igneous rocks are obsidian, pumice, scoria, and granite.

Metamorphic RocksMetamorphic Rocks

• Metamorphism means “to change”

• Normally when we think of metamorphism, we think of caterpillars changing into butterflies

• Through heat and pressure an igneous rock turns into a metamorphic rock

Metamorphic Rocks (Cont.)Metamorphic Rocks (Cont.)

• Marble is a type of metamorphic rock

• It is formed limestone, which is an igneous rock

• The Taj Mahal in India was built of all marble

Types of Metamorphic RocksTypes of Metamorphic Rocks

• Some other examples of metamorphic rocks are schist and gneiss.

Sedimentary Rocks Sedimentary Rocks

• Sedimentary rocks can be formed from many different ways

• Sedimentary rocks are worn down by wind and rain and are washed downstream where they settle at the bottom of rivers, lakes and oceans.

• Eventually, with the pressure of everything above the sediments a sedimentary rock is formed!

• Some of the ways that sedimentary rocks come from are:– Layers of other rocks– Dead animals/plants– Sand

Types of Sedimentary RocksTypes of Sedimentary Rocks

• Some types of sedimentary rocks are gypsum, conglomerate, shale, sandstone,

and limestone.

SummarySummary

• The three different rocks are: igneous, sedimentary, and metamorphic

• There are two types of igneous rocks: intrusive and extrusive

• Igneous rocks come from the magma inside of volcanoes

• Metamorphic rocks “change” with heat and pressure • Sedimentary rocks are formed from layers of other rocks

(at the bottom of lakes/rivers/oceans), dead animals/plants, or sand.

Works CitedWorks Cited

• http://www.promotega.org/ksu00006/types.htm

• http://earthnet-geonet.ca/images/glossary/magma.jpg

• http://geology.csupomona.edu/alert/metamorphic/metarxs.htm

• http://csmres.jmu.edu/geollab/fichter/SedRx/SimpModl.html