The Three Different Types of Rocks: • Igneous • Metamorphic • Sedimentary
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 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
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.) • 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 • Some examples of igneous rocks are obsidian, pumice, scoria, and granite.
Metamorphic 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.) • 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 Rocks • Some other examples of metamorphic rocks are schist and gneiss.
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 Rocks • Some types of sedimentary rocks are gypsum, conglomerate, shale, sandstone, and limestone.
Summary • 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 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