Igneous rocks Igneous rocks: rocks formed when magma or lava cools and hardens. Igneous is from Latin, meaning “born of fire”. http://www.absorblearning.com/media/attachment.action?quick=12z&att=2795
Lava is found on the surface, magma is found underground.
Igneous rocks Intrusive: forms below the surface when magma cools slowly. It has large crystals (granite). http://www.livra.co.uk/samples2.php?page=granite
Igneous rocks Extrusive: formed when lava cools quickly on the surface of the Earth. Crystals are small (obsidian and basalt)
Igneous-examples and uses Granite: buildings, bridges, and counters Basalt : gravel Obsidian: knives
Famous Igneous Rocks Giants Causeway Stonehenge Easter Island Sugarloaf Mtn.
The black stoneMt. Rushmore Machu Picchu Mt. Fuji
Metamorphic rocks Metamorphic: rock that forms when heat, pressure, or chemicals act on a rock to change its form or composition. Layers are often seen in these rocks. Limestone into marble Granite into Gneiss http://www.classzone.com/boo ks/earth_science/terc/content/vi sualizations/es0607/es0607pag e01.cfm?chapter_no=visualizat ion
Metamorphic rocks Pressure and heat squish the rock into interesting patterns
Metamorphic-example and uses Marble: buildings and sculptures Slate: flooring, roofing, walkways, and chalkboards
Famous Metamorphic Rocks Taj Mahal Trevi Fountain Parthenon
Review What is the difference between a mineral and a rock? –Minerals have specific chemical compositions, rocks are a random assortment of materials –Rocks can have organic materials (shells and plants) mixed in –Rocks may not have a crystal structure VS.
What are the three types of rocks? Igneous Sedimentary Metamorphic
4. Igneous Rock to Metamorphic? Heat and pressure
5. Igneous Rock to Sedimentary Rock? Weather and erode into sediments Sediments compact and cement into sedimentary rock.
6. Metamorphic Rock into Sedimentary Rock? Weather and erode into sediments Sediments compact and cement into sedimentary rock.
7. Sedimentary Rock to Igneous Rock? Sedimentary rock undergoes heat and pressure to become Metamorphic rock, then it melts to become magma, then cools to become Igneous rock. OR Sedimentary rock melts into magma then cools into Igneous rock