Rocks Rock!!!

Rocks

• Rock: A mixture of minerals, rock fragments, volcanic glass, organic matter or other natural materials.

Rock Uses• Rocks have been used throughout history

for buildings, weapons, tools, and in art.

Types of Rocks

• There are three main categories of rocks– Igneous– Sedimentary– Metamorphic

Igneous Rocks(ig-nee-us)

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 RocksGiants Causeway Stonehenge

Easter Island

Sugarloaf

Mtn.

The black stone Mt. Rushmore

Machu Picchu Mt. Fuji

Sedimentary Rocks(said-ah-men-tarry)

Sedimentary rocks• Sediments: loose materials, such as rock

fragments, mineral grains, and the remains of once living organisms

• Sediments are moved by wind, water, ice, or gravity.

Sedimentary rocks• Sedimentary: rock formed when sediments

are compacted and cemented together. Rock may feel grainy or sandy and weak.

Sedimentary rocks

• Many fossils are found in sedimentary rocks.

Sedimentary-examples and uses

• Sandstone: building materials

• Limestone: used to make cement

Famous Sedimentary Rocks

SphinxHaolong Bay

Angkor Wat

Chichen Itza

Uluru (Ayers Rock)

Monument Valley

Metamorphic Rocks(met-ah-more-fic)

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/books/earth_science/terc/content/visualizations/es0607/es0607page01.cfm?chapter_no=visualization

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

Rock Cycle

Rock Cycle

• Rock cycle: a model that describes how rocks slowly change from one rock type to another rock type over time.

Rock Cycle

Rock Cycle• Changes to rocks

occur due to melting, cooling, weathering and erosion, compaction and cementation, and heat and pressure.

Rock Cycle Quiz

• How does one rock change into another? Use your rock cycle chart to figure it out!

1. Igneous to sediments?

• Weathering and erosion

2. Sedimentary rock to Metamorphic?

• Heat and pressure

3. Igneous Rock to Magma?

• Melting

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

The End of Rocking Rocks!

Famous Rocks around the World

• http://academic.brooklyn.cuny.edu/geology/grocha/monument/rocks.html