ROCKS

Talk Outline

• What are Rocks? What are Minerals?

• Types of Rocks

– Igneous Rocks

• Extrusive

• Intrusive

• Igneous Rocks Identification

– Sedimentary Rocks

– Metamorphic Rocks

• The Rock Cycle

• Conclusion

What are Rocks? What are Minerals?

What are Rocks? What are Minerals?

• made up one or more minerals pure (made of same substance)

• no definite shape have some shape

• some have fossils no fossils

• color is not same

Types of Rocks

Igneous Sedimentary Metamorphic

Igneous Rocks

• Fire Rocks

• Magma (or molten rocks)

• Cooling and solidification

Igneous Rocks

Extrusive Igneous Rocks

• Volcanic

• Fine-grained

• Cooling and solidifying quickly

• Basalt, Rhyolite (sialic), Andesite,

Extrusive Igneous Rocks

Intrusive Igneous Rocks

• Plutonic

• Coarse-Grained

• Cool slowly

• Granite, Diorite, Gabbro

Intrusive Igneous Rocks

Igneous Rocks Identification

• Granite (& Rhyolite)▫ High in Si + O

▫ Low in Fe + Mg

▫ Mostly feldspar & quartz

▫ Light-colored

• Basalt (& Gabbro)▫ Low in Si + O

▫ High in Fe + Mg

▫ no quartz, abundant ferromagnesian minerals

▫ Dark colored

• Andesite (& Diorite- intermediate)

The Rock Cycle

Sedimentary Rocks

• Sediments are compacted and cemented together

• Caused by weathering, erosion and deposition

• Often contain fossils

• Sandstone, limestone, chalk and coal

Sedimentary Rocks

• Wind and water break down the earth

• Bits of earth settle in lakes and rivers

• Layers are formed and build up

• Pressure and time turn the layers to rock

How They are Made ?

Sedimentary Rocks

Sandstone

Limestone

Sedimentary Rocks

Sedimentary Rocks

Chalk

Metamorphic Rocks

• «Morphed» or changed

• Once igneous or sedimentary

• Formed by high pressure and heat

Metamorphic Rocks

Granite Gneiss

Igneous Metamorphic

It’s morphin time

Metamorphic Rocks

Shale Slate

Igneous Metamorphic

It’s morphin time

In Conclusion,

• Made from minerals

• 3 different groups

• Rock cycle