Earth ScienceCoach Williams

Room 310B

Igneous Rocks

Chapter 5

What are Igneous Rocks

5.1

Crystallized magma “Ignis” = fire Lava- magma flowing onto surface

Igneous Rocks

Extrusive◦ Cool quickly, fine-grained, on surface

Intrusive◦ Cool slowly, coarse-grained, beneath surface

Types of Igneous Rocks

Identify: Igneous Rocks

Slushy mix of molten rock, gases, minerals SiO2 most abundant 800 – 1200°F to melt rocks Factors that affect magma

◦ Temperature- deeper = hotter◦ Pressure- deeper = more pressure◦ Water- affects melting point◦ Minerals- affects melting point

Magma

http://geology.com/rocks/igneous-rocks.shtml

Pictures of Igneous Rocks

Partial Melting◦ Different substances, different melting points◦ Rock parts melt at different temperatures

Fractional Crystallization◦ Magma cools and crystallizes◦ Rock parts crystallize at different temperatures

How Rocks Melt

Relationship: cooling magma/mineral formation

Bowen’s Reaction Series