Bell Work: 9/23/09

1
Bell Work 10/13/11

• Work on Rock Cycle Paper Plate.
• If you are finished with paper plate, do the
  section Review questions pg. 367.

compaction cementation
deposition
deposition
solidification
2
Objectives

• Identify the major processes that drive the rock
  cycle.
• How are igneous rocks formed?
• How would the texture of igneous rocks change if
  the rock cooled quickly vs. slowly?
• What is the difference between intrusive igneous
  rocks and extrusive igneous rocks?
• Label a diagram that depicts the three different
  rock types.

3
Igneous Rocks From Fire!

• Igneous rocks get their name from the Latin word
  for fire igneus. The name is appropriate
  because these rocks are born of fire.

4
Igneous Rock

• Discuss with your group
• Where do igneous rocks come from?
• ___________ _________ forms when hot, liquid
  rock, or __________, cools and solidifies.
• The type of igneous rock that forms depends on
  the composition of the magma and the amount of
  time it takes the magma to cool.

Igneous
rock
magma
5
Igneous Rock

• The longer it takes for magma or lava to cool,
  the more time mineral crystals have to grow.
• __________ _____________ ____________
• Examples of coarse-grained igneous rocks
• Granite
• Gabbro

larger crystals
coarse texture
more time
6
Igneous Rock

• The less time magma takes to cool, the less time
  crystals have to grow.
• __________ _____________ ____________
• Examples of fine-grained igneous rocks
• Obsidian
• Basalt

less time
smaller crystals
fine-grained
7
Group Activity

• Rank the rock samples by how fast they cooled.
• Pay careful attention to the grain size of each
  rock.
• Write the names of the rocks in order from
  fastest cooling to slowest cooling.

8
Igneous Rock Formations

• Rock formed from the cooling and solidification
  of magma beneath the Earths surface is called
  ____________ ___________ _________.
• Rock that forms from magma that erupts, or
  extrudes, onto the Earths surface is called
  ____________ ___________ _________.

Intrusive
Igneous
rock
Extrusive
Igneous
rock