1. Earth Unit
Lesson 5 – Igneous Rock

2. Students will identify the characteristics of igneous rock.
Objectives
Students will identify the characteristics of igneous rock.
Students will understand how rocks are formed.

3. Vocabulary
Igneous rock: rocks formed when magma from inside the earth cools and hardens on the earth’s surface.
lava: magma that has reached the surface of the earth
magma: hot, liquid rock formed deep inside the earth

4. Rock Review

5. IGNEOUS ROCKS SEDIMENTARY ROCKS METAMORPHIC ROCKS
a rock is made of two or more minerals.
ROCKS ARE DIVIDED INTO THREE GROUPS BASED ON HOW THE ROCKS FORMED
IGNEOUS ROCKS
SEDIMENTARY ROCKS
METAMORPHIC ROCKS

6. hOW ARE rOCKS fORMED?
Today we will be using the rock formation chart to help us understand the formation and location of igneous rocks.
Materials:
red and orange crayon
pencil
formation chart
save chart for other lessons to follow. Only complete the parts indicated in this lesson.

7. Igneous rocks
Igneous rocks or fire rocks are formed from hot, molten materials called magma.  They can be found where volcanoes have or do exist.
Magma is is found beneath the earth’s surface.

8. Igneous rocks
Igneous rocks are created when molten rock (lava) inside the Earth pushes through the crust (like in a volcanic eruption) and then cools

9. Intrusive (plutonic) Igneous Rocks
Color the magma orange, stop before reaching the earth’s surface.
Intrusive rocks are made when magma that is blocked from reaching the earth’s surface cools slowly below the earth’s surface. Intrusive igneous rocks cool slowly deep within the earth and produces large crystals.
picture from
click here for more examples

10. intrusive igneous Rocks
QUARTZ
GRANITE
GABBRO
The slow-cooling process creates large crystals and appear coarse-grained. Some examples of these are:

11. Extrusive (volcanic) igneous rocks
Lava is the name for liquid magma that reaches the earth’s surface by flowing out of volcanoes.
The lava cools rapidly forming extrusive rocks which have small, fine grained crystals or glassy appearance.
Color the lave red
click here for more examples

12. EXTRUSIVE igneous Rocks
OBSIDIAN
PUMICE
BASALT
If gas bubbles are trapped as the lava rapidly cools a vesicular texture may occur
is a fine-grained, dark-colored extrusive igneous rock
If the cooling is instantaneous a glassy texture may form

13. Igneous Rock Video

14. Review With a partner and your chart explain:
How igneous rocks are formed
What magma is and where it can be found
What lava is and where it can be found
Intrusive and extrusive rocks