1. Rock Concept Map

2. Igneous Rocks
ESRT page 6

4. 1. Igneous rocks form from the cooling and solidification of magma (melted rock)

5. LIQUID HOT MAGMA
2. Magma is a mixture of liquid rock, crystals, and gas
3. Magma is less dense than surrounding rocks, and will therefore move upward

6. B. Types of Igneous Rocks
1.The cooling rate of magma differs, causing the crystal size to also differ

7. a. intrusive igneous rocks
Forms by the slow cooling of magma underground
“IN” –trusive / “IN” the ground
Also known as PLUTONIC

8. Because underground cooling is SLOWER:
Rock crystals are LARGER & have a coarse texture

9. gabbro
pegmatite
granite

10. Granite Mineral Composition

11. b. Extrusive igneous rocks
Fast cooling of LAVA (magma that has reached earth’s surface)

12. Lava flows forming extrusive igneous rocks (obsidian)

14. Because the lava Cools QUICKLY (exposed to colder air), rock crystals are SMALL and rocks have a fine/glassy texture

16. Rate of Cooling Activity- DO NOT WRITE
When I say “Go” try to find other students in the class who have the same color that you have- PLEASE WALK!
When I say “Stop”, stop exactly where you are and do not move until I say “GO” again
What happened as I gave you a longer amount of time to find each other?

17. Pumice is an Extrusive Igneous Rock that is VESICULAR (has gas pockets). Because pumice formed so quickly, the rock formed around the pockets of gas, creating “holes” in the rock. This allows the rock to float in water because of its lower density

20. All light in color, low in density, made up of the same minerals, and felsic in composition…. What’s the difference? COOLING TIME!

21. -Rock texture is by SIGHT/SIZE, not by TOUCH
Key idea:
-The texture of the igneous rock is determined by the size, shape, and arrangement of the mineral crystals NOT if it is smooth or bumpy
-Rock texture is by SIGHT/SIZE, not by TOUCH

22. types of magma FELSIC MAGMA MAFIC MAGMA Light colored
Thick (high viscosity)
Contains high amounts of silica
Ex. Granite
MAFIC MAGMA
Dark colored
Thin (low viscosity)
Contains high amount of magnesium & iron
Ex. Basalt

24. Mafic or Felsic?

25. the “bells & whistles” for identifying an IGNEOUS rock
Obvious crystals in a random order
Glassy texture
Air pockets

26. Igneous Rock Video Watch the video and write down 3 notes