🪨 Igneous Rocks: Formation and Characteristics
Discover how igneous rocks form when hot magma and lava cool and solidify deep beneath Earth's surface and on the surface. Learn the difference between intrusive and extrusive rocks, how cooling rate affects crystal size, and identify common igneous rocks like granite and basalt. **What you'll learn:** - How magma and lava cool to form igneous rocks - The difference between intrusive and extrusive igneous rocks - Why cooling rate affects crystal size and texture - How to identify common igneous rocks - The relationship between formation location and rock characteristics
Questions in this quiz
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- Question 1
What is magma?
- Question 2
Lava is the same thing as magma.
- Question 3
Which type of igneous rock forms when magma cools slowly underground?
- Question 4
What is granite?
- Question 5
How does slow cooling affect the crystals in igneous rock?
- Question 6
Basalt is an example of an extrusive igneous rock.
- Question 7
What type of igneous rock forms when lava cools quickly on Earth's surface?
- Question 8
Why do extrusive igneous rocks have smaller crystals than intrusive igneous rocks?
- Question 9
Which of the following is an example of an intrusive igneous rock?
- Question 10
You can see large crystals in basalt with just your eyes.
- Question 11
What happens to magma when it cools and solidifies?
- Question 12
Where do intrusive igneous rocks form?
- Question 13
All igneous rocks are formed from the cooling and solidification of magma or lava.
- Question 14
Which cooling rate produces igneous rocks with fine-grained texture?
- Question 15
What is the relationship between crystal size and cooling rate in igneous rocks?
- Question 16
Obsidian is an extrusive igneous rock that forms from very rapid cooling of lava.
- Question 17
How can you tell if an igneous rock is intrusive or extrusive by looking at it?