🪨 Igneous Rocks: Formation & Features
Explore how igneous rocks form when magma cools and solidifies beneath or above Earth's surface. Learn to distinguish between intrusive and extrusive igneous rocks, discover why crystal size varies, and identify common examples like granite and basalt. **What you'll learn:** - How magma transforms into solid igneous rock through cooling - The difference between intrusive rocks (slow cooling underground) and extrusive rocks (fast cooling above ground) - Why crystal size depends on cooling rate - Real-world examples of each rock type
Questions in this quiz
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- Question 1
What is magma?
- Question 2
Which type of igneous rock forms when magma cools slowly underground?
- Question 3
Granite is an example of an extrusive igneous rock that forms from fast cooling.
- Question 4
Why do intrusive igneous rocks have larger crystals than extrusive rocks?
- Question 5
Which of the following is a characteristic of basalt?
- Question 6
The cooling rate of magma affects the size of crystals in igneous rocks.
- Question 7
What happens to magma when it reaches Earth's surface and cools quickly?
- Question 8
Granite is a common intrusive igneous rock. Where and how does it form?
- Question 9
Extrusive igneous rocks form from lava that cools above Earth's surface.
- Question 10
Which process best describes how igneous rocks form?
- Question 11
If you examined two igneous rock samples under a magnifying glass and one had much larger crystals than the other, what could you infer?
- Question 12
Basalt typically has larger crystals than granite because basalt forms deeper underground.
- Question 13
Where would you most likely find intrusive igneous rocks like granite?
- Question 14
What is the relationship between magma cooling rate and crystal size in igneous rocks?
- Question 15
Pumice and obsidian are both extrusive igneous rocks that form from lava cooling at Earth's surface.