3.1. Magmatic rocks
Magmatic or igneous rocks are formed as a result
of the cooling and solidification of magma.
Magma is the melted rocky material formed below
the Earth's crust or mantle.
There are two types of igneous rocks:
- Plutonic (intrusive) rocks
They form as magma cools slowly under the ground
over thousands of years.
As a result, the mineral crystals are large and well done.
- Volcanic (extrusive) rocks
They form as lava cools rapidly on the surface of the Earth.
As a result, the mineral crystals are tiny.
READING ACTIVITIES
After reading the text, copy and answer the following questions into your notebook:
Remember: you must make complete sentences.
3.4. What is the difference
between:
a. plutonic or intrusive rocks and volcanic or extrusive rocks
b. magma and lava
3.5. In which type of magmatic rock can you see mineral most clearly?
Why?