Due to extreme heat in the interior of the earth, rocks are found in the form of molten material called magma.
When magma comes out on the surface of the earth, it cools down and turns into solid rocks. Such rocks are termed as extrusive rocks. Examples: ★ Basalt. ★ Deccan Trap is built of basalt.
When the molten magma cools down within the interior of the earth, it becomes solid to form intrusive rocks. Examples: ★ Granite. ★ Gabro.
