Igneous Rocks Notes

Igneous: 'Born of fire'

Magma: Very to molten rock and less dense than the surrounding rock

Lava: When magma reaches the surface

Formation of igneous rock: When magma or lava cools and solidifies

Extrusive igneous rocks: Rocks formed near the surface of the earth

Intrusive rocks: Rocks formed when magma cools below the earth's surface

Interlocking mineral crystals: Join together like pieces of jigsaw and produce hard rock

Classification of igneous rocks:

Texture

Colour

Texture: how soft or rough a rock is

Colour: How dark or light a rock is

Intrusive igneous contain large crystals due to magma cooling slowly

Examples of igneous rocks

Basalt

Dolerite

Granite

scoria

Pumice

Obsidian

Igneous Rocks