This Earth Science video looks at how different types of volcanic eruptions produce different types of volcanic rocks. We use the term Igneous to describe all rocks that are formed from magma in the Earth's mantle. The term Tephra is used to describe all types of pyroclastic materials, regardless of size, whether that be ash, rocks, or lava bombs.
Types of magma are determined by chemical composition of the magma. Three general types are recognized: Ryholite, Andesite and Basalt.
This video was made in New Zealand.