- The three types of volcano are composite, shield and dome.
- Magma is molten rock found under the Earth's surface, and lava is molten rock as it erupts from a volcano.
- The Volcanic Explosivity Index (VEI) is used to measure how much lava and ash is produced in an eruption.
- Earth's layers
5 things you didn't know
1. There are three types of volcano: composite, shield, and dome. Composite and dome volcanoes are usually conical, whereas shield volcanoes are wider and flatter.
2. Magma and lava are both names for molten rock – “magma” describes it beneath the Earth’s surface, and “lava” refers to the molten rock that flows (or explodes!) from a volcano.
Volcanic eruption with lightning
3. Volcanic eruptions can force huge amounts of electrically charged lava and ash into the air, causing a spectacular lightning storm to form during some eruptions.
Olympus Mons, on Mars
4. Olympus Mons on Mars is the largest volcano in the Solar System – it’s a mighty 27,000 metres tall, which is three times as tall as Mauna Kea in Hawaii, which is Earth’s biggest!
5. The Volcanic Explosivity Index (VEI) measures the lava and ash produced by a volcano, and how far it travels through the air. Each number on the scale is 10 times stronger than the one before it!
Spark a discussion
- What are the three different types of volcano?
- What is the difference between magma and lava?
- What does the Volcanic Explosivity Index measure?