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Question 1

What’s the difference between magma and lava?

Answer 1

When a volcano erupts, the resulting explosion shoots this magma out into the atmosphere. At this point the magma becomes known as lava. There is no major difference between magma and lava – the terms merely distinguish whether the molten rock is beneath or above the surface. Magma is composed of molten rock and is stored in the Earth’s crust. Lava is magma that reaches the surface of our planet through a volcano vent.

Question 2

Why do volcanoes often have lava domes?

Answer 2

Lava domes are formed by viscous magma being erupted onto the surface and then piling up around the vent.

Question 3

Why do volcanoes form along convergent plate boundaries?

Answer 3

If two tectonic plates collide, they form a convergent plate boundary. At diverging plate boundaries, earthquakes occur as the plates pull away from each other. Volcanoes also form as magma rises upward from the underlying mantle along the gap between the two plates.