Crystallisation of Magma

1. What difference is there between the composition of Lava and Magma?

	Magma contains dissolved gases and lava does not
	Magma is solid and lava is a liquid
	Lava is solid and magma is a gas

2. Which type of magma is most likely to erupt effusively from a shield volcano?

	Cool, viscous (sticky) magma
	Hot, runny magma
	Magma that has already partly crystallised below ground

3. An igneous rock that is fine-grained or glassy must have:

	Crystallised slowly
	Cooled rapidly after erupting from a volcano
	Formed deep underground

4. A sheet-like intrusion formed as magma pushes in between layers of rock is called:

5. A pyroclastic flow is formed when an explosive eruption produces a dense mixture of:

	Hot gases and volcanic ash (shattered rock and pumice)
	Water and volcanic ash
	Water and lava