Volcanoes 2020

What is molten rock that has formed deep within the Earth?

• Cinders

• Magma

• Lava

• Volcano

What is molten rock that has reached the Earth's surface?

• Cinders

• Lava

• Magma

• Hot spot

What determines if an eruption will be explosive?

• The amount of gases in the magma

• The amount of silica in the magma

• The amount of gas and silica in the magma

• None of these affect the explosiveness of the volcano

Vocanoes are found...

• on land
• under water
• on islands
• all of the above

What is a volcano?

• A mountain that has lava all over it 
• A giant hill filled with magma
• A long high sea wave 
• A hole in the Earth where magma erupts

The difference between magma and lava is _____

• where it is found (above or below the surface)
• how hot the molten rock is (lava is hotter than magma)
•  the type of boundary where it forms
• the viscosity of the molten rock (lava has a lower viscosity)

Where are most volcanoes found?

• Southern Hemisphere
• Ring of Fire
• Mid-Atlantic Ridge
• Hot Spots

__________ volcanoes are the largest with broad, gentle slopes and effusive eruptions.

• Cone

• Composite

• Angel

• Shield

A subduction zone is...

• plates pull apart.
• the continental plate slides under the oceanic plate.
• where the oceanic plate slides under the continental plate.
• plates slap each other a high five.

What is it called when an explosive eruption forms a dense, super-heated cloud of gas, ash, and lava that travels extremely fast.

• Lahar

• Lava

• Caldera

• Pyroclastic flow