Unit 8: The Movers and Shakers

What is a volcano?

• A weak spot in Earth’s crust where magma can come to the surface.

• A mix of rocks, minerals, gases, and water from the mantle.

• Hot semifluid rock that becomes solid rock as it cools off.

• A special kind of mountain.

What is magma?

• Hot semifluid rock that becomes solid rock as it cools off.

• A mix of rocks, minerals, gases, and water from the mantle.

• A weak spot in Earth’s crust where magma can come to the surface.

• Hardened rock.

What is lava?

• A weak spot in Earth’s crust where magma can come to the surface.

• A mix of rocks, minerals, gases, and water from the mantle.

• Hot semifluid rock that becomes solid rock as it cools off.

• A really hot part of the mantle.

Where do volcanoes typically form?

• At plate boundaries.

• In the middle of tectonic plates.

What is an active volcano?

• A volcano that has erupted at least once in the last 10,000 years.

• A volcano that hasn’t erupted in the last 10,000 years, but could still erupt.

• A volcano that should never erupt again.

What is a dormant volcano?

• A volcano that has erupted at least once in the last 10,000 years.

• A volcano that hasn’t erupted in the last 10,000 years, but could still erupt.

• A volcano that should never erupt again.

When a volcano erupts, empties the magma chamber, and collapses the top leaving a huge hole.

• Dike
• Caldera
• Silica
• Geyser

Inside a volcano, magma collects in a pocket called a:

• caldera
• pipe
• magma chamber
• vent

Magma's resistance to flow, or how thick it is, is called:

• silica
• viscosity
• hot spot
• caldera

This type of volcano has explosive eruptions that result in massive amounts of tephra (ash).

• Shield volcano
• Composite / Stratovolcano
• Cinder cone
• Fissure volcano