Volcanoes

Key Terms

• Magma Lahar• Volcanism Pyroclastic flow• Lava• Volcano• Hot spot• Mafic• Felsic• Pyroclastic material• Caldera

Volcanoes and Earth’s Spheres

• Provide a picture and written description of how volcanoes can affect each of Earth’s spheres.

• ONE picture and ONE description for each sphere.

Major Volcanic Zones

Ring of Fire

Major Volcanic Zones

• Subduction Zones• Mid-Ocean Ridges• Hot Spots

Subduction ZonesVolcanoes

Mid-Ocean RidgeVolcanoes

Hot SpotsVolcanoes

Key Questions

• Describe THREE conditions that affect whether magma forms.

• Explain how magma reaches Earth’s surface.• Summarize the formation of hot spots.

The Hawaiian-Emperor Seamont Chain

• The following map shows the locations and ages of islands and seamounts in the Hawaiian-Emperor seamount chain, which is located in the Pacific Ocean. Use the map to answer the questions that follow.

The Hawaiian-Emperor Seamont Chain

The Hawaiian-Emperor Seamont Chain

The Hawaiian-Emperor Seamount Chain

• Which volcano is the oldest?• A seamount is a submarine volcanic mountain. Would you expect

older volcanoes to be seamounts or islands? Explain your answer.• Which island signifies a change in direction of the movement of

the Pacific Plate?• In which direction has the Pacific Plate been moving since the

formation of the Islands in the seamount chain changed direction?

• How many years ago did the Pacific Plate change its direction?• The Pacific Plate has moved 3220 km since the seamount

changed directions. What is the average speed of the Pacific Plate over that time?

Volcanic Hazards

• List and Describe possible hazards associated with volcanic eruptions to nearby populations.

• On day 1, a volcano expelled 5 metric tons of sulfur dioxide. On day 2, the same volcano expelled 12 metric tons of sulfur dioxide. What is the percentage increase in sulfur dioxide expelled from day 1 to day 2?

• What are the effects of increased levels of sulfur dioxide in the atmosphere?