1. ESS 125 – Volcanoes LAB
Volcano Scenario 6

2. 2 3 5 1 4 2 N Locations of pictures Contour line Rivers & streams
1000
2000 2
Locations of pictures
Contour line
Rivers & streams N
Major metropolitan area (city)
Logging forest
10 km
Suburbs (growing)
Contour interval = 1000 feet

3. 4 5 3 2 1
1000
2000
Numbers indicate locations of volcanic deposits (see following slides). N
10 km
Major roads
Contour interval = 1000 feet
Smaller roads
Small town or village

4. Volcano Scenario 6 – History of Eruptions
Large eruptions involving multiple hazards occurred about 13,000 years ago and about 6,000 years ago. For the past 2,900 years, only small eruptions have happened. The small eruptions involved the growth and collapse of lava domes with small lahars and pyroclastic flows at about 2900 and 2000 years ago, and again between years ago (multiple events).
In the most recent events, lahars and pyroclastic flows have traveled up to 15 km from the vent, but most are smaller. Ash from an eruption about 6,000 years ago can be found 100’s of kilometers away, and had a total volume beween km3. Most ash deposits are more localized, closer to the volcano.

5. View of volcano

6. Volcano Scenario 6: Identify Volcanic Deposits
Volcanic deposits (3 different deposits). Middle layer is about 2 feet thick. Location 1 on map.

7. Volcanic deposit. Location 2 on map.

8. Volcanic deposit along road at Location 4 on map
Volcanic deposit along road at Location 4 on map. hammer handle in center is about 40 cm long (about 16 inches)

9. Volcano Scenario 6: Identify Volcanic Deposits
Volcanic deposit. Location 3 on map. Largest block is about 1 foot across.

10. Volcanic deposit – location 3.
Note cracks radiating from the center of this block. This indicates a significant difference in temperature between the block (hot) and surrounding matrix (cold).

11. Volcanic deposit along road at Location 5
Volcanic deposit along road at Location 5. Close-up of this rock (below right).

12. Young volcano deposit near summit. Note small glaciers at summit.
Photo source: U.S. Geological Survey