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Forecasting an Eruption Student Worksheet
1.	For both Scenarios 1 and 2, choose which statement best describes the seismicity from the options below.

SCENARIO 1	SCENARIO 2	
•	Seismicity at the volcano is at a very low level.
•	Seismicity at the volcano is at an elevated level, with many deep earthquakes.
•	Seismicity at the volcano is at an elevated level, with many shallow earthquakes.	•	Seismicity at the volcano is at a very low level.
•	Seismicity at the volcano is at an elevated level, with many deep earthquakes.
•	Seismicity at the volcano is at an elevated level, with many shallow earthquakes.	
2.	For both Scenarios 1 and 2, choose which statement best describes the deformation using the options below.
SCENARIO 1	SCENARIO 2	
•	No deformation is occurring at the volcano.  There is no change in tilt.
•	Deformation at the volcano is at a low level, with a gradual increase in tilt.
•	Deformation at the volcano is at a low level, with a gradual decrease in tilt.
•	Deformation at the volcano is at an elevated level, with a rapid increase in tilt.
•	Deformation at the volcano is at an elevated level, with a rapid decrease in tilt.	•	No deformation is occurring at the volcano.  There is no change in tilt.
•	Deformation at the volcano is at a low level, with a gradual increase in tilt.
•	Deformation at the volcano is at a low level, with a gradual decrease in tilt.
•	Deformation at the volcano is at an elevated level, with a rapid increase in tilt.
•	Deformation at the volcano is at an elevated level, with a rapid decrease in tilt.	
3.	For both Scenarios 1 and 2, choose which statement best describes the sulphur dioxide emissions using the options below.
SCENARIO 1	SCENARIO 2	
•	SO2 measurements indicate a low level of gas flux.
•	SO2 measurements indicate an elevated level of gas flux.	•	SO2 measurements indicate a low level of gas flux.
•	SO2 measurements indicate an elevated level of gas flux.	

4.	Which of the two time periods (Scenario 1 or 2) shows more signs of approaching eruptive activity? Justify your answer using information from the seismicity, deformation, and gas monitoring graphs. _______________________________________________________________________
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5.	What is the current Volcano Alert Level at Mount St. Helens?
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6.	Find a volcano that is not currently at the normal level. List the name, Alert Level, and color code of this volcano.
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7.	What Volcano Alert Level would you recommend assigning to the volcano for a) Scenario 1 and b) Scenario 2? Justify your choice for the Alert Level for both using what you know about the monitoring data.
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8.	Using what you learned in the slideshows above, draw lines to match the name of a hazard, a description of the hazard, and what areas the hazard affects.
HAZARD	DESCRIPTION	WHERE IT AFFECTS	

A slurry of water mixed with volcanic ash and rocks, which is often described as having the consistency of wet cement.

It typically stays within valleys downstream of the volcano or can spread across low-lying flat areas.

Pyroclastic Flow

The general term for pieces of rock and ash blown apart by an explosive volcanic eruption.

It travels in valleys but it can sometimes go up and over tall ridges.

Tephra

An extremely hot, swiftly-moving flow of volcanic ash and rock suspended in gas.

It travels high in the atmosphere, affecting areas downwind of the volcano.

Lahar

9.	Find the town of Toutle, Washington. What type or types of volcanic hazards might affect the people in Toutle?
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10.	What would you recommend that emergency response officials say to the people in Toutle so that they can remain safe from volcanic hazards?
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