Information about Geology 8T Quiz 5

This quiz is about volcanoes, magma, volcanic eruptions, and volcanic hazards. Be sure to read the background information about volcanic eruptions on p.154-156, look over the answers you gave to lava X and lava Y activities, and read through the lab notes for week 6. The classroom should be open at least an hour before class begins and the flyers that you made about each hazard will be out in the back of the room if you want to look at them before the quiz.

The images used for the lava viscosity and volcanic gas worksheets are posted on SacCT along with a pdf of the powerpoint for this lab (click on 'pdf documents' in the left side bar on the SacCT 8T website).

I will choose 3 of the following questions:

1. Explain what viscosity is.
   
   Fill out the table below:
   
   

   Magma Viscosity	Eruption type (peaceful or explosive)	One type of volcano tha forms from this type of magma	Rock that forms from this magma
   LOW
   HIGH

   
   
2. What kind of magma is most likely to create an explosive eruption and why?
   
   

   Magma type most likely to create and explosive eruption	This magma type is most likely to create an explose eruption because:

   
   
   
3. 
   

   The major component of magma/lava that affects viscosity is:
   Describe the difference between a low viscosity lava flow a high viscosity lava flow.	How much of the major component you named above is in low viscosity magma relative to that of high viscosity magma?

   
   
4. How do calderas like the Long Valley Caldera form?
   
   
5. What causes earthquakes in the Long Valley region?
   
   
6. What is tephra? Name at least two dangers associated with tephra.
   
   

   What is tephra?	Two dangers associated with tephra

   
   
7. What are pyroclastic flows and what makes them so dangerous?
   
   

   What are pyroclastic flows (describe them)?	Reasons why pyroclastiv flows are so dangerous

   
   
8. What kind of lava builds a lava dome and what kind of hazard is produced when a lava dome collapses?
   
   

   Lava/magma type that builds a lava dome	Hazard produced by lava dome collapse

   
   
9. What hazardous volcanic gas is causing the most problems in the Long Valley region and what kind of problems is it causing?
   
   

   The hazardous gas causing the most problems in Long Valley is:	Problems caused by this hazardous gas in the Long Valley area include: