1. Activity 37
Volcanic Landforms

2. Activity 37: Volcanic Landforms
Challenge  How do volcanic eruptions vary?
Key Vocabulary:
Magma
Model

3. In this activity we are going to use a model
In science, a model is a simplified representation of reality; they can be used to explain and predict natural processes.

4. All volcanic eruptions are the same?
Agree or Disagree?
All volcanic eruptions are the same?

5. Read the Introduction and define the term “Magma” in your notebooks.
Magma  hot liquid rock (Underground)

6. In your notebook, record the following data table:
Types of Eruption
Results
Less gassy “magma”
More gassy “magma”

7. Part A – Page D-10
Follow Steps 1-7 in your books. We are only going to have one “eruption” for each type! Pay attention.
Make sure to record your results in your notebooks

8. Part B Follow Steps 9-16 Again, make sure to record your results
Step 18: Compare the rocks and in your notebooks record which rock is more likely to be from the “more gassy” or “less gassy” magma. Explain your reasoning.

9. Lava Rocks:
BASALT
PUMICE
Less Gassy Magma:
More Gassy Magma:

10. Follow Up Discussion What do you think the rubber stopper represented?
Once magma erupts it is called lava
More gassy magma causes pressure to build up and often causes a more explosive eruption. This lava flows less smoothly

11. What caused the more gassy magma to explode so violently?
The chemical reaction of the baking soda and vinegar formed a gas
Because of the stopper the gas built up and created pressure
When the pressure was high enough the rubber stopper popped off
Volcanic eruptions are the result of building pressure, BUT the pressure is NOT a result of a chemical reaction as it is in the model.

12. Analysis Questions
In your notebooks, answer questions 1-3 and discuss your answers with your group

13. Analysis #1a Similarities Differences Less Gassy More Gassy
Chemical reaction resulted in “eruption”
Red bubbly lava
Released gas
Both caused magma and gases to form inside the model to be released
Gentle eruption with smooth flowing lava
Explosive eruption.

14. #1b
In general, the more gassy “magma” produced a more explosive eruption

15. #2
You would find both types (basalt and pumice) at Yucca Mountain because they had both types of eruptions

16. #3
If a volcano erupted many times over a period of years, you would expect a mountain to form.
As lava comes up and hardens, it forms new rock.
New rock builds up over time forming mountains.