Mt. Saint Helens Location Expert (compositestratovolcano)
1. According to the Think-Quest web site, a basic volcano consists of five basic parts.
These basic parts are the _____________________, ______________________,
_______________________, __________________, and ___________________
_____________. (Link #1)
2. Hit the link that says “volcano” at the Think-Quest site; write down the definition of a
volcano. Be sure to write down the entire definition. (Link # 1)
Volcano:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
3. At the Think-Quest site (link#1), select the “Types of Volcanoes” button on the left-hand
bar. Volcanologists have classified volcanoes into groups based on the
________________, the _______________ they are built of, and the way the volcano
________________. (Link #1)
4. What makes a volcano erupt? Visit the Think Quest Volcano site to find this answer!
(Link #2)
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An eruption begins when ______________ on a ____________ __________
forces magma up through the conduit and out the volcano’s _______________.
When the magma chamber is completely __________________, the volcano
will erupt. The type of eruption partly depends on the amount of
_______________ and ________________ in the magma.
Read all about stratovolcanoes at the Think Quest web site! : (Link #3)
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Stratovolcanoes are also known as __________________ volcanoes.
Strato volcanoes are built by alternating layers of ____________ and ___________
fragments. This is why they are called __________________ .
Strato volcanoes often make massive snow-capped _____________.
Between eruptions they often seem _________________.
(Click on the word) Extinct means _________________________________________
______________________________________________________________________
Strato/composite volcanoes usually have ___________________ eruptions because the
main craterpipe gets clogged with _________________ until the gas backs up and causes
the explosive eruption.
© Eva La Mar 2000, 2004
www.geolit.org
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Strato/composite volcanoes are usually found along _______________zones.
5. Link # Why was Mt. Saint Helen’s eruption so famous? What made it unusual?
__________________________________________________________________________
__________________________________________________________________________
__________________________________________________________________________
6. Do strato volcanoes usually have big and explosive eruptions or does the lava just ooze
out of the top? (link #3)
__________________________________________________________________________
__________________________________________________________________________
7. Locate the names and locations of at least three strato volcanoes in the USA.. Pick an
American volcano, then pick “description” under “Background & Information”
(Link #5)
Volcano Name
Location (state/region,
country)
Elevation
1. Mt. Shasta
2.
3.
8. Select one of the volcanoes listed in number 7 and find the following facts: (Link#6)
Volcano Name
Elevation
Location
Last Eruption
I saved the image to:
Web Page Source
Address (citing
source)
9. Using a sheet of art paper, draw a diagram of a stratovolcano. Use the images from the
USGS that your teacher has run off for you. Be sure to show the LAYERS of lava, ash
and rock along the volcano’s steep sides. Be sure to label all parts of the volcano,
including the magma chamber, vent, crater, fissures, and, at least 2 layers of the lava, ash
and rock along the outside slope.
10. You can download a movie file of a Mt. St. Helen’s eruption to your PowerPoint
presentation, but you may only download one small file, and you must site the source
(name of movie, length of movie, photographer, and name of the site). You must have
this basic information written down before you may use the movie clip in your
presentation. You might need to download it on a computer that has a zip drive or save it
to a file on the desktop (it will be too large for a floppy disk. (Link #9)
© Eva La Mar 2000, 2004
www.geolit.org
© Eva La Mar 2000, 2004
www.geolit.org