Understanding Volcanoes
We have just finished a lab called Krakatoa. You should have some idea as to why that particular volcano erupted the way it did. We will take a closer look at Krakatoa and get a better picture.
Krakatoa
is (or was) located in
http://www.worldatlas.com/webimage/countrys/asia/idlarge.htm
Krakatoa cannot be seen here, but it would be somewhere near the letter g in Bandarlampung (lower left hand corner).
Scroll down below the map to where it says Brief Discussion. Keep scrolling down until you see Land Statistics.
How many volcanoes are there in
How many are active?
Click on the number of volcanoes. Describe how the pattern of volcanoes.
Go back to the last page where
you just were. Click
on Ring of Fire. You will see
that
Which two plates are hitting each
other in
Go to the following website:
http://www.classzone.com/books/earth_science/terc/content/visualizations/es0902/es0902page01.cfm
Click on the picture and describe what you see.
Why does a volcano form here? (What happens to some of the melting oceanic crust?)
Not all volcanoes form this
way.
Go to the following webpage to see a map of the East African Rift Valley.
http://stloe.most.go.th/html/lo_index/LOcanada4/403/html/2_2en.htm
Look at the picture. Which sea is getting wider as these plates move apart?
Another way for a volcano to form
is from a Hot Spot. The
Go to the website below to see a
map of the
http://volcano.und.edu/vwdocs/volc_images/north_america/hawaii/hawaii.html
Notice how all of the volcanoes
are in a line.
Even though all of the islands
are volcanoes, only the
.
http://www.windows.ucar.edu/tour/link=/earth/interior/plume_volcanism.html
Describe what a hot spot is:
Look at the animated
picture. Describe why
Now let’s see why exactly different volcanoes erupt differently.
Go to http://dsc.discovery.com/convergence/pompeii/interactive/interactive.html
On the menu, choose Volcano types. See the choices in the lower right hand corner. Which type was not mentioned in your book?
What does your book call this type of volcano?
The eruption has something to do with the magma type, especially if it is viscous or not.
What does viscous mean? You may need a dictionary here!
Click on Build your own volcano. What two factors affect the shape and explosiveness of volcanoes the most?
What conditions do you need to make a shield volcano?
What conditions do you need to make a stratovolcano?