Name___________________________
Period______________________
Earth Science
Unit 3: Plate Tectonics and Earth’s Structure
Chapter 10: Volcanoes
Directions: Complete each section of the Study Guide as it is assigned. Mark with a check to
indicate you have finished each part. If you are not able to complete the section assigned in
class, complete it for homework so you are ready to begin the next section in class.
Section 10.2 Where Do You Find Volcanoes? (Assigned:_______Due:_________)
____Read pages 209 - 213 in your text.
____Complete the study session.
____Copy/color Figure 10.6 page 210
____Add the vocabulary words to the vocabulary book
____Use the “Island arcs are features near plate boundaries” on page 212. Add to the thinking
map along with the illustration.
____Complete the 10.2 Section Review on page 214
Study Session: Where Do You Find Volcanoes?
I. Volcanoes at plate boundaries
A. Where are most volcanoes found?
1. Volcanoes are located __________________________________.
2. About ______of the active volcanoes occur along the shores of
___________________________.
B. Ring of Fire
1. The _________________coincides with regions where the oceanic crust of
the ___________________subduct under other plates.
2. _____________________ is one of the volcanoes within the Ring of Fire.
3. Mount St. Helens formed when the small _______________Plate subducted
under the ____________________________.
4. The elevation of Mt. St. Helens was __________meters before the eruption
and______meters after.
II. Volcanoes at mid-ocean ridges
A. Pressure decreases at mid-ocean ridges
1. Mid-ocean rides occur at _______________________________.
2. _______________currents in the lower mantle pull the plates away.
3. As the plates move apart, __________________material is drawn toward
Earth’s surface.
4. The rock of the ____________is _________, ___________, and
____________.
5. The rock is solid
because___________________________________________.
6. As the rock of the ________________rises, the pressure
________________and the material melts.
B. Basalt and silica
1. The melted lower mantle material forms __________________.
2. Basalt is __________________________________.
3. ______________makes magma thick and sticky.
4. Basalt magma is runny because____________________________.
5. ______________is a mineral that is made of silica
C. Runny Lava
1. When runny basalt lava oozes out at a ______________, it hits
_________________
2. Sea water cools the lava forming a ___________ but the crust cracks
and ______________________________________.
3. This repeats over and over forming lava that looks like
_____________________.
4. The presence of pillow lava can be a clue for __________________
___________________________________.
III. Volcanic chains
A. Away from plate boundaries
1. A ______________________is not formed at a plate boundary.
2. It forms as a result of ____________________that bring material from
deep in the mantle.
3. Magma of both _____________ and _____________ forms as hot but
sold rock and moves toward ______________________.
4. The melted lower mantle material forms __________________that is
less dense than______________________.
5. As the hot rock rises, _________________, and the rock melts to form
___________________.
B. A volcanic island is born
1. The basalt magma melts its way through the
______________________.
2. An __________________forms when magma breaks through the
surface.
3. Magma will form a ___________________if the eruption is strong
enough.
C. Volcanic island chains
1. The plate on which the volcanic island sits is _______________, but the
mantle plumes ________________________.
2. The top of a mantle plume is called a _____________________.
3. As the plate moves, the ____________________is carried away from
the hot spot.
4. The volcano becomes extinct when ___________________________.
5. The hot spot begins to _______________________________.
6. An _________________________is formed in this manner.
7. The hot spot under the island of Hawaii has formed the
_____________________and__________________ volcanoes on the
island.
8. The hot spot is currently making the undersea volcano, ____________
IV. Using island chains to measure the motion of a plate
A. The Hawaiian Islands
1. The Hawaiian Islands are an example of __________________________
2. Hawaii has been on top a hot spot for _______________________.
3. The islands to the northwest of Hawaii are _______________and their
volcanoes are either ______________or_______________.
B. Island chains and the speed of plates
1. By studying the
_______________,_____________and_______________of a volcanic
chain, scientists can determine the ___________ and
_____________that a plate is moving
2. The Hawaiian Chain is moving about ___________per year.
V. Volcanoes at subduction zones
A. What happens when a plate subducts?
1. A subducting plate bends and passes under a
_________________________.
2. As it sinks into the mantle, _________and__________ are carried
along and ______________is released.
3. The combination of ________and___________allows the rock to melt
at a lower temperature so the magma is ____________than the
surrounding rock and it rises.
4. Magma melts through the edge of the overlying plate forming
_______________.
B. Thick and sticky magma
1. Magma that forms volcanoes is rich in _______________.
2. The famous granite domes of ______________________ were formed
as magma rose through the edge of the _________________ plate.
C. Granite is silica-rich
1. Continents are made of ____________________.
2. Granite is not as dense as ________________________________.
3. This is why ____________________________________________.
4. They stand above the oceans and provide us with _______________.