Name:_________________________________________ Date:
Period:_______ ASSIGN
PLATE TECTONICS REVIEW SHEET
1) Label the diagram to the right. Label it
with the four main layers of the earth. Also,
put a brief description of what that layers is
made of (i.e. cool rock, liquid metal)
1. Crust-Solid rock
2. Mantle- solid but it flows
3. Outer core- Liquid metal
4. Inner core- solid metal (iron)
2) What happens to the pressure,
temperature, and density as you go to the
center of the Earth?
It increases
3) What is the difference between the
lithosphere and the asthenosphere?
The lithosphere is solid rock that makes up the crust and the upper mantle. The
lithosphere “rides” on the asthenosphere which is made of rock that flows like putty.
4) What are tectonic plates (make sure you include what layer tectonic plates are made of)?
Tectonic plates are made out of crust – made out of both continental and oceanic crust.
They are slabs (pieces) of rock that move over the Earth. They are the lithosphere.
5) Continental or Oceanic Crust?
a) What type of crust is denser? Oceanic crust
b) What type is thicker? Continental crust
6) What is Continental Drift? What is the evidence for it?
Continental Drift is a theory made by Wegener. He thought that the Earth was once
joined together in a supercontinent called Pangaea. He could not explain HOW the plates
moved.
Evidence: Fossils- Mesosaurus fossils were found in Brazil and W. Africa.
Climate- Tropical plant fossils were found in Greenland, which suggests that
Greenland was once much closer to the equator.
Rocks- A type of limestone was found in the Appalachian mountains and the
Scottish highlands. Also, the same type of rock was found in Brazil and W. Africa.
7) What is the theory of plate tectonics? What is the evidence for it?
It states that the Earth’s crust is separated into pieces and that they constantly move. By
moving towards each other, away from each other, or past each other, the plates cause
things like earthquakes, volcanoes, and mountains.
8) Label the plate boundary type below. State what happens to the plates at each of these boundaries.
Plates scrape past each other
Nothing is created or destroyed
Plates pull apart. New Crust is
formed.
Plates push together
Crust is destroyed.
Match the following descriptions to the plate boundary that they best describe. If the description best illustrates
a divergent boundary, put a D. Convergent=C. Transform = T.
__C____ 9) crust is destroyed or folded
___D___ 15) new crust is formed
__T____ 10) crust is neither created nor destroyed
__T____ 16) plates scrape past each other
__C____ 11) plates push together
__D____ 17) plates pull apart
__D____ 12) responsible for sea-floor spreading
__C____ 18) forms mountains
__C____ 13) where subduction happens
__D____ 19) creates rift valleys
__T___ 14) earthquakes common, no volcanoes
__C_____ 20) forms deep ocean trenches
__D____ 20b) Forms mid-ocean ridges
21)
a) What is subduction?
When one plate sinks under another plate
b) What plate boundary type (convergent, divergent, transform) is subduction associated with?
Where does Subduction occur?
It is associated with convergent boundaries (O-O and O-C). It occurs at subduction zones.
22)
Match the following descriptions to the plate boundary they best describe. Choices are CC (for
Continental – Continental Collision; OC (for Oceanic –Continental Subduction); OO (for OceanicOceanic subduction); D (for Divergent boundary); and T (for Transform). You may circle more than one
answer. The answers will be bolded.
a) causes earthquakes
b) causes volcanoes
c) causes mountains
d) causes ocean ridges and rift valleys
e) causes deep ocean trenches
f) causes island arcs
g) causes two plates to fold
h) causes one plate to subduct
23)
CC
CC
CC
CC
CC
CC
CC
CC
OC
OC
OC
OC
OC
OC
OC
OC
OO
OO
OO
OO
OO
OO
OO
OO
D
D
D
D
D
D
D
D
T
T
T
T
T
T
T
T
In the Ring of Fire, there are tons of active volcanoes, earthquakes, and deep-ocean trenches.
Explain why this place is so geologically active.
The “ring of fire” is the plate boundary of the Pacific plate. All plate boundaries are active
and move. This is the largest plate boundary and has over 500 active volcanoes.
24)
Hawaii is believed to be a chain of islands made of Hot Spots. What is a hot spot volcano?
You do not have to answer this question.
25)
When you look at a map of earthquakes and volcanoes happening around the world, where are the
majority of the earthquakes and volcanoes happening? Why?
Earthquakes and volcanoes occur at plate boundaries because magma can rise to the surface
of the Earth in those places. Also, pressure is high at the boundaries, especially when pieces of rock
get stuck against each other. When those rocks release, an earthquake occurs.
26)
How do scientists believe the plates are moving (even if it is only 2.5 centimeters a year)? What
part of the Earth’s layers do these happen in?
Plates move because they “ride” on the asthenosphere. The asthenosphere moves because of its
convection current. Magma heated at the bottom rises to the top where it slightly cools and
sinks.
NOTE: Make sure you explain the significance of the Mariana Trench, Mid-Atlantic Ridge, Iceland,
Great Rift Valley, and Himalayas.
Mariana Trench: Largest trench in the world. Philippine plate is subducting under the Pacific
plate. Is a Oceanic-Oceanic Convergent plate boundary
Mid-Atlantic Ridge: Largest mid-ocean ridge. Caused by a divergent plate boundary between the
North American and Eurasian plates. Spreads at an average rate of 2.5cm/year
Iceland: The only place that has a divergent boundary on land. The country is being split by the
Mid-Atlantic Ridge.
Great Rift Valley (or East African Rift): This is where the African plate is being split apart. It is
splitting into 2 plates. Currently Lake Victoria is in the Rift Valley. It will continue to spread until
it splits into the Nubian and Somalian plates.
Himalayas: The largest mountain range. It is caused by the continental-continental convergent
boundary between the Indian and Eurasian plates.