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9/11- Geo Engage
• Write down 3 characteristics of the United
States that you enjoy.
– Think about things that you can do here that you may
not be able to do in other countries.
Bell Ringer
Take out a sheet of paper, put your name on it.
Write your answer to the questions.
1. What type of tectonic activity made Hawaii?
2. What activity within the mantle causes plate
movement?
3. What type of erosion created the Great
Lakes?
4. What type of plate boundary is the San
Andreas fault in California.
5. What type of external force of change
carries away pieces of rock and creates
sediment?
Earth is composed
of 3 layers:
1. Core
2. Mantle
3. Crust
1. Core (inner &
outer) – made of
iron & nickel
a. inner – super
hot solid
b. outer – super
hot liquid
-temperatures can reach
8,000*F
2. Mantle
-hot, dense
mostly liquid
rock
-pockets of
magma (rise &
fall)
-made of
silicon,
aluminum,
iron,
magnesium,
and oxygen
3. Crust
-rocky shell
which forms
earth’s surface
-broken into
dozen slabs of
rock called plate
-these plates
carry oceans &
continents
-Continental Drift :
*super-continent
was called Pangaea
PANGEA
-Plate Tectonics – term to describe the
activities of continental drift and magma flow
which create many of Earth’s physical
features
*plates crash into each other, pull apart, or grind
and slide past each other (about 4 inches or
less per year)
-Why do plates move?
-convection currents
*hotter material is less
dense & rises (toward
crust of Earth)
*cooler material is more
dense & sinks (toward
core of Earth)
*creates continuous
circular
motion/movement
Why might a scientist want to study plate
tectonics?
Divergent Boundary
-Plates move apart (rift) from each other (tension)
1. Continental-Continental = creates gap (rift
valley) in which water can flow in
*ex: Red Sea; Great Rift Valley
2. Oceanic-Oceanic = magma rises up & creates
new crust on edges of the 2 plates
-enlarges the ocean floor & forms underwater
mountain ranges called ocean ridges
*example: Mid-Atlantic Ridge
Convergent Boundary
In general:
- Plates move
toward each
other & collide
(compression)
- One plate is
forced below
the other
(subduction)
1. Oceanic-Continental
-subduction occurs = heavier sea plate
dives beneath lighter continental plate
*sea plate begins to melt into magma 
pressure builds  magma bursts thru crust to
form volcanic mtns
*ex: Andes
Mountains
in S.
2. OceanicOceanic
-subduction
occurs
*sea plate
begins to melt &
magma rises to
ocean surface in
form of volcanic
islands
*example:
Philippine islands-
3. ContinentalContinental
-pressure builds
until one plate is
subducted
*sometimes sinking
plate melts & rises as
volcanic mountains are
formed
*example: Himalaya
mountains
Transform Boundary
-Plates slide past each other along faults
(cracks in the earth’s crust)
- Crust is pulled and stretched (tension) until
tension is released (Earthquake)
-example: San Andreas Fault in California
HOT SPOTS
-Magma rises thru
the tectonic plate
-The magma erupts
on the surface as
lava & hardens to
form volcanic islands
Animations
Hot Spot
Earthquakes &
Tsunamis
Guess the
Tectonic Activity!
Oceanic-Oceanic Convergent
Oceanic-Oceanic Divergent
Transform
Continental-Continental Convergent
Continental-Continental Divergent
Oceanic-Continental Convergent