Plate Tectonic Notes
Alfred Wegener born in 1880 German scientist proposed continents were
once together. He said…
• _____________________________________________________Pangaea
began breaking up & continents drifted to current locations. He gave this name:
________________________________________________________________________________________
________________________________________________________________________________________
He did research to come up with PROOF for this!
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A. 1st evidence ___________________________________________________.
He cut out _______________________________________________________
He called the great ocean ___________________________________________
The Great continent was called _______________________________________
________________________________________________________________
B. 2nd evidence __________________________________________________:
Found on the Following Continents:
– North Eastern N. America & Western Europe.
– ______________________________________________________________________
-- __________________________________________________________________________________
Every one of these places had matching rocks, But none of this was enough proof.
 C. 3rd evidence________________________ found all over the world:
• 1. East South America & West Africa.
• 2. ____________________________________ & ___________________________.
• 3. Northern North America and Europe.
D. 4th evidence Climate evidence
• 1. ______________________________________________ in Antarctica.
• 2. He found many identical fossils in climates opposite to what they would have
lived. SO… He began to develop . . .
Plate Tectonics
•
_________________________________________________________________________
_________________________________________________________________________
_________________________________________. (this movement driven by . . . )
He never found out, died on trek to Greenland in 1930
Years after his death in 1960s and 1970s
Plate Tectonics Truly Developed
Scientists discovered Convection currents – movement of partly molten rock in the Asthenosphere, driven by, heated,
rising material from mantle. The currents put friction on overlying layers of crust & cause plates to move.
Divergent Plate Boundaries
____________________________________ where 2 plates are
pulled apart. In this picture 2 ocean crusts.
•Here ______________________________________ rises up
through the ___________________________ toward surface,
causing the convection currents, ___________________________
•____________________________ -string of undersea divergent
boundaries where new ocean crust is formed.
•These are called spreading centers and are associated with
mountainous areas on the ocean floor called oceanic ridges.
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CONVERGENT BOUNDARIES HAVE 3 SUB – TYPES
•_________________________________________________ by
moving together. _______________________________________
area where an ocean plate dives or sinks under another ocean plate,
or continental plate.
•_________________________________________ and destroyed
here. Dives into the Asthenosphere melts then rises and circulates again.
•___________________________________________ are the most
common landforms. This is 2 Ocean crusts
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___________________________________________
___________________________________________
•The plates move toward each other.
•__________________________________ most
common landforms.
•Magma is generated at all subduction zones where dense oceanic
plates are pushed under lighter continental plates, melted, and
rises back up through the crust
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•This convergent boundary is where _______________
____________________________________________
•The ________________________________________
forming mountains. •The plates move toward each
other. ____________________________________ are
the common land forms
____
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TRANSFORM PLATE BOUNDARY
•This boundary ______________________________________ where
two plates slide past each other. _______________________
occur frequently at these boundaries. •The plates can move in same
direction but at different rates. ______________________________
shallow trenches are common. ANY TYPE OF CRUST transform
most common boundary.
_______________________________________________________
Causes of Plate Motion
1. _______________________________________________________.
– ___________________________________ from inside (e) to
surface. Hot ___________________________________ while cool
more dense rock material sinks.
2. This convection movement pulls plates along breaking &bending
them.
– ___________________________________________ at pulled apart
locations called ridges.
4. This makes new ocean crust.
5. At same time _____________________________ and melted at
subduction zones.
Growth and Change Continents
• Two ways continents grow
– ____________________________________________
– ____________________________________________
• Microplate Terranes- _______________________________________
___________________________________________________________
___________________________
Each Terrane has 3 characteristics:
– 1. _____________________________________________________
_____________________________________________________
– 2. ____________________________________________________
– 3. _____________________________________________________
_____________________________________________________.
• *California has 10 in the San Francisco Bay area