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Vocabulary
Wegener's Theory
Divergent/Transform Boundaries
Convergent Boundary
Plate Tectonics
100
contienents slowly moved over Earth's surface
Continental drift
100
What evidence supported Wegener's theory?
1) land features 2) fossils 3) climate change
100
What do divergent boundaries do?
they move apart
100
What do convergent boundaries do?
They move together
100
What are the 3 boundaries?
1) divergent 2) convergent 3) transform
200
What is sea floor spreading?
it adds more crust to the ocean floor
200
Wegener hypothesized that........
all the continents were once joined together into a single landmass and have since drifted apart
200
Where do most divergent boundaries occur?
They occur along mid ocean ridges.
200
When 2 oceanic plates collide........
the denser plate sinks
200
What causes plate boundaries to move?
convection currents
300
supercontinent
Pangaea
300
In what year did he become curious about the continents?
1910
300
What do transform boundaries do?
They slip past eachother.
300
When an ocean plate collides with a continental plate, oceanic crust.....
pushes up the less dense continental crust
300
As the plates move, they produce earthquakes, _______, and mountain ranges.
volcanoes
400
What is subduction?
the process by which the ocean floor sinks beneath a deep ocean trench and back into the mantle
400
Why was Wegener's theory rejected?
Because he couldn't explain what forces were pulling and pushing the continents
400
When plates diverge onto land it can form ______ _______.
rift valleys
400
When 2 continental crusts collide....
mountain ranges form
400
During subduction, gravity pulls _________ plate edges downward into the mantle.
denser
500
long chains of mountains that rise up from the ocean floor
mid-ocean ridge
500
What kind of scientist was Wegener?
German Scientist
500
What occurs along transform boundaries?
earthquakes
500
Scientists use _________ to measure plate movement.
satellites