Vocabulary
Who discovered that Earth used to be 1 big piece of land and then broke apart?
Alfred Wegener
The boundary where plates move away from each other.
Divergent boundary
This is created when ocean-continent boundaries converge:
trench / volcanic arc
The most common reason that plates move
Convection currents
When magma reaches the surface it is called
lava
What was the giant piece of land called?
Pangaea
The boundary where plates move towards each other.
Convergent boundary
This happens when ocean-ocean boundaries diverge:
Seafloor spreading
This occurs when the weight of an elevated ridge pushes an oceanic plate out toward a subduction zone
ridge push
The Earth's layer that is between the crust and the core.
Mantle
What is the outer layer of the Earth that moves called?
The boundary where plates slide against each other.
Transform boundary
These are created when continental-continental boundaries converge:
Mountains
This occurs as the weight of the subducting plate pulls the trailing lithosphere into a subduction zone.
Slab pull
What is the name of the famous transform boundary in California?
San Andreas Fault
Where 2 plates meet
plate boundaries
The type of boundary that creates new crust
Divergent boundary
This is created when continental-continental boundaries diverge:
Rift Valley
When 1 plate moves below another plate because it is older and denser
How many tectonic plates are there?
15 total: 7 major and 8 minor
(I will accept 15 or 7)
4 pieces of evidence that Pangaea existed:
-The pieces look like they fit together
-Fossil evidence
-Rock match
-Climate evidence (coal and glacial deposits)
The 3 types of convergent boundaries
Ocean-Ocean
Ocean-Continent
Continent-Continent
This is the result of 2 plates in rubbing back and forth together in the ocean (transform boundary)
Tsunami
Sometimes there is a 4th reason the plates move, but we didn't learn much about it. This is called
Trench suction
What is Alfred Wegener's theory called
Continental Drift Theory