Subduction
The PROCESS when one plate is pushed underneath another plate
Destructive plate margin
Where 2 plates collide and one plate sinks under another, destroying the oceanic crust
Constructive Plate margin
Where the two plates move apart making new crust
Conservative plate margin
Where 2 plates slide alongside each other at different speeds, stick slip occurs which causes earthquakes
Crust
The outer, solid layer of the Earth
Mantle
The layer of the earth between the crust and the core, molten in parts
Convection current
The movement of magma in the mantle caused by heating of the material
Inner Core
A dense sphere of solid iron and nickel at the center of Earth
Plate Margin
Where the two plates meet
Continental crust
Granitic part of the Earth's crust that makes up the continents. Continental crust is also called sial because it consists largely of silica and aluminum and averages about 40km thick
Oceanic crust
Thin, more dense than continental crust, subducting crust
Fold mountains
These are mountains formed as the plates move together and folds are formed as the the layers are squeezed horizontally.
Ocean Trench
Deep valley in the ocean floor that forms along a subduction zone
Ocean ridge
Created at a divergent boundary where the ocean plates spread apart. Magma rises out to form underwater mountains.
Composite volcano
Tall, cone-shaped volcano in which layers of lava alternate with layers of ash
Shield Volcano
A wide gentle sloping volcano made of layers of lava and formed by quiet eruptions.
Pacific ring of fire
Zone of crustal instability, volcanism, and earthquakes in the Pacific region.