What are plates?
Pieces of the Earth's crust
What happens at a divergent boundary?
Plates move apart
What happens at a convergent boundary?
Plates move together
What happens at transform boundaries?
Plates slip past one another
What does the theory of plate tectonics state?
Earth's plates are in slow, constant motion driven by convection currents in the mantle
How much do plates move in a year?
About 1-12 cm
What is a fault?
A break in the Earth's crust where rocks have slipped past each other
What causes plates to move?
Convection currents in the mantle
What is convection?
The cycling of material due to changes in density caused by changes in temperature
Where do most divergent boundaries occur?
Mid-ocean ridges
When pieces of Earth's crust diverge on land, what landform forms?
Rift valley
What happens at convergent boundaries between continental crust and oceanic crust?
The more dense oceanic crust sinks beneath the less dense continental crust
What happens when two plates carrying continental crust collide?
Mountain ranges are formed
What can occur when two plates suddenly slip past each other at a transform boundary?
Earthquakes
