2. Continental Drift Alfred Wegener developed the idea of continental driftAlfred Wegener developed the idea of continental drift Continental drift is the theory that continents can drift apart from one another and have done so in the pastContinental drift is the theory that continents can drift apart from one another and have done so in the past

3. Sea-Floor Spreading New oceanic lithosphere is created as older materials are pushed awayNew oceanic lithosphere is created as older materials are pushed away mid ocean ridge in the Atlantic oceanmid ocean ridge in the Atlantic ocean

5. Magnetic Reversals Earth’s magnetic poles changeEarth’s magnetic poles change Rock records the direction of Earth’s magnetic fieldRock records the direction of Earth’s magnetic field

7. Plate Motion Ridge Push – oceanic plate slides downwardRidge Push – oceanic plate slides downward Convection – hot material rises and cooler material sinksConvection – hot material rises and cooler material sinks

8. Plate Motion (cont.) Slab Pull – the sinking oceanic plate sinks and pull the rest of the plate with itSlab Pull – the sinking oceanic plate sinks and pull the rest of the plate with it

11. Convergent Boundary Occurs when two tectonic plates push into each otherOccurs when two tectonic plates push into each other Continental-Continental: MountainsContinental-Continental: Mountains Continental-Oceanic and Oceanic-Oceanic: SubductionContinental-Oceanic and Oceanic-Oceanic: Subduction

15. Divergent Boundary When two tectonic plates move away from each otherWhen two tectonic plates move away from each other mid-atlantic ridgemid-atlantic ridge

16. Transform Boundary When two tectonic plates slide past one anotherWhen two tectonic plates slide past one another San AndreasSan AndreasFault