1. PLATE TECTONICS
A Moving Experience!!!

2. What is “Plate Tectonics”?
A theory that describe the formation, movements, and interactions of the earth’s tectonic plates
The plates ARE NOT the continents

3. Early Ideas Continental drift –developed by Alfred Wegener
The continents moved around
Shapes seemed to fit together
Similar fossils on separated continents
Rock formations matched up
Climate change evidence

4. Problems with Cont. Drift
How do the continents move? Why? What powers them?
Wegener only had a theory, but no supporting evidence.

5. Support of Plate Tectonics
Earthquakes and volcanoes seem to occur in a pattern
Magnetic evidence at the mid-ocean ridge
Chain of mountains at the mid-ocean ridge

6. Divergent Boundaries
Divergent boundary-plates move apart forming rift valleys
Sea floor spreading occurs at mid-ocean ridges

7. Convergent Boundaries
2 plates moving towards one another is a convergent boundary
When 1 plate is forced underneath another, subduction occurs, with the more dense plate going below the less dense plate (Subduction Boundary)
This often forms a deep-sea trench

9. Collision Boundary
2 continental plates smashing into one another forming one larger continent
The crust is forced upward resulting in a mountain chain
India crashing into Asia has caused the Himalaya Mountains

11. Transform Boundary
2 plates sliding past one another form a transform boundary
San Andreas Fault in California is a very active Transform Boundary

12. The Past in Plate Tectonics
Pangaea is the name given to the giant land mass when all the continents were together
Pangaea was around about 2.5 billion years ago