1. Plate Tectonic Notes

2. C. Evidence to support theory 1. fossil records are similar on different continents 2. land forms such as mt. ranges and mineral deposits line up 3. coastlines of current continents appear to “fit together” like a puzzle I. Continental Drift Theory A. proposed by Alfred Wegener in 1912 B. states that all continents were once one supercontinent (Pangaea) and have since “floated” apart over time

3. II. Theory of Plate Tectonics A. states that the earth’s crust is broken into large moving pieces (plates) to which the continents are attached. B. evidence that supports this theory 1. sea-floor spreading 2. earthquakes and volcanoes 3. actual recorded movement

4. C. 16 plates (* means major plate) 1. N. American* 6. Arabian 11. Indo-Australia* 2. Eurasian* 7. Phillippine*12. Fiji 3. Juan De Fuca 8. S. American* 13. Nazca* 4. Caribbean 9. Caroline 14. Pacific* 5. Cocos 10. African*15. Scotia 16. Antarctic*

5. III. Plate Boundaries A. locations where two plates meet B. where the forces that shape the earth’s surface occur 1. Constructive forces – create landforms 2. Destructive forces – destroy landforms C. three different types

6. 1. Divergent a) plates move away from each other b) sea-floor spreading & ridges c) new crust is formed at this boundary type d) mid-Atlantic Ridge in Atlantic Ocean 2. Convergent a) plate move toward one another b) subduction- one plate forced underneath another > deep trenches, coastal mt. ranges, volcanoes > Andes Mts on west coast of S. America c) collision – both plates push upward c) collision – both plates push upward > large mt ranges, earthquakes > Himalaya mt range in northern India 3. Transform a) plates move past one another in different directions b) faults visible at surface, large earthquakes c) San Andres Fault in California

7. BoundaryMovementIllustrationResulting Landform(s) Divergent Boundary Plates move away from each other Sea-Floor Spreading New Crust Formed Example: Mid-Atlantic Ridge Convergent Subduction Convergent Collision 1 plate forced underneath the other Transform Boundary Plates move past each other Both plates collide and push upward Deep trenches, coastal mt ranges with volcanoes Example: Western Coast of S America Mountain ranges Mild Earthquakes Example: Himalayas in India Fault lines visible at surface Earthquakes Example: San Andreas Fault - CA

8. divergent boundary divergent boundary transform boundary transform boundary convergent / subduction convergent / subductionboundary convergent / collision convergent / collisionboundary