1. PLATE TECTONICS

2. TEKS 8.9B relate plate tectonics to the formation of crustal features;
TEKS 6.10C identify the major tectonic plates
TEKS 6.10D describe how plate tectonics causes major geological events such as ocean basins, earthquakes, volcanic eruptions, and mountain building

3. What is Plate Tectonics?
Plate tectonics describes the means by which the oceanic and continental crust are able to move and the results of that motion.

4. The crust of Earth is divided into plates.
Key plates:
Eurasian
African
Indo-Australian
Pacific
Nazca
North American
South American

5. The plates are rigid and in constant motion relative to one another.

6. What Causes the Tectonic Plates to Move?

7. Intense heat from the core of the Earth causes convection cells to form in the asthenosphere.

8. The Earth’s continental and oceanic plates sit on the hot asthenosphere. While the rock in the asthenosphere is solid, it is less rigid than the plates, and therefore moves.

9. While scientists do not fully understand the forces that move the plates, it is believed that the moving material in the asthenosphere drags the plates along.

10. What Are the Results of Tectonic Plate Motion?

11. Each plate moves as a distinct unit
Each plate moves as a distinct unit. The borders between plates are called plate boundaries.

12. There are three different kinds of motion that occurs between the tectonic plates.
Divergent Plate Boundary
Transform Plate Boundary

13. I can out run the tectonic plates!
Even though the motion of the plates is very slow; about mm/year (this is about how fast your fingernails grow), the motion causes major geologic events and surface features.
I can out run the tectonic plates!

14. TRANSFORM Surface Feature: faults
Motion: plates grind past one another
Geologic Event:
earthquakes

15. San Andreas Fault
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16. DIVERGENT Surface Feature: Rifts
Rift valleys
Volcanic islands
mid-ocean ridge
Motion: plates move away from one another
Geologic Event:
new crust is formed
shallow earthquakes

17. rift valley
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Mid-Atlantic Ridge

18. CONVERGENT Geologic Event: Motion: plates move toward from one another
crust material is destroyed
earthquakes
volcanic eruptions
mountain building
Motion: plates move toward from one another

19. CONVERGENT Surface Features: volcanoes Island arcs Volcanic arcs
Trenches
Mountain ranges

20. Mount Saint Helens
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21. The Himalayan Mountains
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