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Geology
Plate Tectonics Computer Lab
Name_____________
Standards
 Explain plate tectonic theory and understand the evidence that supports it
 Describe convection as the mechanism for moving heat energy from deep within Earth to the surface
and discuss how this process results in plate tectonics, including:
• Geological manifestations (e.g., earthquakes, volcanoes, mountain building) that occur at
plate boundaries
Directions: Follow all the directions and go to the links provided for each section. Read the information, look
at the illustrations and watch the animations. Answer the questions as you progress through the lab.
Go to http://pubs.usgs.gov/gip/dynamic/dynamic.html
Click on Historical perspective
1. The word “tectonics” comes from a Greek root word. What does it mean?
2. What does the word “Pangaea” mean in Greek?
3. What was the forerunner to the theory of plate tectonics?
4. Who proposed the Principle of Uniformitarianism, and what does the principle tell us about geologic
forces?
5. Who first suggested, in 1596, that the continents have not always been in there present position?
6. What was the most compelling evidence that Wegener found to support the theory of Continental Drift?
7. What was the fatal weakness in Wegener’s Theory?
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Click on Developing the theory at the bottom of the page.
8. What were the four scientific developments that spurred the formulation of the plate tectonics theory?
i.
ii.
iii.
iv.
9. What did the U.S. research ship Atlantis discover about the sediment layer on the floor of the Atlantic?
10. What is the most prominent topographic feature on the surface of our planet?
11. What are the two groups of magnetic properties found in rocks?
12. What do the grains of magnetite in volcanic rocks record at the time of the rock’s cooling?
13. What is the name of the pattern that shows alternating bands of normally and reversely polarized rock?
14. What are the three pieces of evidence that support seafloor spreading?
i.
ii.
iii.
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15. What was the final piece of evidence that proved the seafloor spreading hypothesis?
16. As the Atlantic Ocean is expanding, what’s happening to the Pacific Ocean?
17. What happens to the old oceanic crust?
Go to http://www.nature.nps.gov/geology/usgsnps/pltec/pltec1.html
18. Beneath what structures is continental crust the thickest?
19. Why is the mantle denser than the crust?
20. What planet is Earth’s core larger than?
Click on Now climb back up to the lithosphere to take a closer look at tectonic plates
21. Approximately how many major plates are there on Earth?
22. How far do the fastest and slowest plates move per year?
Click on On to: The action is at the edges
23. What are the three types of plate boundaries?
24. Draw and label a cross-sectional view of a divergent boundary.
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25. Draw and label a cross-sectional view of a convergent boundary.
26. Draw and label a map view of transform boundary.
27. Where does most of the new crust on Earth form?
Click on Click here to learn more about divergent plate boundaries.
28. What ocean is being formed as the African and Arabian plates pull apart?
Click on animation and watch what happens at divergent boundaries. When finished, close the animation.
29. What are the two names for the chain of volcanoes and rift valleys that are formed at divergent
boundaries on the ocean floor?
Click the back button on your browser.
30. What does the fate of colliding plates depend on?
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Click on Click here to learn more about convergent plate boundaries.
31. What forms where two plates intersect in a subduction zone?
32. The subducting plate remains solid to at least what depth below Earth’s surface?
33. What do the released water and gases from the subducting plate do to the mantle above the plate?
34. What plate is subducting beneath the North American plate to produce the volcanoes of the NW coast?
35. When two oceanic plates collide, which one will sink?
36. Why is there no subduction when two continental plates collide?
37. What happens to solid rock at continental-continental boundaries?
Click the back button on your browser.
38. What is the name of the fault at the transform boundary between the North American and Pacific plates?
Click on Earth through time at the bottom of the page
Click on See continents move through time and scroll down through the reconstructions
39. What are the 5 pieces of evidence that geologists use to make these paleogeographic reconstructions?
i.
ii.
iii.
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iv.
v.
Click the back button on your browser.
40. What supercontinent existed during the late Proterozoic eon (1.1 billion years ago)?
41. During this time, what was the east coast of North America next to?
42. What does the world enter into when there are supercontinents?
Go to http://pubs.usgs.gov/gip/dynamic/hotspots.html#anchor19316266
43. Where do the vast majority of earthquakes and volcanoes occur?
44. Where have the Hawaiian Islands formed?
45. What theory did J. Tuzo Wilson propose?
46. What is moving over a hotspot to form the Hawaiian Island-Emperor Seamounts chain?
47. On what island are the oldest Hawaiian rocks found and how old are they?
48. On what island are the youngest Hawaiian rocks found?
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Click on Prominent world hotspots
49. Name 2 hotspots other than the Hawaiian Islands.
Click the back button on your browser.
Click on Some unanswered questions
50. The rock in the mantle is moving in a circular motion comparable to what substance when heated to
boiling?
51. What are the two main sources of heat within the Earth?
52. What is residual heat?
53. What is the name of the force that magma intruding into a spreading center provides to plate motions?
54. What is now thought to play a more substantial role in plate tectonics than seafloor spreading?
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