Plate Tectonic Test Study Guide
KEY
REVIEW QUESTIONS
1. Who was Alfred Wegener? 1800’s German scientist that created the theory of plate tectonics
2. The theory that Earth’s continents slowly move is called Continental Drift.
3. Tectonic plates move about 2 to 4 inches / 5 to 10 centimeters per year.
4. List how the theory of continental drift is supported?
Fossils
continent fit together like a puzzle
same type of rock found in South America and in Africa
climate
5. What is Panthlassa? 200 million years ago where all the oceans were once connected.
6. What is Pangaea? Ancient 200 million year old supercontinent where all the continents were
connected
7. What do scientists think moves plate tectonics? convection
8. Where do convection currents take place? In the asthenosphere
9. T F Oceanic crust is younger at a ridge and older near a trench and this supports the
theory of seafloor spreading.
10. How long ago do scientists believe Pangaea begin breaking apart? 200 million years
11. Magma rising to the surface of the Earth is less dense than the surrounding rock.
12. When it reaches the surface, magma is called lava.
13. List the 4 types of volcanoes. Stratovolcano, Cinder Cone , Caldera, & Shield.
14. Describe Stratovolcano composed of many layers of hardened lava, and volcanic ash
15. Describe Cinder Cone Volcanos Straight sides with steep slopes; large summit crater
16. Describe Sheild Volcanos Very gentle slopes,
17. Describe Caldera Volcanos cauldron-like volcano form by a hot spot
18. What is a hot spot? Heated areas coming from the Earth’s mantle inside a plate
19. What state was formed from a hot spot? Hawaii
20. How does volcanic ash effect the environment? Ash can cause the average global surface
temperature to drop, smother crops, causing food shortages and loss of livestock, and ash can
mix with rainwater and melt-water, flow downhill, and destroy or move objects in its path.
21. Draw pictures of the three types of boundaries:
Divergent
Convergent
Picture showing plates
moving apart.
Transform/Strike-slip
Picture showing plates
Picture showing plates
moving toward each other.
sliding past each other.
22. How does a mid-ocean ridge form? From a divergent boundary pushing up seafloor.
23. What do tectonic plates do at a divergent boundary? Move apart
24. How are mid ocean ridges formed? By divergent plate boundaries
25. What occurs at divergent boundaries? Rift Valleys, Mid-Ocean Ridges
26. Name the most famous transform fault in the United States. San Andreas, California.
27. Which of the 3 types of boundaries occur at an ocean trench? convergent
28. T F Tectonic plates match ocean and continental boundaries.
29. T
F Transform plates scrape past one another.
30. List the three types of convergent boundaries. Continental-Continental, Oceanic-Oceanic,
& Oceanic-Continental.
31. What two types of plate collisions form mountain ranges continental-continental, oceaniccontinental (ocean mountains)
32. What plates collide to form an ocean trench? Oceanic and continental subduction
33. What type of boundary occurs at a continental-continental collision? convergent
34. What geologic feature forms at a continental-continental collision? Mountains
35. What process causes a plate to sink below another plate? subduction
36. Going from the surface to the center of the earth, list the layers in order. Lithosphere,
asthenosphere, mantle, outer core, inner core
37. Explain how convection currents work. Heated rocks in the asthenosphere become less
dense and rise while other rocks cool and become more dense and sink.
38. List the three types of mountains. Folded Mountains, Fault-Block Mountains, &
Volcanoes.
39. Draw and describe Folded Mountains.
Rock under extreme pressure for long periods of time will fold like clay. Folding bends many
layers of rocks without breaking them.
40. Draw and describe Fault Block Mountains.
Mountains with sharp, jagged peaks are produced when rock layers break apart at convergent
boundaries and are tilted upward.
41. Draw and describe Volcanoes Mountains.
Magma forced out of the Earth.
42. Why do you scientists think ocean fossils are sometimes found on the tops of mountains?
Seafloor has been raised by tectonic plate movement
43. If a fossil is found multiple places in the world, what have scientists hypothesize might
have happened a long time ago? They were once on a single continent that has separated
44. North American plate consists of both continental and oceanic crust.
45. Tectonic plates are large pieces of the lithosphere that float on top of the asthenosphere.
Vocabulary
Mid-Ocean Ridge
Ocean Trench
Asthenosphere
Lithosphere
Mantle
Inner Core
Outer Core
Fossil
Volcano
Strato/Composite volcanoes
Cinder Cone volcanoes
Caldera volcanoes
Folded mountains
Fault Block mountains
Panthalassa
Subduction - The process by which an oceanic tectonic plate sinks under another plate into
Earth’s mantle.
Rift valley - A deep valley formed as tectonic plates move apart, such as along a mid-ocean
ridge.
Folded mountain - A mountain that forms as continental crust is compressed and rocks bend
into large folds.
Fault - A fracture in the Earth’s lithosphere along which blocks of rock move past each other.
Alfred Wegener - A German scientist from the 1800s who came up with the idea of continental
drift.
Hot spot - An area where a column of hot material rises from deep within a planet’s mantle and
heats the lithosphere above it, often causing volcanic activity at the surface.
Sea-floor spreading - Scientists learned that the ridges form along cracks in the crust. Molten
rock rises through these cracks, cools, and forms new oceanic crust. The old crust is pulled
away to make new room for new material.
Tectonic plates - One of the large, moving pieces into which Earth’s lithosphere is broken and
which commonly carries both oceanic and continental crust.
Continental drift - They hypothesis that Earth’s continents move on Earth’s surface.
Divergent boundary - A boundary where tectonic plates move apart, characterized by a midocean ridge or a continental rift valley.
Convergent boundary - Where tectonic plates push together, characterized either by subduction
or a continental collision.
Transform boundary - A boundary along which two tectonic plates scrape past each other, and
crust is neither formed nor destroyed.
Pangaea - A hypothetical supercontinent that included all of the landmasses on Earth. It
began breaking apart about 200 million years ago.
Convection current - A circulation patter in which material is heated and rises in one area, then
cools and sinks in another area, flowing in a continuous loop.