Name:____________________________________ Date:_____________ Period:__________
NOAA LESSON 4 SUBDUCTION ZONES
Use this link: http://www.montereyinstitute.org/noaa/lesson04.html
Part 1: Watch the video clip and answer these questions. Pause and replay using the slider as needed.
1. Name 3 geologic events that can happen where two tectonic plates are colliding.
a. _____________________________________________________
b. _____________________________________________________
c. _____________________________________________________
2. What is Subduction? Where does it occur?
3. Only oceanic plates (not continental) can be subducted. Why?
4. In your own words, describe what happens during oceanic-continental plate convergence.
5. When two oceanic plates collide, which plate gets subducted? ________________________
6. In your own words, describe what happens during oceanic-oceanic plate convergence.
7. List two reasons why marine life flourishes near marine volcanoes.
a. _____________________________________________________
b. _____________________________________________________
Part 2: Click on the right side of screen on “Mariana Arc Exploration” and read the Introduction.
Click on each of the green circles and explore each of there volcanoes in quick time (wait for it to load).
Examine each profile and use the color scale to estimate the height of each volcano. If the volcano rises
above the water level, it creates an island.
Name
Nikko Volcano
Ahyi Volcano
Maug Volcano
Anatahan Volcano
East Diamante Volcano
Esmeralda Volcano
NW Rota Volcano
Approximate Depth Below Water Level (m)
Name:____________________________________ Date:_____________ Period:__________
NOAA LESSON 4 SUBDUCTION ZONES
Part 3: Click on the right side of screen on “Bathymetric Maps”. Read the “Introduction”, then follow the
“Instructions” to make a side graph profile of the volcano. When you are done, click on “show answer” to
reveal how accurate your graph is when compared with NOAA scientists. Then, answer questions below.
8. What are the deepest and shallowest points shown on the image?
9. Briefly describe the structure shown on the image.
10. Based on its topography and location in the Mariana area, what do you think this structure is?
11. Which side of a subduction zone did this structure form upon?
Part 4: Click on the right side of screen on “Bathymetry of Subduction”. Read the “Introduction and
answer the questions below.
12. The topography of the seafloor indicates the presence of a convergent plate boundary. Where is the
boundary?
13. Which plate is being subducted? What kind of plate is it, and how can you tell?
14. What is the other, over-riding plate composed of, and how can you tell?
15. How did the island chain form?
16. What benefits do the inhabitants of the islands receive from living on a plate boundary? What
hazards do they face?
17. Because of their remoteness, trenches have repeatedly been proposed as ideal sites for disposing
unwanted material, such as obsolete ships, toxic wastes, and even spent nuclear fuel. Evaluate the
use of trenches as dump sites, based on your knowledge of the geology involved.