Find a Plume, Find a Vent
How do researchers find deep--sea hydrothermal vents that are over 2000 meters (more than a mile and a half) below the ocean surface and are very tiny when compared with the vast ocean?
In this activity you will use a web--based interactive to mimic the process that scientists use to search mid--ocean ridges for hydrothermal vent sites. Your assignment is to keep a "journal" as you work through the interactive. Answer the questions as you work through these instructions and submit them to the Find a Vent Assignment area when you finished.
Before you begin the activity think about how scientists might locate deep--sea hydrothermal vents and make a journal entry that captures your thinking about the following questions. Keep in mind that we're just looking for your initial thoughts. At this point you don't have to have the correct method. A vent site would be about 100 meters wide and 10 meters high, and the area known to contain vents might be about 160 square kilometers.
- How far below the surface are mid--ocean ridges?
- What are deep--sea vents? Why are deep--sea vents found along mid--ocean ridges?
- How do you think researchers study the bottom of the ocean from on board a ship? How else can they study the bottom of the ocean? How expensive might it be to conduct such a study?
- How would marine researchers know where to look for hydrothermal vent sites? How could they be certain they've found a vent?
After you've entered your thoughts about the above questions go to "The Library" section of the interactive and work through the slideshow and animations that describes the way possible vent locations are identified.
- In your journal describe the images you see of the tow--yo and the research vessel. How do these images compare with your original ideas for finding deepsea vents?
- How do the physical characteristics of the vents make it possible for scientists to find them using the tow--yo?
Once you've familiarized yourself with the basics you're ready to try finding one yourself. Click on "The Expedition" button and follow the instructions on the interactive to see if you can figure out the location of a vent. Record your process in your journal, describing what happened each time you tried to find a vent. If you find a vent on the first or second try, take another turn; that way, you can see if you really understand how to find it, or if it was just luck!
Use the following questions to guide your journal entries:
- What happened on your first try? What helped you find the vent? What further information do you need?
- What happened on your subsequent tries? What helped you find the vent?
- Draw some conclusions from your virtual field research. How hard was it to find the vent? Compare your virtual experience with the experiences of researchers on board ships at sea. What challenges would those researchers face that you did not?
- What did you learn from this investigation of hydrothermal vents?
- What further questions do you have?
When you finish, submit your journal document to the Find a Vent Assignment area.