Sea Floor Spreading Lab

Name ______Class______Date ______

The places on Earth where plates pull apart have many names: divergent boundaries, mid-ocean ridges, and spreading centers. The term spreading center refers to the fact that sea floor spreading happens at these locations. In this lab, you will model the formation of new sea floor at a divergent boundary.

1. Cut 2 strips of paper that are 30 cm long and 7 cm wide. 2. Hold the 2 strips vertically and staple the bottom of the strips together. 3. Place the strips in between 2 tables, with the open end facing up-stapled end towards floor. 4. Separate and pull the strips so that they are flat on the table and extend about 2 cm on each side. 5. Use a marker to mark across the paper strips where they exit the tables. This will mark both strips at the same time. Use 2 different colors of marker and alternate the stripes. 6. Pull the strips evenly so that about 2 more cm of the strips exit the space in between the tables and mark the strip. 7. Repeat step 6, varying the amount of strips pulled out each time until you pulled out the whole strip. (you need at least 5 marker stripes

Sea Floor Spreading Lab Wrap Up Questions:

1. Why was Wegener’s theory of continental drift not accepted by other scientists?

2. What discovery confirmed Wegener’s theory?

3. What do the paper strips represent in your model?

4. What do the marker stripes represent in your model? (see TB pg. 265) 5. What represents the mid ocean ridge in your model?

6. Which part of the strip represent the oldest sea floor? The youngest?

7. If each 2 cm on the paper is equal to 3 million years, how could you use your model to determine the age of certain points on the sea floor?

8. Compare the ages of rock found on land to rock found on the sea floor. (see TB pg. 262). How are they similar and different?

9. What type of plate boundary are you modeling? (see TB pgs. 269-271) 10. Explain why the earth doesn’t keep growing in size? (see TB pg. 270)

11. The ______is a place where new sea floor forms through a process called ______. This occurs at a ______boundary (type).