Name __________________________________ Period _____________ Date ____________
Earth Science: Bill Nye Seafloor Spreading Video Worksheet
Directions: Watch the Bill Nye Seafloor Spreading Video at http://www.youtube.com/watch?v=GyMLlLxbfa4.
Use the information provided in the video and your knowledge of Earth Science to answer the following
questions. Use complete sentences for any credit.
1. Until the end of the Second World War, most scientists imagined the ocean floor to look like what?
2. How many miles long is the mid Atlantic Ridge?
3. The average seafloor depth is about how deep?
4. The mountains of the mid-Atlantic Ridge sit on average about how much higher than the surrounding
seafloor?
5. True or false: Harry Hess discovered that the age of the seafloor becomes progressively younger as it
moves farther away from the mid-ocean ridge.
6. Hess discovered that molten lava erupted along the mid-ocean ridges, creating new seafloor. As the
new seafloor formed, it pushed old seafloor away from the ridge. What term did Hess give to this
process?
7. The process that recycles the crust of the spreading ocean floor back inside the Earth is called what?