1. Ocean Floor Features

3. Label the Ocean Floor K. J. G. E. C. B. D. H. I. F. A. L.

4. Passive Continental Margin No plate boundary, so no subduction No plate boundary, so no subduction Ex: East coast of United States Ex: East coast of United States

5. Active Continental Margin Trench is formed from subduction of plate Trench is formed from subduction of plate Ex: West coast of South America Ex: West coast of South America

6. Ocean Exploration How do we know what it is like?

7. HMS Challenger (1872-1876) First scientific attempt to measure depth of ocean around the world Old Method – rope & weight used to measure

8. SONAR (Echo-Ranging) SOund Navigation And Ranging SOund Navigation And Ranging Uses echolocation like bats Uses echolocation like bats Sound Wave travel through water and bounce back when it hits object Sound Wave travel through water and bounce back when it hits object Uses speed of sound waves and time traveled to calculate the distance (depth) to the ocean floor Uses speed of sound waves and time traveled to calculate the distance (depth) to the ocean floor Began use in 1925 Began use in 1925 Helped submarines in WWII Helped submarines in WWII

9. Satellites In the 1970s, orbiting satellites began to collect ocean data In the 1970s, orbiting satellites began to collect ocean data This method proved to be much faster This method proved to be much faster

10. Satellite Coverage in 10 Days

11. Seasat launched in 1978 launched in 1978 measures direction & speed of ocean currents measures direction & speed of ocean currents

12. Geosat (used to map sea floor) measures changes in water heights to make maps of the ocean floor since ocean features affect the height of the water above them

13. New Satellites being used to map ocean floor

14. Underwater Submersibles Ex. of piloted vessels: The Alvin and Deep Flight Ex. of piloted vessels: The Alvin and Deep Flight Ex. of robotic vessels: JASON II and Medea (both are tethered together) Ex. of robotic vessels: JASON II and Medea (both are tethered together)

15. Jason II Jason II (ocean floor) Medea (ocean surface)

16. The Alvin

17. Deep Flight Submersible **Actually classified as an underwater airplane.