1. Mapping The Ocean Floor SONAR – system that uses sound waves to calculate the distance to an object. Echosounding – Indirect method used for mapping the ocean floor using sound waves Energy waves such as sound waves are sent to the ocean floor from the surface Sound waves are reflected back to the ocean surface from the ocean floor and the time is recorded by the oceanographer Knowing the speed of sound in water and the time that it takes the sound wave to travel from the surface to the floor, back to the surface; allows the oceanographers to determine the depth of the ocean floor at a certain point

2. Ocean Depth = (# of seconds / 2) X 1500 m/s How deep is the ocean floor if it takes the sound wave 15 seconds to return to the boat? Step 1 – Write the equation Ocean Depth = (# of seconds / 2) X 1500 m/s Step 2 – Substitution OD = (15 seconds / 2) X 1500 m/s Step 3 – Answer with units 11,250 meters (m)

3. Ocean Floor There are many ocean floor features: Continental Shelves Continental Slopes Continental Rises Abyssal Plains and Hills Seamounts Guyots Mid-Ocean Ridges Trenches and Submarine Canyons Rift Valleys

4. Can you label the ocean floor parts?