1. EXPLORING THE OCEAN FLOOR http://www.youtube.com/watch?v=3GRA7ilM708

2. Difficulty in exploring the ocean
Sunlight does not penetrate far below the surface.
Water is very cold.
Tremendous pressure.

3. Technology Used To Study Ocean Bathymetry http://www. youtube
Bathymetry: measurement of ocean depths and the charting of the shape or topography of the ocean floor.
Echo Soundings (sonar): measuring the time it takes for the echoes to return to determine depth and shape of the ocean floor.
Multibeam and side-scan sonar give a more detailed image of the ocean floor.
Satellites: measures the variations of ocean surface elevation which is caused by gravitational attraction and mimics the shape of the ocean floor.

4. Features of the Ocean Floor

5. Ocean Floor Can Be Divided Into 3 Major Provinces
Continental Margins: shallow water areas close to the continents
Deep Ocean Basins: deep water areas farther from land.
Mid-Ocean Ridge: shallower areas near the middle of an ocean.

6. Continental Margin

7. Continental Shelf Gently sloping, shallow area of the ocean floor.
Extends from the shore beneath the ocean surface to a point where there is an increase in the slop (shelf break).
Flat and Featureless
Made of Granitic continental crust

8. Continental Slope Lies beyond the shelf break.
Where the deep ocean basin begins.
Contains submarine canyons. The Atlantic Ocean has many submarine canyons along its coast.

9. Continental Rise
Transition zone between the continental margin and the deep ocean floor.
Comprised of a huge pile of debris.

10. Deep Ocean Basin

11. Abyssal Plains
Flat or gently sloping areas of the deep ocean basin floor.
Extends from the base of the continental rise into deep ocean basins.
Among Earth’s flattest and smoothest regions an the least explored.
Formed by particles of sediment slowly drifting onto the deep ocean floor.
Most abyssal plains occur in the Atlantic and Indian oceans.
Cover about 40% of the ocean floor
Depths from 2,200 to 5,500 meters.

12. Seamount Mountain that does not reach the water’s surface.
Formed from extinct volcanoes.
If they have flattened tops they are called guyots.

13. Ocean Trenches Occurs at convergent boundaries.
May produce volcanic island arcs or volcanic mountain ranges.
Contains the deepest part of the world’s oceans (Mariana Trench).
Most are formed in the Pacific Ocean.

14. Mid Ocean Ridge

15. Mid-Ocean Ridge Mountain range that extends through all ocean basins.
Earth’s largest mountain chain.
Covers 23% of Earth’s surface.
Entirely volcanic and composed of basaltic oceanic crust.
Rift Valley: created by sea floor spreading
Hydrothermal Vents: Hot springs
Warm water vents
White Smokers
Black Smokers