1. Chapter 14
The Ocean Floor

2. Section 14.1
The Vast World Ocean

3. The Vast World Ocean The “Blue Planet” or “Water Planet”
Nearly 71% of Earth’s surface is covered by the global ocean.
Oceanography – is a science that draws on the methods and knowledge of geology, chemistry, physics and biology to study all aspects of the world ocean.

4. The Vast World Ocean

5. The Vast World Ocean Geography of the Oceans
Of the 510 million square km of Earth’s surface 360 million square km is covered in water
The world ocean can be divided into four main ocean basins:
Pacific Ocean – largest and has the greatest depth
Atlantic Ocean – half the size of the Pacific and not quite as deep
Indian Ocean – slightly smaller than the Atlantic and is mainly in the southern hemisphere
Artic Ocean – 7% of the size of the Pacific

6. What percentage of Earth’s surface is covered by water?

7. Oceanography is the
science that draws on the methods and knowledge of geology, chemistry, physics and biology to study all aspects of the world ocean.
study of all the living organisms in the oceans.
study of ocean water chemistry.
study of the ocean floor and its topography.

8. Which of the world’s oceans is the largest and deepest?
Arctic Ocean
Atlantic Ocean
Indian Ocean
Pacific Ocean

9. The Vast World Ocean Mapping the Ocean Floor
The topography of the ocean floor is as diverse as that of the continents.
Bathymetry – is the measurement of ocean depths and the charting of the shape or topography of the ocean floor. (bathos = depth, metry = measurement)
Challenger expedition – Dec May 1876
First understanding of the ocean floors topography
127,500 km trip (every ocean except Artic)

10. The Vast World Ocean
Today’s technology – particularly sonar, satellites, and submersibles – allows scientists to study the ocean floor in a more efficient and precise manner than ever before.

11. The Vast World Ocean

12. The Vast World Ocean
Sonar – an acronym for sound navigation and ranging. It is also referred to as echo sounding.
Developed in the 1920’s.
Sonar works by transmitting sound waves toward the ocean bottom and timing how long it takes for the echo to come back.
Used to map the ocean floor
“Mowing the lawn” – method of sonar where a multibeam sonar is used in a back and forth motion to map the ocean floor

13. The Vast World Ocean

14. The Vast World Ocean Satellites
Satellites are able to measure small differences by bouncing microwaves off the ocean surface.
Using this new technology, scientists have discovered that the ocean surface is not perfectly flat.
Differences in the height of the ocean surface are caused by ocean-floor features.

15. The Vast World Ocean

16. Bathymetry is the measurement of ocean currents, tides and waves.
the measurement of ocean depths and the charting of the shape or topography of the ocean floor.
the study of the various sediments on the ocean floor.
the study of seismic activity on the ocean floor.

17. What does sonar equipment measure?
The density of the ocean’s water
The depth of the ocean floor
The sound produced by bottom-dwelling ocean creatures
The shape of the ocean surface

18. Scientists use satellites to measure the
Ocean floor depth.
Size of underwater features.
Sea-surface height.
Ocean’s salinity.

19. The Vast World Ocean
Submersibles – small underwater crafts used for deep-sea research.
First submersible used in 1934 by William Beebe
Dove 923 meters deep off of Bermuda
Steel sphere that was tethered to the ship
1960 – Jacques Piccard descended 10,912 meters into the Mariana Trench
Untethered submersible named Trieste
Manned submersibles
Alvin – can reach 4000 meters
Sea Cliff II – can reach 6000 meters
Today, many submersibles are unmanned and operated remotely by computers. These remotely operated vehicles (ROVs) can remain underwater for long periods.

20. Submersibles

21. Which of the following is NOT an example of a submersible?
Alvin
Trieste
Sea Cliff II
Red October