Features of the Ocean Floor

1. Features of the Ocean Floor

2. 1915 Scientists aboard the German ship named Meteor used sonar to map the ocean floor. They used a device called the echo sounder to produce pulses of sound. The crew then timed the return of the echoes. Exploration Time Line

3. German Ship Meteor

4. 1943 • Jacques Cousteau and Emile Gagnaninvented SCUBA, which stands for “Self Contained Underwater Breathing Apparatus”. A tank containing compressed air is strapped to the diver’s back and connected by a tube to a mouthpiece. SCUBA enables divers to explore to a depth of 40 meters. Exploration time line

5. First SCUBA gear 1943

6. 1960 submersibles Vehicles with very thick metal hulls protect explorers from extreme pressure and temperature, while enabling them to directly observe the ocean depths. Exploration time line

7. 1964 Alvin was the first deep-sea submersible capable of carrying passengers, usually a pilot and two observers. Its first untethered dive measured 35 ft. Now, after numerous upgrades and reconstructions, Alvin can plunge to a maximum depth of 14,764 ft.

8. 1978 Satellites SeasatA was the first satellite in Earth’s orbit to study the oceans. Since satellites make millions of observations a day, they provide data on rapidly changing and widespread ocean conditions. Such data include temperatures, algae growth patterns, and even the movement of large schools of fish. Exploration Time Line

9. Specific objectives were to collect data on sea-surface winds, sea-surface temperatures, wave heights, internal waves, atmospheric water, sea ice features and ocean topography

11. Continental shelf: a gently sloping, shallow area of the ocean floor • The actual boundary of a continent is not its coastline, but the edge of the continental shelf. 2. Most continental shelves are broad, gently sloping plains covered by relatively shallow water. 3. Water depth over the continental shelves averages about 60 meters (200 feet). 4. Sunlight penetrates the shallow waters, and many kinds of organisms flourish—from microscopic shrimp to giant seaweed called kelp. 5. Ocean currents and runoff from rivers bring nutrients to organisms that live on continental shelves Features of the Ocean Floor

14. Mountains that are completely underwater. • Seamounts - undersea mountains formed by volcanic activity - were once thought to be little more than hazards to submarine navigation. • Today, scientists recognize these structures as biological hotspots that support a dazzling array of marine life. • The biological richness of seamount habitats results from the shape of these undersea mountains. • Thanks to the steep slopes of seamounts, nutrients are carried upwards from the depths of the oceans toward the sunlit surface, providing food for creatures ranging from corals to fish to crustaceans. Seamounts

16. A broad area covered with thick layers of mud and silt. • The plains are largest and most common in the Atlantic Ocean. They are less common in the Indian Ocean, and even more rare in the Pacific. Abyssal Plain

17. A continuous range of mountains that winds around Earth, much as the line of stitches winds around a baseball. • At the top of the mid-ocean ridge, about 2 kilometers above the abyssal plain, but still 1 kilometer below the surface. • It consists of two parallel chains of mountains separated by a central valley. Mid-Ocean Ridge

19. Sound Navigation and Ranging, is a system that uses sound waves to calculate the distance to an object. The sonar equipment on a ship sends out pulses of sound that bounce off the ocean floor. The equipment then measures how quickly the sound waves return to the ship. Sound waves take longer to return if the ocean floor is farther away. Sonar