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Features of the Ocean Floor. Exploration Time Line 1915 Scientists aboard the German ship Meteor used sonar to map the ocean floor. They used the device.

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Presentation on theme: "Features of the Ocean Floor. Exploration Time Line 1915 Scientists aboard the German ship Meteor used sonar to map the ocean floor. They used the device."— Presentation transcript:

1 Features of the Ocean Floor

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

3 German Ship Meteor

4 Exploration time line 1943 S CUB A Jacques Cousteau and Emile Gagnan invented 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.

5 First SCUBA gear 1943

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

7 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 Exploration Time Line 1978 Satellites 1978 Satellites Seasat A 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.

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

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11 Features of the Ocean Floor Continental shelf: a gently sloping, shallow area of the ocean floor 1. 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

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13 Continental Slope 1. This marks the true edge of a continentment, where the rock that makes up the continent slops and the rock of the ocean floor begins. 2. The gradient of the slope is lowest off stable coasts without major rivers and highest off coasts with young mountain ranges and narrow continental shelves.rivers 3. Most Pacific slopes are steeper than Atlantic slopes. Gradients are flattest in the Indian Ocean.

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15 Seamounts 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.

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17 Abyssal Plain A broad area covered with thick layers of mud and silt. The plains are largest and most common in the Atlantic Ocean, less common in the Indian Ocean, and even rarer in the Pacific, where they occur mainly as the small, flat floors of marginal seas or as the narrow, elongate bottoms of trenches.Atlantic Ocean Indian Ocean

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19 Mid-Ocean Ridge 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.

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21 Sonar SNaR 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.


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