geological oceanography ocean topography the scientific study of the origin, history, and structure...
TRANSCRIPT
![Page 1: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/1.jpg)
Geological OceanographyOcean TopographyThe scientific
study of the origin, history, and structure of the earth
![Page 2: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/2.jpg)
Topography is a graphic representation of the surface features
of a place or region …in this case, the ocean basins.
What do ocean basins look like?
![Page 3: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/3.jpg)
![Page 4: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/4.jpg)
How do we know what it looks like?
Soundings are made by sending a sound pulse into the water.
![Page 5: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/5.jpg)
• Echosounders are attached to the hull of a ship or a towed vehicle.
• An echosounder sends a sound pulse into the water. The sound energy travels through the water to the ocean bottom where it is reflected back towards the source, received, and accurately measured.
![Page 6: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/6.jpg)
Undersea structures shown by Sonar
• This surprised oceanographers who expected the ocean bottoms to be smoother, more like a bowl (deepest in the middle and getting shallower towards continents).
![Page 7: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/7.jpg)
Features found on the seafloor
Continent Mid-ocean ridge Sea mount
Oceanic trench
Abyssal plain
Continental shelf
Central rift zoneDepth (m)
![Page 8: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/8.jpg)
Geological Oceanography Journal Question
• http://videos.howstuffworks.com/science/sonar-videos-playlist.htm#video-30297
1. Describe how scientists find out what the ocean floor looks like?
![Page 9: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/9.jpg)
The ocean basin: Structures1. Continental Margin: Continental Shelf
Continental SlopeContinental RiseSubmarine Canyons
2. Deep Ocean Basin: Abyssal PlainsOceanic ridges
3. Trenches4. Seamounts and Guyots5. Atolls
![Page 10: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/10.jpg)
Submerged, outer edge of the continents.
Two types: 1. Active Margin (Pacific)
2. Passive Margin (Atlantic)
Found on the leading edge of the continent crashing into an oceanic plate.No collisions taking place, tectonic activity is minimal
![Page 11: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/11.jpg)
Continental Shelf:
Similar to the continent (compared to the deep ocean).
They have hills, depressions, mineral and oil deposits.
In Atlantic Canada, the continental shelf holds the best fishing areas.
![Page 12: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/12.jpg)
Submarine Canyon: on the edge of the
continental shelf• V-shaped indentations into the
continental shelf, usually ending in a fan shaped wedge of sediments.
![Page 13: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/13.jpg)
The Gully!• Submarine canyon off Nova Scotia• Marine protected area because of the rare corals found
there• The natural gas pipeline goes right by it though!
The Gully
![Page 14: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/14.jpg)
• This coral forms colonies up to two meters high and takes between 200 and 500 years to grow such a colony. They only grow 1.5 millimeters a year."
Bubble Gum coral
Largest reported from N.S. was 7m tall!
![Page 15: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/15.jpg)
Deep Ocean Basin• Abyssal plains: From the
Greek meaning “without bottom”. They are flat, cold, dark, featureless expanses of sediment-covered ocean floor. They are most common in the Atlantic.
• Ocean Ridges: Mountainous chains of actively spreading ocean floor. They can rise 2km from the ocean floor and sometimes form islands such as Iceland, the Azores and Easter island.
![Page 16: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/16.jpg)
![Page 17: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/17.jpg)
Mid-Atlantic Ridge
![Page 18: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/18.jpg)
Trenches• Deep gap in ocean floor,
formed by movement of plates.
• Example: Mariana Trench is 10,668 meters deep
• They are among the most active areas on Earth.
• They are the deepest areas of the Earth’s crust.
• 90% of trenches are found around the Pacific rim.
![Page 19: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/19.jpg)
![Page 20: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/20.jpg)
Seamounts and GuyotsBoth are undersea volcanoes that originated at a
hotspot or along a ridge Guyots once reached the surface of the ocean
and have flat, eroded topsSeamounts never reached the surface, so they have pointy tops
![Page 21: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/21.jpg)
Atolls• A ring shaped island of coral reefs and coral
debris. These often form over sinking inactive volcanoes.
![Page 22: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/22.jpg)
Ocean floor features:
Trenches
Mountain chains
Sea mounts
Fracture zones
![Page 23: Geological Oceanography Ocean Topography The scientific study of the origin, history, and structure of the earth](https://reader035.vdocuments.net/reader035/viewer/2022062519/5697c01c1a28abf838cd01e0/html5/thumbnails/23.jpg)
Copy and complete this Chart
Ocean Structure Two – Three Key Facts
Continental Margin
Deep Ocean Basin
Trenches
Seamounts and Guyots
Atolls